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1.
项目借款偿还方式的分析与确定 总被引:2,自引:0,他引:2
对项目借款的偿还方式进行了分析,讨论了如何确定一种适宜的偿还方式。熟练掌握项目借款偿还方式及其确定方法对参与项目建设的人员十分必要。 相似文献
2.
阐述了企业人力资源投资财务评价应解决的两个重要问题:评价对象的分类和项目的财务现金流量的内容。 相似文献
3.
Christos Bouras Agisilaos Konidaris 《International Journal of Communication Systems》2005,18(2):119-142
Redundant data transfers over the Web, can be mainly attributed to the repeated transfers of unchanged data. Web caches and Web proxies are some of the solutions that have been proposed, to deal with the issue of redundant data transfers. In this paper we focus on the efficient estimation and reduction of redundant data transfers over the Web. We first prove that a vast amount of redundant data is transferred in Web pages that are considered to carry fresh data. We show this by following an approach based on Web page fragmentation and manipulation. Web pages are broken down to fragments, based on specific criteria. We then deal with these fragments as independent constructors of the Web page and study their change patterns independently and in the context of the whole Web page. After the fragmentation process, we propose solutions for dealing with redundant data transfers. This paper has been based on our previous work on ‘Web Components’ but also on related work by other researchers. It utilises a proxy based, client/server architecture, and imposes changes to the algorithms executed on the Proxy server and on clients. We show that our proposed solution can considerably reduce the amount of redundant data transferred on the Web. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
4.
对2004年中国证券市场上的129家金属和非金属行业上市公司的会计账面盈利与现金流量的相关性进行实证研究后,发现两者的相关程度很低,很大一部分上市公司的账面盈利没有形成相应的现金流入,导致两者之间产生“滞脱”的效应.因此,笔者认为在对企业的财务状况进行评价时,不能仅仅局限于使用一些反映企业账面盈利的指标,应该还需要考虑一些反映企业创造现金流量能力的指标. 相似文献
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6.
Chun-I Fan 《Information Sciences》2006,176(3):263-284
In an untraceable electronic cash protocol based on blind signatures, an identified customer can withdraw a blinded electronic cash from the bank and the unblinding operation is adopted by the customer to transform the blinded electronic cash into a valid one. Before performing the operation, the blinded electronic cash is protected well since attackers cannot convert it into a valid electronic cash without the blinding factor corresponding to the operation. However, after unblinding, the electronic cash will suffer from the theft attacks since it is not protected by any security mechanism. This paper introduces a new unblinding operation called ownership-attached unblinding which attaches the identities of a designated payee and a specified transaction to the blinded electronic cash and then produces an ownership-attached electronic cash other than a bare one such that the cash can withstand the theft attacks during the entire transaction because it is valid for the designated payee and the specified transaction only. Furthermore, the proposed scheme does not largely increase the computation cost required for each customer so that it also is a customer efficient protection solution for untraceable electronic cash and especially suitable for mobile clients and smart-card users. 相似文献
7.
Fairly exchanging digital content is an everyday problem. It has been shown that fair exchange cannot be achieved without a trusted third party (called the Arbiter). Yet, even with a trusted party, it is still non-trivial to come up with an efficient solution, especially one that can be used in a p2p file sharing system with a high volume of data exchanged.We provide an efficient optimistic fair exchange mechanism for bartering digital files, where receiving a payment in return for a file (buying) is also considered fair. The exchange is optimistic, removing the need for the Arbiter’s involvement unless a dispute occurs. While the previous solutions employ costly cryptographic primitives for every file or block exchanged, our protocol employs them only once per peer, therefore achieving an O(n) efficiency improvement when n blocks are exchanged between two peers. Our protocol uses very efficient cryptography, making it perfectly suitable for a p-2-p file sharing system where tens of peers exchange thousands of blocks and they do not know beforehand which ones they will end up exchanging. Therefore, our system yields up to one-to-two orders of magnitude improvement in terms of both computation and communication (40 s vs. 42 min, 1.6 MB vs. 200 MB). Thus, for the first time, a provably secure (and privacy-respecting when payments are made using e-cash) fair exchange protocol can be used in real bartering applications (e.g., BitTorrent) [14] without sacrificing performance. 相似文献
8.
为了准确预测图书馆借阅量,本文提出基于支持向量机的图书馆借阅量时序预测方法,支持向量机能有效解决非线性、高维、小样本等问题,并采用遗传算法选取合适的支持向量机训练参数,以此增加支持向量机的泛化能力。首先提出了支持向量机预测模型,并进行实例分析,将华北科技学院图书馆流通部1997-2007年度借阅量作为本文的实验数据。实验结果表明支持向量机的图书馆借阅量预测效果优于径向基(Radial Basis Function,RBF)神经网络。 相似文献
9.