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Applications of numerical optimization techniques to design of axial compressor blades

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航空动力学报 2007年第4期22卷 645-652页

作者： Choon-Man Jang kwang-yong Kim Fire and Engineering Services Research Department KICT Department of Mechanical Engineering Inha University

This paper describes the shape optimization of NASA rotor 37 and rotor and stator blades in a single-stage transonic axial *** optimization of the blades operating at the design flow condition has been performed using the response surface method and three-dimensional Navier-Stokes ***-layer approximation is introduced to the Navier-Stokes equations,and an explicit Runge-Kutta scheme is used to solve the governing *** three design variables,blade sweep,lean and skew,are introduced to optimize the three-dimensional stacking line of the *** objective function of the shape optimization is an adiabatic *** the optimization of rotor and stator blades, optimal blade shape can be *** is noted the increase of adiabatic efficiency by optimization of the blade shape with the stacking line in the single-stage transonic axial compressor is more effective in a rotor blade rather than a stator blade because of the large deformation of blade shape in the stator blade.

关键词：轴挤压叶片机航空推进系统最优化倾斜

Designing a Biomimetic Ornithopter Capable of Sustained and Controlled Flight

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Journal of Bionic Engineering 2008年第1期5卷 39-47页

作者： Joon Hyuk park kwang-Joon Yoon Department of Aerospace Information System and Artificial Muscle Research Center Konkuk University Seoul 143-701 Korea

We describe the design of four ornithopters ranging in wing span from 10 cm to 40 cm, and in weight from 5 g to 45 g. The controllability and power supply are two major considerations, so we compare the efficiency and characteristics between different types of subsystems such as gearbox and tail shape. Our current omithopter is radio-controlled with inbuilt visual sensing and capable of takeoff and landing. We also concentrate on its wing efficiency based on design inspired by a real insect wing and consider that aspects of insect flight such as delayed stall and wake capture are essential at such small size. Most importantly, the advance ratio, controlled either by enlarging the wing beat amplitude or raising the wing beat frequency, is the most significant factor in an ornithopter which mimics an insect.

关键词： biomimetic ornithopter flapping wing unsteady state low Reynolds number

中老年群体的BMI、久坐行为、身体活动水平、年龄歧视和老龄化焦虑的关系研究

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中老年群体的BMI、久坐行为、身体活动水平、年龄歧视和老龄化焦...

Modulating effect of ginseng saponins on heterologously expressed HERG currents in Xenopus oocytes

第二届陕西省体育科学大会

作者：李静 Seung-yong KIM Chae-Hee park

随着人口老龄化现象以惊人的速度席卷全球,各国都在积极推动健康老龄化和积极老龄化,身体活动不足和久坐行为已严重影响到人们的健康,甚至与全因死亡率和跌倒风险有关。年龄歧视和老龄化焦虑是实现健康老龄化的主要阻碍因素之一,老年人... 详细信息

随着人口老龄化现象以惊人的速度席卷全球,各国都在积极推动健康老龄化和积极老龄化,身体活动不足和久坐行为已严重影响到人们的健康,甚至与全因死亡率和跌倒风险有关。年龄歧视和老龄化焦虑是实现健康老龄化的主要阻碍因素之一,老年人的身心健康问题直接影响到整个社会的健康,是我们面临的重大课题。研究目的:调查中老年群体的BMI、久坐行为、身体活动水平,年龄歧视和老龄化焦虑的现状及其相互间的关联性,为即将步入老年阶段的中老年群体提高晚年幸福感,构建积极健康的老年生活提供基础资料。研究方法:采取随机抽样的方法于2023年在中国S地区选取264名中老年人(男性87名,女性177名)为调查对象。根据性别、BMI(kg/m2)、婚姻状况、吸烟状况、受教育程度、主观健康状况等因素分层对中老年群体的身体活动水平、年龄歧视和老龄化焦虑程度进行问卷测量。身体活动水平分为高强度(VPA)、中强度(MPA)、低强度(LP A),每次至少持续10分钟才记录为有效。数据分析使用SPSS 22.0和AMOS 25.0统计软件进行因子分析、t检验、Pearson's r、方差分析(ANOVA)和路径分析。研究结果:结果表明,61.8%的中老年群体的BMI值高于正常数值范围;中老年群体的久坐行为、身体活动水平的调查结果显示,男性的久坐行为、VPA、MPA均高于女性的水平;中老年群体的BMI与VPA呈负相关关系(r=-.148, p=.016),BMI与MPA呈负相关关系(r=-.164, p=.008),久坐行为与LPA成负相关关系(r=-.135, p=.028);中老年群体的年龄歧视与老龄化焦虑呈正相关关系(r=.539,p=.000)。结论:VPA和MPA不同程度会影响中老年群体的BMI指数,适当增加身体活动量,减少久坐行为,能有效降低老年人的BMI指数。为改善老龄化社会结构中的老龄化焦虑,实现健康老龄化,不仅需要社会结构层面的努力,还需要减少社会群体中的年龄歧视,提高个体对健康老龄化的再认识,促使中老年人为今后步入健康老年生活做好充分准备。

关键词： BMI 久坐行为身体活动年龄歧视老化焦虑

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Acta Pharmacologica Sinica 2005年第5期26卷 551-558页

作者： Cuk-seongKIM Sook-jinSON Hyo-shinKIM yong-dukKIM Kyu-seungLEE Byeong-hwaJEON kwang-jinKIM Jin-kyu park Jin-bong park Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea Korea Ginseng and Tobacco Research Institute Daejeon 305-805 Korea Department of Physiology College of Medicine Chungnam National University Daejeon 301-131 Korea

Aim:To examine the effects of ginseng saponins on the heterologously expressedhuman ether-a-go-go related gene（HERG）that encodes the rapid component ofthe delayed rectifier K+***:A two-electrode voltage clamp tech-nique was *** currents were recorded in Xenopus oocytes injected withHERG ***:Crude saponins of Korean red ginseng（GS）induced aminimal increase of the maximal HERG conductance without changes in the volt-age-dependent HERG current activation and inactivation ***,however,decelerated HERG current deactivation in a concentration-dependent manner,which was more noticeable with panaxitriol（PT）than panaxidiol（PD）.Consistently,ginseng saponins increased the HERG deactivation time constants with the orderof potency of Rg1（a maj or component of PT）>Rf1>Rb1（a major component of PD）.Re had little effect on HERG *** a cardiac action potential,GSincreased the outward HERG ***:Ginseng saponins enhanceHERG currents,which could be in part a possible mechanism of the shorteningcardiac action potential of ginseng saponins.

关键词： Ginseng saponins Xenopus laevis potassium channels action potentials patch-clamp techniques

Hepatocellular carcinoma in Budd-Chiari syndrome:A single center experience with long-term follow-up in South Korea

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World Journal of Gastroenterology 2012年第16期18卷 1946-1952页

作者： Hana park Jin Young Yoon Kyeong Hye park Do Young Kim Sang Hoon Ahn kwang-Hyub Han Chae Yoon Chon Jun yong park Department of Internal Medicine Yonsei University College of MedicineSeoul 120-752South Korea Institute of Gastroenterology Yonsei University College of MedicineSeoul 120-752South Korea Liver Cirrhosis Clinical Research Center Seoul 120-752South Korea Brain South Korea 21 Project for Medical Science Seoul 120-752South Korea

AIM:To evaluate long-term clinical course of BuddChiari syndrome(BCS) and predictive factors associated with the development of hepatocellular carcinoma(HCC) and ***:We analyzed 67 patients with BCS between June 1988 and May *** diagnosis of BCS was confirmed by hepatic venous outflow obstruction shown on abdominal ultrasound sonography,computed tomography,magnetic resonance imaging,or *** median follow-up period was 103 ± 156 [interquartile range(IQR)] ***:The median age of the patients was 47 ± 16(IQR) *** diagnosis,54 patients had cirrhosis,25(37.3%) Child-Pugh class A,23(34.3%) Child-Pugh class B,and six(9.0%) patients Child-Pugh class *** the follow-up period,HCC was developed in 17 patients,and the annual incidence of HCC in patients with BCS was 2.8%.Patients in HCC group(n = 17) had higher hepatic venous pressure gradient(HVPG) than those in non-HCC group(n = 50)(21 ± 12 mmHg vs 14 ± 7 mmHg,P = 0.019).The survival rate of BCS patients was 86.2% for 5 years,73.8% for 10 years,and 61.2% for 15 *** patients with BCS and HCC,survival was 79% for 5 years,43.1% for 10 years,and 21.5% for 15 ***:The incidence of HCC in patients with BCS was similar to that in patients with other etiologic cirrhosis in South *** HVPG is expected to provide additional information for predicting HCC development in BCS patients.

关键词： Budd-Chiari syndrome Hepatocellular carcinoma Prognosis

Settling and dewatering characteristics of granulated methane-oxidizing bacteria

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Journal of Environmental Sciences 2013年第2期25卷 280-286页

作者： kwang Ho Ahn kwang Soo Kim Sung Won Kang Chul yong Um Won Tae Lee kwang Baik Ko Korea Institute of Construction Technology 283Goyangdae-RoIlsanseo-GuGoyang-SiGyeonggi-Do 411-712Korea School of Civil and Environmental Engineering Yonsei UniversitySinchondong 134SudaemunguSeoul 120-749Korea School of Civil and Environmental Engineering Kumoh National Institute of TechnologyDaehak-ro 61GumiGyeongbuk 730-701Korea

We evaluated the settling ability and dewaterability of granulated methane-oxidizing bacteria （GMOB） after granulation using a continuous-flow reactor. A comparative analysis on settling and dewatering characteristics due to changes in sludge retention time （SRT, 10, 15 and 20 days） during cultivation of GMOB was conducted. In assessing dewaterability, the specific resistance to filtration （SRF） of activated sludge and GMOB was found to be 8.21×1013-2.38×1014 and 4.88 × 1012-1.98×1013 m/kg, respectively. It was confirmed that as SRT decreased, SRF of GMOB increased. In the case of bound extracellular polymeric substance （EPS）, activated sludge registered 147.5 mg/g-VSS while GMOB exhibited 171-177.2 mg/g-VSS. In the case of extracellular polymeric substance soluble EPS in effluent, activated sludge measured 62 mg/L and GMOB had 17.4-21.4 mg/L. The particle size analysis showed that mean particle diameters of GMOB were 402, 369, and 350 μm, respectively, at SRTs of 20, 15 and 10 days. In addition, it was found that GMOB had a larger mean particle diameter and exhibited much better settleability and dewaterability than activated sludge did.

关键词： methane-oxidizing bacteria dewaterability specific resistance to filtration extracellular polymeric substances

Practical Experience of Management of Urban parks at Home and Abroad

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Meteorological and Environmental Research 2024年第1期15卷 30-37页

作者： Wenqian LING yong ZHU Qinhuai XU Chengdu Institute of Planning&Design Chengdu 610061China

By systematically reviewing the practical experience of management of urban parks at home and abroad,the advanced experience in organization,management system,operation mechanism and social participation were summarized,and the optimization and improvement measures for the construction and management of urban parks in Chengdu were proposed to provide reference for the high-level construction,high-quality experience and efficient management of urban parks in the construction of park city demonstration zone in Chengdu.

关键词： Urban parks Management and operation Domestic and foreign experience Chengdu park city

Alpha-fetoprotein-targeted reporter gene expression imaging in hepatocellular carcinoma

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World Journal of Gastroenterology 2016年第27期22卷 6127-6134页

作者： kwang Il Kim Hye Kyung Chung Ju Hui park yong Jin Lee Joo Hyun Kang Molecular Imaging Research Center Korea Institute of Radiological and Medical Sciences Korea Drug Development Platform using Radio-Isotope Korea Institute of Radiological and Medical Sciences

Hepatocellular carcinoma (HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic mechanism of HCC and to evaluate novel therapeutic approaches. Molecular imaging is a convenient and up-to-date biomedical tool that enables the visualization, characterization and quantification of biologic processes in a living subject. Molecular imaging based on reporter gene expression, in particular, can elucidate tumor-specific events or processes by acquiring images of a reporter gene’s expression driven by tumor-specific enhancers/promoters. In this review, we discuss the advantages and disadvantages of various experimental HCC mouse models and we present in vivo images of tumor-specific reporter gene expression driven by an alpha-fetoprotein (AFP) enhancer/promoter system in a mouse model of HCC. The current mouse models of HCC development are established by xenograft, carcinogen induction and genetic engineering, representing the spectrum of tumor-inducing factors and tumor locations. The imaging analysis approach of reporter genes driven by AFP enhancer/promoter is presented for these different HCC mouse models. Such molecular imaging can provide longitudinal information about carcinogenesis and tumor progression. We expect that clinical application of AFP-targeted reporter gene expression imaging systems will be useful for the detection of AFP-expressing HCC tumors and screening of increased/decreased AFP levels due to disease or drug treatment.

关键词： Alpha-fetoprotein Hepatocellular carcinoma Molecular imaging Reporter gene Tumor-specific enhancer/promoter

In situ regulating intimately connected heterostructure by decomposition of solid solution oxides toward high-efficient water oxidation

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Rare Metals 2024年第4期43卷 1557-1569页

作者： Shao-Fei Zhang Xiao-Lu Yin Jin Wang Jian-Li Kang Tian-Tian Li Jin-Feng Sun yong-Qiang Meng Jian-Jiang Wang Dian-Long Wang Kai-Qiang Qin Hebei Key Laboratory of Flexible Functional Materials/Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018China Key Laboratory of Advanced Ceramics and Machining Technology/Ministry of Education School of Materials Science and EngineeringTianjin UniversityTianjin300072China Electrochemical Engine Center Department of Mechanical EngineeringPennsylvania State UniversityUniversity ParkPA16802USA

Heterogeneous interfaces produced by interdomain interactions on a nanoscale performs a crucial role in boosting the properties of an electrocatalyst toward oxygen evolution reaction(OER)***,a series of dual-phase electrodes with intimately connected heterointerfaces are prepared by in situ decomposing solid solution oxide of Ni_(x)Co_(y)Fe_(100-x-y)O,which grew on Ni foam massively via an ultrafast combustion ***,with high-reaction kinetics caused by the reduction treatment at 450℃,the less electronegative Fe and Co are more oxyphilic than Ni,which facilitated their co-exsolution and formation of CoFe_2O_4/NiO oxide with enriched oxygen *** from the nanoporous framework,heterojunction structure,and oxygen defects,the self-supporting electrodes present rapid charge/mass transmission and provide abundant active sites for *** optimized sample(R-SNCF4.5)shows low overpotentials of 226 and 324 mV at 10 and100 mA·cm^(-2),a small Tafel slope(46.7 mV·dec^(-1)),and excellent *** assembled R-SNCF4.5//Pt/C/NF electrolyzer demonstrates continuous electrolysis over 50 h at a current density of 10 mA·cm^(-2),under 1.51 *** functional theory(DFT)calculations verify that the strong electronic modulation plays a critical part in the CoFe_2O_4/NiO hybrid by lowering the energy barriers for the ratedetermining steps,and Fe sites are the most active OER sites.

关键词： Rapid combustion Decomposition of solid solution oxide Dual-phase heterostructure Oxygen evolution reaction Theoretical calculation