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81.
Uber used a disruptive business model driven by digital technology to trigger a ride-sharing revolution. The institutional sources of the company’s platform ecosystem architecture were analyzed to explain this revolutionary change.Both an empirical analysis of a co-existing development trajectory with taxis and institutional enablers that helped to create Uber’s platform ecosystem were analyzed.The analysis identified a correspondence with the “two-faced” nature of ICT that nurtures un-captured GDP. This two-faced nature of ICT can be attributed to a virtuous cycle of decline in prices and an increase in the number of trips.We show that this cycle can be attributed to a self-propagating function that plays a vital role in the spinoff from traditional co-evolution to new co-evolution. Furthermore, we use the three mega-trends of ICT advancement, paradigm change and a shift in people’s preferences to explain the secret of Uber’s system success.All these noteworthy elements seem essential to a well-functioning platform ecosystem architecture, not only in transportation but also for other business institutions. 相似文献
82.
《Energy Policy》2016
Improving energy productivity is one of the most cost-effective ways to achieve a sustainable development target. The existing literature has shown some factors that have driven the improvement in China’s energy productivity. However, these studies do little to tackle the role of Chinese local officials. Political promotions can be seen as the most important career incentive for Chinese local officials. Hence, we intend to study whether energy productivity affects Chinese local officials’ promotions in this paper. The data of position changes for the 31 provincial governors during 1978‐2012 are utilized. We adopted probit models to empirically examine the correlation between provincial governors’ political promotions and energy productivity. The empirical results demonstrate that (1) energy productivity has a significantly positive impact on provincial governors’ political promotions in China, meaning that the provincial governors have the momentum to improve energy productivity; and (2) the effect of energy productivity on provincial governors’ political promotions has evolved, dynamically changing along with the transformation of the economic growth mode and the adjustment of the local officials’ promotion mechanism. The results are helpful in understanding the drivers of the improvement in China’s energy productivity and provide insightful implications for conducting energy policy in China. 相似文献
83.
Accurate modeling of driver decisions in dilemma zones (DZ), where drivers are not sure whether to stop or go at the onset of yellow, can be used to increase safety at signalized intersections. This study utilized data obtained from two different driving simulator studies (VT-SCORES and NADS datasets) to investigate the possibility of developing accurate driver-decision prediction/classification models in DZ. Canonical discriminant analysis was used to construct the prediction models, and two timeframes were considered. The first timeframe used data collected during green immediately before the onset of yellow, and the second timeframe used data collected during the first three seconds after the onset of yellow. Signal protection algorithms could use the results of the prediction model during the first timeframe to decide the best time for ending the green signal, and could use the results of the prediction model during the first three seconds of yellow to extend the clearance interval. It was found that the discriminant model using data collected during the first three seconds of yellow was the most accurate, at 99% accuracy. It was also found that data collection should focus on variables that are related to speed, acceleration, time, and distance to intersection, as opposed to secondary variables, such as pavement conditions, since secondary variables did not significantly change the accuracy of the prediction models. The results reveal a promising possibility for incorporating the developed models in traffic-signal controllers to improve DZ-protection strategies. 相似文献
84.
The Iterated Prisoner’s Dilemma (IPD) game has been commonly used to investigate the cooperation among competitors. However, most previous studies on the IPD focused solely on maximizing players’ average payoffs without considering their risk preferences. By introducing the concept of income stream risk into the IPD game, this paper presents a novel evolutionary IPD model with agents seeking to balance between average payoffs and risks with respect to their own risk attitudes. We build a new IPD model of multiple agents, in which agents interact with one another in the pair-wise IPD game while adapting their risk attitudes according to their received payoffs. Agents become more risk averse after their payoffs exceed their aspirations, or become more risk seeking after their payoffs fall short of their aspirations. The aspiration levels of agents are determined based on their historical self-payoff information or the payoff information of the agent population. Simulations are conducted to investigate the emergence of cooperation under these two comparison methods. Results indicate that agents can sustain a highly cooperative equilibrium when they consider only their own historical payoffs as aspirations (called historical comparison) in adjusting their risk attitudes. This holds true even for the IPD with a short game encounter, for which cooperation was previously demonstrated difficult. However, when agents evaluate their payoffs in comparison with the population average payoff (called social comparison), those agents with payoffs below the population average tend to be dissatisfied with the game outcomes. This dissatisfaction will induce more risk-seeking behavior of agents in the IPD game, which will constitute a strong deterrent to the emergence of mutual cooperation in the population. 相似文献
85.
"昭君出塞"故事源于汉代,绵延流传,元青花《昭君出塞》罐表现的即为"昭君出塞"故事题材。元青花《昭君出塞》罐具有鲜明的艺术特征,同时,亦具有丰富而深邃的主题思想内涵。 相似文献
86.
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88.
《Journal of Location Based Services》2013,7(3-4):141-178
ABSTRACTDisclosing the current location of a person can seriously affect their privacy, but many apps request location information to provide location-based services. Simultaneously, these apps provide only crude controls for location privacy settings (sharing all or nothing). There is an ongoing discussion about rights of users regarding their location privacy (e.g. in the context of the General Data Protection Regulation – GDPR). GDPR requires data collectors to notify users about data collection and to provide them with opt-out options. To address these requirements, we propose a set of user interface (UI) controls for fine-grained management of location privacy settings based on privacy theory (Westin), privacy by design principles and general UI design principles. The UI notifies users about the state of location data sharing and provides controls for adjusting location sharing preferences. It addresses three key issues: whom to share location with, when to share it, and where to share it. Results of a user study (N=23) indicate that (1) the proposed interface led to a greater sense of control, that (2) it was usable and well received, and that (3) participants were keen on using it in real life. Our findings can inform the development of interfaces to manage location privacy. 相似文献
89.
对于给定的树脂、颜填料体系,采用丹尼尔流动点理论对分散剂进行定性选择和用量试验,并将设计配方推广至生产应用。 相似文献
90.
《Drug development and industrial pharmacy》2013,39(11):1272-1281
The aim of this work was a preliminary study of the “in-process” amorphization of clopidogrel hydrogensulfate (CLP) as model drug during the production of tablets as dosage form. A solvent method was used for amorphization and the crystalline phase of CLP was detected by differential scanning calorimetry; the physical parameters of fresh and stored tablets were investigated. For the amorphous form, Aerosil 200 was selected as crystallization inhibitor as the most suitable of eight auxiliary agents. The optimum composition of the product for amorphization in the scaling-up process (100-fold) was 7 parts of CLP to 3 parts of Aerosil 200. In this scaled-up product, the amorphous CLP was fixed on the surface of microcrystalline cellulose. The tablet form further stabilized the amorphous form. Finally, the steps of an “in-process” amorphization are given as a protocol, which can promote stabilization of an amorphized active pharmaceutical ingredient. 相似文献