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931.
We theoretically and experimentally demonstrate that refractive index of the prism used to load metal film has significant
influence on sensitivity of surface plasmon resonance based sensors. The prism with lower refractive index gives the sensors
a higher sensitivity in detecting refractive index variations of a sample. We attribute this effect to the fact that a prism
with low refractive index will increase coupling distance between surface plasmons and the medium under investigation.
Foundation item: Supported by Wuhan University and National Education Ministry of China
Biography: Wang Guo-ping (1964-), male, Professor, research direction: bolographic materials, diffractive optical elements,
optical properties of metallic nanopracticles and metal-dielectric nanostructures 相似文献
932.
A semantic retrieval method based on the fuzzy reasoning 总被引:1,自引:0,他引:1
This paper gives a semantic fuzzy retrieval method of multimedia object, discusses the principle of fuzzy semantic retrieval
technique, presents a fuzzy reasoning mechanism based on the knowledge base, and designs the relevant reasoning algorithms.
Researchful results have innovative significance.
Foundation item: Supported by the Natural Science Foundation of Hubei Province(No. 200J157)
Biography: Cao Jia-heng(1946-), male, Professor, research direction: multimedia software, artificial intelligence. 相似文献
933.
Model of production planning and scheduling in shop floor based on collaboration and competition 总被引:1,自引:0,他引:1
The planning and scheduling in real shop floor is actually achieved by coordination between different persons. In this process,
cooperation is mainstream, but competition also exists, for example, the competition between different groups, operators with
the same skill, etc. In multi-agent based shop floor management and control system, this competition and cooperation relation
must be embodied. The general process of shop floor production planning and scheduling is studied, and a colored Petri-net
model for the competition and cooperation process of three main agents in such system to achieve shop floor production planning
and scheduling is presented. The evaluating method of bids in bidding process that especially embodies the competition relationship
is also presented. This colored Petri-net model gives a clear illustration of this complex coordination process to system
designers, effectively promotes the cooperative development.
Foundation item: Supported partly by the Hi-tech Program of China (China 863) (No. 863-511-943-009) and the National Natural
Science Foundation of China(No. 59990470)
Biography: Liu Shi-ping(1971-), male, Ph. D. candidate, research direaction: CIMS, intelligent manufacturing. 相似文献
934.
We develop an interconnect crosstalk estimation model on the assumption of linearity for CMOS device. First, we analyze the terminal response of RC model on the worst condition from the S field to the time domain. The exact 3 order coefficients in S field are obtained due to the interconnect tree model. Based on this, a crosstalk peak estimation formula is presented. Unlike other crosstalk equations in the literature, this formula is only used coupled capacitance and grand capacitance as parameter. Experimental results show that, compared with the SPICE results, the estimation formulae are simple and accurate. So the model is expected to be used in such fields as layout-driven logic and high level synthesis, performance-driven floorplanning and interconnect planning. 相似文献
935.
F Kemper C J?ger L B F M Waters Th Henning F J Molster M J Barlow T Lim A de Koter 《Nature》2002,415(6869):295-297
Carbonates on large Solar System bodies like Earth and Mars (the latter represented by the meteorite ALH84001) form through the weathering of silicates in a watery (CO3)2- solution. The presence of carbonates in interplanetary dust particles and asteroids (again, represented by meteorites) is not completely understood, but has been attributed to aqueous alteration on a large parent body, which was subsequently shattered into smaller pieces. Despite efforts, the presence of carbonates outside the Solar System has hitherto not been established. Here we report the discovery of the carbonates calcite and dolomite in the dust shells of evolved stars, where the conditions are too primitive for the formation of large parent bodies with liquid water. These carbonates, therefore, are not formed by aqueous alteration, but perhaps through processes on the surfaces of dust or ice grains or gas phase condensation. The presence of carbonates which did not form by aqueous alteration suggests that some of the carbonates found in Solar System bodies no longer provide direct evidence that liquid water was present on large parent bodies early in the history of the Solar System. 相似文献
936.
以日本《铁路费用效益分析手册 (99版 )》和中国《铁路建设项目经济评价办法 (第 2版 )》为参照 ,通过对比分析中日铁路项目国民经济评价方法的差异 ,提出日本铁路费用效益分析方法中的可借鉴之处 :借鉴日本评价方法分 3类界定受益群体的思路 ,解决我国现行方法存在的效益重复计算问题 ;以福利经济学和“有无对比法”作为项目评价的基本指导原则 ,解决我国由于评价原则模糊导致的同一项目不同评价结论的问题等 相似文献
937.
Qi QY Wang F Zhang HT Wang JC Xiao HP Wang MH Han YF Zhang RM Tao SH Luo ZW 《Cellular and molecular life sciences : CMLS》2003,60(11):2492-2500
CC chemokine receptor 5 (CCR5) is a member of the G-protein-coupled receptor superfamily. It plays an important role in macrophage tropic human immunodeficiency virus-1 entry and in some inflammatory reactions. CCR5-893(–) is a single-nucleotide deletion that results in complete truncation of the C tail of the gene product. We detected CCR5-893(–) in a sample of patients infected with non-tuberculosis mycobacteria and found that it was maintained heterozygously with a frequency of 2%. There is no association between this mutation and any immunodeficiency. Membrane expression of CCR5-893(–) was substantially reduced compared to the wild type, but this defective surface presentation recovered greatly recovered in the presence of 2 mg l-1 phytohemagglutinin (PHA). However, PHA inducement did not affect the total intracellular expression of CCR5-893(–) or wild-type CCR5. Thus we suggest there exist some PHA-induced factor(s) that could mediate the presentation of truncated CCR5.Received 23 July 2003; accepted 18 August 2003 相似文献
938.
高校图书馆“学科馆员”的角色定位 总被引:6,自引:0,他引:6
张晓敏 《科技情报开发与经济》2003,13(6):24-25
阐述了现代信息社会高校图书馆建立“学科馆员”制度的必然性,从学历水平、能力水平等方面探讨了“学科馆员”的角色定位与工作职责定位。 相似文献
939.
Li De |jia Li Hai |cheng Zou Guo |lin College of Life Sciences Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2003,8(3):875-879
0 IntroductionHemoglobin(Hb)isthemajorhemeproteinofredbloodcells(RBCs)andisresponsibleforthetransportofoxygentothetissues.ThefunctionofHbdependsupontheabilityoffer rousironinthehemegrouptobindandreleaseoxygen .Despiteitsprincipalroleasanoxygen carrier,theHbmoleculepossessesdifferentenzymaticactivities[1 ] andamethodwasdevelopedforthedeterminationofHbbasedonitsenzymaticactivityfortheox idationofo phenylenediamine (OPDA)withH2 O2 asanoxi dant[2 ] .Hbasamimeticenzymeofperoxidase ,cancataly… 相似文献
940.
Wang Li-na Fei Ru-chun Liu Zhu . State Key Laboratory of Software Engineering Wuhan University Wuhan Hubei China . Department of Information Engneering Benxi College of Metallurgy Benxi Liaoning China . School of Information Science Engineering Northeastern University Shenyang Liaoning China 《武汉大学学报:自然科学英文版》2003,8(4):1065-1069
0 IntroductionAblockcipherwithoutdataextensionorexpressionisaper mutation .Thesecurityofablockcipherschemeiscorrela tivewiththe permutations.Quicktrickle permutation[1 ] canmakethedatadisorderedwhenactingatthedataandmakeallprobabledistancebetweentwoelementsappear,soithasgoodcryptographicpropertiesandcanbeusedintheblockcipherwhichrequireshighsecurity.Aprivatekeyblockcipherisapermutationinn dimensionvectorspaceoverF2 atthecontrolofakey[2 ,3] .Moreover,manyblockciphersusepermutationstoexecuteso… 相似文献