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Effectiveness and time-course adaptation of resistance training vs. plyometric training in prepubertal soccer players

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Journal of sport and Health science 2020年第6期9卷 620-627页

作者： Yassine Negra Helmi Chaabene Thomas stöggl Mehréz Hammami Mohamed souhaiel Chelly younés Hachana Research Unit“sport Performance Health&Society”Higher Institute of Sport and Physical Education of Ksar SaidTunis 2009Tunisia Tunisian Research Laboratory“sports Performance Optimization” National Center of Medicine and Science in Sports(CNMSS)Tunis 1003Tunisia Department of sport science and Kinesiology University of SalzburgSalzburg 5400Austria Higher Institute of sports and Physical Education Manouba UniversityTunis 2009Tunisia

Purpose:This study aimed to assess the effectiveness and time course for improvements in explosive actions through resistance training(RT)*** training(PT)in prepubertal soccer ***:Thirty-four male subjects were assigned to:a control group(n=11);an RT group(5 regular soccer training sessions per week,n=12);a PT group(3 soccer training sessions and 2 RT sessions per week,n=11).The outcome measures included tests for the assessment of muscle strength(e.g.,1 repetition maximum half-squat test),jump ability(e.g.,countermovement jump,squat jump,standing long jump,and multiple 5 bounds test),linear speed(e.g.,20m sprint test),and change of direction(e.g.,Illinois change of direction test).Results:The RTG showed an improvement in the half-squat(△=13.2%;d=1.3,pweek 4,whereas improvements in the 20-m sprint(△=4.2%;d=1.1,ps(△=5.1%;d=1.5,pstanding long jump(△=7.2%;d=1.2,psquat jump(△=19.6%;d=1.5,pwere evident at week *** PTG showed improvements in CoD(△=2.1%;d=1.3,pstanding long jump(△=9.3%;d=1.1,psquat jump(△=16.7%;d=1.4,pweek 8 whereas improvements in the 20-m sprint(△=4.1%;d=1.3,ps(△=7.4%;d=2.4,pwere evident only after *** RT and PT groups showed improvements in all sprint,CoD,and jump tests(psquat performance,for which improvement was only shown within the RTG(psion:RT and PT conducted in combination with regular soccer training are safe and feasible interventions for prepubertal soccer *** addition,these interventions were shown to be effective training tools to improve explosive actions with different time courses of improvements,which manifested earlier in the RTG than in the *** outcomes may help coaches and fitness trainers set out clear and concise

关键词： Change of direction Jump performances Plyometric training Resistance training soccer Time course

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Effects of fracture distribution and length scale on the equivalent continuum elastic compliance of fractured rock masses

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第6期7卷 626-637页

作者： Marte Gutierrez Dong-Joon youn Department of Civil and Environmental Engineering Colorado School of Mines Department of Civil Infrastructure and Environmental Engineering Khalifa University

Fracture systems have strong influence on the overall mechanical behavior of fractured rock masses dueto their relatively lower stiffness and shear strength than those of the rock matrix. Understanding theeffects of fracture geometrical distribution, such as length, spacing, persistence and orientation, isimportant for quantifying the mechanical behavior of fractured rock masses. The relation betweenfracture geometry and the mechanical characteristics of the fractured rock mass is complicated due tothe fact that the fracture geometry and mechanical behaviors of fractured rock mass are stronglydependent on the length scale. In this paper, a comprehensive study was conducted to determine theeffects of fracture distribution on the equivalent continuum elastic compliance of fractured rock massesover a wide range of fracture lengths. To account for the stochastic nature of fracture distributions, threedifferent simulation techniques involving Oda＇s elastic compliance tensor, Monte Carlo simulation （MCs）,and suitable probability density functions （PDFs） were employed to represent the elastic compliance offractured rock masses. To yield geologically realistic results, parameters for defining fracture distributionswere obtained from different geological fields. The influence of the key fracture parameters andtheir relations to the overall elastic behavior of the fractured rock mass were studied and discussed. Adetailed study was also carried out to investigate the validity of the use of a representative elementvolume （REV） in the equivalent continuum representation of fractured rock masses. A criterion was alsoproposed to determine the appropriate REV given the fracture distribution of the rock mass.

关键词： Fractured rock mass Equivalent continuum elastic compliance Monte Carlo simulation(MCs) Representative element volume(REV) scale effects

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Improvement of light uniformity by lighting arrangement for standardized crop production

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Journal of Central south University 2014年第11期21卷 4311-4319页

作者： Lee Hwa-soo Kwon sook-youn Lim Jae-Hyun Department of Computer science and Engineering Kongju National UniversityCheonan 331-717 Korea

In a commercialized, fully artificial plant factory, artificial luminaire is arranged in a unified way using a general illumination theory, an actual measurement, or an empirical methodology. However, with these methods, lightings are implemented without considering specific optical characteristics of lighting or material characteristics of each component that constructs a cultivation system, resulting in an amount of light that becomes irregular. The amount of lighting is closely related with the growth and quality of crops, and the deviation between points where cultivated crops are located causes quality difference in the produced crops, thus impairing the economic feasibility of a plant factory. In this regard, a simulation to figure out an optimum lighting layout was performed. Arrangements based on the spectrum distribution of light source and reflector materials were implemented to ascertain the distance between lighting and height of lighting and gather information in the pre-treatment process to improve the uniformity of light in the plant cultivation system. Improvement of around 15% in light uniformity is achieved compared with the existing system after the simulation is carried out. This result would reduce the deviation in crop growth to make uniform quality crop production possible.

关键词：照明布置作物生产均匀度植物工厂栽培系统材料特性作物生长经济可行性

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Effect of Palladium Nanoparticles on Photocatalytic Characteristics of N doped Titania Catalyst

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Journal of Materials science & Technology 2015年第6期31卷 664-669页

作者： Jong-Ho Lee Jeong-Il youn young-Jig Kim Han-Jun Oh Department of Chemistry Hanseo University school of Advanced Materials Engineering Sungkyunkwan University Department of Materials science Hanseo University

To improve the photocatalytic efficiency of TiO2nanotubular catalyst,N doped and Pd decorated titania nanotubes was successfully synthesized via anodizing,hydrazine hydrate treatment and photoreduction of Pd *** small Pd nanoparticles were precipitated on TiO2nanotubes through photoreduction of Pd ions,and its distribution is relatively *** X-ray photoelectron spectrometry（XPs） result,the N 1s spectrum represents two peaks with binding energy at 399.7 and 400.7 eV,which suggests that the nitrogen elements doped by hydrazine hydrate treatment are located in interstitial sites of the TiO2crystalline *** N doped TiO2nanotubes with Pd particles,a high photocurrent was detected due to increase of interface charge carrier separation ***,N doped and Pd decorated TiO2nanotubes exhibited much higher dye destruction efficiency and rate constant due to the synergistic effect of the N dopant and the Pd deposition on TiO2nanotubes.

关键词： Pd nanoparticle Titania nanotube Anodizing Dye dec

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Cavernous mesenteric lymphangiomatosis mimicking metastasis in a patient with rectal cancer:A case report

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world Journal of Gastroenterology 2009年第31期15卷 3947-3949页

作者： seong su Hwang Hyun Joo Choi soo youn Park Department of Radiology St.Vincent's HospitalCollege of MedicineThe Catholic University of Korea Department of Pathology St.Vincent's HospitalCollege of MedicineThe Catholic University of Korea

Lymphangioma usually occurs in children and usually involves the skin. Mesenteric lymphangioma is extremely rare in adults. Typically, lymphangioma appears on computed tomography (CT) as a lower attenuation of a cystic mass, however, some cases appear to be a solid mass. we describe the CT and 18F-FDG positron emission tomography/CT appearance in a case of jejunal and mesenteric cavernous lymphangi-omatosis mimicking metastasis in an adult patient with rectal cancer.

关键词：淋巴管瘤肠系膜直肠癌海绵状病例报告模仿计算机断层扫描患者

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Obesity promotes oxidative stress and exacerbates blood-brain barrier disruption after high-intensity exercise

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Journal of sport and Health science 2017年第2期6卷 225-230页

作者： Hee-Tae Roh su-youn Cho wi-young so Department of Physical Education Dong-A University Busan 604-714 Republic of Korea school of Taekwondo College of Creative Human ResourcesYoungsan UniversityYangsan-si 626-790Republic of Korea sports and Health Care Major College of Humanities and ArtsKorea National University of TransportationChungju-si 380-702Republic of Korea

Purpose: The purpose of this study was to investigate the effects of obesity and high-intensity acute exercise on oxidant-antioxidant status,neurotrophic factor expression, and blood-brain barrier(BBB) ***: Twenty-four healthy, untrained men(12 non-obese(mean 14.9% body fat) and 12 obese subjects(mean 29.8% body fat)) performed20 min of continuous submaximal aerobic exercise at 85% maximal oxygen consumption. Blood sampling was performed to examine the oxidant-antioxidant status(reactive oxygen species(ROs) and superoxide dismutase(sOD)), neurotrophic factors(brain-derived neurotrophic factor(BDNF) and nerve growth factor(NGF)), and BBB disruption(s100β and neuron-specific enolase) before and after acute ***: The obese group showed significantly higher pre-exercise serum ROs levels and significantly lower pre-exercise serum sOD levels than the non-obese group(p serum ROs, sOD, BDNF, NGF, and s100β levels were significantly increased post-exercise compared with pre-exercise levels in both the non-obese and the obese groups(p se group showed significantly higher serum ROs, BDNF, NGF,and s100β levels post-exercise compared to the non-obese group(p sion: Our study suggests that episodic vigorous exercise can increase oxidative stress and blood neurotrophic factor levels and induce disruption of the BBB. Moreover, high levels of neurotrophic factor in the blood after exercise in the obese group may be due to BBB disruption,and it is assumed that oxidative stress was the main cause of this BBB disruption.

关键词：水平运动血脑屏障氧化应激高强度脑源性神经营养因子肥胖神经元特异性烯醇化酶超氧化物歧化酶

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Clay minerals and geochemistry of the bottom sediments in the northwestern East China sea

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Chinese Journal of Oceanology and Limnology 2007年第3期25卷 235-246页

作者： Jeungsu youn shouye YANG Yong Ahn PARK Department of Oceanography College of Ocean Sciences Cheju National University Jeju-do 690-756 Korea state Key Laboratory of Marine Geology Tongji University Research Institute of Oceanography Seoul National University Seoul 151-742 Korea

Clay minerals of 34 sediments collected from the northwestern continental shelf of the East China sea have been determined by X-ray diffraction analysis. The clay mineral distribution is mainly controlled by the sediment source and the dominant circulation pattern. The predominant clay mineral in our study area is illite comprising more than 67% of the whole clay fraction. The highest concentration of illite (>68%) is found in the southeastern offshore parts beyond the reach of terrigenous input from the Jeju Island. It means that these illites are largely transported by the Kuroshio Current from the south China sea (sCs). smectite is highly concentrated in the northwest middle part and in the outer-shelf mud patch. It seems to be due to the high supply of smectite transported from China where fine-grained sediments are discharged from modern and ancient Huanghe (Yellow) River. The relatively high abundant kaolinite is likely derived from the Changjiang (Yangtze) River via the Taiwan warm Current. In contrast, large amounts of chlorite and high chlorite/kaolinite ratios occur in the northwestern area, reflecting the transportation by the Yellow sea Coastal Current from the southern Yellow sea. The discrimination diagrams clearly show that the sediments in the northwestern East China sea are ultimately sourced from Chinese rivers, especially from the Huanghe River, whereas the sediment in the northeast part might come from the Jeju Island. The muddy sediments of the Changjiang River’s submerged delta have much lower 87sr/86sr ratios (0.716 2–0.718 0) than those of the shandong Peninsular mud wedge (0.721 6–0.724 9), which are supposed to be originated from the Huanghe River, suggesting the distribution pattern of 87sr/86sr ratios as a new tracer to discriminate the provenance of shelf sediments in the study area. The 87sr/86sr ratios of the outer-shelf muddy sediments ranged from 0.7169 to 0.7216 in a wide range and was between those of the Huanghe River and Changjia

关键词：粘土矿物地球化学锶同位素中国东海

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NUMERICAL ANALYsEs OF FLOw FIELDs IN A VANED DIFFUsER wITH VARIOUs FLOw RATEs

NUMERICAL ANALYSES OF FLOW FIELDS IN A VANED DIFFUSER WITH V...

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第一届亚洲制冷空调大会

作者： H.-s.Kim D.-w.Kim youn J.Kim school of Mechanical Engineering SungKyunKwan University 300 Cheoncheon-dong Suwon 400-746 Korea school of Mechanical Engineering SungKyunKwan University 300 Cheoncheon-dong Suwon 400-746 Korea school of Mechanical Engineering SungKyunKwan University 300 Cheoncheon-dong Suwon 400-746 Korea

＜正＞The optimal design of the elements, i.e., impeller, diffuser, and casing in a turbo-compressor is very important, because the dynamic energy developed by the impeller transformed into the pressure energy in the diffuser and casing. The performance characteristics of the diffuser are complicated with different geometric shapes. To improve the performance of the small-size turbo compressor with a high rotating speed, the effects of flow rates from 0.8 times design point to 1.2 times Qd are numerically studied. Also, the comparison of the performance of the vaneless and vaned diffusers carried out. A blade of an impeller has two-dimensional backswept shape to avoid the tip clearance effects. In order to predict the flow pattern inside the entire impeller, diffuser and casing, calculations with multiple frames of reference method between the rotating and stationery parts of the domain are carried out. All domains for analyses are discretized by bexahedral elements. Three-dimensional, unsteady, viscous governing equations are solved using FVM, sIMPLE algorithm, and κ-εturbulence model. The pressure recovery coefficient （Cp） and the loss coefficient （K） have been calculated to estimate the performance and loss of the diffuser. Furthermore, the magnitude of velocity and the distributions of static and total pressures are calculated along the length of the diffuser.

关键词： Turbo-compressor Vaned and vaneless diffusers Loss coefficient Pressure recovery coefficient

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Validation of sea Level Data in the East Asian Marginal seas: Comparison between TOPEX/POsEIDON Altimeter and In-situ Tide Gauges

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Advances in Atmospheric sciences 2003年第4期20卷 650-660页

作者： Yong-Hoon youn Im sang OH Ki-Hyun KIM young-Hyang PARK Jong woo KIM Meteorological Research Institute/Korea Meteorological Administration SeoulKoreaResearch Institute of OceanographySeoul National UniversitySeoulKoreaDepartment of Earth SciencesSejing UniversitySeoulKoreaLaboratoire d'Oceanographie PhysiqueMuseum National d'Histoire NaturelleParisDepartment of Earth SciencesSejong UniversitySeoulKorea

In an effort to assess the reliability of satellite altimeter systems, the authors conduct a comparative analysis of sea level data that were collected from the TOPEX/POsEIDON (T/P) altimeter and 10 tide gauges (TG) near the satellite passing ground tracks. The analysis is made using datasets collected from marginal sea regions surrounding the Korean Peninsula at T/P cycles of 2 to 230, which correspond to October 1992 to December 1998. Proper treatment of tidal errors is a very critical step in data processing because the study area has very strong tide. when the T/P data are processed, the procedures of Park and Gamberoni (1995) are adapted to reduce errors associated with the tide. when the T/P data are processed in this way, the alias periods of M2, s2, and K1 constituents are found to be 62.1, 58.7, and 173 days repectively. The compatibility of the T/P and TG datasets are examined at various filtering periods. The results indicate that the low-frequency signals of the T/P data can be interpreted more safely with longer filtering periods (such as up to the maximum selected value of 200 days). when RMs errors for the 200-day low-pass filter period are compared with all 10 tidal stations, the values span the range of 2.8 to 6.7 cm. The results of a correlation analysis for this filtering period also show a strong agreement between the T/P and TG datasets across all stations investigated (e.g.,p- values consistently less than 0.001). Hence according to the analysis, the conclusion is made that the analysis of surface sea level using satellite altimeter data can be made safely with reasonably extended filtering periods such as 200 days.

关键词： sea level TOPEX/POsEIDON altimeter tide gauge

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Influence of volcanic activity on vegetation succession and growth environment on the hillslope of sakurajima Volcano in southern Kyushu,Japan

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Journal of Forestry Research 2017年第2期28卷 309-317页

作者： Yukiyoshi Teramoto Etsuro shimokawa Tsugio Ezaki Kun-woo Chun suk-woo Kim youn-Tae Lee Faculty of Agriculture Kagoshima UniversityKagoshima 890-0065Japan Faculty of Agriculture Ehime UniversityMatsuyama 790-8566Japan Division of Forest science Kangwon National UniversityChuncheon 24341Republic of Korea Department of Forestry and Environmental systems Graduate SchoolKangwon National UniversityChuncheon 24341Republic of Korea

This study was conducted in order to examine the influence of long-term volcanic activity on vegetative succession and growth on the slope of sakurajima in southern Kyushu, Japan. we investigated the vegetation,depth of the volcanic ash layer, and dry density and p H of the surface soil at six places on the north-northwestern slope, 2.3–3.4 km from the Minami-dake crater, where a layer of pumice stone was deposited by the Taisho eruption in 1914. The height and diameter at breast height（DBH） of the trees increased with increasing distance from the Minami-dake crater, as did the number of individuals and species, and basal area. The shannon–wiener diversity index（H＇） demonstrates that vegetative succession is significantly affected by distance from the Minami-dake crater, as areas farther from the crater exhibited later seral stages. Comparison of the diversity index and species number of the crater region with that of the climax forest in Kagoshima indicates that vegetative growth alone cannot advance succession in the study area, as the local vegetative community is heavily influenced by the harsh environmental conditions associated with continual exposure to long-term volcanic activity. seral stage, ash layer depth,dry density, and p H of the soil surface layer are governed by distance from the Minami-dake crater. The results of this study indicate that conditions for vegetative growth and succession improve with increasing distance from the source of constant volcanic activity. Thus, soil development is promoted by the acidification of the soil, which decreases the dry density and p H of the soil surface *** introduction of plant species resistant to volcanic ash and gas is recommended to promote soil development and improve the infiltration capacity of the soil.

关键词： volcanic succession vegetation vegetative northwestern eruption basal leaved gentle harsh

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