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Full-duplex (FD) communications provide a more efficient and secure architecture for secure communications. It enables both source and destination nodes to generate artificial noise (AN) to interfere with the eavesdropper while still can decode the original signal with a negligible loss. Despite the direct FD transmission, an FD-enabled relay architecture further improves the secrecy rate of secure communications by adding a relay node to the transmission. Nevertheless, it is challenging to implement a stable relay system due to lacking incentives for the potential relay nodes to deliver the messages of others, especially when they have their own messages to transmit. In light of this concern, we propose a double relay model, that is, both source nodes of transmissions pairs relay the messages of each other simultaneously in FD mode so both can benefit from the relay system. This naturally formulates a roommate matching problem, which is a traditional matching problem in game theory. Nevertheless, the proposed problem is different from the existing single-party matching problem as the relay is optional in our system. Thus, we extend the roommate matching problem to support that players can strategically choose to be single. We then propose an improved roommate matching algorithm, which aims to maximize the system secrecy rate and guarantee the incentive of participated pairs. The simulation results confirmed that the proposed algorithm could achieve near-optimal performance.

Nowadays, most of organizations are shifting or shifted from the industrial economy to the knowledge economy. In this new economy, a new set of advanced information technology systems has emerged. Knowledge management systems (KMS) are innovative advanced information systems that have demonstrated a significant value towards individuals and organizational performance. This research aimed for an empirical evaluation on the influence of organizational factors on KMS usage among decision makers in Jordanian banks. In this respect, a survey (self-administered questionnaire) was distributed at the decision makers who are using the KMS's within Jordanian banks, which resulted with 341 valid responses. Structural equation modeling (SEM), in particular AMOS statistical software was employed for further data analysis. Findings revealed that, decision makers' usage of KMS's within Jordanian banks is significantly affected by the extent of top management support, formalization, and centralization.

Terminals of a CPU socket connector dominate signal transmission between the CPU and the motherboard. Contact forces between the terminal of an electronic connector and the corresponding counterparts generally play an important role in signal transmissions. The contact forces of these terminals, however, could decay gradually due to the stress relaxation effect under the high temperature conditions. A finite element analysis is carried out to examine the relaxation phenomenon of the terminal in the present study. The strain-hardening form of the power-law creep model is adopted to account for the relaxation behavior of the terminal material. According to the field life acceleration test specifications established by the Electronic Industry Association (EIA), relationships between the calculated contact force and duration period are then constructed. Moreover, the contact force of the terminal subjected to thermal cycling test is also investigated. Calculations show that the decreased amount of the contact force is rather limited. Associated electrical resistances of the current terminal are further measured to validate the suitability of the contact force as an index of the signal transmission quality.

A new grouped transmitting waveform, with which the conventionally difficult problem of uncoupling time delay and Doppler shift can be solved effectively is proposed. An analysis is given, for locating the geometric center of a target in short range using the proposed waveform. An algorithm for measuring target velocity vector with TR-R/sup 2/ system is analyzed based on the grouped waveform, and formulae for the calculation of velocity vector are derived. System performances are discussed and simulated with the present algorithms.

FMCW is introduced for the first time into a short-range multistatic radar system and an analysis is discussed for locating the geometric center of a thin cylindrical target in short range using the high resolution of the wideband FMCW signal. A method and its expressions for calculating the length of the target are presented. Performance of the system is simulated with the present algorithm; the results given are of practical significance to a certain extent in engineering.

This paper describes a short range target location and speed estimation using the maximum likelihood method based on the range difference information of a T-R multistatic radar system transmitting a new grouped waveform of FMCW signal and single carrier pulse. Formulae are derived independent of transmitter position. Performances are simulated with the proposed algorithm and results are given for various situations.