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In this paper, we proposed an automatic TOD synchronization and verification method for improving the performance of air-to-ground radio(hereafter SATURN) of legacy aircraft. In order to automatically synchronize TOD with SATURN radio, it is proposed to modify the GPS antenna installed in the existing aircraft according to the minimum operating performance standard. In addition, test methods and results are presented to verify the TOD information generation capability before and after the GPS antenna modifying. It is expected that the automatic TOD synchronization method proposed in this paper can be applied to the SATURN performance improvement design.

A silicon photomultiplier (SiPM) is considered a next generation photo-sensor for low-light applications. In this study, we propose and develop the general concept of a multipurpose submillimeter gamma-ray (MSG) imaging module that is applicable to most gamma-ray imaging devices. The main features of the MSG module are submillimeter intrinsic resolution, geometrically expandable structure, expandable data acquisition system, multi-energy capability and usability in intense magnetic fields. The elements of the gamma-ray detector are pixelated Ce:GAGG ( $31\times 31$ pixels, 0.8 mm pitch), a 1.5-mm acrylic light guide, and one SiPM array ( $8 \times 8$ pixels). The readout electronics are composed of a symmetric charge division resistive network, 16 channel preamplifiers, multiplexing amplifiers, and analog-to-digital converter (ADC) circuits. We use a subminiature field-programmable gate array (FPGA) board as a data acquisition system. To make the system more expandable, we apply a 10 GbE-based tree structure using a FPGA-based data acquisition board and switching hub. To verify multipurpose capabilities, the energy spectra and the flood images are obtained using Co-57, Na-22, and Cs-137 isotopes. We measure temperature characteristics of the detector module. A pinhole image is obtained to confirm high resolution property. The maximal data transfer rate that is measured using dummy gamma-ray event packets is 963.143 Mbps. This detector module can be applied to nuclear medicine imaging devices and radiation monitoring systems.

The study on the development of local food inventory management system is presented. In the case of a current distribution system for small and big stores, the person in charge must be able to check the status right away and be able to fill the display, whenever the amount of displayed products is reduced. However, we have developed the system which alerts suppliers to fill the product, when the weight of the display goes below a certain level from the initial weight of the filled-display using electronic scale for measuring the weight to mobile. With the system, it is able to operate efficiently by real-time sharing of filling-time on mobile. The proposed system can provide customers with fresh products through reduction in labor force and the day of harvest and sale of local food stores, and simplify the distribution channel.

International audience; In 1999, the IAEA has initiated a Coordinated Research Project on ‘‘Updated Codes and Methods toReduce the Calculational Uncertainties of the LMFR Reactivity Effects.’’ Three benchmark modelsrepresenting different modifications of the BN-600 fast reactor have been sequentially established andanalyzed, including a hybrid core with highly enriched uranium oxide and MOX fuel, a full MOX corewith weapons-grade plutonium, and a MOX core with plutonium and minor actinides coming from spentnuclear fuel. The paper describes studies for the latter MOX core model. The benchmark results includecore criticality at the beginning and end of the equilibrium fuel cycle, kinetics parameters, spatialdistributions of power, and reactivity coefficients obtained by employing different computation toolsand nuclear data. Sensitivity studies were performed to better understand in particular the influence ofvariations in different nuclear data libraries on the computed results. Transient simulations were done toinvestigate the consequences of employing a few different sets of power and reactivity coefficientdistributions on the system behavior. The obtained results are analyzed in the paper.

Period jitter plays a critical role in global clock distribution, because it directly impacts the time available for logic operation between sequential elements in the presence of time-varying supply noise. For a given global clock tree topology, the accurate evaluation of period jitter is not only complicated to establish but also exceedingly compute intensive due to its dependency upon many different design parameters. In this paper, we propose a set of analytical expressions which predict period jitter of global clock tree in a fast and accurate manner. A recursive period jitter expression is formulated for global binary clock trees with 32nm rlc interconnects, and it is approximated to a summation based non-recursive expression. Both expressions predict period jitter in the presence of power supply noise with less than 2.93ps error and a speedup of over 100x compared to full-fledged HSPICE simulations The analytical prediction of the worst case period jitter was made possible by the formulation of the non-recursive expression. The worst case period jitter predictions for several different design assumptions closely match the exact worst case period jitter found based on the numerical searches of recursive expression.

Period jitter plays a critical role in global clock distribution design because it directly impacts the time available for logic operation between sequential elements in the presence of time-varying noise. The accurate evaluation of period jitter for a given clock tree topology is not only complicated to establish but also exceedingly time consuming and computer intensive due to its dependency upon many different parameters such as supply noise amplitude, supply noise frequency, clock driver size, physical structures of interconnects, number of clock stages, etc. In this paper, a novel recursive analytical expression is formulated to accurately predict period jitter for general binary global clock distribution trees. Simulation results are presented for a variety of topologies and compared with full-fledged HSPICE models, showing very good accuracy and requiring a fraction of the CPU time. Furthermore, this analytical expression is used to quantify the impact of power supply noise amplitude and frequency on worst-case period jitter and to determine general global clock distribution guidelines for its minimization.