An apparatus and method provide deposition on a surface by angled sputtering using a collimation grid having angled vanes which limit the distribution of trajectories of particles in at least one coordinate direction around a central axis oriented at an angle of less than 90.degree. to said surface; resulting in improved uniformity of deposition and/or selective favoring of deposition on surfaces at a high angle to the deposition surface (e.g. sidewalls). Substantially parallel orientation and uniform spacing of the sputtering target and deposition surface provides good uniformity of results over the deposition surface. The angled trajectories of sputtered particles provides improved deposition on sides of upstanding mandrel features and filling of recessed features of high aspect ratio, especially when the collimation grid is rotated about an axis generally perpendicular to the deposition surface. Angled, collimated deposition also allows for control of deposition at potentially sub-lithographic feature sizes by using portions of features as a mask with deposition being performed only on remaining exposed portions of features or deposition on selected sides of a mandrel feature. Sidewall image transfer techniques may thus be extended to non-symmetrical and singular features. At very shallow angles to the deposition surface, deposited material has a fibrous texture with greatly increased effective surface area.

1. Field of the Invention
The present invention generally relates to the deposition of materials on a surface having severe topography, including the formation of patterns of potentially sub-lithographic dimensions and, more particularly, to particular arrangements for material deposition by sputtering especially for treatment of surfaces and fabrication of micromachines and semiconductor devices at high integration density.
2. Description of the Prior Art
In the field of integrated circuit and micromachine fabrication, many steps in highly complicated processes involve the removal or deposition of material and many techniques are known and widely practiced for the achievement of either result. In general, techniques for obtaining either result are classified as isotropic or anisotropic to indicate whether or not they can be expected to proceed in a preferred direction. Anisotropy can also be induced by convoluted surface topography with isotropic processing. Thus, in practice, most of these techniques, particularly for material deposition, are neither ideally isotropic nor ideally anisotropic. Deposition rates can also be significantly affected by the topography of the surface(s) on which deposition is to be performed, particularly in sputtering techniques where material is eroded from one surface (referred to as a target) and redeposited on another surface.
As is well-understood in the art, the rates of material deposition in sputtering processes are highly dependent on the angle of incidence of atoms or ions at the surface where deposition is to occur. That is, the likelihood of deposition of a particular atom or ion at a particular location on a surface increases as the angle of incidence approaches perpendicular to the surface at that location. Therefore, when the trajectories of sputtered particles are widely distributed, deposition will appear to be severely affected by surface formations and topographies which reduce the number of particles which reach particular regions of the surface. On the other hand, when the trajectories are confined, such as with collimation, deposition on surfaces substantially perpendicular to the particle trajectories as established by the collimation will be strongly preferred.
Severe surface topographies thus present substantial difficulties in obtaining desired deposits of material, whether the goal of the particular deposition process is uniformity of deposit thickness or high selectivity between surfaces on which deposits are to be formed. This problem is aggravated since, particularly at very small feature sizes comparable to minimum feature sizes available with current lithographic processes, the surface topography is dynamically changed by the thickness of the deposit as the deposition process is carried out.
More specifically, as integration densities have increased and feature sizes have decreased in integrated circuits, for example, it has become necessary to perform filling of relatively high aspect ratio (e.g. greater than 1:1 ratio of feature depth to transverse dimension of the feature) trenches or apertures in a substrate or layer. Isolation trenches and trench capacitors are examples of structures requiring such trench filling (generally with SiO.sub.2 and polysilicon, respectively) typically by chemical vapor deposition and other known techniques, including sputtering. However, chemical vapor deposition is currently considered to be much preferred over sputtering to fill severe topography for the reasons noted above. Similar high aspect ratio features and requirements for filling and/or deposition on severe topographies are also commonly encountered in micromachines.
Sputtering techniques are currently used principally for the deposition of metal for the formation of conductor patterns and collimation is known to improve deposition on severe topographies. However, collimation itself reduces the deposition rate of sputtered material, particularly on the recess (e.g. trench) sidewalls and develops an overburden or overhang at the top edges of the trench which causes non-uniformity across the bottom of the trench or aperture. In comparison, with uncollimated sputtering, the surface topography alters trajectory distribution of sputtered particles at different locations on a surface (hereinafter referred to as a "deposition surface" which may or may not feature severe topography as distinguished from the individual surfaces of particular features which may constitute severe topography of the deposition surface) which, in turn, causes deposition on trench or aperture sidewalls to proceed at a faster rate near the top of the trench, forming an overburden at the top of the trench, which similarly causes thinner and non-uniform deposition at the trench bottom and reduces the rate at which deposition occurs.
Further, with either collimated or uncollimated sputtering, because of deposition on sidewalls near the top of the trench or aperture, deposition in the corners of the bottom of the trench or aperture and in similarly shaped portions of severe surface topography is particularly compromised. When filling of trenches or apertures is attempted, these variations from uniformity of deposition may cause defects such as so-called keyhole voids within the incompletely filled trench or aperture. Layered structures, particularly for conductors crossing severe topography will also be formed with reduced thickness at a point where the surface orientation abruptly changes (e.g. from horizontal to vertical).
Perhaps more importantly, as integration density has increased, the "value" of surface area on the chip or features which may be formed thereon has increased and a technique to increase the usable area of a chip of given dimensions is critical to increased "device counts" for particular integrated circuit designs. In an attempt to accomplish such an effective increase in area where devices can be formed, several types of structures have been proposed but which require the ability to form substantially uniform deposits on surfaces which are at a large angle to the major dimension (e.g. deposition surface) of a wafer, such as the sidewalls of a trench or aperture. While collimated sputtering in a direction perpendicular to the wafer surface is known to favor deposition at the bottoms of such formations, sidewall deposition continues to be non-uniform.
Additionally, for maximum integration density of integrated circuits or the highest degree of miniaturization of micromachines, it is conventional to form at least some of the trenches and apertures or other features at or near the minimum feature size obtainable with the lithographic technology chosen for the design. Therefore, in such a case, any structure formed within the trench would be, necessarily, of sub-lithographic dimensions, at least for the same lithographic technology. Further, process complexity and cost increases dramatically for lithographic processes as minimum feature size is decreased. Criticality of registration is also increased and process tolerances reduced along with potential adverse impact on manufacturing yields.
Some techniques are known for production of so-called sub-lithographic feature sizes. A widely known technique, commonly referred to as sidewall image transfer (SIT), uses a combination of isotropic and anisotropic processes to form narrow sidewalls on a projecting feature, known as a mandrel, which may be later removed. (Similar topography is presented by a recessed feature, such as a trench, although trenches must remain in the structure of the design. Formations of the sidewalls of a trench are generally referred to as "spacers".) However, the sidewall structures can only be formed symmetrically in closed patterns on all sides of the feature (e.g. seen as pairs in the cross-section of a mandrel or trench). While closed patterns have found substantial utility in self-aligned semiconductor processes and can be modified with other lithographic processes such as masked etching, no process has existed for providing a single sub-lithographic pattern by sidewall image transfer. For example, the utility of angled sidewall deposition at an angle of 5.degree. to 25.degree. to the substrate surface in combination with angled impurity implantation is suggested for forming a field-effect transistor having an extremely short channel and gate alignment of improved accuracy in U.S. Pat. No. 4,532,698 to Frank F. Fang et al. which is assigned to the assignee of the present invention. However, the technique disclosed therein relies on the shallowness of the angle of deposition to minimize the thickness of deposition on horizontal surfaces so that any substrate deposition can be etched away without significant change of thickness of sidewall deposition and thus effectively assumes only a single vertical surface is available (at least within a distance which would severely limit integration density) for formation of a sidewall deposit.
In any case, known processes for carrying out SIT techniques are complicated and require close process tolerances. Further, SIT techniques may be compromised by non-uniform deposition on sidewall surfaces and/or variation from ideal anisotropy of etching applied to remove material other than that deposited on vertical surfaces, particularly when the sidewall deposit is reduced in thickness significantly below dimensions available with lithographic techniques.
Other applications such as micromachines also require structures which are of a geometry which may or may not have utility in integrated circuits. For example, a sub-lithographic T-shaped structure may provide benefits in electronic devices operating on vacuum tube rather than semiconductor principles for application in environments where strong electromagnetic fields may be encountered. Such a shape cannot be formed by sidewall image transfer since that process provides no selectivity between portions of the sidewall. Likewise, micromachine impellers may derive increased efficiency from particular shapes which cannot be formed by SIT techniques.
Numerous applications are also known where efficiency and/or degree of size reduction can be increased by surface treatments. For example, it is known that techniques which roughen the surface of material, such as the production of so-called hemispherical grains can increase the effective surface area and the capacitance value of capacitors of a fixed overall size. Other applications in which performance depends on increased surface area include but are not limited to solar-cells, material detectors, catalysts, fluid filters, and the production of porous surfaces, such as in some types of filters. Surface topography as well as area may also be of importance, for example, in optical or ultrasonic applications. Known surface treatment techniques are, however, somewhat limited in the amount of effective increase of surface area which can be achieved. For example, while still a highly significant improvement in capacitors, hemispherical grain provides an effective surface area increase which is limited to about 40%.
Some research has also been done in performing material deposition techniques at an angle. However, angled evaporation or sputtering has generally resulted in poor uniformity over large wafer areas required for economical throughput of semiconductor processing reactors. This problem has been attributed, in regard to uncollimated sputtering, to non-uniformities in the trajectories of particles ejected from the sputtering target which generally form lobes which are directed in dependence on grain orientation in the target. Even with collimated sputtering or attempts to exploit preferred angles of particle ejection from a sputtering target, directivity of the particles toward the deposition surface on which material is to be deposited may be lost over distances as short as about two centimeters, limiting the area which can receive relatively uniform deposition as distance from the sputtering target varies.
It should also be noted that collimated sputtering for filling of trenches, apertures and other severe surface topography and angular deposition techniques as practiced to date have been mutually exclusive processes. Collimation requires use of a collimation grid generally having apertures with an aspect ratio of 1:1 or greater (although lower aspect ratios may be used for some applications when necessitated by a trade-off between deposition rate and degree of particle directivity) and limits the angular distribution of trajectories of particle to be deposited. Such limitation of the angle of particle trajectories would require a substantial distance from the target to the wafer if a collimation grid were to be applied to the target during angled sputtering in order to obtain coverage for the transverse dimension of the wafer surface. If the deposition surface is inclined to the sputtering target and the direction of collimation of the collimation grid as has generally been done, substantial differences in distance from the sputtering target to the deposition surface will be presented at different locations on the deposition surface.
For this reason, collimated sputtering is principally performed only in a direction perpendicular to the deposition surface on which material is to be deposited, often with a grid formed with hexagonal cells in a "honeycomb" pattern for collimation over the wafer surface since such a collimator may be placed close to the surface. Accordingly, no technique is currently available which can favor deposition on sidewalls of upright formations, uniformly provide angled material deposition, form substantially uniform depositions on vertical sidewalls over the surface of a wafer or provide selectivity between portions of sidewalls.

Method for selective material deposition on one side of raised or recessed features

International Business Machines Corporation


A system is provided for downloading pushed content includes a terminal capable of receiving service loading content that identifies download content and has a digital signature. The terminal is capable of authenticating the service loading content based upon the digital signature, and if the service loading content is authenticated, pulling the download content to the terminal. In this regard, the terminal is capable of authenticating the service loading content, and pulling the download content, in response to receiving the service loading content and independent of interaction from a user of the terminal. The terminal can also be capable of determining if an interruption occurs in receiving the download content such that the terminal receives less than the entire download content. And if an interruption occurs, the terminal can be capable of recovering the download content such that the terminal receives the plurality of data packets.

The modern communications era has brought about a tremendous expansion of wireline and wireless networks. Computer networks, television networks, and telephony networks are experiencing an unprecedented technological expansion, fueled by consumer demand. Wireless and mobile networking technologies have addressed related consumer demands, while providing more flexibility and immediacy of information transfer.
Current and future networking technologies continue to facilitate ease of information transfer and convenience to users. The proliferation of local, regional, and global networks such as the Internet has availed a sea of information to society. These networking technologies have expanded to increasingly include wireless and mobile technologies. Through these networks, information can be downloaded to desktop systems, wireless systems, mobile systems, etc. For example, information available via the Internet can now be downloaded onto mobile wireless units, such as cellular telephones, personal digital assistants (PDAs), laptop computers, etc. One such technology facilitating the transfer of Internet content to and from wireless devices is the Wireless Application Protocol (WAP), which integrates the Internet and other networks with wireless network platforms. Generally, WAP is a set of protocols that accounts for characteristics and functionality of both Internet standards and standards for wireless services. It is independent of wireless network standards, and is designed as an open standard. WAP bridges the gap between the wireline Internet paradigm and the wireless domain, to allow wireless device users to enjoy the benefits of the Internet across both platforms.
Second generation wireless service, often referred to as 2G wireless service, is a current wireless service based on circuit-switched technology. In this regard, 2G systems, such as Global System for Mobile communications (GSM) and Personal Communications Services (PCS), use digital radio technology for improved quality and a broader range of services over first generation mobile technologies. Third generation wireless service, often referred to as 3G wireless service, refers to a set of digital technologies that promises improvements in capacity, speed and efficiency by deploying new packet-based transmission methodologies between terminals and the network. Users of 3G devices and networks will have access to multimedia services such as video-on-demand, video conferencing, fast web access and file transfer. Existing and future services are, and will continue to be, provided by network service operators who make services and applications available to mobile device users via the network.
One particular service feature currently available for communicating information is a "push" feature (also known as a "notification" feature or "alert" feature). In a typical client/server model, a client requests a service or information from a server, which then responds in transmitting information to the client. This is generally referred to as "pull" technology, where the client pulls the information from the server. For example, entry of a Uniform Resource Locator (URL) at a client device which is then dispatched to the server to retrieve the associated information is a pull transaction.
In contrast, "push" technology generally refers to a means to transmit information to one or more devices without a previous user action. Thus, there is no explicit request from the client before the server transmits its information, and therefore push technology essentially includes server-initiated transactions. Push technologies can be used in connection with various protocols and communication technologies. For example, some representative push technologies include Short Message Service (SMS), Wireless Application Protocol (WAP) Push, Multimedia Messaging Service (MMS), Session Initiation Protocol (SIP), as well as others.
In accordance with the WAP push architecture, for example, content delivery is triggered by a push initiator (server), which sends a push message to the client to thereby notify the client of an incoming transmission. Based on the parameters in the push message, then, the client may start the downloading process to thereby download content from the push initiator. More particularly, after a download session has been established between a client and push initiator, a service indication can be delivered to the client, where the contents of the service indication may be presented to the user of the client (e.g. "Incoming advertisement, want to receive?"). Based upon the service indication presented to the user, then, the user can either to accept or decline the service. If the service is accepted, the content can be downloaded from the push initiator to the client. For more information on the WAP push architecture, see, for example, Wireless Application Protocol Forum, WAP Push Architecture Overview, WAP-250-PushArchOverview-20010703-a, the contents of which are incorporated herein by reference in its entirety.
Whereas traditional push technologies are adequate to push content to clients, such technologies suffer from drawbacks. In this regard, conventional push technologies, such as that provided by the WAP push architecture, require client (or user of the client) interaction to effectuate the download of content from the push initiator to the client (i.e., end-user needs to accept the pushed content before the content delivery). And for various services and content, it is desirable to push content to clients without requiring an end-user to explicitly accept the content at the download time.
As a solution to the drawback of requiring end-user interaction to receive pushed content, service loading technologies, such as that defined by WAP, can be utilized by a client to download content without end-user interaction. In accordance with WAP, service loading allows clients to receive content without user intervention. In this regard, a push initiator pushes service loading content to a client, which upon receipt of the service loading content, automatically downloads (i.e., "pulls"), from an origin server, content identified by the service loading content. For more information on the WAP service loading architecture, see, for example, Wireless Application Protocol Forum, Service Loading, WAP-168-ServiceLoad-20010731-a, the contents of which are incorporated herein by reference in its entirety.
Although service loading technologies solve the drawback of requiring end-user interaction to receive content, such technologies also have drawbacks. In this regard, subscribed/non-subscribed push type services (e.g., e-mail) are prone to spamming. As well known, spamming generally refers to the receipt of unsolicited services, such as bulk email. Thus, it would be desirable to develop a system and method of pushing content to a client without end-user interaction, while reducing the likelihood of receiving unsolicited services or content.
As is well known, many current techniques for downloading content over the air assume, at least to some extent, that such content is downloaded in one communication, or download, session. For example, current Open Mobile Alliance (OMA) techniques for downloading content in accordance with the Over the Air (OTA) protocol assume, at least to some extent, that such content is downloaded in one download session. However, if the client is downloading large content, the time to download the content typically increases, thus increasing the probability that the client will encounter some type of error or interruption in transmission during the download process. For example, end users can interrupt the transmission of downloaded content if such end users desire to utilize the client for an alternative purpose, such as to operate an application other than that receiving the content. Also, for example, an unexpected event, such as client error (e.g., dead battery, halt, crash, etc.) or network failure (e.g., out of the geographic coverage area, etc.) can interrupt the transmission of download content.
Conventionally, when content is downloaded in a single download session, if an error or interruption in transmission occurs during the download process, the client must restart the download process to completely download the content. For example, if a client encounters an error or other interruption in downloading content having a size of thirty-two mega-bytes over a General Packet Radio Services (GPRS) network, the client typically must restart the download to receive the content, even if the client had already downloaded significant portion of the content before the error or interruption. Several techniques, such as File Transfer Protocol (FTP) techniques, have been developed to recover a download session that has encountered an error or interruption. Such techniques, however, are merely designed to recover a download session that has encountered a network connection error (e.g., modem failure) and do not permit the recovery of download sessions that are halted for other reasons. Thus, it would be desirable to develop a system and method that is capable of not only pushing content to a client without end-user interaction and while reducing the likelihood of receiving unsolicited services or content, but is additionally or alternatively capable of recovering a download session that has encountered a client error, as well as a network error. It would also be desirable for such a system and method to be capable of providing fast authentication of a user desiring to receive content and justify that user has right to that content or service. In addition, it would be desirable for such a system to be capable of facilitating a user receiving paid content without having to repay for the content in the event a download session of such content encounters an error.

System, method and computer program product for downloading pushed content


A KASER (Knowledge Amplification by Structured Expert Randomization) engine reaches conclusions in a semantic format or which take the form of a series of rules. The conclusions are parsed into an array structure having a hierarchical order of validity. A set of inserted rules is received as an initial rules array and are configured so that an antecedent comprises a non-empty, sorted set and a consequent comprises a non-empty sequence. A hierarchy of validity for the rules is determined and the rules are sorted according to the hierarchy. At least one rule set which optimizes the selection of rules is determined, with the rule set meeting predetermined validity requirements, and the rules are ordered in an order of validity, such as an order based on a maximal length antecedent set as a highest rank.

1. Field
This disclosure relates to an expert system for deriving possibilities and conclusions, in which a hierarchical structure is used for deriving proposed conclusions.
2. Background
First-generation expert systems are known in the data base processing arts as production systems where the knowledge base and inference engine are disjointed. Second-generation expert systems are improved in the art to include a rudimentary learning capability, which may be implemented by the interpretation of grids or by user query. Third-generation expert systems are further improved to provide for rule base learning through the use of deductive and inductive processes.
Conventional analysis of information includes manually combing through vast databases and unstructured text/reports. An alternative method would be to use a database computer language such as structured query language (SQL) to perform directed mining operations. This approach is not fully general, is difficult and costly to maintain, and does not provide a capability for linking database events. Moreover, such database mining is less than optimal at rendering conclusions and probabilities.
Rendering conclusions can require association of ostensively random events or events which appear to be random. An example of event-related activity for detection would be detection based on a previously acquired signature of the activity.
Conventional expert systems require that all knowledge be hand-tailored and manually checked for validity and consistency. In particular, conventional alternatives are either not creative, or do not reason using symbolic knowledge; i.e., computing with words.
Conventional analysis of information includes manually combing through vast databases and unstructured text/reports. For purposes of data analysis, a given concept may be broadly defined, or defined within a particular context. This may or may not have a direct correspondence to a general definition of the concept, but relates to a specific aspect of the concept. Therefore, substantial human analogical reasoning was required.
U.S. Pat. No. 7,047,226, to Rubin, titled "System and Method for Knowledge Amplification Employing Structured Expert Randomization" describes a Type 1 Knowledge Amplification Employing Structured Expert Randomization (KASER) engine, and describes the general concept of a Type 2 KASER engine. The Type 1 KASER is described as allowing the user to supply declarative knowledge in the form of a semantic tree using single inheritance. In a Type 1 KASER, words and phrases are entered into the system by an operator by means of, for example, pull-down menus. In this manner, semantically identical concepts (e.g., Hello and Hi) may be entered with equivalent syntax by the operator to avoid diluting the learning efficiency of the KASER.
Accordingly, there remains in the art a clearly-felt need for an expert system architecture that may automatically expand the rule base without the concomitant data input burden associated with error correction needed to optimize expert system performance. An expert system that includes learning means for acquiring a rule system that functions as a larger virtual rule system with reduced error probability has, until now, been unavailable in the art. These unresolved problems and deficiencies are clearly felt in the art and are solved by the present subject matter in the manner described below.

System and method for type 2 KASER (Knowledge Amplification by Structured Expert Randomization)

The United States of America as represented by the Secretary of the Navy


A neuronal cell death induced by an oxidative glutamate toxicity is substantially inhibited by administrating to an mammal an effective amount of a phenylenediamine derivative compound of formula (I), wherein R is phenyl or butyl.

1. Field of the invention
The present invention relates to a method for inhibiting a neuronal cell death induced by oxidative glutamate toxicity.
2. Discussion of the Background
Resistance to oxidative stress often determines neuronal survival in the brain. Thus, antioxidants appear to be promising neuroprotective compounds against neurodegenerative diseases. For example, N,N′-diphenyl-p-phenylenediamine (DPPD) reportedly exerts cytoprotective effects against oxidative stress, possibly by acting as an antioxidant. DPPD provides hydrogen thereby scavenging free radicals, and protects cells from oxidative stress. However, there is no critical biological evidence to show that its antioxidant ability actually prevents cell death.
Oxidative stress, defined as the accumulation of reactive oxygen species (ROS) caused by enhancement of ROS production or by suppression of ROS destruction, plays a pivotal role in neurodegeneration associated with ischemia, trauma, and other neurodegenerative diseases [1-4]. The accumulation of ROS in neurons results in lipid peroxidation, protein oxidation, DNA damage, and finally cell death [1-4]. Thus, antioxidants are one of the potential targets of drug development for neuroprotection [2-3]. Basically, antioxidants are categorized into two distinctive groups: 1) hydrophilic and 2) lipophilic ones. Hydrophilic antioxidants, such as vitamin C or glutathione, are believed to react with water-soluble ROSs (superoxide anion [O2-], or hydrogen peroxide [H2O2]). In contrast, lipophilic antioxidants are believed to suppress lipid peroxidation. Two of the latter, vitamin E and N,N′-diphenyl-p-phenylenediamine (DPPD, FIG. 1) are believed to become inserted into the cell membrane and maintain membrane integrity, thereby providing potent cytoprotective actions against oxidative stress [1]. In vivo, DPPD protected animals against various insults initiated by oxidative stress resulting from brain or renal ischemia or carbon tetrachloride treatment [5-7]. Also, DPPD exerted a cytoprotective effects in vitro against oxidative stress on various types of cells including neuronal cell lines PC12 and HT22 [8-15]. For example, DPPD at μM concentrations protected PC12 cells against lipid peroxide, which protection was associated with a decrease in intracellular ROS levels [13]. These results suggest that DPPD protects neuronal cells against oxidative stress by acting as an antioxidant in both in vivo and in vitro systems [5-15].
There exists a need for methods of substantially inhibiting a neuronal cell death induced by an oxidative glutamate toxicity.

Method for inhibiting neuronal cell death induced by oxidative glutamate toxicity

Incorporated National University Iwate University


A position detector detects the position of a die opening/closing device on a machine frame of an injection molding machine. A shielding object is provided between the position detector and an oil scattering source of a mechanical section of the injection molding machine.

1. Field of the Invention
The present invention relates to an injection molding machine including a position detector of a die opening/closing device.
2. Description of the Related Art
Japanese Patent Application Laid-Open No. 5-437 discloses a technique in which a position detector for detecting a position of a die opening/closing device is provided on a machine frame of an injection molding machine and the die opening/closing device is automatically moved to a position corresponding to the thickness of a die mounted on the injection molding machine. Therefore, a conventional technique will be described with reference to FIG. 3.
A die clamping device is provided on a base 38, a base portion of a front platen (not illustrated) is fixed to the base 38, and a base portion of a rear platen 33 is placed in a rail 39 on the base 38. Here, the die clamping device is movable in the front-to-back direction so as to adjust the thickness of the die. A feeding screw 30 is formed in each of the rear ends of tie-bars 34, and the feeding screws 30 extend backward from the rear platen 33. A tie-bar nut 31 provided with a sprocket attachment is axially supported to the rear surface of the rear platen 33 so as to rotate at the constant position in the axial direction in association with a position where the rear portion of the tie-bar 34 protrudes from the rear surface of the rear platen 33. Then, the tie-bar nut 31 is threaded into the feeding screw 30 formed in the tie-bar 34.
An endless chain is wound around four tie-bar nuts 31 which are threaded into the feeding screws 30 of four tie-bars 34, and the chain is driven by a die thickness adjustment servo-motor 32, so that these four tie-bar nuts 31 rotate in a synchronization state. Accordingly, when the die thickness adjustment servo-motor 32 is driven, the tie-bar nut 31 rotates, and the rear platen 33 moves forward or backward by the pitch of the feeding screw 30. Meanwhile, when the die thickness adjustment servo-motor 32 is stopped, the tie-bar nut 31 does not rotate, and the rear platen 33 is fixed to the current position.
A measurement portion 37a of a linear scale 37 is horizontally fixed to the side surface of the rear platen 33, one end of a bar-shaped scale portion 37b is fixed to one point (a point P) on the base 38, the other end of the scale portion 37b is fitted into the measurement portion 37a, and hence the distance between the point P and one point (for example, an engagement point Q between the rear platen 33 and the tie-bar 34) of the measurement portion 37a is measured. The measurement value obtained from the measurement portion 37a is input to a numerical controller 40 of the injection molding machine. The numerical controller 40 performs a control involving with the injection molding operation, and the memory also stores an operation program in a die thickness adjustment mode. When the die clamping servo-motor 36 is driven, the cross head member 35 of the toggle mechanism moves forward or backward.
Furthermore, there is a case in which a geared motor is used instead of the die thickness adjustment servo-motor. Here, one gear engages with four tie-bar nuts, and the gear is driven by the die thickness adjustment servo-motor or the geared motor.
In the injection molding machine, the position of the die opening/closing device is adjusted in accordance with the thickness of the installed die. The position may be adjusted by a method of moving the die opening/closing device while an operator checks the movement with his/her eyes. However, since the die opening/closing device generally moves at a low speed, it takes a time for the movement, and hence the operator feels burdensome.
In order to solve this problem, according to the conventional technique, a die contact position is searched in a manner such that an injection molding machine automatically moves a die opening/closing device to a position corresponding to the maximum thickness of the die mounted on the injection molding machine and then gradually moves the die opening/closing device in a direction in which the die thickness decreases. However, since the die opening/closing device moves at a low speed, it takes a time for the movement. As a result, there is a disadvantage that a die replacement time increases compared to the case where the position is manually adjusted by the operator.
As a means for solving this problem, Japanese Patent Application Laid-Open No. 5-437 discloses a technique of detecting the position of the die opening/closing device on the machine frame by means of a position detector provided on the machine frame and automatically moving the die opening/closing device to a position corresponding to the thickness of the die mounted on the injection molding machine. According to this technique, the die opening/closing device does not need to be moved to a position corresponding to the maximum thickness of the die mounted on the injection molding machine and the die replacement time maybe shortened compared to the conventional technique.
However, there is a concern that the position detector may be contaminated by the oil scattering from the mechanical section of the injection molding machine such as the die opening/closing mechanism driving ball screw or the push mechanism driving ball screw of the die opening/closing device at the position on the machine frame provided with the die opening/closing device or the position in the vicinity thereof and hence the detection precision may be adversely affected.

Injection molding machine including position detector of die opening/closing device


A phase-frequency detector (12) is configured for operating at a high frequency. A transition of a clock signal (REF CLK) is detected by a first latch (52) and a signal UP is generated. A transition of a feedback signal (FBK) is detected by a second latch (56) and a signal DOWN is generated. An logic circuit (64) detects the signals UP and the DOWN and generates a reset signal (RESET). A pulse-width of the reset signal (RESET) is controlled and limited by the logic circuit (64) to provide a faster response time for setting the first and second latches (52 and 56) to a state that allows detection of the phase and frequency differences between the clock signal (REF CLK) and the feedback signal (FBK).

The present invention relates, in general, to integrated circuits and, more particularly, to phase-frequency detector circuits.
Phase-locked loops (PLLS) are widely used for clock generation in data communication systems, local area networks, data storage applications, disc drives, and microprocessors. The five parts of a phase-locked loop typically include a phase-frequency detector (PFD), a charge-pump, a low-pass loop filter, a voltage-controlled oscillator (VCO), and a programmable divider. The PLL minimizes the skews of the phase and the frequency between an externally supplied reference clock and a feedback signal that is generated by the VCO and transferred to the programmable divider.
The PFD monitors the relative timing between the edges of the reference clock and the feedback signal and generates two output pulses of varying width that indicate whether the reference clock leads or lags the feedback signal. The output pulses are used for adjusting an analog signal that controls the VCO operating frequency, thus minimizing the skews of the phase and the frequency between the reference clock and the feedback signal from the programmable divider.
The phase offset and maximum frequency of the PLL system can be limited by the linearity and frequency response of the PFD. Typically, the PFD uses latches to detect the phase-frequency relationship between the reference clock and the feedback signal. The latches switch states at the transition edges of the reference clock and the feedback signal. A comparison of the outputs of the latches determines both the width of the pulses that are generated at the output of the PFD and the phase relationship between the reference clock and the feedback signals, i.e., whether the feedback signal leads or lags the reference clock. After the comparison of the latched output signals, the latches are switched to a state that allows detection of the next transition of the reference clock and the feedback signal edges. The maximum frequency of the PFD is limited by the speed of the circuitry that switches the latches to the state that allows detection of the next edges of the reference clock and the feedback signal.
Accordingly, it would be advantageous to have a circuit that increases the operating frequency of the phase-frequency detector.

Method for shaping a pulse width and circuit therefor


A self-distribution method for distributing information content among network connected devices of a communications network includes receiving a query having a code against a database from a wireless communications device, the code uniquely representing one of an advertising campaign, a product, or a service. The method also includes generating a result set by querying the database with the code, forwarding a link associated with the result set to a user-preferred remote location, the link being sent in an electronic message, wherein activation of the link directs a user to a first version of information content of the result set. A plurality of options to purchase user-preferred items from the first version of information content, the options including at least “purchase now” and “purchase later” features. A reminder message is forwarded to the wireless communications device if a user at the remote location selects the “purchase later” feature. The user is enabled to conduct a purchase transaction from at least the remote location or the wireless communications device. Systems for self-distributing information are also provided.

Transmission of data via communication devices, such as, for example, cellular phones, and communication networks such as Internet are generally known.
In recent days, users are constantly bombarded with marketing and advertising related information and the increased proliferation of direct marketing and spam have lead to increased discontent and distrust by consumers as to the benefit of marketing communications Recent studies show that many consumers would prefer to stop or block receiving such marketing and advertising related information and feel that such information has very little relevance for them. Part of the reason for such consumer attitude can be that dialogue between organizations and consumers has been primarily in one direction (e.g., from organizations to consumers). Consumers lack tools to better control and interact with marketing and advertisement messages presented to them. Also, the consumers are not presented with options to inquire, in real-time, about the information content they are interested in.
Moreover, organizations are also under increased pressure to clarify how marketing and advertising contribute to their profits to increase the bottom line. Tools that allow organizations to better monitor the impact of the marketing and advertising communications would be increasingly necessary.
Thus, a new tool that allows consumers to perform better management and control of the marketing and information laden environments that surround them while simultaneously providing the organizations an improved ability to monitor the effectiveness of their communications programs can lead to more effective communications with the consumers. Such tools can also improve the efficiency of the organizations and provide a better ability to quickly match the demands of the users with the industry supply.
Attempts to solve the above-noted problems have not been effective. Using presently available systems, it can be difficult for users to conveniently inquire about information regarding the content of a distributed media at a point of original contact (e.g., using a portable communications device in real-time). U.S. Pat. No. 6,490,432 to Wegener et al., U.S. Pat. No. 6,389,457 to Lazaridis et al. generally disclose various ways of forwarding information to users, the entire contents of such patents are incorporated by reference in this patent. Current use of communication devices can be restrictive due to the presence of long alphabetical strings representing data that is distributed over the communication networks. Furthermore, reading comprehensive text on small display screens, such as those on portable communication devices (e.g., cellular phones, PDAs, etc.) can be difficult.
Additionally, people under time constraints may not be well situated to read the information at an exact time when they desire the information. Further, the rich-media capability and interactivity typically available on personal computers is limited on portable communication devices, thereby limiting user experience. Also, there appears to be no system that allows consumers to personally store, manage, and manipulate their points of original contact with various forms of information in a user customized format that is accessible from any network-connected device.
Accordingly, systems and methods are needed to enable users to quickly inquire about information regarding the content of distributed media at the point of original contact while overcoming at least the above-noted problems. Systems and methods are also needed for organizations to directly and easily determine the effectiveness of their communication campaigns in real-time.

Self-distribution methods, coded self-distribution methods, and systems for distributing information


A brazing method connects an assembly made up of a pipe, a component provided with an opening, and a compensation element. The compensation element includes a support section and an insertion section that is arranged between an end of the pipe and the opening of the component. An inside diameter of the compensation element is smaller than a diameter of the opening in the component. The insertion section is inserted into the end of the pipe, and the support section is located between the pipe and the component and rests on the component at the edge of the opening. The compensation element, the pipe, and the component are heated, preferably inductively, in a region of the compensation element to a temperature above the melting temperature of brazing material that is present in the region of the brazing points.

Brazing and also soldering processes are well suited to connect two metallic components with each other. For the purposes of the following description and claims, brazing and soldering will be collectively referred to as brazing, but it should be understood that the present invention is intended to include both brazing and soldering processes. Unlike in welding processes, in brazing and soldering processes heat is supplied not to a closely limited surface area but, rather, either to the entire component when a furnace brazing method is made use of, or in the region of the brazing point when an induction brazing method is made use of. In this case, the induction of an electric current in the components to be connected generates heat in the component itself, which heats the component such that the brazing material arranged there will fuse.
There is the drawback, however, that for producing an optimum brazed joint, the gaps present between the two components to be connected must be very small. This makes the production of, more particularly, a T-joint complicated, in which a pipe end having an opening is connected in a second component.
It is the object of the present invention to simplify the production of a brazed joint such that with regard to the components to be brazed to one another, no close tolerances need to be adhered to.

Method of brazing, in particular induction brazing, and assembly

Faurecia Emissions Control Technologies, Germany GMBH


The fumaric acid salt of 2-{3-[4-(2-t-butyl-6-trifluoromethyl-4-pyrimidinyl)-1-piperazinyl]propylthio}-4-pyrimidinol is useful for treating disorders which respond to dopamine D3 ligands. It has higher stability at low pH and is therefore particularly suitable for oral administration in pharmaceutical compositions comprising this salt.

The invention relates to the fumaric acid salt of 2-{3-[4-(2-t-butyl-6-trifluoromethyl-4-pyrimidinyl)-1-piperazinyl]propylthio}-4-pyrimidinol and to a pharmaceutical composition comprising this compound. This compound has valuable therapeutic properties and is particularly useful for treating disorders which respond to dopamine D3 ligands.
WO 96/02519 describes said compound in the form of the free base of the formula
which is likewise useful for treating disorders which respond to dopamine D3 ligands. However, a salt of this compound is not disclosed.
It has now been found, surprisingly, that the acid addition salt of this compound with fumaric acid has particular advantages.
The present invention therefore relates to the fumaric acid salt of 2-{3-[4-(2-t-butyl-6-trifluoromethyl-4-pyrimidinyl)-1-piperazinyl]propylthio}-4-pyrimidinol and to a pharmaceutical composition comprising this compound.
The present invention also relates to tautomeric forms (pyridone structure) as well as solvates and hydrates of the fumaric acid salt.
The fumaric acid salt has very good affinity and high selectivity for the D3 receptor, i.e. it is a selective dopamine D3receptor ligand which acts regioselectively in the limbic system. It has a selectivity, Ki D2/Ki D3of 120 (cf. WO 96/02519). The compound is therefore useful for treating disorders which respond to dopamine D3ligands, eg. for treating disorders of the central nervous system, in particular schizophrenia, depressions, neuroses and psychoses. It is additionally useful for treating sleep disturbances and nausea and as antihistamine. Solubility tests of the substances showed a substantially higher solubility of the salt in water compared to that of the free base. Thus, resorption is significantly enhanced when the substance is administered orally and especially parenterally.
Furthermore, the fumarate is more soluble in polar solvents such as C1-C6-alkanols than the free base. Because of the altered solubility characteristics, it can also be purified more simply while avoiding physiologically unacceptable solvents. Additionally, the fumaric acid salt of 2-{3-[4-(2-t-butyl-6-trifluoromethyl-4-pyrimidinyl)-1-piperazinyl]propylthio}-4-pyrimidinol exhibits a higher stability against oxidative processes than 2-{3-[4-(2-t-butyl-6-trifluoromethyl-4-pyrimidinyl)-1-piperazinyl]propylthio}-4-pyrimidinol.
The free base can be prepared by the general processes described in WO 96/02519, preferably by process (ii). The fumarate is obtainable by reacting the free base with fumaric acid in a suitable solvent such as C1-C6-alkanols, in particular methanol, ethanol, n-propanol, isopropanol and n-butanol, a mixture of water and one of the said alcohols, or an ester such as ethyl acetate. An elevated temperature will generally be used so that the required fumarate crystallizes out on cooling and can be isolated in a straightforward manner. The fumaric acid is generally added in equimolar amounts or with a slight excess of up to about 10%. The fumarate produced in this way already has high purity. It can also be additionally purified by stirring in or recrystallization from a suitable solvent, e.g. water, one of the abovementioned alkanols, esters or mixtures thereof.
For treating the abovementioned disorders, the novel compound is administered orally or parenterally (subcutaneously, intravenously, intramuscularly, intraperitoneally) in a conventional way. Oral administration is preferred.
The dosage depends on the age, condition and weight of the patient and on the mode of administration. As a rule, the daily dose of active substance is about 10 to 1000 mg per patient and day on oral administration and about 1 to 500 mg per patient and day on parenteral administration.
The invention also relates to pharmaceutical compositions comprising the novel compound. These compositions are in the form of the usual solid or liquid pharmaceutical forms, for example as uncoated or (film-)coated tablets, capsules, powders, granules, suppositories, solutions or sprays. The active substances can for this purpose be processed with conventional pharmaceutical aids such as tablet binders, bulking agents, preservatives, tablet disintegrants, flow regulators, plasticizers, wetting agents, dispersants, emulsifiers, solvents, release-slowing agents, antioxidants and/or propellant gases (cf. H. Sucker et al., Pharmazeutische Technologie, Thieme-Verlag, Stuttgart, 1978). The administration forms obtained in this way normally contain from 1 to 99% by weight of active substance.

2-{3-[4-(2-t-butyl-6-trifluoromethyl-4-pyrimidinyl)-1- piperazinyl] propylthio}-4-pyrimidinol fumarate


A semiconductor body has a first surface, a second opposing surface, an edge, an active device region, and an edge termination region. A trench extends from the first surface into the semiconductor body in the edge termination region and includes sidewalls and an insulated electrode. A first conductivity type doped region extends from the first surface into the semiconductor body in the edge termination region and has a planar outer surface along the first surface that adjoins the trench at a corner of the trench sidewall and the first surface and has a side surface extending from the corner along the trench sidewall. A first interconnect contacts the trench electrode. A second interconnect contacts the outer surface and the side surface. A contact couples the first doped region to the trench electrode and has a bottom surface coplanar with the first surface from a contact edge to the corner.

Power semiconductor devices are commonly required to achieve a high reverse voltage blocking capability. Some applications require power semiconductor devices to withstand reverse voltages of 200 volts or greater.
Edge termination structures have been incorporated into power semiconductor devices to improve reverse voltage blocking capability. Edge termination structures typically surround the active device region that includes the power semiconductor devices, and may be near the edge of the substrate. Edge termination structures mitigate avalanche breakdown, and hence improve reverse voltage blocking capability, by redirecting equipotential lines within the drift region of the device toward the main surface and away from the edge of the substrate.
Edge termination structures may include trenches having buried electrodes that are electrically connected to a doped region adjacent the trench and at the surface of the substrate. This adjacent doped region forms a p-n junction with an oppositely doped subjacent region. Typically, the connection between the buried electrode and the adjacent doped region is provided by a contact that is formed over the buried electrode and in a recessed portion of the adjacent semiconductor substrate. A silicide layer or other conductive material may be provided in the recessed portion between the contact and the semiconductor to improve electrical connectivity. Because of the recess, the silicide layer is spaced close to the p-n junction. Subsequent thermal processing of the device, e.g. due to platinum diffusion for lifetime carrier reduction, inter-layer dielectric deposition, etc., causes the silicide layer to diffuse deeper into the semiconductor body toward the second doped region. If the silicide layer diffuses deep enough it will short the p-n junction between the first and second doped regions, causing substantial leakage. Devices with high leakage are discarded, reducing yield.

Method and contact structure for coupling a doped body region to a trench electrode of a semiconductor device


A UV curable composition useful for three-dimensional inkjet printing comprising (i) at least one UV curable urethane (meth)acrylate resin; (ii) at least one wax; (iii) at least one (meth)acrylate diluent; (iv) at least one photoinitiator; and (v) at least one polymerization inhibitor; wherein the amount of wax (ii) is sufficient to phase change the UV curable composition after jetting.

1. Field of the Invention
The present invention relates to selected ultra-violet light (UV) curable hot melt (or phase change) compositions that can be used either in a solid object printer such as a Thermojet printer to produce strong and desirable parts from CAD designs or in the adhesive industry to produce adhesive and their film coatings. In particular, this invention relates to UV curable phase change compositions which are comprised of (i) at least one UV curable urethane (meth)acrylate resin; (ii) at least one wax; (iii) at least one (meth)acrylate diluent; (iv) at least one photoinitiator; and (v) at least one polymerization inhibitor.
2. Brief Description of Art
Commercially available UV hot melt printers such as the 3D Thermojet solid object printer available from 3D Systems of Valencia, Calif., uses a phase change material or ink that is jetted through a print head as a liquid to form a wax-like thermopolymer part. These parts contain mixtures of various waxes and polymers and are solid at ambient temperatures, but convert to a liquid phase at elevated jetting temperatures. Accordingly, such phase change materials used in such printers are required to have a melting point of at least 65° C. and a viscosity of about 13 cPs at about 130° C. to about 140° C. (jetting temperature). Suitable waxes useful in these jettable phase change materials have included paraffin, microcrystalline waxes, polyethylene waxes, ester waxes and fatty amide waxes. Suitable polymers useful for these phase change materials have included polyurethane resins, tall oil rosin and rosin ester polymers.
Existing phase change materials have some problems associated either with their physical characteristics (e.g. they are weak and brittle and subject to cracking after being jetted) or have processing limitations (e.g. they must be jetted at relatively high temperatures (130-140° C.)) because of the high viscosities of the individual components of such materials. Accordingly, there is a need for better materials that overcome these problems. The present invention is believed to solve these problems.
This patent application is related to U.S. application Ser. No. 09/924,608 filed Aug. 6, 2001, which is a continuation of prior U.S. application Ser. No. 09/252,512, filed Feb. 18, 1999, now U.S. Pat. No. 6,270,335, which is a divisional of U.S. application Ser. No. 08/722,335, filed Sep. 27, 1996, now abandoned, which is a continuation-in-part of U.S. application Ser. No. 08/534,813, filed Sep. 27, 1995, now abandoned. This application also relates to U.S. Patent No. 6,193,923 (Ser. No. 09/252,512) which issued on Feb. 27, 2001 and is a divisional of Ser. No. 08/722,335. All of these related applications are incorporated by reference in their entirety herein

This patent is subject to a terminal disclaimer.

Ultra-violet light curable hot melt composition


Provided is a flash memory integrated circuit with a compression codec. The flash memory integrated circuit may simultaneously include a memory block and a compression codec circuit. The compression codec circuit may compress input data. A controller circuit may store the compressed input data in at least one page that is included in the memory block. Through this, it is possible to enhance a usage efficiency of a flash memory.

1. Field
One or more embodiments relate to a write operation or a read operation of a flash memory, and more particularly, to a technology associated with compressing input data of the flash memory and storing the compressed data.
2. Description of the Related Art
A flash memory may be a non-volatile memory that maintains stored data even when a power is not supplied. The flash memory may include a plurality of memory blocks. The flash memory may provide a function that can electrically erase and re-write data stored in the memory blocks.
Each of the memory blocks includes a plurality of cells. Here, the flash memory may have various types of cells such as NAND and NOR according to a physical structure of the cells. In particular, since a NAND flash memory may store a large capacity of data and may adopt a high density, there is great interest regarding NAND flash memory. Currently, the NAND flash memory is being widely used as a storage medium, and the like, for a portable device, for example, a mobile phone, a digital camera, an MP3 player, a camcorder, a personal digital assistant (PDA), and the like.
Each of the cells may be constructed to have a transistor. In a general flash memory, a threshold voltage of the transistor may be adjusted to program data or to read the data. In this instance, the cells may be classified into a single level cell (SLC) or a multi-level cell (MLC) according to a number of threshold voltages of the transistor.
The flash memory may need to be well designed in a situation where an area and a cost are limited. In particular, additional devices may be provided in the flash memory in order to reduce the size of data stored in the flash memory.

Flash memory integrated circuit with compression/decompression CODEC


Quality of Service (QoS) is provided to a secure data tunnel such an IPsec tunnel using information about the tunnel and the underlying data session to formulate a set of bandwidth requirements. A policy server operates to receive the information to create the set of bandwidth requirements which are enforced by a termination device. The termination device sets the bandwidths. QoS can be provided on a static or continuous basis. QoS can be provided on a dynamic basis. QoS can be provided at different levels depending on the type of data session. Multiple QoS can be provided for multiple data sessions existing simultaneously using multiple SSIDs.

Cellular and WiFi networks have sometimes been seen as competitors, primarily in the wireless data market. However, they may be viewed as complementary services or even as a way to enhance coverage. Coverage continues to be a key reason cellular customers complain and switch service providers. Recently, wireless usage has increased due to competitive pricing and new entrants within the telecommunications industry.
In the context of this specification, the term cellular is used to denote wireless networks and services associated with 1G, 2G, 2.5G, 3G, and 4G networks such as CDMA, TDMA, GSM, UMTS, and others. The term cellular is also used to distinguish one form of wireless networks from other wireless networks such as WiFi. WiFi denotes IEEE 802.11 wireless networks.
Service providers that offer wireless services have increased the number of minutes included in voice plans and encouraged customers to "cut the cord" by moving away from their local exchange carrier to an all-cellular service for their mobile and in-home voice services. Programs that entice customers with free long distance service and unlimited usage plans on weekends and after 7 p.m. have clearly driven in-home usage of cellular voice services.
At the same time of cellular service increases, there has been a rapid growth of WLAN (Wireless Local Area Network) deployments within enterprises, hotspots, and homes, along with improvements in VoIP over WLAN access to provide high-quality voice service. Now, combined with the introduction of dual-mode handsets (Combo Phones) that can support both cellular (GSM, UMTS or CDMA) and WLAN, new market opportunities for service providers are being created. The ability of service providers to deliver a comprehensive, high quality voice service that converges a mobile and fixed-line infrastructure is considered a compelling product differentiator.
One way in which to capitalize on the convergence of mobile and fixed-line infrastructures is to develop a strategy for combining CDMA and WiFi networks, or combining any cellular and WLAN networks. This strategy would leverage customers with existing broadband data access for backhaul and WiFi access networks primarily within residential homes and small businesses. Providing consumers with a nationwide, competitive, mobile service along with in-building quality that is on par with traditional wireline voice services opens a new market opportunity.
The offering of combining various wireless networks has led to the use of an industry-wide term, fixed mobile convergence (FMC). FMC is used to describe the combination of WiFi and Cellular into a mobile handset. Various manufacturers and service providers are developing a dual band mobile handset or endpoint device to provide combined WiFi and cellular services. In addition, some service providers are combining the WiFi/cellular services with cable broadband services.
The offering of combined WiFi/cellular services presents some problems. One of the problems is that although cellular networks are typically secure, WiFi and similar networks are typically not secure. The cellular networks have reliable encryption capabilities that allow telephone calls and other services to traverse the cellular network between two endpoint devices. In many cases, this encryption is proprietary and provides a secure network. On the contrary, WiFi networks tend to provide an open access with relatively little or no security. There are no assurances for privacy for a call traversing a WiFi network. In addition, a service provider has little or no control over a telephone call or data session after it leaves a cellular network and enters into a WiFi network.
The Data Over Cable Service Interface Specification (DOCSIS®) standard defines interface requirements for cable modems (CM) and eMTAs (multimedia terminal adapters with embedded CM) for the customer premise equipment used for high-speed data distribution over cable television system networks. The inability to provide a level of QoS within the DOCSIS access network is a limitation. Without QoS within the cable access network all traffic will have to contend with existing data traffic including FTP, streaming media, e-mail, gaming applications and other emerging Internet applications competing for their share of bandwidth. VOP services require strict levels of QoS in order to perform on par with circuit-switched voice services. Voice traffic has two critical required characteristics, very low delay and very low jitter. Please note that VOP can include such technologies as VoATM, VoIP, VoWLAN, to name a few.
Interactive voice conversations must have low delay. The maximum acceptable delay is about 150 ms from ear to ear. Unfortunately, there are limits on what can be done in the network to reduce delay, especially when VOP services compete with typical IP data services for network resources. Development of the packet cable standards has provided cable service providers, known as MSOs, the ability to deliver a superior VOP service which leverages QoS in the DOCSIS network.
DOCSIS networks are configured to deliver shared bandwidth to broadband cable customers and are over subscribed by MSOs to gain network efficiencies. Developing packet cable and packet cable multimedia (PCMM) standards which can provide dynamic QoS triggers to the DOCSIS network-based service flows (types of data traffic) is key to creating high quality latency and jitter sensitive applications like voice, multimedia and IP video.
As a result of the envisioned problems, a solution is needed that allows customers to access multiple wireless networks in a data session including cellular and WiFi while also providing security of the data session. The solution should provide security of the data session when it is initiated, terminated, or transited through open access networks such as WLAN and in particular WiFi. More specifically, the data session should receive quality of service (QoS) when traversing through the open access network in order to maintain specific qualities that are received in cellular or circuit-switched networks.

Ability to apply different levels of quality of service (QoS) to different sessions in an IPsec tunnel


A flowing junction reference electrode comprising a liquid junction member matched with a filter. The junction member and the filter are situated between a reference electrolyte solution and a sample solution. An array of nanochannels spans the junction member and provides fluid communication between the electrolyte solution and the sample solution. The filter is configured to allow a greater flux of electrolyte than that associated with the junction member. Preferably, the number of pores is greater than the number of nanochannels. The filter is preferably configured to have pores with an inner diameter that is the same or less than the inner diameter of the nanochannels. In some embodiment, the resistance of the filter is made lower relative to the resistance of the junction member by selecting suitable length, number, and inner diameter size for the pores of the filter relative to the nanochannels of the junction member.

1. Field of the Invention
The invention relates to potentiometric and electrochemical reference electrodes and, in particular, to composite liquid junction structures such as to be used in electrochemical reference electrodes for electrochemical measurements of solutions. The invention more particularly relates to reference electrodes for use where measurement or control of potential is desired such as with pH or ISE potentiometric sensors used for laboratory analysis, for on-line process monitoring, for field measurements, or in any application where the improved precision or extended useful life of the sensor is desirable. The invention also relates to, and may also be used, in non-potentiometric applications to be carried out at fixed potentials such as, for example, electrochemical machining and electro-organic synthesis.
2. Description of the Related Art
The invention is broadly concerned with reference electrodes, such as the reference electrode portion of combination electrodes, and the reference portion of all potentiometric devices that employ a reference electrode to provide the relatively stable reference potential required in various measurements such as electroanalytical measurements, controlled potential coulometry, polarography, and the like.
Potentiometric measurements are used widely for the determination of pH and the detection of other specific ions in a variety of settings, including chemical processes, environmental monitoring, health care and bio-processes. The accuracy of these measurements depends on the ability to measure the potential difference between a sensing electrode, whose potential varies with the analyte concentration in the measured sample solution, and a reference electrode, which ideally would maintain a constant potential. The physical interface between the reference electrode (typically the electrolyte of the reference electrode) and the sample solution is referred to as the liquid junction. The stability of the reference electrode, and consequently the accuracy of potentiometric measurements, are dependent on the constancy of the liquid junction and more particularly, the constancy of the potential across the liquid junction. However, the liquid junction and more particularly, the potential across the liquid junction are difficult to control and maintain at a constant level. Typically, it is the change in the liquid-junction potential that introduces error into the electrochemical measurement and results in the need for frequent sensor system calibration.
The errors observed in currently commercially available reference electrodes include transient or kinetic error, static error, and stirring error. Transient or kinetic error may arise from and typically refers to the relatively slow response between measurements, and slow ability to reach equilibrium, typically of five, ten, or fifteen minutes after exposure to extreme solutions. This delayed response is primarily caused by entrapment of sample solution within the physical junction. Transient error is typically a function of the time required to disperse this entrapped layer of sample solution and obtain a direct interface. The extent of this error is determined by the duration of prior immersion. Static errors may arise from and typically refer to persistent offset after equilibrium is reached. Large static errors are typically caused by irreversible entrapment of sample solution deep within the physical junction structure. Stirring error may arise from and typically refers to the shift in potential due to or associated with agitation of the sample solution. Stirring error is typically observed where there is a rate of agitation or flow of the sample. These errors exist in potentiometric electrode measurements of sample solutions, but tend to be suppressed in standard buffers where electrode accuracy is being checked. Therefore, users may see no reason to disbelieve the erroneous readings obtained in non-standard solutions. See D. P. Brezinski, "Kinetic, Static, and Stirring Errors of Liquid Junction Reference Electrodes", Analyst 108 (1983) 425-442; see also U.S. Pat. No. 4,495,052. These errors are large enough to be of practical consequence, and often correspond to relatively large difference in hydrogen ion (H+) concentration or activity. These errors, including those errors described above, tend to bias the measurements observed on pH meters by as much as 0.5 pH unit.
In typical, currently commercially available electroanalytical measurement systems, the interface between the reference electrode's electrolyte and the sample solution is the liquid junction. The junction potential at this sample-reference interface is related to a number of factors; it is an object of every reference electrode design to minimize the effect of the factors that would cause the liquid junction potential to drift or to vary in any way over time. Various materials have been utilized in forming a liquid junction, including porous ceramic rods, porous polymer disks, wood dowels, ground glass sleeves, capillary tubes, agar gels, asbestos fiber bundle, and other porous materials or devices, and the like. These junction structures are, in general, referred to as restriction devices because their function is to restrict the outward flow or diffusion of electrolyte from the reference electrode. However, one important factor that limits the useful lifetime of a reference electrode is that junction structures typically allow the sample solution to enter the junction structure. This transport of sample solution into the junction, whether by diffusion, migration, convection or other mechanism, results in the contamination of the junction structure and a resultant undesirable variation in the liquid junction potential. Such variation typically necessitates re-calibration of the electroanalytical measurement system. If this type of contamination of the junction continues over time, the junction structure may become fouled or clogged and develop even larger offset potentials and/or potentials that chronically drift despite repeated attempts at re-calibration. In addition, sample solution will often transport past the junction structure and reach the reference half-cell itself, potentially causing additional adverse reactions.
Currently commercially available reference electrodes, especially those used for potentiometric measurements, are typically constructed based on one of two distinct designs. Each of these designs is meant to address one principle limitation encountered when using reference electrodes for making potentiometric measurements. However, each of these designs fails to address a distinct principle limitation encountered when using reference electrodes for making potentiometric measurements.
One design category is often referred to as a flowing junction reference electrode. This design provides a stream of reference electrolyte flowing through a porous junction structure or member, in an attempt to provide a relatively uniform liquid junction potential. While this design is typically effective in providing a liquid junction potential that is more uniform over time than those of the alternate design, flowing junction reference electrodes typically require the use of large amounts of electrolyte over relatively short periods of time. Thus, currently commercially available flowing junction reference electrodes require frequent maintenance to replenish the supply of this electrolyte solution. Furthermore, while flowing junctions are often designed to minimize this use of electrolyte by restricting the volumetric flow of electrolyte, in such flowing junctions designs the flow velocity is often reduced to a velocity that is sufficiently low enough so that the sample solution enters the liquid junction structure, typically via mass transport (diffusion, migration, or convection). The presence of this sample solution in the junction structure causes variable junction potentials, loss of calibration, clogging of the junction structure, and, over time, failure of the reference electrode. See U.S. Pat. No. 5,360,529.
The alternative design category is referred to as a non-flowing, diffusion junction reference electrode. This design depends on the substantially constant diffusion of electrolyte solution through a minimally porous junction structure to provide a steady liquid junction potential. While this design is highly susceptible to mass transport of the sample stream into the porous structure, the resulting drift in liquid junction potential may be slow enough to be tolerable in certain industrial applications. While such electrodes require frequent re-calibration, they do not require replenishment of electrolyte to the extent that flowing liquid junction electrodes do. Furthermore, such electrodes do not require systems and associated equipment to feed the reference electrolyte to the electrode, as is the case for typical flowing liquid junction electrodes.
Both reference electrode designs are in wide use but, based on their respective limitations, are typically used in different areas of application. Where precision measurements are more often needed, the flowing liquid junction reference electrode is typically used. Thus the flowing junction design is most commonly used for laboratory reference electrodes and clinical analyzers. In the laboratory environment the reference electrolyte may be relatively easily refilled as needed, even on a relatively frequent basis. Where it is desirable to minimize maintenance and where precision may be sacrificed to certain degrees, the diffusion junction reference electrode is more often utilized. Thus the diffusion junction reference electrode is typically used in industrial potentiometric sensor designs. An industrial sensor that uses a non-flowing, diffusion junction reference will typically require re-calibration on a more regular basis because of the relatively large amount of transport of the sample stream into the liquid junction structure. It is therefore not unusual for the industrial operator to install a new sensor every three months instead of attempting to re-calibrate the old sensor. For this reason, the industrial pH sensor with a built-in diffusion reference electrode is now a disposable item in most industrial applications.
In summary, two principal problems with currently commercially available reference electrodes are the frequent maintenance requirement of the flowing junction design electrodes and the frequent re-calibration requirements of the diffusion junction design electrodes. More specifically, nearly all flowing junction designs consume large amounts of electrolyte and this electrolyte needs to be replenished on a regular basis. While there are a few flowing junction designs that require small amounts of electrolyte, these designs have achieved this by greatly reducing the electrolyte flow to the point that the sample solution flows into the liquid junction structure. A slow flowing junction reference electrode performs little better than a non-flowing, diffusion junction reference electrode. On the other hand, the non-flowing, diffusion junction electrode requires no electrolyte replenishment but will be subject to slow drift errors due to transport of the sample stream into the liquid junction structure. This drift typically prevents such reference electrodes from being used for precision measurements. Frequently, such transport will cause an irreversible instability to develop in the reference electrode that will render it incapable of being re-calibrated. Because of these inherent shortcomings, sensors employing such reference electrodes are often designed to be thrown away and replaced instead of re-calibrated. As a group, all non-flowing, diffusion junction reference electrodes have a very short operational life measured in weeks and months and in the best of circumstances seldom over one to two years.
Accordingly, there is a need in the art for an electrode design that exhibits both the relatively stable potential of currently commercially available flowing junction designs and the relative lack of the need to replenish reference electrolyte solution as found in currently commercially available non-flowing junction designs. Such a needed design would exhibit a relative stable junction potential over prolonged periods of time, while not exhibiting the various limitations and drawbacks of currently commercially available flowing junction and non-flowing designs.

Reference electrode having a flowing liquid junction and filter members


An instrument and method for measuring the elemental composition of a test material. The instrument has a source of penetrating radiation for irradiating an irradiated region of the test material, a detector for detecting fluorescence emission by the test material and for generating a detector signal, and a controller for converting the detector signal into a spectrum characterizing the composition of the test material. A platen of attenuating material extends outward from adjacent to, and surrounding, the irradiated surface of the test material. In certain embodiments, the thickness of the attenuating platen is tapered such as to decrease with increasing radial distance from the central irradiated region of the test material.

X-ray fluorescence (XRF) instruments measure properties of material by irradiating the material with x-rays or gamma rays and analyzing the fluorescent radiation to determine specified properties. The term "x-rays", as used herein and in any appended claims, refers to radiation that is generated either by radioactive sources, or by instruments such as x-ray tubes, and encompasses within the term all forms of penetrating radiation including gamma rays. The specified properties to be determined may include the elemental composition of the irradiated object, or the distribution of a particular element in the near surface of the object, or the density of the object, or the morphology.
XRF instruments typically have collimated beams and appropriate shielding so that the operator is not subjected to undue ionizing radiation. For example, laboratory XRF instruments typically require the operator to completely cover the instrument and the sample so that negligible radiation emanates from the XRF instrument.
Portable XRF instruments have special radiation shielding requirements since their use typically requires that the operator hold the instrument while making the measurements. The ambient radiation levels are a primary concern. The operator and any nearby people must not be subject to undue levels of ionizing radiation. XRF instruments that inspect houses for lead paint are one specific embodiment of this invention and offer a good example of its need.
Portable XRF instruments are now the choice for quantitative determinations of the concentration of lead in painted walls of a house. Commercial portable XRF lead-paint instruments use either radioactive sources, such as 109Cd and 57Co, or x-ray tubes, to generate the fluorescing radiation that excite the lead atoms in the painted surfaces. The intensity of the fluoresced characteristic x-rays of lead gives measure to its concentration and allows the inspector to determine whether the paint is out of compliance with established regulatory limits.
The allowable ambient radiation levels differ from country to country. The United States regulations place restrictions on the radiation levels in the ambient space directly behind the instrument's x-ray exit port. Of special concern is the space where the operator may have his hands or face. Minimal attention is paid to the radiation levels in the space between the wall being inspected and the surfaces of the operator's hands, arms and body when taking the measurements. The radiation limitations in the US can be satisfied by applying shielding in the instrument itself.
Radiation limitations in Europe are currently significantly more stringent than those in the United States. The acceptable level of radiation for an occupation worker is ten times lower; that is, 1 μSv/hr for Europe and 10 μSv/hr for the US. (μSv/hr is the standard abbreviation for microSievert per hour, a level of radiation equivalent to 100 microrem of radiation in now obsolete units.) Moreover, and of special importance to this invention, France requires that no point 10 cm from any accessible surface of the XRF instrument exceed the 1 μSv/hr level. That requirement cannot be satisfied with the shielding inside an XRF instrument.
Commercial hand-held x-ray fluorescing instruments have radiation absorbing material in the nose of the instrument. This absorbing material is designed to absorb radiation that comes directly from the source but is not going out through the exit port to strike the sample under study. This absorbing material also absorbs radiation that has been once-scattered so that the once-scattered radiation does not enter the detector and does not confound the measurement being made. The absorbing material in the nose of the inspection instrument, however, cannot prevent radiation that is multiply scattered such that it emerges from the target in a place and direction in such a way as to not intersect the nose of the instrument.

Portable X-ray fluorescence instrument with tapered absorption collar