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51.
We consider the problem of pricing for bandwidth provisioning over a single link, where users arrive according to a known stochastic traffic model. The network administrator controls the resource allocation by setting a price at every epoch, and each user’s response to the price is governed by a demand function. We formulate this problem as a partially observable Markov decision process (POMDP), and explore two novel pricing schemes––reactive pricing and spot pricing––and compare their performance to appropriately tuned flat pricing. We use a gradient-ascent approach in all the three pricing schemes. We provide methods for computing unbiased estimates of the gradient in an online (incremental) fashion. Our simulation results show that our novel schemes take advantage of the known underlying traffic model and significantly outperform the model-free pricing scheme of flat pricing. 相似文献
52.
3G时代是移动多媒体时代,但是移动多媒体时代并不会等着3G的来临才出现,全球的移动运营商已在2.5G网络上提供移动内容服务并在应对由内容计费带来的新挑战。明确了由于移动内容服务在移动网络中的发展给计费模式带来的挑战,并讨论了计费模式在过渡期的发展,其中还介绍了一些欧洲运营商的经验:它们正面临的问题以及采取的应对方法。 相似文献
53.
54.
随着我国油气管理体制改革的不断推进,原来捆绑经营的地下储气库(以下简称储气库)将与管道逐步实现业务分离、财务独立乃至产权独立,如何做好储气服务的经营,便成为储气库运营企业亟待思考并解决的问题。为此,以美国储气库运营企业为例,系统分析了其在天然气市场化改革前后管理体制、服务类型和经营策略的变化,进而结合我国储气库业务经营中的关键因素和现存问题,对我国储气库企业的经营提出了建议。结论认为:①美国天然气市场化改革之后,传统的储气服务商通过设立子公司的形式实现了管输与储气的财务分离和经营统一,新建储气库通过开放季的形式进行预售从而锁定客户,将注采能力作为经营重点加强管理,向老客户提供优先续约权从而兼顾公平与效益;②我国的储气库经营还面临着现行储转费测算方法难以反映储气库实际运行成本、对注采能力重要性的认识有待加强等储多问题;③我国储气库经营企业应建立新的储气服务费定价机制,加强对注采能力的管理和经营,将城市燃气企业作为重点用户加强管理并与之深入合作,在合同设计中对气质、注采能力分配等关键参数进行明确规定,进一步细化服务细则。 相似文献
55.
This paper explores analytical Radio Resource Management models where the relationship between users and services is mapped
through utility functions. Compared to other applications of these models to networking, we focus in particular on specific
aspects of multimedia systems with adaptive traffic, and propose a novel framework for describing and investigating dynamic
allocation of resources in wireless networks. In doing so, we also consider economic aspects, such as the financial needs
of the provider and the users’ reaction to prices. As an example of how our analytical tool can be used, in this paper we
compare different classes of RRM strategies, e.g., Best Effort vs. Guaranteed Performance, for which we explore the relationships
between Radio Resource Allocation, pricing, provider’s revenue, network capacity and users’ satisfaction. Finally, we present
a discussion about Economic Admission Control, which can be applied in Best Effort scenarios to further improve the performance.
Part of this work has been presented at the conference ACM/IEEE MSWiM 2004, Venice (Italy).
Leonardo Badia received a Laurea degree (with honors) in electrical engineering and a Ph.D. in information engineering from the University
of Ferrara, Italy, in 2000 and 2004, respectively. He was a Research Fellow at the University of Ferrara from 2001 to 2006.
During these years, he also had collaborations with the University of Padova, Italy, and Wireless@KTH, Royal Institute of
Technology, Stockholm, Sweden. In 2006, he joined the “Institutions Markets Technologies” (IMT) Institute for Advanced Studies,
Lucca, Italy, where he is currently a Research Fellow. His research interests include wireless ad hoc and mesh networks, analysis
of transmission protocols, optimization tools and economic models applied to radio resource management.
Michele Zorzi received a Laurea degree and a Ph.D. in electrical engineering from the University of Padova in 1990 and 1994, respectively.
During academic year 1992–1993, he was on leave at UCSD, attending graduate courses and doing research on multiple access
in mobile radio networks. In 1993 he joined the faculty of the Dipartimento di Elettronica e Informazione, Politecnico di
Milano, Italy. After spending three years with the Center for Wireless Communications at UCSD, in 1998 he joined the School
of Engineering of the University of Ferrara, Italy, where he became a professor in 2000. Since November 2003 he has been on
the faculty at the Information Engineering Department of the University of Padova. His present research interests include
performance evaluation in mobile communications systems, random access in mobile radio networks, ad hoc and sensor networks,
energy constrained communications protocols, and broadband wireless access. He was Editor-In-Chief of IEEE Wireless Communications,
2003–2005, and currently serves on the Editorial Boards of IEEE Transactions on Communications, IEEE Transactions on Wireless
Communications, Wiley’s Journal of Wireless Communications and Mobile Computing, and ACM/URSI/Kluwer Journal of Wireless Networks,
and on the Steering Committee of the IEEE Transactions on Mobile Computing. He has also been a Guest Editor of special issues
in IEEE Personal Communications (Energy Management in Personal Communications Systems) and IEEE Journal on Selected Areas
in Communications (Multimedia Network Radios). 相似文献
56.
为了解决IT企业中服务价格无统一计算方法,多由施工人员自行确定的问题,提出了一种解决IT企业服务定价的方法。该方法先用模糊C均值算法对既往的原始价格数据进行聚类分析,再按聚类结果对每类数据分别进行多元线性回归分析,并建立服务定价的数学模型,在此模型的基础上,估算出服务的价格。最后通过数据验证结果证明,此方法的定价效果较为理想,具有可行性和推广价值。 相似文献
57.
Pricing and inventory control in a competing environment, as separate entities, have attracted much attention from academics and practitioners. However, integrating these decisions in a competitive setting has not been significantly analyzed by academics, but is of great significance to practitioners. In this study, the joint decision on price and inventory control of a deterioration product is investigated in a duopoly setting. We consider two competing supply chains, each consisting of one manufacturer and one retailer. Each manufacturer, as the leader of their supply chain determines the wholesale price to maximize their profit, while the retailer as the follower should determine the retail price and inventory cycle to maximize his or her profit. Using a game theoretic approach, we formulate in-chain, and chain-to-chain competition as a bi-level programming problem, and analyze Stackelberg–Nash equilibrium of the problem. Furthermore, two versions of a nested algorithm are proposed to obtain the equilibrium. Both versions employ a modified threshold-accepting (TA) algorithm to solve the first level of the problem. However, while the first version utilizes the modified TA algorithm to deal with the second level of the problem, the second version applies a differential evolution (DE) approach. Eventually, a numerical study is carried out not only to compare two developed versions of the algorithm, but also to implement the sensitivity analysis of main parameters. Based on numerical experiments, although the accuracy of both versions of algorithm are alike, using TA is more computationally efficient than using DE. Furthermore, despite the permissibility of partial backlogging, it has never occurred in equilibrium points due to in-chain and chain-to-chain competition. 相似文献
58.
59.
随着国家《建设工程工程量清单计价规范》的颁布实施,如何做好施工合同管理可能遇到一些新问题。本文就清单计价合同的订立、履行及索赔事件处理进行了探讨。 相似文献
60.
A problem that always annoys building employers and their consultants when drafting building contracts is whether it is more cost efficient to retain certain risks with themselves or to transfer the same to contractors, and it has long been a difficulty to accurately estimate the cost for transferring risks to the other contract party. It is a very common market practice to remove contractors’ entitlement to extension of time due to inclement weather, and in view of the significant impacts that inclement weather posed on construction progress, it would be helpful to assess the associated costs for such risk allocation exercises in order to ensure that it is a cost-effective transaction. The costs for these potential weather-caused delays are priced by contractors in their returned tenders. This risk-pricing behavior is affected by the contractor’s risk perception and risk attitude. However, merely working out contractors’ risk perception and risk attitude patterns is inadequate, as they may vary in accordance with different organizational sizes and project backgrounds. Therefore, further studies should be carried out on the implications of project information, such as project value and contract period, on different-sized contractors’ risk behaviors. In this research, a questionnaire survey was conducted to investigate the weather-risk-pricing behavioral patterns of various-sized contractors under different given project scenarios. The survey revealed that the impacts of project value and contract period (and, thus, the intensity of work and scale of exposure to weather risk) were significant on contractors’ risk behaviors, and these impacts varied in accordance with different organizational sizes. The medium-sized contractors’ pricing behaviors were rather constant under different project values and contract periods, while both small and large contractors behaved differently when the intensity of work and scale of risk exposure varied. Despite the fact that contractors of various sizes behaved differently in some given scenarios, the number of days of delaying cost allowed by them in returned tenders were generally less than the actual number of days of inclement weather affecting work. 相似文献