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1.
曹悦 《科技信息》2009,(13):186-186
This article analyzes the kind of English we should teach in school under the world globalization, whether we should teach the Standard English or non-standard English. Finally, generate the discussion between teaching standard and non-standard variety of English not only in China but also other ESL and EOL countries.  相似文献   

2.
We show that the phase velocity in a stationary state of a de Broglie wave can be directly obtained from the probability distribution, i.e. the quantum trajectories, without detailed knowledge of the phase term itself. In other words, the amplitude of a de Broglie wave function describes not only the probability distribution but also the phase velocity distribution. Using this relationship, we comment on two calculations of the Goos-H nchen shift in de Broglie waves.  相似文献   

3.
In this paper, we improve the trawling and point out some communities missed by trawling. We use the DBG (Dense Bipartite Graph) to identify a structure of a potential community instead of CBG (Complete Bipartite Graph). Based on DBG, we proposed a new method based on edge removal to extract cores from a web graph. Moreover, we improve the crawler to save only potential pages as fans of a core and save a lot of disk storage space. To evaluate the set of cores whether or not belong to a community, the statistics of term frequency is used. In the paper, the dataset of experiment were crawled under domain ".cn". The result show that the our algorithm works properly and some new cores can be found by our method.  相似文献   

4.
Modal logics are good candidates for a formal theory of agents. The efficiency of reasoning method in modal logics is very important, because it determines whether or not the reasoning method can be widely used in systems based on agent. In this paper, we modify the extension rule theorem proving method we presented before, and then apply it to P-logic that is translated from modal logic by functional transformation. At last, we give the proof of its soundness and completeness.  相似文献   

5.
Asymptotical stability is an important property of the associative memory neural networks.In this comment,we demonstrate that the asymptotical stability analyses of the MV ECAM and MV-eBAM in the asynchronous update mode by Wang et al are not rigorous,and then we modify the errors and further prove that the two models are all asymptotically stable in both synchronous and asynchronous update modes.  相似文献   

6.
This thesis draws attention to one of the most vigorous debate in sociolinguistics,sexism in discourse,despite the chicken-and egg question whether it is our language shape sexism or sexism creates certain language.Unlike most researches conducted in sexism and language in the past,we challenge the traditional notion of linguistic sexism and direct our view to what we call "an indirect sexism" here.We then argue the difference between direct and indirect sexism and depict how such an undercurrent drives secretly and carefully in our daily discourse.  相似文献   

7.
We study the stationary and propagating solutions for a Bose-Einstein condensate (BEC) in a periodic optical potential with an additional confining optical or magnetic potential. Using an effective mass approximation we express the condensate wave function in terms of slowly-varying envelopes modulating the Bloch modes of the optical lattice. In the limit of a weak nonlinearity, we derive a nonlinear Schrodinger equation for propagation of the envelope function which does not contain the rapid oscillation of the lattice. We then consider the ground state solutions in detail in the regime of weak, moderate and strong nonlinear interactions. We describe the form of solution which is appropriate in each regime, and place careful limits on the validity of each type of solution. Finally we extend the study to the propagating dynamics of a spinor atomic BEC in an optical lattice and some interesting phenomena are revealed.  相似文献   

8.
In this paper, we analyze two signcryption schemes on elliptic curves proposed by Zheng Yu liang and Hideki lmai. We point out a serious problem with the schemes that the elliptic curve based signcryption schemes lose confidentiality to gain non repudiation. We also propose two improvement versions that not only overcome the security leak inherenl in the schemes but also provide public verifiability or forward security. Our improvement versions require smaller computing cost than that required by signature-thenencryption methods.  相似文献   

9.
In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders' equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage.  相似文献   

10.
We consider the problem of packing d-dimensional cubes into the minimum number of 2-space bounded unit cubes. Given a sequence of items, each of which is a d-dimensional.d 3/ hypercube with side length not greater than 1 and an infinite number of d-dimensional.d 3/ hypercube bins with unit length on each side, we want to pack all of the items in the sequence into the minimum number of bins. The constraint is that only two bins are active at anytime during the packing process. Each item should be orthogonally packed without overlapping other items. Items are given in an online manner without the knowledge of or information about the subsequent items. We extend the technique of brick partitioning for square packing and obtain two results: a three-dimensional box and d-dimensional hyperbox partitioning schemes for cube and hypercube packing, respectively. We design5.43-competitive and 32/21 2d-competitive algorithms for cube and hypercube packing, respectively. To the best of our knowledge these are the first known results on 2-space bounded cube and hypercube packing.  相似文献   

11.
We studied the information search behaviors of Chinese consumers of miniature automobiles. First, we identified the main sources where consumers acquire or seek information about miniature automobiles and discussed their extent of information search. Then, based on logistic regression and optimal scaling regression of statistics, we studied the influences of characteristics of consumers of miniature automobiles on the extent of information search and on Internet usage. The results indicate that consumers often utilize four sources to obtain information about miniature automobiles. The dominant information source for consumers is their friends/family, followed by dealers, newspapers, and TV. Age, occupation, education and income significantly affect the extent of information search, but gender and city of residence do not have significant impacts. Age, city of residence, occupation, education and income produce significant influences on Internet usage. Gender has an insignificant influence on whether a consumer uses the Internet to search for information.  相似文献   

12.
This paper mainly discusses the multiscale computation from a chemical engineering perspective. From the application designer' s perspective, we propose a new approach to investigate and develop both flexible and efficient computer architectures. Based on the requirements of applications within one category, we first induce and extract some inherent computing patterns or core computing kernels from the applications. Some computing models and innovative computing architectures will then be developed for these patterns or kernels, as well as the software mapping techniques. Finally those applications which can share and utilize those computing patterns or kernels can be executed very efficiently on those novel computing architectures. We think that the proposed approach may not be achievable within the existing technology. However, we believe that it will be available in the near future. Hence, we will describe this approach from the following four aspects: multiscale environment in the world, mesoscale as a key scale, energy minimization multiscale (EMMS) paradigm and our perspective.  相似文献   

13.
Xu  LiZhong  Zhu  Yu  Zhang  JiangShan  Xiao  LiangJian 《科学通报(英文版)》2009,54(24):4679-4687
This is a report on payment card format contingent valuation prediction validity in China based on the individual level comparison in a world heritage site evaluation. An evaluation index system of indicators is set up according to the consistency of the individual willingness to pay as well as the mean (or median), the positive (or negative) proportion in the hypothetical context and those in the actual donation context. We took the conservation of a combined world heritage site Wuyi Mountain in China as the case study. By one-to-one individual level comparison, we demonstrate that people usually overstate their paying intention and overestimate their paying abilities, and the hypothetical individual WTP, mean, median, positive proportion and negative proportion are all significantly different from those in the actual context in this case. However, although the relationship between WTP and socioeconomic characteristics in the hypothetical context was not consistent with that in the actual situation, the survey still demonstrated the maximum support proportion and the least opponent proportion to the project when it was carried out. So we can conclude that in this case PC format CV is a poor indicator, partly owning to its free binding. We also find that when a person decides whether to pay (intention), he or she is more affected by his/her knowledge structure and social duty; when he/she really decides on how much he/she will pay, income becomes the most important factor.  相似文献   

14.
This paper describes the development of a knowledge-based system (KBS) for determining whether or not, and under what conditions, a bank loan officer should grant a business loan to a company. The prototype system developed focuses on what is bank loans risks management, how to prevent risk by the analysis of the ability of paying back loans. The paper makes the structural analysis involved in the system's decision situation, the structured situation diagram or model, dependency diagram and the document needed by the KBS prototype system thus are developed. Through testing the samples from loan business, the quality for the analysis of the ability of paying back loans can be effectively evaluated by the KBS prototype system.  相似文献   

15.
Two major classes of plant sugar transporters, sucrose and monosaccharide transporters, may be localized to tonoplast or plasma membrane. The monosaccharide transporters may also be localized in plastid. However, whether these transporters reside in other subcellular compartments remains unclear. We recently detected in apple fruit a 52 kD plasma membrane-localized monosaccharide transporter, and showed that this transporter may be functional in phloem unloading in the fruit. In this paper, we report that this monosaccharide transporter is also localized to sieve plate and plasmodesmal channel in apple fruit. The amount of this sieve plate- and plasmodesma-associated transporter changes during fruit development. This amount of the transporter expression may be altered in the phloem sieve elements but not in the parenchyma cells by a photoassimilate deficiency applied by the shoot girdling treatment, suggesting that the monosaccharide transporter of the special sub-cellular localization may be of biological significance.  相似文献   

16.
陈思雨 《科技信息》2012,(22):168-169
The following essay will discuss the topic"Is Hosting an Olympics a Fortune to the City or a Disaster to the City,Why?"First of all,it should be clarified that we focus on the relationships between an Olympics and the city which hosts it,not the country which governs the city.Secondly,since different cities have different political,financial,social,and cultural backgrounds,it appears to be not easy for us to analyze this issue in a broad way.Consequently,this essay concentrates on the 2008 Olympic Games and its impacts on Beijing.By discussing the three concepts of Olympic Games,people’s participation and the economic development,we can see that the 29th Olympics Games made more contributions to Beijing.  相似文献   

17.
Based on Bayes‘ theorem we point out that the false positive rate must be lower than the intrusion base rate in order to make the Alarm Credibility Probability of the intrusion detection system exceed 50%. We present the methods that have been used in our developing intrusion detection system AIIDS (artificial immune intrusion detection systems) to increase the creditability of anomaly detection system. These methods include increasing the regularities of the system call trace by use of Hidden Markov Model (HMM), making every antibody or detector has finite lifetime, offering the detector a co-stimulate signal to illustrate whether there is damage in the system according to the integrity, confidentiality, or availability of the system resource.  相似文献   

18.
How to define the value of the Right in Additional Al location of Stocks (RAAS) acts an important role in stock markets whether or not the shareholders execute the right. Moreover, the valuation defining of RAAS an d the exercise price (K) are mutual cause and effect. Based on some literatures on this subject, this paper presents a model valuing the RAAS per-share. With t he opening information in ShenZheng Stock Markets, we make a simulation on the R AAS‘s value of shenwuye, which is a shareholding corp...  相似文献   

19.
Exactly hoxv we learn our own or a secondl~age is still not colllpletely again,but we do knowin general terms What is involved in the process Oflanguage learning .As English teachers,we cann'teasily evaluate teaching methods without some idea ofhow We could then sac that we have 'lend' a smallstudents learn.In this essay we shall look briefly atthree defferent kinds of learning,and consider theirimPOhance in learning Englishtleaming by heart,forming habits,and acquiring rules.Learning by he…  相似文献   

20.
Whether life vestige existed in Martian meteorites or not has provoked a hot tide toward Mars exploration. Among the other things, whether water existed in Marsor not again becomes a hot point of contemporary sci- entific exploration. Analyzing the hydrog…  相似文献   

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