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Secure coverage-preserving node scheduling scheme using energy prediction for wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2010年第5期17卷 100-108页

作者： LI Zhi-yuan,WANG Ru-chuan. College of Computer,nanjing university of Posts and Telecommunications,nanjing 2.0003.China [a] College of Computer Nanjing University of Posts Telecommunications Nanjing 210003 China

With the fast development of the micro-electro-mechanical systems （MEMS）,wireless sensor networks （WSNs） have been extensively *** of the studies focus on saving energy consumption because of restricted energy supply in ***-based node scheduling scheme is commonly considered as one of the most energy-efficient ***,it is not always so efficient especially when there exist hot spot and network attacks in *** this article,a secure coverage-preserved node scheduling scheme for WSNs based on energy prediction is proposed in an uneven deployment *** scheme is comprised of an uneven clustering algorithm based on arithmetic progression,a cover set partition algorithm based on trust and a node scheduling algorithm based on energy *** results show that network lifetime of the scheme is 3.0 rounds longer than that of other scheduling ***,the scheme can keep a high network coverage ratio during the network lifetime and achieve the designed objective which makes energy dissipation of most nodes in WSNs balanced.

关键词： wireless sensor networks secure energy-efficient coverage node scheduling cover set energy prediction

Methyl Jasmonate Reduces Chilling Injury and Maintains Postharvest Quality in Peaches

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Agricultural sciences in China 2003年第11期2卷 1246-1252页

作者： FENG Lei, ZHENG Yong-hua, ZHANG Yan-fen, WANG Feng ZHANG Lan and LU Zhao-xin(College of Food science and technology, {2. Agricultural {3., {2. 2.0095 , P.R.China) College of Food science and technology Nanjing Agricultural University Nanjing 210095 P. R. China

Zhaohui peaches(Prunus persica Batsch)were treated with 0(CK), 1, 10 or 100 μmol L-1 methyl jasmonate(MeJA)vapor at 2.℃ for 2. h before stored at 0℃ for 3. d. The untreated fruits showed chilling injury(CD symptoms after 4 wk of storage, as indicated by increased fruit firmness and reduced ex-tractable juice, which is referred as leatheriness. Treatment with 1 and 10 μmol L-1 MeJA promoted normal ripening and softening, maintained higher levels of extractable juice, titratable acidity, pectinesterase(PE)and polygalacturonase(PC)activities, inhibited increases in fruit fresh weight loss, decay incidence, electrolyte leakage and MDA content, and improved color development, thereby preventing chilling injury symptoms development and maintaining edible quality. MeJA treatment also delayed the climacteric rise in respiratory rate, but promoted ethylene production during the later period of cold storage, suggesting that ethylene may involve in CI development of peaches. These results indicate that 1 and 10 μmol L-1 MeJA treatments could be used to reduce CI development and decay incidence in peaches.

关键词： Peach fruit Chilling injury Leatheriness Quality Methyl jasmonate

基于Plug-in的WWW安全认证系统研究

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系统工程与电子技术 2004年第6期26卷 811-813页

作者：刘世栋杨林王小伟王建新南京解放军理工大学通信工程学院江苏南京210007 北京总参第61研究所北京100039

插件(Plug in)结构能使软件动态寻找和加载特定代码模块,被越来越广泛地采用。在基于B/S体系结构中采用Plug in技术可以有效地增强浏览器功能。从基于Web的安全认证出发,研究了浏览器中Plug in程序设计方法,提出了浏览器中采用Plug in... 详细信息

插件(Plug in)结构能使软件动态寻找和加载特定代码模块,被越来越广泛地采用。在基于B/S体系结构中采用Plug in技术可以有效地增强浏览器功能。从基于Web的安全认证出发,研究了浏览器中Plug in程序设计方法,提出了浏览器中采用Plug in技术实现基于IC卡的用户身份认证方案,通过对服务器资源设定和Web页面改造,实现了用户对服务器Web资源访问控制功能。

关键词：网络安全认证访问控制插件

Glacial atmospheric CO_(2. decline in association with decrease of marine sedimentary phosphorus

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science China Earth sciences 2006年第3期49卷 322-330页

作者： WENG Huanxin1, ZHANG Xingmao1, WU Nengyou2. WANG Ying1, CHEN Lihong1, ZHONG Hexian2.& QIN Yachao1 1. institute of Environment & Biogeochemistry, Zhejiang university, Hangzhou {2.002., China 2. Guangzhou Marine Geological Survey, CGS, MLR, Guangzhou 510760, China 1. institute of Environment & Biogeochemistry Zhejiang University Hangzhou 310027 China 2. Guangzhou Marine Geological Survey CGS MLR Guangzhou 510760 China

The environmental and biogeochemical information extracted from the sediments col- lected from the northern shelf of the South China Sea shows that terrigenous inputs of phosphorus into the sea remained relatively constant, and the variation of phosphorus contents at different depths was caused by climatic and environmental changes. The findings also suggest that the vertical varia- tion of phosphorus content was opposite to those of calcium carbonate and cadmium, and the func- tional correlation between CO2.and PO43. in seawater was given by calculating the chemical equilib- rium, indicating that the accumulation of marine sedimentary phosphorus may have something to do with the variation of atmospheric CO2. The decreased phosphorus accumulation as well as the cor- respondingly-increased calcium carbonate content might be one of key factors causing glacial at- mospheric CO2.decline.

关键词： sedimentary phosphorus, calcium carbonate, atmospheric CO2. northern shelf of the South China Sea, biogeochemistry.

On Some Species Extinction in the Nonautonomous n -Competing Pecies Systems

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Systems science and Systems Engineering 1999年第3期9卷 267-276页

作者： CHEN Bo\|shan\+1\ \ LIU Yong\|qing\+2.1. Department of Mathematics, Hubei Normal university, Huangshi 43.002. China 2. Department of Automatic Control Engineering South China university of {2. Guangzhou 510641

We generalize and unify some recent results about extinction in nonautonomous n \|species competitive Lotka\|Volterra system. We exhibit new algebraic criteria which guarantee that any solution with strictly initial values that is positive has the property that some of its components vanishes while other approaches a certain solution of their isolate subsystem.

关键词： lotka\|volterra system asymptotic behaviors extinction coexistence

Effect of two human growth hormone receptor antagonists on glomerulosclerosis in streptozotocin-induced diabetic rats

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Acta Pharmacologica Sinica 2004年第4期25卷 92-97页

作者： Wei LI, Li-hua ZHU, En-bi WANG, Zeng-can YE, Jun LIN, Li-he GUO1, Fei-hong LUO2. Xi-hong LIU2. Xin FANG2. Shui-xian SHEN2.institute of Biochemistry and Cell Biology, Shanghai institutes for Biological {2., Chinese Academy of {2.s, 2.hildren’s Hospital ofShanghaiMedical university, Shanghai2.003., China institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Science Chinese Academy of Sciences Children\'s Hospital of Shanghai Medical University Shanghai 200031 China

AIM: To explore the feasibility of human growth hormone (hGH) receptor antagonist in the treatment of end-stage diabetic renal complications. METHODS: Two hGH mutants, hGHA1 (Cys-hGH-del1-4, G12.R, K168A, E174A, C182., del186-191) and hGHA2.(hGH-H2.A, G12.R, E174A) were expressed in E coli. The IC50 (Mean±SD) values for the mutants for inhibiting 12.I-hGH binding to rabbit growth hormone receptor were (65±10) ng for hGHA1, (2.±5.6) ng for hGHA2. and (10±0.6) ng for wild type hGH, respectively. RESULTS: After treatment for 12.weeks, the renal histology analysis showed that treatment with hGHA2.at 4 mg/kg body weight daily markedly suppressed glomerulosclerosis in streptozotocin-induced diabetic Sprague-Dawley (SD) rats; hGHA1 at the same dosage slightly increased the renal damage compared with saline; while wild type hGH at 1 U/kg body weight daily severely worsened the glomerulo-sclerosis in diabetic SD rats. CONCLUSION: The data indicated that hGHA2.inhibited the end-stage glomerulosclerosis in diabetic rats, but hGHA1 mildly increased the glomerulosclerosis.

关键词： growth hormone diabetic nephropathies mutation diabetes mellitus

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垃圾衍生燃料等温快速热解和燃烧反应特性

燃料化学学报 2004年第4期32卷 440-445页

作者：王志奇陈勇青岛科技大学化学与分子工程学院山东青岛266042 中国科学院广州能源研究所广东广州510070

利用热天平和管式炉对RDF(RefuseDerivedFuel)等温快速热解和燃烧反应特性进行了研究。实验发现,在等温快速升温的条件下,RDF热解和燃烧的反应速率都非常快,从受热开始到反应结束需60s～80s;从开始失重到完成反应为2.s。RDF热解和燃烧... 详细信息

利用热天平和管式炉对RDF(RefuseDerivedFuel)等温快速热解和燃烧反应特性进行了研究。实验发现,在等温快速升温的条件下,RDF热解和燃烧的反应速率都非常快,从受热开始到反应结束需60s～80s;从开始失重到完成反应为2.s。RDF热解和燃烧热重反应曲线非常类似,都只有一个反应失重区;RDF组成对其燃烧和热解反应性有重要影响,含有橡胶的RDF的热解和燃烧反应速率较小。在650℃～800℃RDF快速热解产物中气、液产物的产率可达80%～90%,而固体产物的产率只有10%～2.%,热解气体的热值为2.kJ/m3.RDF较适合进行热解处理。

关键词：垃圾衍生燃料等温快速热解等温快速燃烧热解产物

EXISTENCE OF INFINITELY MANY SOLUTIONS FOR ELLIPTIC PROBLEMS WITH CRITICAL EXPONENT

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Acta Mathematica Scientia 2004年第3期24卷 395-402页

作者：傅红卓沈尧天 Department of Mathematics South China University of Technology Guangzhou 510640 China Department of Mathematics University of Science and Technology of China Hefei 230026 China Department of Mathematics South China University of Technology Guangzhou 510640 Chinahis paper is concerned with the following nonlinear Dirichlet problem:where △pu = div(| ▽u|p- 2 ▽u) is the p-Laplacian of u Ωis a bounded domain in Rn (n > 3) 1 < p < n p = -pn/n-p is the critical exponent for the Sobolev imbedding λ> 0 and f(x u) satisfies some conditions. It reaches the conclusion that this problem has infinitely many solutions. Some results as p = 2 or f(xu) = |u|q-2u where 1 < q < p are generalized.

This paper is concerned with the following nonlinear Dirichlet problem:where △pu = div(| ▽u|p- 2.▽u) is the p-Laplacian of u, Ω is a bounded domain in Rn (n > 3., 1 0 and f(x, u) satisfies some conditions. It reaches the conclusion that this problem has infinitely many solutions. Some results as p = 2.or f(x,u) = |u|q-2., where 1 < q < p, are generalized.

关键词： critical Sobolev exponent concentration compactness principle genus infinitely many solutions

Synthesis and Enhanced Superplasticity of the Zirconia-dispersed Alumina Nanocomposite

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Journal of Materials science & technology 2005年第1期21卷 79-82页

作者： Guoqing CHEN, Kaifeng ZHANG, Wenbo HAN and Junting LUOSchool of Materials science and Engineering, Harbin institute of {2., Harbin 150001, ChinaProf., Ph.D., Sch. of Mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

A series of alumina-zirconia composites with various grain sizes were prepared from the nano-sized powders with different agglomerations. Microstructural analysis of the sintered compacts indicates that the as-sintered material is a typical intra/inter granular nanocomposite with uniform distribution of the zirconia grains in the alumina matrix. Superplastic deep drawing test under different conditions demonstrates that dense Al2.3.ZrO2.samples with average grain size of 2.1} nm can be elongated to a dome height of at least 12.mm at the punch rate of 0.6 mm·min-1 at 1400℃. Further drawing tests show that for the composites with larger grain size, such elongation cannot be achieved at such a strain rate.

关键词： Nanocomposite Synthesis Microstructure Superplasticity