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101.
102.
《International Journal of Hydrogen Energy》2019,44(54):28613-28628
The rapidly growing of population in the developing countries and their lack of access to electricity, especially in the remote or rural areas, is causing huge challenges for on energy production. Energy is an enabler and a reliable energy supply is critical to sustainable socio-economic development for any nation. Most of Chad's people live in villages with no particular power supply system. Exploiting renewable energies is the only means of fostering development and improving people's welfare. This paper attempts at proposing an energy profile and storage model for Chad in vast remote towns. The paper addresses the key energy gap that is hindering on the development of such systems, it models and assess the potential on electricity generation and using hydrogen as surplus power storage system. A techno-econo-environmental survey on a solar-wind hybrid system in 25 towns in Chad is undertaken using NASA data and HOMER Software. Several hybrid scenarios of energy production and storage is analyzed. The results showed that in the electricity generation scenario, the average total NPC for the studied stations was $ 48164 and the average LCOE was $0.573. The lowest LCOE was related to Aouzou station with 0.507 $/kWh and the highest LCOE was obtained for Bol station with 0.604 $/kWh. In the simultaneous electricity and hydrogen generation scenario, the cheapest hydrogen ($4.695/kg) was produced in the “Grid” scenario, which was the same for all of the stations, with a total NPC of $2413770. The most expensive hydrogen ($4.707/kg) was generated in the “Grid-Wind” scenario and Bol stations with a total NPC of $2420186. The paper develops cost effective models for all hybrid systems combination for both electricity and hydrogen generation across Chad. These findings could help policy makers, investors and other developmental agencies make informed choices on energy access for sustainable development for rural communities in Sub Saharan Africa. 相似文献
103.
Bong Gu Lee Jun IL Yang Euna Kim Sun Woo Geum Ju-Hyeong Park Min-Kyeong Yeo 《Indoor air》2021,31(5):1553-1562
The advent of high-throughput sequencing methods allowed researchers to fully characterize microbial community in environmental samples, which is crucial to better understand their health effects upon exposures. In our study, we investigated bacterial and fungal community in indoor and outdoor air of nine classrooms in three elementary schools in Seoul, Korea. The extracted bacterial 16S rRNA gene and fungal ITS regions were sequenced, and their taxa were identified. Quantitative polymerase chain reaction for total bacteria DNA was also performed. The bacterial community was richer in outdoor air than classroom air, whereas fungal diversity was similar indoors and outdoors. Bacteria such as Enhydrobacter, Micrococcus, and Staphylococcus that are generally found in human skin, mucous membrane, and intestine were found in great abundance. For fungi, Cladosporium, Clitocybe, and Daedaleopsis were the most abundant genera in classroom air and mostly related to outdoor plants. Bacterial community composition in classroom air was similar among all classrooms but differed from that in outdoor air. However, indoor and outdoor fungal community compositions were similar for the same school but different among schools. Our study indicated the main source of airborne bacteria in classrooms was likely human occupants; however, classroom airborne fungi most likely originated from outdoors. 相似文献
104.
“Join a Meetup Group” (face-to-face study group) has been propagated by Coursera to build rapport and provide mutual support among MOOC learners; however, studies remain scant regarding its effectiveness and sustainability. This interpretive case study documents our facilitation process, key influential factors, as well as student perceived gains in a six-week MOOC study group. Data sources include discussion recordings, end-of-course interviews, goal setting sheets, weekly reflection journals, and researchers' observation notes. Results showed that, cognitively, participants broadened their perspective of thinking, raised cultural awareness, and shared many learning strategies. Affectively, they established a strong sense of community and gained motivation for learning. Participants also increased action tendencies toward trying out Coursera functions, new courses, and learning strategies, and they became more cognizant of the benefits and procedures of the MOOC study group. Our findings suggest that, with proper design and facilitation, face-to-face study group would be a practicable and effective approach to leverage MOOC students' motivation, engagement, and deeper learning. Implications are discussed in terms of potential gains, challenges, key influential factors, as well as future design and implementation of MOOC study groups. 相似文献
105.
Chan Young Park 《建筑学研究前沿(英文版)》2022,11(4):747-760
This study identifies the types of areas in Seoul where foreigners are concentrated by reflecting the characteristics of their region of origin and residence in Seoul. Lack of cultural understanding and uniform policies for various immigrant communities are causing some social issues. Hence, this study aims to prepare the basic data from which the government can predict changes in ethnic areas and prepare policies suitable for each derived type. The 14 most populous immigrant communities in Seoul were investigated, and cluster analysis and ANOVA test were performed. This examination resulted in four immigrant community types. Each type has specific characteristics, which have influenced the creation and change of the built environment. Types 1 and 4 are collectivistic. These types gradually tend to change urban environments to emulate the environment in their region of origin. In addition, they make little effort to improve their degraded environments, and such areas become increasingly backward. In contrast, types 2 and 3 are individualistic and prefer to assimilate into a migrant region. The formation and change of the urban environment for each type can be predicted on the basis of these characteristics. From this information, the government can prepare an appropriate urban architecture policy for each type. 相似文献
106.
Communities of practice are nowadays an important concept in the healthcare sector. Particularly, the intensive use of ICT has allowed their creation into a virtual environment – Virtual Communities of Practice (VCoPs) developing optimal conditions to make possible the collaborative learning process. The VCoPs antecedents can be situated on social network phenomenon, where individuals with different traits but a common interest/objective are linked, use ICT potency (especially social media) to interchange information, experiences and contents among them. And as a result, people create and share knowledge, and learn collaboratively. VCoP users have a higher satisfaction level in the collaborative learning process when they can: (1) Achieve benefits related to patient diagnosis and treatment (cost reductions, faster management, quality and accuracy of diagnosis, etc.); (2) Increase the share capital of participants and creating networks of trusted individuals. Given the interest in this topic, the objective of this work is to identify the factors that determine user satisfaction in relation to Community Practice (CoP) and the process of building shared knowledge. For this, a sample of 130 Spanish health professionals participating in an online community, and developed in a virtual community of practice, is discussed. The results obtained from an analysis of logistic regression show evidence of the perception of efficiency and effectiveness in collaboration with the members of the VCoP as positively influencing the perceived satisfaction with the CoP. Also, the degree of individual participation in the community affects the degree of perceived satisfaction. The conclusions provide interesting strategic recommendations in the management process of the CoP. 相似文献
107.
Over the past 20 years, the leaders of Israel's ultra-Orthodox (haredi) community carried out an intensive campaign against the diffusion of mobile phones in their enclave society. It included a variety of resistance strategies that escalated in parallel to the consistent increase in mobile phone penetration into the community. If at first the “cellphone danger” was contained by the successful “kosherphone,” a new threat appeared in the form of the smartphone. In this article we explore the severe rabbinic sanctions directed against those who deviate from the communal norm by using a smartphone. We analyze the general “lawfare” strategy of social distancing they adopted, and offer a close reading of the specific religious-law decrees, interpreting them through the historical and legal lens of halakhah (Jewish law). This socio-legal analysis constructs the way haredi leadership understands the role of the smartphone in two contexts. One is the rapidly changing contemporary media environment; the other is the social dynamic affecting this island community, as it encounters the surrounding national and global culture through digital media. The article concludes with a preliminary analysis of the implications of the Corona pandemic on the campaign against the smartphone. 相似文献
108.
Location plays a major role in the building of artistic, technological or scientific movements that emerge in specific locations before achieving a worldwide reach. However, a deeper understanding is needed about the interplay of local/global knowledge dynamics in the epistemic construction of a movement. Based on an in-depth longitudinal study of a critical case, this article sheds light on these issues by analysing the case of ‘techno-emotional cuisine’, a global gastronomic movement initiated and led by chef Ferran Adrià and his team at the restaurant elBulli in Catalonia (in Northern Spain). The results suggest that the dynamics of formation of a new epistemic movement depend on the form and nature of the interactions between the local buzz and global pipelines, and on the capacity of the originating community to develop and diffuse the new rules and ‘episteme’ on a global scale while consolidating them locally. 相似文献
109.
《Information & Management》2020,57(7):103245
Online knowledge-sharing communities typically acknowledge their top contributors by implementing recognition systems. Extant recognition systems suffer from several limitations such as treatment of the entire community as homogeneous and inflexibility of customization. We propose a framework based on socio-technical design principles for designing a multi-criterion- and multi-segment-based recognition system that exploits multiple user characteristics for differential recognition according to community goals. We apply this framework on data gathered from Yelp.com and show how it can be used to recognize top members of different identified behavioral segments (amateurs, adepts, and enthusiasts) based on their performance on various relevant factors. 相似文献
110.
Christopher Peacock-McLaughlin Peter S. Wlyudka Tammie M. Johnson Julie W. Merten 《Urban Research & Practice》2018,11(3):193-199
This preliminary study assesses the relationship between active transportation, the built environment, and population perceived health in two comparable cities in the Southeastern United States at different stages of improving infrastructure for active commuting. Behavioral Risk Factor Surveillance Survey data from 2006 to 2012 were analyzed for Charlotte, NC, and Jacksonville, FL. The annual difference between the percentage of Charlotte respondents rating physical health as good compared to Jacksonville’s increased at a rate of 13% based on an exponential growth regression model (p = 0.02). Supportive urban and transportation policies aimed at facilitating healthy behaviors are associated with healthier communities. 相似文献