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31.
This article presents the results of a time-limited psychological relief effort using eye movement desensitization and reprocessing (EMDR) following the attacks on the World Trade Center on September 11, 2001. Clients made highly significant positive gains on a range of outcome variables, including validated psychometrics and self-report scales. Analyses of the data suggest 2 broad conclusions: EMDR is a useful treatment intervention both in the immediate aftermath of disaster as well as later; the longer treatment is delayed, the greater the level of disturbance experienced by clients. Also discussed are problems in conducting research during mass disaster response situations. A demonstration of an analog to a wait-list control group is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
加密设备接口标准研究及实现分析   总被引:2,自引:0,他引:2  
加密设备的接口规范是网络安全能统一实施的关键。Cryptoki是基于PKCS#11加密设备接口标准的编程接口,可用于各种可移植的密码设备。本文在阐述Cryptoki通用模型特点的基础上,具体分析了作为Unix类平台工业标准的OpenCryptoki的实现过程,为基于相关标准的编程接口的开发提供了参考。  相似文献   
33.
Bernhard Klinger 《Computing》1997,59(3):223-236
We investigate quasi-Monte Carlo integration for functions on thes-dimensional unit cube having point singularities. Error bounds are proved and the theoretical results are verified by computations using Halton, Sobol’ and Niederreiter sequences. Supported by the Austrian Science Foundation (Project 10223-PHY).  相似文献   
34.
本文简要地介绍了我国粉末涂料的发展概况,并概述了热固性和热塑性粉末涂料的应用领域.文章重点介绍了尼龙-11粉末涂料的优点及其制造法,阐述了其在管道防腐、船体防护和建筑行业等领域的应用  相似文献   
35.
介绍PDP11—24计算机在兰州炼油化工总厂第一套催化裂化装置的应用情况,其内容包括数据采集、软件开发、数据通讯等。  相似文献   
36.
A Peer-to-Peer Approach to Web Service Discovery   总被引:9,自引:0,他引:9  
Web Services are emerging as a dominant paradigm for constructing and composing distributed business applications and enabling enterprise-wide interoperability. A critical factor to the overall utility of Web Services is a scalable, flexible and robust discovery mechanism. This paper presents a Peer-to-Peer (P2P) indexing system and associated P2P storage that supports large-scale, decentralized, real-time search capabilities. The presented system supports complex queries containing partial keywords and wildcards. Furthermore, it guarantees that all existing data elements matching a query will be found with bounded costs in terms of number of messages and number of nodes involved. The key innovation is a dimension reducing indexing scheme that effectively maps the multidimensional information space to physical peers. The design and an experimental evaluation of the system are presented.  相似文献   
37.
National traumatic events can produce extremely vivid memories. Using a questionnaire administered during telephone interviews, the authors investigated emotional responses to, and memory for. the September 11, 2001, terrorist attacks in patients with Alzheimer's disease (AD), patients with mild cognitive impairment (MCI), and healthy older adults in the initial weeks following the event and again 3-4 months later. There were several notable findings. First, patients with AD showed less memory than patients with MCI and older adults. Second, patients with AD, but not patients with MCI or older adults, appeared to retain more memory for personal versus factual information. Third, patients with AD and older adults did not differ in the intensity of their reported emotional responses to the attacks, whereas patients with MCI reported relatively less intense emotional responses. Last, distortions of memory for personal information were frequent for all participants but were more common in patients with AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
38.
A study of the effects of small-angle specimen tilt on high-resolution annular dark field images was carried out for scanning transmission electron microscopes with uncorrected and aberration-corrected probes using multislice simulations. The results indicate that even in the cases of specimen tilts of the order of 1 degree a factor of 2 reduction in the contrast of the high-resolution image should be expected. The effect holds for different orientations of the crystal. Calculations also indicate that as the tilted specimen gets thicker the contrast reduction increases. Images simulated with a low-angle annular dark field detector show that tilt effects are more pronounced in this case and suggest that these low-angle detectors can be used to correct specimen tilt during scanning transmission electron microscopes operation.  相似文献   
39.
In the interaction between ultrafast laser pulses and a field emitter both optical and thermal processes are involved. In this paper, these physical process, and their timescales, are experimentally explored. Simple models are proposed to explain the observed experimental behaviour, and the influence of various parameters are investigated. In the case of optical processes, it is shown that the optical field is greatly enhanced at the tip apex, and that field evaporation could be induced by an optical non-linear effect called optical rectification. In the case of thermal processes, it is shown that the temperature rise because of light absorption can be determined and that the cooling process of the tip surface can be studied by pump probe measurements.  相似文献   
40.
无线局域网中一种自适应RTS门限调整算法   总被引:6,自引:0,他引:6  
刘军  郭伟  黄飞  肖百龙 《计算机学报》2007,30(4):547-554
媒体访问控制是无线局域网的重要部分,决定了具有受限通信带宽的无线信道的共享效率.IEEE 802.11系列标准基于现有以太网技术,具有良好的操作性和兼容性,已发展成为WLAN的主要标准.IEEE 802.11 DCF中有两种接入方式:基本方式和RTS/CTS方式.RTS/CTS方式是IEEE 802.11无线网络的可选握手过程,用于减小碰撞的可能性.决定使用RTS/CTS握手方式的RTS门限值是研究的重要参数,不同的取值对数据传送会产生不同的性能特点.文章通过分析IEEE 802.11 DCF分组发送成功和碰撞的持续时间,获得了RTS和基本方式下分组传输时间开销与分组长度的关系.给出了以最小化分组传输时间代价为优化目标的最优RTS门限的计算公式.通过对当前信道分组发送的冲突概率的预测实现了最优RTS门限的计算;给出了一个具体的RTS门限自适应调整算法,使终端能自动调整其RTS门限以达到或接近最优值.仿真表明RTS门限自适应调整算法明显减小了分组传送时收发器发送单位比特数据的时间开销.  相似文献   
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