When an EGR control valve is fixed and a valve opening degree EGRVO of the EGR control valve is greater than a valve-opening threshold value EGRVOth, a limit value Qlim of the intake air amount is set to a prescribed amount Qlim1. Conversely when the EGR control valve is fixed and the valve opening degree EGRVO of the EGR control valve is less than or equal to the valve-opening threshold value EGRVOth, the limit value Qlim of the intake air amount is set to a prescribed amount Qlim2.

On internal combustion engines configured to recirculate exhaust gas, whose recirculation amount depends on an operating condition, back to the intake system, such internal combustion engines, which are configured to diagnose a failure in an EGR control valve disposed in an EGR passage for recirculating exhaust gas from the exhaust system to the intake system, are well known.
For instance, Patent document 1 discloses a technology in which a failure diagnosis for an EGR control valve, which is disposed in an EGR passage configured to connect an exhaust passage and an intake passage, is performed. As a result of the failure diagnosis, when it is determined that an open failure, in which the EGR control valve has been fixed in its open state, is occurring, fail-safe control is executed for limiting an output of the internal combustion engine.
In this Patent document 1, by virtue of execution of the above-mentioned fail-safe control, it is possible to avoid high output operation of the internal combustion engine when the EGR control valve has been fixed in the open state. Hence, there is a less tendency for the EGR control valve and the intake system to be excessively heated owing to high temperature EGR gas, and thus it is possible to prevent a secondary failure in the EGR control valve and a deterioration in performance of the internal combustion engine.
However, in the Patent document 1 there is a problem that it is impossible to prevent an engine stall, which may occur owing to a deterioration in combustion and/or a misfire caused by an excessive EGR (exhaust-gas-recirculation) rate resulting from the EGR control valve fixed or stuck in the open state.

Exhaust gas recirculation control device and exhaust gas recirculation control method for internal combustion engine


The proposal is for novel polymer dyestuffs obtained by condensing cationic biopolymers, e.g. chitosame, with dyestuffs which have a basic group, preferably a halogen function. The dyestuffs spread as a film on the fibers and can easily be washed out.

1. Field of the invention
This invention relates to polymeric dyes obtained by condensation of cationic biopolymers with dyes, to a process for their production, to formulations containing these dyes for dyeing fibers, to processes for dyeing fibers using the polymeric dyes and to their use for dyeing fibers.
2. Discussion of the Related Art
So-called substantive dyes or oxidation dyes are normally used for coloring keratin fibers, preferably human hair. Oxidation dyes consist of a primary intermediate and a secondary intermediate and are formed on the hair itself under the effect of oxidizing agents or atmospheric oxygen.
However, there is a need on the market for coloring products which enable the color of hair to be rapidly changed, i.e. which can be quickly and completely washed out. The hair normally has to be washed 5 to 6 times to remove known products, something which many consumers find unsatisfactory.
Another disadvantage of known hair coloring or hair tinting formulations is that the products always penetrate into the keratin fibers and, hence, cause damage--albeit normally slight--to the hair structure. Since the formulations do not act selectively on keratin fibers, the treated scalp is generally colored at the same time which consumers also find undesirable.
Accordingly, the problem addressed by the present invention was to provide new formulations for the temporary coloring of keratin fibers which would not have any of the disadvantages mentioned above.

Polymer dyestuffs and their use for dyeing fibres

Henkel Kommanditgesellschaft auf Aktien (KGaA)


An all dielectric self-supporting fiber optic communication cable for use between spaced-apart support towers of an electrical power transmission network. A central core including at least one optical fiber is surrounded by a layer of non-conductive stranded strength members that are wound about the core. The core includes a plurality of pliable buffer tubes, each of which houses a bundle of optical fibers. The buffer tubes are helically wound about a cylindrical element in order to provide temperature performance by preventing the buffer tubes from experiencing thermally induced movement when exposed to varying temperatures. Each of the stranded strength members comprises a bundle of non-conducting filaments or fibers that are formed about a reinforcing element and encapsulated by individual polyethylene jackets. The reinforcing element reduces the tendency of the filaments to compress as the extruded jacket cures. The stranded strength members are helically wound about the central core. An outer protective jacket is formed about the stranded strength members and encloses the entire cable. A faraday shield formed along the outer jacket brings the electric field to zero in the vicinity of the outer jacket, thus reducing or eliminating tracking currents along the surface of the outer jacket.

Electrical power utilities own or control rights of way for the transmission of bulk electrical energy over long distances. Typically, the utilities erect support towers or pylons for stringing 3-phase electrical conductors. These utilities have large investments in such rights of way and seek to optimize the return on these investments.
Utilities have in the past also erected communications cables in their rights of way for the purpose of maintaining communications between generating plants and other utility facilities. In the late 1970's and early 1980's, the utilities sought to utilize the high communication bandwidth of optical fiber communications technologies, which were just then becoming available.
Also in the 1980's, private long distance telephone carriers entered the market for long distance telephone communications, especially in the United States after the divestiture of AT&T, which separated the long distance carriers from the regional telephone operating companies. Electrical utilities have recently sought to take advantage of their rights of way by installing excess capacity in their communications cables and selling such capacity to regional telephone operating companies and private long distance telephone carriers as an additional source of revenue. Since optical fiber communications offer such significant bandwidths (e.g., a single optical fiber can carry over 10,000 simultaneous telephone conversations), utilities have sought efficient and effective means for installing fiber optic communication channels in their rights of way.
Any communication means provided in electrical utility rights of way must operate in the environment of strong electric and magnetic fields which emanate from the power transmission conductors. It is therefore problematic to use coaxial or other cables that include metal or other electrical conductors, because of noise and the inducement of electric currents. It is believed that optical fiber communications cables are preferable to any type of electrical communications cables because of higher communications capacity and immunity to interference.
Optical fibers for communications cables are usually provided in one of two configurations. In the first configuration, the optical fibers are contained within an electrically conductive cable installed as a ground wire, also called optical fiber overhead groundwire ("OPGW"). Examples of this approach are found in U.S. Pat. Nos. Re. 32,374 to Dey et al. and 4,944,570 to Oglesby et al. The ground wire is placed above the phase conductors in order to protect the system from electrical faults and from high current surges induced by a direct or near-by lightning strikes. Since OPGW cables are by definition electrical conductors, there is no concern about induced electrical currents in the conductors and the optical fibers are nonconductive and therefore immune to interference.
In a second configuration, the optical fibers are provided in a separate, self-supporting cable. This type of fiber optic cable does not take the place of a ground wire. Instead, the fiber optic cable is installed in self-supporting manner in addition to, and generally below, the phase and ground conductors and provides another way to add optical fiber communications capability to the rights-of-way of existing overhead electrical transmission and distribution systems. Typically, this self-supporting type of fiber optic cable would be placed below the ground wire in the vicinity of the phase conductors. Accordingly, it is important that such fiber optic cables be impervious or highly resistant to the induction of electrical currents because of the strong electrical fields from the power conductors.
Preferably, such non-OPGW cables are constructed of all-dielectric (i.e., non-conductive) materials in order to avoid problems associated with the strong electric fields. Using a nonconductive material also avoids problems such as excess heat resulting from current flowing through the cable, and the need to provide means for insulating or dissipating the unwanted induced current in order to prevent electrical shock to utility personnel and damage to equipment.
Various types of all dielectric or non-conducting self-supporting fiber optic cables are known in the art. Since optical fibers are fragile and prone to fail when subjected to too much tension, these cables typically utilize strength members comprising a non-conducting filament (such as DuPont's Kevlar.RTM. brand aramid fiber) or glass reinforced plastic to provide longitudinal strength for the cable. Prior to the present invention, the aramid or other plastic strength member has been stranded together or formed into a mesh and sealed within a plastic coating, cladding, or jacket. Examples of various approaches are demonstrated in U.S. Pat. Nos. 4,342,500, 4,776,665, 4,822,133, 4,838,635, 4,374,608, 4,892,382, and 5,016,973.
It is known that the cladding or jacket of such all-dielectric or non-conducting cables can be damaged or destroyed by various means. Abrasion may result from animals or during installation, and punctures can occur from projectiles (e.g., shotgun pellets) or other objects that come in contact with the jacket of the cable. In addition, the jacket of such cables can be damaged or destroyed by partial electrical discharge events that result from electrical currents induced on the cable jacket especially when wet, particularly in high-tension networks where the transmitted voltage exceeds 138 kV. These partial discharge events are known by those skilled in the art as "dry-band arcing" and are caused by moisture and other contaminants on the outer surface of the cable cladding. As a wet cable dries, it does not do so uniformly, and small dry areas may be formed about the circumference of the cable at various places. The electrical currents, also called "tracking currents", that are induced in the remaining wet portions of the cable surface may be great enough to support an arc across these dry bands. When this dry-band arcing occurs, heat and oxidation are generated that damage, and may eventually destroy, the cable jacket.
Eventually, the dry-band arcing or abrasion may result in the outer jacket of the cable being penetrated so that the interior portions of the cable are exposed to moisture and other contaminants. Once the integrity of the cable jacket is compromised and the woven or nonwoven filament type strength members are exposed to moisture, migration of the water throughout the cable is facilitated by the "wicking" action of the filaments themselves.
Once wicking has occurred, the cables are prone to sudden, catastrophic failure. Such failure generally results in one of two ways. In a first scenario, the volume of water entering the cable may eventually become so great that the cable collapses under its own weight. In a second scenario, the cable actually explodes as a result of the induced electrical current through the cable, which is now conductive because of water or moisture.
Penetration of the outer jacket is also undesirable because it may result in the strength members being exposed to ultraviolet light. It is known that prolonged exposure of Kevlar fibers to ultraviolet light results in the degradation of the strength properties of the Kevlar. Such degradation results in the weakening and potential failure of the cable.
Various cable designs have been developed to address the problems of dry band arcing and jacket penetration. Different types of jacketing constructions have been attempted in order to reduce the likelihood that the jacket will be penetrated as a result of abrasion. Examples of this approach may be found in the U.S. Patents cited above.
Other cable designs vary the composition of the cable in an effort to avoid damage resulting from dry-band arcing. Such changes include reducing the carbon content of the cable's outer jacket, and including additives that reduce the damage otherwise caused by the arching. A wide variety of materials will survive in the electric fields associated with power lines operating at or below 150 kV. Transmission systems operating in the range between 150 kV and 275 kV have been found to require special materials. At voltages above 275 kV, difficulties have been experienced developing a non-metal composition that will survive in the strong electric fields long enough to meet the needs of the electric power industry. An example of one attempt to control the dry-band arcing problem is found in U.S. Pat. No. 4,776,665 to Oestreich, where the cable itself is made slightly conductive in order to reduce the occurrence of dry-band arcing.
Other problems have been encountered in producing all dielectric self-supporting fiber optic cables. Those skilled in the art will appreciate that extruded jackets made of polyethylene or similar materials exhibit a tendency to shrink as they cure. When a cable's strength members include isolating jackets extruded about a bundle of flexible, non-conducting filaments or fibers, the shrinkage of the jacket along its longitudinal axis causes the filaments themselves to be compressed, likely due to friction between the extruded jacket and the filaments. As a result of the compression of the load bearing filaments, tension exerted upon the cable during installation will cause it to stretch until the filaments return to their original length and load is imparted to the filaments.
When a cable is first suspended between the towers employed in a power distribution system, the weight of the cable itself causes tension to be exerted upon the cable. Since the polyethylene jacket and other elements of the cable are unable to bear this initial load, the cable stretches until the compressed load bearing filaments return to their original length and tension is transmitted to the bundles of filaments. Two problems result from this initial elongation of the cable. The elongation leads to sagging of the cable and results in a reduction of the clearance between the ground and the cable. More importantly, however, the elongation causes tension to be transmitted to the optical fibers that are included in the cable's core. Those skilled in the art will appreciate that such tension eventually results in the attenuation of the amount of light passing through the optical fiber, or breakage of the optical fiber. In either case, the cable is no longer capable of effectively performing the task it was installed to do.
Despite prior art attempts to solve the problems associated with all-dielectric self supporting cables, prior self-supporting fiber optic cables are still susceptible to failure. Therefore, there is still a significant need for a non-conducting self-supporting fiber optic cable for use in conjunction with existing groundwires that demonstrates an improvement in prior art designs.

Field protected self-supporting fiber optic cable


A lightweight, high strength folding table having a top assembly which includes a novel high strength, plastic reinforcing core. Pivotally connected to the top assembly are supporting legs. Interconnecting the supporting legs with the top assembly are novel folding leg mechanisms which include top assembly engaging links and leg engaging links pivotally connected both to the top assembly engaging links and also to the supporting legs. A locking rod extends between the top assembly engaging links, the end portion of which is slidably received within a slot formed in each of the leg engaging links. When the rod resides within the locking portion of the slot, the top assembly engaging links and the leg engaging links are locked against relative pivotal movement. However, when the locking rod is lifted slightly, the rod ends move into the channel portion of the slot permitting free pivotal movement of the cooperating links.

1. Field of the Invention
The present invention relates generally to furniture. More particularly, the invention concerns an improved lightweight plastic folding table having a novel, structurally reinforced top and a unique folding leg mechanism.
2. Discussion of the Invention
Lightweight folding tables which exhibit superior structural characteristics and easy foldability are in wide demand for many industrial and institutional applications. Entities having great need for such tables include schools, convention centers, hotels, factories, business offices and various governmental entities. Particularly in demand are lightweight tables which are easily foldable for ready portable and storability when not in use.
While many types of lightweight tables been suggested in the past, a typical drawback of such tables is a lack of structural integrity which tends to contribute to limited useful life and to frequent structural failures. As a general rule, when the prior art furniture designers have attempted to correct the structural deficiencies in the prior art designs, the tables becomes excessively heavy and unduly bulky. As will be discussed in greater detail in the paragraphs that follow, the thrust of the present invention is to provide an improved lightweight, readily foldable table which embodies a unique structural reinforcement core that provide superior structural integrity to the furniture without unduly increasing its weight or bulkiness.
Exemplary of typical prior art plastic folding tables are those described in U.S. Pat. No. 4,951,576 issued to Cobos et al. The Cobos et al tables include upper and lower plastic table top halves and a framework grid, preferably made of wood, sandwiched therebetween. Another example of a prior art folding table is that described in U.S. Pat. No. 5,394,808 issued to Dutro et al. This table has a unitary table top formed of molded plastic preferably having an outer shell of non-cellular plastic with a filling of lightweight hardened foam. Other examples of prior art table constructions can be found in U.S. Pat. No. 5,271,338 issued to Bonham and in U.S. Pat. No. 3,628,470 issued to DeLucas. French Patent No. 1371706 issued to Evans shows a reinforcement member having a multiplicity of upstanding protuberances. However, the balance of the Evans structure is totally dissimilar to that of the present invention.
Because of the general similarities between the table of the present application and the table described in U.S. Pat. No. 5,694,865, which has been assigned to the assignee of the present inventors, is hereby incorporated by reference as though fully set forth herein.


An umbrella includes a hollow tubular handle extending in an axial direction, the handle having an upper edge and a lower portion; an elongated rod having an upper end and a lower end, the elongated rod movable in the axial direction within the hollow tubular handle; a plurality of struts pivotally mounted to the upper end of the elongated rod for movement in a range between a storage position substantially parallel to the axial direction and adjacent to the elongated rod, and an open position substantially perpendicular to the axial direction; a web of flexible, water-resistant material connected to the struts; and a locking mechanism connected to a lower end of the elongated rod for engaging with a lower portion of the tubular handle to releasably lock the struts in either the open position in which the struts rest on the upper edge of the tubular handle, and the closed position in which the struts are positioned within the tubular handle, the locking mechanism including two diametrically opposite spring fingers mounted to the lower end of the elongated rod, each spring finger having a first step for engaging with the lower portion of the tubular handle to releasably lock the struts in the open position, and a second step for engaging with the lower portion of the tubular handle to releasably lock the struts in the closed position, the first outer step being positioned below and radially outward of the second outer step on each spring finger.

The present invention relates generally to umbrellas, and more particularly, is directed to an emergency umbrella in which the handle also functions as a carrying case.
Because of unpredictability in the weather, it would be desirable to always have an umbrella ready at hand in case of an emergency. However, the size and bulkiness of conventional umbrellas does not make this feasible. Although there are presently on the market conventional umbrellas sold, for example, under the trademark "Totes" which are compact and fit within a briefcase, such umbrellas are rather complex in construction, use costly raw materials and are therefore expensive and relatively heavy.
Disposable umbrellas of the type in which the handle also functions as a carrying case are disclosed, for example, in U.S. Pat. Nos. 4,624,275; 4,842,003; and 4,966,179, all having at least one common inventor herewith, and the entire disclosures of which are incorporated herein by reference.
With the disposable umbrella of U.S. Pat. No. 4,624,275, the canopy and struts must be physically removed through one end of the tubular handle and then attached at the opposite end thereof. This may be rather inconvenient and troublesome.
With U.S. Pat. Nos. 4,624,275 and 4,842,003, the struts are stored in the handle in an inverted configuration. Accordingly, it is difficult to provide a pre-bowed canopy for use therewith.
U.S. Pat. No. 2,700,390 discloses a disposable umbrella in which the handle is detachable from the main portion of the umbrella and serves as a carrying case therefor. With this umbrella, the struts or ribs are normally pivoted in a direction opposite that from a normally closing umbrella, that is, in a direction inverted from a conventional umbrella. In order to prevent the struts from inverting during normal use, it is necessary with such an umbrella to utilize cords or similar type elements to tie down the struts. Further, when the umbrella is contained within the handle, the struts and canopy are inverted first and then inserted into the handle, with the hub being used as a cap on top of the open end of the handle. In operation, the entire canopy, struts and cap must first be removed from the handle, then inverted so that the cap is used as a plug on top of the handle. The canopy and struts must then be pushed down to their operable position, with the struts then being tied down by cords.
U.S. Pat. No. 3,186,421 discloses a compact umbrella in which an insert block is slidably movable within a handle between a first stored position and a second open position, with the struts pivotally connected to the insert block. When the insert block is moved to the open position, the struts are opened by gravity and position themselves within respective receiving slots in the handle. It is the receiving slots that maintain the struts in their open position.
U.S. Pat. No. 4,084,600 discloses an umbrella in which the struts or ribs are pivotally secured to a hub which slides within the handle. In this patent, the struts or ribs are pivotally attached to the hub for movement to a completely inverted position when it is carried within the handle. However, a relatively complicated arrangement of a biased locking plate which biases the inner ends of the struts to maintain them in their open position is provided. U.S. Pat. No. 2,439,752 also discloses an umbrella in which the struts and canopy are insertable within a handle. The struts and canopy are locked in place at the upper end of the handle by a coupling or fastening pin which passes through openings an opposite sides of the upper part of the tubular handle. However, to close the umbrella, the ribs are not pivotable downwardly into the handle, but only laterally in the plane of the umbrella in its open position and then removed from the handle and inserted therein for storage.
U.S. Pat. No. 4,456,023 discloses an umbrella which is storable within its carrying handle. However, there is no disclosure as to how the umbrella is opened and from the disclosure in the patent, it appears that such an umbrella has a relatively complicated linkage assembly similar to that of compact umbrellas sold under the trademark "Totes".
U.S. Pat. No. 892,813 discloses a folding umbrella in which the struts fit within the handle during storage, and the handle functions to hold the umbrella when the umbrella is in its open configuration. However, the shaft to which the struts are mounted functions as an extension of the umbrella in its opened configuration, and accordingly, the struts are provided with a pivot point midway therealong for storing the struts in the handle.
U.S. Pat. No. 2,747,592 discloses a collapsible umbrella which is also relatively complicated in construction and use.
French Pat. No. 1,429,394 discloses an umbrella having a ball which is slidable within a handle between the upper and lower positions. A canopy is secured by angled cords to the ball and is normally held with the ball in the handle. In use, when the ball is pulled out by an auxiliary cord, the canopy is forced out of the handle and is held in its open position by the angled cords secured to the central ball. In effect, the French patent is similar to the aforementioned U.S. Pat. No. 2,700,390 which requires cords to tie down the struts or canopy to prevent the umbrella from inverting. Although U.S. Pat. No. 2,994,333 discloses a peripheral cord, this cord is used for securing the canopy, and separate tie down cords are required for imparting a bow shape to the umbrella.
U.S. Pat. No. 3,709,238 discloses an umbrella in which the hub which contains the umbrella struts connected thereto is slidable within the handle. During folding of the umbrella, the hub slides inwardly into the handle, and the struts and canopy fold upwardly and follow the hub into the handle. An inwardly extending annular shoulder is provided for preventing escape of the hub from the handle. Radially extending flexible stays or struts support the canopy material in the extended open position. However, to maintain the canopy in its open position, extending cord members are connected between the struts and the hub and are, therefore, similar to the aforementioned U.S. Pat. No. 2,700,390 and French Pat. No. 1,429,394.
U.S. Pat. No. 284,495 discloses an umbrella having a canopy provided with a cord enclosed in the canopy seams, and a strut or rib structure incorporating a slit tubular recess into which the cord is fit to lock the canopy in place. Such recessed strut is inherently of uniform cross section, determined by the size and shape of the, cord.
U.S. Pat. No. 369,374 discloses a cane umbrella. As described therein, struts are tapered so that the peripheral end will have considerably more flexibility and the struts or ribs can be of solid cross-section or hollow on the underside. The struts or ribs are hingedly connected to a central hub which is locked down on top of the handle by a screw-threaded center piece. However, to store the umbrella, the center piece must be unscrewed and the hub removed, whereupon the struts are pivoted to a closed position and then inserted through the handle, followed by closure of the center piece on top of the handle. This renders the construction relatively complicated in use.
U.S. Pat. No. 3,844,301 discloses a collapsible umbrella in which the struts are fixedly held to a hub which is slidable within the handle of the umbrella. With this construction, guide tracks must be employed in the handle to deploy the struts in an arcuate configuration as they exit the handle. Because of the guide tracks that must be employed within the handle, the upper end of the handle is made with an outwardly flared configuration. Without the guide tracks in the handle, there would be no initial bending of the struts as they exit the handle. In addition, this patent discloses struts of a uniform cross section. In this regard, because of such uniform cross section, the struts must have a uniform bending throughout the length thereof. More importantly, it is necessary to..use struts of a uniform cross-section in view of the use of guide tracks in the handle. If the struts were of varying cross section, the guide tracks would be inoperative or at least would function improperly.


The present invention provides for analyzing document content for display with reduced cognitive load, and assists those who are blind, have low vision, or have cognitive problems. This present invention also aids those who prefer to receive condensed information orally. Document content is analyzed, a set of salient words and phrases are generated from the document content, the salient words and phrases are tagged, and the set of salient words and phrases are read.

When reading newspapers, documents, or web pages, there are significant amounts of text in which salient information is imbedded. For people with low vision, dyslexia, blindness, some eye-motor disabilities, and most cognitive deficiencies, text density and organization create challenges. Not only is there a huge cognitive processing demand required, but the individual must parse meaningful information from non-meaningful information without the benefit of additional cueing (e.g., color, chunking, etc). In addition, the blind person using a screen reading device must perform this higher level cognitive function while also listening to the information, making it necessary to retain large quantities of spoken information in working memory buffers to derive the meaning contained within a few key words.
Typical industry solutions to date utilize a document summarizer. Summarization technology addresses the problem of information overload by reducing a full document to a surrogate summary consisting of a few sentences extracted from the document in a way which retains the essence of the document content. Summarization technology addresses technical challenges like coherence, cohesion, and information quotient. However, even though the information reduction it achieves would help a person with cognitive disabilities, summarization does not explicitly address perceptual problems which might require solutions identifying salient text fragments of granularity smaller than a sentence.
In particular, none of the summarization technologies listed above 'tag' words or phrases with a salience measure. Consequently, these technologies are unable to focus on short text fragments; brevity being of the essence from the point of view of a person with cognitive disabilities. Furthermore, not much attention has been paid to contextualizing the salient fragments. Summarization solutions do not, typically, relate a summary to the original document source, which makes it hard to create a cognitive map between the summary and the full text.
Therefore, there is a need for a solution to reduce the heavy cognitive load, addressing at least some of the problems associated with conventional document summarizers.

Document content analysis technology for reducing cognitive load

International Business Machines Corporation


The present disclosure includes purification and deposition methods for single-walled carbon nanotubes (SWNTs) that allow for purification without damaging the SWNTs. The present disclosure includes methods for reducing electrical resistance in SWNT networks.

Single-walled carbon nanotubes (SWNTs) have attracted attention because of their unique electronic and mechanical properties. They have the highest measured tensile strength, are flexible, lightweight, and exhibit low power consumption while retaining high on/off ratios in electronic materials. These seamless tubes of graphene are typically micrometers long and one nanometer in diameter. However, unlike graphene, SWNTs exist as either semi-conductive or metallic conductors due to quantum confinement effects resulting from their curvature. Therefore, there is particular interest in using SWNTs for electronic applications.
Despite their great potential, the widespread use of SWNTs in electronic materials remains stalled by issues with unbundling and purifying them in order to obtain much greater precision over their electronic properties. This is important because, regardless of the growth method, as-produced (AP) grade SWNT soot is a mixture of SWNTs, metal catalyst nanoparticles, and amorphous carbon. The majority of existing purification methods involve oxidizing SWNT soot in strong acids and/or gases. These types of treatments remove metal catalyst nanoparticles and amorphous carbon, but significantly damage the SWNTs and increase their electrical resistance. In addition, use of SWNTs in electronic materials will require addressing a major barrier—the reduction of their high sheet resistance (R).

Bulk purification and deposition methods for selective enrichment in high aspect ratio single-walled carbon nanotubes

UNIVERSITY OF GEORGIA RESEARCH FOUNDATION, INC.


The present invention relates to digital-to-analog conversion. In particular, it has application to conversion of pulse code modulated signals, such as used in CDs and DVDs, to a pulse width modulated or analog signal.

The present invention relates to digital-to-analog conversion. In particular, it has application to conversion of pulse code modulated signals, such as used in CDs and DVDs, to a pulse width modulated or analog signal.
Many streaming media formats produce a multibit data stream. For instance, audio CDs typically encode music as a 16-bit or 24-bit pulse code modulated signal. MP3 files also may be decoded as pulse code modulated signals.
Audio fidelity depends in part on the signal to noise ratio (SNR) of the digital-to-analog (D/A) converter used. This converter may be part of a CD player, located on a sound card or included with powered speakers that are digitally driven. Manufacturers compete on the basis of the SNR achieved by their equipment. For instance, Creative Labs currently (in September 2005) advertises the Audigy Pro 4 sound card as achieving an SNR of 113 decibels in some modes.
Accordingly, an opportunity arises for new digital designs, especially digital designs that achieve strong signal-to-noise ratios.

Low noise digital to signal interval converter with audio applications


A releasable locking device has a housing and an elongated member extending from the housing. The elongated member has an opening extending therethrough. A shaft extends through the opening of the elongated member. An actuator member extends from an end of the shaft and is positioned within an opening of the housing. A biasing member is positioned between the actuator member and a wall of the housing and is completely within an opening of the housing and not in the elongated member.

This invention relates to release pins. Releasable securing devices, such as ball pins, are commonly used for joining the parts of industrial fixtures releasably together. Such ball pins have a hollow, hardened stem inserted through mating bores in the parts to be joined, the stem terminating in an abutment surface to be pressed against the top side of the parts; and depressible or retractable ball detents near the tip of the pin, to engage the parts on their bottom side.
Quick connect ball locking devices generally include a plurality of detents, such as balls, trapped within a tube but protruding out openings therein. A ball actuator is reciprocal within the tube and movable from a first position wherein the balls are retracted substantially within the tube or moved outwardly a sufficient distance to lock the balls within a mating receptacle. An example of such a ball locking device is shown in U.S. Pat. No. 5,394,594 which is incorporated by reference herein.
Referring in particular to FIG. 1, in previous fastener devices, a compression spring 1 is mounted within an enlarged bore 2 at one end of the pin shank 3 and this spring normally holds a shoulder 4 on the spindle 6 against an abutment 5 on the pin shank. In this position of the parts the land 6 hold the balls 8 in a projected position. An actuator button 9 on the shank may be moved manually to bring a groove 11 into registry with the balls and thereby permit inward movement of the balls to a release position.
A problem with these existing release pins is that the springs are captured within a bore of the pin shank and are not easily accessible from outside of the release pin. Thus it is difficult to change the size of the spring without also changing the cavity size of the pin. A spring being positioned outside of the cavity allows the release pin to be easily reloaded, and also increases the strength of the release pin.
Furthermore, existing release pin designs do not have holes or slots for receiving ropes or lanyards to keep the pin attached to the device it is being used with, or to a wall or other support surface. Thus, there is a need for providing holes on the release pin for lanyards so that when the pin is pulled out of engagement, it stays attached by the lanyard connection.
Thus, it is desirable to develop a new and improved release pin which has an easily replaceable spring which overcomes the above-mentioned deficiencies and others and produces advantageous overall results.


A testing system for a power supply (40) includes a testing chamber (10), a control switch, an electrical load (50), an AC source (60), and a PLC (30). The power supply has a voltage choice switch. The testing chamber receives the power supply therein. The testing chamber provides a first or a second ambient temperature and supplies a testing environment for the power supply. The control switch switches the power supply to operate between a standby state and an operational state. The electrical load is connected to the power supply. The AC source is connected to the power supply. The AC source outputs the first voltage or the second voltage to the power supply. The PLC controls switching states of the voltage choice switch and the control switch in a manner such that the power supply selectively operates in one of combined switching states of the voltage choice switch and the control switch.

1. Field of the Invention
The present invention relates to testing systems, and more particularly to a temperature testing system for a power supply.
2. Description of Related Art
A power supply is very important in a computer for supplying power to each part of the computer and ensuring normal running of the parts in the computer. If the power supply does not function properly, the computer will not run normally. Therefore, the working parameters of the power supply need to be tested during design, manufacture, and testing of the computer.
In a temperature testing system for a power supply, it is common to test under a variety of conditions to ensure ability of the power supply to operate properly in different working states. It usually takes twelve hours to test a power supply in the temperature testing system, and testing conditions need to be manually changed every two hours. This process is very complex for the testing operators, and adds to the time and cost of testing.
What is needed, therefore, is a temperature testing system for a power supply with the testing conditions being changed automatically.

Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd.


A method of forming a semiconductor device, including providing a substrate having a first insulative layer on a surface of the substrate, and a device layer on a surface of the first insulative layer, forming a spacer around the first insulative layer and the device layer, removing a portion of the substrate adjacent to the first insulative layer in a first region and a non-adjacent second region of the substrate, such that an opening is formed in the first and second regions of the substrate, leaving the substrate adjacent to the first insulative layer in a third region of the substrate, filling the opening within the first and second regions of the substrate, planarizing a surface of the device, and forming a device within the device layer, such that diffusion regions of the device are formed within the device layer above the first and second regions of the substrate, and a channel region of the device is formed above the third region of the substrate.

1. Technical Field
The present invention relates generally to semiconductor devices, and more particularly, to a method of forming a silicon-on-insulator (SOI) device having a buried oxide (BOX) layer, and the structure so formed.
2. Related Art
Conventionally silicon-on-insulator (SOI) devices are formed having a buried oxide layer (BOX) under the active regions of a field effect transistor (e.g., a MOSFET device). The BOX layer, which is conventionally made uniformly thin under the active area of the device, produces a faster MOSFET device for several reasons. First, the BOX layer reduces the capacitance between the source/drain regions and the substrate of the device. Second, the channel region, between the source/drain regions, becomes decoupled from the substrate allowing movement, or "floating" of the channel region potential with respect to the substrate. For example, when the channel region potential floats positive, the threshold voltage drops, thereby increasing the drive current.
One of the difficulties typically encountered with this type of device, however, is determining the optimal BOX layer thickness. The capacitance between the source/drain region and the substrate increases as the thickness of the BOX layer is decreased, increasing the circuit loading. The amount of channel region potential "floating" also increases with increasing thickness of the BOX layer due to the reduced capacitance coupling to the substrate. Unfortunately, a floating channel region has the undesirable effect of producing a fluctuating threshold voltage, and therefore, an unpredictable device.
Therefore, there is a need in the industry for a method of forming a semiconductor device that addresses these and other problems.

Structure and method for thin box SOI device


The present invention relates to the discovery of novel genes encoding Lipid Metabolic Pathway (LMP) polypeptides. Therapeutics, diagnostics and screening assays based on these molecules are also disclosed.

The risk of developing atherosclerosis, the leading cause of death in Western industrialized countries, is directly related to plasma concentrations of low density lipoprotein (LDL) cholesterol and inversely related to concentrations of high density lipoprotein (HDL) cholesterol (J. L. Breslow, in The Metabolic and Molecular Bases of Inherited Disease, C. R. Scriver, A. L. Beaudet, W. Sly, D. Valle, Eds. (McGraw-Hill, New York, 1995), pp 2031-2052; and S. M. Grundy, (1995) J. Am. Med. Assoc. 256: 2849).
The first observable event in the formation of an atherosclerotic plaque occurs when blood-borne monocytes adhere to the vascular endothelial layer and transmigrate through to the sub-endothelial space. In vitro data suggests that adjacent endothelial cells at the same time produce oxidized low density lipoprotein (LDL), which are taken up in large amounts by the monocytes through scavenger receptors expressed on their surfaces.
These lipid-filled monocytes are called foam cells, and are the major constituent of the fatty streak, which is characteristic of an atherosclerotic lesion. Interactions between foam cells and the endothelial and smooth muscle cells which surround them lead to a state of chronic local inflammation which can eventually lead to smooth muscle cell proliferation and migration, and the formation of a fibrous plaque. Such plaques occlude the blood vessel concerned and thus restrict the flow of blood, resulting in ischemia, a condition characterized by a lack of oxygen supply in tissues of organs due to inadequate perfusion.
Although normal and pathologic LDL metabolism is well-defined (J. L. Goldstein, H. H. Hobbs, M. S. Brown in The Metabolic and Molecular Bases of Inherited Disease, C. R. Scriver, A. L. Beaudet, W. Sly, D. Valle, Eds. (McGraw-Hill, New York, 1995), pp 1981-2030), HDL metabolism is relatively poorly understood (J. L. Breslow, in The Metabolic and Molecular Bases of Inherited Disease, C. R. Scriver, A. L. Beaudet, W. Sly, D. Valle, Eds. (McGraw-Hill, New York, 1995), pp 2031-2052; S. M. Grundy, (1995) J Am. Med. Assoc. 256: 2849; G. Assman, A. von Eckardstein, H. B. Brewer Jr. in The Metabolic and Molecular Bases of Inherited Disease, C. R. Scriver, A. L. Beaudet, W. Sly, D. Valle, Eds. (McGraw-Hill, New York, 1995), pp 2053-2072; W. J. Johnson et al., (1991) Biochim. Biophys. Acta 1085:273; M. N. Pieters et al., (1994) Ibid 1225:125; and C. J. Fielding and P. E. Fielding, (1995) J Lipid Res 36:211).
HDL delivers cholesteryl ester to nonplacental steroidogenic tissues (ovary, adrenal glands, and testis) for hormone synthesis (J. M. Anderson and J. M. Dietschy (1981) J. Biol. Chem. 256: 7362; M. S. Brown et al., (1979) Recent Prog Horm. Res. 35:215; J. T. Gwynne and J. F. Strauss III, (1982) Endocr. Rev. 3:299; B. D. Murphy et al., (1985) Endocrinology 116: 1587) and transports cholesterol from extrahepatic tissues to the liver (reverse cholesterol transport) e.g. for incorporation into bile (J. L. Breslow, in The Metabolic and Molecular Bases of Inherited Disease, C. R. Scriver, A. L. Beaudet, W. Sly, D. Valle, Eds. (McGraw-Hill, New York, 1995), pp 2031-2052; S. M. Grundy, (1995) J. Am. Med. Assoc. 256: 2849; G. Assman, A. von Eckardstein, H. B. Brewer Jr. in The Metabolic and Molecular Bases of Inherited Disease, C. R. Scriver, A. L. Beaudet, W. Sly, D. Valle, Eds. (McGraw-Hill, New York, 1995), pp 2053-2072; W. J. Johnson et al., (1991) Biochim. Biophys. Acta 1085:273; M. N. Pieters et al., (1994) Ibid 1225:125; and C. J. Fielding and P. E. Fielding, (1995) J. Lipid Res 36.211).
Unlike LDL, wherein the protein component (apoB) is lysosomally degraded after endocytosis via the LDL receptor (J. L. Goldstein, H. H. Hobbs, M. S. Brown in The Metabolic and Molecular Bases of Inherited Disease, C. R. Scriver, A. L. Beaudet, W. Sly, D. Valle, Eds. (McGraw-Hill, New York, 1995), pp 1981-2030), HDL is delivered via "selective lipid uptake" in which the protein component (apoA) is not degraded (R. Wishart and M. MacKinnon (1990) Biochim. Biophys. Acta 1044:375).
The class B scavenger receptor, SR-BI, has been shown to bind HDL cholesterol and mediate uptake into tissue (Acton, S. et al., Science 271:518-520). In this lipid uptake pathway, HDL docks to SR-BI, delivers cholesterol esters and possibly other lipids to the cell, and then dissociates from SR-BI and resumes circulating in plasma. Excess LDL was not found to inhibit HDL association with SR-BI, suggesting that nLDL in vivo does not significantly interfere with HDL binding to SR-BI.
SR-BI has also been shown to bind with high affinity to modified proteins (e.g. acetylated LDL, oxidized LDL, maleylated bovine serum albumin) and native LDL (Acton, et al., (1994) J. Biochem 269:21003-21009). SR-BI and CD36, another class B scavenger receptor, have also been shown to bind anionic phospholipids, such as phosphatidylserine and phosphatidyl inositol, but not zwitterionic phospholipids, such as phosphatidylcholine, phosphatidylethanolamine and sphingomyelin. Competition studies suggest that anionic phospholipids bind to SR-BI at a site close to or identical with the sites of native and modified LDL binding and that the interaction may involve polyvalent binding via multiple anionic phospholipid molecules (Rigotti, A , S. Acton and M. Krieger (1995 J. Biochem 270:16221-16224).
SR-BI is expressed in a variety of cells and tissues including macrophages, endothelial cells, fat, lung, liver, adrenal gland and steroidogenic tissue.
Molecules involved upstream (e.g. activators or repressors) and/or downstream (whether positively or negatively regulated) of the SR-BI receptor in a lipid metabolic pathway would be useful in the prevention, treatment and diagnosis of diseases and conditions caused by abnormal or inappropriate lipid metabolism and/or transport, such as atherosclerosis and biliary tract disorders (e.g. gall stone formation).

Method of making lipid metabolic pathway compositions


Integrated circuits can include an integrated capacitor with a metal alloy layer. Methods for forming such integrated circuits can include providing a substrate, forming a first electrode including depositing a metal alloy layer having a first surface and an exposed second surface, etching the exposed second surface of the metal alloy layer thereby increasing the surface roughness of the second surface of the metal alloy layer, forming a capacitor dielectric on the first electrode and forming a second electrode on the capacitor dielectric. By providing a metal alloy layer and etching the second surface of the metal alloy layer, an increased capacitance of the integrated capacitor is achieved.

Integrated circuits like memory circuits comprise memory cells in which digital information are stored. DRAMs (Dynamic Random Access Memories) comprise memory cells in which the information is stored by electrical charges accumulated in a capacitor. A capacitor of a memory cell is usually formed as a stacked capacitor or as a deep trench capacitor. A deep trench capacitor is formed by etching a deep trench into a substrate, forming a first electrode in a substrate region surrounding the sidewalls and the bottom of the deep trench, by depositing a capacitor dielectric on the bottom and on the sidewalls of the trench and by filling the trench with a conductive material thereby forming the second electrode. The second electrode is connected to a source/drain-region of a transistor. Another source/drain-region of the transistor is connected to the bitline. The gate electrode of the transistor is connected to the wordline.
Due to the shrinking dimensions of memory cells of future generations of memory products, it becomes increasingly difficult to store a sufficiently large amount of electrical charges in the memory cell. If a storage capacitor is formed as a deep trench capacitor, reducing memory cell dimensions requires decreasing the lateral cross-section of the deep trench capacitor. The maximum depth of a deep trench capacitor cannot be increased without narrowing the process window of the process technology. Accordingly, the capacitance of an integrated capacitor decreases with shrinking memory cell dimensions unless appropriate measures are taken to enlarge the capacitance per capacitor plate surface of the integrated capacitor. A sufficiently high total capacitance of an integrated capacitor is required for preserving a sufficiently large amount of charges during the refresh time in order to allow safe reading of the stored digital information.
It is known that a sacrificial undoped layer of hemispherical grain silicon (HSG) can be provided as a mask over polysilicon. The polysilicon layer is etched using the HSG-silicon layer as an etching mask. The HSG-silicon layer is then removed from the polysilicon layer. It is also known to form mesopores in a substrate by annealing the substrate in a furnace in an atmosphere containing oxygen.
Another approach used for deep trench capacitors is widening a lower trench portion. The surface of the capacitor plates is increased. Trench-widening is called "bottling" and is performed by wet etching of a lower trench portion below an upper trench portion where an isolation collar is to be formed later. During wet etching, an upper trench portion is protected by a protecting layer in order to preserve lateral trench dimensions in the upper trench portion close to the substrate surface.
Widening the cross-section of a lower trench portion, however, increases the risk of short-circuits between deep trench capacitors of adjacent memory cells. Furthermore, this technique is only applicable to deep trench capacitors but not to stacked capacitors.
Though the hemispherical grain technique increases the capacitance of deep trench capacitors and stacked capacitors to some extent, techniques for further increasing the capacitance are required.

Method for forming a capacitor for an integrated circuit and integrated circuit


A hard disk drive including a flexible printed circuit (FPC) in which a base layer and a cover layer are arranged with a circuit layer therebetween. In addition, a damping material is coupled at a predetermined portion of the signal patterns in the circuit layer so as to cross the signal patterns. The hard disk drive reduces vibration energy over an entire frequency band to minimize the effect of vibration on servo control and improve the performance of the hard disk drive.

1. Field of the Invention
The present invention relates to a flexible printed circuit (FPC), and more particularly, to an FPC to minimize vibration energy of noise.
2. Description of the Related Art
A hard disk drive is an auxiliary memory device of a computer to write and read information on a magnetic disk by using a magnetic head operating as an electromagnet.
FIG. 1 illustrates the structure of a conventional hard disk drive 20. Referring to FIG. 1, the conventional hard disk drive comprises: a disk 13 to store information; a spindle motor 15 to rotate the disk 13; an actuator 23 having a magnetic head 25 to write and reproduce information on and from the disk 13; a voice coil motor 21 to drive the actuator 23; a flexible printed circuit (FPC) 11 to transfer electrical signals from a printed circuit board (PCB) (not shown) to the actuator 23; and a bracket 31 to support the FPC 11.
The disk 13 is formed of a parking zone micro-processed by a laser at an inner region of the disk 13 and a data zone at the outer circumference of the parking zone, on which magnetic signals are written. In this case, the parking zone is coupled with the spindle motor 15 to mount the magnetic head 25 in a power-off state. Servo signals to report the location of information to be written are pre-written on tens of thousands of tracks along the circular shape of the disk 13.
The actuator 23 includes a fantail unit 19 having the voice coil motor 21 to drive the actuator 23; a pivot bearing 17 at the center of rotation of the actuator 23; and the magnetic head 25 having a write head to write data on the disk 13 and a read head to reproduce information from the disk 13.
The PCB transfers electrical signals to the FPC 11 and the FPC 11 transfers the electrical signals to the actuator 23. The electrical signals are transferred from the actuator 23 to the voice coil motor 21. The actuator 23 is rotated centering upon the pivot bearing 17 by electromagnetic force from interaction between current and magnets in the voice coil motor 21. Accordingly, the actuator 23 moves from the parking zone to the data zone.
FIG. 2 illustrates the structure of the conventional FPC 11. Referring to FIG. 2, head signal patterns RDX; Read Data X, RDY; Read Data Y, WDX; Write Data X, and WDY; Write Data Y to transfer and/or receive the electrical signals to and from the magnetic head through a pre-amplifier (not shown), voltages VDD; positive DC supply and VSS; negative DC supply to supply voltage to the pre-amplifier, a ground GND to ground, and a current pattern VC; Voice coil to apply the current to the voice coil motor 21 are arranged on the conventional FPC 11.
In the case of writing and/or reading data on the hard disk drive 20, the magnetic head 25 moves along the tracks of the disk 13 to write and/or read data. It is most preferable that the rotating track of the disk 13 forms an exact circle, and the magnetic head 25 precisely writes and reads data. However, in reality, the disk 13 rotates in a distorted circle caused by vibration of the spindle motor 15. Accordingly, a runout occurs, in which there is a difference between the locations of the track and the magnetic head.
Two kinds of runout include repeatable runout (RRO), which repeats every rotation and non-repeatable runout (NRRO), which does not repeat every rotation.
The RRO means the rotation of the disk 13 to form a waveform with a specific period caused by the assembly deflection of the disk 13 or the vibration of the hard disk drive 20. Since the waveform is repeated periodically, differences in location between the track and the magnetic head 25 can be compensated for by recording waveform information in a servo memory.
In order to compensate for the RRO and test reliability, a burn-in test is performed during the manufacturing process of the hard disk drive by varying conditions such as temperature and voltage. However, it is difficult to completely compensate for the RRO because various factors like FPC bias, windage bias, and heat complicatedly operate in the manufacturing process. The FPC bias means the force applied from the FPC to a head stack assembly (HSA) mechanically. The windage bias means the force applied to the HSA according to the effect from rotating fluctuation of the disk to the FPC.
In the FPC 11, since the head signal patterns RDX, RDY, WDX, and WDY are physically close to the current pattern VC and the voltage patterns VDD and VSS, through which a relatively large current flows, noise affects the head signal patterns RDX, RDY, WDX, and WDY. In addition, a low frequency of about 340 Hz caused by the natural frequency of the FPC 11 affects servo control.
In particular, since the write head signal patterns WDX and WDY are nearer to the voltage patterns VDD and VSS and the current pattern VC than the read head signal patterns RDX and RDY, the effects are much more serious in a write mode than in a read mode.
Consequently, since the compensation values for the RRO vary according to the operating environment and the kind of hard disk drive, the performance of hard disk drives is affected by disturbances like NRRO and low frequencies of under 1 kHz, which are not servo control frequencies of the FPC. NRRO indicates the rotation of the disk to form a distorted waveform without a specific period.
Referring to FIG. 3, a frequency response graph of the conventional FPC illustrates current strength peaks at around 340 Hz and 750 Hz. Moreover, the peaks are repeated at radio frequencies above 1 kHz. Since the natural frequencies of the conventional FPC are located at the frequency bands 340 Hz and 750 Hz, resonance occurs between the natural frequencies of the FPC and noise. Consequently, the vibration energy at the frequency bands is relatively strong, thereby generating the peaks.
As described above, in a conventional hard disk drive, seek time, which means the time to seek a track, and position error signal (PES) are increased by the noise effect from the current pattern VC and the voltage patterns VDD and VSS, by the difference between compensation values of the RRO, and by the effect from the low frequency noise. As a result, the performance and yield rate of the conventional hard disk drive is deteriorated.

Hard disk drive comprising flexible printed circuit with damping material


A method and apparatus for determining a set of functional parameters using a fluoroscopic radiography apparatus of the type comprising an X-ray source, a detector or recorder of the radiation facing the source, the source and the detector or recorder being installed on a mobile support capable of movement with respect to a table placed between the source and the detector or recorder on which a patient with a region of interest to be X-rayed will be placed. The method comprises a) movement of the support following a given movement with respect to the table, repeated during a given time; b) acquisition by the detector or recorder of a series of images of the region of interest during movement of the support with respect to the table; c) reconstitution of a series of three-dimensional models of the region of interest, starting from a series of acquired images; and d) determination of all functional parameters.

The invention relates to improvements to a radiographic imaging process and apparatus for the process. In particular, an embodiment of the invention and equivalents is an apparatus for fluoroscopic imaging and a method for monitoring the evolution of an action procedure in an angiography operating theater.
Vascular or angiography operating theaters are increasingly used for therapeutic applications. Some of these require anatomic information about vascular pathologies encountered and to be treated, and also functional information, particularly in the operational neuroradiology domain. These applications include endovascular treatments concerning cerebral vascular accidents, angioplasties of the carotid and placement of carotidian stents and intracranial stents. Knowledge of functional information is very useful for all these applications, before the surgical procedure is carried out, in order to make appropriate therapeutic decisions, and also during the procedure to be able to evaluate the effects of the treatment applied in real time, and to decide whether to stop it or to continue it if necessary.
Presently, the required functional information is obtained using magnetic resonance or calculated tomography devices, and not using an X-ray angiography or fluoroscopic device, whereas the procedure itself is carried out using an X-ray angiography device, and cannot be done with magnetic resonance or calculated tomography systems.
Means for processing can be used to deduce a three-dimensional model of the region of interest of the object, such as a patient, starting from a sequence of two-dimensional images thus acquired, in a known manner. In general, all that a medical practitioner, such as a surgeon, can use during a procedure is a single 3D model corresponding to a sequence of 2D images acquired at the beginning of the procedure.
Therefore, it is not possible to monitor the action of instruments on the anatomy of the object on which the procedure is being done (or the effects of the therapeutic action taking place on the treated tissues) on the 3D model. Thus, a medical practitioner can only obtain anatomic information from this method. Consequently, the object will firstly be examined either by magnetic resonance or by calculated tomography so as to obtain all functional information necessary to carry out the examination and the diagnostic. The object is then brought into the vascular operating theater for the therapy itself. This surgical procedure scheme is not sufficient to supply functional information that the medical practitioner might need during the procedure. At the present time, this problem is solved according to the state of the art by combining X-ray systems and magnetic resonance systems, for example, or calculated tomography systems, which lead to the combination of a vascular operating theater with a magnetic resonance or a calculated tomography unit, with an object operating table shared between the two systems. In these types of combined X-ray and magnetic resonance systems, for example, functional information is available in the magnetic resonance part while the surgical operation is done in the X-rays part. However, these systems are very complex, very expensive and occupy a lot of space (about the equivalent of two operating theaters). Consequently, in practice their use is limited to a very small number of locations.

Method and apparatus for determining functional parameters in a radiological apparatus

GE Medical Systems Global Technology Company, LLC


A computer includes a base having an exterior surface and a keyboard including input components mounted on a portion of the exterior surface. A palm rest area is provided adjacent the keyboard. A palm rest component is detachably mounted in the palm rest area. A numerical keypad is mounted in the palm rest component. A coupling connects the numerical keypad to supplement the input components of the keyboard.

The disclosures herein relate generally to computer systems and more particularly to a control pad provided in a palm rest.
Portable computer keyboards include alphabetical and numerical key functions. However, due to space restrictions, the numerical key functions are integrated into the rows of keys in the same format as the alphabetical key functions.
On larger keyboards, such as those used with desktop computers, the numerical key functions are separated from the alphabetical key functions in a numerical keypad layout such as that used on a touch dial of a telephone. This is advantageous because the numerical key array is familiar and can be used with one hand. Also, when a separate numerical keypad is available, it is not necessary to activate a function key as it is when using a portable computer keyboard.
Therefore, what is needed is a full-size keyboard for a portable computer including a numerical keypad. This feature greatly speeds up data entry, especially for accounting and drafting applications.
One embodiment, accordingly, provides a portable computer including full size keyboard functions having a numerical keypad. To this end, a portable computer includes a base having an exterior surface and a keyboard including input components mounted on a portion of the exterior surface. A palm rest area is provided adjacent the keyboard. A palm rest component is detachably mounted in the palm rest area. A numerical keypad is mounted in the palm rest component. A coupling connects the numerical keypad to supplement the input components of the keyboard.
A principal advantage of this embodiment is that no function key actuation is required, one handed operation is facilitated, and a numerical keypad layout is provided for faster data entry.


To allow a travelling vehicle to travel more smoothly, a host controller of a travelling vehicle system includes a first determination part which determines whether or not a second track selected by a first travelling vehicle is the same as a second track selected by a second travelling vehicle, and an entry permission issuing part that issues an entry permission into a switching track to the second vehicle after checking passage of the first vehicle through the switching track when the second track selected by the first vehicle is different from the second track selected by the second vehicle, and issues the entry permission into the switching track to the second vehicle regardless of receipt or non-receipt of the passage report from the first vehicle when the second track selected by the first vehicle is the same as the second track selected by the second vehicle.

1. Field of the Invention
The present invention relates to a travelling vehicle system for carrying a cargo along a track to transfer the cargo to a rack or the like.
2. Description of the Related Art
There has hitherto been known a travelling vehicle system for allowing a travelling vehicle to travel along a rail (one example of a track) hung on a ceiling, to carry a cargo in the vicinity of the ceiling. The travelling vehicle includes a lift stage liftably hung by means of a hanging member. The travelling vehicle transfers the cargo by lowering the lift stage to a placement member of a rack arranged along a travelling route of the travelling vehicle.
The track is installed in accordance with arrangement of the rack. The travelling route formed by the track typically includes a divergence part and a merging part (e.g., International Publication WO2009/142051). In the divergence part and the merging part, a switching track for connecting one track to one of a plurality of tracks is provided. The travelling vehicle selects a travelling route in accordance with a cargo loading/unloading instruction, to load and unload a cargo.
However, when the plurality of travelling vehicles are allowed to travel, there may arise a need for waiting before the switching track in order to obtain a permission to enter the switching track, which is problematic. From the viewpoints of efficiency in loading/unloading a cargo, reduction in operation time, and the like, it has been required to allow the travelling vehicle to travel more smoothly.


A method for transferring credits between gaming devices connected by a network to a host computer comprising. A player account accessible by the host computer is created. The player can access the account by inserting a card into a card reader at one of the gaming devices. A casino employee may apply credit to the account responsive to receipt of funds from the player. A predetermined amount of credit is transferred from the account to an EGM responsive to a command entered by the player at the EGM. Alternatively, the player applies a credit to the gaming device, typically by inserting bills into a bill acceptor. The credit and any awards resulting from gaming-device play are stored on a credit meter associated with the gaming device. Access to the account is terminated when the player withdraws the card from the card reader. A player initiates a request to redeem the balance stored on the credit meter by depressing a cash-out button. The balance on the credit meter is transferred to the player account if the cash-out button is pressed before the card is withdrawn, and is paid to the player via the gaming machine if the button is pressed after the card is withdrawn. All transactions are backed up on a database.

1. Field of the Invention
This application is a continuation-in-part of U.S. patent application No. 09/134,285, filed Aug. 14, 1998. The present invention relates to a method of accounting for player's wagers, jackpots, and awards on a network of gaming machines, and more particularly to such a method that facilitates cashless play of the gaming devices.
2. Description of the Related Art
There are several prior art systems implementing cashless gaming on electronic gaming devices, such as slot machines, that are connected to a host computer via a network. Such systems typically require a player to open a cashless gaming account with the casino prior to playing. The player must appear before a casino cashier who creates a player record on the host computer, receives an initial deposit from the player, and enters the deposit as a credit in the player account. The cashier also issues a cashless-wagering card to the player, who is now ready to begin cashless gaming.
The player selects a slot machine on the casino floor and inserts his or her card into a card reader associated with the slot machine. Each of the other slot machines also include associated card readers. Most prior art systems incorporate a security feature, such as a personal identification number (PIN), that must be satisfied before the system permits the player to draw on the credit in the account. In these prior art systems, the player enters his or her PIN on a keypad associated with the slot machine and card reader after insertion of the card. When the security feature is satisfied, the amount in the player's account appears on the display associated with the slot machine. The player may then draw on the account by initiating commands at the slot machine that transfer credits from the account to the slot machine. As the player transfers money from the account to the slot machine, the credit in the account decreases. If the player should be the recipient of a jackpot or other award at the slot machine, the conventional credit meter on the slot machine increments to add the jackpot or award to the balance on the credit meter.
When the player concludes playing, the balance is transferred from the credit meter to the player's cashless-wagering account responsive to a command initiated by the player. The player then withdraws his or her card and leaves the balance in the account for placing wagers on one of the slot machines at a future time, which may be a few hours, a few days, or longer.

Method of implementing cashless play of gaming devices interconnected by a computer network


A gate valve having a polymeric monolithic liner, the liner having cylindrical flange portions projecting from either side to form a fluid passageway through the liner, first and second housing portions forming a liner cavity, the liner being disposed in the liner cavity, a first face ring having a first cylindrical tubular portion and a first radially outwardly projecting, annularly extending face ring flange, the first tubular portion being received in the first annular flange portion of the liner, a second face ring having a second cylindrical tubular portion and a second radially outwardly projecting, annularly extending face ring flange, the second tubular portion being received in the second annular flange portion and a gate valve element slidably received in a valve element cavity formed in the liner.

1. Field of the Invention
The present invention relates to gates valves, particularly gate valves having a monolithic, polymeric liner.
Description of the Prior Art
Early gate valve construction involved a gate valve body machined from a single-piece casting, the single-piece casting forming a gate cavity in which a gate valve element was slidably disposed. In cases where the gate valve was used to handle corrosive products, it was common, and indeed necessary, to employ polymeric liners in the body in order to prevent damage to the castings. Examples of such corrosion-resistant valves employing polymeric liners are disclosed in U.S. Pat. No. 4,646,407 and patents cited therein. As taught in the prior art, the liners could be formed either by an in situ process using a one-piece valve body, such as disclosed in U.S. Pat. No. 4,646,407. Alternatively, as disclosed in U.S. Pat. No. 4,112,969, a one-piece liner could be molded separately from the valve body housing, the valve body housing being made of body halves that cooperate to form a cavity for the molded liner.
Gate valves having knife-type valve elements are frequently used to control the flow of slurries or similar solid liquid mixtures that, perhaps in addition to being corrosive, are abrasive and accordingly can cause excessive wearing of the polymeric liner. Accordingly, there remains a need for a gate valve having a monolithic corrosion-resistant liner wherein the liner is exposed to minimal contact with any abrasive material flowing through the valve.


A method and a device for continuously forming a heat exchanger that has a helically wound fin tube coil formed by a plurality of wraps. The device includes a rotationally driven mandrel with a central axis and a plurality of forming corners equiangularly disposed about and displaced from the central axis. The rotation of the mandrel is about the central axis in order to wind the fin tube coils onto the mandrel. A forming block is operably rotationally coupled to the mandrel and rotates with the mandrel. The forming block is also slideably engaged with the mandrel for axial translation a selected distance with respect to the mandrel. The forming block guides the winding of the fin tub coils onto the mandrel. An actuator is operably coupled to the forming block and causes the axial translation of the forming block. The axial translation is selectively timed with the rotation of the mandrel forming corners, whereby the wraps of the fin tube coil wound on the mandrel are iteratively axially translated with respect to the mandrel to define a continuous helix having a desired wrap pitch, shape, and spacing.

Helically wound fin tube coils are frequently used for outdoor heat exchangers in air conditioning units including cooling-only units and heat pumps. The wound coils provide an adequate heat exchange surface for the outdoor heat exchanger in an acceptable size, and can be relatively inexpensively manufactured, particularly for residential size units. The outdoor heat exchanger of the air conditioner frequently includes a plurality of circuits, and the coil may be wound in generally rectangular or annular shapes. The coil is disposed on a frame or base, with a guard disposed there around and a cover or grill disposed on the top thereof for protection, the guard, cover and base essentially defining the perimeter of the outdoor unit. Arranged within the space defined by the coil of conventional units are the compressor, outdoor fan, inlet and outlet manifolds, expansion valves, check valves, filters driers and, in a heat pump, a reversing valve, with appropriate interconnecting refrigerant lines therebetween. A compact outdoor unit is thus provided, requiring only hookup to the indoor heat exchanger and an electric power source. A typical coil is shown in U.S. Pat. No. 4,535,838 to Gray et al. This patent is commonly assigned with the present invention and incorporated by reference herein.
Typical manufacturing methods for such coils include winding the entire coil, either vertically or horizontally, from a continuous length of fin tubing, and thereafter determining in which wraps inlets and outlets for adjacent circuits should be made.
Virtually all helically wound fin tube coils are formed around a mandrel. A number of devices have been designed to noncontinuously perform the helical winding operations. Such devices include a tube guide mounted on a lead screw for helically advancing the coil onto the mandrel as shown in U.S. Pat. No. 5,099,574 to Paulman et al. U.S. Pat. No. 4,085,488 to Hanert et al. discloses a geared, translating tube guide that is driven on wheels across a surface to advance the tube onto a mandrel. A rotating cylindrical feed device is disclosed in U.S. Pat. No. 4,077,116 to Cunningham et al. The cylindrical feeder that is disclosed is oriented transverse to the mandrel and rotation of the feeder through approximately one-third of a revolution advances the tube onto the mandrel.
Several additional patents are of interest in showing the state of the art. There is a series of patents to McManus and to McManus et al., all of which are assigned to the same assignee and include U.S. Pat. Nos. 4,619,024; 4,619,025; 4,633,941; and 4,770,241. These patents disclose winding of the tubing around two spaced-apart upright posts. The posts with the wound tube in place are then advanced around a stationary mandrel to generate a partially closed four sided heat exchanger.
It would be a decided advantage in the industry to be able to continuously form helically wound fin tube coils. Further, it would be advantageous if the device performing continuous helical formation were adaptable to form heat exchanger coils having a selected number of sides. The device should additionally reduce the floor space required to manufacture the heat exchanger and should also reduce the number of operations needed for forming multi-circuit heat exchangers. It would also be desirable to cut the helical coil at selected locations in order to form circuits having a desired length.

Continuous heat exchanger forming method


An electrostatic (ES) device is described with electrodes that improve its performance metrics. Devices include ES generators and ES motors, which are comprised of one or more stators (stationary members) and one or more rotors (rotatable members). The stator and rotors are configured as a pair of concentric cylindrical structures and aligned about a common axis. The stator and rotor are comprised of an ensemble of discrete, longitudinal electrodes, which are axially oriented in an annular arrangement. The shape of the electrodes described herein enables the ES device to function at voltages significantly greater than that of the existing art, resulting in devices with greater power-handling capability and overall efficiency. Electrode shapes include, but are not limited to, rods, corrugated sheets and emulations thereof.

1. Field of the Invention
The present invention relates to flywheel energy storage systems, and more specifically, it relates to such systems employing electrostatic generator/motors.
2. Description of Related Art
Electrostatic generator/motors, as pioneered by Professor J. G. Trump, and, as described in the prior art, can be operated in either a generator or a motor mode (see, e.g., J. G. Trump, "Electrostatic Sources of Electric Power," Electrical Engineering 525, June 1947). Such devices have application to flywheels for bulk energy storage and robust motors, among myriad commercial and defense uses. This invention describes improved component configurations, electronic drive elements and parametric operational modalities for these devices, resulting in embodiments capable of functioning under the application of higher drive voltages than in the prior art, as well as with relaxed design rules and device constraints.
Electrostatic (ES) generators, an example of which is described in the prior art by the present inventor (U.S. Pat. No. 7,834,513 B2), operate with high electric potentials between stationary plates (stators) and moving plates (rotors), with each plate comprised of an annular array of electrodes. In general, for such ES generators, the achievable power output is determined primarily by four factors: (1) The voltage between the stator and rotor electrodes; (2) The maximum value of the capacitance of the electrode system, as determined by the geometry and material properties of the ES device; (3) The ratio of the maximum and minimum capacitance of the electrode system, Cmax and Cmin, respectively, that comprises the ES device; and (4) The operating frequency of the ES generator, as determined by the rotation speed of the rotor and the azimuthal periodicity of the segmented electrodes. Of these four factors, the key metric, in terms of device capability, is the first item listed above, namely, the operating voltage, as applied to the ES device. This follows, since it is known that for ES generator and motors, the characteristic electrical power that governs the operation of the device, be it the power output in the case of ES generators, or, the input drive power, in the case of ES motors, varies as the square of the peak voltage appearing between the opposing set of electrodes. A secondary metric pertains to the fourth item listed above, namely, the operating frequency of the device. In general, the operating frequency is equal to the product of rotation rate of the rotor and the number of annular electrodes about the circumference of the same.
Given that the ES devices cited in the above-noted prior art employ a so-called "resonance effect" to enhance the performance of the device, the third item listed above is not as critical a parameter as it is for other prior art ES systems that do not incorporate such parametric enhancements. Hence, in the present case, lower values of the capacitor ratio, Cmax/Cmin, can now be of practical use, as opposed to devices in the absence of parametric enhancements, whereby such low capacitance ratios may otherwise have been insufficient to achieve a given maximum power output, all else being equal. This invention teaches device embodiments that involve novel electrode geometries, which, relative to the prior art, can enable the application of greater ES device voltage levels across the electrodes (recall Item 1 above), as well as extending the range of allowable operating frequencies (recall Item 4 above). An example where such improved ES generator/motor systems can prove useful is in its application to flywheels for bulk energy storage.
In general, electrostatic (ES) generator/motors involve the use of an assembly of rotating and stationary elements that together comprise a condenser (or, capacitor), the capacitance of which varies periodically with the motion of the rotating elements relative to the fixed elements. An example of the prior art is shown in FIG. 1A (top view) and in FIG. 1B (Section A-A′: side view). Turning now to FIG. 1A, a circular array of fan-like stationary elements, 100, is depicted. Below this stationary array of elements is a similar circular array of elements, which is allowed to rotate about a vertical axis, referred to as the "rotor." FIG. 1B shows a cross-sectional side view of the overall ES structure, showing an embodiment consisting of a set of two rotors, 106, with each respective rotor also comprised of a circular array of fan-like elements. Each respective rotor plate 106 is bound on each circular surface by a respective pair of stationary arrays, of opposing, fan-like elements. In the dual-rotor example shown, there are two equivalent pairs of stators, arranged in a stacked configuration, with the central stator 104 common to both. One pair of stators is comprised of plates 100 and 104; and, the second pair of stators is comprised of plates 104 and 102, respectively. The rotor plates are allowed to rotate about an axis oriented orthogonal to the plane of the fixed plate(s), as shown in FIG. 1A.
As shown in FIG. 1B, the rotors, 106, are comprised of a set of annular fan-like elements, with each element having a thickness greater than the basic substrate of the rotor disc. In general, the thick fan-like sections elements of the rotor can consist of a metallic (conductive) material, a dielectric material or combinations thereof. Each pair of fixed fan-like elements, which comprises the opposing stationary plates, forms a capacitor of a fixed gap, g, in between which, each respective rotor rotates. As the moving discs revolve about its axis, the capacitance between each pair of opposing stationary plates will vary periodically, owing to differences in the effective gap dimension, g, and the properties of the rotor material, as each fan-like element of the rotor passes between each respective annular capacitor element in the array. Note that this basic configuration of FIGS. 1A and 1B can be classified as a planar geometry, since the effective capacitors are formed via the opposing planar surfaces of the stators and rotor.
In general, ES structures can be configured either as an electrostatic (ES) generator or as an electrostatic (ES) motor, dependent upon the details of an electrical circuit that includes this device. In the so-called "generator mode" of operation, rotation of the moving element results in the generation of an ac voltage arising from the basic equation for the voltage across a charged condenser when the capacitance varies with time, as indicated by Equation (1):
                              V                                (            t            )                          =                              q                          C                                            (                t                )                                                                                (            Volts            )                                              (        1        )            Here q (Coulombs) is the charge on the condenser and C(t) (Farads) is the time-varying value of the capacitance, the latter owing to the relative rotation of the rotor with respect to the fixed stators. If the capacitance varies periodically with time, then the ac output of the electrostatic generator will also be periodic, with an ac waveform that depends upon the geometry of the time-varying condenser and upon the charging circuitry that is employed.
The variable-capacity system described above is a "reciprocal" device, in that it is capable of functioning either as a generator or a motor, depending only upon the circuitry to which it is attached. As a generator, an example of which is an energy storage flywheel, the generator output is high-frequency alternating current, which can easily be converted to mains-frequency power. As an example, the high-frequency generator output can be first rectified to dc, with the resultant dc output driving an electronic inverter to produce a 60 Hz output, the latter suitable for commercially powered devices.
By reciprocity, operation of the system in the so-called "motor mode" requires a drive circuitry that generates a pulse-like waveform, which is synchronized with the rotation frequency and phase of the rotating elements.
In the electronic charging circuits such as those described in the prior art, dc power supplies are connected in series with charging inductors to the time-varying capacitors that form the ES generator. When these inductors are properly specified, an effective "parametric resonance" effect occurs, essentially coupling the LC-based charging frequency and the time-varying generator output, the latter being a function of the rotation rate and the number of fan-like annular elements in the array. This parametric effect resonantly increases the voltage gradient across the generator electrodes and enhances its power output and efficiency, far beyond that which can be achieved with the original resistive (instead of inductive) charging circuits such as those used in the pioneering work on ES generators by Trump.
FIG. 2 depicts an example of a prior art drive circuit, in which case a dual-balanced ES generator schematic diagram is shown. This circuit employs the parametric resonance effect noted in the prior art for enhanced device operation. The circuit has been shown by computer code simulation to enhance this parametric resonance effect. This approach enables the use of relatively low drive voltages, as well as relatively small capacitive ratios, Cmax/Cmin, to realize enhanced ES device performance over the prior art. In the circuit of FIG. 2 the parametric resonant effect is achieved by the proper choice of the value of the inductances in the circuit, based on the following: Starting at the point 254 in that circuit there is first an inductance (and its internal resistance), represented by 256 and 258. Next there are two time-varying condensers (260 and 360) connected in series. These condensers are followed by the inductance 356 and its internal resistance, with the circuit in question terminating at 354. This circuit represents a series-resonant electrical circuit, the resonant frequency of which will vary over a band of frequencies as the capacitors 260 and 360 vary synchronously between their maximum and minimum values. Strong parametric resonance occurs when that band of frequencies overlaps the frequency at which the capacities are varying. This latter frequency is determined by the product of the rotation speed of the system and the azimuthal number of periodic electrodes in the generator/motor (e.g., that number is 8 in FIG. 6A). If the rotation speed is constant fixed values can be used for inductances 256 and 356 of FIG. 2. If the rotation speed varies the inductance values must change accordingly. Such a change could be accomplished in several different ways, e.g. switching in or out additional series inductors, mechanically tuning the inductance (in the manner it was accomplished in early radio receivers), or by controlled saturation of the cores of iron-cored inductors. Fortunately, as analysis has shown, as long as there is an overlap between the operating frequency and the band of resonance the parametric resonance effect will be strong so that this inductance "tuning" need not be precise.
As an example, this circuit can be used to charge the ES device, as depicted in the prior art embodiment of FIG. 1A and FIG. 1B. In this case, each respective variable capacitor, 260 and 360, in FIG. 2 corresponds to a respective variable capacitor in the device shown in FIG. 1B, with each such variable capacitor formed by stationary plates 100 and 104, or by stationary plates 102 and 104, within which revolves a respective rotor plate 106.
Referring again to FIG. 2, each of the two balanced portions of the circuit is comprised of a time-varying capacitor, C(t). 260 [360], a fixed coupling capacitor, C, 268 [368], and a charging inductor, L, 256 [356], with each inductor possessing an internal resistance, represented by a resistor R, 258 [368], which together drives a load 400. By using the load to provide electrical coupling between the two circuit portions, the net effect is to lower the optimum load impedance, while at the same time, increasing the output power.
Each respective time-varying capacitor, C(t), consists of a pair of fixed stator assemblies, between which is an elongated rotor. Owing to the balanced nature of the circuit in the prior art example, the rotors operate at a virtual ground potential and, therefore, do not require a direct electrical connection to ground. Finally, the input to each portion of the balanced circuit is driven by a respective power supply at a voltage, V, 252 [352], each of which is of an opposing polarity.

Electrode geometry for electrostatic generators and motors

Lawrence Livermore National Security, LLC


In one aspect an apparatus for determining a distance between a first borehole and a second borehole during drilling of the second borehole is disclosed that in one embodiment includes a magnet on a drilling tool that rotates in the second borehole to induce a primary magnetic field in a magnetic object in the first borehole, a substantially stationary sensor on the drilling tool that detects a secondary magnetic field from the magnetic object responsive to the induced primary magnetic field, and a controller that determines the distance between the first borehole and the second borehole from the detected magnetic field. In another aspect a method of determining a distance between a first borehole and a second borehole, the in one embodiment includes inducing a primary magnetic field in a magnetic object in the first borehole using a rotating magnet in the second borehole, detecting a secondary magnetic field from the magnetic object responsive to the induced primary magnetic field using a substantially stationary sensor in the second borehole, and determining the distance between the first borehole and the second borehole from the detected magnetic field.

1. Field of the Disclosure
This disclosure relates generally to apparatus and methods for determining a distance to a pre-existing wellbore and controlling drilling operations based on the determination.
2. Background of the Art
In the process of drilling wells (also referred to as wellbores or boreholes) for hydrocarbon production, it is common to drill a second well in a predetermined relationship to an existing well. An example of this may be when a blowout occurred in the existing well. Two approaches may be taken to control the blowout. One method is to use explosives at the surface and snuff out the fire in the burning well. This procedure is fraught with danger and requires prompt control of hydrocarbons flow in the well. The second method is to drill a second borehole to intersect the blowout well and pump drilling mud into the blowout well. This is not a trivial matter. An error of half a degree can result in a deviation of close to 90 feet at a depth of 10,000 feet. A typical borehole is about 12 inches in diameter, a miniscule target compared to the potential error zone.
Another situation in which accurate placement of a secondary well relative to a preexisting well is desired for secondary recovery operations. For various reasons, such as low formation pressure or high viscosity of hydrocarbons in the reservoir, production under natural conditions of hydrocarbons may be at uneconomically low rates. In such cases, a second borehole is drilled to be substantially parallel to the pre-existing borehole. Fluid such as water, CO2 is then injected into the formation from the second borehole and the injected fluid drives the hydrocarbons in the formation towards the producing borehole where it may be recovered.
In the second category are passive ranging techniques that do not require access to the pre-existing well while drilling the second well. The techniques normally utilize a relatively strong magnetism induced in the casing of the pre-existing well by the Earth's magnetic field. The signal due directly to the earth's magnetic field is a problem, limiting the accuracy of this measurement. Residual magnetism of the casing introduces additional uncertainties.
The present disclosure discloses apparatus and methods for determining distance from a pre-existing wellbore without accessing the pre-existing well.

Apparatus and methods for well-bore proximity measurement while drilling