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1.
The liquid crystalline transitions of two kinds of smectic polyesters with different molecular weights were investigated by DSC, polarized microscopy and X-ray diffraction. The molecular weight affects the transitions significantly for these two kinds of polyesters. With a high enough molecular weight, both poly (pentamethylenep,p-bibenzoate) and poly(hexamethylenep,p-bibenzoate) exhibit an enantiotropic smectic phase, but the two endothermic transition peaks of the DSC heating curve seem to overlap. The polyesters tend to exhibit a monotropic smectic phase as the molecular weight decreases. From the DSC cooling curve, the isotropic-smectic transition can be seen more clearly. As the molecular weight decreases, the smectic order decrease significantly. The molecular weight affects the transitions in a different way for these two different kinds of polyesters.  相似文献   
2.
与传统投票相比较, 电子投票拥有许多优势, 也存在重要的安全问题. 电子投票的全隐私性是评估投票方案安全的重要指标, 它是指对投票者的隐私保护和候选者的隐私保护, 特别是落选者的得票数的保护. 利用可验证秘密共享的思想提出了一个安全多方排序协议, 并将它运用到电子投票中, 设计了一个新的安全的电子投票协议, 本协议具有全隐私性.  相似文献   
3.
介绍了利用辉光放电光谱法分析掺杂纳米硅薄膜通过优化辉光光源激发参数、计算标准样品的溅射率,建立了掺杂纳米硅薄膜的定量表面分析方法.方法应用于实际掺杂纳米硅薄膜样品的分析,并将分析深度剖析结果与表面形貌仪的结果进行了对照.实验结果表明,本分析方法快速、准确,具有实际应用价值.  相似文献   
4.
Multilayer piezoelectric ceramics must be sintered in a reducing atmosphere, preventing oxidation of the inner base metal. Plate-like textured (Ba, Ca)(Ti, Sn, Hf)O3 ceramics with a <001> preferred orientation were successfully developed at a low oxygen partial pressure (PO2:10?8 atm) using a BaTiO3 (BT) template with sintering temperatures < 1300 °C, which is beneficial for multilayer applications using base metal co-firing with ceramics. When adding the 3 wt% BT template, the proposed samples had a Lottgering factor of 84 %, piezoelectric coefficients d33 = 324 pC/N, -d31 = 122 (pC/N), and Qm = 452, and the strain values increased from 0.07 % for the randomly oriented ceramics to 0.115 % at 20 kV/cm for the textured ceramics, confirming that the texturing behavior assisted the grain growth and improved both the soft and hard behaviors and insulation resistance of the proposed lead-free ceramics. These findings make a significant contribution to the production of high-power piezoelectric components.  相似文献   
5.
This paper proposed the techniques of ontology and linguistics to develop a fully-automatic annotation technique, coupling with an automatic ontology construction method, could play a key role in the development of Semantic Portals. An ontology-supported portal architecture: OntoPortal was proposed according to this technique, in which three internal components Portal Interface, Semantic Portal, and OntoCrawler was integrated to rapidly and precisely collect information on Internet and capture true user’s intention and accordingly provide high-quality query answers to meet the user requests. This paper also demonstrated the OntoPortal prototype which defined how a semantic portal is interacting with the user by providing five different types of interaction patterns such as including keyword search, synonym search, POS (Part-of-Speech)-constrained keyword search, natural language query, and semantic index search. The preliminary experiment outcomes proved the technology proposed in this paper to be able to really up-rise the precision and recall rates of webpage searching and accordingly showed that it can indeed retrieve better semantic-directed information to meet user requests.  相似文献   
6.
The focus of this paper is customer order scheduling (COS) problem, where each order consists of a set of jobs that must be shipped as one batch at the same time. In COS each job is part of a customer order and the make-up of the jobs in the order are pre-specified. Most of the existing research deals with COS in a single machine or in a parallel machine shop for developing an optimal solution. COS is common in a normal job shop, and the more complex the shop, the more complex the scheduling. Most existing research has focused on trying to reduce the completion time of the batch. That is, the focus is only on the point in time the last job is finished, while ignoring the actual duration of the jobs within the same order. The longer it takes to complete all the jobs within an order the more it increases the stock of finished goods and the more it deteriorates the efficiency of the logistics and the supply chain management.A new dispatching rule, referred to as Minimum Flow Time Variation (MFV), has been proposed for COS in a normal job shop, in order to reduce the total time it takes to complete all jobs within the same order. That is, the individual completion times of all jobs for the same customer order will be controlled in order to improve the shipping performance. In the simulation test and statistical analysis, the level of work in process (WIP) under the MFV rule in the finished goods warehouse is reduced by more than 70% compared to any other method. The MFV method will efficiently reduce the stock level of finished goods, and controls the waiting time required before they can be shipped. Depending on the environmental factors, the performance of our proposed method will become increasingly significant the more complex the system.  相似文献   
7.
In this paper, Ca6BaP4O17:Sm3+ and Li+ co-doped Ca6BaP4O17:Sm3+ phosphors were synthesized in air and argon atmospheres using a solid-state reaction method. The phosphor morphologies and crystal structure were studied using scanning electron microscopy and X-ray diffraction, respectively. The emission and absorption characteristics were investigated using photoluminescence emission spectroscopy and diffuse reflectance spectroscopy. The surface states and composition of phosphor were investigated using X-ray photoelectron spectroscopy. The emission integrated intensities of the phosphors sintered in an argon atmosphere increased 3.5 fold than the ones sintered in air atmosphere, with Li+ ions becoming embedded in the lattice of the Ca6BaP4O17:Sm3+ phosphor. This occurs because there are fewer defect/oxygen vacancies and less of the secondary phase forms, leading to better Sm3+ emission. The results suggest that sintering a mixture of the raw materials of a phosphor in an argon atmosphere is a good approach for synthesizing Ca6BaP4O17:Sm3+ phosphor powders. The color purity and CIE values of an optimized phosphor sample sintered in an argon atmosphere with an Li+ ion compensator were calculated to be ~ 99.6% and (0.612,0.386) in the orange–red region under 405-nm excitation, respectively. Moreover, the solid solubility of Sm3+ ions in the Ca6BaP4O17 host can be enhanced by using an argon atmosphere in the synthesis process.  相似文献   
8.
This study designed and developed a novel cloud information agent system with Web service techniques. This paper not only explores related technologies for establishing Web service platforms, but also investigates the construction of cloud interactive diagrams using the extremely efficient operating methods towards extensively and seamlessly integrating backend information agent systems in the context of the Internet. Specifically, this paper provides an example of an energy-saving multi-agent system, and produces results regarding the completeness and feasibility of the proposed architecture. This is aimed at building related information agent mechanisms to support energy-saving information processing and decision-making in order to focus on a system design of succinctness, cooperation, modularizing, and easy maintenance, with emphasis on computing power with many Web service techniques. The deep and complete system development, display, and corresponding experiments and comparisons show that the research results are highly successful.  相似文献   
9.
Web service and ontology techniques are presented herein for supporting an energy-saving and case-based reasoning information agent. The proposed system is the first energy-saving and case-based reasoning information agent with Web service and ontology techniques in a cloud environment; the proposed architecture is also the first multi-agent structure of an energy-saving information system in a practical environment. Not only can it explore related technologies to establish a Web service platform, but it can also study how to construct cloud interactive diagrams to employ Web service techniques for extensively and seamlessly integrating energy-saving and a case-based reasoning information agent on the Internet. The complete in depth system development, display, and corresponding experiments and comparisons show that the research results not only attest to the feasibility of the proposed architecture, but are also highly successful; on average, 40% of the data queries can be answered by the proposed system, and its rate of correct data solutions is around 85.1%, leaving about 60% of the queries for the backend system to take care of, which can effectively alleviate the overloading problem usually associated with a backend server. Finally, the system is put into a practical environment; after 8 months of experiments, the total energy-saving is 22.44%.  相似文献   
10.
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