According to one embodiment, a radio device includes: a mounting board having a conductive plane; a semiconductor package mounted on the mounting board and having a interposer having a conductive plane, a semiconductor chip mounted on one surface of the interposer, and an antenna having a conductive element formed on the one surface and connected to the semiconductor chip; and a plurality of connection portions connecting the mounting board and the interposer. A first electrical length of the first connection portion which is nearest the conductive element among the plurality of connection portions or a second electrical length of the first connection portion including a conductive plane of the mounting board or interposer connected to the first connection portion is less than ½ wavelength of the operating frequency of the antenna.

There is known a technique in which an antenna is incorporated in a semiconductor package in which a radio circuit is mounted in order to achieve a size reduction of a radio device. For example, among semiconductor packages in which an antenna is mounted in an interposer so as to incorporate an antenna, there is one in which a conductive material does not exist in at least 50% of the antenna mounting area of the interposer. With the configuration in which a conductive material is not provided near the antenna, degradation in antenna characteristics can be suppressed.
In the case where a semiconductor package is mounted in a radio device, an integrated circuit package is mounted on a mounting board. Like the interposer, the mounting board includes conductive materials such as wiring and ground. As a method for connecting the mounting board and semiconductor package, there is known a BGA (mall grid array) method that connects them using a solder ball.
Even in the case where a configuration in which the conductive material is absent only in a part of the interposer is adopted, when a semiconductor package is mounted on the radio device, conductive materials such as wiring and solder balls are inevitably arranged near the antenna, which may result in degradation in the antenna characteristics.


A method of automated parking assistance. A logic unit reads identification information from a transponder attached to a vehicle and determines the current position of the vehicle by measuring distances between the transponder and multiple stationary sensor devices. A pre-defined parking location is stored by pressing a single button. If the current position of the vehicle is not equal to the pre-defined parking location when the vehicle subsequently approaches, the logic unit determines one or more directions in which the current position of the vehicle must be adjusted to reduce the distance between the current position of the vehicle and the pre-defined parking location. A display device displays one or more guidance signals corresponding to the one or more directions in which the current position of the vehicle must be adjusted. If the current position of the vehicle is equal to the pre-defined parking location, a stop signal is displayed.

1. Technical Field
The present invention relates in general to automobiles and in particular to garages. Still more particularly, the present invention relates to an improved method and apparatus for automated parking assistance.
2. Description of the Related Art
In order to safely maneuver a vehicle within a limited area, such as a garage, a driver must simultaneously be aware of the dynamic distances between the driver's vehicle and other vehicles, walls, and/or objects. If a vehicle is parked too close to a side wall (i.e., a wall to the left or right of the vehicle) within a garage, damage may be incurred by the vehicle and/or the wall when the driver subsequently exits the vehicle. Similarly, if a vehicle is parked too close to the back wall (i.e., the wall opposite the garage door) of a garage, damage may be incurred by the vehicle and/or the garage door if the vehicle protrudes from the opening of the garage when the garage door is closed. If a first vehicle is parked too far away from a side wall within a garage, the first vehicle may obstruct the entry of a second vehicle into the garage.
Garages are typically utilized to park one or more vehicles in the same parking spaces over a period of time (e.g., a family that regularly parks the same two cars in the same spots). In such a garage, each vehicle may have different dimensions and thus occupy less space relative to other objects and/or vehicles when the vehicle is parked in a preferred pre-defined location within the garage. A driver who is distracted or unfamiliar with the garage may attempt to park the vehicle in a position other than the pre-defined location, thereby jeopardizing the vehicle, the walls of the garage, the garage door, and/or an adjacent parking space.

Method and apparatus for automated parking assistance


Systems and methods are presented to dynamically generate multiple hierarchies of inter-object relationships based on object attribute values. In one aspect, a data structure includes a first virtual object data field to represent a first object of multiple objects in a data store. A second virtual object data field represents a second object of the multiple objects. Attributes of the first object intersect with attributes of the second object to form multiple hierarchies of inter-object relationships.

Any object can be linked, correlated, associated, differentiated, or in some manner categorized with respect to a different object to form implicit or explicit inter-object relationships. For instance, in an organization, a person typically has implicit and explicit relationships with other people in the organization, organizational resources (e.g., printers, facilities, etc.), geographical locations, business units, club memberships, and so on. Each implicit and/or explicit relationship between respective objects (i.e., the person, the other people, a resource, etc.) represents a respective hierarchical data relationship.
For example, one hierarchical data relationship is represented by each person within the company that has access to a specific resource (e.g., a building on the company campus, a room, a printer, etc); the resource being the root node of the hierarchy and the individuals with access to the resource being the leaves. Another hierarchical data relationship is represented by individuals that make up the management structure of the company. Other inter-object data relationships may represent a hierarchy of individuals within a particular business unit, all employees of the company that have specialized training, and so on.
Unfortunately, even though a data store can be configured to some extent by a network administrator to represent inter-object relationships within hierarchies of other data, complex inter-object relationships (e.g., such as those representing a single object within more that one hierarchy) are not simply and adequately represented using conventional data store (e.g., directory, database, etc.) systems and technologies. (Traditional directories include those based on the well-known X.500 standard and the Lightweight Directory Access Protocol (LDAP).
To illustrate this limitation of traditional data store systems and technologies, consider that a directory typically represents inter-object relationships using rigid data naming and inflexible directory schemas. Objects or nodes in the directory are organized within a single hierarchy with a root node at the top of the hierarchy. The root node has a name. Each other node in the directory is named based on its direct naming relationship to the root node and also with respect to each intervening node in the respective node's hierarchy. As a result, if a parent object is renamed in a single operation, any objects that are subordinate or children of the parent object are also renamed in that same single operation. This is because an object's full "distinguished name" includes the name of each parent object(s) all the way down the line to the root node's name.
It is the full distinguished name of an object that also represents its static location or data relationship with respect to each other object in the data store. Thus, an object's distinguished name inflexibly inter-tangles object naming within a single hierarchy with inter-object relationships in that hierarchy. Because of this, any navigation of the data store must be performed from top-to-bottom to determine and subsequently present any inter-object relationships—that is from the root object, to a parent object to any subordinate child object(s).
Because traditional data stores (e.g., directories, databases, and so on) rely on a carefully specified and inflexible object naming scheme to identify inter-object relationships, an administrator configuring the data store requires a-priori knowledge of the inter-object relationships when configuring the data store. Additionally, any configuration of the data store must consider not only the proper representation of inter-object relationships in the data store, but must also consider the heuristics that a search engine requires to navigate the data store.
To make matters worse, elastic data relationships are not easily described, represented, or navigated using conventional data store systems and techniques. An elastic data relationship is one wherein the relationship is derived from data that defines an object at any point in time. This means that over time elastic data relationships can be dynamic. For instance, consider the following non-obvious and potentially elastic data relationships: a Web site and the Web pages that make up the Web site, a customer and the individuated services that the customer purchases from a merchant, a personal computer (PC) and peripheral devices that are coupled to the PC, a city and the districts within the city, a business and the business' contacts, an employee and the employee's dependents, and the like.
These non-obvious and potentially elastic data relationships are not easily represented because whenever a one-to-one correspondence between a surface object and corresponding sub-objects needs to be represented in the data store, an irreversible design choice must be made. (Conventional practice is to strictly control directory schema updates due to the serious nature of directory schema modification). A network administrator can opt for "total incorporation" of the sub-objects into the particular object by representing the sub-objects as attributes of the surface object in the directory schema. Or the network administrator can opt for "total distinction" of each object, by creating separate objects in the schema for sub-object components, and positioning the separate objects subordinate to the surface object.
To illustrate this irreversible design choice, consider that a particular network router includes multiple router modules plugged into the router's backplane. Information about the router and the router modules are typically stored in a directory in one or two different fashions—each of which may be equally unsatisfactory depending on how entities and their respective relationships to other entities are represented. One design choice is to characterize a router and its corresponding router modules as a single hierarchical data structure representing the network router as a parent object, and the corresponding router modules as child objects that are subordinate to the parent object. A different design choice is to characterize the router and the router's associated router modules as a single parent object with complex attributes. The parent object represents the router (backplane), and the complex attributes represent the respective router modules that are hosted by the router.
In consideration of the first design choice, depending how the router and the modules are configured, collapsing information about the router modules, or boards onto the backplane may prove unwieldy. This is because the functionality of the router's backplane may be small as compared to the functionality of the network router modules hosted by the router. Whereas considering the second design choice, completely separating the boards from the backplane may be equally unsatisfactory because the router is still a single physical router box that generally includes a number of router modules.
Both of the described solutions to representing data relationships with an inflexible directory schema are time consuming to implement and counter-intuitive. The semantics of shape and naming in the directory must be agreed on in advance to solve the simplest design problem. Thus, whenever a one-to-one correspondence between an entity and corresponding sub-entities needs to be represented in a traditional directory, an irreversible and inflexible design choice must be made within the directory schema.
Whichever design choice is selected, the data store and tools used to navigate, search and present objects within the data store with respect to inter-object relationships have been substantially limited. This is because the data store itself can not represent all of the possible implicit and explicit inter-object relationships of an object. This is considered by many computer programmers to be one of the most intractable problems of directory schema in traditional directories. This is also deemed to be the reason that computer program applications are not typically portable across directory platforms or even directory instances.
To further worsen matters, recent developments in information technology provide network administrators with opportunities to tie disparate data stores (e.g., databases, directories, and so on) of data together into a single logical directory or "metadirectory". Such disparate databases and directories include, for example, information corresponding to enterprise users, tangible and intangible resources, financial information, corporate e-mail systems, network operating systems, and so on.
Metadirectories present network administrators with complex and often elastic object data relationships that cannot be simply or adequately described, represented, navigated, or presented using traditional systems and procedures to configure and manage data stores. Considerable efforts are required on the part of the administrator (or a staff of administrators) to configure a data store. Manually determining and implementing such inter-object relationships (whether they be dynamic or not) is fraught with the potential for human error and oversight. Furthermore, database administrators with an appropriate level of such knowledge to perform such a directory configuration are expensive.
The following described subject matter addresses these and other problems of representing inter-object relationships.

Dynamically generating multiple hierarchies of inter-object relationships based on object attribute values


A polyphase sequentially joined-segment coil of a rotary electric machine and a production method thereof are provided. The coil is made up of a plurality of conductor segments joined in series. Each of the conductor segments a head projecting from a stator core, a pair of legs, and a pair of ends projecting from the stator core. The heads are of two types: a large-sized head and a small-sized head extending inside the large-sized head. This structure permits the length of the conductor segments in an axial direction of the core to be decreased and improves cooling capability of the machine and coil losses.

1. Technical Field of the Invention
The present invention relates generally to a sequentially joined-segment coil of a rotary electric machine and a production method thereof.
2. Background Art
Sequentially joined-segment stator coils have been proposed which are made by sequentially join ends of conductor segments inserted in slots in a stator core. For instance, Japanese Patent Nos. 3118837 and 3196738, assigned to the same assignee as that of this application, disclose a production method of joining U-shaped conductor segments in sequence to make a stator coil.
The sequentially joined segment stator coil, as taught in the above patents, is made by inserting a pair of legs of each conductor segment into two of slots of a core located at an interval away from each other which is substantially equivalent to a magnetic pole pitch of a rotor, bending end portions of the legs projecting from the slots in a circumferential direction of the core, and joining the end portions of the conductor segments in series.
The conductor segments each consist of a U or V-shaped head (also called a turn), a pair of side conductor portions extending from the head to be inserted into two of the slots of the core from an axial direction of the core, and end portions which project from the side conductor portions toward the other side of the slots and extend in the circumferential direction of the core. The projecting end portions are joined in pair. In the following discussion, the side conductor portion and the projecting end portion will also be referred to as a leg as a whole, the heads of the conductor segments will also be referred to as a segment head-side coil end of the stator coil, and the projecting end portions will also be referred to as a segment end-side coil end of the stator coil.
Japanese Patent Publication No. 2000-92766 discloses a sequentially joined-segment stator coil in which six side conductor portions of conductor segments are aligned in a radius direction of the core and inserted into one of the slots of the core. In the segment head-side coil end, the head leading to an innermost one (i.e., the first one) of the six side conductor portions inserted into one of the slots and an outermost one of the six side conductor portions inserted into another slot are the largest outer heads, the head leading to the second and fifth ones of the side conductor portions extending inside the first and sixth ones forms a central head, and the head leading to innermost two (i.e., the third and fourth ones) of the side conductor portions extending inside the second and fifth ones forms an inner head.
The above sequentially joined-segment stator coil is produced in the following steps. First, a required number of pine needle-like conductor segments are prepared. Each of the conductor segments is formed into a U-shape one with side conductor portions extending at a magnetic pole pitch interval away from each other. The side conductor portions of each conductor segment are placed in alignment with two of the slots formed in the core, respectively, (i.e., in a circumferential direction of the core) for simultaneous insertion of the side conductor portions into the slots. These steps may be achieved with a pair of coaxially arrayed rings with slots, as illustrated in FIG. 3 of Japanese Patent No. 3118837. Specifically, legs of each conductor segment are fitted in two of the slots aligned in a radius direction of the rings. Next, the rings are turned relative to each other through a given angle equivalent to a magnetic pole pitch to spread the legs, thereby forming the U-shaped conductor segment. Subsequently, the head of each of the U-shaped conductor segments is held. The legs are drawn from the slots and then inserted into the slots of the core.
Next, end portions of the legs projecting from the slots are bent in the circumferential direction of the core by half a magnetic pole pitch. Such bending may be achieved with a plurality of coaxially arrayed rings with slots, as illustrated in FIGS. 4 and 5 of Japanese Patent No. 03196738. Specifically, tips of the projecting end portions of the legs are inserted into the slots of the rings. The rings are rotated in the circumferential direction by half a magnetic pole pitch (i.e., an electrical angle of π/2) to bent the projecting end portions in the circumferential direction through half the magnetic pole pitch. It is advisable that the rotation of the rings be performed while urging the rings toward the projecting end portions (i.e., the axial direction of the core) for increasing the radius of curvature of the turn of each conductor segment. Next, the projecting end portions are welded in a given sequence, thereby forming an endless phase coil. Any one of the heads of the U-shaped conductor segments is cut to define coil terminals. If the coil terminals are made longer and bent in the circumferential direction, they may be employed as a neutral point connecting line. The reason that the coil terminals are provided in the segment head-side coil end is because if the coil terminals are provided in the segment end-side coil end, they will interface with welding of the end portions of the conductor segments.
The above sequentially joined-segment stator coil, however, encounters the drawback in that the three heads or turns of the conductor segments disposed in each slot of the core are laid to overlap each other in the axial direction (i.e., a thickness-wise direction) of the core, thus resulting in an increase in length of the coil end (i.e., the projecting end portions of the conductor segments), which leads to an increased total length of a rotary electric machine.
Additionally, the largest outer heads of the conductor segments lead to the outermost side conductor portions and the innermost side conductor portions in the slots, thus requiring a longer length of the segment head-side coil end, which results in increases in coil resistance leading to a coil loss and in ventilating resistance of the coil ends leading to a reduction in cooling capability.

Sequentially joined-segment coil for rotary electrical machine


A metallurgical vessel cover having integral fume collection provisions is disclosed. The cover features a plurality of inlet openings defined about the perimeter of the cover that direct fumes or other gases residing around the exterior of the cover, through the interior of the cover, and to a single collection region. There, the fumes or gases are discharged through a shroud, which preferably is connected to an attachable venting duct. The cover also features an internal configuration for reducing heat transfer through the cover.

1. Field of the Invention
The present invention relates to a ladle cover for a metallurgical vessel. The cover has provisions for collecting fumes and vapors from the upper periphery of the vessel. The present invention finds particular application in the production and/or processing of leaded steel during which hazardous lead-containing fumes are typically emitted.
2. Description of Related Art
It is often desirable to access the contents of a covered metallurgical vessel, such as to introduce alloying elements, air, or other gases. Accordingly, prior artisans have provided covers with openings to accommodate such passage of materials. Collin illustrated a ladle cover having an upwardly extending member for the passage of air, and an opening for receiving and discharging metal in U.S. Pat. No. 429,337. Other aspects of modern vessel cover construction include a lightweight ladle lid design such as disclosed by Heyer et al. in U.S. Pat. No. 4,834,346. Lift brackets have also been provided for such covers, as illustrated by Reighart in U.S. Pat. No. 2,774,123.
During the production of particular alloyed metals, such as for example, leaded steel, hazardous fumes or vapors are often emitted from various components used in the production process. Efforts have been taken to collect such harmful fumes, such as described in U.S. Pat. No. 4,724,895 to Mulesa. Mulesa and other artisans have directed efforts to collecting fumes emitted during and after casting. That is, the prior art has primarily focused on collecting fumes emitted from components during and after casting molten material, such as leaded steel.
A significant amount of harmful, or potentially harmful, fumes may still escape from a metallurgical process prior to casting, even a process utilizing state of the art fume collection equipment. Accordingly, there is a need for a technique and associated hardware by which potentially harmful fumes, or at least a significant proportion of such fumes, may be collected from process components containing the molten metal prior to casting. More particularly, there is a need for a technique and related equipment for collecting hazardous fumes emitted from a metallurgical vessel, such as a ladle.
In addition to the foregoing, another concern in the design of a cover for a metallurgical vessel is minimizing heat loss through the cover. This is particularly significant for applications in which the vessel is a ladle utilized to receive molten metal. Prior artisans have incorporated heat resistant refractory materials along the underside of covers such as disclosed in U.S. Pat. No. 2,122,032 to Goldberg et al. Although satisfactory in most respects, it would be desirable to provide a vessel cover having improved heat retention qualities, i.e. relatively low rates of heat transfer through the cover.


Embodiments provide mechanisms and methods for providing disconnectible applications capable of executing at least semi-autonomously, i.e., without needing constant contact with a server, on a client substantially independent of server connectivity. The ability of a disconnectible application to execute on a client substantially independent of server connectivity can enable enhanced flexibility in organizing applications to build data processing systems.

Since its inception in 1995, the Java™ programming language has become increasingly popular. (Java™ is a trademark of Sun Microsystems, Inc.) Java, which is an interpreted language, enabled the creation of applications which could be run on a wide variety of platforms. This ability to function across a variety of different client platforms, i.e., platform independence, and Java's relatively easy implementation of network applications has resulted in the use of Java, as well as other programming languages that provide platform independence, in endeavors as basic as personal web pages to endeavors as complex as large business-to-business enterprise systems.
However, since applications that are designed to provide functionality over networked systems are necessarily designed to rely upon frequent connectivity in order for the applications to function, such applications are often rendered useless when connectivity is unreliable. For example, many applications require frequent interactive transmission with a remote server. Such applications often wait for replies and confirmations for any transmissions before proceeding to a next step. Additionally, since such conventional applications cannot function without server/client connectivity, servers are often forced to devote resources to relatively unimportant responses to remote clients, without which the remote applications would be held up.
What is needed is an improved mechanism for managing server/client interaction.


A system for providing open session based selective broadcasting in an instant messaging system. The instant messaging system user is provided with a mechanism through which they can broadcast a user-defined message to the participants in all currently open instant messaging sessions with the user, or to the participants in a selected subset of currently open instant messaging sessions with the user. The system provides the ability to capture and save a list of the participants receiving a previously broadcast message. The captured participant list can be subsequently recalled and used to broadcast another user defined message when the interruption ends, and the user can resume participation in the sessions.

As it is generally known, in computer-based communications, instant messaging systems enable instant communications between two or more people over a communication network such as the Internet. Instant messaging typically requires the use of a client program or logic to provide an instant messaging service. Instant messaging differs from electronic mail ("email") in that conversations happen in real-time. Instant messaging sessions are sometimes referred to as "chat" sessions. Distribution of on-line "presence" information describing current user states, e.g. whether users are currently on-line and available to participate in an instant messaging session, is a key aspect of existing instant messaging systems. The combination of current user state distribution and the capability to hold real-time, on-line conversations continues to make instant messaging a very useful tool for vital business communications. Examples of existing instant messaging technologies include Qnext, MSN Messenger, AOL Instant Messenger, Yahoo! Messenger, Skype, Google Talk, .NET Messenger Service, Jabber, QQ, iChat and ICQ, and Internet Relay Chat (IRC).
With the increased use of instant messaging, a problem arises when users find themselves multitasking between multiple instant messaging sessions, and are then interrupted by an external event that must be dealt with, such as a phone ringing, a manager stopping in their office, etc. In such a situation, the user needs to be able to quickly and efficiently inform all of the other users they are currently instant messaging with in the multiple instant messaging session that they are being temporarily interrupted. Similarly, the user needs to be able to inform all of those other users when the interruption is over, and they can resume the instant messaging sessions (e.g. the phone call is over, the manager leaves their office, etc.).
This problem has not previously been recognized, and existing system design accordingly does not address it. In existing systems, in order for a user to communicate a message to all participants in all current instant messaging sessions in which they are participating, the user must either type or otherwise enter a separate message into each of the individual sessions (e.g. type "be right back—phone rang!" into the text entry field for each session), or copy and paste such a message into each of the session text entry fields. These operations are time consuming and inconvenient, and as a result users typically just tend to the interruption without information the other session participants, potentially resulting in confusion or misunderstanding as to why their responses may be delayed during the interruption.
Some existing systems allow users to broadcast a message to a separately defined user community, or to all users logged-in at the time the broadcast is sent. Such approaches are not useful with regard to solving the above described problem, since the messages conveyed through them are delivered to a set of recipients different from those who need to be reached (i.e. current participants in multiple open instant messaging sessions of a user that has been interrupted). Accordingly, the recipient set in these existing systems is not responsive to the dynamically changing set of participants for the currently open instant messaging sessions of a given user. Moreover, access to broadcasting features of existing systems is often limited to users having special privileges (e.g. administrator users or the like), and they are not available to ordinary individual users of the instant messaging system. Moreover, existing systems fail to foresee any need to capture a list of participants from multiple instant messaging sessions to which a previous message has been sent (e.g. "sorry—I have to answer the phone. I'll be right back!"), so that a subsequent message can be sent to that same set of users at the end of the interruption (e.g. "OK—I'm back now.").
For the above reasons and others, it would be desirable to have a new system that allows an instant messaging system user to quickly and conveniently communicate with other participants in multiple current instant messaging sessions at the time of an interruption, and to capture the list of participants to which a previous message was sent so that a subsequent message can be sent to those same users when the interruption is over.

Providing open session based selective broadcasting in an instant messaging system

International Business Machines Corporation


A method is provided to select circuit cells for use in optimization of an integrated circuit design from among a plurality of circuit cells within a cell library, the method comprising: obtaining a value for each cell of the plurality that is indicative of both the cell's power dissipation and the cell's rate of output voltage change; ordering the cells of the plurality based upon the values; identifying a difference between values of cells that are proximate each other within the ordering of the cells that meets a threshold; and designating a cut point within the ordering of the cells based upon the identified difference.

1. Field of the Invention
The invention relates to the design of electronic circuits and more particularly to optimized mapping of cells having different threshold voltages to an integrated circuit design.
2. Description of the Related Art
Synthesis of an integrated circuit design involves a process of translation of a behavioral description of the design to a structural description of the design optimized according to one or more constraints such as timing, power dissipation, area or testability. A designer ordinarily sets forth a behavioral description of a design in a high level descriptive language (HDL) such as Verilog or VHDL, or describes a model of the design in the C or C++ programming language, for example. Ordinarily, an HDL description describes a register transfer level (RTL) model of a design in terms of data flow between registers that store information between clock cycles in a circuit.
In an RTL description storage devices (i.e., registers) store current circuit state information, and a set of logical equations define the next state of the circuit. The next circuit state is stored in the storage devices in response to a clock signal defined for the circuit. The clock signal defines the interval of time in which the next state is to be computed, and is used by the storage devices to determine when to sample an input to the storage device. An input value thus sampled is stored in the storage device until the subsequent sampling point occurs upon the occurrence of a later clock signal.
During synthesis, an RTL behavioral description of a circuit design is converted into a netlist, which is a list of electronic logic cells with a description of the interconnections between inputs and outputs of the various cell instances. The cells of the netlist are used to implement the logical next state equations of the RTL description. The cells in the netlist are obtained from of a cell library. A cell represents a circuit element that is available in a particular implementation technology. A cell library may comprise a few hundred cells corresponding to primitive function circuits, such as inverters, NAND gates, NOR gates and possibly to more complex Boolean function circuits and perhaps, to sequential elements like latches and flip-flops.
A cell may itself be defined in terms of a netlist that includes a cell model that specifies logical, electrical, and physical attributes and that may include one or more primitives circuits. One typical cell attribute is its logical function (e.g., AND, OR, NAND, NOR, INVERT, etc., or a complex logical function implementing an equation of basic combinational or sequential functions). Other cell attributes provide information concerning a variety of the cell's characteristics such as timing, area, power dissipation, testability and threshold voltage (Vt), for example.
During synthesis, cells are mapped from the cell library to a netlist generated from the RTL description. A typical cell library may include multiple cells that have the same basic function attribute but differ in one or more other attributes. For example, a cell library may include multiple different cells that perform a two-input NAND logic function, but each such functionally equivalent cell may employ transistors having different threshold voltages (Vt).
Synthesis uses constraint-driven optimization techniques to select from among multiple cells with similar functionalities when mapping cells to netlist locations. Optimized mapping based upon cell threshold voltage has become increasingly important since the impact of leakage power upon performance increases as the physical dimensions of circuit become smaller. In general, a lower Vt transistor can switch (i.e., change states) more rapidly than a higher Vt transistor. A lower Vt transistor typically has a larger leakage current than a higher Vt transistor. As a result, a lower Vt transistor ordinarily dissipates more power than a higher Vt transistor. Thus, there often is an inherent trade-off between power dissipation and switching speed when selecting between cells having different threshold voltages.
In particular, transistor sub-threshold leakage current grows exponentially and becomes an increasingly large component of total power dissipation with scaling down of technology. For instance, the drain current of a MOSFET in the sub-threshold region can be expressed as (assuming Vds [drain to source voltage] is large compared to the thermal voltage)(1) Ithreshold=I0+10((Vgs-Vt)/S)  (1)where, I0 is the drain current with Vgs [gate to source voltage]=Vt [threshold voltage] and S is the sub-threshold slope. It will be appreciated that even a small decrease in Vt can result in an order of magnitude increase in the sub-threshold leakage current.
Consequently, multiple-Vt optimization aimed at leakage power optimization has become an important phase of synthesis. During a multiple-Vt optimization phase, cells are mapped to netlist locations based at least in part upon threshold voltage constraints. Typically, lower Vt cells are selected for timing critical circuit paths, and higher Vt cells are selected for non-critical timing paths to reduce leakage current.
Unfortunately, there have been shortcomings with prior multiple Vt optimization techniques. Past approaches to multiple-Vt optimization often involved name-based cell identification that placed a heavy reliance on library cell names to identify cells having similar functionality but different threshold voltages. In other words, these prior techniques often relied upon a library vendor having named cells with sufficient clarity to discern cells having different threshold voltages but the same functionality. For example, in order to satisfy timing constraints, an optimization process might seek to replace a high Vt cell with a functionally equivalent low Vt cell. Under an earlier approach, identification of the corresponding low Vt cell would be largely dependent on matching the name of the low Vt cell with a name of the high Vt cell in the library. For instance, functionally equivalent cells may be named ANDHVT20 and ANDLVT20, where H stands for high-vt and L stands for low-vt so as to form a basis for name-based cell replacement. This name based approach has other potential drawbacks. For example, it may be unclear what Vt-based selection criteria to use if a corresponding low Vt cell or high Vt cell counterpart to a given cell does not exist in the library. The name based mapping process also places a heavy reliance upon correct designation of cell names in vendor libraries. Occasionally, an HVT cell may be incorrectly designated as an LVT cell in a vendor library, which can lead to degradation of overall results in terms of power.
Moreover, prior synthesis flows often comprised an initial optimization using low Vt cells followed by leakage reclamation using high Vt cells. Unfortunately, this synthesis flow has drawbacks. For example, leakage power obtained with this prior flow may not be optimal since the initial passes did not use high Vt cells for optimization.
Thus, there has been a need for improvement in the selection and use of cells for multiple threshold voltage optimizations during synthesis. The present invention meets this need.

Selection of cells from a multiple threshold voltage cell library for optimized mapping to a multi-Vt circuit


A system (18) includes: a) A vehicle (12) includes an attitude or angular velocity control system (38), a plurality of star trackers or star sensors (22) each having a field of view (28); b) a memory (30) having a star catalog (32), an allocated area for a star pair catalog (58) and a reference table (56) stored therein; and c) a processor (24) coupled to the attitude or angular velocity control system (38), the star trackers or star sensors (22), and the memory (30). The processor (24) populates the star pair catalog (58), using the method described herein. The processor (24) then periodically determines the vehicle inertial attitude or angular velocity or sensor alignment, based, in part, on the star pair catalog (58) and reference table (56). The novel ability of the software to autonomously populate the star pair catalog (58) allows users to avoid uploading a large amount of data, and the problems associated with such an upload.

The present invention relates generally to attitude or angular velocity or sensor alignment estimate adjustment for a vehicle, and more particularly, to algorithms involving attitude or angular velocity or sensor alignment determination, using star position measurements.
Satellites and other vehicles are in widespread use for various purposes including scientific research and communications. Many scientific and communications missions, however, cannot be accurately fulfilled without consistently monitoring and controlling the 3-axis attitude and angular velocity of the vehicle. Attitude may be described as the vehicle orientation with respect to some frame, for example, the Earth-Centered Inertial (ECI) frame. In many applications, the vehicle must be oriented to transmit signals in particular directions or to receive signals from specifically located sources. Furthermore, in such a situation, the vehicle angular velocity must be such so as to maintain the desired orientation, over time. Without accurate control over vehicle 3-axis attitude and angular velocity, the transmission or reception of such signals is hindered and at times impossible.
Such control requires systems for 3-axis attitude and angular velocity determination, which generally include one or more star trackers and a 3-axis gyroscope. During normal operation, star trackers or star sensors provide attitude-related information and the 3-axis gyroscope provides angular velocity information. As there are inherent, and time-varying, errors from star trackers, star sensors, and gyros, it is often necessary to constantly estimate such errors, in order to compensate for them. One common method of doing so is to correlate star tracker or sensor position measurements of stars with known positions of the same stars, as listed in a star catalog, or database. Discrepancies between the measured and predicted positions allow direct estimation of tracker error, and indirect estimation of gyro error. Knowing such errors allows estimation of attitude or angular velocity, or refinement of existing estimates. Furthermore, if there are multiple star trackers or star sensors on-board, such correlations allow determination of the alignment of such trackers or sensors, with respect to each other; such determination yields greater accuracy in future attitude and angular velocity estimates.
Upon initialization, procedures such as described above often require a method for obtaining a coarse estimate of attitude, where, for example, attitude is considered to be the orientation of the vehicle with respect to the ECI frame. Typically, this method includes two steps. The first step is to identify stars detected by one or more of the star trackers or star sensors as known stars from an astronomical database. A star catalog, which is an astronomical database or portion thereof, is used for this purpose. Each entry of the star catalog contains information about a particular star, such as the star's position in the ECI frame. Each entry is associated with a star catalog index, allowing a user to locate the entry. The second step of the method is to use the following to obtain the vehicle attitude: the knowledge of the stars' positions with respect to some frame, which is represented in the database; the knowledge of the stars' positions in the star tracker frame, which is output by the star tracker or star sensor; and the knowledge of the alignment of the star sensor or tracker with respect to the vehicle body.
A star pair database, also referred to as a pair database, or a pair catalog database, may be used to aid in the identification procedure of the first step of the method described above. The star pair database contains a reference table, and a star pair catalog, also referred to as a pair catalog. The reference table is to aid in accessing entries from the star pair catalog. Each entry of the star pair catalog represents a pair of stars, where each star in the pair is represented in the star catalog. All possible star pairs may not be represented; for such a design, there exist criteria to decide which star pairs are to be represented in the pair catalog. Such criteria may be based upon, for example, magnitude of stars in the pair, or angular separation between the stars forming the pair.
As will be recognized by those skilled in the art, the star pair database may be used in a multitude of ways to aid the identification procedure of the first step of the method described above. For example, in a situation where a vehicle of an unknown attitude includes a star tracker or star sensor that detects a pair of stars, separated by a measurable angular separation, a pair catalog can help in the identification process. (The method for determining angular separation from tracker or sensor measurements is described later in this application.) For use in such a situation, the pair catalog would be designed so that the entries would be ordered by separation angle, the angular separation between the stars forming the pair, as measured by the star sensor or star tracker on the vehicle. Should the detected star pair be a pair represented in the pair catalog, its representation would be in an easily determined section. This is because the detected star pair has an angular separation equal to the separation measured by interpretation of the star tracker or star sensor data, plus or minus instrument error. As instrument error is typically small, this reduces the number of possible matches between the detected star pair and the cataloged star pair from, for example, several thousand to perhaps a dozen or two. Other techniques may be used to determine which of the remaining pair catalog entries actually represents the detected pair.
Pair catalogs are typically large, comprising tens of thousands of entries. Pair catalogs often need to be changed over time, for various reasons. For example, proper motion of stars causes angular separation between stars forming pairs to change; this requires a change of pair catalog entries or order of the entries in the pair catalog. For designs that require the pair database to be on-board the vehicle, changing a pair catalog will often require an upload of the modified pair catalog, or sections therein, from a remote location. For example, should the vehicle be a satellite already in orbit, the upload must be done from a ground station, possibly during limited periods of contact with the satellite. Such an upload can be time-consuming, and, in the event of error, or transmission failure, hazardous. Therefore, it is desirable to design a method of pair catalog update or change such that the pair catalog upload, and associated problems or risks, are not required.

Method and apparatus for on-board autonomous pair catalog generation


A sifting device having an upper chamber and a lower chamber. An upper chamber offset opening is disposed on the end wall of the upper chamber and offset from a central axis. A shaft rotates about the central axis of the upper chamber. A blade in the upper chamber and attached with the shaft. The blade is configured to rotate between an open position and a closed position. A cone element is disposed on the blade and concentric with the upper chamber. A lower sifting element is disposed within the lower chamber. The shaft attached with the lower sifting element such that the lower sifting element rotates in the lower chamber when the shaft rotates. The upper chamber offset opening is configured to allow powdered substance to move from the upper chamber to the lower chamber so that the blade and lower sifting element can sift powdered substances.

People all around the world have enjoyed fresh hot food for thousands of years. Vending machines have been one way to provide food to people. The earliest known to vending machine dates to first century Roman Egypt. The vending machine accepted a calling to dispense holy water. When the coin was deposited, it fell upon a pan attached to a lever. The lever opened a valve which let some water flow out. The pan continued to tilt with the weight of the coin until it fell off, at which point a counterweight snapped the lever up and turned off the valve.
The first modern coin-operated vending machines were introduced in London in the late 1880s. Various types of food and snack vending machines exist in the world. Typically, food vending machines provide shelf stable foods such as chips, cookies and cakes and other snacks. Some vending machines have been used to make hot foods such as pizzas.
One of the major problems with vending machines that make hot foods is the cleanliness of machines. More specifically, one of the issues with food related or pizza vending machines is that the flour cannot be sifted correctly which is key for making fresh, tasty pizza. Without having flour being sifted before making pizza and other fresh oven cooked food, the food is not tasty.
Another major problem associated with sifting flour is that in many jurisdictions regulations exist that bags of flour cannot be stored on the machine. Additionally, another major problem with vending machines related to cooking food or materials is that the size of machine necessary to cook food. Additionally, another major problem with vending machines is the inability of the machine to dispense the necessary toppings or condiments that people use, such as salt, pepper, garlic powder, red pepper flakes etc.
As a result, there exists a need for improvements over the prior art and more particularly for a more efficient way of providing a machine capable of dispensing food in a better way to automate sifting flour that is suitable for the vending machine.


Methods and systems are disclosed for network congestion management. The methods and systems receive a first packet complying with a first network protocol comprising a first congestion indicator representative of a presence or absence of network congestion and further comprising a first set of data associated with a second network protocol, and provide an indication of the presence or absence of network congestion generated based, at least in part, on the first congestion indicator. The methods and systems also receive a first packet complying with a first network protocol comprising a first set of data associated with a second network protocol, and output a second packet complying with the first network protocol comprising a first congestion indicator representative of a presence of network congestion.

Networks are increasingly being deployed with components that utilize the InfiniBand protocol. An InfiniBand network can provide a number of benefits over a network that utilizes more traditional Ethernet and Internet protocols including, for example, a relatively higher signaling rate and a relatively lower latency. However, many network devices are not configured to utilize the InfiniBand protocol, and instead utilize Ethernet and Internet protocols. For example, a computer often will have a network interface controller ("NIC") to enable the computer to communicate using Ethernet and Internet protocols, but a computer may not have a host channel adapter ("HCA") to enable the computer to communicate using an InfiniBand protocol.
One technique for obtaining the benefits of InfiniBand in an environment with network devices that are not configured for InfiniBand is to utilize Ethernet over InfiniBand ("EoIB") or Internet Protocol over InfiniBand ("IPoIB"). With EoIB and IPoIB, a network device may send an Ethernet or IP packet that is received by another device that encapsulates the received packet into an InfiniBand packet. In other words, if using EoIB or IPoIB, the data within an Ethernet or IP packet may be placed within an InfiniBand packet. The InfiniBand packet may traverse an InfiniBand network and may also be decapsulated when exiting at appropriate points such as the InfiniBand network so that traditional Ethernet or IP network devices may read the packet. However, problems with congestion management may arise when utilizing IPoIB and EoIB.
In particular, congestion may occur at a network switch if, for example, the rate of packets passing through the switch is higher than the switch's throughput capacity. Typically, if congestion occurs at a switch, the switch will react according to the protocol of the switch. For example, a packet may be sent from a source computer to a destination computer via a number of switches. Typically, for example, if the packet complies with an Ethernet protocol and is received by router or an Ethernet switch, the router or Ethernet switch may determine that there is congestion. In response to determining that congestion is present, a router or an Ethernet switch may set a value in an Explicit Congestion Notification ("ECN") field of the packet to notify the destination computer of the congestion and/or may send a packet to the source computer in compliance with a Quantized Congestion Notification ("QCN") to notify the source computer of the congestion. The source computer and destination computer could then react and adjust to the congestion. Additionally or alternatively, a router or Ethernet switch may drop one or more packets in response to determining that congestion is present.
Similarly, if a packet sent by a source computer complies with an InfiniBand protocol and is received by an InfiniBand switch, the InfiniBand switch may determine that there is congestion. In response to determining that congestion is present, the InfiniBand switch typically may set a value in a Forward Explicit Congestion Notification ("FECN") field of the packet to notify the destination computer of the congestion and, after receiving the packet, the destination computer may send the source computer a packet with a set value in a Backward Explicit Congestion Notification ("BECN") field.
However, in a mixed-protocol environment such as EoIB and IPoIB, the traditional methods of resolving congestion may not be effective. For example, if a value in a FECN field of an IPoIB packet is set by an InfiniBand switch, the FECN field may be lost when the packet is decapsulated en route to the destination computer.
Improvements in network congestion management technology, including network congestion management technology in a multi-protocol environment, are desirable.

Methods and systems for network congestion management


A network attached storage system includes at least one data moving device coupled to a control station for receiving commands from the control station, each of the at least one data moving devices including a board having mounted thereon a file server portion and a power control portion, wherein the power control portion receives a continuous power supply and controls the application of power to the file server portion based on commands from the control station.

As is known in the art, Network Attached Storage (NAS) is a data storage mechanism that allows a host device to access storage devices using an Internet Protocol (IP) network. NAS devices are generally file servers that are referenced using IP addresses and are coupled to storage media, such as a RAID array or the like. The NAS therefore serves as a gateway between the storage media and the network. One example of the use of NAS can be found in the Celerra NS600 Network Server, from EMC Corporation of Hopkinton Mass. which includes a front end NAS enclosure and a back end Clariion storage enclosure.
One advantage of the NAS structure is that it enables data storage, data security and data management to be centralized in an environment with many servers running different operating systems. In addition, the use of a NAS-based system such as the Celerra system from EMC is a simple and straightforward way for a host to expand its storage capacity through the use of existing IP host functionality.
Although NAS-based systems are useful, to provide consistent, high performance client support, businesses typically rely on high availability systems. In the prior art, high availability characteristics have been added to a NAS system by duplicating the data mover front end enclosure. For example, a block diagram of an exemplary NAS architecture 10 with some high availability characteristics is shown in FIG. 1. The NAS 10 includes a pair of data mover enclosures 16a and 16b which control the movement of data to and from the attached storage device (not shown). In the example of FIG. 1, each data mover enclosure is shown to include two data movers, which together provide some level of high availability to the overall NAS by enabling continued data mover operation in the event of a single point of failure. A control station 12 is used to monitor the operating status of the data movers. A switch is disposed between the control station 12 and the data mover enclosures 16a and 16b for forwarding control information between the control station and the data movers. Data that is read from or written to the data storage device is forwarded to and from the data movers via an External Local Area Network (LAN), not shown.
Although the NAS architecture 10 provides some level of high availability, because the architecture uses only a single switch and control station, a single point of failure can cause the control system to fail, and therefore the system may not have the required rate of reliability.
FIG. 2 shows an exemplary high availability NAS architecture which overcomes single point of failure issues. The high-availability NAS 20 includes two control stations 12 and 22 coupled via two switches to the two data mover enclosures 16a and 16b. In the event of a single point of failure at any of the components, the remaining component can cover for the failed component while it is repaired.
The solution of FIG. 2 is thus capable of providing high availability support in a NAS environment. One particular problem with such an arrangement, however, involves the physical connections between the individual components of the system. Each line in FIG. 2 that connects one component to another component represents a connection between the components, such as an Ethernet cable. As the components are doubled, the number of cables is linearly increased to ensure that all necessary connections for supporting the high availability system can be maintained. For example, the four cables that were previously used to couple the data movers to the switch are increased to eight cables. The sheer number of cables that would need to fit within the enclosure makes such an arrangement undesirable, and makes any further scaling of the design prohibitive.
Referring briefly to FIG. 3, a diagram of the exemplary NAS enclosure system of FIG. 2 is shown illustrating the clutter of cables within the enclosure, including Ethernet cables from the switches 14 and 24 to the components, and control cables (for example RS485 control cables) from the control stations 12 and 22 to the components.


An integrated circuit device as a first IC chip, a second IC chip, and a circuit board having a hole formed therein that is large enough to permit the second IC chip to be accommodated therein. The first and second IC chips are bonded together so as to be electrically connected together, and the first IC chip is mounted on the circuit board with the second IC chip accommodated in the hole formed in the circuit board. Here, one of the IC chips forming a chip-on-chip structure is accommodated in the hole formed in the circuit board, making further thickness reduction possible. Moreover, the obverse surfaces of the IC chips are located closer to the circuit board, making possible wireless mounting of the IC chips, despite forming a chip-on-chip structure, on the circuit board through connection using bumps. This helps reduce trouble due to inductance in a circuit that handles a high-frequency signal.

1. Field of the Invention
The present invention relates to an integrated circuit device having IC chips forming a so-called chip-on-chip structure, in which two IC chips are bonded together through bumps or by another means so as to be electrically connected together.
2. Description of the Prior Art
Conventionally, when two semiconductor chips are mounted on a circuit board, they are sometimes bonded together through bumps or by another means so as to be electrically connected together (hereinafter referred to as a xe2x80x9cchip-on-chip structurexe2x80x9d). As compared with mounting two chips separately, adopting a chip-on-chip structure offers the advantage of making of the area required on a circuit board smaller.
However, conventionally, as shown in FIG. 7, IC chips 100 and 200 forming a chip-on-chip structure are usually simply placed on a circuit board 300, and thus tend to increase the overall thickness. Moreover, the obverse surface of the IC chip 100 (i.e. that surface of the IC chip 100 to which the IC chip 200 is bonded and on which electrodes are provided) faces away from the circuit board 300, and therefore the wiring pattern (not shown) formed on the circuit board 300 needs to be connected to the IC chip 100 by the use of wires 400 such as gold wires. As a result, in particular in the case of a circuit that handles a high-frequency signal, the inductance of the wires 400 tend to cause poor or uneven sensitivity.
Moreover, in the case of a circuit that handles a high-frequency signal, it is essential to provide shielding against noise. Conventionally, as shown in FIG. 8, such shielding is realized by the use of shielding material 500. Providing shielding in this way, however, not only requires a large amount of shielding material, and thus hampers cost reduction and weight reduction, but also further increases the overall thickness. This often makes an arrangement like this unusable in thin devices such as IC cards and cellular telephones.
An object of the present invention is to provide an integrated circuit device having IC chips forming a chip-on-chip structure that helps achieve further thickness reduction and that minimizes trouble due to inductance in a case where a high-frequency signal is handled.
Another object of the present invention is to provide an integrated circuit device having IC chips forming a chip-on-chip structure that reduces the amount of shielding material required, or even eliminates the need therefor, in providing necessary shielding and thereby helps achieve cost reduction and weight reduction.
To achieve the above objects, according to one aspect of the present invention, an integrated circuit device is provided with a first IC chip, a second IC chip, and a circuit board having a hole formed therein that is large enough to permit the second IC chip to be accommodated therein. Here, the first and second IC chips are bonded together so as to be electrically connected together, and the first IC chip is mounted on the circuit board with the second IC chip accommodated in the hole formed in the circuit board.
In this arrangement, one of the IC chips forming a chip-on-chip structure is accommodated in the hole formed in the circuit board. This helps achieve further thickness reduction. In addition, the obverse surfaces of the IC chips (i.e. the surfaces on which the IC chips are bonded together) are located closer to the circuit board. This makes it possible to mount the IC chips, even though they form a chip-on-chip structure, on the circuit board on a wireless basis (without using wires), i.e. through connection using bumps or by another means. In this way, it is possible to reduce trouble due to inductance in a circuit that handles a high-frequency signal.
The circuit board may have shielding pattern formed around the portion thereof where the first IC chip is connected to the circuit board. This makes it possible to shield the noise coming from where the IC chip is connected to the circuit board, and thus helps enhance the shielding effect.
Shielding material connected to fixed potential point may be provided in the hole formed in the circuit board. This permits the portion of the circuit board on which the IC chips forming a chip-on-chip structure are mounted to be surrounded by the shielding material connected to the fixed potential point and by the reverse surfaces of the IC chips (the surfaces of the IC chips opposite to the surfaces thereof on which they are bonded together), which also offer a shielding effect. Thus, it is possible to obtain a sufficient shielding effect.
The shielding material has only to be somewhat larger than the smaller of the IC chips forming a chip-on-chip structure. This helps reduce the amount of shielding material required as compared with conventional arrangements and thereby achieve cost reduction and eight reduction. By making the shielding material somewhat larger than the larger of the IC chips forming a chip-on-chip structure, it is possible to obtain a higher shielding effect.
According to another aspect of the present invention, an integrated circuit device is provided with a first IC chip, a second IC chip, and a multilayer circuit board having a recess formed therein that is large enough to permit the second IC chip to be accommodated therein. Here, the first and second IC chips are bonded together so as to be electrically connected together, and the first IC chip is mounted on the multilayer circuit board with the second IC chip accommodated in the recess formed in the multilayer circuit board. Moreover, a wiring pattern connected to a fixed potential point is formed around the recess formed in the multilayer circuit board.
In this arrangement, one of the IC chips forming a chip-on-chip structure is accommodated in the recess formed in the multilayer circuit board. This helps achieve further thickness reduction. In addition, the portion of the multilayer circuit board on which the IC chips forming a chip-on-chip structure are mounted is surrounded by the wiring pattern connected to the fixed potential point and formed inside the multilayer circuit board and by the reverse surfaces of the IC chips (the surfaces of the IC chips opposite to the surfaces thereof on which they are bonded together), which also offer a shielding effect. Thus, it is possible to obtain a sufficient shielding effect. Since the wiring pattern formed inside the multilayer circuit board is used as shielding material, there is no need to provide shielding material separately, and thus it is possible to achieve further cost reduction and weight reduction.


The invention concerns a device and a method for ultrasensitive detection comprising an electrically inert porous sheet sandwiched between two positively charged fine electrodes. The invention uses the capacity of the electrodes, resulting from their powerful electrostatic properties, for sensing marked antibody complexes related to antigens detected in the sample, and to leave marked antibodies non-complexed with said antigens free. The method consists in depositing a sample droplet on the porous material sheet upstream of the electrodes and in detecting downstream of the electrodes, in a signal-zone, the possible presence of an antigen-antibody complex which has diffused in the porous material. The invention is useful for detecting some millipicogrammes of antigen per milliliter of sample.

The devices and methods of the prior art for performing precise immunological diagnoses generally use devices having most often already been the object of an immunological preparation (by immobilization of a first antibody). Thus the wells of the plates used in the ELISA type processes comprise in general a coating comprising first antibodies to capture an antigen, which will then be recognized by a second antibody, the whole being then revealed by a third anti-immunoglobulin antibody. The good practice of this process requires at least six washings and three hours of incubation.
Rapid tests have appeared during the 1980s, that use microballs previously clad with a first antibody and which migrate on a nylon surface to come to rest ultimately on a first line (presence of antigens) of second antibodies, for stopping in all cases on a second line of third antibodies. The whole takes place in several minutes, using a minimum of 7 nanograms of antigen per milliliter of specimen. This process does not permit detecting serum antibodies.
The object of the present invention is no longer an electrophoresis which is characterized by a more or less prolonged migration between two electrical poles (one at the beginning and the other at the end), as a function of molecular weight of different proteins. There exist more or less sophisticated gel techniques conducted between two electrodes and which permit separating a group of proteins in different bands according to their molecular weight.
The present invention has for its object to overcome the insufficiency of sensitivity of the known methods, in particular to provide a process permitting obtaining a qualitative or quantitative signal of the presence, at infinitesimal concentrations, of a substance in fluids of a specimen, even if it is not constituted by a nucleic acid. The so-called PCR (polymerase chain reaction) technique detects very small quantities of fragments of chromosomic material (RNA or DNA). It is not capable of measuring proteins such as new generations of tumoral markers or cytokenes circulating at quantities that can be less than a picogram per milliliter (a billionth of a gram). The immunological techniques, even the most sensitive such as radioimmunoanalysis, do not permit it.
The process according to the invention is applicable to the detection of any analyte that may be contained or adapted to be included in a fluid or a liquid which can react with a specific ligand to form a complex, the analyte or the ligand or both being carriers of electronic charges which are neutralized, or even reverse in the complex when the latter is formed. It is characterized in that:
the fluid or liquid is caused to migrate, after placing it in contact with the specific ligand, in an electrically inert porous material interposed between opposite surfaces of two electrically charged electrodes of the same polarity, and
there are detected in the liquid that has migrated into the porous material between the two electrodes, those components, analyte, ligand or complex, which were not captured by the electrodes.
Needless to say, the total volume of fluid or liquid used, which is that contained in the dissolved condition of one of said components or both, particularly as a result of their possible mixing, must be sufficient to permit its diffusion in the porous material to the place where the detection is carried out.
According to the nature of the constituent detected, or not detected, therefore depends the conclusion that can be drawn as to concentration. In a preferred embodiment of the method according to the invention, one of the constituents, for example the ligand, is marked. It is for example an antibody which carries free NH2 groups, therefore positive charges (the analyte being thus an antigen), and if the electrodes are negatively charged, the detection of the marker in the fluid or liquid having migrated into the porous material between the electrodes will show that the antibody is engaged in a complex, hence that the antigen was present in the original liquid or fluid. Thus following the antigen-antibody reaction, the NH2 groups of the antibodies are masked in the formed complex, the positive charge of the antibody being thus neutralized, the antigen-antibody complex being again, as the case may be, able to have a negative polarity. On the contrary, the absence of detection will translate into the absence of the antigen in the fluid or liquid studied. Thus the marked antibodies which have not encountered xe2x80x9cpartnersxe2x80x9d are thus captured and blocked by the negatively charged electrodes.
Other examples show in what follows this description, important possibilities offered by the invention. But for good understanding of the invention, it may be useful to define the expressions xe2x80x9canalytexe2x80x9d and xe2x80x9cligandxe2x80x9d, as used in the present description. Thus, the application of the invention is not limited to the detection of analytes constituted only by antigens or antibodies, even if it is in this connection that the invention will be most often used.
By analyte, should be understood any molecule or entity which it is desired to detect, no matter what its nature: haptene, protein, antigen, antibody, nucleic acid fragments, substance, even a group of molecules having common characteristics, this analyte being adapted to give rise to a specific reaction with a ligand to form a complex adapted to take part in a reaction seeking to detect in a selective manner the presence or absence of the analyte in a fluid or a liquid, for example a fluid of biological origin.
In the case of an analyte constituted by an antigen, it will be appreciated that the antibody, which thus plays the role of the ligand, is the carrier of NH2 sites which give it a positive polarity, giving rise to the possibility for this antibody to be captured by an electrode having negative charges, whether the latter is of electrostatic nature or the result of placing the electrode under voltage in the suitable direction. Naturally, the converse can also take place. It can happen, for example, that in other types of analyte-ligand couples, the polar group will be formed from a negatively charged group, for example a COOH group, which will be neutralized in the analyte-ligand complex that is formed.
Accordingly, the ligand can as needed be itself modified by a group giving it its properties, for example the required electrical polarity for its use in the method of the invention. This could, by way of example, be the case when the analyte is constituted by a DNA fragment, whose presence can be searched for in a liquid after it has itself been used in a complementary RNA detection test. In such a case, the DNA fragment will be for example rendered the carrier of a biotin group, the ligand thus acceptable to be used-being adapted to be constituted by avidine, carrying itself, as the case may be, a marker, for example colorimetric, fluorescent, chemiluminescent, radioactive or the like and, if there was further need, a supplemental group giving it an electrostatic charge, which could thus be neutralized during the production of the analyte-ligand complex whilst susceptible to being formed, via the biotin-avidine reaction. Or else the analyte could be constituted by a DNA fraction and the ligand by a DNA probe itself marked by an enzyme, particularly peroxidase, by means of spacer arms produced by means of heterobifunctional systems, for example of the (DNA (FMCC)-peroxidase (SPDP) type.
Preferably, the analyte is in solution in a liquid or a fluid. But for example when the analyte consists of an antigen, it can also be contained for example in a biopsy or mucous fragment. But it then should be extracted by, or carried in, the liquid which will then migrate in the porous material between the electrodes.
As to the xe2x80x9cporousxe2x80x9d material, it must necessarily be meant by this expression any material permitting to propagation or diffusion of a liquid through its mass, when it has been moistened with this liquid. It could be constituted of any open pore material, fibrous material or which can behave as an absorbent, etc . . .
As to the electrodes, use can be made of any material adapted to be electrically polarized or electrostatically charged. Numerous materials in the form of thin sheets are available commercially: see for example the chapter beginning at page 53 of the catalog xe2x80x9cDIMACEL Compounds and Related Electrostatic Packagingxe2x80x9d.
Those skilled in the art could obviously think of numerous different applications for the invention. This will be the case for any detection of a predetermined substance or xe2x80x9canalytexe2x80x9d using a highly specific reaction with a corresponding xe2x80x9cligandxe2x80x9d. It will in all cases be possible, without the exercise of invention and if the need arises, to modify one of the constituents of the reaction to give it a polarity which will be neutralized, or even reversed in the final reaction product, wherein the method of the invention can also be applied to it. Similarly, those skilled in the art will in each case be able to adapt the method of the invention, for example to choose polarities to be given to the electrodes to render it operational for the detection of any analyte adapted to form a specific compound with a given ligand, when this formation is also accompanied by a neutralization, or even a reversal of the electric charge, either of the analyte, or of the ligand.
Thus more generally, when the polarities of the charges carried by the ligand and those of the electrodes are of opposite sign, the complex is detected in the liquid having migrated between the two electrodes when the initial having migrated between the two electrodes when the initial liquid contained the analyte.
Furthermore, when the polarities of the charges carried by the ligand and that of the electrodes are of the same sign and the polarities of the charges carried by the analyte and the complex itself are of opposite sign, there will be detected only the possible excess of ligand initially used when the analyte was initially present.
As has already been mentioned, it is advantageous that the ligand bear a marker, in particular a marker transformable into a colorometric, fluorescent or chemiluminescent signal and that the signal zone comprise a detector of the marker, in the signal zone that the liquid reaches that has migrated through the porous material, between the electrodes.
The signal zone is itself preferably formed in a porous material in contact with that which is interposed between the electrode, so as to permit access in the signal zone to the liquid having migrated first through the porous material interposed between the electrodes, and then through the porous material comprising the signal zone.
In one of its preferred embodiments, the method according to the invention thus uses the electrical attraction or repulsion exerted by two or more electrodes (preferably thin and flat), on one of the constituents of the analyte-ligand couple, for example on immunoglobulins (lg) accordingly as the immunoglobulins are bound or not to their specific antigen. A microdrop of specimen to be tested is disposed on the porous material, itself generally formed by a thin sheet, upstream of the latter or in the upstream region of the electrode pair, the drop of specimen being then absorbed immediately by the porous sheet, often an insulating paper. Then there is deposited a volume of marked antibody solution which will mix with the previously deposited drop of specimen. If the antigen that is sought is present in the drop of specimen, it will be rapidly captured by the marked antibodies. The electrodes will then differentiate between an antibody complexed with the antigen and an antibody which is not encountered antigen in the droplet, in particular when traversed by a negative electric current. In this case, the electrodes capture the NH2 sites (positively charged) of the immunoglobulins which are not bonded to an antigen, and permit migration of the immunoglobulins (lg) whose NH2 site is this time saturated and masked by an antigen in the porous sheet, between the two electrodes, up to the signal zone in which they can be detected and measured, when they have first been prepared before the determination (conjugated with an enzyme or a radioactive marker or any other means).
But these electrodes can also be positively charged or be traversed by a positive current, this time repelling the NH2 sites of the immunoglobulins (lg) that have remained free from any bonding to an antigen. They will on the other hand capture the lg+antigens complexes which all have a sufficient number of negative charges, thus captured by this positive electrode. There thus occurs an inversion of the signal at the end of preparation: the signal is supplied only by the lg remaining free from any antigen.
Combinations of pairs of electrodes can also be used, associated with the porous material, in particular when it is sandwiched successively between a first pair and then, downstream of the latter, with a second pair of electrodes, the electrodes of this second pair being also charged and of identical polarities to each other, but of a sign opposite that of the polarities of the electrodes of the preceding pair, the detection being then carried out upstream of the second pair of electrodes, after the liquid has migrated through the porous material first through the first, then through the second pair of electrodes. This procedure thus permits also semiquantitative dosage, to the extent that the first pair of electrodes can retain only a predetermined quantity as the case may be, either the marked ligand, or of the complex formed, the final detection thus indicating only the excess as the case may be, either of the complex formed, or of the analyte initially present in the fluid or liquid that is studied.
Preferably the first pair of electrodes is of a sign such that, and is calibrated so as to trap a predetermined maximum quantity of the analyte in the form of an analyte-ligand complex, and there is detected downstream of the second pair of electrodes the excess of analyte which the fluid or a liquid initially contained.
This thus permits practicing semiquantitative determinations: the negative electrodes capture all the free immunoglobulins and the positive electrodes, which are smaller, capture only a portion of the lg+antigen complexes, this portion of the complexes corresponding to the physiological quantity of antigen that is not to be exceeded. If there is excess of this antigen, the positive electrodes could not capture all the complexes formed and a signal would thus be given, indicating the excess of this antigen beyond the physiological quantities.
An important advantage of the invention is the rapidity of determination. Between deposit of the specimen of the marked antibody solution, and the appearance of the result, takes hardly more than 5 to 10 seconds. The reason is that the attraction or repulsion of the antibodies is instantaneous, whilst if this reaction were entirely immunological (attraction of the complex antibody+antigen by a second antibody preliminarily fixed for example), an incubation would be necessary. Thus, the immunological reaction takes place in the insulating or electrically inert porous sheet immediately after the deposit. This immunological reaction can be accelerated by a factor of 10,000 times by the addition of suitable reagents (such as polyethylene glycol 8000 for example). The reaction which then takes place between the electrodes is thus not immunological but rather electrical, and hence instantaneous, which gives to this invention an essential quality for emergency determinations (for example, myocardial enzymes during infarction, forecast of an imminent embolism by determining D-Dimere or coagulation factors after bone surgery or in phlebitis, etc . . . ).
It is important that the antibodies comprise before the reaction free NH2 groups. It is thus preferable that the antibodies remain monomers and that the marking takes place without the production of aggregates or polymers of the antibodies using the free NH2 groups. In case of the formation of polymers or antibody aggregates, the NH2 sites of the aggregated antibodies risk being masked, which will reduce correspondingly their capacity to be captured, particularly by the negative electrodes. The process could nevertheless be used, but with less sensitivity, to the extent the antibodies comprise a sufficient number of NH2 groups adapted to intervene in the antigen-antibody reaction or, in the absence of antigen, to be captured in a sufficiently energetic way.
The preceding situation must in a very preferred way be avoided. Moreover, the marked antibodies (or other marked ligands) must be exempt from any free marker, even traces thereof, above all if there is involved an enzyme adapted to modify a substrate (or group of molecules forming a substrate). During production, for example, of conjugated antibodies marked with peroxidase by known techniques, it will be generally required to proceed with a purification of the marked antibodies by several molecules of peroxidase by techniques also known, particularly by chromatography of the reaction product so as to retain only the peaks of elusion containing the marked antibodies by several molecules of peroxidase and to eliminate all the others, plus those containing molecules of free peroxidase.
The marking of the monomeric antibodies can be carried out according to a very high ratio of molecules of marking per molecule of antibody, which can reach a value of 5. Recourse could also be had to mixtures of monoclonal antibodies, all marked, but recognizing epitopes respectively distinct from the antigen to be detected, which will increase all the more the sensitivity of detection.
The extreme sensitivity of the process in a number of its applications is due to several reasons:
the materials used are all inert (porous material or electrodes) and do not fix any molecule of a protein as do the ELISA methods responsible for important background noise which prevents sensitive measurements. Foreign protein or foreign antibody can be fixed, which gives rise to the total absence of background noise.
the signal zone contains the most sensitive reagents and the most rapid to react with the marking of the antibodies arrived there
finally, the high sensitivity of the electrodes does not leave any of the xe2x80x9ctrappablexe2x80x9d antibodies free, but above all does not trap any xe2x80x9cnon-trappablexe2x80x9d antibody molecule adapted to give the signal. What can give the slightest signal can only correspond to a marked antibody and not to background noise.
In the present invention, it is not only a matter of separating or causing to migrate differentially the different molecular weights; it is moreover a matter of detecting or rejecting immunoglobulins according to whether they are bonded or not to their specific antigen. The molecular weight plays no role because the technique works perfectly as well with Fab fragments from IgG (the lightest) as with IgM supposed to be heavier.
In the present invention described here, the electrodes do not support any reaction. They play only, during the short instant in which a fluid migrates through the porous material, their electrical role of repulsion or attraction. This is the result of the migration of the fluids after passage between these electrodes, which supplies a signal, and not the electrodes.
As a modification, the ligandxe2x80x94or analytexe2x80x94is deposited dry on a predetermined region of the porous material, in a region essentially upstream of the electrodes, the fluid or liquid presumed to contain the analytexe2x80x94or the ligandxe2x80x94being introduced into this zone of the porous material.
For example, it is the analyte which is deposited in said predetermined region essentially in a region upstream of the electrodes. Preferably, it is also the analyte which is the carrier of the electrical charges, the fluid or liquid presumed to contain it being thus introduced into the region where the ligand is deposited; after possible in situ production of the complex, a separate dose of the analyte itself is reintroduced into the same region, the latter being this time marked, and the possible presence of the marked analyte is detected in the liquid having migrated between the electrodes.
The invention also relates to a device for the detection of an analyte adapted to be contained in a liquid, by reaction with a specific ligand of the analyte to form a complex, the analyte or the ligand or both being carriers of neutralized or even opposite electric charges in the complex when the latter is formed, this device comprising:
at least one pair of two electrodes provided with surfaces which face each other and are electrically charged, with identical polarities, or adapted to be thus charged;
a porous material, itself electrically inert, interposed between the surfaces and permitting the diffusion within it, between said electrodes, of the liquid adapted to be deposited in a free region of this porous material, essentially upstream of its path of migration through this porous material;
means in combination with this porous material permitting the detection in the liquid having migrated through the latter, between said electrodes, of those of these components, analyte, ligand or complex, which have not been detected by the electrodes.
Preferably, the electrodes are formed of sheets that are statically charged or adapted to be thus charged and the porous material is itself formed of a sheet sandwiched between the two electrodes, this porous sheet extending downstream of said electrodes relative to the direction of migration and comprising in the external portion of the detection means, the constituents that have migrated.
This device is preferably provided with means for detecting a marker carried by one of the reagents, for example the ligand.
The means associated with said material or electrically inert porous sheet, are themselves preferably constituted by a porous sheet in contact with the first and through which can diffuse the liquid having migrated through the first to come into contact with the indicator contained in this second sheet.
In the description which follows, reference will be made more particularly to the situations arising the most frequently, for which the method and device of the invention are called upon to apply, those of the detection of particular antigens by predetermined specific antibodies (or vice versa).

Electrostatic device and method for immunological detection


A spark plug includes a ground electrode and a center electrode. The ground electrode comprises a ring shaped member which is centered on the center electrode. A beveled ring shaped surface of the ring shaped member generally faces the center electrode. This increases the spark area of the ground electrode, providing for more consistent and stronger sparks, and even multiple sparks. A cross shaped channel is disposed centrally on a distal face of the center electrode. Because of the increased spark area which the channel provides, the spark is more likely to travel along the channel, rather than jump from point to point along the distal face of the center electrode, as can happen with conventional spark plugs; thus, the channel provides a stronger and more consistent spark.

1. Field of the Invention
The present invention relates to spark plugs.
2. Description of the Related Art
In order to provide the greatest possible fuel economy, performance, and power, it is important for spark plugs to fire consistently, and to provide strong sparks.
New types of spark plugs have been developed which try to provide stronger sparks and more consistent firing. U.S. Pat. No. 5,430,346 to Johnson provides a spark plug with a generally ring shaped ground electrode. This provides greater spark area compared to a conventional ground electrode, and provides multiple paths which the spark can follow between the center electrode and the ground electrode. These features contribute to stronger sparks and more consistent firing.