检索结果-南通市图书馆

The Role of Relative Spinal Motion during Feline Galloping for Speed Performance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2014年第4期11卷 517-528页

作者： Young Kook kim Jongwon Park Byungho Yoon kyung-Soo kim Soohyun kim Robotics Program Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Republic of Korea Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Republic of Korea

Felines use their spinal column to increase their running speed at rapid locomotion performance. However, its motion profile behavior during fast gait locomotion has little attention. The goal of this study is to examine the relative spinal motion profile during two different galloping gait speeds. To understand this dynamic behavior trend, a dynamic motion of the feline animal （Felis catus domestica） was measured and analyzed by motion capture devices. Based on the experiments at two different galloping gaits, we observed a significant increase in speed （from 3.2 m.s-1 to 4.33 m.s-1） during the relative motion profile synchronization between the spinal （range： 118.86~ to 168.00~） and pelvic segments （range： 46.35~ to 91.13~） during the hindlimb stance phase （time interval： 0.495 s to 0.600 s）. Based on this discovery, the relative angular speed profile was applied to understand the possibility that the role of the relative motion match during high speed locomotion generates bigger ground reaction force.

关键词： feline galloping galloping gait pattern relative spinal motion speed performance phase match

Insulinotrophic and hypolipidemic effects of Ecklonia cava in streptozotocin-induced diabetic mice

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2012年第5期5卷 374-379页

作者： Mi-Ja kim Hye kyung kim Department of Food and Biotechnology Hanseo UniversitySeosan 356-706Republic of Korea Department of Pharmacology school of MedicineKyunghee UniversitySeoul 130-701Republic of Korea

Objective:To explore the anti-diabetic activity of Ecklonia cava(EC) in streptozotocin(STZ)-induced diabetic ***:Diabetes was induced by a single intraperitoneal injection of STZ(90 mg/kg).Normal and diabetic mice were treated with 0%,3%,and 5%EC diet for 4 weeks. Serum glucose and insulin concentrations,serum lipid profile,oral glucose tolerance test,and liver and pancreaticβ-cell histopathological observations were *** addition,in vitro glucose-induced insulin secretion was determined using pancreaticβ-islet ***:EC supplementation significantly and dose-dependently decreased serum glucose concentration, and improved glucose homeostasis in diabetic mice by preventing loss ofβ-cell mass resulting in increase of insulin *** triglyceride and total cholesterol concentrations in the serum and liver were markedly reduced by EC treatment in STZ-diabetic ***,LDL-,and HDL-cholesterol levels were ameliorated in EC supplemented diabetic *** steatosis induced by STZ was ameliorated by EC ***,in vitro insulinotrophic effect of EC extract was observed in pancreaticβ-***:This study demonstrated that EC is a potent and efficacious hypoglycemic and hypolipidemic agent,and prevents the loss ofβ-cell mass resulting in increase of insulin secretary capacity.

关键词： Diabetes Streptozotocin Insulin Lipid profile Pancreaticβ-cell

Management of post-gastrectomy anastomosis site obstruction with a self-expandable metallic stent

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2015年第16期21卷 5110-5114页

作者： Ra Ri Cha Sang Soo Lee Hyunjin kim Hong Jun kim tae-Hyo kim Woon tae Jung Ok Jae Lee kyung Soo Bae Sang-Ho Jeong Chang Yoon Ha Department of Internal Medicine Gyeongsang National University School of Medicine Department of Radiology Gyeongsang National University School of Medicine Department of Surgery Gyeongsang National University School of Medicine

Post-gastrectomy anastomosis site obstruction is a relatively rare complication after a subtotal *** present a case of a 75-year-old man who underwent a truncal vagotomy, omental patch, gastrojejunostomy, and Braun anastomosis for duodenal ulcer perforation and a gastric outlet *** the 10 th postoperative day, the patient complained of abdominal discomfort and *** diagnosed post-gastrectomy anastomosis site obstruction by an upper gastrointestinal series and an upper endoscopic *** inserted a self-expandable metallic stent(SEMS) at the anastomosis *** stent was fully expanded after *** the day following the stent insertion, the patient began to eat, and his abdominal discomfort was *** paper describes the successful management of post-gastrectomy anastomosis site obstruction with temporary placement of a SEMS.

关键词： Efferent loop syndrome Postgastrectomysyndrome self-expandable metallic stent

Morphology Control of Bi2S3 Nanostructures and the Formation Mechanism

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2013年第6期31卷 752-756页

作者： HeeJin kim Ji-eun Park kyung kim Mi-kyung Han Sung-Jin kim Wooyoung Lee Department of Materials Science and Engineering Yonsei University Seou1120- 749 Korea Department of Chemistry and Nano Science Ewha Womans University Seoul 120-750 Korea

Bismuthinite （Bi2S3）nanostructures were prepared by a hydrothermal method with sodium ethylenediamine- tetraacetate （EDTA-Na2）. The morphology of Bi2S3 nanostructures was changed from a nanorod to a nanoplate by presence of the EDTA-Na2. The altered morphology was caused by the capping effect of EDTA-Na2 with Bi3＋ ions, which induces the suboptimal growth direction due to partially blocking the preferential orientation direction. When the EDTA-Na2/Bi3＋ molar ratio= 1, the growth of Bi2S3 nanostructures was not allowed due to the chelating effect of EDTA-Na2. The obtained Bi2S3 nanorods, stacked nanorods, nanoplates and nanoparticles were characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEM）, high-resolution transmission electron mi- croscopy （HRTEM） and selected area electron diffraction （SAED） pattern. A possible formation mechanism of these morphologies was proposed. The successful synthesis of various morphologies of nanostructured Bi2S3 may open up new possibilities for thermoelectric, electronic and optoelectronic uses of nanodevices based on Bi2S3 nanostructure.

关键词： bismuth sulfide (Bi2S3) hydrothermal nanorod nanoplate thermoelectric material

The validity of the Reynolds equation in spool valve analysis considering cavitation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2016年第3期4卷 266-276页

作者： Sung-Ho HONG kyung-Woong kim School of Mechanical Aerospace & Systems Engineering Korea Advanced Institute of Science and Technology 291 Daehak-ro Yuseong-guDaejeon 305-701 Republic of Korea

The purpose of this research is to investigate the validity of the Reynolds equation in spool valve analysis under cavitation. This study is carried out for a laminar and isothermal flow between a sleeve and spool with grooves. The pressure and lateral force obtained from the Reynolds equation and the Navier-Stokes equation are compared with variations of aspect ratio, cross sectional area, and number of grooves. The cavitation phenomenon is considered by using a cavitation model in the Navier-Stokes equation and the Reynolds cavitation boundary condition in the Reynolds equation. A large difference of more than 20% is found between the equations for a lateral force of spool valve with many grooves. It was found that the Reynolds equation is not suitable for calculation of a lateral force of the spool valve with multiple-grooves of which the width and depth are even larger than the clearance under cavitation.

关键词： validity Reynolds equation Navier-Stokes equation spool valve cavitation

Study of Spiral Flow Generated through an Annular Slit

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2005年第2期14卷 97-102页

作者： tae Hun kim Shigeru MATSUO Toshiaki SETOGUCHI Heuy-Dong kim Graduate school of Science and Technology Saga University 1Honjo-machiSaga shiSaga 840-8502JapanDepartment of Mechanical Engineering Saga University1Honjo-machiSaga shiSaga 840-8502JapanDepartment of Mechanical Engineering Saga University1Honjo-machiSaga shiSaga 840-8502JapanSchool of Mechanical Engineering College of Natural ScienceAndong National University388Song Cheon DongAndongKyung PookKorea

The effect of pressurized air inlets in the reservoir upstream of the annular slit on characteristics of the axial and tangential velocity components is investigated numerically, and the mechanism of occurrence of spiral nozzle flow is clarified. In simulations, Unified Platform for Aerospace Computational Simulation (UPACS) is used. The governing equations under consideration are the unsteady compressible Navier - Stokes. A second-order finite volume scheme with MUSCL (Roe scheme) is used to discretize the spatial derivatives, and a second order-central difference scheme for the viscous terms, and a MFGS (Matrix Free Gauss Seidel) is employed for time integration. Spalart-Allmaras model was used as a turbulence model. The results obtained are compared with velocity distributions in the experiment measured by the two-component fiber optic laser Doppler velocimeter system. The existence of discrete pressurized air inlets that leads to the occurrence of asymmetrical characteristics is a very important factor for the formation of spiral flow.

关键词： spiral nozzle flow Coanda effect convergent nozzle annular slit simulation.

Degenerate s-Extended Complete and Incomplete Lah-Bell Polynomials

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2022年第6期130卷 1479-1495页

作者： Hye kyung kim Dae Sik Lee Department of Mathematics Education Daegu Catholic UniversityGyeongsan38430Korea School of Electronic and Electric Engineering Daegu UniversityGyeongsan38453Korea

Degenerate versions of special polynomials and numbers applied to social problems,physics,and applied mathematics have been studied variously in recent ***,the(s-)Lah numbers have many other interesting applications in analysis and *** this paper,we divide two *** first introduce new types of both degenerate incomplete and complete s-Bell polynomials respectively and investigate some properties of them ***,we introduce the degenerate versions of complete and incomplete Lah-Bell polynomials as multivariate forms for a new type of degenerate s-extended Lah-Bell polynomials and numbers *** investigate relations between these polynomials and degenerate incomplete and complete s-Bell polynomials,and derive explicit formulas for these polynomials.

关键词： Lah-Bell numbers and polynomials s-extended Lah-Bell numbers and polynomials complete s-Bell polynomials incomplete s-Bell polynomials s-Stirling numbers of second kind

Modified analogue forecasting in the hidden Markov frameworkfor meteorological droughts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2019年第1期62卷 151-162页

作者： CHEN Si CHUNG GunHui kim Byung Sik kim tae-Woong Department of Civil and Environmental Engineering Hanyang University Department of Civil Engineering Hoseo University Department of Urban Environmental Disaster Prevention Engineering Kangwon National University

An analogue method(AM) is a nonparametric approach that has been applied to predict the future states of a dynamic system by following the evolution of the analogues in the historical archive. In this study, we proposed a hidden Markov model(HMM)framework for a modified analogue forecasting(MAF) approach for meteorological droughts in Korea. The unobservable(hidden) state process in the framework aims to model the underlying drought state, while the observation process was formed from the time series of the standardized precipitation index(SPI) as a drought index. Within the framework, the likelihood estimator was used as the measure of similarity between past SPI analogues and current data. The MAF approach was conducted on the selected analogues to make forecasts at lead times of one and three months. The proposed model was applied to five selected stations in Korea using the SPI data from 1973 to 2016. The forecasting performance of the proposed model was tested during the validation period(2003–2016) using several statistical criteria and it was compared to a persistence-based benchmark model. The results showed significant improvement in the forecasting capacity, and satisfactory performance for numerical SPI forecasting and categorical drought forecasting. The results also suggested that the proposed model was able to provide useful information for determining future drought categories for early drought warning with a lead time of up to three months.

关键词： modified analogue forecasting hidden Markov model meteorological drought standardized precipitation index

Comparative toxicity of silver nanoparticles and silver ions to Escherichia coli

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2018年第4期30卷 50-60页

作者： Yoojin Choi Hyun-A kim Kyoung-Woong kim Byung-tae Lee Department of Chemical and Biomolecular Engineering (BK21 Plus Program) Korea Advanced Institute of Science and Technology (KAIST) School of Earth Sciences and Environmental Engineering Gwangju Institute of Science and Technology (GIST)

With the increase in silver（Ag）-based products in our lives, it is essential to test the potential toxicity of silver nanoparticles（Ag NPs） and silver ions（Ag ions） on living organisms under various conditions. Here, we investigated the toxicity of Ag NPs with Ag ions to Escherichia coli K-12 strain under various conditions. We observed that both Ag NPs and Ag ions display antibacterial activities, and that Ag ions had higher toxicity to E. coli K-12 strain than Ag NPs under the same concentrations. To understand the toxicity of Ag NPs at a cellular level, reactive oxygen species（ROS） enzymes were detected for use as antioxidant enzymatic biomarkers. We have also studied the toxicity of Ag NPs and Ag ions under various coexistence conditions including： fixed total concentration, with a varied the ratio of Ag NPs to Ag ions; fixed the Ag NPs concentration and then increased the Ag ions concentration; fixed Ag ions concentration and then increasing the Ag NPs *** to Ag NPs and Ag ions clearly had synergistic toxicity; however, decreased toxicity（for a fixed Ag NPs concentration of 5 mg/L, after increasing the Ag ions concentration） to E. coli K-12 strain. Ag NPs and Ag ions in the presence of L-cysteine accelerated the bacterial cell growth rate, thereby reducing the bioavailability of Ag ions released from Ag NPs under the single and coexistence conditions. Further works are needed to consider this potential for Ag NPs and Ag ions toxicity across a range of environmental *** Significance Statement： As silver nanoparticles（Ag NPs）-based products are being broadly used in commercial industries, an ecotoxicological understanding of the Ag NPs being released into the environment should be further considered. Here, we investigate the comparative toxicity of Ag NPs and silver ions（Ag ions） to Escherichia coli K-12 strain, a representative ecotoxicological bioreporter. This study showed that toxicities of Ag NPs and Ag ions to E. coli

关键词： Nanotoxicity Silver nanoparticles Silver ions Coexist condition Escherichia coli