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221.
J. Ditta K. Kuroda C. Nemoz D. Sillou 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1986,250(3):539-542
A simple delay-line readout method has been tested with a position-sensitive photomultiplier. Position accuracies of the reconstruction by means of a time-to-amplitude convertor are quite comparable to those obtained by a conventional centroid method using a number of analog-to-digital convertors.
In this way, a simple and economic solution can be conceived for the readout of not only position-sensitive photomultipliers, but also arrays of different kinds of position detectors. 相似文献
222.
The statistical analysis of the available data indicated that the straight line equations of protein, fat, fibre, calcium, methionine, and lysine could successively be used for forecasting the added soy percent in a given recipe. On the other hand, the areas of the identified bands in the electropherograms of the investigated samples were considered a reasonable tool for the quantitative determination of whole soybean in soy-based meat substitutes. 相似文献
223.
This study reports results of psychological assessment among military participants in Operation Desert Storm, a more diverse ethnic and gender mix of American troops than has been mobilized for previous military operations. Symptoms of current psychological distress, including negative mood states, somatic complaints, and posttraumatic stress disorder, in addition to personal and trauma characteristics, were measured in 653 Persian Gulf war-zone-exposed and 259 stateside-duty troops to test the hypothesis that ethnic minority status and female gender are associated with greater levels of psychological distress following war-zone duty. Findings point to potentially negative sequelae to war-zone stress in a portion of troops and suggest that ethnic minorities, but not necessarily women, may be more vulnerable to psychological risk. 相似文献
224.
225.
Fazal Tanzeela Iqbal Shahid Shah Mazloom Bahadur Ali Ismail Bushra Abd-Rabboh Hisham S. M. Hameed Rabia Mahmood Qaiser Ibrar Aliya Nasar Muhammad Sufyan Ehsan Yasir Shah Saqib Ahmad Nauman Adnan Qayyum Muhammad Abdul 《Journal of Materials Science: Materials in Electronics》2022,33(1):42-53
Journal of Materials Science: Materials in Electronics - Binary bismuth sulfide (Bi2S3) and ternary aluminum-doped bismuth sulfide (Al@Bi2S3) thin films were prepared by the chemical bath... 相似文献
226.
Ayesha Javed Mir Yasir Umair Alina Mirza Abdul Wakeel Fazli Subhan Wazir Zada Khan 《计算机、材料和连续体(英文)》2021,67(2):1781-1799
With the advent and advancements in the wireless technologies, Wi-Fi fingerprinting-based Indoor Positioning System (IPS) has become one of the most promising solutions for localization in indoor environments. Unlike the outdoor environment, the lack of line-of-sight propagation in an indoor environment keeps the interest of the researchers to develop efficient and precise positioning systems that can later be incorporated in numerous applications involving Internet of Things (IoTs) and green computing. In this paper, we have proposed a technique that combines the capabilities of multiple algorithms to overcome the complexities experienced indoors. Initially, in the database development phase, Motley Kennan propagation model is used with Hough transformation to classify, detect, and assign different attenuation factors related to the types of walls. Furthermore, important parameters for system accuracy, such as, placement and geometry of Access Points (APs) in the coverage area are also considered. New algorithm for deployment of an additional AP to an already existing infrastructure is proposed by using Genetic Algorithm (GA) coupled with Enhanced Dilution of Precision (EDOP). Moreover, classification algorithm based on k-Nearest Neighbors (k-NN) is used to find the position of a stationary or mobile user inside the given coverage area. For k-NN to provide low localization error and reduced space dimensionality, three APs are required to be selected optimally. In this paper, we have suggested an idea to select APs based on Position Vectors (PV) as an input to the localization algorithm. Deducing from our comprehensive investigations, it is revealed that the accuracy of indoor positioning system using the proposed technique unblemished the existing solutions with significant improvements. 相似文献
227.
Muhammad Yasir Faheem Shun''an Zhong Abid Ali Minhas Muhammad Basit Azeem 《北京理工大学学报(英文版)》2019,28(1):103-108
A state of the art ultra-low power small sized transceiver design has been proposed. This device consists of four blocks, including a frequency synthesizer (FS), a crystal oscillator (XO), transmitter and receiver attached with an antenna. It has been seen that wireless information technology and systems have played a vital role in the transformation of society in different aspects of life. Mobile wireless communications including WiMAX/4G have attracted researchers and developers. WiMAX/4G applications need a transceiver that can be used in the worst channel conditions, but with low power consumption and low input voltage at the 5.8 GHz frequency. The proposed transceiver operates on 1.2 V. The operating frequency, noise figure (NF) and receiver gain are 5.8 GHz, 4.0 dB and 90 dB respectively. It is a highly compatible transceiver with all the 4 G technologies. Implementation details and results have revealed that the proposed transceiver is much more efficient than the previously proposed transceivers in literature. 相似文献
228.
针对地震剖面数据中有效层位信息与噪声混合分布,传统方法难以对地震断层进行识别的问题,提出了一种基于连通区域离散度的地震断层识别方法.首先,基于八邻域连通对地震剖面二值图像中的连通区域进行标注并提取每一个连通区域的离散度等数字特征;然后,基于噪声和地震层位各自所属连通区域横向长度和离散度的不同对噪声进行去除;最后,利用地震层位所属连通区域的横向端点信息对地震断层进行识别并标注.通过实验将所提方法与传统方法进行了对比,实验结果验证了所提方法的有效性和实用性. 相似文献
229.
A high‐speed RSD‐based flexible ECC processor for arbitrary curves over general prime field
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Yasir Ali Shah Khalid Javeed Shoaib Azmat Xiaojun Wang 《International Journal of Circuit Theory and Applications》2018,46(10):1858-1878
This workpresents a novel high‐speed redundant‐signed‐digit (RSD)‐based elliptic curve cryptographic (ECC) processor for arbitrary curves over a general prime field. The proposed ECC processor works for any value of the prime number and curve parameters. It is based on a new high speed Montgomery multiplier architecture which uses different parallel computation techniques at both circuit level and architectural level. At the circuit level, RSD and carry save techniques are adopted while pre‐computation logic is incorporated at the architectural level. As a result of these optimization strategies, the proposed Montgomery multiplier offers a significant reduction in computation time over the state‐of‐the‐art. At the system level, to further enhance the overall performance of the proposed ECC processor, Montgomery ladder algorithm with (X,Y)‐only common Z coordinate (co‐Z) arithmetic is adopted. The proposed ECC processor is synthesized and implemented on different Xilinx Virtex (V) FPGA families for field sizes of 256 to 521 bits. On V‐6 platform, it computes a single 256 to 521 bits scalar point multiplication operation in 0.65 to 2.6 ms which is up to 9 times speed‐up over the state‐of‐the‐art. 相似文献
230.
飞行控制设计的最新进展提高了复杂自主飞行器完成各类任务的能力.在各类垂直起降飞行器中,涵道风扇飞行器(DFAVs)是一种非常重要的尾座式飞行器,其运动和驱动部件由称为涵道的环形机身所屏蔽.这一结构使得其能够很好地保护飞行器自身和操作人员的安全,让飞行器能够在狭窄、杂乱和危险的环境中飞行.此外,DFAVs具有固定翼飞机和直升机的特点,能够同时展现它们的优良特性,如长时居高监视能力和大有效载荷能力.本文是关于DFAVs的第1篇综述论文,旨在概述与其相关的几个方面的最新进展.首先,综述了世界范围内开发的此类飞行平台的历史与分类,并总结了它们的优缺点.然后,介绍了用于控制这些飞行器的多种控制方法.最后,给出总结,并讨论了现存的挑战,以及新的研究趋势. 相似文献