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This paper explores technology upgrading of BRICS economies based on a three-pronged approach, which distinguishes between the intensity of technology upgrading, structural change and global interaction. We develop a statistical framework based on patent indicators to measure technological upgrading and apply it to BRICS economies in the period 1980–2015. The paper shows that there is no single path of technology upgrading. Instead, we find several unique paths with different trade-offs between intensity, structural change and the nature of the global interaction. All BRICS economies display increased generation of frontier technological activities, while China and Russia have also increased the intensity of behind frontier technological activities. China has also diversified its technology knowledge base and entered into dynamic frontier areas. With increasing intensity of frontier technology activities of the BRICS, the relative, but not absolute, the importance of foreign actors and international collaboration has declined. However, BRICS economies seem to lack the organisational and complementary capabilities to match the extent of technology sourcing from abroad, observed in high-income countries. Our result represents the application of a new conceptual framework and contributes to assessing the sustainability of innovation-based growth among BRICS.  相似文献   
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This research paper studies the Chinese technological system of production and innovation in the field of photovoltaics (PV). It contributes to a better understanding of the emergence and development of the system by utilizing three levels of analysis: the institutional framework of the system, the market dynamics of production and deployment, and the composition of innovation-related activities. The analysis demonstrates the interrelated roles of transnational factors, local government policies, and research and development (R&D) activities undertaken by the main actors in shaping the system dynamics. Tracking the relative position of China in the global PV manufacturing, installation and technological development, the analysis shows a gap between the growth of China’s market share and its modest share of transnational patent applications. This suggests a puzzle, which the paper attempts to answer by inspecting the individual companies in the system against four aspects. First, the dynamic development of their size and performance. Second, the nature of their international involvement through foreign direct investment and mergers and acquisition deals. Third, their technological specialization within the PV value chain over time. Fourth, the spatial scope of their patenting protection endeavours. The analysis recognises four periods of system development driven jointly by market dynamics and government plans. Behind the continuous growth of the system, there were different driving and moderating factors in each period.  相似文献   
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There is speculation about madaris in Pakistan as sources of terrorists and about levels and reasons for enrolment, but a dearth of empirical data. We studied madarsah enrolment among 53,960 representative households; 853 focus groups of parents discussed enrolment choices. In 2004, 2.6% of all children (3.8% of school-going children) aged 5–9 years attended a madarsah. Children from urban and less educated households were more likely to attend a madarsah, but there was no difference by sex of the child or household vulnerability. Parents chose madaris because they offered an Islamic education. Our findings challenge misconceptions about madaris in Pakistan.  相似文献   
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Abstract

This article discusses strategies used by Arab principals and teachers in Israel to cope with dilemmas involved in education for national identity stemming from conflict between two national narratives. While the Israeli Ministry of Education expects the Arab education system to educate students according to the Jewish State’s values, Palestinian Arab society expects its schools to educate its children according to Palestinian Arab national-cultural values. A qualitative research employed a semi-structured interview to elicit views on this issue from 7 principals and 14 teachers in the Arab education system in Israel. The findings indicate a conflictual reality. Interviewees expressed fear, humiliation and affront when required to obey Ministry of Education instructions in contradiction to attitudes prevalent in their society. They therefore developed coping strategies to foster students’ national identity without disrupting the necessary balance; primarily the construction of a covert learning program through manipulations in the official overt learning program. This study contributes to our understanding of minority education in a reality of conflict between the state and its national minority.  相似文献   
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The optimal operation conditions in an anoxic sulfide oxidizing (ASO) bioreactor were investigated. The maximal removal rates for sulfide and nitrate were found to be 4.18 kg/(m3·d) and 1.73 kg/(m3·d), respectively. The volumetrical volumetric loading rates (LRs) observed through decreasing hydraulic retention time (HRT) at fixed substrate concentration are higher than those by increasing substrate concentration at fixed HRT. The sulfide oxidation in ASO reactor was partially producing both sulfate and sulfur; but the amount of sulfate produced was approximately one third that of sulfur. The process was able to tolerate high sulfide concentration, as the sulfide removal percentage always remained near 99% when influent concentration was up to 580 mg/L. It tolerated relatively lower nitrate concentration because the removal percentage dropped to 85% when influent con- centration was increased above 110 mg/L. The process can tolerate shorter HRT but careful operation is needed. Nitrate conversion was more sensitive to HRT than sulfide conversion since the process performance deteriorated abruptly when HRT was decreased from 3.12 h to 2.88 h. In order to avoid nitrite accumulation in the reactor, the influent sulfide and nitrate concentrations should be kept at 280 mg/L and 67.5 mg/L respectively. Present biotechnology is useful for removing sulfides from sewers and crude oil.  相似文献   
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ABSTRACT

The present study was conducted to assess distance learning students’ perceptions about location and physical set up of libraries, collections, resources, and services rendered at thirty-four regional campuses as well as main campus libraries network of Allama Iqbal Open University (AIOU) all over Pakistan. During the spring semester of 2007, a questionnaire was mailed to 250 randomly selected students enrolled in eleven postgraduate programs throughout the country. The response rate was 61.2%, which was made up of 43.1% females and 56.9% males. A majority of the respondents were dissatisfied with the virtual reference services, online database facilities, interlibrary loan, library membership, and borrowing of library material from the AIOU libraries. They were satisfied with the location and physical setup of the libraries, the collections, and the resources of the libraries. The study revealed that most of the respondents used the libraries during workshops as well as for research purposes. The statistical analysis (t = 0.550, Sig. = 0.970) showed that there was no significant difference between the opinion of females and males. The data were analyzed using Statistical Package for Social Sciences (SPSS) for Windows version 10.0.  相似文献   
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Chickpea is an important food legume crop of Turkey and is largely grown for human consumption on low moisture or salt-affected soils.The objective of the study was to find the effects of NaCl stress at electrical conductivities of 4.5,8.6,12.7 and 16.3 dS/m and seed sizes (7,8 and 9 mm) on germination and early seedling growth of three popular chickpea cultivars (AKN-97,Gokce and Uzunlu-99).Mean frequency of germination,germination time,germination index,root length,shoot length and seedling fresh weight showed seed size-dependent responses of cultivars to salt stress.In general,small seeds germinated and grew more rapidly compared to medium and large seeds of the same cultivars against all levels of salt stress,with the best results in cultivar Uzunlu-99.No effect of NaCl treatments was observed on frequency of germination; however,a drastic decrease in early seedling growth was recorded at increased NaCl concentrations.Regression analysis results showed a significantly positive rela-tionship (P<0.01) between seed size and mean germination time,whereas a significantly negative relationship was recorded between seed size and germination index,root length,shoot length.Moreover,linear regression values apparently confirmed that increased seed size in each cultivar affected decreased germination index,root and shoot lengths with enhanced mean germination time.Thus,it was concluded that the use of small seeds could considerably reduce the production costs of chickpea in salt-affected soils.  相似文献   
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