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1.
朱书阳 《科技信息》2009,(6):122-123
Introduction
SMES are generally considered to be flexible to adapt to e-commerce. They are considered to be a major component of all economies and are generally considered to be flexible, adaptive and innovative organizations (Rao et al, 2003). E-commerce is introduced to SMES and has a rapid growth of adoption. The open structure and low cost of using Internet provide a chance to communicate and collecting information conveniently to buyers and sellers.  相似文献   

2.
Quantum information processing and communication(QIPC) is an area of science that has two main goals: On one side,it tries to explore(still not well known) potential of quantum phenomena for(efficient and reliable) information processing and(efficient,reliable and secure) communication.On the other side,it tries to use quantum information storing,processing and transmitting paradigms,principles,laws,limitations,concepts,models and tools to get deeper insights into the phenomena of quantum world and to find efficient ways to describe and handle/simulate various complex physical phenomena.In order to do that QIPC has to use concepts,models,theories,methods and tools of both physics and informatics.The main role of physics at that is to discover primitive physical phenomena that can be used to design and maintain complex and reliable information storing,processing and transmitting systems.The main role of informatics is,one one side,to explore,from the information processing and communication point of view,limitations and potentials of the potential quantum information processing and communication technology,and to prepare information processing methods that could utilise potential of quantum information processing and communication technologies.On the other side,the main role of informatics is to guide and support,by theoretical tools and outcomes,physics oriented research in QIPC.The paper is to describe and analyse a variety of ways and potential informatics contributes and should/could contribute to the development of QIPC--see also Gruska(1999,2006,2008).  相似文献   

3.
After half a century of focussed hard work, the University of Science and Technology of China (USTC) recently celebrated the 50th anniversary of its founding. President Hu Jingtao sent a con- gratulatory letter, encouraging USTC to strengthen its sense of mission and responsibility, to aim for cutting edge scientific and technological research, to serve China's strategic development needs, to creatively teach and research and to do all possible to build a world-class research university.  相似文献   

4.
陈月仙 《科技信息》2009,(14):122-124
With international trades become more and more popular, cultural conflicts and shocks appeared in our life more and more frequently. We have to begin to pay attention to the differences of a lot of aspects and professions in different cultures. Because agriculture and farmer are the basis of every country, it is necessary to compare them in different culture and different nations. Except being industrious, hardy and brave, what differences there are between them? And how to treat these differences correctly are becoming especially serious and necessary.  相似文献   

5.
The relationships and the features of integration between Enterprise Process Monitoring and Controlling System (EPMCS) and Enterprise Process Related Applications (EPRA) were analyzed. An integration architecture centered on EPMCS was presented, in which there were four layers to conneet from EPMCS to EPRA: EPMCS, application integration layer, transport layer and EPRA, and there were four layers used to etstablish integration: presentation layer, function layer, data layer and system layer. The frameworks to connect EPMCS and EPRA were designed, that Enterprise-Independent Model (ELM), Enterprise-Specific Model (ESM) and metamodel to describe these two models were defined. The method to integrate data based on XML was designed to exchange data from EPMCS to EPRA according to the mapping between EIM and ESM. The approches are suitable for integrating EPMCS and systems in Product Data Management (PDM), project management and enterprise business management.  相似文献   

6.
Two tree ring-width chronologies of Sabina tibetica were developed based on cores sampled in Qumalal and Zhiduo, southern Qinghai Plateau. The response function analysis showed that the chronologies were sensitive to temperature and precipitation from April to June in the plateau. Moisture index (MI) was defined, reconstructed and extended back to AD 1550. The cross-validation method was used to check the stability of the calibration equation, and the result indicated that the equation was stable. Six severe dry periods were found in this region in the past 453-year reconstruction, which were 1592 to 1610, 1649 to 1665, 1687 to 1697, 1740 to 1750, 1818 to 1829 and 1918 to 1933. Five severe wetting periods were 1669 to 1682, 1700 to 1709, 1800 to 1814, 1898 to 1909 and 1935 to 1950. Spectrum analysis indicated that there existed long-term cycles of 60.4 and 53.4 a, solar cycle of 11 a and short-term cycles of 8, 6 and 4 a in the reconstructed series.  相似文献   

7.
Lianas are a principal physiognomic component of tropical and subtropical forests and are typically considered to be parasites of trees. In contrast, the substantial contribution of lianas to rainforest leaf litter production (up to 40%) suggests that they play important roles in nutrient cycles and may benefit their host trees. Lianas contribute disproportionately to total forest litter production at least partially because lianas invest relatively little in support structures and proportionately much more to leaf production when compared with trees. In contrast to tree leaves, liana leaves are higher in nutrient concentrations, relatively short-lived, and decompose more rapidly. In addition, the special life form of lianas allows them to grow vertically and horizontally in the forest and relocate nutrients, mainly towards their host trees, through the production of leaf litter. Consequently, lianas may contribute substantially to the high rainforest productivity, and the roles they play in liana/tree associations and rainforest dynamics needs to be re-evaluated.  相似文献   

8.
Rootkits, which unnoticeably reside in your computer, stealthily carry on remote control and software eavesdropping, are a great threat to network and computer security. It's time to acquaint ourselves with their implement and detection. This article pays more attention to kernel rootkits, because they are more difficult to compose and to be identified than useland rootkits. The latest technologies used to write and detect kernel rootkits, along with their advantages and disadvantages.  相似文献   

9.
Entransy, a recently developed concept, is the central physical quantity characterizing heat transfer processes not related to heat-to-work conversions. The entransy of an object pertains to the nature of the potential energy of heat in a thermal field and describes its heat transfer ability. In the present study, we revisit this concept, and develop its relationship to state and process quantities. This then enables a direct comparison to the more familiar concept, entropy, the central physical quantity in thermody- namics. The comparison helps to identify the role entransy has in heat transfer processes and highlight under what conditions state and process quantities related to entransy can be distinguished in such processes. As to embody the entransy loss due to work expended between the system and its environment for the irreversible heat conduction in gases, new quantities, available entransy flow and available system entransy are introduced. Both the entransy of solids and the available system entransy of gases are state quantities and their changes correspond to the entransy flow and the available entransy flow respectively. Thus there is no need to stress the difference between process quantity and state quantity in heat transfer.  相似文献   

10.
In this paper,by utilizing the angle of arrivals (AOAs) and imprecise positions of the sensors,a novel modified Levenberg-Marquardt algorithm to solve the source localization problem is proposed.Conventional source localization algorithms,like Gauss-Newton algorithm and Conjugate gradient algorithm are subjected to the problems of local minima and good initial guess.This paper presents a new optimization technique to find the descent directions to avoid divergence,and a trust region method is introduced to accelerate the convergence rate.Compared with conventional methods,the new algorithm offers increased stability and is more robust,allowing for stronger non-linearity and wider convergence field to be identified.Simulation results demonstrate that the proposed algorithm improves the typical methods in both speed and robustness,and is able to avoid local minima.  相似文献   

11.
The term "neurodevelopmental disorder" broadly encompasses conditions thought to arise early in development and includes schizophrenia, bipolar disorder and autism among others. These conditions share a number of genetic and environmental risk factors postulated to lead to common difficulties in socio-emotional processing, communication and cognitive function. The alternative position is that, while the same traits are affected across these conditions, the nature or direction in which they are modified may be distinct. MRI studies provide a rapidly expanding and rich database which we propose can be used to contribute to this debate. Anatomical likelihood estimation (ALE) is a method of meta-analysis applied to voxel-based MRI studies. We have adapted this method to explore the extent to which schizophrenia and bipolar disorder and schizophrenia and autism share a common brain structural phenotype. We will review this work here and discuss whether there is sufficient other evidence to justify a common framework for further research into the inter-relatedness of such conditions.  相似文献   

12.
The Major Research Program "Deep Sea Processes and Evolution of the South China Sea", or "The South China Sea Deep", launched in January 2011 by the National Natural Science Foundation of China, is the first large-scale basic-research program in ocean science in the country aiming to reconstruct the life history of a marginal sea. The overall scientific objective of the program is to dissect this typical marginal sea by studying its history of evolution and its modern processes, including the following three major components:(1) Development of the deep basin:utilizing new techniques to re-measure magnetic anomaly lineations, to explore the deep tectonic features, to drill the oceanic crust, and to study volcanic seamount chains; (2) deep-water sediments: observing the modern processes to reveal the patterns of deep-water circulations and sedimentation, analyzing deep-sea sediments to recognize paleoceanographic response to basin evolution, and subsequently to bridge the modern and paleo-studies of the deep-sea processes; and (3) biogeochemical processes:using a variety of techniques including deploying submarine observation and deep-water diving device to investigate the distribution patterns and environmental impacts of deepwater seepages and sub-bottom circulation, and to reveal the role of microbes in deep-sea carbon cycling. As compared with the open ocean and other marginal seas, the South China Sea enjoys many more advantages as a marine basin for reconstructing the life history. Meanwhile, the South China Sea Deep Program provides unique opportunities in studying the evolution and variations of the sea-land interactions between the Pacific and Asia.  相似文献   

13.
正博士后[德国]University of Munich University of Munich,Germany opens postdoctoral fellow positionsin Neuroscience.The research focuses on molecular and cellular mechanisms leading to chronic neurological problems(e.g.dementia,epilepsy and psychiatric disorders).You are:curious about basic science and carry a great interest in exploring how thebrain functions;always looking for solutions to turn great ideasand opportunities to actions;always willing to learn,and have thecourage to ask questions when you don’t know;open to expressyour opinions and receive feedbacks/critics;a team player and  相似文献   

14.
This text goes deep in to analyze the asphalt road to face to produce the whole reason of gravamen,and put forward and should adopt of correspond the counterplan and measures.  相似文献   

15.
Facing the increasing security issues in P2P networks, a scheme for resource sharing using trusted computing technologies is proposed in this paper. We advance a RS-UCON model with decision continuity and attribute mutability to control the usage process and an architecture to illustrate how TC technologies support policy enforcement with bidirectional attestation. The properties required for attestation should include not only integrity measurement value of platform and related application, but also reputation of users and access history, in order to avoid the limitation of the existing approaches. To make a permission, it is required to evaluate both the authorization and conditions of the subject and the object in resource usage to ensure trustable resources to be transferred to trusted users and platform.  相似文献   

16.
Using the definition of vulnerability provided by the Intergovernmental Panel on Climate Change,this paper assesses the vulnerability of areas affected by Chinese cryospheric changes from 2001 to 2020 and from 2001 to 2050 in A1 and B1scenarios.Seven indices are used in the vulnerability assessment:glacial area fraction,interannual variability of permafrost depth,interannual variability of surface snow area fraction,interannual variability of surface runoff,interannual variability of surface temperature,interannual variability of vegetation growth,and interannual variability of the human development index.Assessment results show that the overall vulnerability of the studied areas in China increases from east to west.The areas in the middle and eastern parts of China are less vulnerable compared with western parts and parts of the Tibetan Plateau.The highest vulnerability values are found from 1981 to 2000,and the least ones are found from 2001 to 2050.The vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2050,and the less vulnerable areas decrease.The highly vulnerable areas increase from the period of 1981 to 2000 to the period of 2001 to 2020 and then decrease from the period of 2001 to 2020 to the period of 2001 to 2050.This decrease in vulnerability is attributed to the decrease in exposure and sensitivity to Chinese cryospheric changes along with a concomitant increase in adaptation.  相似文献   

17.
周成 《科技信息》2009,(31):I0201-I0201
Many students don't know how to learn English at college. Without a goal in life and unable to manage their time, they are likely to idle away their youth. This paper intends to offer some suggestions to students on how to learn English at college, and hopefully they will experience the satisfaction and pleasure of learning English.  相似文献   

18.
According to the political system of our country, the administrative power operation has a strong tendency of expansion and arbitrariness, squeezing the citizens private right . How to supervise the expansion and arbitrariness of administrative power? How to operate administrative power well? The news public opinion would be the valid mechanism to supervise administrative power operation. Involving a practical case. This article starts with the valid function and encountered problem meeting of news public supervision, elaborates the reason and legal principle of the supervision news public opinion to administrative power operation, reviews and comments actualities and prob- lems of the news pubic supervision in our country, explores valid mechanism about supervision of news public opinion to administrative power operation, then tries to put forward some measures to improve and enhance our news public supervision.  相似文献   

19.
Biosorption and biodegradation of phenanthrene and pyrene by live and heat-killed Phanerochaete chrysosporium are investigated to elucidate the bio-dissipation mechanisms of polycyclic aromatic hydrocarbons(PAHs) in aqueous solution and its regulating factors.The effects of nutrient conditions(carbon source and nitrogen source concentrations),the co-existing Cu 2+,and repeated-batch feed of PAHs on the biosorption and biodegradation are systematically studied.The removal of PAHs by dead bodies of P.chrysosporium is attributed to biosorption only,and the respective partition coefficients of phenanthrene and pyrene are 4040 and 17500 L/kg.Both biosorption and biodegradation contribute to the dissipation of PAHs by live P.chrysosporium in water.After a 3-d incubation,the removal percentage via biosorption are 19.71% and 52.21% for phenanthrene and pyrene,respectively.With the increase of the incubation time(3 40 d),biodegradation gradually increases from 20.40% to 60.62% for phenanthrene,and from 15.55% to 49.21% for pyrene.Correspondingly,the stored-PAHs in the fungal bodies decrease.Under the carbon-rich and nitrogen-limit nutrient conditions,the removal efficiency and biodegradation of phenanthrene and pyrene are significantly promoted,i.e.99.55% and 92.77% for phenanthrene,and 99.47% and 83.97% for pyrene after a 60-d incubation.This phenomenon is ascribed to enhanced-biosorption due to the increase of fungal biomass under carbon-rich condition,and to stimulated-biodegradation under nitrogen-limit condition.For the repeated-batch feed of phenanthrene,the pollutant is continuously removed by live P.chrysosporium,and the contribution of biodegradation is enhanced with the repeated cycles.After 3 cycles,the biodegradation percentage is up to 90% with each cycle of a 6-d incubation.  相似文献   

20.
尹冬伟  齐茜 《科技信息》2011,(3):I0190-I0190
1 IntroductionForeign language teaching generally refers to the theory and practice of teaching a foreign language.It has close connection with linguistics,psychology,education,philosophy,sociology and other disciplines.Since linguistics and foreign language teaching both study language phenomena on the aspects of theory and practice,the two are much closely related to each other.Linguistics is beneficial to language teaching in two aspects: Firstly,applied linguistics extends theoretical linguistics in the direction of language learning and teaching,so that the teacher is enabled to make better decisions on the goal and content of the teaching.Secondly,applied linguistics states the insights and implications that linguistic theories have on the language teaching methodology.Once the goal and content of the teaching are settled,the teacher has to consider questions of how to teach.As an English teacher it really enriches my mind on what to teach and how to teach more effectively.This paper will focus on Sapir-Whorf Hypothesis and its implications on second language teaching.  相似文献   

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