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521.
E. Z. Suluimanov V. A. Frolova S. K. Khasenova 《Scientific and Technical Information Processing》2009,36(5):290-297
This paper gives the results of the scientometric analysis of foreign publications by Kazakh authors that was reflected in
the SCOPUS DB in 1991–2008. The publication activity is expressed in 3883 documents, the citation index of which is 10 132.
The average share of Kazakh publications in the total worldwide flow is equal to 0.017%. The citation rate of publications
was revealed to have significantly grown since the 1996–2000 period. It is shown that most articles were written in English
and published in periodical editions. The main themes of publications are represented by physics and chemistry. The leading
foreign partners of Kazakhstan in the scientific sphere were determined. Kazakh-Russian scientific cooperation is developing
most fruitfully. 相似文献
522.
Hanaa B. Atya Sahar A. Ali Mohamed I. Hegazy Fathia Z. El Sharkawi 《Indian journal of clinical biochemistry : IJCB》2018,33(2):163-170
Urine is a proven source of metabolite biomarkers and has the potential to be a rapid, noninvasive, inexpensive, and efficient diagnostic tool for various human diseases. Despite these advantages, urine is an under-investigated source of biomarkers for multiple sclerosis (MS). The objective was to investigate the level of some urinary metabolites (urea, uric acid and hippuric acid) in patients with MS and correlate their levels to the severity of the disease, MS subtypes and MS treatment. The urine samples were collected from 73 MS patients-48 with RRMS and 25 with SPMS- and age matched 75 healthy controls. The values of urinary urea, uric acid and hippuric acid in MS patients were significantly decreased, and these metabolites in SPMS pattern showed significantly decrease than RRMS pattern. Also showed significant inverse correlation with expanded disability status scale and number of relapses. Accordingly, they may act as a potential urinary biomarkers for MS, and correlate to disease progression. 相似文献
523.
Torstein E. Dæhlin Tron Krosshaug Loren Z. F. Chiu 《Journal of sports sciences》2018,36(19):2242-2249
The purpose of this research was to investigate how lower extremity work was distributed during the pull of cleans performed lifting the barbell to the minimum height required to receive it in a full squat (minimal height clean); or with maximum effort to elevate the barbell as high as possible and receiving it in either a full (maximal effort clean) or partial (power clean) squat. Eight weightlifters screened for proficient technique performed these clean variations at 80% of one repetition maximum. Work performed on the barbell and by the lower extremity net joint moments (NJM) was computed from marker trajectories and ground reaction forces. Total barbell work, lower extremity NJM work, knee extensor work, and knee joint excursion during the second pull was lower in the minimal height clean than the maximal effort and power cleans (P < 0.05). This research demonstrates that more knee extensor work is performed in the second pull of maximal effort and power cleans compared to the minimal height clean. The larger knee extensor work performed is due to larger knee joint excursion during the second pull of the maximal effort and power cleans, but not larger knee extensor NJM. 相似文献
524.
This paper studies the load mitigation problem for wind turbines by using active tuned mass dampers. A state space model for the tower/nacelle system is established with the consideration of tower/blade interaction. The uncertainties that appear in the damping matrix and natural frequencies are also considered in the controller design. External loads acting on the tower including the drag force induced by winds and the absolute base shear induced by the rotating blades are involved, and shaping filters for online generating these loads are proposed which can be easily implemented in numerical simulations. An adaptive sliding-mode controller is proposed to handle the system uncertainties, external disturbances and hard constraint, and also to improve the overall performance of the wind turbine system. Numerical simulations are performed to demonstrate the effectiveness of the proposed control law. 相似文献
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The author presents a review of some mathematical aspects of magnetohydrodynamics and plasma-dynamics, and the fields of mathematics required and used in those domains are briefly discussed. The last section is devoted to the discussion of adjusting the mathematical program of a university, from the point of view of engineering, physics and mathematics, so that a greater number of students in those disciplines will be prepared for graduate courses in magnetohydrodynamics and plasma-dynamics. 相似文献
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