Abstract: Distributed transmit beamforming is a form of cooperative communication in which two or more information sources simultaneously transmit a common message and control the phase of their transmissions so that the signals constructively combine at an intended destination. Depending on the design objectives and constraints, the power gains of distributed beamforming can be translated into dramatic increases in range, rate, or energy efficiency. Distributed beamforming may also provide benefits in terms of security and interference reduction since less transmit power is scattered in unintended directions. Key challenges in realizing these benefits, however, include coordinating the sources for information sharing and timing synchronization and, most crucially, distributed carrier synchronization so that the transmissions combine constructively at the destination. This article reviews promising recent results in architectures, algorithms, and working prototypes which indicate that these challenges can be surmounted. Directions for future research needed to translate the potential of distributed beamforming into practice are also discussed.

Abstract: Aspects of the invention provide for information to be synchronized in an asynchronous manner among two or more computing devices.

Abstract: This paper presents a unified synchronization framework with application to precision formation flying spacecraft. Central to the proposed innovation, in applying synchronization to both translational and rotational dynamics in the Lagrangian form, is the use of the distributed stability and performance analysis tool, called contraction analysis that yields exact nonlinear stability proofs. The proposed decentralized tracking control law synchronizes the attitude of an arbitrary number of spacecraft into a common time-varying trajectory with global exponential convergence. Moreover, a decentralized translational tracking control law based on oscillator phase synchronization is presented, thus enabling coupled translational and rotational maneuvers. Although the translational dynamics can be adequately controlled by linear control laws, the proposed method permits highly nonlinear systems with nonlinearly coupled inertia matrices such as the attitude dynamics of spacecraft whose large and rapid slew maneuvers justify the nonlinear control approach. The proposed method integrates both the trajectory tracking and synchronization problems in a single control framework.

Abstract: Multiprocessor architectures and platforms have been introduced to extend the applicability of Moore’s law. They depend on concurrency and synchronization in both software and hardware to enhance the design productivity and system performance. These platforms will also have to incorporate highly scalable, reusable, predictable, cost- and energy-efficient architectures. With the rapidly approaching billion transistors era, some of the main problems in deep sub-micron technologies which are characterized by gate lengths in the range of 60-90 nm, will arise from non-scalable wire delays, errors in signal integrity and unsynchronized communications. These problems may be overcome by the use of Network on Chip (NOC) architecture. In this paper, we have summarized over sixty research papers and contributions in NOC area.

Abstract: Systems, software, and apparatuses that provide wired and wireless telecommunications under conditions where signal strength is poor or intermittent, the coordination and synchronization of data and workflows across various communication links under such conditions, especially intermittent or unreliable communications links, and the management of wireless mobile applications in such environments. The present invention technology herein relates to the fields of computer science, telecommunications, and data management.

Abstract: Increasing evidence suggests that neuronal synchronization in the gamma band (30-100 Hz) may play an important role in mediating cognitive processes. Gamma-band synchronization provides for the optimal temporal relationship between two signals to produce the long-term synaptic changes that have been theorized to underlie memory formation. Although neuronal populations in the hippocampus oscillate in the gamma range, the role of these oscillations in memory formation is still unclear. To address this issue, we recorded neuronal activity in the hippocampus while macaque monkeys performed a visual recognition memory task. During the encoding phase of this task, hippocampal neurons displayed gamma-band synchronization. Additionally, enhanced gamma-band synchronization during encoding predicted greater subsequent recognition memory performance. These changes in synchronization reflect enhanced coordination among hippocampal neurons and may facilitate synaptic changes necessary for successful memory encoding.

Abstract: We derive a master stability function (MSF) for synchronization in networks of coupled dynamical systems with small but arbitrary parametric variations. Analogous to the MSF for identical systems, our generalized MSF simultaneously solves the linear-stability problem for near-synchronous states (NSS) for all possible connectivity structures. We also derive a general sufficient condition for stable near-synchronization and show that the synchronization error scales linearly with the magnitude of parameter variations. Our analysis underlines the significant role played by the Laplacian eigenvectors in the study of network synchronization of near-identical systems.

Abstract: A system, method, and computer program product for synchronizing events between a mobile device and a server are described herein. In an embodiment, the method operates by detecting events to be synchronized between a source and a target, wherein the source and target are one of either a mobile device or a server. The method comprises deducing activities that occurred in order to create the detected event, reading data records corresponding to the deduced activities, and creating packets of operations needed to recreate the deduced activities on the target. The method further comprises queuing the packets of operations and data records and receiving event synchronization results at the source after the queued packets of operations have successfully executed on the target, wherein the synchronization results include a synchronization status and a unique record identifier identifying the event. In an embodiment, personal information manager (PIM) events are synchronized.

Abstract: The problem of programming scalable multicore processors has renewed interest in message-passing languages and frameworks. Such languages and frameworks are typically actor-oriented, implementing some variant of the standard Actor semantics. This paper analyzes some of the more significant efforts to build actor-oriented frameworks for the JVM platform. It compares the frameworks in terms of their execution semantics, the communication and synchronization abstractions provided, and the representations used in the implementations. It analyzes the performance of actor-oriented frameworks to determine the costs of supporting different actor properties on JVM. The analysis suggests that with suitable optimizations, standard Actor semantics and some useful communication and synchronization abstractions may be supported with reasonable efficiency on the JVM platform.

Abstract: The aim is to provide high-speed data synchronization. To achieve the aim, in data synchronization using a plurality of key databases with respect to same data pieces, a key for one key database, which has been determined in advance, is used for updating the data piece managed under the other key database. This reduces the number of key decryption operations. A key management software 116, which manages a key database A120 and a key database B121 each having a tree structure, determines whether to perform data synchronization when requested by an upper-level application to perform data encryption, and performs synchronization of encrypted data by using a key of the other database which has been determined in advance. This reduces the number of times the encrypted key is loaded onto a cryptographic processing unit 114, and realizes high-speed cryptographic processing on data.

Abstract: Increasing evidence suggests that neuronal synchronization in the gamma band (30-100 Hz) may play an important role in mediating cognitive processes. Gamma-band synchronization provides for the optimal temporal relationship between two signals to produce the long-term synaptic changes that have been theorized to underlie memory formation. Although neuronal populations in the hippocampus oscillate in the gamma range, the role of these oscillations in memory formation is still unclear. To address this issue, we recorded neuronal activity in the hippocampus while macaque monkeys performed a visual recognition memory task. During the encoding phase of this task, hippocampal neurons displayed gamma-band synchronization. Additionally, enhanced gamma-band synchronization during encoding predicted greater subsequent recognition memory performance. These changes in synchronization reflect enhanced coordination among hippocampal neurons and may facilitate synaptic changes necessary for successful memory encoding.

Abstract: Timing synchronization between base stations of uncoordinated communication networks includes obtaining timing synchronization information from one base station, and adjusting a clock of the other station in response to the synchronization information. The timing synchronization information can be identified from a strongest synchronization signal from nearby uncoordinated base stations. The timing synchronization can accommodate clock offsets and frequency offsets.

Abstract: A mobile communication terminal communicates with a central node to provide automatically synchronization of user content stored on a mobile device with user content stored at a central node, such as at a synchronization server. In this way, automatic two-way synching may be provided, the user may monitor, view, update, change, add to or delete all or any field of user content using a web interface stored for a mobile device at a central node such as at a synchronization server cloud or data storage cloud, using a remote device, including an off-line device. Current location of the mobile terminal may also be tracked at the central node.

Abstract: A data synchronization method for more than three networked devices including at least one client and one server for efficiently synchronizing data among multiple devices supporting a Synchronization Markup Language (SyncML) protocol is provided. The data synchronization method includes determining whether a data item indicated by synchronization information contained in a synchronization request message exists in a change log table of the server, when a server receives the synchronization request message sent by a first client, and updating the change log table by adding the data item indicated by the synchronization information and transmitting a synchronization request message containing a data identifier and the change log of the data item to a second client, if a data item indicated by the synchronization information does not exist, otherwise, ending data synchronization by transmitting a synchronization response message containing status information to the first client.

Abstract: System(s), device(s), and method(s) are provided to supply a device that accesses and utilizes resources in a wireless network under a lease agreement. A system generates service unit bank(s) that enable service utilization and provides a customized operational profile that enables custom configuration of service in the device. The device can receive lessee-specific operational profile(s) and lease agreement term(s), and can regulate a lease agreement. If the lease agreement expires, the device can lock at least a portion of the functionality of the device and provide an environment to renew the lease agreement. If the device is not returned, the system pursues various asset protection mechanism(s), such as assessment of recovery fees and tracking location of the device. Returned device is commissioned for a new lease. Synchronization of lessee-specific operational profiles amongst device and the system, or network external thereto, can be accomplished through a femtocell network or a macrocell network.

Abstract: Research on the secure communication applications of chaotic synchronization is reviewed. A number of secure communication methods and devices using different types of synchronous behavior are examined. For the purpose of comparing existing methods, quantitative characteristics of operating capacity of various schemes are introduced and estimated. An extremely noise-stable secure information transmission method, based on the phenomenon of generalized chaos synchronization, is proposed. All of the methods considered are systematically checked for efficiency for the first time by numerically simulating unidirectionally coupled chaotic Rossler systems selected for transmitting and receiving oscillators. The key advantages and disadvantages of secure information transmission schemes using synchronized chaotic oscillations are discussed. The experimental data gathered in this field are also reviewed.

Abstract: Distributed synthetic aperture radar (DiSAR), including bi- and multistatic SAR, operates with distinct transmitting and receiving antennas that are mounted on separate platforms. Spatial separation has several operational advantages, such as reduced vulnerability in military applications and increased radar cross section (RCS); which may increase the capability, reliability, and flexibility of future aerospace remote sensing missions. However, in this configuration, there is no cancellation of reference oscillator phase noise as in monostatic cases. There are additional technical problems associated with temporal synchronization of the transmit and receive systems. Therefore, highly accurate time and phase synchronization must be provided. Little work on these challenges has been reported. This paper presents a Global Positioning System (GPS)-based technique for achieving successful time and phase synchronization for DiSAR. This technique offers high-frequency stability. More importantly, residual time synchronization errors may be compensated for with a high-precision range alignment method, and residual phase synchronization errors may be compensated for with a subaperture autofocus algorithm.

Abstract: The harmony search (HS) algorithm is a recently developed meta-heuristic algorithm, and has been very successful in a wide variety of optimization problems. HS was conceptualized using an analogy with music improvisation process where music players improvise the pitches of their instruments to obtain better harmony. The HS algorithm does not require initial values and uses a random search instead of a gradient search, so derivative information is unnecessary. Furthermore, the HS algorithm is simple in concept, few in parameters, easy in implementation, imposes fewer mathematical requirements, and does not require initial value settings of the decision variables. In recent years, the investigation of synchronization and control problem for discrete chaotic systems has attracted much attention, and many possible applications. The tuning of a proportional–integral–derivative (PID) controller based on an improved HS (IHS) algorithm for synchronization of two identical discrete chaotic systems subject the different initial conditions is investigated in this paper. Simulation results of the IHS to determine the PID parameters to synchronization of two Henon chaotic systems are compared with other HS approaches including classical HS and global-best HS. Numerical results reveal that the proposed IHS method is a powerful search and controller design optimization tool for synchronization of chaotic systems.

Abstract: A client stores client metadata entries corresponding to a plurality of data objects. During a first phase of a synchronization process, the client sends one or more client metadata entries to a server. Each client metadata entry sent corresponds to a data object for which at least one metadata parameter has changed since a prior execution of the synchronization process. During a second phase of the synchronization process, the client receives from the server one or more server metadata entries, each having at least one parameter that has changed since a prior execution of the synchronization process. The client identifies any received server metadata entry that conflicts with a corresponding client metadata entry, requests a user to select from among a predefined set of conflict resolutions to resolve the conflict, and the performs an action in accordance with the conflict resolution selected by the user.

Abstract: Systems are provided that support millimeter-wave wireless communications between hosts and electronic devices. A host may be formed using a personal computer associated with a user or computing equipment associated with a public establishment. Content can be automatically synchronized between the host and the user's electronic device over a millimeter-wave wireless communications link in a communications band such as a 60 GHz wireless communications band. Synchronization operations may be performed based on user content preferences. Content preference information may be gathered explicitly from a user using on-screen options or may be gathered by monitoring user media playback activities and media rating activities. The content preference information may be transmitted automatically from an electronic device to a host when the electronic device is brought within range of the host. Synchronization operations may be performed automatically when a user is in proximity of a point-of-sale terminal or ticketing equipment.

Abstract: Multiple downlink (DL) and uplink (UL) carriers can enhance wireless communication between nodes and user equipment (UE). Among the carriers, it is beneficial to have some special, by configuration designated carriers to provide synchronization, system information, paging, data and control for multi-carrier enabled UEs. Thereby, overhead system information can be reduced. For instance, synchronization and paging for a certain cell are not provided on all carriers. A carrier can provide backward compatibility for single carrier UEs for access, synchronization, broadcast, and new control region within the data region of the legacy terminals. Coordination between nodes for selecting anchor carriers that mitigate interference and for transmit power control for non-anchor carriers provide further network performance advantages.