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Search Results: 1 - 10 of 61356 matches for " 倪梁方 "
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从统计数据浅析信息论与编码的教与学
The Fundamental Analysis for Teaching and Studying of Information Theory and Coding Based on Statistics*
 [PDF]


Advances in Education (AE) , 2012, DOI: 10.12677/AE.2012.24015
Abstract:

信息论与编码是通信工程的核心专业基础课之一。针对该课程需学生兼具广泛数学理论与工程实际背景的特点和学生的现状,从理论教学的目的和内容出发,探讨了由点而面、书本知识结合信息科学发展的教学方法。统计数据表明:授课条理清晰、逻辑推理严谨、多与学生交流,把握学生的学习动态,促使教与学互动是教学效果不断提高的关键。

The Information Theory and Coding is one of the core professional basic courses to the major of communication engineering. From points to face, the teaching methods of book knowledge combined with the development of information science, based on the purpose and content of the theoretical teaching and studying, are analyzed according to the characteristics that the students must be with both wide range of mathematical theory and engineering background and the status of the students. The statistics show that the key to continu- ously improve teaching effectiveness is the clear teaching, strictly logical reasoning, exchanging with students, grasping the dynamics of student learning and promoting the teaching and learning interaction.

 

无线多跳网络中分簇算法的研究进展和未来前瞻
The Research Progress and Future Perspective of Clustering Algorithm for Wireless Multi-Hop Network
 [PDF]

高莹, , 陈建建
Open Journal of Nature Science (OJNS) , 2014, DOI: 10.12677/OJNS.2014.24008
Abstract:
受干扰、衰落、多径、路径损耗和阴影等因素制约,当移动Ad-hoc网络中两个节点间的距离较远时,两者间通过单跳方式无法保证高质量的可靠通信。若在该网络中通过节点分簇建立多跳虚拟天线阵列,实现协同分集,就可以有效应对上述不利影响。本文从静态和动态两个方面,在研究了基于信噪比和基于维特比算法分簇方案的基础上,进一步探讨了动态分簇对利用编码存储互信息的需求,详细分析了分簇方案的特性,并依据现阶段分簇技术在理论和实践两方面取得的主要成果及二者之间的本质联系,对未来的研究和探索提出了建议。
The extremely poor performance owns to interference, attenuation, multi-path, path loss and shadowing. It makes it impossible to guarantee the quality and the reliability of the single hop communication between two nodes with long distance in mobile Ad-hoc network. The cooperative diversity could be achieved to counterbalance the above affects, once the multi-hop virtual mul-ti-antenna system was implemented with the aid of clustering the nodes. In terms of the static and dynamic clustering, this paper analyzed the characteristics of clustering schemes, according to the exploration of the mutual information accumulation with the aid of distributed space-time coding for dynamic clustering, in the light of the investigation of clustering schemes based on signal to noise ratio and Viterbi algorithm. On the basis of current achievement on theory and practice of clustering techniques and their essential relation, the proposals for future research and develop-ment were presented.
夫西地酸有关物质的色谱-质谱结构鉴定
,悦泠,王璐,杭太俊,宋敏
- , 2018,
Abstract: 采用色谱-质谱联用技术鉴定夫西地酸的有关物质。采用Agilent Extend-C18色谱柱(150 mm×4.6 mm,3.5 μm),以甲醇-乙腈-水-甲酸为流动相梯度洗脱,对夫西地酸有关物质进行分离;采用电喷雾正离子化-飞行时间质谱法(ESI-TOF/MS)测定各有关物质的相对分子质量和元素组成,三重四极杆串联质谱(ESI-MS/MS)测定子离子特征,解析鉴定有关物质的结构。在所建立的条件下,夫西地酸及其有关物质分离良好,检测并鉴定出19个主要有关物质,其中11个为欧洲药典规定的已知有关物质,8个为未知有关物质。色谱-质谱联用技术能有效地分离鉴定夫西地酸中的有关物质,为其存储条件和质量控制提供参考依据。
To identify the related substances of fusidic acid by LC-MS, separation was performed on an Agilent Extend-C18 column(150 mm × 4. 6 mm, 3. 5 μm)by linear gradient elution with a mobile phase consisting of methanol, acetonitrile and formic acid. Electrospray positive ionization high resolution TOF/MS was used for the determination of the accurate mass and elemental composition of parent ions of the related substances; triple quadrupole tandem mass was employed for the mass spectra determination of the product. The structures of the related substances were then figured out through the elucidation of the fragment ions. Fusidic acid and its related substances were adequately separated under the established HPLC conditions. Nineteen major related substances of fusidic acid were detected and speculated by hyphenated techniques. Eleven of them were recorded in European Pharmacopoeia, while the others have not been previously reported. The established LC-MS method is effective for the separation and identification of the related substances of fusidic acid and the results are useful for its storage conditions and quality assurance
SDR-Based Blind Channel Estimation of Time-varying OFDM Systems
基于半定松弛方法的时变OFDM系统盲信道估计

Fang Cheng-zhi Du Si-dan Ni Liang-fang,
承志
,都思丹,

电子与信息学报 , 2008,
Abstract: Some Quadratic Programs (QP) have been presented for the blind channel estimation and signal detection of the time-varying OFDM systems. In this paper a method is proposed to turn the QP problem into the optimization of a Semi-Definite Program (SDP) based on the Semi-Definite Relaxation (SDR) technique. Compared to the original QPs which reach the optimal solution with exponential complexity, the SDP could be solved efficiently in polynomial time. In order to reduce the complexity involved in the transform from the solution of the SDPs to the solution of the original QPs, the correlation property of the OFDM time-frequency response between adjacent subchannels or time-slots is exploited to devise a novel randomization strategy. The simulation proves the effectiveness of the new method.
现象学的方法特征:关于现象学与人类学、心理学之间关系的思考

安徽大学学报(哲学社会科学版) , 2009,
Abstract: 可以通过揭示现象学与人类学和心理学的关系来说明现象学的特殊领域和特殊方法。具体地说,从现象学与人类学的关系来说明现象学的先验还原方法及其必要性;从现象学与心理学的关系来说明本质还原(本质直观、观念直观)方法及其必要性。如果将现象学看作某种意义上的心而上学,那么它一方面有别于实证心理学,另一方面也有别于思辨心理学和超心理学。
语言哲学的现象学视角――胡塞尔与马尔梯的思想史关联

安徽大学学报(哲学社会科学版) , 2014,
Abstract: 胡塞尔与马尔梯的最根本分歧是在含义论(Bedeutungslehre)方面,这是由于他们各自处在不同的语言哲学立场上所导致的。胡塞尔通过对洛采(Lotze)和鲍尔查诺(Bolzano)的柏拉图理解而形成的直观的观念论,恰好构成在柏拉图主义的弗雷格与心理主义的马尔梯之间的一个区域,因此胡塞尔也会受到来自他们两方面的批评,而他们各自的背后站着洛采和布伦塔诺(Brentano)。胡塞尔认识论中的观念论和语言学中的含义论都具有一个明显的现象学特点它们主张作为纯粹含义的观念的存在,同时主张这个存在是可以被直观到的,是可以显现的。这就是胡塞尔早期“直观的观念论”(Idealismus)的基本意涵。
砌体墙的破坏准则及剪压复合作用下抗剪承载力
,建国
工程力学 , 2012, DOI: 10.6052/j.issn.1000-4750.2010.12.0943
Abstract: 砌体墙在竖向压力和平面内水平剪力复合作用下的破坏准则是确定砌体抗剪承载力的重要依据。通过对比分析,推导出基于最大主应力理论、剪摩理论、Mohr理论和变形能理论的适合于砌体在剪压复合作用下的破坏准则。考虑到微元体与宏观墙模型的差别,建立了相应于各种破坏准则的砌体抗剪承载力计算公式。并将公式的计算结果与收集的111片普通粘土砖砌体墙片的试验结果进行了对比分析,得到了常用多层砌体房屋墙的抗剪承载力计算公式。
WO3/(TiO2-SiO2)催化剂的表面分散状态及催化性能的研究

分子催化 , 2006,
Abstract: 用气相流动吸附法制备复合载体,用浸渍法制备WO3/(TiO2-S iO2)催化剂.应用LRS和TPR技术研究WO3在复合载体TIO2-S iO2表面的分散状态,发现TiO2在S iO2表面的分散可增强WO3与载体之间的相互作用,提高WO3在载体表面的分散阈值.另外TPR实验证明,TiO2的存在不仅大大改善WO3的分散状态,而且使WO3在TiO2-S iO2的还原温度升高,WO3与载体之间的作用增强.负载于经TiO2调变的S iO2上的催化剂其HDS、HYD、BHD活性高于负载于单纯S iO2上的催化剂的活性.
中华鲟吻部腹面罗伦氏囊结构与功能的研究

海洋与湖沼 , 1996,
Abstract: 于1993年12月-1994年9月,从宜昌葛洲坝工程总局中华鲟人工繁殖研究所获中华鲟实验材料128尾,通过扫描电镜(包括冷冻断裂扫描电镜)、透射电镜及行为学实验方法,研究中华鲟吻部腹面罗伦氏囊结构及其功能作用。结果表明,中华鲟吻部腹面存在大量罗伦氏囊。触须表面无罗伦氏囊而仅存在很少量味蕾。中华鲟罗伦氏囊由开孔、管道和壶腹三部分组成,壶腹具有梨形单纤毛电觉细胞。中华鲟对微弱电刺激异常敏感,且对较小电刺激物有摄食反应,而对水蛆蚓汁化学刺激则没有反应。为此可以认为中华鲟吻部腹面罗伦氏囊是电觉器官,在中华鳄觅食活动中起作用,而中华鲟触领味觉在觅食中作用不大。
鳜捕食行为的研究

海洋与湖沼 , 1995,
Abstract: 于1990年8月 - 1992年4月,在实验室内通过特定感官消除或抑制方法与单一感官刺激方法研究鳜捕食行为中几种相关感觉的作用及其相互关系。结果表明,鳜主要依靠视觉和侧线捕食,其精物的视觉特征是不连续运动和梭形形状演侧线主要对猎物的低频振动起反应;鳜首先依靠视觉捕食,仅在视觉受到限制时才依靠侧线捕食;嗅觉在鳜捕食中作用不大,味觉在鳜吞咽食物过程中起很大作用。由于鳜主委依靠仅对运动刺激敏感的视觉和侧线捕食猎物,且需对猎物窥视一段时间后才突发攻击,因而鳜一般不摄食人工饲料。
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