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81.
For the first time in literature, this study compares the process-induced chemical reactions in three industrially relevant green vegetables: broccoli, green pepper and spinach treated with thermal and high pressure high temperature (HPHT) processing. Aiming for a fair comparison, the processing conditions were selected based on the principle of equivalence. A comprehensive integration of MS-based metabolic fingerprinting techniques, advanced data preprocessing and statistical data analysis has been implemented as untargeted/unbiased multiresponse screening tool to uncover changes in the volatile fraction. For all vegetables, thermal processing, compared to HPHT, seems to enhance Maillard and Strecker degradation reaction, triggering the formation of furanic compounds and Strecker aldehydes. In most cases, high pressure seems to accelerate (an)aerobic thermal degradation of unsaturated fatty acids leading to the formation of aliphatic aldehydes and ketones. In addition, both thermal and HPHT processing accelerated the formation of sulfur-containing compounds. This work demonstrated that the approach is effective in identifying and comparing different process-induced chemical changes, adding depth to our perspective in terms of studying a highly complex chemical changes occurring during food processing.  相似文献   
82.
The area under the ROC curve, or AUC, has been widely used to assess the ranking performance of binary scoring classifiers. Given a sample, the metric considers the ordering of positive and negative instances, i.e., the sign of the corresponding score differences. From a model evaluation and selection point of view, it may appear unreasonable to ignore the absolute value of these differences. For this reason, several variants of the AUC metric that take score differences into account have recently been proposed. In this paper, we present a unified framework for these metrics and provide a formal analysis. We conjecture that, despite their intuitive appeal, actually none of the variants is effective, at least with regard to model evaluation and selection. An extensive empirical analysis corroborates this conjecture. Our findings also shed light on recent research dealing with the construction of AUC-optimizing classifiers.  相似文献   
83.
This study focuses on examining color effects of perceived speed in an individual noncompetitive sport context, treadmill running. In addition, the presence of individual trends for color effects are inspected by observing the connection of color effects in a sport‐specific video rating task with those found in an individual color association task. For this, 32 participants rated the perceived running speed of 48 videos depicting runners on a treadmill at seven different speed settings. Furthermore, participants rated a range of additional sport‐specific performance parameters. The runners in the video were shown wearing either a red, blue, or gray jersey, gray being used to strengthen the cover story. As a secondary task, the participants performed a modified Stroop task to assess implicit color associations. The results showed a significant color effect for speed; runners depicted in red were perceived as running at higher speeds compared to blue. No significant color effects were found for the other sport‐specific parameters. Finally, there was no significant covariate effect of the modified Stroop task for the speed perception color effect. These findings indicate that, in situations in which speed must be judged, red might be perceived as going faster.  相似文献   
84.
Clean combustion processes are of paramount importance in the transition of the energy system towards increased sustainability. In an attempt to partially replace conventional fossil fuels, bio-derived oxygenates attract rising attention as alternative transportation fuels. Among this class of fuels, cyclic structures that can be derived from cellulosic biomass are particularly interesting. Here we present a study of premixed, laminar low-pressure flames of 2-methyltetrahydrofuran (2-MTHF) with an equivalence ratio of ? = 1.7 at 40 mbar. Time-of-flight molecular-beam mass spectrometry (MBMS) with electron ionization (EI) was used to analyze and quantify mole fraction profiles of reactants, products, and most intermediate species including radicals involved in the combustion process. As a valuable complement, MBMS using single-photon ionization (PI) by vacuum ultraviolet radiation permitted isomer identification as well as independent concentration information under similar flame conditions. A detailed combustion model for 2-MTHF was developed, and the flame structure and species information were examined in conjunction with these experiments.  相似文献   
85.
Replies to commentary by J. Mills (see record 2008-03991-014) on the current authors' original article (see record 2006-00627-003) regarding posttraumatic stress disorder and the question of representability. In the first part of our answer, we will clarify certain of our ideas in the light of Mills's critical remarks. In the second part, we want to address what we consider to be the main problem in matters of posttraumatic stress disorder (PTSD), that is, the question of representability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
87.
In modern programming languages, concurrency control can be traced back to one of two different schools: actor-based message passing concurrency and thread-based shared-state concurrency. This paper describes a linguistic symbiosis between two programming languages with such different concurrency models. More specifically, we describe a novel symbiosis between actors represented as event loops on the one hand and threads on the other. This symbiosis ensures that the invariants of the actor-based concurrency model are not violated by engaging in symbiosis with multithreaded programs. The proposed mapping is validated by means of a concrete symbiosis between AmbientTalk, a flexible, domain-specific language for writing distributed programs and Java, a conventional object-oriented language. This symbiosis allows the domain-specific language to reuse existing software components written in a multithreaded language without sacrificing the beneficial event-driven properties of the actor concurrency model.  相似文献   
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89.
Effective network monitoring is vital for a growing number of control and management applications typically found in present-day networks. The ever-increasing link speeds and the complexity of monitoring applications’ needs have exposed severe limitations of existing monitoring techniques. A majority of the current monitoring tasks require only a small subset of all observed packets, which share some common properties such as identical header fields or similar patterns in their data. In order to capture only these useful packets, a large set of expressions needs to be evaluated. This evaluation should be done as efficiently as possible when monitoring multi-gigabit networks. To speed up this packet classification process, this article presents different packet filter optimization techniques. Complementary to existing approaches, we propose an adaptive optimization algorithm which dynamically reconfigures the filter expressions based on the currently observed traffic pattern. The performance of the algorithms is validated both analytically and by means of the implementation in a network monitoring framework. The various characteristics of the algorithms are investigated, including their performance in an operational network intrusion detection system.  相似文献   
90.
This paper focuses on the axial impact crushing behaviour of recyclable empty metal beverage cans available in the market. The idea is to make a macro foam (sacrificial cladding structure) out of these cans to protect the main load bearing members of civil engineering structures from the air blast load. Axial drop weight tests have been conducted to understand the crushing characteristics and the corresponding energy absorption of a single empty beverage can in detail. To conduct such tests a small-scale drop weight test set-up has been designed and manufactured. The deformation mechanisms and the corresponding energy absorption of the beverage cans were studied in detail for different initial impact velocities (1.4 m/s, 2.2 m/s, 3.1 m/s, 3.8 m/s, 4.4 m/s and 4.9 m/s). Furthermore, an analytical model is proposed to calculate the crushing parameters of empty metal beverage cans. The results from the analytical model are compared and validated with the experimental results.  相似文献   
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