A computer-implemented method, computer program product, and computer system for selecting strangers for information spreading on a social network. For the strangers who are users of the social network and not related to each other, information spreading probabilities based on features, information reach, and information spreading probabilities based on a wait time are computed. Fitness scores of the strangers are computed; the fitness scores are a function of the information spreading probabilities, the information reach, and the information spreading probabilities. The strangers are ranked, based on the fitness scores, in a sorted set. One or more of the strangers for the information spreading are selected from the sorted set. The one or more of the strangers for the information spreading are selected by determining an interval in the sorted set, and the interval satisfies an optimization objective of minimizing time for the information spreading within a confidence probability.

The present invention relates generally to social network analysis, and more particularly to selecting strangers for information spreading on a social network.
Social networks are more and more widely used for information sharing and exchange. Hundreds of millions of messages are posted on social networks daily. Due to widespread usage and growing number of users of social networks and due to businesses around social networks, there are enormous interests in modeling behaviors of the users of social networks. Such models benefit a number of objectives, such as viral marketing, spreading messages for social or political reasons, and protecting certain populations and organizations. Many models focus on macro levels of social networks rather than an individual's characteristics; the models don't describe how strangers in social networks spread information when asked by another stranger or strangers in social networks.

Selecting strangers for information spreading on a social network

International Business Machines Corporation


A power supply for providing excitation to notification appliance circuits (NACs) in fire alarm applications meets revised national and international requirements for both NAC drive and auxiliary load drive tasks with a single circuit configuration. The requirements stipulate ability to tolerate inrush when activating strobe lights and horns of ten times the nominal output, while limiting short-circuit drive in AUX mode to eight amperes after five seconds. The novel power supply improves on the requirements, first by continuously testing for overcurrent NAC status and signaling faults in real time, and second by shutting off AUX drive in event of a short and retrying periodically without a requirement for manual reset. Thus testing for wiring errors is rendered safer and nondestructive, and correction of a wiring error can be quicker.

Fire alarms are characteristically robust electrical/electronic devices, expected to resist abuse and events such as installer error, while maintaining functionality for extended periods with minimal maintenance. Typical fire alarm apparatus may employ automated sensors as triggering devices, which can include detectors for such hazards as smoke, heat, toxic vapor, and combustion products, along with manually actuated alarm stations. In addition to signal inputs, a fire alarm system necessarily includes outputs. Outputs can include, depending on the requirements of an application, acoustical, visual, and/or other signals distributed throughout a facility, message transmitters directed to emergency responders, facility managers, and the like, actuators such as fire door auto-closure functions, security lock releases, manufacturing process shutdown command signals, and such other functions as may be dictated by the requirements of an individual application.
Fire alarm systems typically employ premises power sources—nominal 115 or 230 VAC at 50 or 60 Hz single-phase is widely available—for normal operation of entire systems. Higher-power sources and specialty supplies can be incorporated where needed or preferentially available, such as DC, three-phase AC, a non-standard supply voltage or frequency, or the like.
Fire alarm system internal electronics generally employ power having a configuration appropriate for the technology. Thus, earlier systems may have used, for example, relays powered directly from premises power to actuate notification appliances—light and/or sound generators—distributed throughout a facility, while many successor systems have adopted DC power at lower voltages for their less power-demanding but more effective equivalent appliances. With the adoption of intrinsically safe low voltage DC power to actuate high-efficiency strobe lights and horns, a need to employ licensed electricians to install and maintain system components has diminished, potentially reducing costs.
Designs for applying power to notification appliance circuits (NACs) and auxiliary (AUX) functions of fire alarm electronics using distribution wiring are subject to laws in many jurisdictions, as well as to regulations and conventions that may have the force of law. Marketing pressure may likewise dictate particular approaches to apparatus design, in consideration of compatibility between vendors, regional and worldwide standards, cost, and other issues. For example, any telephone "dialer" device is likely to use a dual tone, multi-frequency (DTMF) code sequence, as originally developed by Bell Laboratories and now adopted substantially universally, to initiate all calls.
New regulations are scheduled for imminent adoption, both within the U.S. and in jurisdictions such as Canada, for which harmonization with U.S. regulations is largely in force. These regulations stipulate fire alarm circuit performance attributes such as transient current draw during normal NAC operation and short circuit foldback current versus time for AUX operation. While multiple alternatives are possible to address these regulations, many obvious solutions to implement the regulations are undesirably costly or complex. Similarly, conventional, non-regulation based technical solutions, such as use of manually reset protective devices, may be undesirable in a competitive and convenience-oriented marketplace.
Accordingly, it is desirable to provide a method and apparatus for supplying actuation power to distributed fire alarm notification appliance circuits and auxiliary loads whereby high transient current survival, intelligent power foldback, and automatic foldback recovery coexist in an economically practical configuration.

Fire alarm notification power supply with configurable notification appliance circuits and auxiliary power circuits apparatus and method


An encoder encrypts a message by generating a nonce, using a first encryption key to encode the nonce, splitting the message into a first part and a second part, using the first encryption key and the encoded nonce to encrypt the first part of the message into a first ciphered part, using a second encryption key, the encoded nonce and the first ciphered part to generate an initialization vector, using the first encryption key and the initialization vector to encrypt the second part of the message into a second ciphered part, and generating a ciphertext comprising the first ciphered part, the second ciphered part, the initialization vector and the nonce. A decoder uses a reverse process to decrypt the message. The decryption comprises generating a copy of the initialization vector, which is compared to the initialization vector in order to verify that the message is properly decrypted.

One of the important challenges in the field of information technology (IT) relates to the need to provide confidentiality and integrity in the transmission of messages. For example, Authenticated Encryption (AE) schemes are intended to fulfill these goals, particularly for messages consisting of plaintext. To this end, AE schemes combine an encryption scheme with a Message Authentication Code (MAC). AE with Associated Data (AEAD) is intended to be a general and secure construction of AE. AEAD intends to provide confidentiality and integrity of plaintexts, as well as integrity of non-secret information referred to as associated/additional data. Advanced Encryption Standard-Galois Counter Mode (AES-GCM) is the most popular standard AEAD today.
AEAD provides a high security level for symmetric encryption as long as the underlying schemes satisfies some requirements.
Synthetic Initialization Vector (SIV) mode is recently proposed AEAD scheme, denoted AES-GCM-SIV, that is resistant to IV misuse. FIG. 1 (Prior Art) is a schematic diagram of an authenticated encryption with associated data (AEAD) technique using a synthetic initialization vector (IV) for encoding a message. A message M may contain information in any one or a broad range of types and formats, containing, without limitation text, sound, image, code, and the like, in sizes ranging from kilobytes to gigabytes. Associated data A may be provided and be related to the message M. The associated data A may for example include a timestamp, a context and/or accounting information related to the message M. A nonce N is generated, being for example randomly generated. The nonce N, the message M and the associated data A are fed to a message authenticated code function (MAC) using a secret key L, this MAC function being denoted as FL. The MAC function FL produces an initialization vector IV. The message M and the initialization vector IV are fed to a generic encryption function using a secret key K, denoted εK.
The secret key K may for example be a symmetric key. The encryption function εK outputs a ciphertext C, which is an encrypted version of the message M. The initialization vector IV produced by the MAC function FL is also output, for example in the form of a tag.
The nonce N, the ciphertext C and the initialization vector IV may be provided to a decoder having cognizance of the secret key K and of the secret key L. The decoder applies the received ciphertext C to its own copy of the encryption function εK to regenerate a copy M′ of the message M and a copy IV′ of the received initialization vector IV. The decoder compares the copy IV′ to the initialization vector IV. If the copy IV′ is identical to the received initialization vector IV, the message M has been properly decoded; otherwise the message is deemed to be improperly received and is ignored. The copy M′ of the message, the initialization vector IV (or its copy IV′) and the nonce N are applied to a copy of the MAC function FL to generate a copy A′ of the associated data A.
However, it has been observed that many things go wrong with solutions as illustrated in FIG. 1. For example, if the AES-GCM scheme is used with repetition of the same IV under the same encryption key, confidentiality of messages may be completely lost. Unfortunately, IT practitioners have misguidedly believed that encrypted data may prevent cipher-text malleability and/or tampering.
The SIV solution is frequently impractical because of its performance issues, particularly in contexts where hardware acceleration is not possible, as in the case of streaming on devices having performance constraints, for example a lack of sufficient processing capacity.
Consequently, there is a need for improvements in the areas of message confidentiality and integrity protection.

Methods, encoder and decoder using encryption and authentication functions for encrypting and decrypting a message


A vehicle emergency brake system has a second brake for braking a vehicle by increasing the frictional resistance with the road surface, a millimeter wave radar for detecting any obstacle in an advancing direction, a pedal speed sensor for detecting the step-in speed of a brake pedal for actuating a first brake, and a controller for actuating the second brake. If hard braking by the first brake is detected by the pedal speed sensor, the controller determines whether the vehicle is going to crash into an obstacle detected by the radar. If a determination is made that it will collide, the second brake is actuated. Thus, it is possible to reliably actuate the second brake in an emergency.

When a vehicle is traveling on a road surface having a low friction coefficient, such as a frozen road, a wet paved road, or a dry paved road where sand is disposed, the grip of the tires with respect to the road surface falls, so that the wheels tend to slip. Thus, heretofore, with a brake system for braking the rotation of wheels mounted on the vehicle (first brake), even if hard braking is activated, the braking distance may increase excessively so that the vehicle may collide against an obstacle, irrespective of whether the vehicle is traveling at a high speed or a low speed.
On a road surface having such a low friction coefficient, since the degrees of slipping tend to be uneven for individual wheels, travel of the vehicle tends to be unstable, so that the vehicle may collide against an obstacle in an oblique direction. As means for allowing stable travel of a vehicle, such systems as an ABS (Antilock Brake System), which detects the degree of slip for every wheel and controls the braking force of each wheel, and VSC (Vehicle Stability Control) for controlling the engine output and the braking force of the wheels by detecting the steering tendency of the vehicle with a yaw rate sensor and a lateral acceleration sensor are used practically. But in order for these systems to operate effectively, it is a prerequisite that the grip of the tires remain to a certain extent.
In order to avoid collision of a vehicle on a road surface having a low friction coefficient as mentioned above, apart from a conventional brake system, it is proposed to mount a second brake for braking the vehicle in a short distance by increasing the frictional resistance with the road surface. As the second brake, there are ones which spray slip-preventive materials such as sand and ice particles between the tires and the road surface (See for example patent documents 1 through 3.), ones in which a liquid adhesive is applied to the tire surfaces to stick slip preventive materials to the tires (See for example patent document 4.), ones in which thawing of the frozen road is prevented by blowing cold air on the tires (See for example patent document 5.), ones in which a braking plate or a toothed braking wheel is pressed against the road surface (See for example patent documents 6 through 8.), and ones in which the pressing force of the vehicle against the road surface is increased by inflating a gas bag outwardly of the vehicle (See for example patent document 9.), etc. (patent document 1; unexamined JP patent publication 4-38204, patent document 2; unexamined JP patent publication 7-309101, patent document 3; unexamined JP patent publication 8-25905, patent document 4; unexamined JP patent publication 63-2706, patent document 5; unexamined JP patent publication 50-100703, patent document 6; unexamined JP patent publication 49-2228, patent document 7; unexamined JP patent publication 54-122528, patent document 8; unexamined JP patent publication 8-40222, patent document 9 unexamined JP patent publication 6-286586.)


A locking differential has a fixed drive dog and a movable drive dog. A locking actuator has a plunger drivingly connected to the movable drive dog. The plunger is movable in a first direction to a lock position in which the drive dogs are engaged and in a second, opposite direction to an unlock position in which the drive dogs are disengaged. A piston is connected to the plunger and disposed in a cavity in a housing. Movement of the piston in the second direction is imparted to the plunger when the plunger is in the lock position but the piston is movable independently relative to the plunger in the first direction when the plunger is in the unlock position. A pressurized fluid causes the piston, and thereby the plunger, to move in the second direction. A piston bias member biases the piston in the first direction, and a plunger bias member biases the plunger in the first direction. A related method of locking the differential is also disclosed.

Wheel-driven machines, such as dump trucks for example, are typically provided with at least one inter-axle differential, commonly referred to as an "open differential", having a carrier or differential housing and two output shafts or half shafts that each drives one wheel of the machine. As well known, the differential utilizes a gear system that permits the output shafts, and thereby the driven wheels, to rotate at different speeds, thereby reducing transmission loads and understeering during normal cornering. In a machine with front and rear driven axles, each driven axle is typically provided with an open differential, and torque is transmitted to the driven axles through a transfer case interconnecting the axles. The transfer case is generally provided with a so-called center differential to accommodate differences in rotational speed between different axles and the wheels driven thereby.
Under slippery or otherwise poor surface conditions, however, open differentials may result in a loss of traction. As well known, if one wheel or axle driven through the differential loses traction, the other wheel or axle loses input torque. Therefore, known differentials are commonly provided with a differential lock to selectively neutralize the normal differential action by locking the output shafts to the differential housing. For example, a dog-clutch locking arrangement has been provided in known spur-type differentials and includes a fixed drive dog connected to and rotating with the differential housing and a slidable drive dog rotating with but slidable along one output shaft. When the drive dogs are not mutually engaged, the differential operates as a conventional open differential. When the drive dogs are mutually engaged, the output shaft connected to the slidable drive dog is locked to the differential housing and the other output shaft is indirectly locked to the differential housing via the planetary gearing of the differential.
To control the locking and unlocking of the differential, the slidable drive dog is connected to the plunger of a hydraulic actuator mounted on the differential casing. The drive dogs are disengaged by applying hydraulic pressure ahead of a piston fixed to the plunger to retract the plunger and separate the drive dogs. To lock the differential, the hydraulic pressure is removed, and a spring forces the piston and the plunger to an extended position whereby the slidable drive dog is moved into engagement with the fixed drive dog, thereby locking the differential.
A problem arising in the use of such known locking arrangements is that, when the hydraulic pressure ahead of the piston is removed, viscous drag on the piston from the hydraulic fluid and the high effective inertia of the fluid in the hydraulic system results in relatively slow movement of the piston and plunger and, therefore, the slidable drive dog. This is especially the case when the hydraulic fluid ahead of the piston is cold. Accordingly, the slidable drive dog is slow to fully engage the fixed drive dog or the drive dogs will not fully engage at all.


Firewalls and network address translators (NAT) provide many advantages for client and the Internet itself, however, these devices break many existing transmission control protocol (TCP)/Internet Protocol (IP) applications, since they conceal the identity of IP clients (i.e., peers) and block transmission control protocol (TCP) call setup requests. Firewalls and NATs make it impossible for one TCP peer to discover another and establish a connection. Embodiments of this invention provides a system and a protocol to enable two TCP peers that exist behind one or more firewalls and NATs to automatically setup a true peer-to-peer TCP connection and exchange data without making changes to the firewall or NAT devices or existing TCP-based applications. In embodiments of this invention, the synchronization between the blind TCP peers is achieved using a system that consists of a registration server, an agent application, and a virtual network interface that together relay and replicate the control signals between the two TCP peers. In addition, embodiments of this invention are also used to traverse the NAT and establish a bi-directional peer-to-peer TCP connection in the firewall.

1. Field of Invention
Embodiments of this invention relate to the field of Internet Protocol (IP) networks, Transmission Control Protocol (TCP), Peer-to-Peer protocols and more particularly to the traversal of firewalls and network address translators (NATs) for TCP connections.
2. Discussion of Related Art
The Internet has been designed around a client server model where many clients initiate a connection to communicate with a single server, for example many web-browsers accessing a web-server, which is know as a client-server model and protocols to support this model have been develop such as HTTP, FTP, etc. However, this model is not well-suited for many types of applications where only two parties need to communicate, for example in an Internet voice or chat conversation, where one peer may initiate a connection with another peer. This model is known as a peer-to-peer model.
Recently, the Internet Engineering Task Force (IETF) and other private organizations have developed peer-to-peer protocols such as Session Initiated Protocol, H.323, Gnutella, etc. to enable peer-to-peer communication. However, these peer-to-peer protocols and applications break when one or more peers exist behind a firewall and network address translator (NAT).
Firewalls and NATs provide many advantages for clients and the Internet itself, such as improved security and improved Internet Protocol (IP) address management and do not pose problems for many client-server applications (such as HTTP) since most servers are publicly available and the client initiates the connection with the server. However, these devices do cause problems for peer-to-peer protocols and applications. Firewalls and NATs conceal the identity of IP clients (i.e., peers) and block transmission control protocol (TCP) call setup requests. Firewalls and NATs make it impossible for one TCP peer to discover another and establish a connection with another. In effect, NATs and firewalls "blind" TCP peers from performing the necessary synchronization (i.e., handshaking) needed to setup a connection between two peers.
Transmission Control Protocol
A TCP connection contains three phases: connection establishment, data transfer and connection termination. The TCP protocol uses a Three Way Handshake protocol to synchronize and establish a connection between two TCP peers and once connected TCP hands off to the application for data transfer and communication.
While it is possible for a pair of end hosts to initiate a connection between themselves simultaneously, typically one end opens a socket and listens passively for a connection from the other. This is commonly referred to as a passive open, and it designates the server-side of a connection. The client-side of a connection initiates an active open by sending an initial TCP segment with SYN flag set to the server as part of the Three Way Handshake. The server-side should respond to a valid SYN request with a TCP segment with the SYN and ACK flags set. Finally, the client-side should respond to the server with a TCP segment with the ACK flag set, completing the Three Way Handshake and connection establishment phase.
The TCP Three Way Handshake protocol between a client and server is shown in FIG. 3. TCP functions by opening connections to a remote host and is thus connection-oriented. TCP maintains status information regarding the connections it makes and is therefore a reliable protocol guaranteeing data delivery, unlike the unreliable stateless User Datagram Protocol (UDP). A TCP connection is identified by the IP addresses and virtual port numbers used by both ends. During communication, additional numbers are used to keep track of the order or sequence number which indicates what order the segments of data should be reassembled. Finally, a maximum transmission size is constantly being negotiated via a fallback mechanism called windowing. The combination of port numbers, sequence numbers and window sizes constitutes a connection.
In the Internet protocol suite, TCP 703 is the intermediate layer between IP 705 below it, and an application 702 above it as shown in FIG. 7. Applications most often need reliable pipe-like connections to each other to transfer information. Applications send streams of 8-bit bytes to TCP for delivery through the network, and TCP divides the byte stream into appropriately sized segments (usually delineated by the maximum transmission unit (MTU) size of the data link layer of the network the computer is attached to). TCP then passes the resulting packets to IP, for delivery through an Internet to the TCP module of the entity at the other end. TCP checks to make sure that no packets are lost by giving each byte a sequence number, which is also used to make sure that the data is delivered to the entity at the other end in the correct order. The TCP module at the far end sends back an acknowledgement for bytes which have been successfully received; a timer at the sending TCP will cause a timeout if an acknowledgement is not received within a reasonable round trip time, and the (presumably lost) data will then be re-transmitted. The TCP checks that no bytes are damaged by using a checksum; one is computed at the sender for each block of data before it is sent, and checked at the receiver.
Firewalls and Network Address Translation
Most homes' and offices' Internet connections are managed by a router that performs firewalling and network address translating functions (NAT). These functions have become a standard features in routers for homes and small-offices even though according to specifications routers should not act as firewalls. However, it is a convenient and widely-used technique. The routers that perform these functions will be referred to as firewalls.
In a typical configuration, a local network uses one of the designated "private" IP address subnets (such as 192.168.0.x or 10.0.x.x), and a firewall on that network has a private address (such as 192.168.0.1) in that address space. The firewall is also connected to the Internet with a "public" address assigned by an ISP. As traffic passes from the local private network to the Internet, the source address on the packets are translated on the fly from the private addresses to a public address. The firewall tracks basic information about each active connection. When a reply returns to the firewall, it uses the connection tracking information it stored during the outbound phase to determine where on the internal network to forward the reply. To the sending host on the Internet, the firewall itself appears to be the source/destination for this traffic.
Clients behind firewalls do not have true end-to-end connectivity and cannot participate in some Internet protocols. Services that require the initiation of TCP connections from the outside network can be disrupted. Unless the firewall makes a specific effort to support such protocols, incoming packets cannot reach their destination.
There are four types of NAT operations used in firewalls [1]:                1. Full Cone        2. Restricted Cone        3. Port Restricted Cone        4. Symmetric
For a given internal address, the first three types of NAT maintain a mapping of this internal address that is independent of the destination address. The fourth type of NAT will allocate a new mapping for each independent destination address. Unless the NAT has a static mapping table, the mapping that opens when the first packet is sent out from a client through the NAT may only be valid for a certain amount of time unless packets continue to be sent and received on the mapped port of the firewall.
Full Cone
In the case of the full cone, the mapping is well established and anyone from the public Internet that wants to reach a client behind a NAT only needs to know the mapping scheme in order to send packets to it. For example, an internal host behind a NAT with IP 10.0.0.1 sending on port 7400 and receiving on port 7450, is mapped to the external IP address and port on the firewall of 220.127.116.11 and 12867. Anyone on the Internet can send packets to that IP address and port and those packets will be passed on to the client machine listening on port 7450.
Restricted Cone
In the case of a restricted cone NAT, the mapping to the external IP address and port pair is only opened up once the internal client sends out data to a specific destination IP address. Unlike a full cone NAT, an external host can send a packet to an internal host only if the internal host has previously sent a packet to the specific external host. However, since the mapping only depends on the internal host IP address and port, packets from different external hosts will both use the same mapping through the NAT.
Port Restricted Cone
A port restricted cone NAT is almost identical to a restricted cone NAT, but in this case the restriction includes port numbers. Therefore, the firewall will block packets from an external host with source IP address (188.8.131.52) and port (6478) until the internal host has sent a packet to that IP address and port. Again since the mapping only depends on the internal host IP address and port, if the client has sent out packets to multiple IP address port pairs, they can all respond to the client and all of them will respond to the same firewall mapped port.
Symmetric
A symmetric NAT is the most restrictive and is different from the first three in that a specific mapping depends on internal host—source IP address and port—as well as external host—destination IP address and Port. As in the case of the restricted NAT, the external mapping to the firewall IP address and port pair is only opened up once the internal host sends out data to a specific destination.
NAT with port address translation typically involves source address translation (SNAT), which maps the IP address and port of the internal host which initiated the connection to the firewall IP address and port; and its counterpart, destination address translation (DNAT) which reverses the mapping. In practice, both are usually used together in coordination for two-way communication.
The TCP handshaking protocol between a client in a private network and a public server is show in FIG. 4. No special setup is required for setting up a connection in this configuration.
Standard NAT Behavior
The function of a NAT is to translate from internal addresses and ports to an external firewall addresses and ports. A NAT by definition is not a firewall and therefore should do the simplest operation possible to achieve its objective. The default behavior is to alter the connection as little as possible [6]. This means that NAT will attempt to preserve the original source port and will not change it unless that port on the firewall is currently being used by another connection. If this source port is already allocated NAT will attempt to find the next highest value in its group 0-511, 512-1023 or 1024-65535 [6].
TCP Connection Management in Firewalls
The Transmission Control Protocol (TCP) is connection-oriented and stateful, which makes it much more manageable by a firewall than the connectionless User Datagram Protocol (UDP). For this reason, many firewalls do not allow UDP traffic to enter or leave their private networks.
Firewalls that mange the state of a connection (i.e., stateful) are inherently more secure than "stateless" counterparts which simply perform packet filtering. These firewalls track the state of the connection which should not be confused with the state of the TCP connection. Connection tracking refers to the ability to maintain state information about a connection in memory tables, such as source and destination IP address and port number pairs, protocol types, connection state and timeouts.
A typical stateful firewall is shown in FIG. 2. This diagram illustrates the general operation of most firewalls 200 where packets can be generated 205 and received 203 locally, as is the case when the firewall is executed on the local host itself, or received and forwarded to and from remote hosts, as is the case when many hosts share one firewall. All packets that are received from remote hosts whether private internal hosts or public external hosts, travel through the remote interface 201. Each packet that is received on the remote interface is processed by the Pre-Routing stage 202 where it may be destination network address translated (DNAT) if it needs to be routed through the private network or onto the local machine. If the packet is not destined for the local machine, then it is processed by the Forward stage 204 and the Post-Routing stage 206. In the Forward stage, rules may be applied on how to filter each packet, and at the Post-Routing stage source network address translation (SNAT) may be applied if it needs to be routed through the public network. If a packet is destined for the local machine then it is processed by the Input stage 203, and if the local machine generates it then it is processed by the Output stage 205 and next processed by the Post-Routing stage. At any stage, filter rules may be applied that drop and change packet information. It is assumed that the firewall uses stateful inspection by managing a connection-tracking table for all connections through the firewall.
An entry in the connection-tracking table contains information as to the source IP address and port and the destination IP address and port as well as the state of the connection. The possible states of each connection is are INVALID meaning that the packet is associated with no known connection, ESTABLISHED meaning that the packet is associated with a connection which has seen packets in both directions, NEW meaning that the packet has started a new connection or otherwise associated with a connection which has not seen packets in both directions, and RELATED meaning that the packet is starting a new connection, but is associated with an existing connection, such as an FTP data transfer. This state information may be used in designing filter rules for how TCP connections are managed. Once a connection in the firewall is in ESTABLISHED state, the connection may be valid and exist for days even without any data exchange.
Filter rules in firewalls are typically designed so that peers (i.e., clients) in the private network cannot receive incoming TCP connection setup requests and therefore cannot set up a connection. Firewalls block connections to peers by dropping special packets that are involved in the handshaking process of establishing a TCP connection. Firewalls effectively "blind" the TCP peers from seeing each other.
Firewall and NAT Traversal for TCP Connections
Firewalls and NAT devices are located at the edge of virtually all business and most residential DSL and cable modems bundle firewalls and NATs. Therefore, the firewall and NAT traversal problem is one that affects both business users and residential users who use Internet applications that employ UDP or TCP for Internet communication. TCP is a connection-oriented transport protocol that makes it more reliable and secure compared to UDP. For this reason, many Internet applications require a TCP connection for communication. Furthermore, because the lack of connection set up and therefore difficulty to manage in a firewall, many firewalls are configured not to allow UDP traffic to enter or leave the private network. Therefore, firewall and NAT traversal for TCP connections is a challenge that must be solved in order to deliver public IP-based services. Overcoming this traversal problem will lead to widespread deployment of IP services to any subscriber with a broadband connection.
The firewall and NAT traversal problem for TCP connections is much more difficult than for UDP since TCP is connection-oriented and it has a well-defined connection protocol that is effectively managed by the firewall. In addition, the two TCP layers themselves need to be synchronized.
This problem can be broken down into three equally important components:                1. Traverse the NAT        2. Establish a bi-directional TCP connection in each peer firewall        3. Synchronize the peer TCP layers
NAT traversal is a well-known and studied problem for UDP traffic [1,2,4,5 ]. The basic problem, which is common to both UDP and TCP, is that peers behind NATs are not reachable by external hosts. For TCP however, the problem is compounded since the firewall filters TCP control messages making it even more difficult to establish a NAT mapping in the firewall.
The role of the firewall is to protect the network from being accessed by unauthorized sources. It does this by decisions based on the direction of traffic flow. Typically in a private network, incoming traffic is only allowed if the connection was initiated from a device on the internal private network. Therefore, establishing a bi-direction TCP connection in a firewall is not a problem when the connection source (initiator) is behind the firewall and the destination is publicly available. In this case, the firewall will allow TCP segments with SYN flags set to leave network but not enter the network. Furthermore, only TCP segments with a SYN flag set can create a connection in a firewall, and the connection does not reach its ESTABLISHED state until the final TCP segment with ACK flag set is sent out (see FIG. 4). However, when both hosts are behind firewalls, there is a deadlock situation since neither host can initiate the connection. Any approach to solving this problem must allow secure two-way communication without any changes to firewall filtering rules, or reducing the current level of security provided by the firewall.
Two TCP peers need to exchange a series of control segments in order to setup a connection and exchange data, as shown in FIG. 3. When the TCP peers are behind firewalls and NATs, they cannot receive these control messages that are needed to establish a TCP socket connection so that the application can send and receive data. These TCP layers are blinded and need to be synchronized before a socket can be used by the application.

Protocol and system for firewall and NAT traversal for TCP connections


The objective of the present invention is to provide a photosensitive insulating resin composition which is highly sensitive to g-line and h-line and enables to form a surface-protecting film, an interlayer insulation film and a planarized film that are excellent in various properties including resolution, electrical insulation property and thermal shock resistance, a cured product and an electronic component having the cured product. The present photosensitive insulating resin composition comprises an alkali-soluble resin having a phenolic hydroxyl group, a radiation sensitive acid generator comprising an s-triazine derivative represented by the following general formula (1), and a crosslinking agent.

1. Field of the Invention
The present invention relates to a photosensitive insulating resin composition which is used for forming a surface-protecting film such as a passivation film and an overcoat film, an interlayer insulation film, a planarized film and the like for semiconductor elements or the like, an insulating cured product formed by curing this composition and an electronic component having this cured product. More specifically, it relates to a cured product that is excellent in resolution and leads to a high residual film ratio in the case of forming a permanent resist and that has excellent properties such as electrical insulation property and thermal shock resistance, a photosensitive insulating resin composition from which such a cured product can be obtained, and an electronic component having the cured product.
2. Description of Related Art
Polyimide-based resins are conventionally known to be excellent in heat resistance and mechanical properties so that they have been widely employed for forming a surface-protecting film, an interlayer insulation film and the like for semiconductor elements in electronic instruments.
Additionally, there have been proposed photosensitive polyimide-based resins having photosensitivity to improve the precision in film formation with accompanying elevation of the integration of semiconductor elements. For example, JP-A S54-145794 and JP-A H03-186847 respectively disclose a composition containing a photosensitive polyimide-based resin wherein a photocrosslinkable group has been incorporated into a polymide precursor via an ionic bond and a composition containing a photosensitive polyimide-based resin wherein a photocrosslinkable group has been incorporated into a polymide precursor via an ester bond.
However, these compositions are required to use a solvent for development since a ring closure step is needed for imidation. There is disadvantageous in that resolution is insufficient.
Further, JP-A H08-50354 discloses a negative type photosensitive composition wherein a multifunctional acrylic compound is added to an aromatic polyimide precursor, however, it is pointed out that this composition suffers from similar problems as discussed above.

Photosensitive insulating resin composition, cured product thereof and electronic component comprising the same

Abstract: [In the formula (1), R is hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxyl group having 1 to 4 carbon atoms, X is a halogen atom and Y is oxygen atom or sulfur atom.]


An ultrasonic, flow measuring device, comprising an ultrasonic transducer in a bore of a measuring tube, which ultrasonic transducer has an ultrasound window, wherein a guide vane is inserted into the bore of the measuring tube in front of the ultrasound window and perpendicular to the ultrasound window of the ultrasonic transducer.

Ultrasonic, flow measuring devices are applied often in process and automation technology. They permit easy determination of volume flow and/or mass flow in a pipeline.
Known ultrasonic, flow measuring devices frequently work according to the Doppler principle or according to the travel-time difference principle. In the travel-time difference principle, the different travel times of ultrasonic pulses as a function of flow direction of the liquid are evaluated. For this, ultrasonic pulses are sent at a certain angle to the tube axis both in, as well as also counter to, the flow direction. From the travel-time difference, the flow velocity, and therewith, in the case of known diameter of the pipeline cross section, the volume flow, can be determined.
Ultrasonic waves are produced, respectively received, with the assistance of ultrasonic transducers. Travel time is ascertained in according to U.S. Pat. No. 5,052,230 by means of short ultrasonic pulses.
In the case of inline, ultrasonic, flow measuring devices, the ultrasonic transducers contact the medium, or fluid. In this way, significantly greater sound power can be coupled into the fluid in comparison to clamp-on-systems, and the ultrasonic transducers can be acoustically decoupled from the measuring tube, whereby the ratio of wanted signal (sound transmission into the fluid) to disturbance signal (sound transmission into the surrounding measuring tube) is improved. Moreover, in this way, in spite of sound measuring paths extending inclined to the main flow, a sound in-coupling extending perpendicularly to the medium-contacting wall can be implemented, which makes the actual measurement effect independent of changes of the velocity of sound.
For fluid contacting mounting of the ultrasonic transducers, lateral openings in the measuring tube are required. The ultrasonic transducers are so secured that the sealing of the measuring tube is assured under all operating conditions. In order to maximize the ratio of wanted signal to disturbance signal, usually an arrangement of the ultrasonic transducers is used, in the case of which the ultrasonic transducers lie opposite one another in a direct line of sight. Alternatively thereto, arrangements are known, in the case of which the sound moves from the transmitter to the receiver via multiple reflections on the measuring tube inner wall.
For the ultrasonic, measuring methods usually applied in inline, ultrasonic, flow measuring devices based on the travel-time difference or a phase difference or a frequency difference, the axis, on which the ultrasonic transducers lie opposite one another, must not be arranged perpendicular to the measuring tube axis, in order to achieve the desired measurement effect. If it is desired, furthermore, that the flow be as undisturbed as possible through the ultrasonic, flow measuring device, excluded likewise is an ultrasonic transducer arrangement parallel to the measuring tube axis, because, in this case, the ultrasonic transducers or reflectors introduced into the measuring tube would lie within the flow.
From these limitations, there results for ultrasonic, flow measuring devices an ultrasonic transducer arrangement, which is typically inclined relative to the measuring tube axis, which leads in connection with the desired medium contact to bores extending transversely through the measuring tube, into which bores the ultrasonic transducers are then externally inserted. If the ultrasonic transducers do not protrude into the flow, e.g. in order that flow losses be minimized and for protecting the units against abrasion or damage, then there result between the ultrasonic transducers and the cylindrical surface of the flowed-through measuring tube, subsequently called the measuring tube boundary surface herein, fluid filled, hollow spaces.
Different flow states can exist in these hollow spaces, especially as a function of the Reynolds (Re) number. These flow states are influenced decisively by the interaction between the measuring tube boundary surface and fluid volume in the ultrasonic transducer bore hollow space. In cases, in which there occur in the hollow space velocity components in the direction of the sound measuring path, these components superimpose on the actual measured variable, namely the velocity components of the main flow in the direction of the sound measuring path. In this way, considerable measurement errors can arise, in the order of magnitude of several percent, depending on the ratio of the ultrasonic transducer bore diameter to the measuring tube inner diameter, respectively ultrasonic transducer hollow space length to measuring path total length.
An approach for correcting this measurement error is to determine the current Re-number and therewith to perform a targeted measuring error correction in the course of the signal processing. Described in U.S. Pat. No. 5,987,997 is a method, which cares for such a subsequent correction of the measured value deviations. Therein, it is provided, based on the ratios of velocities, or the differences of velocities, to determine the Re-number of the flowing fluid along at least two mutually differing measuring paths. This solution is, however, only of limited applicable, since, at the latest, for Re <1000 (=laminar flow profile), the velocity ratios no longer change and therewith a unique determining of the Re-number is no longer possible. Also, for Re >3000, the determination is not always unequivocal. Furthermore, it can in the case of this form of measuring error correction come to considerable additional measured value deviations: In the case of disturbed flow, e.g. behind tube bends or valves, there arise flow states with velocity ratios between different measuring paths in the inline, ultrasonic, flow measuring device, which the signal processing interprets as a certain Re-number, such that a corresponding correction factor should apply. The "real" Re-number, formed from the average flow velocity in the measuring cross section, can, however, be significantly different. Thus, the applied correction factor no longer fits the current flow state, so that an additional measurement error arises.
For preventing interaction between measuring tube boundary surface and the fluid in the above described hollow spaces, FIG. 11 of U.S. Pat. No. 3,906,791 shows a measuring tube flush fitting, lattice insert, which should be acoustically transparent, on the basis of appropriate dimensions. Disadvantageous with this solution is the expected acoustic attenuation, or scattering, of the sound as well as the danger of deposition in the lattice meshes in the case of fluids with solids fractions. FIG. 12 of this document shows a synthetic material, cover plate/membrane for the hollow spaces. Associated with this plate, however, is not only a weakening of the wanted signal, but also sound refraction, which is strongly temperature dependent. Also, the bubble free filling of the hollow space between ultrasonic transducer unit and the plate, a requirement, in the case of use with different static pressures, is quite difficult.
Japanese Patent 2003202254proposes a solution involving a kind of perforated partition to close off the described hollow spaces. The hollow space between ultrasonic transducer unit and perforated partition should be so embodied that laterally directed sound waves rapidly die out. Such an apparatus leads, however, due to the reduced sound opening, to a weakening of the wanted signal, could plug in the case of fluids with solids fractions, and leads, in the case of use in liquids, to possible trapping of air, which likewise affects the wanted signal strength disadvantageously.

Ultrasonic, flow measuring device having guide vanes provided to prevent secondary flow formation in the hollow openings for the transducers


The present invention relates to an electrically conductive composition for filling via-holes formed in an electronic circuit substrate containing an electrically conductive metal and a vehicle, wherein the content of the electrically conductive metal is 57 vol % or more, and the composition is a plastic fluid for which fluidity increases when external pressure is applied to the composition.

1. Field of the Invention
The present invention relates to an electrically conductive composition used to fill via-holes provided in ceramic or glass substrates or the like, and more particularly to an electrically conductive composition that is able to prevent entrapment of air when printing an electrically conductive composition into via-holes. In addition, the present invention relates to electronic components using this electrically conductive composition and to a method for producing those electronic devices.
2. Technical Background
Sites referred to as via-holes filled with an electrically conductive metal are formed in single-layer circuit substrates or laminated circuit substrates, in which a plurality of circuit substrates have been laminated, to improve continuity in the vertical direction (both directions or the direction of lamination) or thermal conductivity. An example of a typical process used to form these via-holes comprises: (1) preparing an electrically conductive paste, (2) filling the electrically conductive paste into sites where holes corresponding to via-holes are formed, and (3) drying and firing the paste.
An example of the art relating to an electrically conductive paste for via-holes is JP2003-324268. A paste containing 31.3 to 47.6 vol % of an electrically conductive metal (Ag) is used in the examples of JP2003-324268.
The paste is typically filled by screen printing. As shown in FIG. 1 (conventional art), an electrically conductive paste 10 is filled into holes on a substrate 20 through a metal mask 30. Since the paste has a certain degree of viscosity, when the paste is supplied, it may flow into the hole along the side walls of the hole and entrap air. If the paste is pushed into the hole using a squeegee 40 while in this state, the paste is filled into the hole with air still entrapped therein, thus, forming an air void 50. This entrapment of air is particularly prominent in cases of holes having a large diameter.
Thus, air is entrapped in via-holes with electrically conductive paste during via-hole printing. This causes structural defects such as voids and pin-holes after firing the substrate. These defects have a detrimental influence on electrical and thermal conductivity as well as on the smoothness of the fired surface.

Electrically conductive composition for via-holes


Electrocardiogram (ECG) recorded signals are processed by a computer-implemented method to substantially remove extraneous signals to produce intermediary signals, and to separate the intermediary signals using a non-orthogonal transformation method such as independent component analysis to produce independent components of signals. The separated signals are displayed to help physicians to analyze medical conditions and to identify locations of abnormal heart conditions.

1. Field of the Invention
The present invention relates to the field of medical devices and methods for processing cardiac signals.
2. Description of the Related Art
Electrocardiogram (ECG or EKG) recording is a valuable tool for physicians to study patient heart conditions. In a typical 12-lead arrangement, up to 12 sensors are placed on a subject's chest or abdomen and limbs to record the electric signals from the beating heart. Each sensor, along with a reference electrode, forms a separate channel that produces an individual signal. The signals from the different sensors are recorded on an ECG machine as different channels. The sensors are usually unipolar or bipolar electrodes or other devices suitable for measuring the electrical potential on the surface of a human body. Since different parts of the heart, such as the atria and ventricles, produce different spatial and temporal patterns of electrical activity on the body surface, the signals recorded on the ECG machine are useful for analyzing how well individual parts of the heart are functioning.
A typical heartbeat signal has several well-characterized components. The first component is a small hump in the beginning of a heartbeat called the "P-Wave". This signal is produced by the right and left atria. There is a flat area after the P-Wave which is part of what is called the PR interval. During the PR interval the electrical signal is traveling through the atrio-ventricular node (AV) node. The next large spike in the heartbeat signal is called the "QRS Complex." The QRS Complex is a tall, spiked signal produced by the ventricles. Following the QRS complex is another smaller bump in the signal called the "T-Wave," which represents the electrical resetting of the ventricles in preparation for the next signal. When the heart beats continuously, the P-QRS-T waves repeat over and over.
The measurements can be used to determine such features as the underlying rate and rhythm mechanism of the heart, the orientation of the heart (how it is placed) in the chest cavity, evidence of increased thickness (hypertrophy) of the heart muscle, evidence of damage to the various parts of the heart muscle (myocardium), evidence of acutely impaired blood flow to the heart muscle, or patterns of abnormal electric activity that may predispose the patient to abnormal cardiac rhythm disturbances. More specifically, such information can identify abnormally fast (tachycardia) slow (bradycardia) or irregular heart rhythms (arrhythmias), abnormal conduction of cardiac impulses—which may suggest underlying cardiac or metabolic disorders, occurrence of a prior heart attack (myocardial infarction), an evolving and/or acute heart attack, an acute impairment to blood flow to the heart during an episode of a threatened heart attack (unstable angina or coronary artery disease), adverse effects on the heart from various heart diseases or systemic diseases (such as high blood pressure, thyroid conditions, heart valve diseases, dilated cardiomyopathy, or other myocardial defects, etc.), adverse effects on the heart from certain lung conditions (such as emphysema, pulmonary embolus (blood clots to lung), etc.), certain congenital heart abnormalities, abnormal blood electrolytes (e.g., potassium, calcium, magnesium), inflammation of the heart or its lining (myocarditis, pericarditis).
The rhythm analysis first determines the origins of the predominant rhythm in the sample and chooses from the major categories consisting of electronic atrial pacing, atrial flutter, ectopic atrial rhythm, sinus rhythm, junction rhythm and atrial fibrillation, including asystole, tachycardia, trigeminy, bradycardia, bigeminy and atrial and ventricular fibrillations, pacemakers, implantable cardioverter defibrillator, electrical alternans—pericardial effusion, and the like. The morphology interpretation will determine the existence of ischaemic heart diseases and syndromes such as Wolff-Parkinson-White, Long QT interval Romano-Ward Syndrome and Lown-Ganong-Levine Syndrome, hypertrophy patterns such as stenosis, QRS abnormalities such as low voltage QRS, pulmonary disease pattern, QRS axis, conduction abnormalities, ventricular hypertrophy, infarction, ST+T abnormality with ventricular hypertrophy, dating infarcts, epicardial injury, pericarditis, early repolarization, nonspecific ST elevation, subendocardial injury, nonspecific ST depression, digitalis effect, junctional ST depression, ischemia, QRS-T angle and QT interval, atrioventricular (AV) block, acute pulmonary embolus, bundle branch block, hyper- and hypo-kalaemia, piggy-back heart transplant, digitalis effect, ST deviation, and other normal and abnormal signals.
Many publications have described studying cardiac signals and detecting abnormal heart conditions. Sample publications include U.S. Patent Publication No. 20020052557; Podrid & Kowey, Cardiac Arrhythmia: Mechanisms, Diagnosis, and Management Lippincott Williams & Wilkins Publishers (2nd edition, Aug. 15, 2001); Marriott & Conover, Advanced Concepts in Arrhythmias, Mosby Inc. (3rd edition, Jan. 15, 1998); and Josephson, M. E., Clinical Cardiac Electrophysiology: Techniques and Interpretations, Lippincott Williams & Wilkins Publishers; ISBN (3rd edition, Dec. 15, 2001).
Unfortunately, although ECG signals have been studied for decades, they are difficult to assess because ECG signals recorded at the surface of the skin or at the surface of the heart are mixtures of signals from multiple sources. Typically, it is relatively straightforward to measure the shape of the QRS complex since this signal is so strong. However, irregular shaped P-wave or T-wave signals, along with weak irregular oscillatory signals that suggest a heart arrhythmia are often masked by large pacemaker signals, or the strong QRS complex signals. Thus, it can be very difficult to isolate small irregular oscillatory signals and to identify arrhythmia conditions.
In addition, atrial and ventricular signals are sometimes undesirably superimposed over one another. In many cases, diagnosis of disease states requires these signals to be separated from one another. For example, it might be desirable to separate P wave signals from QRS complex signals, so that signals originating in an atrium are isolated from signals representing concurrent activities in the ventricle.
In some practices the ECG signals are electronically "filtered" by excluding signals of certain frequencies. Typically, filters are applied to ECG signals to remove extraneous signals or disturbances, such as those due to baseline drift, power line interference and interferences from other physiological sources. The signals may also be "averaged" to remove largely random or asynchronous data, which is assumed to the meaningless "noise." The filtering and averaging methods irreversibly eliminate portions of the recorded signals, including information that may be important to an accurate diagnosis. In addition, it is not known whether the more random data is truly "noise" and thus meaningless to an evaluation of the heart's condition. It might be that the signals removed by filtering are indicative of a disease state in a patient. One filtering method is disclosed in U.S. Pat. No. 6,308,094 entitled "System for prediction of cardiac arrhythmias," which uses Karhunen Loeve Transformation to reduce or compress cardiac signals into elements that are deemed "significant." As a result, the information that is deemed "insignificant" is lost.
Compared to other signal separation applications, separating ECG recording signals presents additional challenges. For example, the sources are not always stationary since the heart chambers contract and expand during beating. Additionally, the activity of a single chamber may be mistaken for multiple sources because of the presence of moving waves of electrical activity across the heart. If electrodes are not securely attached to the patient, or if the patient moves (for example older patients may suffer from uncontrolled jittering), the movement of the electrodes also undesirably generates signals. In addition, multiple signals can be sensed by the ECG which are unrelated to the cardiac signature, such as myopotentials, i.e., electrical signals from muscles other than the heart.
In addition, typically up to 12 leads of sensors are placed on the chest, torso, limbs, abdomen and/or back of a patient to enable the recording of multiple signals. Since each sensor generates one channel of an electronic signal, multiple sensors accommodate the recording of multiple signals. The signals are processed in the electrocardiogram device, and a display or recording is generated for use by medical personnel. The medical personnel, using their skills and training, evaluate the results to find and diagnose an abnormal cardiac signal. By using multiple channels of signals, the electrocardiogram can be used to identify or isolate abnormal heartbeats for evaluation and diagnostic purposes. However, it is time consuming and cumbersome to place multiple sensors and route their associated leads to the electrocardiogram. Further, such multi-lead packs are costly, may not be appropriately used in temporary or emergency situations, and impractical for medical personnel unless read through a long-term ECG recording for labeling abnormal heartbeats. When a 12-lead system can not be used, fewer leads may be applied, but there may be an associated decrease in the quality and detail in the resulting electrocardiogram recording. For example, a 3-lead sensor such as a Holter system may be used, typically to record the cardiac condition of a patient who is away from a hospital bed or stays at home.
Unfortunately, each channel (lead) of recorded ECG signals is typically a combination of signals from multiple sources originating from events occurring at different compartments of the heart, and strong signals such as QRS complex signals typically dominate other signals. Unwanted signals from other sources, such as signals generated by pacemakers or by non-cardiac muscle movements (such as the trembling of an elderly patient), may be included and combined in the ECG recordings. Therefore, it is desirable to separate the ECG signals into components of independent sources so that the separated components can be used for medical analysis of the patient's condition. For example, copending U.S. patent application Ser. No. 10/482,931, entitled "System and Method for Separating Cardiac Signals", discloses a system for separating a cardiac signal into its independent sources by using an independent component analysis process, and is incorporated herein by reference. Once separated, the components may be displayed or otherwise used for diagnosis and treatment.
Devices with 1 or more sensors are used in various scenarios, such as automated external defibrillators or other situations when the more robust 12-lead sensors can not be used. Compared to 12-lead, devices with less sensors are more affordable, easier to store, and easier to use. However, fewer sensors typically provide less detailed cardiac information, and are therefore useful for general evaluation only. Since only limited information may be derived from fewer lead systems, an incorrect or incomplete evaluation and diagnosis may be made, which may result in long-term medical complications or even death. Accordingly, the fewer lead system is typically replaced with a multiple-lead system (preferably a 12-lead system) as soon as practical.

Device and method for detecting cardiac impairments


A method of rejecting a Bluetooth communications request is disclosed. A portable device receives a Bluetooth communications request from a computing device. The communications request includes a device identification of the computing device. A list of trusted device identifications stored in a memory resource of the portable device is automatically accessed. The Bluetooth communications request is rejected in response to determining that the device identification is not in the list of trusted device identifications.

It is often desirable to share information in an electronic form with others in order to better communicate an idea. Bluetooth communication has been developed as an industry standard to enable many devices, typically, though not necessarily, portable devices, to communicate wirelessly over short distances at relatively low power levels.
Bluetooth's great strength as an open, interoperable standard is also a challenge. For example, if a Bluetooth-enabled device accepts incoming connection requests, its user may end up receiving many connection requests from other Bluetooth users. Responding to these requests, most of which responses will typically be to reject the connection, is a time consuming annoyance. Yet the option of not accepting incoming connection requests may automatically reject those few that are actually desired.
In addition to the nuisance factor, responding to connection requests consumes valuable energy, which is a precious resource for portable electronics. Not only does it take power to operate the Bluetooth radio and transmit rejection messages, but turning on a display and interacting with a user is typically an even greater energy burden.
Further, there are many security concerns with Bluetooth. Because it is an open standard, designed for interoperability, it is possible for essentially all Bluetooth-enabled devices to communicate with other Bluetooth devices. Hence, it is quite possible for one device to pretend that it is actually another, which is known in the security arts as a spoofing attack. While this may be detected at the lower levels of the Bluetooth protocol, such a spoof might not be obvious to a user making an accept/reject decision about an incoming connection request. And a spoofed connection may introduce virus software or steal valuable information.
Importantly, the process of one Bluetooth-enabled device finding another Bluetooth device to communicate with, known as "Bluetooth Discovery," is a time consuming, power hungry process. During discovery, a Bluetooth transceiver may send inquiry messages on a periodic basis in an attempt to find another Bluetooth-enabled device. Likewise, Bluetooth transceivers wishing to be "discovered" must periodically turn on and listen for such inquiry messages.
Because of potential differences in the periodic schedules of different Bluetooth devices and possible radio interference, it may takes many tens of seconds to successfully transmit and receive an inquiry message after two devices come within communication range. Once an inquiry message is received, the receiving device will typically send an inquiry response packet (message) containing, among other things, its Bluetooth Device Address. This subsequent exchange may take several seconds per device.
Consequently, developing a list of potential Bluetooth communication "partners" via the Bluetooth Discovery process may require upwards of half a minute, all the while consuming relatively high levels of power for RF transceivers and protocol processing. This is generally seen as an excessive burden to impose on the human users of Bluetooth-enabled devices, such as mobile phones and hand held computers.

Bypassing bluetooth discovery for devices in a special list


A timepiece mechanism structure for receiving and guiding at least one pivoting wheel set is provided. The structure includes at least one inseparable single-piece structure, including one inseparable single-piece frame which includes pivot housings aligned in pairs in a direction of alignment for receiving the pivots of an arbour of this pivoting wheel set, and each pivot housing is an open housing formed by a half bearing or by a dihedral, and includes at one end a stop bearing surface in this direction of alignment.

Relative positioning and geometry, in particular the parallelism of the pivoting wheel set arbours, determines the precision, working and longevity of timepiece mechanisms.
The utilisation of modular assemblies requires, in particular, perfect precision, because of the stacked independently pre-assembled sub-assemblies.
The concept of extremely high precision modules or cassettes allows large scale production to be combined with high quality goods.
Thus, modular sub-assemblies for timepiece movements are known, from EP Patent Application Nos 11193173.9 and 11193174.7 in the name of ETA SA. The mechanical modules disclosed in these Patent Applications are irreversibly pre-adjusted and assembled to ensure the durability of their settings.
However, in a conventional embodiment, the modules do not always permit a reduction in the number of components, which would both reduce production costs and simplify the assembly plan, enabling mid-level technical personnel to assemble and adjust the most complex functions, while guaranteeing the required geometrical precision.
JP Patent No S5149063 discloses wheel sets including end pivots which pivot in bearings made in the same U-shaped plate. NL Patent No 11224C in the name of Watson discloses a similar configuration.
US Patent Application No. 580046A in the name of Harrington discloses a similar configuration with a U-shaped plate and a parallelism adjustment means using screws.
US Patent Application No. 2582162A in the name of Baermann discloses a magnetic electrical counter bearing including a U-shaped frame containing two aligned two bearings in which the counting wheel set pivots.
CH Patent Application No 488169A in the name of Rego discloses a pivoting device for a compass hand, with a cup bearing carrying two bearings.
DE Patent Application No 2218663A1 in the name of Mueller Schlenker FA discloses balance wheel half bearings with a vertical arbour for the lateral assembly of the balance, closed by a plate including a groove cooperating with a projecting portion of revolution of the balance.
FR Patent Application No 2807160A1 in the name of Denso Corporation discloses a case including aligned bores in which there is guided an arbour including, on one side, a trunnion made of resinous material, and on the opposite side, a hard metal trunnion of smaller diameter to that of the resinous trunnion.


A filter cup having a shell with a plurality of apertures in an upper portion and an aperture free portion below the upper portion. A base plate adjacent the aperture free portion has at least one aperture therethrough.

Filter cups and filter cages are well-known devices often used in vacuums to support and/or protect a filter. Selected prior art filter cups and filter cages are described below.
U.S. Pat. No. 4,185,974 teaches a filter assembly 80 having a collar 82. The collar is designed to be secured to the lid 22. A filter cage 84 extends downwardly from the collar. The cage is comprised of a plurality of ribs 86. The ribs are constructed of plastic. The ribs are oriented so that the filter cage tapers from the portion secured to the collar to a bottom wall 94 of the cage. The ribs permit fluid, such as air, to flow between them into the filter element 150. An annular sleeve 106 extends upwardly from the bottom wall 94. A plurality of fluid slots are located in the annular sleeve.
U.S. Pat. No. 4,906,265 teaches a similar structure to that described in U.S. Pat. No. 4,185,974. More particularly, U.S. Pat. No. 4,906,265 teaches a filter assembly having a filter cage 20 having an open end and a closed end 24. The cage 20 is comprised of a plurality of vertical struts 26 which are circumferentially spaced apart. A plurality of open spaces 27 are defined by and between the vertical struts 26. The struts 26 are taught to taper slightly inwardly toward the closed end 24. A filter is located outside of the filter cage.
U.S. Pat. No. 5,344,559 depicts and describes a filter cartridge having two cylindrical filter cages 2, 3. Each filter cage has a plurality of openings 10 to permit fluid through the cages. A filter element 1 is disposed between the cages. Both ends of both filter cages are open.
U.S. Design Pat. No. D186,583 teaches a dust bag holder for a vacuum cleaner. The dust bag holder has an upper, circumferential lip connected to an upper portion of the holder. The holder has a plurality of slots located over the entire body portion. A plurality of holes is also located in the base of the holder.
U.S. Design Pat. Nos. D495,105 and D495,458 depict a filter cup assembly for a vacuum cleaner having an upper, circumferential lip and a mesh-like body downwardly depending from the lip. The mesh-like material appears to encircle the body except where four ribs extend between the lip and a bottom of the cup. A filter element is shown as being located within the filter cup in FIG. 2. The bottom of the filter cup, as shown in FIG. 6, is substantially solid.
U.S. Patent Application Publication No. US 2002/0011050 teaches a cylindrical separator 40, best seen in FIG. 11. Air passes through a preliminary filter element 44 of the separator. The air is drawn downwardly through a filter cup 120. A raised portion 70 of a motor cover 66 closes the base of the separator, except a plurality of apertures 72 in the cover 66 allow air to flow from the separator through the cover and escape into the atmosphere.
The prior art filter cups and filter cages described above suffer from several disadvantages. Specifically, the prior art cups and cages fail to protect the filter from directly impinging dirt and debris thus causing the filter to become clogged. Additionally, the prior art cups and cages fail to protect the filter from dirt and debris and also permit a sufficient quantity of air to flow through them and into the filter. In light of at least these disadvantages of the prior art devices, it would be advantageous to have a filter cup that protected the filter from dirt and debris from becoming lodged therein yet which freely permits air to pass through to the filter.


In an equalizing filter circuit having an input terminal 101, an output terminal 102, delay devices 104 connected in multi-stage to the input terminal 101, and a plurality of weighting circuits 105 which are branched from and connected to the plurality of delay devices to thereby combine respective output signals of the weighting circuits, gain adjustment of the weighting circuits is performed to determine a coefficient of the equalizing filter circuit without depending on a load connected to the output terminal. Thus, an amount of compensation for a distorted waveform may be enhanced. To this end, an impedance converting circuit 108 is connected between at least one weighting circuit and the output terminal.

In various transmission systems, a weighted and delayed equalizing filter circuit is often employed as one technological measures to electrically compensate for waveform distortions generating due to dispersion or loss in a transmission medium.
In FIG. 19, there is shown a circuit block diagram of a conventional weighted and delayed equalizing filter circuit. Incidentally, the circuit in question is often called as a Transversal Filter, a FIR (Finite impulse Response) digital filter, or a Feed Forward Equalizer. These types of circuits have been described in, for example, non-patent publication 1 (i.e., A. Borjak, et al., "High-Speed Generalized Distributed Amplifier-Based Transversal-Filter Topology for Optical Communication System," IEEE Trans. Microwave Theory Tech., Vol. 45, No. 8, pp. 1453-1457)
In FIG. 19, reference numeral 1201 designates a filter input terminal; 1202, a filter output terminal; 1203, a load generating in an output circuit connected to output terminal 1202 (it will be hereinafter referred to as an output load); 1204, delay devices or units(T) connected in cascade to the input terminal; 1205, weighting circuits; 1210, an adder which adds therein the outputs from the respective weighting circuits 1205; 1231, an output impedance of the input circuit, which is connected to the input terminal 1201; and 1232, an electric terminating resistance connected to the end of the delay devices connected in cascade.
A signal inputted into the present filter is delayed by a desired delay by respective of the delay devices 1204 to be outputted as respective output signals. Then, desired weight values (filter coefficient) are given by the respective weighting circuits 1205. The signals from these weighting circuits 1205 are added together by the adder 1210 to be eventually outputted via the output terminal 1202.
By applying this kind of signal processing, waveform deformation is compensated for in an electric signal while waveform equalizing is realized in optical communication by carrying out photo-electric conversion of an optical dispersion waveform by a photodiode or the like and by thereafter performing correction.
FIG. 20 exemplifies such a transversal filter circuit. The conventional transversal filter circuit of this type is described in, for example, non-patent publication 2 ("Differential 4-tap and 7-tap Transverse Filters in SiGe for 10 Gb/s Multimode Fiber Optic Equalization", International Solid-State Circuit Conference (ISSCC) 2003, Session, 10, Paper 10.4, pp. 180-181).
In FIG. 20, reference numeral 1301 designates a filter terminal; 1302, a filter output; 1303, an output load formed in an output circuit, which is connected to the filter output 1302; 1304, delay units connected in cascade to the input side; 1305, weighting circuits; 1306, delay units (T) connected in cascade to the output side; 1307, a load to terminate the cascaded delay units 1307; 1331, an output impedance of the input circuit connected to the input terminal 1301; and 1332, a terminating resistance. In this transversal filter, the output load 1303 forms an adder. By this circuit configuration, an input signal is given delays and weighting values so that desired waveform equalization can be achieved.


There is provided an internal voltage generating circuit that reliably supplies a constant internal voltage to the interior of a semiconductor device without regard to an external voltage, where the internal voltage generating circuit compares a first reference voltage with a first internal voltage fed back to generate the first internal voltage following the first reference voltage, receives the first internal voltage to generate a second reference voltage which is more insensitive to fluctuation of the external voltage than the first reference voltage, and compares the second reference voltage with a second internal voltage fed back to generate the second internal voltage which follows the second reference voltage and has a variation gradient smaller than that of the first internal voltage when the external voltage is changed, thereby supplying the second internal voltage to a circuit requiring stabilized internal voltage, which is obtained to increase stability and durability of the operation of the semiconductor device.

1. Field of the Invention
The present invention relates to circuits of semiconductor devices, and more particularly, to an internal voltage generating circuit for supplying a stabilized power source to the semiconductor device.
2. Description of the Related Art
Generally, as miniaturization of semiconductor devices proceeds, an electrical field stress applied to a unit cell frequently exceeds a tolerance limit, thereby greatly affecting the device lifetime. That is, standard operating voltage conditions maintain the operating voltage substantially equal to that used in the past, depending on the circumstances of the entire system, even though the operating voltage conditions should be readjusted to comply with the miniaturization of the device. Thus, the reliability of the unit cells is degraded.
A conventional semiconductor memory device, for example, uses an internal voltage adapted to characteristics of the miniaturized products, where an internal voltage is typically lowered from an external voltage inputted from the outside. In the following background description, internal voltages of conventional semiconductor memory devices will be described with respect to FIGS. 1 through 3, including several problems and disadvantages thereof.
FIG. 1 is a schematic block diagram illustrating a conventional internal voltage generating circuit. Referring to FIG. 1, the conventional internal voltage generating circuit includes a reference voltage generator 10 and an internal voltage driver 20. The reference voltage generator 10 receives an external voltage Vcc to generate a reference voltage Vref, and the internal voltage driver 20 compares the reference voltage Vref with an internal voltage IVC fed back to output the internal voltage IVC following the reference voltage Vref.
FIG. 2 is a circuit illustrating the reference voltage generator and the internal voltage driver of FIG. 1. Referring to FIG. 2, resistors R1, R2 and N-type CMOS transistor NM1 are coupled in series between the external voltage Vcc and ground voltage Vss in the reference voltage generator 10. A gate of the N-type CMOS transistor NM1 is connected to a node NO1 between the resistors R1 and R2, the reference voltage Vref being generated form the node NO1. A P-type CMOS transistor PM1 is coupled between the node NO1 and the ground voltage Vss, in which a gate is connected to a drain node NO2 of the N-type CMOS transistor NM1.
Thus, as the external voltage Vcc is changed, the level of the reference voltage Vref is also changed, thereby generating the reference voltage Vref at a certain level even though the external voltage Vcc increases over a specific level. Further, the internal voltage driver 20 includes a comparator DA1 and a driving P-type CMOS transistor DPM1. The comparator DA1 includes a well-known differential amplifier, and compares the reference voltage Vref generated from the reference voltage generator 10 with the internal voltage IVC fed back from the output stage to output a comparison signal. Then, low level of the comparison signal is outputted if the reference voltage Vref is higher than the internal voltage IVC, otherwise high level of the comparison signal is outputted.
The driving P-type CMOS transistor DPM1 responds to the comparison signal and controls the external voltage Vcc to output the internal voltage IVC. The internal voltage driver 20 causes the internal voltage IVC to follow the reference voltage Vref by comparing the reference voltage Vref with the internal voltage IVC fed back, to decrease the output voltage if the internal voltage IVC is higher than the reference voltage Vref, but to otherwise increase the output voltage.
However, since the conventional internal voltage generating circuit generates the internal voltage IVC according to a level of the reference voltage Vref provided by the reference voltage generator 10, the level of the internal voltage IVC is not maintained constant when the external voltage Vcc is varied or when the extent of the operating power source is wide.
FIG. 3 is a graph illustrating an initial operating characteristic of the conventional internal voltage generating circuit of FIGS. 1 and 2, and indicated generally by the reference numeral 30. The internal voltage IVC has a characteristic that is increased according to the external voltage Vcc until an initial certain specific voltage, and at a setting voltage, tends to maintain a constant and stable voltage level independent of increment of the external voltage Vcc. In FIG. 3, the horizontal axis represents the external voltage while the longitudinal axis represents the internal voltage. The conventional internal voltage generating circuit, however, generates the internal voltage IVC having a certain variation gradient compared with an ideal internal voltage CVC that is uniform at a setting voltage. In addition, since the internal voltage driver 20 includes a transistor and a resistor, the internal voltage IVC generated from the conventional internal voltage generating circuit has a certain variation gradient that is substantially proportional to the external voltage Vcc.
Accordingly, the conventional internal voltage generating circuits suffer from the following problems and disadvantages: 1. When the external voltage is fluctuated, the reference voltage generated from the reference voltage generator is changed according to the external voltage, which also increases the variation gradient of the internal voltage that follows the reference voltage. Thus, the internal voltage acts as noise in the internal circuits of the semiconductor device requiring a stabilized power source, thereby causing a part of the circuit to be out of order and/or shortening the service life of the circuit.


The hierarchy of the hyphenation points in a word is considered and the amount of space remaining in the line where the hyphenated word is to fit is determined, thus selecting the best hyphenation point for the word. Instead of selecting the last possible hyphen within the hot zone, the hot zone is scanned to find hyphenation points that may be better than the last hyphen within the hot zone. The higher a hyphenation point is in the hierarchy, the more preferred is the hyphen.

1. Technical Field
The invention disclosed broadly relates to computer methods, and particularly relates to a computer method for choosing hyphenation points in multilingual text.
2. Background Art
Mechanized hyphenation is a process that is necessary for computerized word processing and printing applications. Mechanized hyphenation has been attempted by the use of stored dictionary systems, rule-based systems, and statistical systems. Dictionary-based systems store the hyphenation for each dictionary entry. Rule-based systems use rules that may apply to more than one word. Rules may be non-specific and apply to any word, or they may be associated with specific words to provide their hyphenation points. Finally, the statistical systems use tables of hyphenation statistics based on a collection of words and apply these statistics to determine the hyphenation of other words. Some of these statistical techniques insert numbers within a word to be hyphenated that indicate the confidence with which the word can be hyphenated at that particular point.
Carlgren describes a system that combines several techniques in IBM Technical Disclosure Bulletin, Vol. 26, No. 11, pp. 6108-6109 and pp. 6095-6096. Carlgren elaborates on the combination of dictionary-based hyphenation and rule-based hyphenation in U.S. Pat. No. 4,574,363. Rosenbaum describes dictionary-based methods of hyphenation in U.S. Pat. Nos. 4,028,677 and 4,092,729. Herzik also describes a dictionary-based method for hyphenating multilingual text in U.S. Pat. No. 4,456,969. Zamora describes a rule-based method (IBM patent application Ser. No. 344,344 entitled "Computer Method for Executing Transformation Rules") for hyphenating text.
Another prior art technique by Moore in the IBM Technical Disclosure Bulletin, Vol. 29, No. 1, pp. 383-384 combines manual selection of hyphenation points and dictionary hyphenation.

Computer method for ranked hyphenation of multilingual text

International Business Machines Corporation


Therapeutic devices that provide support or pressure to tissue. Devices contain a material that is capable of being contracted from its relaxed state to an evacuated state. The material applies pressure to the tissue of a patient when the material is in its relaxed state. Reduction of pressure by application of a vacuum results in a contracted state of the device, so that the device can be applied or delivered to a patient. Release of vacuum results in a return to the relaxed state, thus providing a maximum desirable pressure to tissue and avoiding the possibility of over-pressure which can result in tissue damage or necrosis.

Patients suffering from injury or disease or recovering from surgery may be treated by the application of constant or intermittent pressure. Pressure is used to control swelling, increase blood flow, and immobilize tissue.
In cases of acute injuries, such as acute joint injury, three treatments are employed simultaneously. First, the injured region is chilled (such as with ice); second, pressure is applied using an elastic bandage; and third, immobilization is achieved using a splint. For example, an athletic trainer applies elastic wrap to an injured ankle or knee and then immobilizes the joint with a splint or bulky bandage. However, the application of elastic wrap may produce a wide range of pressures on the injured limb. The incorrect pressure may retard venous or arterial circulation and may contribute to thromboembolism; pressure that is too high can induce tissue ischemia that further injures the tissue.
More complex pressure devices are available to patients suffering from various venous, circulatory and peripheral vascular diseases. These devices typically consist of an inflatable bladder in the form of a sleeve that can be placed around all or a portion of a patient's arm or leg. The bladder is connected to a pump that alternately inflates and deflates the bladder. In some such devices, the sleeve placed around the extremity includes a number of sequential bladders along the axial length of the sleeve to allow the sleeve to be inflated and deflated in a peristaltic manner along its length. By alternately inflating and deflating the bladder or bladders contained within the sleeve, circumferential pressure is applied to the patient's extremity, thus aiding in the circulation of blood there through. Such systems are currently used to treat venous insufficiency, prevent deep venous thrombus and control lymphedema and improve tissue perfusion in patients with peripheral arterial disease.
Other medical devices such as catheters and tracheotomy tubes are placed into a body lumen and then held in place with an inflatable balloon at the distal end of the device. The balloon is subject to over-inflation, however, again resulting in possible damage to treated tissue.
In addition, current systems tend to be expensive and complex, frequently being coupled to feedback circuits to control changes in pressure. Compression systems have been known to malfunction and cause undesirable variability in or increase in the applied pressure. Even when such systems are controlled by the patient, they may be subject to incorrect operation resulting in over-inflation of the sleeve. For such a system used to correct venous insufficiency in a limb, for example, incorrect operation is at best painful and at worst results in loss of the limb. Finally, most patients complain of some level of pain during inflation due to the rapid increase in pressure against the extremity.
In view of the above, the need exists for therapeutic devices that are capable of applying pressure but which are unable to produce over-pressure at the site of damage or disease. Such devices should be simple to use, allow peristaltic pumping at a variety of pressures, and have the ability to apply heat or cold.


A code division multiple access (CDMA) communication system using spread spectrum signaling over a communication bandwidth uses two different signal spectra generated using two different respective spreading code formats, such as NRZ code formatting and Manchester code formatting, for respectively providing nonsplit spectra having a center peak and split spectra having a center null. The spectra are combined during transmission as a CDMA communication signal having a composite spectrum. The use of different code formats produces the composite spectrum of respective center peak and center null spectra that enables increased channel capacity.

Code division multiple access (CDMA) communications have been used for some time. Typically, transmitted data is formatted and the spectrum is spread using CDMA spreading codes for communicating CDMA spread spectrum communication signals between a transmitter and a plurality of receivers within a null-to-null communications bandwidth. A transmitted signal includes superimposed spread spectrum signals spread by respective spreading codes for providing code division access to multiple receivers. Differing spreading codes provide signal code division multiplexing for enabling the respective receivers to acquire particular respective communication spread spectrum signals among all of the transmitted spread spectrum signals of the transmitted signal. The CDMA communication systems use a particular digital format to format a data stream prior to spectrum spreading and prior to transmission. The digital format is also applied to the spreading codes prior to spreading formatted data. One such digital format is the nonreturn to zero (NRZ) format. Another format is the Manchester format, also known as biphase-L. In an NRZ CDMA communication system, an NRZ format is used to format separate data streams into NRZ formatted data streams that are then spectrum spread by respective NRZ formatted CDMA spreading codes for transmission to respective receivers. The communication spectrum of an NRZ formatted and spread spectrum CDMA signal is characterized as having a center peak in the communications bandwidth. The communication spectrum is also referred to as a nonsplit spectrum. In a Manchester CDMA communication system, a Manchester format is used to format many separate data streams into Manchester formatted data streams that are then spectrum spread by respective Manchester formatted CDMA spreading codes for transmission to respective receivers. The communication spectrum of a Manchester formatted and spectrum spread CDMA signal is characterized as having a bandwidth center null of the communications bandwidth. This spectrum is also known as a split spectrum.
Typically, a CDMA system using NRZ formatting has a peak power spectral density at the center of the frequency band and is characterized as a nonsplit spectrum signal. A CDMA system using Manchester code formatting has a power spectral density null at the center of the frequency band and is characterized as a split spectrum signal. Another available digital format is the binary offset carrier format that also provides a split spectrum of a spread spectrum communication CDMS signal. The binary offset carrier format is a general case of the Manchester format. Conventional CDMA communication systems typically use NRZ code formatting. However, CDMA communication systems can also be implemented using a split spectrum code format, such as the Manchester code digital format and the binary offset carrier digital format.
An NRZ CDMA communication system may, for example, have an available bandwidth of 200 kHz and have a data rate of 400 bps. The spreading code chipping rate for the CDMA may be set at 100 kHz so that the null-to-null bandwidth for the spectrum spread CDMA signal is 200 kHz with a center peak. Channel capacity is the number of communication channels, that is, spread spectrum signals, which can be communicated within a given bandwidth. Using NRZ formatting, the channel capacity is about thirty-eight at a BER of 10−5. With the same signaling conditions, Manchester formatting and binary offset carrier digital formatting also provide about the same channel capacity. Channel capacity is a valuable resource. Increasing the channel capacity increases the number of users that can be served by a CDMA communication system. The NRZ, Manchester, and binary offset carrier formatted CDMA communication systems have severely limited channel capacities. These and other disadvantages are solved or reduced using the invention.

Code division multiple access enhanced capacity system