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1.
Small package delivery companies offer services where packages are guaranteed to be delivered within a given time-frame. With variability in travel time, the configuration on the hub-and-spoke delivery network is vital in ensuring a high probability of meeting the service-level guarantee. We present the stochastic p-hub center problem with chance constraints, which we use to model the service-level guarantees. We discuss analytical results, propose solution heuristics, and present the results from computational experiments.  相似文献   
2.
Comments on the report of the Committee on Scientific and Professional Aims of Psychology (1967). Cowan suggests that the report made a faulty analogy between experimental psychology and 19th-century physics. Experimental psychology, with the rest of 20th-century science, relies on a methodology that is bounded by logical inference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
The theory of "alcohol myopia" (C. M. Steele & R. A. Josephs, 1990) suggests that an intoxicated person is disproportionately influenced by immediate, superficial aspects of experience and that effortful, controlled cognitive processing is impaired. The present research examined the effects of alcohol intoxication on social inferences, which refer to perceived reasons, causes, and explanations of events. When asked to focus on the dispositions of others, intoxicated participants tended to exaggerate the extent to which dispositions were influencing behaviors. When asked to focus on the situational conditions in which a behavior took place, intoxicated participants tended to exaggerate the importance of situational influences. The results are consistent with both recent models of social inference and the theory of alcohol myopia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
In this study, we made a novel observation that by introducing a monomeric sugar or a disaccharide into an acetonitrile-water solution, the acetonitrile (ACN) can be separated from water to form a new phase. The two-phase formation triggered by sugar addition was visualized with Sudan I. The ability of different sugars to form an ACN-water two-phase system and the effect of glucose and xylose concentration on the phase separation were studied. The distribution of syringic acid, furfural, para-coumaric acid, ferulic acid and 5-hydroxymethyl furfural in the upper ACN phase and lower water phase was examined. The lower concentration limit for the two-phase formation for glucose and xylose at 1 °C was 15 and 25 g/L, respectively. At higher temperatures, the concentration needed for phase separation increased. Addition of polysaccharides (starch and dextran) did not result in phase separation. The distribution coefficient of the five organic compounds in the ACN-water two-phase system was in the range of 1.7-8.9 when the corresponding sugar concentration was 15-50 g/L. The phase ratio of the five organic compounds in the two-phase system was in the range of 0.1-0.5. The new two-phase system may find applications in the separation of chemicals having different solubility in water and in ACN.  相似文献   
5.
Micro and nanofibrillated cellulose is an essentially one‐dimensional high aspect‐ratio particle material, which can undergo two‐dimensional layer (band) structuring under shear. Controlling the evolving rheological properties in aqueous suspension is essential for industrial applications in composite materials. This study focuses on an as yet considered to be unreported phenomenon of structure hardening under low shear. The timescale of the quasi gelation‐controlled structure formation under low shear is studied using the large gap vane‐in‐cup geometry of the Brookfield viscometer. It is proposed that localized structure forms within continuous shear bands, similar to quasi liquid‐crystal formation. By extrapolating a characteristic structure growth parameter to the rotation speed at which it becomes zero, the strain‐induced structure time constant, tgel, can be obtained as (= f (Ω)) = 1/tgel for the range Ω = 10–100/min. The time constant of low shear structure formation is shown to be separable from the static viscoelastic structure build under oscillation in concentrated composite suspension using plate‐plate geometry, which is manifest by a Weissenberg normal force response on switching to applied shear, when the time constant of structuration tgel is long. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42827.  相似文献   
6.
Replies to comments by J. Prochaska (see record 2010-00152-002) to the author's original critique (see record 2008-13168-006) on the transtheoretical model and smoking cessation. Herzog is disappointed that Prochaska elected not to address the central point of the critique: that the stages of change (SOC) are not qualitatively distinct categories, and that the SOC algorithm systematically underestimates motivation to quit among smokers. All major hypotheses of the TTM depend on the subsidiary hypothesis that the SOC algorithm is a valid measure of motivation to quit smoking. If the SOC is not a valid measure, then the TTM can be expected to produce unsatisfactory results. As for the issues that Prochaska does raise, most of these already are refuted in the critique itself. Herzog did not, as Prochaska suggests, attempt to “prove the null hypothesis.” Rather, his straightforward position is that the TTM as a stage model is not well supported by empirical evidence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
The present study was designed to investigate the effect of ethanol (EtOH) dose on low density lipoprotein (LDL) and platelet composition. Male squirrel monkeys were divided into three groups designated Control, Low, and High EtOH, and fed isocaloric liquid diets containing 0%, 12%, and 24% of calories as EtOH, respectively. After four months of treatment, monkeys fed the 12% alcohol dose had LDL and platelet cholesterol concentrations similar to Controls. By contrast, platelet membranes from High EtOH animals contained significantly more cholesterol which was associated with higher levels of plasma LDL cholesterol and apolipoprotein B. Blood platelet count, size, and mass were similar for all groups and circulating platelet aggregates were absent in the two alcohol cohorts. Despite elevations in platelet cholesterol mass and thromboxane A2 (TXA2) precursor, phospholipid arachidonate, platelet responsiveness, measured as thromboxane formed in response to a collagen challengein vitro, and the cholesterol/phospholipid molar ration, were not significantly altered by high dose alcohol. Normal platelet activity in High EtOH monkeys may have resulted from a significant increase in the platelet phospholipid polyunsaturated/saturated fatty acid ratio and a non-significant increase in platelet phospholipid mass, both of which would have a fluidizing effect on platelet membranes. Our data indicate that low EtOH intake has no effect on platelet composition and function while unfavorable platelet cholesterol enrichment following consumption of high dose ethanol may arise from elevations in plasma LDL. Potentially thrombogenic (TXA2 formation, platelet aggregate formation) consequences of increased platelet cholesterol in squirrel monkeys fed high levels of alcohol may be averted by compensatory physicochemical changes in platelet membrane lipid composition although persistent elevations in circulating LDL may contribute to increased risk of cardiovascular disease.  相似文献   
8.
This paper describes a Teaching Effectiveness Improvement Program based on a multidisciplinary approach and the use of Total Quality Management (TQM) principles. The success of the program underscored the value of cross-functional teams for teaching effectiveness improvement programs. In the case study discussed in this paper, the College of Education, the College of Engineering, the University administration and students participated extensively in framing the requirements and the structure of the program. The program was implemented in the College of Engineering at the University of Cincinnati to improve teaching effectiveness over the last three years. The Plan, Do, Study, Act (PDSA) cycle was used as a framework for improving teaching. The Student evaluations of faculty were used to measure the effectiveness of this program and the results are very promising.  相似文献   
9.
The rudiments of information theoretic methods are introduced and companion papers dealing with solutions of some reliability problems using information theoretic approaches are preluded. Major elements of the communication system are outlined from an information processing point of view. Information is quantified following the work of Shannon. The concepts of uncertainty, self-and mutual information, and entropy are developed as seen at the encoder, channel, and decoder. Channel modeling is demonstrated using a binary symmetric channel as an example. Channel capacity is derived by maximizing transinformation. Elements of coding are described and Shannon's fundamental theorem of discrete noiseless coding is stated. The fundamental relations governing unique decipherability and irreducibility are given and demonstrated by examples. Code efficiency and redundancy are quantified and discussed as system parameters subject to tradeoff. Applications of information theoretic methods in various disciplines are discussed with emphasis on reliability and maintainability. Two unresolved reliability problem areas are identified where, potentially, information theoretic approaches may present a viable solution.  相似文献   
10.
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