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非织造成网机用接收网带的性能与选用
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作者 司徒元舜 李孙辉 +1 位作者 胡晓航 刘春玲 《纺织导报》 CAS 北大核心 2014年第6期130-130,132-134,136,137,共6页
网带是纤维的载体,是接收装置的核心,透气量、剥离性能、附着性能是其主要性能。对于生产轻薄型产品的生产线,网带要具备良好的抗静电性能。本文详细介绍了成网机接收网带的性能指标,并就选择原则进行了分析。
关键词 熔体纺丝成 接收网 透气量 剥离性能 附着性能
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新型接入网设备──MF160型数字用户载波集中器
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作者 黄凯雄 苟兴诗 《四川通信技术》 1996年第2期41-43,共3页
新型接入网设备──MF160型数字用户载波集中器四川省邮电科研规划院黄凯雄,苟兴诗1.概述在通信网中从端局到用户之间的网络称为用户网或接入网,其中的线路部分为用户环路。在整个通信网的投资中,用户网的投资比例都较大。如... 新型接入网设备──MF160型数字用户载波集中器四川省邮电科研规划院黄凯雄,苟兴诗1.概述在通信网中从端局到用户之间的网络称为用户网或接入网,其中的线路部分为用户环路。在整个通信网的投资中,用户网的投资比例都较大。如何使用户网达到价廉,高效及高可靠性... 展开更多
关键词 电话交换机 接收网设备 载波集中器 集中器
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通讯卫星地面接收站概述
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作者 兜鍪 《电化教育研究》 1986年第2期75-80,共6页
利用通讯卫星进行教育电视广播,是人类推广应用空间技术的重大发展。现在中央正建立'卫星教育电视中心',已租用第五代国际通信卫星开辟教育频道,定于今年7月试播,10月正式开播。相信我国的电化教育事业,必将随着卫星教育电视接... 利用通讯卫星进行教育电视广播,是人类推广应用空间技术的重大发展。现在中央正建立'卫星教育电视中心',已租用第五代国际通信卫星开辟教育频道,定于今年7月试播,10月正式开播。相信我国的电化教育事业,必将随着卫星教育电视接收网的建设得以迅速的普及。 展开更多
关键词 卫星地面接收 卫星教育 国际通信卫星 卫星电视接收 教育频道 电视中心 接收网 下变频器 卫星电视信号 转发器
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A Low Noise,High Linearity CMOS Receiver for 802.11b WLAN Applications
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作者 黄煜梅 王静光 +1 位作者 王金菊 洪志良 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1708-1714,共7页
A 2.4GHz monolithic CMOS receiver with direct-conversion architecture is presented. This quadrature receiver is designed for 802.11b wireless LAN applications at the maximum data rate of 11Mbps as a low-cost solution.... A 2.4GHz monolithic CMOS receiver with direct-conversion architecture is presented. This quadrature receiver is designed for 802.11b wireless LAN applications at the maximum data rate of 11Mbps as a low-cost solution. Five key blocks,i, e., a low noise amplifier (LNA), a down-conversion mixer, a variable gain amplifier, a low pass filter, and a DC- offset cancellation circuit,are designed based on system design and low noise high linearity considerations. The necessary auxiliary circuits are also included. Fabricated in SMIC 0.18μm 1p6m RF CMOS process, the receiver's performance is measured as:4. 1 dB noise figure, - 7.5dBm input third order intercept point (IIP3) for LNA & mixer at high gain setting, - 14dBm IIP3 for the whole receiver,53dBc @30MHz offset of adjacent channel power rejection,and less than 5mV out- put DC-offset. The receiver consumes 44mA under a 1.8V power supply with I,Q two paths. 展开更多
关键词 802.11b wireless LAN RECEIVER DC-offset cancellation MIXER
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把自己的全部心血献给档案事业——记杨仁录同志
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作者 严建民 《浙江档案》 北大核心 1989年第8期20-20,共1页
她叫杨仁录,原是一位教师。1985年3月,杨仁录调到景宁县人民法院担任档案员。当时,客观条件极其艰苦,所有档案杂乱无章地堆放在云和县,直到1986年5月,杨仁录同志和县法院的领导及干部,克服了重重困难,挤出一间办公室作档案室,才从云和... 她叫杨仁录,原是一位教师。1985年3月,杨仁录调到景宁县人民法院担任档案员。当时,客观条件极其艰苦,所有档案杂乱无章地堆放在云和县,直到1986年5月,杨仁录同志和县法院的领导及干部,克服了重重困难,挤出一间办公室作档案室,才从云和县接回全部档案。尔后,杨仁录同志用了一年多的时间,重新整理了13015卷诉讼、文书和会计档案。 展开更多
关键词 档案事业 档案员 会计档案 景宁县 就这样 告诉我 使人 有毒的 贵一 接收网
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用GPS卫星测量地球上不足一英寸的距离
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作者 Geoffrey Blewitt 张永仙 《地球物理学进展》 CSCD 1992年第2期90-91,共2页
利用追踪全球定位系统(GPS)卫星的世界范围接收网的实验数据“测量地球”这种最近发展起来的技术在1991年显露出身手不凡,最近的结果表明,地球表面相距10000km的点可以测量到2cm的精度,地球旋转轴每天的地表位置也可以估算到2cm的误差内... 利用追踪全球定位系统(GPS)卫星的世界范围接收网的实验数据“测量地球”这种最近发展起来的技术在1991年显露出身手不凡,最近的结果表明,地球表面相距10000km的点可以测量到2cm的精度,地球旋转轴每天的地表位置也可以估算到2cm的误差内.用一种可信的、经济的方法获得这个水平的精度是建立我们对地球的自转及变形知识的重要步骤. 展开更多
关键词 卫星测量 GPS 接收网 实验数据 卫星轨道 卫星激光测距 大气水 随机变化 德克萨斯大学 日平均值
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卫星广播系统的组成及特点的分析与阐述
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作者 肖大宇 《黑龙江科技信息》 2016年第5期2-2,共1页
在我国,曾经以微波方式来传播广播信号。而在科技有了明显进步之后,传播方式已经有了较大的改变,广播信号在现阶段多以卫星方式与光纤方式传播。其中,卫星广播系统具有非常显著的优越性,覆盖范围极广、传播效果非常优秀。究其组成部分,... 在我国,曾经以微波方式来传播广播信号。而在科技有了明显进步之后,传播方式已经有了较大的改变,广播信号在现阶段多以卫星方式与光纤方式传播。其中,卫星广播系统具有非常显著的优越性,覆盖范围极广、传播效果非常优秀。究其组成部分,主要为上行发射站、星体与地面接收网。在本文中,笔者试对其组成部分与特点进行详细的阐述。 展开更多
关键词 上行发射站 星体 地面接收网 卫星广播系统 组成 特点
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Agilent天线测试系统测量误差分析 被引量:1
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作者 侯兴平 朱晓玫 侯玥 《电子世界》 2013年第7期165-166,共2页
本文主要介绍Agilent天线测试系统的组成及工作原理和该天线测试系统测量误差分析以及在实际测试当中的应用。
关键词 地面外来反射误差 标准增益误差 失配误差 接收机线性误差 接收机隔离误差 信噪比测量误差 总的合成测量误差 改善失配误差
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Secure and efficient multi-message and multi-receiver ID-based signcryption for rekeying in ad hoc networks 被引量:5
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作者 邱婧 BAI Jun +1 位作者 SONG Xin-chuan HOU Su-mei 《Journal of Chongqing University》 CAS 2013年第2期91-96,共6页
In this paper, the security technology of ad hoc networks is studied.To improve the previous multi-receiver signcryption schemes, an ID-based multi-message and multi-receiver signcryption scheme for rekeying in ad hoc... In this paper, the security technology of ad hoc networks is studied.To improve the previous multi-receiver signcryption schemes, an ID-based multi-message and multi-receiver signcryption scheme for rekeying in ad hoc networks is proposed.In this scheme, a sender can simultaneously signcrypt n messeges for n receivers, and a receiver can unsigncrypt the ciphertext to get his message with his own private key.An analysis of this scheme indicates that it achieves authenticity and confidentiality in the random oracle model while being of lower computation and communication overhead.Finally, for the application of our scheme in ad hoc, a threshold key updating protocol for ad hoc networks is given. 展开更多
关键词 SIGNCRYPTION multi-receiver multi-message bilinear pairings provable security ad hoc networks introduction
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TCP-Rab: a receiver advertisement based TCP protocol 被引量:4
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作者 汤旭红 刘正蓝 朱淼良 《Journal of Zhejiang University Science》 EI CSCD 2004年第11期1352-1360,共9页
With the evolution of network technologies, the deficiencies of TCP protocol are becoming more and more distinct. The new TCP implementation, called Receiver Advertisement Based TCP (TCP-Rab) proposed here to eliminat... With the evolution of network technologies, the deficiencies of TCP protocol are becoming more and more distinct. The new TCP implementation, called Receiver Advertisement Based TCP (TCP-Rab) proposed here to eliminate these deficiencies, adopts two basic mechanisms: (1) Bandwidth Estimation and (2) Immediate Recovery. Bandwidth estimation is carried out at the receiver, and the result is sent back to the sender via the acknowledgments. Immediate Recovery guarantees high performance even in lossy link. Rab can distinguish the reason for packet loss, and thus adopt appropriate recovery strategy. For loss by network congestion, it will back off its congestion window, and for loss by link errors, it will recover the congestion window immediately. Simulations indicated that Rab has superiority over other TCP implementations. 展开更多
关键词 Bandwidth Estimation Immediate Recovery TCP protocol
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Controlled Remote State Preparation 被引量:2
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作者 WANG Zhang-Yin LIU Yi-Min +1 位作者 ZUO Xue-Qin ZHANG Zhan-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期235-240,共6页
We present a scheme for remotely preparing a state via the controls of many agents in a network.In thescheme,the agents' controls are achieved by utilizing quantum key distribution.Generally,the original state can... We present a scheme for remotely preparing a state via the controls of many agents in a network.In thescheme,the agents' controls are achieved by utilizing quantum key distribution.Generally,the original state can berestored by the receiver with probability 1/2 if all the agents collaborate.However,for certain type of original states therestoration probability is unit. 展开更多
关键词 controlled remote state preparation quantum key distribution single-qubit von Neumann orthogonal measurement controlled-NOT gate
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A sink moving scheme based on local residual energy of nodes in wireless sensor networks 被引量:4
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作者 谭长庚 许可 +1 位作者 王建新 陈松乔 《Journal of Central South University》 SCIE EI CAS 2009年第2期265-268,共4页
In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving ... In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving scheme for the sink based on local residual energy was proposed.In the scheme,the sink periodically moves to a new location with the highest stay-value defined by the average residual energy and the number of neighbors.The scheme can balance energy consumption and prevent nodes around sink from draining their energy very quickly in the networks.The simulation results show that the scheme can prolong the network lifetime by 26%-65%compared with the earlier schemes where the sink is static or moves randomly. 展开更多
关键词 wireless sensor network network lifetime moving scheme residual energy
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Research on the Pragmatics of Politeness Principle of Bulletin Board System based on the Differences of Gender and Habits
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作者 Guojun Li 《International Journal of Technology Management》 2015年第9期56-58,共3页
In this paper, we conduct research on the pragmatics of politeness principle of bulletin board system based on the differences of gender and habits. The openness of the Internet makes all kinds of information received... In this paper, we conduct research on the pragmatics of politeness principle of bulletin board system based on the differences of gender and habits. The openness of the Internet makes all kinds of information received into the vision of an equal chance and web sites in order to improve the hit rate which causes the traffic of commercial purposes such as tabloidization tend to be more negative news spread. To strengthen the research of network language management strategy, it has very important theoretical significance and practical meaning analyzed. Our proposed methodology will help researchers to understand the approaches to use the pragrnatics of politeness. 展开更多
关键词 Bulletin Board System (BBS) Politeness Principle Gender and Habits.
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Optimizing network receive performance in Xen
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作者 张翔 Meng Dan +1 位作者 Huo Zhigang Ma Jie 《High Technology Letters》 EI CAS 2012年第4期350-356,共7页
This paper presents two optimizations to improve the network receive performance in Xen, espe- cially for receiving small packets, by reducing per-packet overhead of network virtualization. First, the universal receiv... This paper presents two optimizations to improve the network receive performance in Xen, espe- cially for receiving small packets, by reducing per-packet overhead of network virtualization. First, the universal receive aggregation assembles incoming packets to decrease the cost of software bridge and bridge netfilter, no matter which protocol these packets use or whether they belong to the same TCP link. Second, the grant page sharing makes as many packets as possible share a single grant page to decrease the cost of expensive grant operations effectively. Experiment demonstrates that compared with default network virtualization in Xen, these two optimizations can reduce CPU cycles per packet by 31.20%, and improve UDP and TCP throughput by 37.73% and 25.62% on average. 展开更多
关键词 VIRTUALIZATION network performance optimization AGGREGATION grant page
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A Super Low Power CMOS Receiver for High Resolution Epi-retinal Prosthesis
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作者 J.W. Yang N. Tran S. Bai D.C. Ng M. Halpern E. Skafidas 《Journal of Energy and Power Engineering》 2010年第8期32-39,共8页
The authors report a super low power Medical Implant Communication Service (MICS) band receiver for a high resolution epi-retinal prosthesis (BionicEye). The frequency shift keying (FSK) receiver consumes less t... The authors report a super low power Medical Implant Communication Service (MICS) band receiver for a high resolution epi-retinal prosthesis (BionicEye). The frequency shift keying (FSK) receiver consumes less than 1.5 mW power with 1 V supply. It is able to achieve a maximum data rate of 400 kb/s. This paper presents the research work carried out on designing a fully-integrated sub-threshold receiver fabricated on a 65 nm complimentary metal oxide semiconductor (CMOS) chip. In order to achieve super low power consumption, more than 90% of the transistors in all analog building blocks are operated in sub-threshold region. System level issues, such as required receiver architecture and specifications are also addressed. 展开更多
关键词 Super low power fully-integrated SUB-THRESHOLD MICS band. BionicEye.
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New Interference Estimation for Power Control in Wireless Networks
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作者 Pyung-soo KIM Jeong-hun CHOI +2 位作者 Eung-hyuk LEE Doo-hee JUNG Eung-tae KIM 《Journal of Measurement Science and Instrumentation》 CAS 2010年第2期152-156,共5页
This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fl... This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fluctuation of interference power and the measurement noise due to receiver noise. The well-known Finite Impulse Response (FIR) structure filter is adopted for both the interference and the noise covarianee estimation. The proposed mechanism provides both the filtered interference power and the filtered number of active co-channel interferers, which shows good inherent properties. And the filtered interference power is not affected by the constant number of active co-channel interferes. It is also shown that the filtered number of active co-channel interference is separated from the filtered interference power. From discussions about the choice of design parameters such as window length and eovariance ratio, they can make the estimation performance of the proposed FIR filtering based mechanism as good as possible. Via extensive computer simulations, the performance of the proposed mechanism is shown to be superior to the existing Kalman filtering based mechanism. 展开更多
关键词 power control interference estimation FIR filtering Kalman filtering
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Maximum Data Collection Rate in Rechargeable Wireless Sensor Networks with Multiple Sinks 被引量:2
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作者 GAO Demin LIN Haifeng +1 位作者 LIU Yunfei WU Guoxin 《China Communications》 SCIE CSCD 2016年第2期95-108,共14页
In rechargeable wireless sensor networks, a sensor cannot be always benefi cial to conserve energy when a network can harvest excessive energy from the environment due to its energy replenished continually and limited... In rechargeable wireless sensor networks, a sensor cannot be always benefi cial to conserve energy when a network can harvest excessive energy from the environment due to its energy replenished continually and limited energy storage capacity. Therefore, surplus energy of a node can be utilized for strengthening packet delivery efficiency and improving data collection rate. In this work, we propose an algorithm to compute an upper data generation rate that maximizes it as an optimization problem for a network with multiple sinks, which is formulated as a linear programming problem. Subsequently, a dual problem by introducing Lagrange multipliers is constructed, and subgradient algorithms are used to solve it in a distributed manner. The resulting algorithms are guaranteed to converge to an optimal data generation rate, which are illustrated by an example in which an optimum data generation rate is computed for a network of randomly distributed nodes. Through extensive simulation and experiments, we demonstrate our algorithm is efficient to maximize data collection rate in rechargeable wireless sensor networks. 展开更多
关键词 wireless sensor networks maximumdata collection rate linear programming rechargeable-WSNs
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Environmental Information Statement for Home Appliances at Online Stores in Japan
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作者 Kayoko Yamamoto Syuichi Kubota 《Journal of Environmental Science and Engineering(A)》 2013年第6期388-403,共16页
This study aims to identify the current situation and problems of environmental information statement for major four home appliances (refrigerators, washing machines, air conditioners and television receivers) sold ... This study aims to identify the current situation and problems of environmental information statement for major four home appliances (refrigerators, washing machines, air conditioners and television receivers) sold at online stores in Japan, and then to suggest how to improve the situation, through a questionnaire survey conducted among businesses that operate online stores and online malls with multiple online stores. The findings of this study are summarized into the following two points: (l) It is found out that environmental information statement for the home appliances at online stores has four problems: (i) less information on "three Rs (reduce, reuse and recycle)" and "chemical substances" than the one on "energy conservation"; (ii) cost for providing environmental information statement; (iii) issues associated with a label and mark placement; (iv) issues associated with energy conservation statement. (2) Improvements are suggested for each of the four problems listed above, and shown are (i) the effectiveness of, and need to promote, a label and mark placement; (ii) cost burden on buyers; (iii) need of active efforts made by businesses and of dissemination of legal regulations to businesses. 展开更多
关键词 Environmental information statement home appliances environmentally-friendly product online store.
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Multiple Mobile Sinks Data Dissemination Mechanism for Large Scale Wireless Sensor Network
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作者 XIE Dongliang WU Xiaojie LI Dan SUN Jia 《China Communications》 SCIE CSCD 2014年第A01期1-8,共8页
WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of... WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations. 展开更多
关键词 ubiquitous information services multiple-mobile sink hierarchical monitoring two-tier grid global agent query-driven
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A MULTIPLE-RECEPTION ACCESS PROTOCOL WITH INTERRUPTIONS WITH MIXED PRIORITIES IN CDMA NETWORKS
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作者 Lu Xiaowen Zhu Jinkang (PCN and SS Laboratory, University of Science and Technology of China, Hefei 230027) 《Journal of Electronics(China)》 2003年第4期241-248,共8页
A novel access protocol called Multiple-Reception Access Protocol (WRAP) and its modification MRAP/WI are proposed. In this protocol, all colliding users with a common code can be identified by the base station due to... A novel access protocol called Multiple-Reception Access Protocol (WRAP) and its modification MRAP/WI are proposed. In this protocol, all colliding users with a common code can be identified by the base station due to the offset of arrival time. Thus they can retransmit access requests under the base station's control. Furthermore new arrivals with higher priority level can interrupt the lower retransmission in order to reduce its access delay although it, increases the lower priority's delay. Simulation results of MRAP and MRAP/WI are given in order to highlight the superior performance of the proposed approach. 展开更多
关键词 MAC Multiple-reception access MRAP/WI Mixed priorities CDMA networks
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