A non-magnetic temperature controlling system used in atomic magnetometer with flowing hot air has been designed and realized.To measure the temperature in the oven without any additional magnetic noise,a fiber Bragg grating was used as a non-magnetic temperature measuring sensor with a high relative accuracy.Analysis has showed the temperature fluctuation can be controlled less than O.1 ℃.

关键词：原子密度;非磁性加热;非磁性测量,热空气流动

查看摘要 索取原文[5页]

Based on the phenomenon that Colpitts circuit cannot drive quartz crystal in liquid phase environment,this paper studies the wet sensitive characteristics of Colpitts oscillation circuit.And we designed a device used as humidity sensor.Peltier element was used to cool quartz crystal until dew occurred and quartz crystal worked in the liquidenvironment.Colpitts circuit stopped oscillation when dew occurred.At the same time the temperature of crystal surface was measured and the temperature was approximately regarded as the dew point.Through the theoretical analysis of Colpitts circuit characteristic and the humidity sensing properties of quartz crystal admittance,then combined with experimental data comparison,the wet sensitive characteristics of Colpitts circuit was proved to be feasible and accurate for dew point recognition from the qualitative point.The result is of practical importance for further quantitative analysis and developing sensitive circuit type dew point instrument.

关键词：露点测量;科耳皮兹电路;石英晶体

查看摘要 索取原文[5页]

We are studying adaptive social networks, focusing on spread of infectious disease as our primary example and including terrorist recruitment as an additional example. In an adaptive network, individuals change their social connections in response to their neighbors' characteristics, and these changes in network topology affect subsequent properties of the individuals. The network adaptation can be disease avoidance or connecting to potential recruits. Major goals of the project included extending previous models to incorporate more realistic network structure, adding spread of information that affects human behavior, studying the extinction of diseases, developing control strategies for epidemics on adaptive networks, and developing tools to analyze and monitor adaptive network properties. We have extended models to include network community structure, information spread, and more realistic social adaptation. We developed the first adaptive network model for terrorist recruitment. Our analytic work includes new techniques for predicting extinction rates of epidemics and the trajectory to extinction, methods to apply this to extinction on a network, and new moment closure approximation techniques that lead to more accurate predictions. For monitoring and control, we developed a method to quantify network adaptation and studied vaccine control for epidemics in adaptive networks.

关键词：自适应系统;动力学;自适应网络;人口造型;社会网络;

查看摘要 索取原文[22页]

This report describes a Secure, Autonomous, and Intelligent Controller for Integrating Distributed Emergency Response Satellite Operations. It includes a description of current improvements to existing Virtual Mission Operations Center technology being used by US Department of Defense and originally developed under NASA funding. The report also highlights a technology demonstration performed in partnership with the United States Geological Service for Earth Resources Observation and Science using DigitalGlobe(Registered TradeMark) satellites to obtain space-based sensor data.

关键词：控制器；集成；分布式应急卫星业务；安全；自治；智能

查看摘要 索取原文[10页]

ragonfly is a password authenticated key exchange protocol that has been submitted to the Internet Engineering Task Force as a candidate standard for general internet use. We analyzed the security of this protocol and devised an attack that is capable of extracting both the session key and password from an honest party. This attack was then implemented and experiments were performed to determine the time-scale required to successfully complete the attack.

关键词：数据处理;攻击;认证;通信协议

查看摘要 索取原文[13页]

The classical mean shift (MS) algorithm is the best color-based method for object tracking.However,in the real environment it presents some limitations,especially under the presence of noise,objects with partial and full occlusions in complex environments.In order to deal with these problems,this paper proposes a reliable object tracking algorithm using corrected background-weighted histogram (CBWH) and the Kalman filter (KF) based on the MS method.The experimental results show that the proposed method is superior to the traditional MS tracking in the following aspects:1) it provides consistent object tracking throughout the video; 2) it is not influenced by the objects with partial and full occlusions; 3) it is less prone to the background clutter.

关键词：目标跟踪;均值漂移;背景资料;卡尔曼滤波器;通信

查看摘要 索取原文[6页]

Communication, i.e., moving data, between levels of a memory hierarchy or between parallel processors on a network, can greatly dominate the cost of computation, so algorithms that minimize communication can run much faster (and use less energy) than algorithms that do not. Motivated by this, attainable communication lower bounds were established for a variety of algorithms including matrix computations. The lower bound approach used initially for Theta(N3) matrix multiplication, and later for many other linear algebra algorithms, depended on a geometric result by Loomis and Whitney: this result bounded the volume of a 3D set (representing multiply-adds done in the inner loop of the algorithm) using the product of the areas of certain 2D projections of this set (representing the matrix entries available locally, i.e., without communication). Using a recent generalization of Loomis' and Whitney's result, we generalize this lower bound approach to a much larger class of algorithms, that may have arbitrary numbers of loops and arrays with arbitrary dimensions as long as the index expressions are a ne combinations of loop variables. In other words, the algorithm can do arbitrary operations on any number of variables like A(i(sub 1), i(sub 2), i(sub 2) - 2i(sub 1), 3 - 4i(sub 3) + 7i(sub 4), ...). Moreover, the result applies to recursive programs, irregular iteration spaces, sparse matrices, and other data structures as long as the computation can be logically mapped to loops and indexed data structure accesses. We also discuss when optimal algorithms exist that attain the lower bounds; this leads to new asymptotically faster algorithms for several problems.

关键词：微分方程；线性代数；通信；数据结构；数据传输

查看摘要 索取原文[48页]

Devices that provide hearing protection, situational awareness and radio communications are often referred to as Communications and Hearing Protection Systems (C&HPS). Soldiers use these systems to maintain auditory awareness within their environment, communicate with their team members and protect their hearing. Each of the three features of select C&HPS (hearing protection, speech communication and situational awareness) were independently evaluated by the U.S. Army Research Laboratory (ARL). This report is the third in a series of three and focuses on the auditory localization performance obtained from two commercially available C&HPS: Nacre QuietPro and Silynx QuietOps. These two systems were selected from three C&HPS evaluated for attenuation characteristics in the first report and speech intelligibility in the second report; the third system provided insufficient attenuation to be included. Results of the auditory localization testing indicated that both C&HPS negatively affected auditory localization accuracy performed in background noise, but the observed decrement was not significantly different between the two systems. Evidence from objective measures of the systems such as directivity, calculation of interaural level differences (ILDs), and the measurement of input/output functions indicate that changes in binaural intensity difference cues were the primary factor driving the reduction in performance.

关键词：通信和广播系统;背景噪音;语音通信;输入输出处理

查看摘要 索取原文[40页]

The objective of this project is the extension of the Parallel Tools Platform (PTP) for applying it to peta-scale systems. PTP is an integrated development environment for parallel applications. It comprises code analysis, performance tuning, parallel debugging and system monitoring. The contribution of the ulich Supercomputing Centre (JSC) aims to provide a scalable solution for system monitoring of supercomputers. This includes the development of a new communication protocol for exchanging status data between the target remote system and the client running PTP. The communication has to work for high latency. PTP needs to be implemented robustly and should hide the complexity of the supercomputer's architecture in order to provide a transparent access to various remote systemerent systems, because PTP functions as abstraction layer between parallel application developer and compute resources. The common requirement for all PTP components is that they have to interact with the remote supercomputer. E.g. applications are built remotely and performance tools are attached to job submissions and their output data resides on the remote system. Status data has to be collected by evaluating outputs of the remote job scheduler and the parallel debugger needs to control an application executed on the supercomputer. The challenge is to provide this functionality for peta-scale systems in real-time.

关键词：电脑；并行处理器；计算机体系结构；计算机通讯

查看摘要 索取原文[9页]

Matrix multiplication is one of the most fundamental algorithmic problems in numerical linear algebra, distributed computing, scientific computing, and high-performance computing. Parallelization of matrix multiplication has been extensively studied (e.g., 21, 12, 24, 2, 51, 39, 36, 23, 45, 61). It has been addressed using many theoretical approaches, algorithmic tools, and software engineering methods in order to optimize performance and obtain faster and more efficient parallel algorithms and implementations. To design efficient parallel algorithms, it is necessary not only to load balance the computation, but also to minimize the time spent communicating between processors. The interprocessor communication costs are in many cases significantly higher than the computational costs. Moreover, hardware trends predict that more problems will become communication-bound in the future 38, 35. Even matrix multiplication, which is widely considered to be computation-bound, becomes communication-bound when a given problem is run on sufficiently many processors.

关键词：算法;分布式数据处理;软件工程;通信

查看摘要 索取原文[93页]