Abstract: Some embodiments of the present invention provide techniques and systems for determining whether a high-level model (HLM) for a circuit design is equivalent to a register-transfer-level (RTL) model for the circuit design. During operation, a system can identify a set of checkpoints. Each checkpoint can be associated with a characteristic function defined over the states of a finite-state-machine (FSM) representation of the HLM, a characteristic function defined over the states of an FSM representation of the RTL model, and an invariant defined over a set of variables in the HLM and a set of registers in the RTL model. Next, the system can generate a set of invariant proof problems, wherein each invariant proof problem corresponds to a transition between two checkpoints in the set of checkpoints. The system can then determine whether the HLM is equivalent to the RTL model by solving the set of invariant proof problems.

Abstract: A receiver circuit is described. In the receiver circuit, an analog-to-digital converter (ADC) generates first samples of a data signal based on a first clock signal, and a clock-data-recovery (CDR) error-detection circuit generates second samples of the data signal based on a second clock signal. In addition, the CDR error-detection circuit estimates intersymbol interference (ISI) at a current sample in the second samples from an adjacent, subsequent sample in the second samples. Based on the second samples and the estimated ISI, a CDR circuit generates the first clock signal and the second clock signal, which involves modifying the skews of either or both of these clock signals so that the current sample is associated with a zero crossing of a pulse response of a communication channel from which the data signal was received, thereby reducing or eliminating the ISI from the adjacent, subsequent sample.

Abstract: One embodiment of the present invention provides an integrated circuit chip, including an active face upon which active circuitry and signal pads reside, and a back face opposite the active face. The integrated circuit chip additionally comprises an electromagnetic via that facilitates communication between signal pads on the integrated circuit chip and signal pads on a second integrated circuit chip. The electromagnetic via couples a signal pad on the active face of the integrated circuit chip to the back face of the integrated circuit chip so that the integrated circuit chip can communicate with the second integrated circuit chip while the back face of the integrated circuit chip is adjacent to the active face of the second integrated circuit chip. Moreover, the electromagnetic via operates by facilitating non-conductive signaling through the integrated circuit chip.

Abstract: A system that activates a muscle to produce a functional movement in a subject through electrical stimulation is described. During operation, the system first obtains a non-isometric model which defines a functional movement associated with the muscle in response to electrical stimulation of the muscle. Next, the system uses the non-isometric model to compute an electrical stimulation which produces a desired functional movement in the subject. The system then applies the computed electrical stimulation to the muscle to produce the desired functional movement in the subject.

Abstract: An integrated circuit containing a communication channel is described. This communication channel includes a transmit circuit configured to transmit signals using a voltage-mode driver, a receive circuit, and a capacitive link that couples the transmit circuit to the receive circuit. The communication channel includes a filter with a capacitive-summing junction to equalize signals communicated between the transmit circuit and the receive circuit.

Abstract: One embodiment of the present invention provides a system that facilitates adjusting the wavelengths of lasers via temperature control. This system includes a chip with an active face upon which active circuitry and signal pads reside. A thermal-control mechanism provides localized thermal control of two lasers mounted upon the active face of the chip. By individually controlling the temperature of the lasers, the thermal-control mechanism controls the wavelengths emitted by each respective laser. By creating a temperature gradient that causes a temperature difference between two or more lasers, the system can cause the lasers to emit different wavelengths.

Abstract: Circuits and methods for providing zero-gap playback of consecutive data streams in portable electronic devices, such as media players, are described. In some embodiments, a circuit includes a decoder circuit configured to receive encoded audio data and to output decoded audio data including data streams associated with a data file and a subsequent data file. Moreover, a predictive circuit, which is electrically coupled to the decoder circuit, is configured to selectively generate additional samples based on samples in the data file, where the additional samples correspond to times after the end of a data stream associated with the data file. Additionally, a filter circuit, which is electrically coupled to the decoder circuit and selectively electrically coupled to the predictive circuit, is configured to selectively combine or blend samples at a beginning of the subsequent data file with the additional samples. Note that the circuit may be included in an integrated circuit.

Abstract: One embodiment provides a method for determining mask layouts. During operation, the system can receive a design intent. Next, the system can determine a set of critical edges in the design layout, and select a first edge and a second edge. The system can then determine a first trench and a second trench using the first edge and the second edge, respectively. Note that an edge of the first trench may substantially overlap with the first edge, and an edge of the second trench may substantially overlap with the second edge. Next, the system may assign the first trench and the second trench to the first mask layout and the second mask layout, respectively. The system can then increase the first trench and the second trench, thereby improving pattern fidelity. The resulting mask layouts may be used in a double patterning process.

Abstract: One embodiment of the present invention provides a system that facilitates secure single sign-on (SSO) authentication for web-services communications. During operation, the system receives a Web Services for Remote Portlet (WSRP) request from a WSRP consumer and also receives a digital signature associated with the WSRP request. The system then validates the digital signature and authenticates a user based on the validation, thereby allowing the user to sign on without providing a password.

Abstract: A system and method are provided for conducting a client-server application (e.g., instant messaging, VoIP telephony) using non-persistent communications. Clients issue periodic heartbeat messages to a connectionless server using a non-persistent (e.g., UDP) communication protocol. The heartbeat messages identify the clients by unique client identifiers. When an application server has an unsolicited communication for a client (e.g., a new instant message, a VoIP call), the application server retrieves the client's address from the connectionless server if it does not already have the address. The application server forwards the unsolicited communication to the client via a non-persistent communication, and may spoof the connectionless server if necessary to reach the client through a firewall, proxy, NAT or similar entity. Clients that cannot use non-persistent protocols establish persistent connections with a client manager.

Abstract: A sensing system includes a set of sensors and a data-fusing mechanism coupled to at least one of these sensors. In the set of sensors, at least one sensor is configured to store one or more measurement models for one or more phenomenon states. Furthermore, at least one sensor in the set of sensors is configured to sample a measurement value and generate a likelihood function based on the sampled measurement and the measurement models. The data-fusing mechanism coupled to a respective sensor in the set of sensors is configured to collect one or more likelihood functions generated by the one or more sensors and use the collected likelihood functions to compute an aggregate probability of a phenomenon state.

Abstract: A controller operable to control an array of processing elements comprises a retrieval unit operable to retrieve instruction items for each of a plurality of instructions streams, each instruction stream having a plurality of instructions items, a combining unit operable to combine the plurality of instruction streams into a serial instruction stream, and a distribution unit operable to distribute the serial instruction stream to an array of processing elements.

Abstract: A system and method for emulating the input/output performance of an application. A workload description language is used to produce a small but accurate model of the application, which is flexible enough to emulate the application's performance with varying underlying system configurations or operating parameters. The model describes I/O operations performed by the application, and reflects any dependencies that exist between different application threads or processes. The model is then executed or interpreted with a particular system configuration, and various parameters of the I/O operations may be set at the model's run-time. During execution, the input/output operations described in the model are generated according to the specified parameters, and are performed. The system configuration and/or I/O operation parameters may be altered and the model may be re-run.

Abstract: In order to provide filtering of clock noise from an integrated circuit at least one differential signal line connected to the integrated circuit is provided with an embedded common mode filter. The common mode filter can be provided in the form of a hollowed out portion of an impedance reference plane.

Abstract: An embodiment provides systems and techniques for determining a process model. During operation, the system may receive a first optical model which models a first optical system of a photolithography process. Next, the system may use the first optical model to determine a second optical model that models a second latent image that is formed by the first optical system at a second distance. The system may also use the first optical model to determine a third optical model that models a third latent image that is formed by the first optical system at a third distance. Next, the system may receive process data which is obtained by subjecting a test layout to the photolithography process. The system may then determine a process model using the first optical model, the second optical model, the third optical model, the test layout, and the process data.

Abstract: One embodiment of the present invention provides a system that parallelizes the TCP-related actions of a network connection between two computer systems during a data transfer between the two computer systems. During operation, the first computer system partitions the data into two or more data segments, and assigns the data segments to multiple processing elements. These multiple processing elements subsequently prepare and send their assigned data segments to the second computer system in parallel using TCP.

Abstract: One embodiment of the present invention provides a system and a method for performing a page-table lookup in a manner that supports adaptive page sizes. During operation, the system receives a virtual address. Next, the system looks up this virtual address in a page table. Since each entry in the page table maintains a page size, the lookup process involves using the page size to determine the number of bits that must be compared to find a matching page table entry. A page table entry matches the virtual address if the determined number of bits in the virtual address match the virtual address in the page table entry. If a matching page table entry is found, the system returns the physical page address from the matching page table entry.

Abstract: Embodiments of the present invention provide a system that executes a branch instruction. When executing the branch instruction, the system obtains a stored prediction of a resolution of the branch instruction and fetches subsequent instructions for execution based on the predicted resolution of the branch instruction. If an actual resolution of the branch instruction is different from the predicted resolution (i.e., if the branch is mispredicted), the system updates the stored prediction of the resolution of the branch instruction to the actual resolution of the branch instruction. The system then re-executes the branch instruction. When re-executing the branch instruction, the system obtains the stored prediction of the resolution of the branch instruction and fetches subsequent instructions for execution based on the predicted resolution of the branch instruction.

Abstract: A system which regulates communication with a server is described. During operation, the system determines a retransmission rate of data packets during a first set of conversations between a group of users and the server via a peering link. Next, the system compares the retransmission rate and an historical retransmission rate of data packets during a second set of conversations between a second group of users and the server via the peering link. The system then adjusts a target acceptance rate of the server to requests to initiate conversations with additional users via the peering link based on the comparison of the retransmission rate and the historical retransmission rate. Additionally, the system accepts or rejects a request to initiate a conversation between another user and the server via the peering link based on an actual acceptance rate of the server to requests to initiate the conversations and the target acceptance rate.

Abstract: One embodiment of the present invention provides a system that facilitates warning of collision between a primary principal and one or more non-primary principals. The system includes a triggering mechanism and a preliminary assessment mechanism. During operation, the triggering mechanism determines whether a trigger condition is met based on the state of the primary principal. When the trigger condition is met, the preliminary assessment mechanism generates one or more collision scenarios associated with the trigger condition, assesses a preliminary probability of collision in a collision scenario, and, based on the preliminary probability of collision in the collision scenario, activates a specialized assessment mechanism to assess a refined probability of collision in the collision scenario.