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1.
在小氮肥厂以无烟粉煤加入HM-3粘结剂,制成气化型煤,检测其冷、热态抗压强度、落下强度,型煤性能优于目前工业上使用的石灰碳化煤球。在φ2.26m造气炉内进行造气试验,结果表明,操作平稳,产气量和灰渣含碳量等指标均优于石灰碳化煤球,可作为小氮肥厂造气用块煤的代用原料。  相似文献   

2.
现代大型煤化工企业作为用电大户,其负荷性质决定电网质量。功率因数作为电能质量的一个关键指标,不但影响电网,也影响着电气设备的效率及利用率。本文通过对本公司功率因数较低的原因进行分析,从实用角度提出具体措施,并就其效果予以阐述。  相似文献   

3.
煤岩破坏电磁辐射信号的短时分形模糊滤波   总被引:1,自引:0,他引:1  
撒占友  王恩元 《电波科学学报》2007,22(2):191-195,211
介绍了短时分形滤波的基础理论,在分析煤岩破坏电磁辐射信号噪声特点基础上,提出了煤岩破坏电磁辐射信号的短时分形模糊滤波模型及分形维确定方法,并应用于型煤和原煤两种煤岩破坏电磁辐射信号的滤波处理.结果表明,短时分形滤波法用于煤岩破坏电磁辐射信号滤波是可行的,实现了煤岩破坏电磁辐射信号的自适应模糊控制滤波.  相似文献   

4.
我国控制大气污染的主要任务是减少烧煤的SO_2和NO_x的排放。为减少我国SO_2排放和在2000年把SO_2的年排放量控制在1995年水平,需要做很大的努力和综合治理。应该在燃烧前对原煤进行洗选,以脱除所含的黄铁矿;采用掺有脱硫剂的型煤和增设能脱硫的循环流化床锅炉,易于实现且能更大量减少SO_2排放的是在烧煤发电厂装设烟气脱硫装置。为了减少烧煤设备的烟气脱硫装置的投资和运行费用,应开发新型的低费用脱硫(SO_2)和脱硝(NO_x)技术,例如烟气脱硫剂内循环技术和各种低NO_x煤粉燃烧技术。  相似文献   

5.
中国发展洁净煤技术应覆盖煤炭开发利用的全过程,针对多终端用户,优选实用的先进技术。中国的洁净煤技术是以提高煤炭利用效率、减少污染为目标,以煤炭洗选为源头,以煤炭气化为先导,以煤炭高效洁净燃烧和洁净煤发电为核心的技术体系。框架包括4个领域共12个方面:煤炭加工(选煤,型煤,水煤浆);煤炭高效洁净燃烧(流化床燃烧,高效低污染粉煤燃烧,燃煤联合循环发电);煤炭转化(气化,液化,燃料电池);污染控制(烟气净化,粉煤灰综合利用,矿区污染治理)。  相似文献   

6.
宁夏汝箕沟煤系属我国北方下侏罗统陆相煤系,其下部为白色石英粗砂岩、粉砂岩夹薄煤层,底部第七号煤层又分为上、下两个分层,总厚6.79米,为比较稳定的可采煤层,由光亮、半亮、半暗与暗淡型煤组成,属腐植—腐泥煤类。七号煤的顶底板及煤层中普遍含有白色碳酸盐脉,过去的资金大都认为是充填于裂隙中的方解石脉,垂直层理的为后生脉,平行层理的为同生脉,笔者在研究煤的变质因素时,用电子扫描图像研究了其中同生碳酸盐脉内矿物的微观形貌特征发现:同生的碳酸盐矿物遇盐酸起泡强烈,晶体呈长柱状(参看图片1),其C轴长2(20—60μm、b轴5—12μm,C/b轴比1:3—1:10,柱面(010)、(110)、发育良好,晶面平坦,但(011)发育不好、晶面弯曲不平。根据矿物的化学成分,光性特征、对称形式与形态特征,这种碳酸盐矿物不是方解石,而是文石。  相似文献   

7.
对智能终端自动测试系统进行了描述,对智能终端自动测试系统架构进行了阐述,介绍了对智能终端自动测试系统相关应用案例,并对智能终端自动测试优点进行了分析。  相似文献   

8.
伴随着计算机的普及和相关技术的发展,越来越多的设备对供电质量提出了更高的要求。本文对UPS的发展作了简要介绍,并对UPS的结构及分类进行了阐述,对UPS电池组的保养进行了说明,最后对UPS发展趋势进行了分析。  相似文献   

9.
介绍了电磁脉冲产生的机理,描述了电磁脉冲通过雷达后门耦合途径对兵器和人员的损伤效应,同时对时域有限差分法的应用进行了说明,对雷达后门防护设计思路进行了探讨,并对电磁防护技术的发展提出了看法。  相似文献   

10.
文章首先对光纤接入进行了分析,对FTTX的优势进行了总结,然后对家庭宽带光纤接入技术进行了研究,最后结合实际案例对光纤接入技术进行了探讨,以期对家庭宽带光纤接入技术的推广起到一定的促进作用。  相似文献   

11.
Improved LUT Technique for HPA Nonlinear Pre-Distortion in OFDM Systems   总被引:3,自引:0,他引:3  
In this paper, we focus on the Look-up Table (LUT) technique for the compensation of HPA nonlinear distortion. An improved LUT method is proposed with better performance compared with conventional LUT technique in terms of convergence speeds, BER and total degradation (TD). It can get over 8 dB gain in out-of-band spectrum re-growth suppression and about 0.3 dB BER performance gain than conventional LUT technique with the same iteration times. Also, we propose an actual application of HPA with pre-distorter in OFDM transmitter. Ai Bo was born in Shannxi Province in China on February 7, 1974. He received a BSc. Degree from Engineering Institute of Armed Police Force in 1997, a Master and Dr. degree from Xidian University in 2002 and 2004 in China respectively, and now working as a post dr. in Dept. of E&E, state of key lab. on microwave and digital communications in Tsinghua University in China. He has once participated in the key research project on HDTV in TEEG (Team of Engineering Expert Group) of China. He is an editorial committee member of journal of “Computer Simulations”, “Information and Electronic Engineering”, an IEEE member and a senior member of Electronics Institute of China (CIE). He has published over 60 scientific papers in his research area till now. His current interests are the research and applications of OFDM techniques with emphasis on synchronization and HPA linearization techniques. Yang Zhi-Xing graduated from Tsinghua University, P.R. China in 1970. He is now a Professor and Deputy Director of State Key Lab. on Microwave and Digital Communication at the Department of Electronic Engineering and the Director of the DTV R&D Center in Tsinghua University. As a DTV technical expert for the Chinese government, Professor Yang has also been a member of the DTV standardization Committee of China and a leader of the DTV Standardization Harmonizing Group in Ministry of Information Industry of China. His major research interests include broadband information transmission technologies and DTV broadcasting systems. Pan Chang-Yong received the B.S. and M.S. degrees from the Department of Electronic Engineering in Tsinghua University, P.R. China, in 1996 and 1999, respectively. He is now an associate professor in the Department of Electronic Engineering and a member of the DTV R&D Center in Tsinghua University. His research interests are in the areas of broadband wireless transmission systems and satellite communications. Zhang Tao-Tao was born in Shandong Province in China in 1982, he received BSc. degree from Tsinghua University in 2004 and now pursing his Master degree in Dept. of E&E, state of key lab. on microwave and digital communications in Tsinghua University in China. His research interests is the power amplifier linearization techniques. Wang Yong was born in Shannxi Province in China in 1976. He received a BSc., a Master and a Dr. Degree from Xidian University in China in 1997, 2002 and 2005, respectively, and now is an associate professor in Xidian University. He has once participated in the key research project on HDTV in TEEG (Team of Engineering Expert Group) in China and is an IEEE Member. His interests are broadband multimedia communications. Ge Jian-Hua was born in September, 1961 in JiangSu Province in China. He received the B.Sc., Master and Ph.D. degree from Xidian University in 1982, 1985 and 1989, respectively. He is now the professor in both Xidian University in Xi’an and Shanghai Jiaotong University in Shanghai. He is the senior member of Chinese Electronics Institute. He has won lots of scientific and technical prizes in China and published many papers. His interests are transmission communications and web security.  相似文献   

12.
随着社会的发展,用户对业务质量的需求也日益提高,为此3GPP组织加强了对QoS的研究,在UMTS阶段引入了端到端QoS机制,并在LTE阶段对QoS机制进行了扩展和增强,目前QoS的研究是3GPP研究的一个热点。本文对3GPP移动通信网QoS演进进行了介绍,分析了UMTS和EPC网络的QoS实现机制,并对两种QoS实现机制进行了分析。  相似文献   

13.
中国地区云量和云光学厚度的分布与变化趋势   总被引:1,自引:0,他引:1  
利用最新的1983~2009年国际卫星云气候计划(ISCCP) D2月平均资料集,得到了中国地区总云量、低云量、中云量、高云量与云光学厚度的分布与变化趋势,结果表明:中国总云量和中云量呈现南多北少的分布,青藏高原地区高云量较大而低云量很小;总云量和中云量在东部呈增加趋势,西部呈减小趋势,低云量和高云量在大部分地区呈减小趋势。从不同季节来看,春季和秋季北方总云量增加,西部总云量减小;夏季大部分地区总云量增加,冬季大部分地区总云量减少。云的光学厚度呈现南多北少的分布,且在大部分地区呈增加趋势。同时利用中分辨率成像光谱仪(MODIS)资料分析了2001~2013年间中国不同污染地区总云量与云光学厚度的分布及变化趋势的异同,结果表明:中国不同污染地区云量与云光学厚度呈现不同的分布和变化规律。  相似文献   

14.
This paper demonstrates a technique for controlling the electron emission of an array of field emitting vertically aligned carbon nanofibers (VACNFs). An array of carbon nanofibers (CNF) is to be used as the source of electron beams for lithography purposes. This tool is intended to replace the mask in the conventional photolithography process by controlling their charge emission using the “Dose Control Circuitry” (DCC). The large variation in the charge emitted between CNFs grown in identical conditions forced the controller design to be based on fixed dose rather than on fixed time. Compact digital control logic has been designed for controlling the operation of DCC. This system has been implemented in a 0.5 μm CMOS process. Chandra Sekhar A. Durisety received his B.E. (Hons.) Instrumentation from Birla Institute of Technology and Sciences, Pilani, India in 1997 and his M.S in Electrical Engineering from University of Tennessee, Knoxville in 2002. Since 2003, he has been working towards his Ph.D degree also in Electrical Engineering at Integrated Circuits and Systems Lab (ICASL), University of Tennessee, Knoxville. He joined Wipro Infotech Ltd, Global R & D, Bangalore, India in 1997, where he designed FPGA based IPs for network routers. Since 1999, he was involved in the PCI bridge implementation at CMOS chips Inc, Santa Clara, CA, and the test bench development for Sony’s MP3 player, while at Toshiba America Electronic Components Inc., San Jose, CA. His research interests include multi-stage amplifiers, data converters, circuits in SOI and Floating Gate Devices. Rajagopal Vijayaraghavan received the B.E degree in electronics and communication engineering from Madras University in 1998 and the M.S degree in electrical engineering from the University of Texas, Dallas in 2001.He is currently working towards the Ph.D degree in electrical engineering at the University of Tennessee. His research interest is in the area of CMOS Analog and RF IC design. His current research focuses on LNAs and VCOs using SOI based MESFET devices. Lakshmipriya Seshan was born in Trivandrum, India on April 30, 1979. She received her B.tech in Electronincs & Communication Engg from Kerala University, India in June 2000 and M.S in Electrical Engg from University of Tennessee in 2004. In 2004, she joined Intel Corporation as an Analog Engineer, where she is engaged in the design of low power, high speed analog circuits for various I/O interface topologies. Syed K. Islam received his B.Sc. in Electrical and Electronic Engineering from Bangladesh University of Engineering and Technology (BUET) and M.S. and Ph.D. in Electrical and Systems Engineering from the University of Connecticut. He is presently an Associate Professor in the Department of Electrical and Computer Engineering at the University of Tennessee, Knoxville. Dr. Islam is leading the research efforts of the Analog VLSI and Devices Laboratory at the University of Tennessee. His research interests are design, modeling and fabrication of microelectronic/optoelectronic devices, molecular scale electronics and nanotechnology, biomicroelectronics and monolithic sensors. Dr. Islam has numerous publications in technical journals and conference proceedings in the areas of semiconductors devices and circuits. Benjamin J. Blalock received his B.S. degree in electrical engineering from The University of Tennessee, Knoxville, in 1991 and the M.S. and Ph.D. degrees, also in electrical engineering, from the Georgia Institute of Technology, Atlanta, in 1993 and 1996 respectively. He is currently an Assistant Professor in the Department of Electrical and Computer Engineering at The University of Tennessee where he directs the Integrated Circuits and Systems Laboratory (ICASL). His research focus there includes analog IC design for extreme environments (both wide temperature and radiation immune), multi-gate transistors and circuits on SOI, body-driven circuit techniques for ultra low-voltage analog, mixed-signal/mixed-voltage circuit design for systems-on-a-chip, and bio-microelectronics. Dr. Blalock has co-authored over 60 published refereed papers. He has also worked as an analog IC design consultant for Cypress Semiconductor Corp. and Concorde Microsystems Inc.  相似文献   

15.
A major issue in the design and operation of ad hoc networks is sharing the common spectrum among links in the same geographic area. Bandwidth allocation, to optimize the performance of networks in which each station can converse with at most a single neighbor at a time, has been recently studied in the context of Bluetooth Personal Area Networks. There, centralized and distributed, capacity assignment heuristics were developed, with applicability to a variety of ad hoc networks. Yet, no guarantees on the performance of these heuristics have been provided. In this paper, we extend these heuristics such that they can operate with general convex objective functions. Then, we present our analytic results regarding these heuristics. Specifically, we show that they are β-approximation (β<2) algorithms. Moreover, we show that even though the distributed and centralized algorithms allocate capacity in a different manner, both algorithms converge to the same results. Finally, we present numerical results that demonstrate the performance of the algorithms. Randeep Bhatia received the Ph.D. degree in Computer Science from University of Maryland, the M.S. degree in Mathematics and Computer Science from University of Illinois at Chicago and the B.Tech. degree in Computer Science and Engineering from Indian Institute of Technology, Delhi. He is currently with the High Speed Networks Research Department at Bell Labs, Lucent technologies, working on network design, traffic engineering and scheduling algorithms. His current research interests are in the area of QoS for multimedia services in wireless data networks. Adrian Segall received the B.Sc. and M.Sc. degrees in electrical engineering from the Technion, Israel Institute of Technology in 1965 and 1971, respectively, and the Ph.D. degree in electrical engineering with a minor in statistics from Stanford University in 1973. After serving active duty in the Israel Defense Forces, he joined in 1968 the Scientific Department of Israel’s Ministry of Defense. From 1973 to 1974 he was a Research Engineer at System Control Inc., Palo Alto, CA and a Lecturer at Stanford University. From 1974 to 1976 he was an Assistant Professor of Electrical Engineering and Computer Science at the Massachusetts Institute of Technology. From 1987 to 1998 he was on the faculty of the Department of Computer Science at the Technion. He is presently Benjamin Professor of Computer-Communication Networks in the Department of Electrical Engineering, Technion, Israel Institute of Technology. From 1982 to 1984 he was on leave with the IBM T.J.Watson Research Center, Yorktown Heights, NY. He held visiting positions with IBM, AT&T and Lucent Bell Labs. His current research interests are in the area of optical networks, wireless, sensor and ad-hoc networks. Dr. Segall is an IEEE Fellow and has served in the past as Editor for Computer Communication Theory of the IEEE Transactions on Communications, Editor for the IEEE Information Theory Society Newsletter and Senior Editor for the IEEE Journal on Selected Areas in Communications. He was selected as an IEEE delegate to the 1975 IEEE-USSR Information Theory Workshop, and is the recipient of the 1981 Miriam and Ray Klein Award for Outstanding Research and of the 1990 Taub Award in Computer Science. Gil Zussman received the B.Sc. degree in Industrial Engineering and Management and the B.A. degree in Economics (both summa cum laude) from the Technion—Israel Institute of Technology in 1995. He received the M.Sc. degree (summa cum laude) in Operations Research from Tel-Aviv University in 1999 and the Ph.D. degree in Electrical Engineering from the Technion—Israel Institute of Technology in 2004. Between 1995 and 1998, he served as an engineer in the Israel Defense Forces. He is currently a Postdoctoral Associate in the Laboratory for Information and Decision Systems in MIT. His current research interests are in the area of ad hoc and sensor networks. In particular, he is interested in energy efficient protocols, medium access control protocols, and personal area networks. Gil received the Knesset (Israeli Parliament) Award for distinguished students, the Best Student Paper Award at the IFIP-TC6 Networking 2002 Conference, and the IEEE Communications Magazine Best Paper Award at the OPNETWORK 2002 Conference. In 2004 he received the Marie Curie Outgoing International Fellowship and the Fulbright Fellowship.  相似文献   

16.
随着时代的发展,国家对人才的需求量不断增加,并且对人才培养的要求越来越高。高校作为人才输出的重要基地,人们对高等教育的重视程度不断加深,尤其是近年来高校在发展的过程中其规模也在不断的扩展,导致固定资产管理中的一些问题逐渐凸显出来。本文就固定资产管理中存在的问题进行分析,进一步探讨云计算技术在高校固定资产管理中的应用。  相似文献   

17.
In this paper, we develop an analytical model to evaluate the delay performance of the burst-frame-based CSMA/CA protocol under unsaturated conditions, which has not been fully addressed in the literature. Our delay analysis is unique in that we consider the end-to-end packet delay, which is the duration from the epoch that a packet enters the queue at the MAC layer of the transmitter side to the epoch that the packet is successfully received at the receiver side. The analytical results give excellent agreement with the simulation results, which represents the accuracy of our analytical model. The results also provide important guideline on how to set the parameters of the burst assembly policy. Based on these results, we further develop an efficient adaptive burst assembly policy so as to optimize the throughput and delay performance of the burst-frame-based CSMA/CA protocol. Kejie Lu received the B.E. and M.E. degrees in Telecommunications Engineering from Beijing University of Posts and Telecommunications, Beijing, China, in 1994 and 1997, respectively. He received the Ph.D. degree in Electrical Engineering from the University of Texas at Dallas in 2003. In 2004 and 2005, he was a postdoctoral research associate in the Department of Electrical and Computer Engineering, University of Florida. Currently, he is an assistant professor in the Department of Electrical and Computer Engineering, University of Puerto Rico at Mayagüez. His research interests include architecture and protocols design for computer and communication networks, performance analysis, network security, and wireless communications. Jianfeng Wang received the B.E. and M.E. degrees in electrical engineering from Huazhong University of Science and Technology, China, in 1999 and 2002, respectively, and the Ph.D. degree in electrical engineering from University of Florida in 2006. From January 2006 to July 2006, he was a research intern in wireless standards and technology group, Intel Corporation. In October 2006, he joined Philips Research North America as a senior member research staff in wireless communications and networking department. He is engaged in research and standardization on wireless networks with emphasis on medium access control (MAC). Dapeng Wu received B.E. in Electrical Engineering from Huazhong University of Science and Technology, Wuhan, China, in 1990, M.E. in Electrical Engineering from Beijing University of Posts and Telecommunications, Beijing, China, in 1997, and Ph.D. in Electrical and Computer Engineering from Carnegie Mellon University, Pittsburgh, PA, in 2003. Since August 2003, he has been with Electrical and Computer Engineering Department at University of Florida, Gainesville, FL, as an Assistant Professor. His research interests are in the areas of networking, communications, multimedia, signal processing, and information and network security. He received the IEEE Circuits and Systems for Video Technology (CSVT) Transactions Best Paper Award for Year 2001, and the Best Paper Award in International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks (QShine) 2006. Currently, he serves as the Editor-in-Chief of Journal of Advances in Multimedia, and an Associate Editor for IEEE Transactions on Wireless Communications, IEEE Transactions on Circuits and Systems for Video Technology, IEEE Transactions on Vehicular Technology, and International Journal of Ad Hoc and Ubiquitous Computing. He is also a guest-editor for IEEE Journal on Selected Areas in Communications (JSAC), Special Issue on Cross-layer Optimized Wireless Multimedia Communications. He served as Program Chair for IEEE/ACM First International Workshop on Broadband Wireless Services and Applications (BroadWISE 2004); and as a technical program committee member of over 30 conferences. He is Vice Chair of Mobile and wireless multimedia Interest Group (MobIG), Technical Committee on Multimedia Communications, IEEE Communications Society. He is a member of the Best Paper Award Committee, Technical Committee on Multimedia Communications, IEEE Communications Society. Yuguang Fang received a Ph.D. degree in Systems Engineering from Case Western Reserve University in January 1994 and a Ph.D. degree in Electrical Engineering from Boston University in May 1997. He was an assistant professor in the Department of Electrical and Computer Engineering at New Jersey Institute of Technology from July 1998 to May 2000. He then joined the Department of Electrical and Computer Engineering at University of Florida in May 2000 as an assistant professor and got an early promotion to an associate professor with tenure in August 2003 and to a full professor in August 2005. He has published over 200 papers in refereed professional journals and conferences. He received the National Science Foundation Faculty Early Career Award in 2001 and the Office of Naval Research Young Investigator Award in 2002. He has served on several editorial boards of technical journals including IEEE Transactions on Communications, IEEE Transactions on Wireless Communications, IEEE Transactions on Mobile Computing and ACM Wireless Networks. He have also been actively participating in professional conference organizations such as serving as The Steering Committee Co-Chair for QShine, the Technical Program Vice-Chair for IEEE INFOCOM’2005, Technical Program Symposium Co-Chair for IEEE Globecom’2004, and a member of Technical Program Committee for IEEE INFOCOM (1998, 2000, 2003–2007). He is a senior member of the IEEE.  相似文献   

18.
陕西省平利县朱家院碱性岩中易解石矿物学研究   总被引:1,自引:0,他引:1  
利用电子探针分析,背散射形貌分析和元素面分布及定量分析等手段,对陕西省平利县朱家院碱性岩中的易解石进行了研究。结果表明:朱家院碱性岩中易解石主要有不规则粒状和细脉状两种产状,粒状易解石粒径在10~100μm,常与金红石、钠铁闪石等矿物伴生;脉状易解石切割脉状褐帘石,显示脉状易解石为后期形成。两种易解石中Nb,Ta,Ti,Ce,Nd等元素分布均均匀;稀土含量相对较高,有富轻稀土,贫重稀土的特征,其中Ce和Nd的含量高。脉状易解石中Nb,Ta含量高于粒状易解石,Ti含量低于后者;根据成分确定,脉状易解石为铌易解石,粒状易解石为易解石-铌易解石过渡型。  相似文献   

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