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Almerie MQ Matar HE Jones V Kumar A Wright J Wlostowska E Adams CE 《Health information and libraries journal》2007,24(4):283-286
Background: The Polish Medical Bibliography (Polska Bibliografia Lekarska) contains 350 000 records dating from 1979. These records from the fields of medicine, nursing, dentistry, health care systems and preclinical sciences are from nearly 300 biomedical journals published in Poland. Methods: We systematically searched the Polish Medical Bibliography Part II (1996–2006) CD‐ROM (July 2006) using both English and Polish phrases for randomized trials, manually checked results and, for the trials identified in this way, sought these on medline and embase . Results: Systematic searching identified records of 680 randomized trials from all areas of health care. Nearly 40% of these were not found on either medline or embase . Conclusions: The Polish Medical Bibliography should be of interest to health care information specialists concerned with comprehensive searches for trials. 相似文献
263.
Disturbance rejection in nonlinear uncertain systems is a challenging issue especially when the sensor noise cannot be eliminated by low pass filtering. Fuzzy relational models (FRM) can effectively represent the sensor noise in the fuzzy control signal. Due to the large amount of sensor noise there will be huge actuator movement. In most of the cases the actuator movement is in response to the noise and not due to the set-point change. Conditional defuzzification is employed to reduce the control activity. The amount of control activity depends on the threshold level of the conditional defuzzification scheme. A novel scheme has been presented in this paper which can significantly reduce the actuator movement due to noise by adapting the conditional defuzzification threshold. Effective disturbance rejection can be achieved if the controller is modeled as an exact inverse of the plant model. The controller is a fuzzy relational model which develops the inverse plant model by incorporating feedback error learning. Sensitivity analyses have been carried out which demonstrate the efficiency of the proposed methodology. 相似文献
264.
Ikram-ul- Haq Asif Ali Khan Iqrar Ahmad Khan Muhammad Abubakkar Azmat 《Journal of Zhejiang University. Science. B》2012,13(7):533-544
The okra germplasm was screened for salinity tolerance at the seedling stage and during plant ontogeny. Substantial variation existed in okra for salinity tolerance at the seedling stage. An 80 mmol/L NaCl concentration was suitable for discriminating tolerant and non-tolerant okra genotypes. The pooled ranking of the genotypes, based on individual rankings for each trait (root and shoot length, germination percentage, and relative Na+ and K+) in individual NaCl concentrations, was effective for selecting tolerant genotypes. Genotypes selected at the seedling stage maintained their tolerance to NaCl during plant ontogeny, suggesting that screening of the germplasm entries and advanced breeding materials for salt tolerance at the seedling stage is effective. Among 39 okra genotypes, five were identified as the most tolerant genotypes and showed potential for use in breeding programs that focus on the development of salt-tolerant, high-yield okra cultivars. 相似文献
265.
Masoud Kabiri Mahmood Ghazi-Tabatabaei Abbas Bazargan Mohsen Shokoohi-Yekta Kamal Kharrazi 《教育实用测度》2017,30(1):27-38
Numerous diagnostic studies have been conducted on large-scale assessments to illustrate the students’ mastery profile in the areas of math and reading; however, for science a limited number of investigations are reported. This study investigated Iranian eighth graders’ competency mastery of science and examined the utility of the General Diagnostic Model (GDM) to produce diagnostic information using TIMSS 2011 data. Eight diagnostic attributes were extracted, using documentary analysis of the major large-scale assessment frameworks, including basic science knowledge, using models, reasoning, using science, representing data, explaining of phenomena, predicting, and scientific inquiry. These attributes were then assigned to each item in order to construct the Q matrix, through focus group discussions, survey of head science teachers, think-aloud verbal protocol, and analysis of written answers. Results show the utility of GDM to generate rich diagnostic information for a national large-scale assessment. Moreover, the findings indicated that students performed relatively well in using science, but performed weakly in reasoning, explaining of phenomena, and scientific inquiry, which all required complex skills and higher-order thinking abilities. 相似文献
266.
Muhammad M. Abdel Latif 《Journal of Research in Reading》2015,38(2):194-212
High levels of apprehension cause students to have writing difficulties. This study attempted to identify the sources of Egyptian university students’ English writing apprehension. The study made use of both quantitative and qualitative data. The scores of 57 students on a writing apprehension scale were compared to their scores on another scale assessing writing self‐efficacy and three linguistic tests measuring English grammar and vocabulary. Additionally, 15 apprehensive students and 16 nonapprehensive students were interviewed about their writing experiences and beliefs. Analysis of the quantitative and qualitative data showed that there are six sources of the students’ English writing apprehension: linguistic knowledge level, perceived language competence, writing performance level, perceived writing competence, instructional practices and fear of criticism. These results indicate the integrative nature of L2 writing ability and emphasise the need for dealing with these sources of apprehension. The study recommends that reducing L2 students’ writing apprehension should start by improving their linguistic knowledge and writing ability; this will result in bringing about a positive change in their language and writing competence self‐perceived beliefs. In addition, the study presents some other recommendations for improving instructional practices of English writing in the Egyptian context. 相似文献
267.