An interconnect for connecting a needle electrode to a neurological testing device, the interconnect comprising: a needle-side connector and a device-side connector, wherein the needle-side connector and the device-side connector have complementary aspects so as to ensure that the correct needle electrode is used with a given neurological testing device.

Surgical procedures often require the application of peripheral nerve blocks, which generally involve injecting a patient with a local anesthetic near a nerve in order to eliminate any pain or sensation during the surgical procedure.
In addition, patients with nerve damage due to maladies such as carpal tunnel syndrome often require the injection of a drug (such as a steroid or an anesthetic) near the nerve. In this respect it should be appreciated that an estimated 40 million Americans suffer from chronic pain symptoms, with more than half of them over the age of fifty-five. And nearly 60% of all of those who suffer from diabetes also have acute peripheral neuropathy. Local anesthesia can be applied to relieve chronic or acute pain situations, with two basic techniques being used: peripheral nerve block and plexus anesthesia. As noted above, peripheral nerve block is the injection of a local anesthetic in the vicinity of a peripheral nerve so as to anesthetize the region surrounding the nerve. Plexus anesthesia is the injection of a local anesthetic in the vicinity of a network of intersecting nerves (i.e., a nerve plexus) in order to anesthetize the entire area of several or all of the nerves stemming from the plexus. Thus, regional nerve blocks and plexus anesthesia can aid patients who suffer from chronic pain such as lower back pain, neck pain, sciatica (from a herniated disc), spinal stenosis and reflex sympathetic dystrophy (a complex regional pain syndrome). In addition, regional nerve blocks and plexus anesthesia can also help those suffering from shingles, cancer and painful peripheral vascular disease.
In order to provide effective peripheral nerve blocks and plexus anesthesia, it is important to first accurately locate the nerves which are to be anesthetized. Peripheral Electrical Nerve Stimulation (PENS) can be used to accurately locate the targeted nerve. In PENS, electrical pulses are sent, via a needle electrode, into the desired nerve(s) so as to trigger depolarization of the nerve and elicit a reaction in the muscle which is innervated by the nerve. A constant current source, delivered via the needle electrode, supplies the depolarizing current to the nerve. The amount of charge received by the nerve depends on the distance between the tip of the needle and the nerve: the closer the tip is to the nerve, the greater the reaction of the muscle. Thus, by monitoring muscle reaction, the peripheral nerve can be reliably located. Once the peripheral nerve has been located, one of several anesthetics, in combination with a steroid and/or opioid, can be administered by the physician.
Needle electrodes are also used in connection with botulinum injections. More particularly, nearly three million botulinum injections are administered annually in the United States for cosmetic purposes or for therapeutic purposes (e.g., for treatment of focal dystonia, or for treatment of painful muscle spasms, etc.). The injection of the botulinum toxin is a process that takes ten to thirty minutes. A topical anesthetic is applied to the area in question for numbing purposes, and then small amounts of the botulinum toxin is injected into predetermined areas with an extremely thin needle. Needle electrodes are used to help identify the appropriate areas for the botulinum injections.
Needle electrodes are also used for electromyography (EMG) studies. More particularly, electromyography is a technique for recording and evaluating the physiological properties of muscles, and is widely used to diagnose and determine the underlying causes of most peripheral neuropathies, including carpal tunnel syndrome and radiculopathy. In electromyography, an electromyograph is used to detect the electrical potential between muscle cells while they are active and at rest. To perform intramuscular EMG, a needle electrode is inserted through the skin and into the muscle tissue. A trained medical professional observes the electrical activity while inserting the needle electrode. In intramuscular EMG, three types of signals are generally studied: (i) the electrical activity of the muscle when the needle is inserted, (ii) the electrical activity of the muscle at rest, and (iii) the electrical activity of the muscle when it is consciously contracted by the patient. Abnormal spontaneous activity of the muscle at rest, and abnormal shape, size and/or frequency of the motor unit potential of the contracted muscle, may indicate nerve and/or muscle damage.
Needle electrodes are also used in many other diagnostic and/or treatment systems.
The needle electrodes currently used for near-nerve anesthesia injections, botulinum injections, EMG applications, etc. are so-called "off-the-shelf" products, in the sense that they have a distal end which is specifically configured according to the intended use and a proximal end which can be inserted into any common cable connector so that the needle can be electrically connected to a neurological testing device. These conventional needle electrodes (which are commonly referred to in the industry as simply "needles") currently have no means for ensuring that the correct type of needle (i.e., an anesthesia needle, a botulinum needle, an EMG needle, etc.) is connected to a neurological testing device, or for ensuring that a needle has not been previously used.
By way of example but not limitation, two needle electrodes ("needles") currently commercially available are the STIMUPLEX®—a needle manufactured by B. Braun for drug therapy, and the NEUROLINE® concentric needle manufactured by AMBU® for EMG. The Braun STIMUPLEX® needle is a standard, beveled, hypodermic needle electrode which fits into any Deutsches Institut für Normung (DIN) 42802 cable connector. The Braun STIMUPLEX® needle provides a pinpoint electrode and smooth insertion as well as atraumatic puncture of the skin. The AMBU® NEUROLINE® needle is a standard, beveled, concentric needle electrode, with TEFLON insulation for electrical protection, which also fits into any DIN 42802 cable connector. The AMBU® NEUROLINE® needle provides a sharp tip for easy insertion, and an extra-smooth coating for low insertional friction. Thus it will be seen that the Braun STIMUPLEX® needle used for drug therapy differs significantly in construction from the AMBU® NEUROLINE® needle used for EMG. However, both needles fit into any DIN 42802 connector—meaning that the Braun STIMUPLEX® needle might inadvertently be used in an EMG procedure (rather than in the drug therapy procedure for which it was designed), or the AMBU® NEUROLINE® needle might inadvertently be used in a drug therapy procedure (rather than in the EMG procedure for which it was designed), etc. Neither of the foregoing needles, nor any of the other electrophysiological needles currently on the market, provides an effective or practical means for successfully ensuring that the correct needle is used with a given neurological testing device, or for prevention of its re-use.
In addition to the fact that needle constructions differ according to their intended use, there is a further reason why it may be important to be able to properly identify the needle electrode being connected to a neurological testing device. More particularly, it is anticipated that future designs of needles may incorporate special features that may dictate certain operating parameters. By way of example but not limitation, a needle may have a dielectric on the outside of the needle that requires a minimum breakdown voltage. In this situation, as well as many others, it may be important to ensure that the proper needle is being used with a given neurological testing device.
The re-use of medical needles, while not necessarily a major issue in the United States, is a serious problem in lesser-developed countries where medical resources are frequently scarce. The World Health Organization has estimated that at least half of all medical injections in 17 developing countries were administered with re-used needles, significantly contributing to the skyrocketing rate of AIDS and HIV. An effective and fail-safe means of detecting the re-use of needles would be of substantial benefit to the medical community.
There is, therefore, a need in the industry for a simple, cost-effective approach for ensuring that the proper needle electrode is used with a neurological testing device, and for detecting when a needle has been previously used.
For electrophysiological needles, the interconnect used to couple the needle electrode with the neurological testing device is a key component which is present in all systems. This key component provides an opportunity to ensure that the proper needle electrode is being used with a given neurological testing device and that the needle has not been previously used.
It is, therefore, a principal object of the present invention to provide a simple, cost-effective interconnect which can be used to quickly determine the identity of an electrophysiological needle and, optionally, detect when a needle has been previously used.

Disposable needle electrode with identification, and alterable, connector interface


A semi-conductive tubular assembly (30) or molded rubber cap is used in a cable joint for medium voltage electric power cables (10, 20). The conductors (13, 23) of the cables are connected together by a connector (40) constituted by a bolted contact assembly having a tubular shape and wherein the conductor ends are maintained by bolts. Two rubber caps (30a, 30b) preferably overlap each other in the middle of the connector. Each cap has an internal shape adapted to compensate for the gap resulting from the difference in diameter between the conductor insulation and the connector, as well as for the eccentric position of the latter with respect to the conductors. By mating the change of shape (31a, 31b) between the underlying connector (40) and the conductor insulation (12, 22), the caps provide a relatively cheap and efficient solution for an electrically reliable product, e.g. by reducing local electric stresses. In addition covering the sharp edges, mainly of the underlying connector, the molded rubber cap has an outer surface that provides a conical transition with a relatively slow slope for smoothing the above diameter transition.

The present invention relates to a cable joint between two medium voltage electric power cables, each cable having a conductor surrounded by a conductor insulation and a semi-conductive layer, said cable joint comprising:
a connector constituted by a bolted contact assembly having a tubular shape and being adapted for connecting together bared ends of said conductors engaged in said contact assembly and maintained therein by means of bolts; and
an insulating sleeve adapted for covering at least said connector.
Such a cable joint is already known in the art, e.g. from the UK Patent Application GB-A-2 254 739 entitled xe2x80x9cCable Jointxe2x80x9d by J. W. Weatherley et al. (Raychem Limited), first filed on Mar. 25, 1991. The connector used in this known cable joint is covered by a heat shrinkable insulating sleeve, generally known as joint-body. The heat shrinkable joint-body is positioned over the connector and caused to shrink by heating and, once the heating is removed, the joint-body remains in place. The retracted joint-body tends to follow the shape of the underlying connector and conductor insulation of each cable. However, there are remaining gaps at the location where the diameters change, i.e. between the conductor insulation and the contact assembly, as well as other gaps due to the irregular shape of this bolted contact assembly.
The difference in diameter between the conductor insulation and the contact assembly is mainly due to the fact that the bolted contact assembly generally covers a wide range of cross-sections, e.g. from 50 to 300 mm2, and is thus larger than the conductor insulation. Such a bolted contact assembly is for instance known in the art from the UK Patent Application GB-A-2 262 396 entitled xe2x80x9cConnector for elongate objectsxe2x80x9d by D. J. Hollick (B and H), first filed on Dec. 14, 1991. Additionally to the fact that the diameter of the bolted contact assembly is bigger than the diameter of the conductor insulation, it is further positioned eccentrically with respect to the conductor. This is due to the presence of the bolts which still increase the dimensional difference between conductor insulation and the connector. As a result, the insulating sleeve is not able to closely follow the contours of the conductor insulation and of the bolted contact surfaces, leaving a large air gap in front of the contact, right at the electrically speaking most critical point of the joint. This is a problem, especially for applications above 10 or 15 kVolt.
In the known cable joint, these gaps are reduced by wrapping the connector with an amount of insulating mastic.
However, it is difficult to determine how much filling has to be put into the gaps under the insulating sleeve. Furthermore, the mastic used to compensate for the gaps may flow away, e.g. during temperature cycles. The insulating sleeve, being relatively rigid once retracted, might not compensate for this flow, resulting in the appearance of more gaps.
Another problem with the known cable joint is that high electrical fields exist at the edges of the connector. These local electrical stresses may result in partial discharges and in product failure.
An object of the present invention is to provide a cable joint of the above known type but which is better adapted to sustain local electric stresses, especially at the intersection between the connector and the conductor insulation, while being also better adapted to take into account the diameter differences of the items under the insulating sleeve.
According to the invention, this other object is achieved due to the fact that said cable joint is further provided with two molded caps of semi-conductive rubber covering part of the conductor insulation of the two cables and joining each other over said connector, each of said caps having an internal shape adapted for being engaged over the connector and over the conductor insulation and for mating the change of dimension between said connector and said conductor insulation.
In this way, a relatively cheap and efficient solution is provided to compensate for the gap resulting from the difference in diameter between the conductor insulation and the connector, as well as for the eccentric position of the latter. Furthermore, the semi-conductive material used for making the caps provides a better distribution of the electrical fields around the connector and thus an electrically more reliable product than that of the known prior art.
Another characterizing embodiment of the present invention is that each of said molded caps has an external shape adapted for smoothing the transition from the external diameter of said conductor insulation to the external diameter of said connector by providing an external conical transition with a relatively slow slope.
This characteristic of the caps having an outer surface smoothing the sharp edges of the contact, e.g. the shearing bolts, is also beneficial to reduce local electric stresses.
Also another characterizing embodiment of the present invention is that said two molded caps overlap each other in the middle of the connector.
In this way, the molded caps are usable for different lengths of bolted contacts. The overlapping further ensures that the underlying connector is not exposed.
Still another characterizing embodiment of the present invention is that said insulating sleeve is a cold shrinkable joint-body adapted, when retracted, to cover said connector covered by said molded caps, the conductor insulation and part of the semi-conductive layer of both said cables.
The heat shrinkable joint-body known from the above first mentioned UK Patent Application is caused to retract by heating. In this condition the material becomes elastic and is able to exert pressure on the underlying filling, but once cooled down, it becomes rigid again and will not compensate for flowing of the filling material. On the other hand, a cold shrinkable joint-body is positioned by removing the support tube that maintains it in an expanded status. When retracted over the connector, the cold shrinkable joint-body exerts a pressure on the underlying layers. This pressure is maintained for ever, without any heating, and all the underlying items, including any filling mastic, are so maintained in place.
Yet another characterizing embodiment of the present invention is that said cold shrinkable joint-body comprises an inner layer of insulating mastic, an intermediate layer of insulating material and an outer layer of semi-conductive material.
This mastic is conformed by the shrinking joint body and fills any possible remaining irregularities over the connector and conductor insulation area.
The present invention also relates to a method of forming a joint between two medium voltage electric power cables, each cable having a conductor surrounded by a conductor insulation itself surrounded by a semi-conductive layer, the end of the semi-conductive layer being cut-back to expose a bared end of said conductor insulation and the end of the conductor insulation being removed to expose a bared end of said conductor.
In this method:
a molded cap, having a first section with a first internal diameter adapted for being engaged over said conductor insulation and a second section with a second internal diameter adapted for being engaged over a connector, is engaged over each of said conductor insulations;
the bared conductor ends of the two cables are connected together by means of said connector constituted by a bolted contact assembly having a tubular shape, said conductor ends being maintained therein by means of bolts; and
the molded caps are slid over said connector until they joint each other with their second section covering said connector, said caps having, between their first and their second section, an internal shape adapted for mating the change in dimension between said first and said second internal diameter.
In this way, a cable joint is obtained whereof the internal shape of the caps closely follows the contours of the underlying conductor insulation and external surface of the bolted contact assembly, reducing and electrically neutralizing thereby any possible air gap between these items.
Another characterizing embodiment of the present method is that each of said molded caps has an external shape adapted for smoothing the transition from the external diameter of said conductor insulation to the external diameter of said connector by providing an external conical transition with a relatively slow slope.
A conductor connector area with a smoother outer surface is so obtained.
The present invention further also relates to a tubular assembly for a cable joint adapted for covering a connector constituted by a bolted contact assembly adapted for connecting together bared ends of conductors of two medium voltage electric power cables.
A further object of the present invention is to provide a tubular assembly able to improve the quality of the cable joint.
According to the invention, this object is achieved due to the fact that said tubular assembly is constituted by two molded caps made of semi-conductive rubber and joining each other over the connector, and that each of said molded caps has an internal shape adapted for being engaged over said connector and the insulation of said conductor and for mating the change of shape between said connector and said conductor insulation.
In this way, the internal shape of the caps closely follows the contours of the underlying conductor insulation and the external surface of the bolted contact assembly, reducing and electrically neutralizing thereby any possible air gap between these items.
Another characterizing embodiment of the present invention is that each of said molded caps has an external shape adapted for smoothing the transition from the external diameter of a conductor insulation of said cable to the external diameter of said connector by providing an external conical transition with a relatively slow slope.
In this way, the connector has a smoother outer surface with all the advantages thereof, e.g. reducing the electrical stresses and allowing the joint body to adapt better to the underlying surface.
Further characterizing embodiments of the present cable joint using a semi-conductive tubular assembly, method for obtaining such a cable joint and tubular assembly for this type of cable joint are mentioned in the appended claims.

Cable joint using a semi-conductive tubular assembly and method to obtain a smoothly shielded connector


[Problem] Provided are: a pattern forming method by which a pattern can be formed by development using a thermosetting resin composition and a cured layer having excellent curability can be obtained; a thermosetting resin composition used in the pattern forming method; and a printed circuit board.

Conventionally, as a material used for a solder resist of a printed circuit board, a photocurable resin composition which can be developed with an aqueous alkaline solution is employed. For example, in Patent Documents 1 and 2, a photocurable resin composition which contains an epoxy acrylate-modified resin induced by modification of an epoxy resin (hereinafter, may be simply referred to as "epoxy acrylate") is used.
One example of a method of forming a solder resist using such a photocurable resin composition is a method in which a photocurable resin composition is coated and dried onto a substrate to form a resin layer and the resulting resin layer is then irradiated with a light in a pattern form and developed with an alkali developer, thereby forming a solder resist.
Meanwhile, Patent Document 3 discloses a composition which has an improved desmear resistance by not containing a thermosetting resin having a secondary hydroxyl group. Using this composition, for example, a solder resist is formed by screen printing.
Further, Patent Document 4 discloses a method of forming a solder resist layer composed of a thermosetting resin composition on one side of a printed circuit board and a solder resist layer composed of a photocurable resin composition on the other side. Patent Document 4 also discloses a method of forming an opening having a relatively small diameter on the solder resist composed of a thermosetting resin composition by laser processing and an opening having a relatively large diameter on the solder resist layer composed of a photocurable resin composition by photolithography.

Pattern forming method, alkali-developable thermosetting resin composition, printed circuit board and manufacturing method thereof

Abstract: [Means for Solution] The pattern forming method according to the present invention is characterized by comprising the steps of: (A) forming a resin layer composed of an alkali-developable thermosetting resin composition comprising a photobase generator on a substrate; (B) activating the photobase generator contained in the alkali-developable thermosetting resin composition by irradiation with a light in a pattern form so as to cure an irradiated part; and (C) forming a negatively patterned layer by removing a non-irradiated part by alkali development.


An electrical connector including a housing; electrical contacts connected to the housing; and electrical shorting members connected to the housing. Each contact includes a male contact area to form a male electrical connector. Each shorting member is adapted to electrically connect at least two of the contacts to each other. Each one of the contacts is connected to at least one other contact of the contacts in the connector by the shorting member. The shorting members are each movable to a position spaced from the contacts. The contacts are aligned in an array of at least two rows with multiple ones of the contacts in each row.

1. Field of the Invention
The present invention relates to electrical connectors and, more particularly, to an electrical connector assembly having electrical shorting members.
2. Brief Description of Prior Developments
U.S. Pat. No. 6,186,805 discloses a short circuit electrical connector assembly. The assembly has a male electrical connector with shorting members that contact the male electrical contacts until the female electrical connector is mated with the male electrical connector. Electrical connector assemblies which use a short circuit on contacts when two mating electrical connectors are not mated with each other are used in automobile air bag safety systems. The short circuit helps prevent an air bag ignition system from inadvertently igniting when the mating electrical connectors are disconnected from each other.
There has been a significant increase in the use of air bags in automobiles in recent years. In addition, there has been an increase in the number of air bags used in individual vehicles, including side air bags and seatbelt air bags. There is a desire to reduce the number of electrical connectors used in automobile air bag safety systems and to centralize air bag electronics in order to reduce manufacturing costs.
In accordance with one aspect of the present invention, an electrical connector is provided including a housing; electrical contacts connected to the housing; and electrical shorting members connected to the housing. Each contact includes a male contact area to form a male electrical connector. Each shorting member is adapted to electrically connect at least two of the contacts to each other. Each one of the contacts is connected to at least one other contact of the contacts in the connector by the shorting member. The shorting members are each movable to a position spaced from the contacts. The contacts are aligned in an array of at least two rows with multiple ones of the contacts in each row.
In accordance with another aspect of the present invention, an electrical connector is provided comprising a housing; and electrical contacts connected to the housing. The contacts are aligned in an array comprising two rows of the contacts. The housing comprises at least two rows of spaced electrical shorting member mover projections extending forward at a forward mating side of the housing for insertion into a mating electrical connector. The at least two rows of projections are located in separate planes generally between the two rows of contacts.
In accordance with one method of the present invention, a method for assembling an electrical connector assembly is provided comprising steps of providing a female electrical connector with two rows of female electrical contacts and a housing with two rows of shorting member mover projections at a front end of the housing; providing a male electrical connector with two rows of male electrical contacts and two rows of movable electrical shorting members connecting pairs of the male electrical contacts in each row to each other; and connecting the male and female electrical connectors to each other, wherein the two rows of shorting member mover projections extend into the male electrical connector to move the two rows of shorting members off of electrical contact with their respective rows of the male contacts, and wherein the shorting members in a first one of the rows of shorting members are moved in an opposite direction from the shorting members in a second one of the rows of shorting members.

Electrical connector assembly with shorting members


A method of forming a silicone resin film for protecting a semiconductor substrate on the substrate for a certain period of time and then removing the film from the substrate including the steps of: (a) forming the silicone resin film, on at least one portion of the substrate; (b) treating the film with an organic solvent, so that a majority of the film is dissolved in the organic solvent and thereby removed from the substrate and that a residue remains on the substrate; (c) oxidizing the residue to silicon oxide; and (d) treating the silicon oxide with an aqueous solution containing at least one of hydrogen fluoride and ammonium fluoride, so as to dissolve the silicon oxide in the solution and to thereby remove the silicon oxide from the substrate is described. The silicone resin film formed on the substrate can be easily completely removed, without damaging the electrical characteristics of the semiconductor.

1. Field of the Invention
The present invention relates in general to a method of producing a semiconductor device and more particularly to a method of forming a silicone resin film for protecting a semiconductor substrate on the substrate and then removing the film from the substrate.
2. Description of the Prior Art
Silicone resin, which contains organopolysiloxane, is superior in heat resistance and cold resistance. It is also superior in chemical resistance and thus hardly damaged by strong alkali and strong acid chemicals. Furthermore, it is superior in adhesion to various materials such as silicon, ceramics and metals (e.g., aluminum). Therefore, it is widely used in various fields.
Horinouchi et al. (1990) Technical Digest of the 9th Sensor Symposium, pp. 19-22 discloses a silicon wafer that is covered with a coating resin, except the front surface thereof (see FIG. 2).
Japanese Patent Second Publication JP-B-52-44703 discloses a method of producing a semiconductor device that has a npn transistor embedded in the surface of a substrate thereof.
In this method, at first, the substrate is irradiated with gas plasma such as an oxygen or argon plasma so as to decrease the current amplification factor of the transistor to a predetermined value. Then, the substrate is subjected to a heat treatment so as to increase the current amplification factor to the desired value.
Japanese Patent Second Publication JP-B-60-11458 discloses a method of producing a semiconductor device, in which a silicone resin is used, particularly as an insulating layer's material. In this method, at first, aluminum is deposited on a semiconductor's substrate 11. Then, the deposited aluminum is etched to form a first layer wiring 12 on the substrate 11. Then, a silicone resin layer 13 having a thickness of about 100 nm is formed so as to cover the first layer wiring 12 therewith (see FIG. 2(a)). Then, the silicone resin layer 13 is optionally heated to harden the same. Then, a patterning mask 17 such as photoresist or phosphosilicate glass (PSG) is formed on the silicone resin layer 13 (see FIG. 2(b)). Then, the exposed portion of the silicone resin layer 13 is oxidized to silicon oxide 16 by irradiating the semiconductor substrate 11 with an oxygen plasma for about 15 min under an oxygen gas pressure of 1 Torr at a power of 100 W (see FIG. 2(c)). Then, the thus formed silicon oxide 16 is removed by etching with a hydrofluoric acid containing solution (see FIG. 2(d)).
If the method according to JP-B-60-11458 is applied to remove a silicone resin film for protecting a semiconductor substrate, which film, has a much greater thickness (at least 10 .mu.m) than that (about 100 nm) of JP-B-60-11458, it is very difficult to completely oxidize the silicone resin film to silicon oxide, even if the power and the period of time of the irradiation of JP-B-60-11458 are increased to a great extent. If a silicone resin film is irradiated with the oxygen plasma under the same conditions as those described in JP-B-60-11458, a transistor embedded in the surface of a semiconductor substrate may be greatly lowered in the current amplification factor, as shown in FIG. 3 of JP-B-52-44703. Furthermore, when a silicone resin which is reinforced with filler is used for increasing the strength of a semiconductor substrate and thus for forming a diaphragm of semiconductor pressure sensor, it may be impossible to completely oxidize the silicone resin layer to silicon oxide by the method of JP-B-60-11458.

Method of producing semiconductor device


A system comprises a plurality of acoustic transmitters, mounted inside the streamers, adapted to transmit broadband signals having low cross-correlation between the signals of different transmitters; a plurality of acoustic receivers, mounted inside the streamers, adapted to receive the signals from the transmitters; at least one processor adapted to cross-correlate the signals received at the receivers with copies of transmitter signals to determine identities of the transmitters of the received signals and to determine travel times of the received signals; and a main processor adapted to convert the travel times to distances between the identified transmitters and the receivers and to determine relative positions of the streamers from the distances.

1. Field of the Invention
This invention relates generally to the field of geophysical prospecting. More particularly, the invention relates to the field of marine seismic data acquisition.
2. Description of the Related Art
To perform a three-dimensional (3D) marine seismic survey, a plurality of marine seismic streamers are towed at a preset depth, typically between 4 and 25 meters, behind a surface survey vessel. Each seismic streamer, also referred to as a streamer cable, is typically several thousand meters long and contains a series of seismic sensors and associated analog-to-digital signal converter electronics distributed along the streamer length. The streamer cables comprise a series of individual segments, called streamer sections, each typically 75 to 200 meters long. The survey vessel also tows one or more seismic sources, for example air guns or water guns, but most commonly consisting of arrays of air guns. Acoustic signals generated by the seismic sources are transmitted down through the water column and several more kilometers down into the subterranean formations. Parts of the signals are reflected from the interfaces between various strata, due to differences in the acoustic impedance between different rock formations. The acoustic signals reflected from the subterranean formations are detected by the seismic sensors located within the streamers. The acquired seismic signals are digitized and sent via a main telemetry link to the survey vessel for data processing onboard or later processing onshore. The processed data is used for estimating the subterranean formation structure and possible hydrocarbon content.
FIG. 1A illustrates a top schematic view of an ideal case, with no cross-currents, of a 3D marine seismic survey using towed streamers. A seismic survey vessel 1 tows a relatively small seismic tow system which comprises an active source consisting of three air gun arrays 2, and a spread of four streamer cables 3. The streamer cables 3 extend from streamer separation doors (also referred to as deflectors) 4 at the front of the spread to tail buoys 5 at the rear. In this ideal case, the streamer cables 3 all extend behind the vessel 1 in unrealistically straight and equally spaced lines parallel to the vessel track and to each other. FIG. 1B illustrates a top schematic view of a more realistic case of a 3D marine seismic survey using towed streamers, showing the typical effects of cross-currents on the streamer spread. The separations between the streamers 3 are no longer constant and the positions of the tail segments deviate from the vessel track. This deviation effect is called "feathering". The tail segments of the streamers can, in some survey areas, deviate significantly from the vessel track due to the cross-currents along the tow spread.
For correct seismic imaging of the sub-bottom beneath the survey area, it is important to accurately determine the position of both the air gun sources and the seismic receivers. The seismic sources are towed relatively closely behind the survey vessel and are easier to control than the streamer spread. Streamer spreads typically consist of 8 to 12 independently towed streamer cables, with each streamer being 3 to 8 kilometers long. However, the trend is to deploy even more and longer streamers, such as up to 20 streamers of approximately 12 kilometers length. Accurate determination of streamer positions is also important in avoiding high risk operational situations such as streamer tangling. The tangling can be caused by strong water currents in the sea when more than one cable is hooked up and connected. Resolving such tangling scenarios is complex and may expose the seismic crew to hazardous in-sea operations, in addition to being quite costly.
Methods for determining streamer positions have included the use of devices such as Global Positioning System (GPS) receivers, magnetic compasses (also referred to as magnetic heading sensors), acoustic transmitters, conventional streamer hydrophones, or acoustic receivers specifically dedicated to the position-determining task.
U.S. Pat. No. 4,231,111, "Marine Cable Location System", issued to Walter P. Neeley on Oct. 28, 1980, discloses a method for determining streamer positions that distributes magnetic compasses along the streamer cables at regular intervals and employs the heading information from these compasses to model the shape and orientation of each cable. However, the externally-mounted compasses are sometimes lost due to streamer entanglement or other impact situations, and the compasses create flow noise on neighboring seismic sensors. Additionally, the compasses are charged by batteries which need to be replaced at certain intervals and the compasses have to be re-calibrated in the factory after any repairs or changes.
U.S. Pat. No. 5,761,153, "Method of Locating Hydrophones", issued to Vassilis N. Gikas, Paul A. Cross, an Asiama Akuamoa on Jun. 2, 1998, discloses a method for determining streamer positions that employs both magnetic compasses and acoustic transceivers, including both transmitters and receivers. The transmitters and receivers, just as the magnetic compasses, are externally attached to the streamer cables and seismic sources, powered by batteries and communicate via inductive coils located within the streamers. Coded ultrasound signals are transmitted between the transceivers. The transceivers measure distances between transmitters and receivers and enable both the shape of the towed arrays to be determined and the relative positions of the seismic sensors to be estimated. In methods exemplified by Gikas et al. '153, the transmitters and receivers are only placed at the front, center and tail of the streamer spread, due to the high cost of the acoustic transceivers. The magnetic compasses are then used to determine the streamer positions between the transceiver locations. This method still has the problems associated with externally mounted magnetic compasses, as discussed above with respect to Neeley '111.
U.S. Pat. No. 4,992,990, "Method for Determining the Position of Seismic Streamers in a Reflection Seismic Measuring System", issued to Jan-Åge Langeland, Stein ÅSheim, Bjorn Nordmoen, and Erik Vigen on Feb. 2, 1991, discloses a method for determining streamer positions that deploys acoustic transceivers throughout the complete streamer spread. Langeland et al. '990 employs acoustic transceivers positioned on the seismic vessels, tail buoys, a float towed near the front of the streamers, the stretch sections at the front and rear of the streamers, and possibly in the active sections of the streamers. The transceivers operate in the frequency band of 25 to 40 kilohertz (kHz). Starting with two known positions, preferably on the tow vessel and the float, the positions of the other transceivers are determined by trilateration of the transit times (and hence the distances) between the transceivers to form a solvable triangular network. However, employing the seismic acquisition receivers to determiner streamer positions can cause problems when some of the seismic acquisition receivers are unavailable, due to mechanical or electrical failure in the streamers or elsewhere in the tow system. Additionally, this method has the problems associated with externally mounted transceivers, as in Gikas et al. '153 above.
U.S. Pat. No. 4,912,682, "Point Location Determination At or Close to the Surface", issued to John P. Norton, Jr., Michael A. Hall, and Ian N. Court on Mar. 27, 1990, discloses a system in which ultrasonic sonar transmitters are positioned along a streamer, preferably at 300 meter intervals, and seismic receivers are positioned along a streamer, preferably at 100 meter intervals, so that there are three times as many receivers as transmitters. The transmitters emit a unique tone burst or series of tone bursts or a continuously varying tone as in a chirp signal. The signal is transmitted in the 50 to 150 kHz band. The receivers are time-gated to only register the signal during a set time period, to limit the number of receivers apportioned to each transmitter, preferably to seven. The elapsed time for each transmitter-receiver pair is converted to distance by multiplying by the local speed of sound in water, which is assumed constant. The positions of the front of each streamer are presumed known and the positions of the transmitters and receivers are solved sequentially down the streamer lengths by a variation of coordinates technique. In this technique, a set of equations in the additive correction terms is reduced to normal equations by least squares and then solved. From the relative spacing between transmitters and receivers, their relative positions can be determined. However, employing the seismic acquisition receivers to determine streamer positions and attaching the transmitters and receivers externally to the streamer leads to the same problems discussed in Langeland et al. '990, above.
U.S. Pat. No. 6,839,302 B2, "Acoustic Emitters for Use in Marine Seismic Surveying", issued to Peter Austad and Rolf Rustad on Jan. 4, 2005, discloses a method that avoids the drawbacks of externally-mounted equipment by putting the transmitters or receivers in special sections that can be inserted between conventional streamer sections. Austad et al. '302 describes an acoustic emitter that can be inserted between adjacent streamer sections. The emitter comprises an annular housing containing an annular piezoelectric emitting element, which is protected from bending by surrounding flexible barrel stave members. The emitter is adapted to operate in a frequency range up to 10 kHz. However, locating the transmitters in additional insert sections between the streamer sections is expensive and labor intensive.
A problem particular to determining the positions of towed seismic streamers with transmitters and receivers is keeping track of which transmitter's signal is being detected by which receiver at any given time. U.S. Pat. No. 4,187,492, "Device for Determining the Relative Position of Elongate Members Towed behind a Ship", issued to Robert Delignieres and Mareil Marly on Feb. 5, 1980, discloses a method for employing different frequencies for different transmitters. Delignieres et al. '492 describes a system in which acoustic wave transmitters are positioned along a first streamer and acoustic pulse receivers are positioned along a second streamer. Each transmitter transmits at a different frequency and each receiver receives signals from only one transmitter. The system includes a telemetry system for determining travel time intervals of the acoustic pulses between transmitters and receivers and measuring the relative distances from these travel times. The transmitters and receivers primarily comprise a transducer six cylinders of piezoelectric ceramic of six different lengths vibrating in longitudinal mode at six different frequencies. Delignieres et al. '492 gives as an example six frequencies in the range of 20 to 100 kHz. However, employing different frequencies to distinguish the transmitters generally increases the complexity and expense of both the transmitters and the receivers.
U.S. Pat. No. 6,697,300 B1, "Method and Apparatus for Determining the Positioning of Volumetric Sensor Array Lines", issued to Michael D. Holt on Feb. 2, 2004, discloses a method in which each transmitter transmits a distinguishable signal, even though the transmitters and sensors are of identical design, all operating at the same frequency. Holt '300 describes a system which comprises transmitters (including ceramic transducers), sensors (hydrophones) for receiving seismic reflections of the transmitters' signals from objects of interest, and detectors for receiving the transmitters' signals directly. The detectors determine travel times in terms of intervals of clock periods, and hence distances, between the streamers. The transmitters employ code division multiple access type pseudo-random numbers to uniquely identify the signals coming from each transmitter. The signals sent by the transmitters to the streamer-positioning detectors modulate a carrier wave outside the acoustic analysis band of the signals received by the object-positioning sensors, since Holt '300 teaches a system for sonar detection of enemy vessels which must be undetected by the other vessels. In the case of seismic acquisition surveys, this requirement would result in a transmitter carrier wave above the seismic acquisition band. These higher frequency signals suffer from higher attenuation, thus degrading the resolution required for positioning long streamer arrays.
U.S. Pat. No. 5,668,775, "Methods for Determining the Position of Seismic Equipment, and Applications of the Methods", issued to Kjell Hatteland on Sep. 6, 1997, discloses a method employing acoustic transmitters between streamer section segments and conventional seismic receivers (hydrophones) located inside the streamers. Both power and communication to these transmitters go through the streamer harness. The transmitters operate at low frequencies, in the approximate range of 1 Hertz (Hz) to 1 kHz, encompassing the seismic frequency range. The transmitters generate a spread spectrum signal as an orthogonally encoded signal sequence with an unambiguous top in the form of a prominent peak in the signal's autocorrelation function. Cross-correlating the signal received by a receiver with the orthogonally encoded signal sequence of the transmitted spread spectrum signal allows the determination of a time difference between the detection of the signal by different receivers. This time difference, in turn, allows the determination of the distance between individual transmitters and receivers, based on a known in-line distance between receivers. A high number of transmitter-receiver combinations are used to determine a network which then gives the seismic equipment's geometrical configuration. However, in Hatteland 3 775, the seismic receivers are employed both for determining streamer positions as well as conventional seismic acquisition, instead of employing separate systems of dedicated receivers, leading to the same problems discussed above in Norton, Jr. et al. '682 and Langeland et al. '990.
The previously described methods for determining the positions of streamers contain a number of problems. In systems employing magnetic compasses, as in Neeley '111 and Gikas et al. '153, compass headings are referred to magnetic north, and knowledge about the local magnetic variation (declination) is necessary. The effect of magnetic storms and local anomalies can only partly be corrected for. Due to the sparse sampling along the cable and lack of information about how the streamer behaves between the compass locations, the positioning accuracy is not precise. This lack of precision is especially important when lateral steering devices used to control the cross-line position of the streamer cables are placed between the compass positions. Because compass readings are influenced by wave motion caused by weather conditions, the compass readings are filtered over time, with the result that the values used in the computations of streamer positions have a significant time lag.
Employing externally-mounted transceivers, either transmitters or receivers, as in Gikas et al. '153, Langeland et al. '990, and Norton, Jr. et al. '682, has several drawbacks. During streamer deployment and retrieval modes, attaching and removing the transceivers so that the streamers can be spooled directly on and off winches onboard the survey vessel requires considerable operational time, which is very expensive. Externally-attaching the transceivers (or any other equipment, such as magnetic compasses) to the streamer cables increases tow drag on the streamer and increases the noise in the detected seismic signals. The transceivers are also exposed to impact and thus transceivers are lost from time to time. In addition, the batteries have to be replaced at regular intervals. Because of the high frequencies used for the acoustic ranging, the performance may be degraded in hostile acoustic environments.
Locating transmitters or receivers in dedicated streamer inserts; between streamer sections, as in Austad et al. '302, is expensive and labor intensive. Additionally, both data redundancy and quality may be limited because of the limitation on spacing of the transceivers.
Employing transmitters designed to transmit at different frequencies, as in Delignieres et al. '492, may increase the cost of both the transmitters and receivers. Employing transmitters designed to transmit at higher frequencies, as in Holt '300, leads to signals which attenuate too rapidly over longer distances. This attenuation reduces the resolution at the longer distances employed in positioning long streamer arrays than in the shorter streamer arrays employed in detecting vessels, as in Holt '300.
Employing the seismic data acquisition receivers, instead of separate dedicated receivers, to determine steamer positions, as in Langeland et al. '990, Norton, Jr. et al. '682, and Hatteland '775, leads to problems. The acoustic position-determining network may be significantly degraded if the seismic acquisition receivers are not available on some streamers. Receiver unavailability may occur during streamer failure, maintenance or system testing.
Finally, the inability to make inline distance measurements, as in Norton et al. '682, leads to lack of precise knowledge of the distance between the transmitters and receivers when the streamer is under tow, which in turn, leads to lack of accurate knowledge of the amount of stretching of the streamer under tension. This lack of knowledge degrades the streamer position-determining accuracy.
Thus, a need exists for an improved method for determining positions of towed marine seismic streamers.

System and method for determining positions of towed marine seismic streamers


The present disclosure provides for compounds useful for the treatment or prevention of disorders with an etiology associated with or comprising excessive cytokine or chemokine release. The compounds are also useful for the treatment of cancer, inflammatory disorders and disorders associated with an increased stability or translation of mRNA which has an mRNA instability sequence.

A number of compounds have been described in the literature that can modulate mRNA function. One of the first examples of such an effect was Radicicol analog A, which was shown to induce a rapid mRNA degradation of IL-1β, TNFα, IL-6 and Cox-2 in THP-1 cells. It was then demonstrated that the effect of this compound is mediated by the presence of AU-rich elements (ARE) in the target mRNA 3′UTRs. Furthermore, other molecules are used therapeutically in a variety of disease areas are known to affect mRNA stability/translatability such as paclitaxel, cyclosporin A, thalidomide and glucocorticoids.


A process for catalytic reforming of feed hydrocarbons to form aromatics, comprising contacting the feed, under catalytic reforming conditions, with catalyst particles disposed in the tubes of a furnace, wherein the catalyst is a monofunctional, non-acidic catalyst and comprises a Group VIII metal and zeolite L, and wherein the furnace tubes are from 2 to 8 inches in inside diameter, and wherein the furnace tubes are heated, at least in part, by gas or oil burners located outside the furnace tubes.

The present invention relates to catalytic reforming using a catalyst comprising zeolite L. More particularly, the present invention pertains to use of such catalyst in a conventional gas or oil fired furnace.
Reforming embraces several reactions, such as dehydrogenation, isomerization, dehydroisomerization, cyclization and dehydrocyclization. In the process of the present invention, aromatics are formed from the feed hydrocarbons to the reforming reaction zone, and dehydrocyclization is the most important reaction.
U.S. Pat. No. 4,104,320 to Bernard and Nury discloses that it is possible to dehydrocyclize paraffins to produce aromatics with high selectivity using a monofunctional non-acidic type-L zeolite catalyst. The L zeolite based catalyst in '320 has exchangeable cations of which at least 90% are sodium, lithium, potassium, rubidium or cesium, and contains at least one Group VIII noble metal (or tin or germanium). In particular, catalysts having platinum on potassium form L-zeolite exchanged with a rubidium or cesium salt were claimed by Bernard and Nury to achieve exceptionally high selectivity for n-hexane conversion to benzene. As disclosed in the Bernard and Nury patent, the L zeolites are typically synthesized in the potassium form. A portion, usually not more than 80%, of the potassium cations can be exchanged so that other cations replace the exchangeable potassium.
Later, a further important step forward was disclosed in U.S. Pat. Nos. 4,434,311; 4,435,283; 4,447,316; and 4,517,306 to Buss and Hughes. The Buss and Hughes patents describe catalysts comprising a large pore zeolite exchanged with an alkaline earth metal (barium, strontium or calcium, preferably barium) containing one or more Group VIII metals (preferably platinum) and their use in reforming petroleum naphthas. An essential element in the catalyst is the alkaline earth metal. Especially when the alkaline earth metal is barium, and the large-pore zeolite is L-zeolite, the catalysts were found to provide even higher selectivities than the corresponding alkali exchanged L-zeolite catalysts disclosed in U.S. Pat. No. 4,104,320.
These high selectivity catalysts of Bernard and Nury, and of Buss and Hughes, are all "non-acidic" and are referred to as "monofunctional catalysts". These catalysts are highly selective for forming aromatics via dehydrocyclization of paraffins.
Having discovered a highly selective catalyst, commercialization seemed promising. Unfortunately, that was not the case, because the high selectivity, L-zeolite catalysts did not achieve long enough run length to make them feasible for use in catalytic reforming. U.S. Pat. No. 4,456,527 discloses the surprising finding that if the sulfur content of the feed was reduced to ultra low levels, below levels used in the past for catalysts especially sensitive to sulfur, that then long run lengths could be achieved with the L-zeolite non-acidic catalyst. Specifically, it was found that the concentration of sulfur in the hydrocarbon feed to the L-zeolite catalyst should be at ultra low levels, preferably less than 100 parts per billion (ppb), more preferably less than 50 ppb, to achieve improved stability/activity for the catalyst used.
It was also found that L zeolite reforming catalysts are surprisingly sensitive to the presence of water, particularly while under reaction conditions. Water has been found to greatly accelerate the rate of deactivation of these catalysts. U.S. Pat. No. 4,830,732 discloses the surprising sensitivity of L zeolites to water and ways to mitigate the problem.
U.S. Pat. No. 5,382,353 and U.S. Pat. No. 5,620,937 to Mulaskey et al. disclose a zeolite L based reforming catalyst wherein the catalyst is treated at high temperature and low water content to thereby improve the stability of the catalyst, that is, to lower the deactivation rate of the catalyst under reforming conditions.
Also, several patents and patent applications of RAULO (Research Association for Utilization of Light Oil) and Idemitsu Kosan Co. have been published relating to use of halogen in L-zeolite based monofunctional reforming catalysts. Such halogen containing monofunctional catalysts have been reported to have improved stability (catalyst life) when used in catalytic reforming, particularly in reforming feedstocks boiling above C.sub.7 hydrocarbons in addition to C6 and C7 hydrocarbons. In this regard, see EP 201,856A; EP 498,182A; U.S. Pat. No. 4,681,865; and U.S. Pat. No. 5,091,351.
EP 403,976 to Yoneda et al., and assigned to RAULO, discloses the use of fluorine treated zeolite L based catalysts in small diameter tubes of about one-inch inside diameter (22.2 mm to 28 mm in the examples). Heating medium proposed for the small tubes were molten metal or molten salt so as to maintain precise control of the temperature of the tubes. Accordingly, EP 403,976 does not teach the use of a conventional type furnace or conventional type furnace tubes. Conventional furnaces for catalytic reforming have tubes of usually three or more inches in inside diameter (76 mm or more), whereas EP 403,976 teaches that using tubes having an inside diameter greater than 50 mm is undesirable. Also, conventional furnaces are heated using gas or oil fired burners.
Typical catalytic reforming processes employ a series of conventional furnaces to heat the naphtha feedstock before each reforming reactor stage, as the reforming reaction is endothermic. Thus, in a three-stage reforming process, the overall reforming unit would comprise a first furnace followed by a first-stage reactor vessel containing the reforming catalyst (over which catalyst the endothermic reforming reaction occurs); a second furnace followed by a second-stage reactor containing reforming catalyst over which the reforming reaction is further progressed; and a third furnace followed by a third-stage reactor with catalyst to further progress the reforming reaction conversion levels.
For example, U.S. Pat. No. 4,155,835 to Antal illustrates a three-stage reforming process, with three furnaces (30, 44, 52) and three reforming reactors (40, 48, 56) shown in the drawing in Antal. Example reforming reactors used according to the prior art are shown, for instance, in U.S. Pat. No. 5,211,837 to Russ et al., particularly the radial flow reactor shown in FIG. 2 of Russ et al.
In some catalytic reforming units, as many as five or six stages of furnaces followed by reactors are used in series for the catalytic reforming unit.

Zeolite L catalyst in conventional furnace


A specification of a client-side user interface behavior for a view of a computer application is received from a representative of an organization. The received specification is stored. A request for content of the view is received via a network from the computer application associated with a user that belongs to the organization. The received specification is identified as being associated with the requested content of the view. The requested content of the view and an identifier of the identified specification of the client-side user interface behavior are provided via the network. The computer application utilizes the received identifier of the identified specification of the client-side user interface behavior to modify the view of the computer application.

Cloud-based services allow customers to store, access, and manage small to large volumes of customer data that can be accessed remotely from a variety of clients. The stored customer data can be a diverse assortment of content data including information on incident reports, hardware and software assets, and employee timesheets, among others. The content data can be hosted and viewed by clients of the cloud-based service using a custom computer application, such as a mobile application. The combination of a client application and a cloud-based service allows customers to interact with the customer data, for example, by viewing and modifying the data. The cloud-based nature of the combination allows the customer data to be accessed with a high level of operational performance but with limited management requirements required from the customer and the ability to scale as demand changes.

Dynamic client-side update of a view of an application


A golf tee measuring device and divot repair tool is provided for measuring the length of a golf tee, repairing divots, and housing a marker, the device comprising a housing defining an open aperture, a positioning slot within which a button travels, and an interior recess. The device further comprises a lower component having two extrudable prongs for repairing divots, the lower component defining a guide track recessed into an interior surface.

Field of the Invention
This invention relates to the game of golf and in particular, to a device measuring the length of a golf tee and replacing divots.
Description of the Related Art
A golfer's grip, stance, pivot, and follow-through all affect a golfer's work to achieve a consistent and ideal golf swing. The vertical point at which the face of the driver strikes the ball is also important. At the ideal striking point, a clubface makes initial contact with the midpoint of a golf ball at the driver's "sweet spot," or a portion of the clubface designed to provide the straightest drive. Initial contact with the ball above or below its center or above or below the clubface's sweet spot can result in excess spin, and a less accurate drive.
Golf tees are used by golfers to elevate the golf ball above the ground and facilitate contact at the ideal striking point. Conventional tees are typically made of wood or plastic, have a stake portion with a pointed end for insertion into the turf, and have a cupped end for supporting a ball. The optimal depth for insertion to facilitate the ideal striking point at a club's "sweet spot" is known to be the depth that allows the bottom of the club head to rest on the turf while the top of the club head is even with the center of the ball. Typically, the ordinary golfer inserts the tee into the ground relying upon his/her eyesight and best judgment to insert the tee into the turf at approximately the optimal depth.
The prior art teaches tee shafts having, for example lines, notches or a stopping mechanism, such as a removable or non-removable horizontal member that makes contact with the ground when the shaft is inserted to the proper depth.
A second problem with conventional tees, and one not addressed by the prior art, is the actual method of insertion depth estimation. Thus, while markings on a shaft may allow a golfer to insert his tee at the same depth each time, this does not guarantee that the depth consistently used is the optimal one. The fact that different tees differ in their overall height, and are marked in differing fashions, adds further complication. There exist no devices for efficiently inserting a tee into the ground with a predetermined length of shaft above the ground surface.
Although golfers are careful about positing their tees in the ground, tees often vary in their length, size and strength. A drawback of golf tees in the prior art are that they are not designed to allow the golfer to place the golf tee in the ground at the same depth every time, and the golfer cannot maintain the same body position every time. The golfer has to adjust his or her hands up or down the golf shaft to compensate for the varying height of the golf tee. Golfers' inability to judge the length of a tee and consistently place the tee at the same height distracts from a golfer's ability to concentrate on those factors mentioned above that require focus and practice. Problems with depth placement lead to loss of range and accuracy.
Additionally, when the ball lands on the green, it leaves a divot mark on the green. The golfer is expected to fix the divot on the green and divot tool is typically used for this green repair. Typically, these divots repaired as a matter of etiquette by the golfers. Divot repair tools combined with other golf devices do not exist in efficient form in the prior art. Golfers additionally lack a device for holding a marker for marking the position of balls on a course or ground surface.
There exists a need in the art for a device that accurately measures the height of golf tees above ground, that allows a golfer to replace divots, and holds a marker like a coin. Current methods and apparati are not effective.

Golf tee measuring apparatus and divot repair tool


A terminal is disclosed including a processor that generates a sequence for a demodulation reference signal based on a symbol index and a slot index. The terminal further includes a transmitter that transmits the demodulation reference signal. In other aspects, a radio communication method and a base station are also disclosed.

In the UMTS (Universal Mobile Telecommunications System) network, the specifications of Long Term Evolution (LTE) have been drafted for the purpose of further increasing high speed data rates, providing lower latency, and so on (see Non-Patent Literature 1). In addition, successor systems of LTE are also under study for the purpose of achieving further broadbandization and increased speed beyond LTE (referred to as, for example, "LTE-A (LTE-Advanced)," "FRA (Future Radio Access)," "4G," "5G," "5G+(plus)," "NR (New RAT (New Radio Access Technology))," "LTE Rel. 14," "LTE Rel. 15 (or later versions)," and so on).
In existing LTE systems (for example, LTE Rel. 13 or earlier), downlink (DL) and/or uplink (UL) communications are carried out, using a transmission time interval (TTI) (also referred to as "subframe" and so on) of 1 ms. This TTI of 1 ms is a unit of time to transmit one data packet that is channel-encoded, and is a processing unit in scheduling, link adaptation, retransmission control (HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledge)), and so on. The TTI of 1 ms includes two slots.
In the existing LTE systems, a radio base station demodulates a UL channel (including a UL data channel (for example, a PUSCH (Physical Uplink Shared Channel)) and/or a UL control channel (for example, a PUCCH (Physical Uplink Control Channel))), based on results of channel estimation of a demodulation reference signal (DMRS).
In the existing LTE systems, a user terminal multiplexes a UL channel and a DMRS and transmits the multiplexed result within the TTI of 1 ms. Within the TTI of 1 ms, a plurality of DMRSs of different layers of the same user terminal (or different user terminals) are orthogonally multiplexed by using cyclic shift (CS) and/or orthogonal spreading code (for example, orthogonal cover code (OCC)).

Terminal, radio communication method, and base station


A system and method for measuring the movement of one or more limbs of an infant using a video system for the purpose of determining whether the infant suffers from or is at risk of suffering from a medical condition such as cerebral palsy.

Over the past two decades, the incidence of preterm births has increased dramatically. Technological advances in the medical and health sciences have increased the survivability of these preterm infants. The increase in survival, however, has been accompanied by an increase in the incidence of long-term complications associated with premature births such as cerebral palsy (CP), with approximately 10% of preterm infants developing CP. Early diagnosis of CP and other motor abnormalities may enable clinicians to implement early interventions and provide an improved quality of life. Diagnosis is usually made between several months and 2 years of age.
Attempts have been made to develop techniques to be able to detect movement patterns predictive of neurological dysfunction such as CP. One conventional tool for diagnosis of CP is the physician's neurological exam. This exam focuses on the infant's reflexes but places little importance on spontaneous movements. It has been found however that spontaneous movements have a higher predictive value for the development of cerebral palsy compared to reflexive movements. As a result, early diagnosis of CP is often unreliable.
Another tool for diagnosis of CP is the so-called General Movements Assessment (GMA), a technique focused on an infant's spontaneous movements. The GMA is an observational assessment that judges the quality of infant movements and identifies key movements which are markers of neurological dysfunction. General Movements (GMs) of the infant are defined as movements involving the entire body of the infant. Specifically, GMs are a distinct movement pattern carried out spontaneously without external stimulation and seen in fetuses of nine (9) weeks gestational age until about twenty-one (21) weeks post-term. In normal infants, these movements are elegant, smooth and variable in sequence, intensity and speed with a clear beginning and end. The GMA identifies cramped synchronized general movements (CSGMs) as one type of abnormal movement. These movements are rigid in nature and involve an infant's limbs moving in synchrony, with the limb muscles contracting and relaxing almost simultaneously. The presence of cramped synchronized movements has been shown to be highly predictive value for the development of cerebral palsy.
Conventional approaches to analyzing infant movement involve directly observing or videotaping subjects for variable periods of time and then qualitatively analyzing their movements using validated movement scales. One problem with video/direct observation is observer fatigue. One study focusing on natural patterns of physical activity in 6-8 year old children indicated that with a 3-second observation protocol, a typical observer needs a substantial break after about 20 minutes. Moreover, attempting to quantify activity of four (4) limbs in a preterm infant by direct observation is a challenging task, even for the most adept observer. In addition, the clinician must have extensive training in order to accurately carry out these techniques. The time commitment for appropriate training is not always feasible for the neonatal physician or occupational therapist.

System for evaluating infant movement using gesture recognition

The Regents of the University of California


Data protection operations including verification operations are disclosed. Objects written to a cloud tier are verified without reading the objects out of the cloud. A translation map is used that allows a cloud verifier engine to compare a checksum of an object generated at an local tier with a checksum of the object as stored in the cloud tier. Mismatches are identified and corrective actions can be taken by reconstructing and rewriting the object to the cloud tier. Garbage collection may be prevented from reclaiming data associated with objects that have not been verified.

Cloud storage is commonly used for a wide variety of purposes. Cloud storage, for example, is often used by data protection applications to store backups of production data. In addition, data protection systems may also use cloud storage for deduplication purposes. For example, data backed up in a local storage, which constitutes an example of a local tier, may be moved to cloud storage, which constitutes an example of a cloud tier.
When data is moved to the cloud tier from the local tier, the application moving the data relies on the cloud tier to ensure that the data is successfully written to the cloud storage. However, data can be corrupted for a variety of reasons. For example, data may be corrupted when transmitted over the wire. Writes can be dropped or written incorrectly in the cloud storage due to software bugs, hardware issues, and the like.
When data is written incorrectly, the error may not be discovered until the data is accessed again at some future time. The error may not be detected for weeks, months, or years. By the time the error is detected, it may be difficult or impossible to perform corrective actions.
In the local tier, this problem of verifying the writes can be solved by performing a read-verify on write. Every block of data that is written is read back and verified to ensure validity and correctness. If an error or issue is determined, the data can be written again or the error can be flagged such that the error is discovered closer to their point of origin.
In the cloud tier, this approach is not feasible at least because the latency and cost involved in doing a read-verify from the cloud tier is cost prohibitive. For example, if 100 Gigabytes (GB) of objects are written to the cloud tier, the application must perform 100 GB of reads from the cloud tier to verify that the objects were written correctly. Cloud data egress is costly and this method is too expensive.
In another example, the cloud storage provider may support cloud tier verification via checksums that are provided by the client. The object being uploaded is only created in the cloud tier when the checksum provided by the client matches the checksum determined by the cloud storage software for the received data. Although this may identify errors that occurred during network transfer, this does not detect errors that may occur while writing the object to the cloud storage disks.
Cloud storage providers may also generate a checksum of the object and store the checksum in the object's metadata. However, this checksum is typically generated before the object is written to disk. Consequently, this still does not detect errors that may arise when the data is written to disk. Further, there is no current way to verify the data other than reading from the cloud tier, which is expensive as previously discussed.
In addition, even if cloud objects are found to be incorrect, there is no guarantee that the local data copy is still available. Often, the local tier data is reclaimed through garbage collection after the object is committed to the cloud tier. This makes it difficult to correct the objects stored incorrectly in the cloud tier.

Method to enhance the data invulnerability architecture of deduplication systems by optimally doing read-verify and fix of data moved to cloud tier


Apparatus for measurement of light waves with an unbalanced optical interferometer. The apparatus consists of waveguides on a flat substrate material characterized by direction-dependent thermal expansion. Thermal compensation is achieved without active regulation by a predetermined spatial arrangement and length ratio of the light paths so that the optical lengths of the two waveguides change by precisely the same amount. As a result, the optical path difference is independent of temperature changes.

1. Field of the Invention
The present invention relates to apparatus for the interferometric measurement of light waves. More particularly, the invention pertains to apparatus of such sort fabricated in integrated optics on an anisotropic substrate.
2. Description of the Prior Art
Unbalanced optical interferometers comprise devices in which a light beam is split into at least two partial light beams. After the beams traverse defined, unequal paths, they are recombined into a single beam. As a result of interference, the intensity of the recombined beam is a function of the phase difference between the two partial light beams. Unbalanced interferometers are employed, for example, for light source wavelength stabilization, wavelength measurement, frequency analysis of light and demodulation of frequency-modulated optical signals.
A prerequisite for proper operation of such a device is maintenance of the selected optical path difference (determined as refractive index x path difference). Specifically, length and refractive index changes due to temperature change must not influence the optical path difference. In this regard, it is known to temperature-control the interferometer (that is, to actively control the temperature) to maintain it at the same temperature at all times. It is also known to construct beam-optical interferometers entirely of material of extremely low thermal expansion qualities such as Zerodur.
Current research is devoted to miniaturization and integration of optical and optoelectronic components. In integrated optics components, the light is guided in waveguides, modulated, superposed and detected. The structures consisting of waveguides and electrodes are applied to the surface of transparent substrates such as lithium niobate, various semiconductors, glass and garnet. Most of the materials employed in integrated optics (IO) are synthetic monocrystals. In such materials, thermal expansion and the thermal change of refractive index are non-negligible and of differing magnitudes in the various crystal directions. Accordingly, it has not been possible to construct an unbalanced, temperature-compensated interferometer in integrated optics by employing known, conventional techniques. Temperature control of the component is indeed conceivable; however, in most applications, it is not practicable due to the required energy consumption and the required broad temperature range.

Integrated optical apparatus for the interferometric measurement of light waves


A system, comprises an implant including an outer sleeve and a head element, the outer sleeve extending longitudinally and including a channel extending therethrough, the head element including a shaft portion and a bone-engaging portion, the shaft portion received within the channel of the outer sleeve and longitudinally movable relative thereto and a clip device removably assembled with the implant to hold the outer sleeve and the head element in a desired position relative to one another, the clip device including a body extending longitudinally along with a separation portion connected to a proximal end of the body via a releasable connection to engage the proximal end of the outer sleeve and a spacer portion connected to the proximal end of the body to releasably engage a portion of the shaft portion between a proximal end of the bone-engaging portion and the distal end of the outer sleeve.

Bone fractures are often treated with screws or other fixation devices inserted into the bone to stabilize portions thereof once they have been brought into corrective alignment. In particular, hip fractures (e.g., trochanteric fractures of the proximal femur) may be treated using proximal femoral nail systems including the insertion of an intramedullary nail into a medullary cavity of a long bone such as a femur and a subsequent insertion of an implant into the femoral head angled relative to the intramedullary nail (e.g., along an axis of the femoral neck). In some cases, the implant may include a telescoping femoral head component to permit compression of the bone during healing.

Break off spacer clip for trochanteric femoral nail telescoping head element


A microprocessor includes an architectural register and a non-architectural register, each having a plurality of condition code flags. A first instruction of the microarchitectural instruction set of the microprocessor instructs the microprocessor to update the plurality of condition code flags based on a result of the first instruction. The first instruction includes a field for indicating whether to update the plurality of condition code flags of the architectural or non-architectural register. A second instruction of the microarchitectural instruction set instructs the microprocessor to conditionally perform an operation based on one of the plurality of condition code flags. The second instruction includes a field for indicating whether to use the one of the plurality of condition code flags of the architectural or non-architectural register to determine whether to perform the operation.

Typically microprocessors include an architecturally visible register that includes condition code flags that are used by conditional instructions, such as a conditional branch instruction or a conditional move instruction. For example, in the x86 instruction set architecture, the EFLAGS register contains the Carry Flag (CF), Parity Flag (PF), Auxiliary Carry Flag (AF), Zero Flag (ZF), Sign Flag (SF), and Overflow Flag (OF), which are condition code flags that may be used by conditional instructions, and which are well-defined on pages 3-20 to 3-23 of the IA-32 Intel Architecture Software Developer's Manual, Volume 1: Basic Architecture, June 2006, which are hereby incorporated by reference in their entirety for all purposes. Examples of conditional instructions in the x86 architecture include the Jump If Condition Is Met (Jcc) instruction, the Conditional Move (CMOVcc) instruction, the Floating Point Conditional Move (FCMOVcc) instruction, the LOOPZ and LOOPNZ instructions, or the Set Byte on Condition (SETcc) instruction. Other instructions, i.e., an instruction earlier in program sequence to the conditional instruction, perform an arithmetic or logical operation to generate a result, and the microprocessor updates the condition code flags in the EFLAGS register based on the result. For example, a program may include a sequence of instructions that includes an ADD instruction followed later in the program by a JNZ instruction. The instruction set architecture specifies that the microprocessor updates the condition code flags in the EFLAGS register based on the result of the ADD instruction. For example, if the result of the ADD is zero, the microprocessor will set the ZF flag in the EFLAGS register. The JNZ instruction specifies a target address to which the microprocessor will jump if the ZF flag in the EFLAGS register is clear (i.e., not zero); otherwise, the microprocessor will fetch the next sequential instruction after the JNZ instruction.
Another feature of some modern microprocessors is that they include a microarchitecture that is different from the instruction set architecture, or architecture (also sometimes referred to as the macroarchitecture), of the microprocessor. This is typical of x86 architecture microprocessors. The architecture specifies the instruction set, register set, set of exceptions, and so forth that are visible to the assembly language programmer or compiler writer for the microprocessor. On the other hand, the microarchitecture specifies the internal organization of the microprocessor and includes details that are not visible in the architecture. For example, the microarchitecture specifies the various functional units of the microprocessor and their arrangement; whether the microprocessor is pipelined or non-pipelined, is scalar or superscalar, performs out-of-order execution, or performs speculative execution such as due to branch prediction and/or load hit prediction; the size and arrangement of cache memories; and so forth. Two different microprocessors may have the same architecture, yet have significantly different microarchitectures. In particular, in microprocessors that include microcode, the microarchitecture specifies its own instruction set that is different from the architecture instruction set and is typically not visible to the programmer. The instruction set of the microarchitecture is the set of instructions that the functional units of the microprocessor actually execute. The instructions of the architecture instruction set may be very complex and may be variable length. In contrast, the instructions of the microarchitecture instruction set typically are simpler than the instructions of the architecture instruction set, and popularly conform to the reduced instruction set computer (RISC) load-store and fixed instruction length paradigms. Furthermore, the number of registers of the microarchitecture register set is typically greater than the number of registers available in the architecture register set. For example, the microarchitecture may perform register renaming with its larger register set to improve performance.
Microprocessors that have distinct architectural and microarchitectural instruction sets include an instruction translator that translates architectural instructions (also referred to as macroinstructions) into instructions of the microarchitecture (microinstructions) that are dispatched to the execution units to be executed. Additionally, such microprocessors typically include microcode that implements some of the macroinstructions. The microcode is routines, or sequences, of microinstructions of the microarchitecture instruction set stored in a microcode memory of the microprocessor. When the instruction translator encounters a macroinstruction that is implemented in microcode, the instruction translator transfers control to a microsequencer, which fetches the microcode microinstructions from the microcode memory and dispatches them to execution units for execution. The microinstruction set includes instructions that update the architecturally-visible registers of the architecture in order to implement the macroinstructions. In particular, the microinstruction set includes instructions that update the architecturally-visible register that holds the condition code flags, such as the x86 EFLAGS register.
The present inventors have recognized that there are times when the microcode needs to include conditional instructions, such as conditional branch or conditional move instructions, that conditionally execute based on the results of arithmetic and logical instructions. For example, a microcode routine that implements a floating-point macroinstruction may include an arithmetic or logical microinstruction that generates an intermediate result followed by a conditional instruction that wants to know whether the intermediate result generated a carry or an overflow or a zero value or a negative or positive value, for example. However, the microcode cannot change the architectural condition code flags register unless the architecture specifies that the microcode-implemented macroinstruction updates the architectural condition code flags register, which is not true for many instructions of the x86 architecture, for example. For another example, a microcode exception handler may need to include an arithmetic or logical microinstruction that generates a result followed by a conditional instruction that wants to know a characteristic of the result such as those typically indicated by condition codes; however, the exception handler is not allowed by the architecture to update the condition code flags register of the architecture.
Therefore, what is needed is a microarchitecturally efficient means for the microinstructions of the microarchitecture instruction set to affect and examine condition code-like characteristics, without affecting the condition code flags of the architectural condition code flags register.

Microprocessor with microinstruction-specifiable non-architectural condition code flag register


A low pressure-high hydrogen flow rate process of cleaning a silicon wafer surface is described. The combination of process pressures below about 1 Torr with hydrogen flow rates up to about 3 SLM has been found to remove substantially all oxygen contamination from the silicon wafer surface at process temperatures less than about 800xc2x0 C. without the use of a reactive gas. After processing at such process pressures and flow rates, even lower levels of oxygen contamination may be achieved by then increasing the process pressure, the hydrogen flow rate, and the process temperature, though the process temperature still remains less than 800xc2x0 C. The combination of low pressure and high hydrogen flow rate can be achieved using a vacuum pumping speed of at least 30 cubic meters per hour. The present invention also describes an apparatus for cleaning a silicon wafer surface in which the processes of the present invention and other processes can be practiced.

The present invention relates generally to semiconductor processing and, more particularly, to a process and an apparatus for cleaning silicon surfaces.
The fabrication of semiconductor devices on a silicon wafer involves the formation of layers of various electronic materials, such as epitaxial silicon layers, passivation layers, insulation layers, etc., on a silicon surface. The performance of the semiconductor device depends upon the quality of the layers formed, which in turn depends strongly upon the cleanliness of the processing environment and of the underlying silicon surface.
Silicon surfaces are particularly susceptible to native oxide contamination. Native oxides are non-stoichiometric silicon oxides that can form any time a silicon surface is exposed to ambient atmosphere. Such exposure inevitably occurs during the course of device fabrication, for example, when wafers are being loaded into a processing chamber. Because the native oxides form under non-controlled atmospheric conditions, native oxides tend to grow at different rates from wafer to wafer, leading to different device performance depending on the wafer from which the device was formed. Moreover, the presence of native oxides may interfere with the electrical properties of the individual device, resulting in, for example, device noise, degraded performance, or even total failure.
To achieve acceptable semiconductor device yields per wafer and acceptable device performance, the silicon surface must be free of contaminants and impurities such as oxygen and carbon. One method of removing native oxides and other contaminants involves baking the wafer at a high-temperature, for example, greater than 1000xc2x0 C., immediately prior to the formation or deposition of a layer of electronic material. Typically, this involves baking the wafer in the same chamber in which the subsequent deposition step is performed. Such baking methods, however, generally cannot be used with wafers having devices thereon because most semiconductor devices cannot withstand such high temperatures.
To lower the baking temperature, some cleaning methods introduce a reactive gas, such as SiH4 or Si2H6, or GeH4, or NF3, into the chamber to help remove the native oxide layer and other contaminants. The use of such reactive gases allows the baking temperature to be reduced below 950xc2x0 C. However, such reactive gases not only attack the native oxide layer, but also other layers and devices on the wafer. The use of such reactive gases can leave residues in the chamber that can contaminate the wafers that are supposed to be cleaned. Some reactive gases also can attack the chamber walls. The chamber will thus require periodic cleaning and maintenance to remove the residues and repair any corrosion incurred during the wafer cleaning process.
One aspect of the present invention provides a process of cleaning a silicon surface. In one embodiment, the process involves transferring a silicon wafer into a chamber and maintaining the silicon wafer at a process temperature of not greater than about 800xc2x0 C. and a process pressure of less than about 1 Torr while flowing hydrogen gas across a surface of the silicon wafer.
In another aspect, the present invention provides an apparatus for cleaning a surface of a silicon wafer. In one embodiment, the apparatus includes a housing having therein a chamber defined by surfaces comprised of quartz. A reflector is positioned outside the chamber. A susceptor is positioned within the chamber and configured to accommodate the silicon wafer such that a first surface of the silicon wafer faces the reflector. A heater is configured to radiate heat towards only a second surface of the silicon wafer. An inlet port and a vacuum port are positioned opposite each other such that a gas introduced from the inlet port flows across the first surface of the silicon wafer towards the vacuum port.

Process and apparatus for cleaning a silicon surface


A cabinet For electronic components, the cabinet comprising an outer wall, a closure, and an attachment structure, the cuter wall encapsulating an internal space and forming an opening, the closure being attached to the outer wall by the attachment structure, and the attachment structure allowing movement of the closure relative to the outer wall between an open position where the opening is uncovered and a closed position where the opening is covered by the closure. To enable automatic and fast opening of the cabinet in case of over pressure, e.g. caused by arching of electronic components in the cabinet, the cabinet Further comprises a magnet structure comprising at least one magnet arranged to hold the closure in the closed position and to release the closure in response to a pressure in the internal space.

Cabinets for electric components such as for switchgear, converters, transformers and similar low or high voltage applications are made in different shapes and sizes, and to meet different requirements e.g. relative to corrosion resistance, the enclosure's ability to withstand prolonged exposure to humidity or chemical substances, and to the ability to withstand a rapid pressure increase or internal explosion, e.g. caused by arching in the cabinet. The cabinets are typically rated according to different standards and in accordance with the intended use.
Typically, the cabinets are prepared for arching by including in the cabinet, an arc-vent. Often, the arc-vent comprises a throttle or damper in a duct leading an excessive pressure out of the cabinet. Due to such arc--vents, even a rapid pressure increase or explosion may take place without destruction of the cabinet, and the potentially hot air is released in a controlled manner at a predetermined location.

Pressure relief arrangement with magnets


Embodiments for efficient queue management for cluster scheduling and managing task queues for tasks which are to be executed in a distributed computing environment. Both centralized and distributed scheduling is provided. Task queues may be bound by length-based bounding or delay-based bounding. Tasks may be prioritized and task queues may be dynamically reordered based on task priorities. Job completion times and cluster resource utilization may both be improved.

Data-parallel frameworks and scale-out commodity clusters are being increasingly used to store data, perform operations on and with data, and extract value from data. While some enterprises have large clusters, many others use public cloud providers. Such clusters run a wide variety of applications including batch data analytics jobs, machine learning jobs, and interactive queries. To reduce operational costs, and, therefore, improve return on investment, there is a trend toward consolidating diverse workloads onto shared clusters. However, doing so places considerable strain on a cluster scheduler, which has to deal with vastly varying and heterogeneous jobs, while maintaining high cluster utilization, fast and predictable job completion times, and offering expressive sharing policies among users.
Big Data clusters, consisting of several or even a large number of worker nodes, have a job scheduler and/or resource manager that determines how jobs (consisting of multiple tasks that can or may be executed in parallel on the worker nodes) get access to cluster resources.
Previous cluster schedulers such as Apache Hadoop YARN and Google's Borg have a logically centralized service, often called the resource manager (RM), which serves as a matchmaker between the resource needs of various jobs and the available resources on worker machines (nodes). Typically, machines exchange heartbeat messages with the RM once every few seconds, and are initiated either by worker machines (as in YARN) or by the RM (as in Borg). Through heartbeats, worker machines report resource availability to the RM, which in turn determines an allocation of tasks to machines and nodes in a cluster. This design has two main problems: first, the RM is in the critical path of all scheduling decisions; second, whenever a task finishes, resources can remain fallow between heartbeats. These aspects slow down job completion: a job with a handful of short tasks can take tens of seconds to finish. Worse, they can adversely affect cluster utilization especially when tasks are short-lived.
Table 1 shows an average cluster utilization (i.e., the percentage of occupied slots) with tasks of different durations for an 80-node YARN cluster. The label X-sec denotes a synthetic workload wherein every task lasts X seconds. The label Mixed-5-50 is an even mix of 5 sec. and 50 sec. tasks. Workload 1 is an actual production workload shown in FIG. 1. Notably, as task durations get shorter, cluster utilization drastically degrades, and can be as low or lower than 61%.
TABLE 1Average YARN cluster slot utilization for workloads withvarying task durations.5-sec.10-sec.50-sec.Mixed-5-50Workload 160.59%78.35%92.38%78.5483.38%
A few schedulers avoid logical centralization. Apollo, Sparrow, and others (as are known in the art) allow job managers to independently decide where to execute their tasks, either to improve scalability (in terms of cluster size or scheduling decisions rate) or to reduce allocation latency. The above problem with short-lived tasks becomes less prevalent, because tasks can be pushed onto queues at worker machines by each job manager. However, these schedulers are vulnerable to other problems including, inter alia:                (a) each job manager achieves a local optimum allocation, but coordination across various job managers to achieve globally optimal allocations is not possible;        (b) worse, the distributed schedulers do not always pick appropriate machines since they fail to account for the pending work in each queue;        (c) the assignments are vulnerable to head-of-line blocking when tasks have heterogeneous resource demands and durations.These aspects affect job completion times, leading to increased tail latency and unpredictability in job run times
To illustrate these aspects, FIG. 2 presents a cumulative distribution function (CDF) of job completion times for Workload 2 with YARN and an implementation of Sparrow's batch sampling on Mercury. It can be seen that the latter improves some very short jobs, but has a long tail of jobs that exhibit longer completion times. As will be shown later, this happens because batch sampling fails to make globally optimal task placement decisions, and because first-in-first-out (FIFO) queues at worker nodes suffer from head-of-line blocking.
In one naive attempt, an extended YARN that allows tasks to be queued at each node, thus masking task allocation delays, was demonstrated. In this case, an RM assigns tasks to node queues in a way that is similar to how it already assigns tasks to nodes. The resulting job completion times are depicted in the "YARN+Q" line of FIG. 2. As shown, naively offering FIFO queues at worker nodes in YARN can be worse than not having queues at all.

Efficient queue management for cluster scheduling