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OSCILLATION OF THIRD ORDER DELAY DIFFERENTIAL EQUATIONS WITH IMPULSES

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Annals of Differential Equations 2007年第4期23卷 450-460页

作者： liu Xiuxiang Xu Zhiting school of mathematical Sciences South China Normal University Guangzhou 510631

In this paper we study the oscillation and asymptotic behavior of third order delay differential equations with impulses. Some new sufficient conditions which guarantee that every solution is oscillatory or converges ... 详细信息

关键词： oscillation impulses third order delay differential equations

Research on Quartz Ceramic Crucible Wastes Applied in Jewelry Casting

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Research on Quartz Ceramic Crucible Wastes Applied in Jewelr...

A NEW CALL CONTROL SCHEME OF PUSH-TO-TALK SYSTEM

2.11 IEEE International Conference on Waste Recycling,Ecology and Environment(ICWREE 2.11)

作者： Zhifan XU1 Yongheng ZHOU1* Shaoxing CHEN2.Keya SHEN2.Chang CHAN2.1 school of Photo Electronic Science and Technology {2. guangzhou china 2.Jewelry Institute of guangzhou Panyu Polytechnic guangzhou china

The method of production of cristobalite was based on the use of quartz ceramic crucible wastes as the basic raw material. The gypsum casting material was prepared by mixing cristobalite powder, gypsum and silica powder. Calorific properties were tested and the results showed that when the content of cristobalite was more than 50% , the gypsum casting material showed obvious cracks, which was removed into the air from resistance furnace at 600℃ after the baking process was over. The gypsum casting material showed better therma crack resistance, when 0.3 g glass fiber were added into per 100 g mixed powder, with the content of cristobalite controlled between 40%-30%. In 300-600℃, about 0.4% thermal expansion occurred which effectively compensated for the cooling contraction of jewelry alloy making the casting sample meet production needs.

关键词： quartz ceramic crucible cristobalite therma expansion jewelry casting

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Journal of Electronics(china) 2010年第6期27卷 790-794页

作者： Cao Peng Chen Xiaojian school of Physics ＆ Telecommunication Engineering Science South China Normal University Guangzhou 510563 China

For Push-To-Talk (PTT) system based on Public Mobile Data Network (PMDN), the end-to-end time delay is the key aspect of the user's experience. The Push-Over-Cellular (POC) scheme defined by Open Mobile Alliance (OMA) is based on the VoIP phone model and use SIP protocol as the call control scheme. The call setup time delay in SIP may reach to several seconds, which is unac-ceptable for the PTT service. In this paper, we provide a new call control scheme for PTT system based on PLMN network. By combining the apriority knowledge of PTT call model and the priority control scheme, we encapsulate the signaling message and the voice data into a same data packet, when the user push the button, the voice and the call control signaling are sent to the server at the same time. So the long time delay of call setup procedure of POC scheme can be eliminate. The end-to-end call delay can be decreased significantly. The experiment result based on the commercial CDMA2.00 1X network of china Unicom shows that the call delay can be decreased to 600 ms, which approach to the traditional trunk communication system's requirement.

关键词： Call control Push-To-Talk (PTT) Trunk communications

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聚光太阳能吸热管的吸热传热特性

太阳能学报 2010年第3期31卷 328-332页

作者：陆建峰丁静文玉良杨建平中山大学工学院广州510006 华南理工大学传热强化与过程节能教育部重点实验室广州510640

基于太阳能选择性吸收涂层的辐射性能,建立聚光太阳能吸热管光热耦合传输的数理模型,理论研究聚光太阳能吸热管的吸热传热特性。研究表明,吸热管壁温度随着聚光能流密度增加而线性升高,而吸热效率在中等聚光能流密度时达最大值。太阳能... 详细信息

基于太阳能选择性吸收涂层的辐射性能,建立聚光太阳能吸热管光热耦合传输的数理模型,理论研究聚光太阳能吸热管的吸热传热特性。研究表明,吸热管壁温度随着聚光能流密度增加而线性升高,而吸热效率在中等聚光能流密度时达最大值。太阳能选择性吸收涂层性能对吸热传热有重要影响,具有低红外发射系数涂层的系统吸热效率明显较高,而红外辐射能量损失率则在中等聚光能流密度时最小。管内强迫对流可以显著提高吸热管效能,吸热效率随流速增加而提高,而管壁温度则显著下降。

关键词：吸热管太阳能选择性涂层吸热效率对流换热

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CAT初始阶段被试能力估计方法改进探究

心理科学 2010年第6期33卷 1470-1472页

作者：简小珠张敏强华南师范大学心理应用研究中心广州510631 井冈山大学教育学院吉安343009

在CAT初始阶段被试作答的信息较少,对被试能力进行合理和稳健的估计比较困难。本文设计CAT测试过程的代表性测验样例,使用不同能力估计方法比较CAT初始阶段的被试能力估计情况。在单参数模型下,在题量较少时,EAPE-N(0,0.5)方法的能力估... 详细信息

在CAT初始阶段被试作答的信息较少,对被试能力进行合理和稳健的估计比较困难。本文设计CAT测试过程的代表性测验样例,使用不同能力估计方法比较CAT初始阶段的被试能力估计情况。在单参数模型下,在题量较少时,EAPE-N(0,0.5)方法的能力估计的合理性和稳健性要相对优于MLE、EAPE-N(0,2.、EAPE-N(0,1)方法。在CAT测试过程中可以先使用先验分布方差较小的EAPE方法进行估计,随着测试题量增加,逐步增大EAPE方法的先验分布方差,并可以和a分层选题策略结合起来使用。

关键词： CAT 极大似然估计期望后验估计期望后验估计调整方法

First Diels-Alder Addct of [60]Fullerene with a Piperidinoxanthate

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First Diels-Alder Addct of [60]Fullerene with a Piperidinoxa...

Identification of Genes Related to Nasopharyngeal Carcinoma with the Help of Pathway-based Networks

第三届全国有机化学学术会议

作者： wen, li-Jun ZENG, He-Ping ( Department of Chemistry, {2., guangzhou 510631)

＜正＞ In the search for intramolecular energy and electron transfer phenomena in [ 60 ] fullerene donor-containing molecules, some electron donor fragments have been covalently linked to the fullerene core. Only in very few cases has reliable evidence of thermal or photoinduced intramolecular electron transfer processes been reported. With the aim of promoting an intramolecular electron transfer we sought to develop a novel type of 6-chloro-phenazine derivative of [60] fullerene in which the 6-chloro-phenazine core is directly attached by two a -bonds to the

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 900-910页

作者： Hui li~1 Cai-Ping REN~1* Xiao-Jun TAN~2.Xu-Yu YANG~1 Hong-Bo ZHANG~1 wen ZHOU~1 Kai-Tai YAO~1 1 Cancer Research Institute,Xiangya {2. of Medicine,Central south university,Changsha 410078,china 2.Reproductive and Stem Cell Engineering Institute,Xiangya {2. of Medicine,Central south university,Changsha 410078,china CancerResearchInstitute XiangyaSchoolofMedicineCentralSouthUniversityChangsha410078China ReproductiveandSternCellEngineeringInstitute XiangyaSchoolofMedicineCentralSouthUniversityChangsha410078China

cDNA microarray is a powerful tool to analyze simultaneously the expression levels of tens ofthousands of *** with normal nasopharynx (NP) tissues,2.10 genes were highly differentiallyexpressed in nasopharyngeal carcinoma (NPC) tissues detected by cDNA *** signal pathwayis widely used to describe the complex relationship between genes,a pathway-based network was con-structed to visua{2.ze the connection between the genes obtained from microarray data in this *** the targeted genes that may have more important influence on this gene network with statisticalmethods and found that some genes might have significant influence on this network,especially Ras-relatednuclear protein (RAN),carboxyl ester {2.pase (CEL),v-rel reticuloendothe{2.osis viral oncogene homolog A(RELA) *** verify the results from pathway-based selection,reverse transcription-polymerase chainreaction (RT-PCR) and real-time RT-PCR were performed to detect the expression levels of RAN,CEL andRELA genes and it was found that the RAN and CEL genes were significantly up-regulated in more than 80%of NPC *** further elucidate the function of the RAN gene,RAN expression was specifically sup-pressed in a 5-8F NPC cell {2.ne by RNA interference (RNAi).As expected,the depletion of RAN couldeffectively block the pro{2.feration of tumor ***,our study may open up a new way to analyze thevast microarray data.

关键词： nasopharyngeal carcinoma microarray real-time PCR RNA interference Ras-related nuclear protein (RAN)

Synthesis and properties investigation on Zn metal complex based on 8-hydroxyquinoline derivatives

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Synthesis and properties investigation on Zn metal complex b...

A CONJECTURE CONCERNING THE HADAMARD PRODUCT OF INVERSE M-MATRICES

第11届全国发光学学术会议

作者： WEI Jie-ping ZENG He-ping~* (south china normal university,guangzhou 510631,{2. Institute of Functional Molecule,school of Chemistry,south {2. university of Technology,guangzhou 510641,{2.)

Since Tang et al first used 8-hydroxyquinoline aluminium(Alq)complex as an emissive and electron transport material(ETM)for double Organic light emitting devices(OLED)in 1987, organic material based on 8-hydroxyquinoline for OLED have attracted extensive interest for their high efficiency and potentially low production *** organic material for ETM ought to be high quantum efficiency,thermally robust emissive,readily processible,improved stability and durability of *** order to tune its emission colour and reduce the production technics, three zinc complexes of 8-hydroxyquinoline derivatives were designed and synthesized for ETM and hole transport material in *** novel compounds were determined by IR,H NMR, MS,UV-visible *** DSC-TG result shew that all the complexes were thermally stable with less than 17％ weight-loss on the temperature 600℃ under *** fluorescence emission spectra was shown in figure *** the complexes had broad *** 1 and 2.almost had the same emission maximum in the range of 500～800 *** 3 had emission maximum that was blue shift 40 nm compared with Complexes 1 and *** the emission wavelength of them was red shifted compared with zinc complex of 2.methyl-quinolin-8-ol.

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Numerical Mathematics A Journal of Chinese Universities(English Series) 2000年第S1期9卷 113-114页

作者： Zhou Yuzhong(Dept.of Math.,south china normal university,guangzhou 510631,PRC)

1 IntroductionFor an n×n matrix A which is an inverse M-matrix,*** in [1]conjecturedthat the Hadamard product A·A is an inverse of an *** have checked hisconjecture without failure on Ultrametric matrices and inverse of MMA-matrices,Uni-pathicmatrices and the Willongby inverse ***-Ying Wang et ***[2.haveinvestigated Triangular inverse M-matrices which are closed under the Hadamard *** linzheng,sun Weiwei and li wen in[3]presented a more general

关键词： Wang A CONJECTURE CONCERNING THE HADAMARD PRODUCT OF INVERSE M-MATRICES Zhang more