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41.
Huibiao Zhu Jifeng He Jing Li Jonathan P. Bowen 《Innovations in Systems and Software Engineering》2011,7(3):209-224
Web services have become more and more important in these years, and BPEL4WS (BPEL) is a de facto standard for the web service
composition and orchestration. It contains several distinct features, including the scope-based compensation and fault handling
mechanism. We have considered the operational semantics and denotational semantics for BPEL, where a set of algebraic laws
can be achieved via these two models, respectively. In this paper, we consider the inverse work, deriving the operational
semantics and denotational semantics from algebraic semantics for BPEL. In our model, we introduce four types of typical programs,
by which every program can be expressed as the summation of these four types. Based on the algebraic semantics, the strategy
for deriving the operational semantics is provided and a transition system is derived by strict proof. This can be considered
as the soundness exploration for the operational semantics based on the algebraic semantics. Further, the equivalence between
the derivation strategy and the derived transition system is explored, which can be considered as the completeness of the
operational semantics. Finally, the derivation of the denotational semantics from algebraic semantics is explored, which can
support to reason about more program properties easily. 相似文献
42.
Huibiao Zhu Jifeng He Jing Li Geguang Pu Jonathan P. Bowen 《Innovations in Systems and Software Engineering》2010,6(4):283-298
Web Services have become more and more important in these years, and BPEL4WS (BPEL) is a de facto standard for the web service
composition and orchestration. It contains several distinct features, including the scope-based compensation and fault handling
mechanism. The denotational semantics and operational semantics have been explored for BPEL. The two semantic models should
be consistent. This paper considers the linking of these two semantics. Our approach is to derive the denotational semantics
from operational semantics for BPEL, which aims for the consistency of the two models. Moreover, the derivation can be applied
in exploring the program equivalence easily, especially for parallel programs. 相似文献
43.
Formal Versus Agile: Survival of the Fittest 总被引:1,自引:0,他引:1
Many research have focused on new formal methods, integrating formal methods into agile ones, and assessing the agility of formal methods. This paper proves that formal methods can survive in an agile world; they are not obsolete and can be integrated into it. The potential for combining agile and formal methods holds promise. It might not always be an easy partnership, and succeeding will depend on a fruitful interchange of expertise between the two communities. Conducting a realistic trial project using a combined approach with an appropriate formal methods tool in a controlled environment will help assess the effectiveness of such an approach. 相似文献
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针对坝体位移时间序列中出现数据跳跃的现象,基于动力学互关因子指数法与云模型理论,提出了一种能准确辨识大坝位移时间序列中动力突变盲点位置的诊断方法,并构建了考虑动力突变盲点的混凝土坝位移安全监控模型。基于不确定性动力系统对大坝位移的演化分析,综合运用相空间重构、云模型及小波分析等数值处理方法,从所辨识数值序列中的动力突变盲点出发,研究了对大坝工作性态转异进行预测诊断的方法。工程实例表明,该方法能找准对应位移的动力突变盲点,可避免动力突变盲点对大坝位移序列的不利影响,提高了大坝位移安全监控模型的可靠性和科学性。 相似文献
48.
With the ever-increasing use of pharmaceuticals and the relatively high risk of developing drug allergies, particularly for patients in hospitals and for ambulatory patients with a history of drug allergy, the need to develop in vitro assays for drug allergy is great. In the early 1970's a mast cell technique was developed for diagnosis of drug allergies. A PRIST inhibition assay has also recently been developed to detect IgE antibodies to drug allergens. This test has also been referred to as the Total IgE Inhibition Test by Specific Drug Allergen, and is a variant of the in vitro RAST Test. In vitro mast cell and IgE inhibition tests are applied for identification of drug and chemical allergens and for their cautious clinical trial to prevent future drug and chemical reactions. Over the last eight years, over 1,300 patients were examined utilizing the mast cell technique. Over 100 drugs were tested, with penicillin, barbiturates, "caine" derivatives and sulfonamides most frequently employed. Of 270 patients with well-defined drug reactions, 190 (70 per cent) gave a positive response to the mast cell test. Eighty-five per cent of sera tested with Type I reactions gave a mast cell response. Of these, a group of 30 patients was studied with PRIST inhibition as well. Procedures for comparative testing of necessary drugs and/or chemicals in cases of high anaphylaxis risk of reaction in the clinical setting, hospital or office are included in the study as well as individual case reports. Mast cell assay coupled with IgE inhibition has been successfully used to diagnose drug and chemical allergic reactions. The incidence of positivity is high when the offending drug causes a Type I allergic reaction. The cases reported indicate that both the Mast Cell and the PRIST inhibition assays are useful for diagnosing and setting the clinical treatment and clinical course of the patient. The mast cell assay would be potentially employed for patient use in hospitals where the incidence of drug allergy is highest and for occupational health in the chemical industry. The greatest potential would be in outpatient care applied to patients with multiple drug allergies in the selection of safe drugs (test negative by both methods, and other clinical studies) for future drug usage. 相似文献
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A new method is described that enables the simultaneous detection of 6-3H thymidine incorporation and acid phosphatase activity in the same tissue section. Histochemically, naphthol AS B1 released by tissue based acid phosphatase activity from the substrate naphthyl AS B1 phosphoric acid is coupled with a range of diazonium salts to produce insoluble azo dyes. The azo dye tests result in a particulate localization of lysosomal acid phosphatase and also label diffuse sources associated with cell death. The tests selected permit the application of photographic emulsion without the necessity of an inert barrier layer to separate the emulsion from the histochemically treated cryosections. The localization of 6-3H thymidine incorporation and cell death in mouse thymus and duodenum is demonstrated and comparative counts estimating the distribution of 6-3H thymidine incorporation and hydrolase labelled cell death in the thymus are presented. Young mouse thymus (5 weeks) was found to contain 1·36 ± 0·12% dying cells and 6·78 ± 0·03% thymidine incorporating cells, whilst old mouse thymus (53 weeks) was found to contain 2·34 ± 0·6% dying cells and 5·29 ± 0·37% thymidine incorporating cells. 相似文献