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611.
The security issues of mobile agent system have embarrassed its widespread implementation. The paper analyses communication security threats and countermeasures of mobile agent system and proposes a communication security protocol of mobile agent system. It provides multifactor authentication, encryption transmission, and integrity protection of mobile agent.  相似文献   
612.
<正> In this paper,an equivalency condition of nonsingularity in nonlinear semidefinite programming,which can be viewed as a generalization of the equivalency condition of nonsingularity for linearsemidefinite programming,is established under certain conditions of convexity.  相似文献   
613.
<正> A family of integral-type goodness-of-fit tests is investigated.This family includes someexisting tests,such as the Cramér-von Mises test and Anderson-Darling test,etc.The asymptoticdistributions of the tests in the family under the null and local alternative hypotheses are established.The almost sure convergence under a fixed underlying distribution is obtained.Furthermore,simulationsare conducted to compare the powers of the tests in the family.Simulation results show that fordifferent alternatives,the more powerful tests are different,and the parameter λ has great influence onthe tests in small sample cases.  相似文献   
614.
Soft Systems Methodology is especially useful in diagnosing and addressing organizational problems and designing new systems in cultures that are characterised by pluralistic views and values. This paper demonstrates how SSM workshops in a large government agency resulted in a high level of creativity. SSM is then proposed as a methodology that could enhance group creativity in organizational design contexts.  相似文献   
615.
Increasingly knowledge has become a determining factor in achieving life’s potential and is the currency of the age. Without access to Information an individuals’ knowledge base cannot be enriched and without knowledge the individual becomes increasingly powerless. Advances in technology have provided opportunities for some to add to their stock of knowledge but access to sources of information is uneven and can lead to social unrest. The availability of information is an important factor in managing change and empowering citizens. The question about information and power then becomes one of ownership or sovereignty of the information. If we are to create an open society then we need to ensure that there is open access to knowledge through flexible and intelligent information systems that are available for all. In this paper we consider if we are truly entering the knowledge age or the age of ignorance.  相似文献   
616.
Arabidopsis thaliana, a model plant species, has a number of advantages over other plant species as an experimental organism due to many of its genetic and genomic features. The Chinese Arabidopsis community has made significant contributions to plant biology research in recent years[1,2]. In 2006, studies of plant biology in China received more attention than ever before, especially those pertaining to Arabidopsis research. Here we briefly summarize recent advances in Arabidopsis re-search in China.  相似文献   
617.
This paper proposes a method to formalize the interoperation in multi-domain environment. Through employing the algebra method, we conclude four types of the conflicts for the interoperation, and analyzes the cause of the policy conflicts. For each type of conflicts, we formalize it and proposes the method of detection and resolution. Finally, the method is illuminated be effective through comparing our work with others.  相似文献   
618.
The composite membranes with cellulose acetate (CA) as the separating layer material and polyacrylonitrile (PAN) as the supporting layer material were prepared for separating caprolactam (CPL) from CPL/water mixtures by pervaporation technique. The swelling experiments were carried out to investigate the effects of swelling time and CPL concentration on the degree of swelling. The results showed that the CA membrane reached swelling equilibrium within 24 h, and the degree of swelling first slightly decreased then increased with the increase of CPL concentration in the feed under the experimental conditions. Respectively comparing flux with permeance, and separation factor with selectivity, we found out that the separation performance of the CA/PAN composite membrane is more strongly dependent on its hydrophilic/hydrophobic nature as well as on the effects of operating parameters, such as feed composition concentration and feed temperature.  相似文献   
619.
<正> This paper considers the problem of actuator failure compensation for a class of nonlinearsystems in the form of output-feedback.MT-filters are exploited to estimate the unmeasured states.The backsteppping technique is used to construct the controller recursively.The proposed compensationscheme can grantee the boundedness of all the closed-loop signals and asymptotic output tracking.Thetheoretical results are illustrated by a simulation example.  相似文献   
620.
Solidification of Fe-7.5%Mo-16.5%Si ternary quasiperitectic alloy is investigated by using differential scanning calorimetry (DSC) and drop tube containerless processing techniques.The primary phase is identified as R (Fe5Mo3Si2) and the quasiperitectic phases are τ1 (Fe5MoSi4) and Fe3Si.With the decrease of droplet diameter, the cooling rate and undercooling of the droplets in-crease rapidly.The experiment result indicates that the solidification microstructure is composed of remnant primary phase, qua-sip...  相似文献   
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