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121.
The present drinking water purification system in Egypt Uses surface water as a raw water supply without a pre-liminary filtration process.On the other hand,chlorine gas iS added as a disinfectant agent in two steps,pre- and post.chlorination.Due to these reasons most of water treatment plants suffer low fltering effectiveness and produce the trihalomethane (THM) species as a chlorination by-product.The Ismailia Canal represents the most distal downstream of the main Nile Rivet.ThUS its water contains all the proceeded pollutants discharged into the Nile.In addition.the downstream reaches of the canal act as an agricultural drain during the closing period of the High Dam gates in January and February every year.Moreover,the wide in-dustrial zone along the upstream course of the carlal enriches the canal water with high concentrations of heavy metals.The obtained results indicate that the canal gains up to 24.06×106m3 of water from the surrounding shallow aquifer during the closing period ofthe High Dam gates,while during the rest ofthe year,the callal acts as an influent stream losing about 99.6×106m3 of its water budget.The reduction oftotaI organic carbon(TOC) and suspended particulate mattes(SPMs)should be one of the central goals of any treatment plan to avoid the disinfectants by-products.The combination of sedimentation basins.gravel pre-filtration and slow sand filtration,and underground passage with microbiological oxidation-reduction and adsorption criteria showed good removal of parasites and bacteria and complete elimination of TOC.SPM and heavy metals.Moreover,it reduces the use of disinfectants chemicals and lowers the treatment costs.However,this purification system under the arid climate prevailing in Egypt should be tested and modified prior to application.  相似文献   
122.
The analysis of circular concrete columns using unconfined concrete models is a well established practice. However, there is a necessity to develop realistic analysis and design tools that predict the extreme ultimate capacity of such columns since modern codes and standards like AASHTO LRFD are introducing extreme load events. The increase in strength and ductility due to full axial confinement is not applicable to pure bending and bending plus axial load simply because the area of effective confined concrete is reduced. The higher the eccentricity the smaller the compressed portion of the confined core. Accordingly, the ultimate confined strength is gradually reduced from the fully confined value fcc′ (at zero eccentricity) to the unconfined value fc (at infinite eccentricity) as a function of eccentricity to diameter ratio. A numerical analysis algorithm is developed using the finite layer procedure and the secant stiffness approach within a framework of incremental-iterative moment of area computations. The resulting nonlinear section analysis requires radial loading in which the eccentricity is kept constant or the axial load is proportional to the applied moment. The results are compared with existing experimental data and the widely used Mander model to benchmark the present predictions.  相似文献   
123.
Abstract

The main aim of this paper is to empirically examine the information skills of public university librarians and whether attending a short training on navigation to e-resources results in improvements in their knowledge base. A group of 33 librarians working at different public university libraries participated in this study. They were participants in a 90-min long training program on navigation to e-resources conducted at University Grants Commission of Bangladesh. The survey questionnaire, consisted of 12 information tasks, was distributed and answered before the training. The same tasks were repeated at the end of the training session to see the improvement of information skills. It was found that librarians did not have adequate knowledge of information skills; in fact, a major proportion of university librarians demonstrated inappropriate and insufficient knowledge before the training. The training helped improve their performance score significantly in six out of 12 tasks. The study concluded that the provision of systematic and regular training will improve the skills of librarians and it will positively affect their service outcomes.  相似文献   
124.
This study investigated the spatial analysis of tactile hierarchical patterns in 110 early‐blind children aged 6–8 to 16–18 years, as compared to 90 blindfolded sighted children, in a naming and haptic drawing task. The results revealed that regardless of visual status, young children predominantly produced local responses in both tasks, whereas the production of integrated responses emerged later. Development of local and global processing seems to proceed similarly in the two populations, but local processing continued to occur at high levels over a larger age range in the blind. The possibility of visual mediation is pointed out, as totally blind children tended to process information locally more often than blind children with minimal light perception.  相似文献   
125.
Fieldwork training is a key component of several practical disciplines. In this study, students’ peer assessment of fieldwork is explored as a method to improve their practical training. Peer assessment theories are first discussed. A framework for peer assessment of fieldwork is proposed, and the steps taken for preparation of students for this task are discussed. A developed marking, feedback and moderation tool of assessment are presented. Application of peer assessment in the field was investigated over a period of two years in one undergraduate unit in the geospatial discipline as an example. Reliability of peer assessment was estimated by measuring the difference between assessments carried out by groups of peer assessors, and its validity was measured by comparing students’ marks with those given by tutors. Results show that students have gained from the peer assessment process, mainly as a formative form of assessment, by better understanding and endeavouring to achieve the objectives of field tasks. Tutors use differences among assessments made by groups of students compared to tutors’ assessments to identify field components that need better explanation of their content and assessment criteria.  相似文献   
126.
This paper deals with the problem of stabilization by state feedback control of Takagi–Sugeno (T–S) fuzzy discrete-time systems with multiple fixed delays while imposing positivity in closed-loop. The obtained results are presented under linear programming (LP) form. In particular, the synthesis of state feedback controllers is first solved in terms of Linear programming for the unbounded controls case. This result is then extended to the stabilization problem by nonnegative controls, and stabilization by bounded controls. The stabilization conditions are derived using the single Lyapunov–Krasovskii functional (LKF). An example of a real plant is studied to show the advantages of the design procedure. A comparison between linear programming and LMI approaches is presented.  相似文献   
127.
Needs assessment is the process of identifying the gap between a target population's needs and its services. If a gap exists, a program can be designed to effectively respond to those needs. This aticle explores the needs of elderly African immigrants in Minnesota through the use of qualitative interviews. A convenience sampling was used to collect data from 200 available elderly people in eight cities in Minnesota. Data analyses revealed that 90% of them want appropriate nutrition and better delivery of services. Recommendations include support for informal caregivers like family members becuase these efforts can keep older people at home.  相似文献   
128.
While debate about the use of—and alternatives to—human cadaveric dissection in medical training is robust, little attention has been paid to questions about timing. This study explores the perspectives of medical students and recent graduates with regard to two key questions: when in the degree program do students prefer dissection opportunities and what are the students getting out of participating in dissection? Self-report survey data from students in preclinical years (n = 105), clinical years (n = 57), and graduates (n = 13) were analyzed. Most (89%) preferred dissection during the preclinical years, with no effect by training year (χ2 = 1.98, p = 0.16), previous anatomy (χ2 = 3.64, p = 0.31), or dissection (χ2 = 3.84, p = 0.26) experience. Three key findings emerged. First, the majority of students prefer to dissect in the preclinical years because they view dissection as important for developing foundation knowledge and delivering an opportunity for consolidation prior to transitioning to primarily clinical studies. In addition, students recognize that it is a time-consuming activity requiring specialized facilities. Second, three main understandings of the purpose of dissection were reported: depth of learning, learning experience, and real-world equivalence. Third, these student perspectives of the purpose of dissection are associated with timing preferences for dissection opportunities. The results identify the preclinical phase as the optimal time to strategically integrate dissection into medical training in order to maximize the benefits of this unique learning opportunity for students and minimize its impact upon curricular time.  相似文献   
129.
We examined the effectiveness of a researcher‐provided reading intervention with 484 fourth graders with significant reading difficulties. Students were randomly assigned to one year of intervention, two years of intervention, or a business‐as‐usual comparison condition (BAU). Students assigned to two years of intervention demonstrated significantly greater gains in reading fluency compared to students who received one year of intervention and the BAU group. Students in both the one‐ and two‐year groups demonstrated similar and significantly larger gains in word reading in comparison to the BAU group. There were no statistically significant differences between the three groups on standardized measures of reading comprehension. We discuss these results in the context of research with late elementary and secondary students targeting reading comprehension.  相似文献   
130.
This paper presents our work towards developing a new speech corpus for Modern Standard Arabic (MSA), which can be used for implementing and evaluating Arabic speaker-independent, large vocabulary, automatic, and continuous speech recognition systems. The speech corpus was recorded by 40 (20 male and 20 female) Arabic native speakers from 11 countries representing three major regions (Levant, Gulf, and Africa). Three development phases were conducted based on the size of training data, Gaussian mixture distributions, and tied states (senones). Based on our third development phase using 11 hours of training speech data, the acoustic model is composed of 16 Gaussian mixture distributions and the state distributions tied to 300 senones. Using three different data sets, the third development phase obtained 94.32% and 8.10% average word recognition correctness rate and average Word Error Rate (WER), respectively, for same speakers with different sentences (testing sentences). For different speakers with same sentences (training sentences), this work obtained 98.10% and 2.67% average word recognition correctness rate and average WER, respectively, whereas for different speakers with different sentences (testing sentences) this work obtained 93.73% and 8.75% average word recognition correctness rate and average WER, respectively.  相似文献   
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