Patents by Inventor Wai Chen

Wai Chen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7720026
    Abstract: A method for organizing and maintaining an ad-hoc network for communication between a plurality of moving devices is disclosed. The method comprises the steps of grouping the plurality of moving devices into at least one local peer group (LPG), ordering the plurality of devices within each LPG based upon a relative position of each of the plurality of devices within each LPG and assigning a unique identifier for each of the plurality of moving devices, where the unique identifier is based, in part on the LPG that the corresponding moving device is located.
    Type: Grant
    Filed: January 11, 2006
    Date of Patent: May 18, 2010
    Assignees: Telcordia Technologies, Inc., Toyota Infotechnology Center, U.S.A., Inc.
    Inventors: Wai Chen, Jasmine Chennikara-Varghese, Marcus Pang, Toshiro Hikita, John Lee, Shengwei Cai
  • Patent number: 7713674
    Abstract: An emulsion polymerization process comprising polymerizing monomer in an emulsion in a reaction vessel at a first temperature to form a resin; cooling the reaction vessel to a second temperature that is above the softening point of the resin yet below the temperature required for significant depolymerization reaction to occur; and adding water to the cooled reaction vessel in an amount sufficient to effect phase inversion with mixing for a sufficient time to form an aqueous latex emulsion in the absence of a surfactant.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: May 11, 2010
    Assignee: Xerox Corporation
    Inventors: Allan Kwok-Wai Chen, Milan Maric, Tie Hwee Ng, George Liebermann, Enno Eric Agur, Hadi Khan Mahabadi
  • Publication number: 20100074114
    Abstract: A method for high rate data delivery in a multi-hop vehicular network comprises at each source vehicle, initiating a packet having a flow tag, assigning an identifier of the content and the current location to the flow tag, and forwarding the packet; at each destination vehicle, setting a flow request and broadcasting at the current intersection; further on movement, setting the flow request at the new intersection, and at each intersection, selecting a header vehicle at the intersection, computing backlog and congestion indicators and listening for broadcasts with a matrix and the flow requests at the header vehicle, determining if the matrix is present, updating the matrix in accordance with the backlog and congestion indicators if the matrix is present, initializing the matrix and estimating the delay on the outgoing road segments if the matrix is not present, forwarding the packet flow, and broadcasting the matrix from the header vehicle.
    Type: Application
    Filed: September 21, 2009
    Publication date: March 25, 2010
    Applicant: TELCORDIA TECHNOLOGIES, INC.
    Inventors: Ratul K. Guha, Wai Chen, Jasmine Chennikara-Varghese, Stephanie Demers
  • Publication number: 20090310608
    Abstract: The present invention offers systems and methods for effective multiple-hop routing, multicasting and media access control for vehicle group communications that employ directional wireless radio technology. Multi-beam optic-wireless media and streamlined operations provide low-overhead communications among vehicles. Systems and methods are provided to maintain a quasi-stationary group of neighboring vehicles, enable high-throughput on-demand switching among multiple vehicles, enable group coding in the vehicle group to achieve higher throughput, and enable dynamic adjustment of link to maintain desirable vehicle group. The proposed solution builds upon the conception of a MAC-free wireless operation and quasi-stationary vehicular switched network to achieve ultra-low-overhead and high-throughput vehicle communications.
    Type: Application
    Filed: July 23, 2008
    Publication date: December 17, 2009
    Applicants: TELCORDIA TECHNOLOGIES, INC., TOYOTA INFOTECHNOLOGY CENTER U.S.A., INC.
    Inventors: Wai Chen, John Lee, Ratul K. Guha, Ryokichi Onishi, Rama Vuyyuru
  • Publication number: 20090285197
    Abstract: The present invention provides methods for efficient control message distribution in a VANET. Efficient flooding mechanisms are provided to fulfill the objective of flooding (delivering a message to every connected node) with a limited number of re-broadcasting by selected key nodes. A suppression-based efficient flooding mechanism utilizes a Light Suppression (LS) technique to reduce the number of flooding relays by giving up the broadcasting of a flooding message when a node observes downstream relay of the same flooding message. Additionally, a relay-node based efficient flooding mechanism selects Relay Nodes (RN) to form an efficient flooding tree for control message delivery. RNs are nodes that relay at least one control message, for instance a Membership Report (MR) to the upstream node in “k” previous control message cycles The upstream node may be the group header (GH) for the LPG.
    Type: Application
    Filed: May 14, 2008
    Publication date: November 19, 2009
    Applicants: Telcordia Technologies, Inc., Toyota InfoTechnology Center USA
    Inventors: Wai Chen, Taek Jin Kwon, John Lee, Ryokichi Onishi, Toshiro Hikita
  • Publication number: 20090285213
    Abstract: An on-demand method of routing data between a plurality of local peer groups (LPG). Each LPG includes a plurality of moving nodes. The method comprises transmitting a route request message from a source node, relaying the route request message to a native boundary node; forwarding the route request message to a foreign boundary node, determining if the destination node is within an LPG for the foreign boundary node; relaying the route request message to another boundary node if the destination node is not within the LPG, relaying the route request message to the destination node if the destination node is within the LPG, receiving the routing request message at the destination node, transmitting a routing response to the source node, relaying the routing response to the source node through a path discovered by the route request, receiving the routing response at the source node, and transmitting the data, upon receipt of the routing response.
    Type: Application
    Filed: May 15, 2008
    Publication date: November 19, 2009
    Applicants: TELCORDIA TECHNOLOGIES, INC., TOYOTA INFO TECHNOLOGY CENTER USA
    Inventors: Wai Chen, Marcus Pang, Taek Jin Kwon, Ryokichi Onishi, Toshiro Hikita
  • Patent number: 7620687
    Abstract: A plurality of servers for processing client requests forward the requests among themselves to achieve a balanced load. When a server initially receives a client request, it randomly selects another of the plurality of servers, referred to as a first-chance server, and forwards the request to this server. Upon receiving the request, the first-chance server determines if it is overloaded and if not, processes the request. However, if overloaded, the first-chance server compares its load to the load of one or more predetermined next-neighbor servers. If the next-neighbor server(s) are more loaded than the first-chance server, the first-chance server processes the request. Otherwise, the first-chance server forwards the request to the least loaded next-neighbor server. The next-neighbor receiving the request either processes it directly, or alternatively, based on its current load and that of its next-neighbor server(s), forwards the request to another next-neighbor server for processing.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: November 17, 2009
    Assignees: Telcordia Technologies, Inc., Toyota Motor Corporation
    Inventors: Chung-Min Chen, Wai Chen, Yibei Ling, Marcus Pang, Shengwei Cai
  • Publication number: 20090238187
    Abstract: An inventive method for data delivery in a multi-hop vehicular network with multiple vehicles and intersections is presented. The method comprises, at each source vehicle, initiating packet flow, labeling packets with destination coordinates and a current location, and forwarding the packet flow, and at each intersection, selecting a header vehicle, computing a backlog indicator and listening for broadcasts with a matrix and delay information, updating the matrix in accordance with the backlog indicator if the matrix is present, otherwise initializing the matrix, forwarding the packet flow, and broadcasting the matrix from the header vehicle. In one embodiment, selection of the header vehicle is performed based on random countdown and vehicle ID. The method converges to the optimal (lowest latency) state irrespective of the initial starting point of the network and continues to tend towards the optimal state even as the network conditions alter.
    Type: Application
    Filed: March 20, 2009
    Publication date: September 24, 2009
    Applicant: TELCORDIA TECHNOLOGIES, INC.
    Inventors: Ratul K. Guha, Wai Chen, Jasmine Chennikara-Varghese, Stephanie Demers
  • Publication number: 20090201928
    Abstract: A method for routing a multicast message comprising the steps of receiving a multicast message including at least a message, a source identifier, a sequence number, a time-to-live value and a multicast group destination, determining if the multicast group destination is in a multicast forwarding table, determining if the message has been previously received, adding the multicast message to the multicast forwarding table if it is determined that the multicast message has not been previously received, determining if a node that received the multicast message is a forwarding node; randomly setting a wait time for forwarding the multicast message; and forwarding the multicast message at the expiration of the wait time.
    Type: Application
    Filed: February 13, 2008
    Publication date: August 13, 2009
    Inventors: Wai Chen, John Lee, Ryokichi Onishi, Toshiro Hikin
  • Patent number: 7567809
    Abstract: Wireless internet in the in-vehicle environment is an evolving reality that reflects the gradual convergence of wireless and internet technologies. The present invention provides an application layer system that makes wireless internet access adaptive to dynamically changing heterogeneous network environments, by stressing carrier-independence and access transparency. To achieve these objectives, the present invention provides the following features: HTTP session continuity and automatic HTTP failure recovery; network environment awareness and application-level preemptive handoff based on bandwidth capacity.
    Type: Grant
    Filed: March 20, 2006
    Date of Patent: July 28, 2009
    Assignees: Telcordia Technologies, Inc., Toyota Motor Corporation
    Inventors: Yibei Ling, Wai Chen, Onur Altintas
  • Patent number: 7546082
    Abstract: As multicast services become prevalent, it is important to find viable solutions for multicasting to mobile nodes. This problem is complicated by the necessity to support multicast services over existing backbone and access networks that may have varying network and/or link layer multicasting capabilities. While most work on supporting multicast services focuses on the IP layer solution, the present invention presents an application-layer approach for providing multicast services to mobile users traversing networks with diverse multicast capabilities. The present invention places multicast proxies in the backbone and access networks to support several multicast-related functions at the application layer including the creation of virtual networks for dynamically tunneling through non-multicast-capable networks.
    Type: Grant
    Filed: March 2, 2004
    Date of Patent: June 9, 2009
    Assignees: Telcordia Technologies, Inc., Toyota Motor Corporation
    Inventors: Jasmine Chennikara, Wai Chen, Ashutosh Dutta, Onur Altintas
  • Publication number: 20090129323
    Abstract: A method for determining a transmission channel for multi-hop transmission of a data packet from a plurality of data channels in an ad-hoc network. The network includes at least one local peer group. Each local peer group has a plurality of moving vehicles as nodes. The method comprises steps of determining available channels for data packet transmission at each node, transmitting a first list of available channels to at least one other node, receiving, from the at least one other node, a second list of available channel for the at least one other node, creating an available channel table including the first and second lists of available channels, selecting a transmitting channel for a data packet based upon information in the available channel table, and advertising the selected channel to the at least one other node.
    Type: Application
    Filed: November 19, 2007
    Publication date: May 21, 2009
    Inventors: Wai Chen, Jasmine Chennikara-Varghese, Marcus Pang, Ryokichi Onishi, Toshiro Hikita
  • Publication number: 20090122738
    Abstract: A method for distributing a packet to a plurality of moving nodes comprising receiving a packet containing at least a message, a sender identifier, a location of a sender, an identifier for a relay node and distance from the sender and the relay node, determining if a node receiving the packet is the relay node and immediately distributing the packet to a plurality of moving nodes if the receiving node is the relay node. If the receiving node is not the relay node, the method further comprises steps of waiting a set period of time, determining if a packet is received from a different sender containing the same message, within the period of time and distributing the packet to a plurality of moving nodes if a packet containing the same message is not received within the period of time. The distributed packet includes an identifier for a successive relay node.
    Type: Application
    Filed: November 13, 2007
    Publication date: May 14, 2009
    Inventors: Wai Chen, Stephanie Demers, John Lee, Marcus Pang, Ryokichi Onishi, Toshiro Hikita
  • Publication number: 20090052320
    Abstract: The present invention presents an architecture to dynamically measure and estimate the throughput perceived by a user during a connection in real-time in a wireless network system. The architecture system design of the present invention allows for information gathering independent of the mathematical models used and takes into account security settings in the network hosts. The present invention also sets forth a number of throughput estimators (TEs) that can be used within the architecture to gather the information needed to carry out the throughput estimation calculations. The throughput estimations can then be used for download rate control, QoS, load balancing, etc. The present invention also provides algorithms to calculate the real-time throughput experienced by a user flow.
    Type: Application
    Filed: October 21, 2008
    Publication date: February 26, 2009
    Inventors: Yibei Ling, Jasmine Chennikara, Wai Chen, Onur Altintas
  • Patent number: 7477602
    Abstract: The present invention presents an architecture to dynamically measure and estimate the throughput perceived by a user during a connection in real-time in a wireless network system. The architecture system design of the present invention allows for information gathering independent of the mathematical models used and takes into account security settings in the network hosts. The present invention also sets forth a number of throughput estimators (TEs) that can be used within the architecture to gather the information needed to carry out the throughput estimation calculations. The throughput estimations can then be used for download rate control, QoS, load balancing, etc. The present invention also provides algorithms to calculate the real-time throughput experienced by a user flow.
    Type: Grant
    Filed: April 1, 2004
    Date of Patent: January 13, 2009
    Assignees: Telcordia Technologies, Inc., Toyota Infotechnology Center, U.S.A., Inc.
    Inventors: Yibei Ling, Jasmine Chennikara, Wai Chen, Onur Altintas
  • Publication number: 20080279141
    Abstract: A communications path is established among an ordered sequence of moving nodes, representing vehicles. Available channels may differ from one node to the next node and a node cannot use the same channel for both receiving and transmitting information. Three methods are described that provide an optimal sequence of channel assignments between the nodes. A sequence of channel assignments is called optimal if it establishes a communications path from the first node in the sequence to the last node in the sequence, or, if such a path does not exist, from the first node to the farthest node possible in the sequence. The first method uses a depth-first search starting from the first node in the sequence. The second method uses a “look ahead” scheme in the depth-first search method. The third method requires only a single pass through the sequence of nodes by identifying optimal channel assignments in subsequences of nodes without a need for backtracking.
    Type: Application
    Filed: May 8, 2007
    Publication date: November 13, 2008
    Inventors: Hanan Luss, Wai Chen, Toshiro Hikita, Ryokichi Onishi
  • Publication number: 20080184464
    Abstract: A helmet includes a windscreen with a housing for holding a windscreen wiper device being positioned in a chin portion of the helmet. A motive power fitting is provided for a windscreen wiper head and a windscreen wiper rod. The motive power fitting is fixed inside a casing. The windscreen wiper rod coordinates with a fixing axle with one side of the windscreen wiper rod being connected to the conveying portion of the motive power and the other side of the windscreen wiper rod being connected to the windscreen wiper head. The windscreen wiper device on the windscreen wiper head is tightly fixed on the protection windscreen on the protection helmet. The windscreen wiper device includes a power supply with the output being connected to the motive power device. The helmet may be used by a driver on a rainy or foggy day for increasing safety during such weather.
    Type: Application
    Filed: February 5, 2008
    Publication date: August 7, 2008
    Inventor: Ka Wai Chen
  • Publication number: 20080095163
    Abstract: A method and communication device for routing unicast and multicast messages. The method for routing a unicast message includes receiving a first control packet including routing parameters from a group header node, updating a routing table based upon the routing parameters, receiving a second control packet including additional routing parameters from a group node, updating the routing table based upon the additional routing parameters and generating a forwarding table from the routing table when both of the updated steps are completed. The unicast message is routed based upon the forwarding table. A method for routing a multicast message comprises receiving the multicast message, determining if a multicast group destination for the multicast message is in a multicast forwarding table (MFT), determining if the multicast message has been previously forwarded and forwarding the multicast message if the message was not previously forwarded and the multicast group destination is in the MFT.
    Type: Application
    Filed: October 23, 2006
    Publication date: April 24, 2008
    Inventors: Wai Chen, Taek-Jin Kwon, Toshiro Hikita, Ryokichi Onishi, John Lee
  • Publication number: 20080095134
    Abstract: An ad-hoc wireless network with a roadside network unit (RSU) and a local peer group (LPG). The LPG is formed from a plurality of moving vehicles. The LPG includes a group header node (GH) for managing the LPG. The GH is elected from one of the moving vehicles. The LPG further includes group nodes (GN) designated from the remaining moving vehicles in a given area. Each of the moving vehicles, whether the GH or the GN, communicates with other using routing paths created based upon a first control packet broadcast from the GH and a second control packet broadcast from each of the GN. Each moving vehicle communicates with the RSU using a routing paths created based upon a beacon broadcast by the RSU and a reply signal from each of the moving vehicles. The RSU can also be a member of the LPG and act as GN or GH.
    Type: Application
    Filed: October 23, 2006
    Publication date: April 24, 2008
    Inventors: Wai Chen, Marcus Pang, Jasmine Chennikara-Varghese, John Lee, Toshiro Hikita, Ryokichi Onishi, Taek-Jin Kwon
  • Publication number: 20080061375
    Abstract: A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. In one embodiment the family includes a 5V CMOS pair, a 12V CMOS pair, a 5V NPN, a 5V PNP, several forms of a lateral trench MOSFET, and a 30V lateral N-channel DMOS. Each of the devices is extremely compact, both laterally and vertically, and can be fully isolated from all other devices in the substrate.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 13, 2008
    Applicant: Advanced Analogic Technologies, Inc.
    Inventors: Richard Williams, Michael Cornell, Wai Chen