This investigation examines the durability of the Quantum Dot Mode- Locked Laser (QDMLL) for use in extreme environments where ionizing radiation is a threat. These QDMLLs are fabricated using dots-in-a-well (DWELL) epitaxial structures, which utilize the unique properties of 2D and 3D quantum structures to achieve low-threshold current density in an exceptionally durable gain medium. The research at the University of New Mexico summarized in this report details the radiation hardness of the mode-locking characteristics of the lasers themselves. We show that the devices tested continue to perform well even after being dosed with sufficient ionizing radiation to simulate a long mission at geostationary orbit altitudes.

关键词：量子理论；抗辐射加固；卫星通信；灵敏度

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The objective of this research is to explore the technical soundness of a very large, cross-shaped, parabolic, sparse aperture antenna extending 75 m from the bus. Specifically, describing the environment of the satellite, the effect of fabrication error on the structure and the remaining error budget for the system. The methodology involves creation of an ideal truss structure, to which all others are compared. A uniform distribution of proportional errors up to 1e-5 is introduced into the truss members. lengths and the models are subjected to a static Finite Element Analysis. A solution for the surface normal error is addressed using Lagrange multipliers. The goal is to hold the surface normal error for the entire satellite below a root mean square of 15 mm. The analysis yields a surface error of less than 1.53 mm, well within requirements. Despite the enormous size of the antenna reflector, and tight diameter/surface error ratio of 10,000 required for L-band communication, the system seems feasible. The values achieved for truss induced surface errors are in line with established techniques for analyzing full aperture, and strip, mesh antennas. With the mesh reflector and truss largely defined, nearly half of the 15 mm error budget remains.

关键词：空军研究；孔径天线；天线阵列；通信卫星

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No abstract available.

关键词：大气；通信；造型；国家安全；导航

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关键词：汽车；轻型汽车技术；二氧化碳排放

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In this chapter, we proposed a new peer-to-peer approach for the tree-based B&B algorithm. This approach is based on fully distributed algorithms dealing with work sharing and termination detection in an asynchronous FIFO message passing communication model. Using a small-degree, small-diameter network overlay, we argued that this approach allows us to improve the scalability of the state-of-the-art master-slave approach by controlling the overhead in terms of message exchanged and increasing the overall parallel efficiency. We also show by extensive experiments that our P2P approach effectively scales well and induces significant improvements to the the master-slave approach. Although our algorithms were discussed in the specific context of permutation-based problems and parallel B&B, it is not difficult to see that it can be extended to other contexts. Roughly speaking, for that purpose one must define the following features depending on the application context: (ⅰ) an encoding of work units (intervals), (ⅱ) the processing of work units (sequential B&B), and (ⅲ) the global information that needs to be shared (best B&B solution).

关键词：对等方式；B＆B算法；分布式算法；通信

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Embedded memory plays a big role in digital systems applications due to the increase of the data size required by many of these applications, such as video games and communication protocols. Also, the ever-increasing gap between processor speed, main memory, and bus speed (memory wall) creates a need for more on-chip memory to keep the processor busy and increase throughput. In addition to the increase of processor frequency, the integration of many cores or functional units on the same chip, which is referred to as system on chip (SOC), requires larger memory size. Embedded memory compromises more than 50 % of the chip area and greater than 80 % of transistor counts. Increased process variation due to technology scaling and the desire for high density memory results in a big challenge to meet the stringent requirements on performance, power, and yield. Embedded memory does not only play a positive role in system performance, but it also has an impact on yield, timing, and power. Memory organization and early decision made by system level and architecture group have big influence on the role and the impact the memory has on the overall system. Tradeoffs from memory cell type, array organization, memory hierarchy, Design for Test, and overall memory subsystem have to be considered early on.

关键词：嵌入式存储器；数字系统；处理器；通信

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Communication plays a central role in parallel computing algorithms. For collective communication, significant gains in performance can be achieved by implementing topology- and performance-aware collectives. In this chapter, we offer a comprehensive overview of the existing research in this area. We observe both message passing interface (MPI) collectives as well as alternatives from the distributed computing domain. The existing challenges in analytical and experimental solutions for heterogeneous platforms are presented and discussed.

关键词：算法；通信；拓扑；消息传递接口

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This chapter is an overview of the development of ICT in Israeli Education, from the first pioneers in the second half of sixties to first half of the nineties, when I (first named author of this chapter) gradually passed on my responsibilities, near to my retirement. It covers policy matters, as revealed in the first published policy papers, some of the main actions and projects executed according to these policies - integrating ICT in the learning process; teaching ICT subjects; integrating use of ICT means in humanities, sciences and professional education; ICT in educational management; principals', teachers' and staff training, support and updating and some related organizational details. It ends with a glimpse to recent problems and policy decisions.

关键词：计算机教育；以色列；学校；通信

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The legged robots have emerged by the necessity of vehicles capable of travel and access safely on natural or unstructured terrains, in which vehicles with traditional travel systems (like the wheels) are unable to access, or if they achieve, they move on them with very low efficiency. However, despite the advantages of mobile robots with legs, there are limitations that hinder its use like the control of movement of their legs, the algorithm of locomotion, trajectory tracking and the obstacle avoidance. In our days, a very useful alternative applied to control systems is fuzzy logic; this one is capable of modeling mathematical complex systems. Therefore, fuzzy logic has been becoming popular in control systems for complex and nonlinear plants. The aim of this work is to make algorithms to control the hexapod robot body. The development of these algorithms uses fuzzy logic techniques for controlling the servomotors of the robot. Matlab algorithms are performed to establish a wireless communication using the ZigBee communication protocol, and we use the genetic algorithm toolbox from Matlab to make the control of the hexapod robot body in the "x-y" plane, this is a multi-objective optimization problem due to the stabilization of the robot body in "x" and the stabilization of the robot body in "y".

关键词：腿式机器人；行程系统；模糊逻辑；通信

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We investigate a communication scenario in which two in-ertial observers attempt to securely communicate quantum information via a noisy channel in the presence of a uniformly accelerating eavesdropper. Due to her acceleration, the eavesdropper is subject to Unruh noise which can potentially be exploited to design a secure communication protocol. This problem had previously been studied by Panangaden and co-authors for the special case in which the channel between the inertial observers is noiseless. In this article, we consider noise in the form of a lossy bosonic channel. Our calculations demonstrate that for a fixed acceleration, there is a secure communication protocol provided the noise is below a threshold value.

关键词：相对论量子信息；私人量子容量；通信

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