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61.
In the design of a wastewater treatment plant, engineers must estimate the future population that the plant will need to serve. When the population growth is uncertain, modular design can reduce up-front capital costs, operating costs and total expected present value costs. Models based on real option theory can provide insights to engineers/decision-makers that will not arise from standard net present value analysis. We consider a municipality faced with a plant expansion decision required to meet the demand of significant, uncertain growth. We present a model that optimises the size of the plant and its maximum modular size. The optimisation requires that multiple solutions be calculated at the decision time for the staged expansion. We utilise a moment matching technique to approximate the solution of the Asian-like option. The results show that as the uncertainty increases, a modular plant can save significant total costs for the municipality.  相似文献   
62.
This paper presents a comprehensive decision-making framework for evaluating a portfolio of IT projects. A problem of IT project selection with and without project interdependencies is considered. The problem is subject to maximum project funding budget constraint. When IT project portfolio contains independent projects, a dynamic programming (DP) solution procedure is proposed to efficiently solve the portfolio of IT projects' problem. However, when IT project portfolio contains project interdependencies, a mixed integer programming (MIP) approach is needed to solve the problem optimally. Experiments and results using simulated data using Monte Carlo simulation are provided. The results indicate that a large set of project selection problems containing up to 60 projects can be solved easily using the proposed decision-making framework.  相似文献   
63.
This paper presents a method for evaluating investments in decentralized renewable power generation under price un certainty. The analysis is applicable for a client with an electricity load and a renewable resource that can be utilized for power generation. The investor has a deferrable opportunity to invest in one local power generating unit, with the objective to maximize the profits from the opportunity. Renewable electricity generation can serve local load when generation and load coincide in time, and surplus power can be exported to the grid. The problem is to find the price intervals and the capacity of the generator at which to invest. Results from a case with wind power generation for an office building suggests it is optimal to wait for higher prices than the net present value break-even price under price uncertainty, and that capacity choice can depend on the current market price and the price volatility. With low price volatility there can be more than one investment price interval for different units with intermediate waiting regions between them. High price volatility increases the value of the investment opportunity, and therefore makes it more attractive to postpone investment until larger units are profitable.  相似文献   
64.
This paper presents a valuation study of operational flexibility in the complex Brazilian Power System. Thermopower plants represent operational flexibility for the national system operator provided they can be dispatched in dry periods to supply part of the load when reservoir waters are too low. Deficit costs can be avoided as a result.

We have adopted a real options approach to calculate the fair value of a financial subsidy to be paid to thermal generators for their availability to the system. A financial subsidy is mandatory for their economic feasibility and, therefore, for increased thermopower capacity in the Brazilian Power System. This is why this policy is currently being studied by Brazil's federal government.

In order to illustrate our modeling we have run the model for the southeast subsystem. We found a flexibility value of US$4.52 billion, which represents US$497/MW per year. This means that a 100 MW thermopower plant should receive US$49,700 for each year of its economic lifetime as a fair premium incentive to investments.  相似文献   

65.
The 300 mm wafer copper electrochemical deposition (ECD) process for dual damascene metallization of semiconductor advanced interconnects is critically reviewed and the breakthroughs that enable further scaling of this process are examined. Special emphasis is placed on analyzing the critical issues, such as barrier/seed options, terminal effect and future plating prospects for this technology. The smallest plateable feature size values are estimated for different metallization integration schemes, such as conventional Physical Vapor Deposited (PVD) TaN/Ta/Cu, hybrid RuTa/Cu, CuMn (8%) self-forming barrier/seed, and Plasma-Enhanced Atomic Layer Deposition (PEALD) Ru, limiting the allowed maximum sheet resistance to 14 Ohms/sq for the Cu-based seeds and the effective maximum filling aspect ratio to 5-6.  相似文献   
66.
The Canadian hydrogen safety program (CHSP) is a project initiative of the Codes & Standards Working Group of the Canadian transportation fuel cell alliance (CTFCA) that represents industry, academia, government, and regulators. The Program rationale, structure and contents contribute to acceptance of the products, services and systems of the Canadian Hydrogen Industry into the Canadian hydrogen stakeholder community. It facilitates trade through fair insurance policies and rates, effective and efficient regulatory approval procedures and accommodation of the interests of the general public. The Program integrates a consistent quantitative risk assessment methodology with experimental (destructive and non-destructive) failure rates and consequence-of-release data for key hydrogen components and systems into risk assessment of commercial application scenarios. Its current and past six projects include Intelligent Virtual Hydrogen Filling Station (IVHFS), Hydrogen clearance distances, comparative quantitative risk comparison of hydrogen and compressed natural gas (CNG) refuelling options; computational fluid dynamics (CFD) modeling validation, calibration and enhancement; enhancement of frequency and probability analysis, and Consequence analysis of key component failures of hydrogen systems; and fuel cell oxidant outlet hydrogen sensor project. The Program projects are tightly linked with the content of the International Energy Agency (IEA) Task 19 Hydrogen Safety.  相似文献   
67.
Bridging digital divide: Efforts in India   总被引:1,自引:0,他引:1  
The fruits of Information Technology sector such as the Internet blue chips, online shopping and nanosecond email have failed to cure century-old malaises like illiteracy, poverty and unemployment in India. The paper presents few facts about digital divide based on global and the USA perspective, its definition and types as global, regional and national, and societal implications. It highlights India in the context of digital divide by discussing its infrastructural bottleneck that includes electricity, IT penetration, teledensity and Internet industry, and its enabling policies to transform India as a knowledge society. It discusses various technology options for connectivity, viz. terrestrial wireless, satellite, wireline, etc. and presents snap shots of select successful projects that made an impact in helping to bridge digital divide in India, viz. passenger reservation system, Akashganga, Akshaya e-centres, Bhoomi, etc. It concludes that creation of Information and Communication Technologies infrastructure and content are the core methodologies, and a national agenda on a C-8 thrust towards: connectivity provision, content creation, capacity augmentation, core technologies creation and exploitation, cost reduction, competence building, community participation and commitment to the deprived and disadvantaged would definitely help in bridging digital divide.  相似文献   
68.
Strategic Resource Development Options in England and Wales   总被引:1,自引:0,他引:1  
This paper describes the options which had to be considered for new water resources in the development of the † National Rivers Authority's water resource strategy for England and Wales. The options included interregional transfers, strategic reservoirs, and a range of unconventional schemes including aquifer recharge, effluent re-use, groundwater abstraction where levels are rising, desalination, and transfer by sea. The main options are described and comparative costs are presented.  相似文献   
69.
We live in a world characterized by evolution—that is, by ongoing processes of development, formation, and growth in both natural and human-created systems. Biology tells us that complex, natural systems are not created all at once but must instead evolve over time. We are becoming increasingly aware that evolutionary processes are ubiquitous and critical for technological innovations as well. This is particularly true for complex software systems because these systems do not necessarily exist in a technological context alone but instead are embedded within dynamic human organizations.The Center for LifeLong Learning and Design (L3D) at the University of Colorado has been involved in research on software design and other design domains for more than a decade. We understand software design as an evolutionary process in which system requirements and functionality are determined through an iterative process of collaboration among multiple stakeholders, rather than being completely specified before system development occurs. Our research focuses on the following claims about software systems embedded within dynamic human organizations: (1) they must evolve because they cannot be completely designed prior to use, (2) they must evolve to some extent at the hands of the users, and (3) they must be designed for evolution.Our theoretical work builds upon our existing knowledge of design processes and focuses on a software process model and architecture specifically for systems that must evolve. Our theories are instantiated and assessed through the development and evolution of domain-oriented design environments (DODEs)—software systems that support design activities within particular domains and that are built specifically to evolve.  相似文献   
70.
Domain-oriented design environments   总被引:2,自引:1,他引:1  
The field of knowledge-based software engineering has been undergoing a shift in emphasis from automatic programming to human augmentation and empowerment. In our research work, we support this shift with an approach that embedshuman-computer cooperative problem-solving tools intodomain-oriented, knowledge-based design environments. Domain orientation reduces the large conceptual distance between problem-domain semantics and software artifacts. Integrated environments support the coevolution of specification and construction while allowing designers to access relevant knowledge at each stage within the software development process.This paper argues thatdomain-oriented design environments (DODEs) are complementary to the approaches pursued withknowledge-based software assistant systems (KBSAs). The DODE extends the KBSA framework by emphasizing a human-centered and domain-oriented approach facilitating communication about evolving systems among all stakeholders. The paper discusses the major challenges for software systems, develops a conceptual framework to address these problems, illustrates DODE with two examples, and assesses the contributions of the KBSA and DODE approaches toward solving these problems.  相似文献   
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