检索结果-南通市图书馆

Feature-based multiresolution techniques for product design

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第9期7卷 1535-1543页

作者： lee Sang Hun lee Kunwoo School of Mechanical and Automotive Engineering Kookmin University Seoul 136-702 Korea School of Mechanical and Aerospace Engineering Seoul National University Seoul 151-742 Korea

3D computer-aided design (CAD) systems based on feature-based solid modelling technique have been widely spread and used for product design. However, when part models associated with features are used in various downstream applications, simplified models in various levels of detail (LODs) are frequently more desirable than the full details of the parts. In particular, the need for feature-based multiresolution representation of a solid model representing an object at multiple LODs in the feature unit is increasing for engineering tasks. One challenge is to generate valid models at various LODs after an arbitrary rearrangement of features using a certain LOD criterion, because composite Boolean operations consisting of union and subtraction are not commutative. The other challenges are to devise proper topological framework for multiresolution representation, to suggest more reasonable LOD criteria, and to extend applications. This paper surveys the recent research on these issues.

关键词： Multiresolution Level of detail (LOD) Feature Solid Non-manifold

Influence of land use change on the waterbird community of Sihwa Lake,Republic of Korea

在线全文

学校读者我要写书评

暂无评论

Avian Research 2020年第3期11卷 349-362页

作者： Eunjae lee Junghee Sagong Yohan lee Urban Planning Research Division Daejeon Sejong Research InstituteDaejeonRepublic of Korea Dept.of Spatial&Environmental Planning Chungnam InstituteGongjuRepublic of Korea Department of Forest Resources and Landscape Architecture Yeungnam UniversityGyeongsanRepublic of Korea

Background:Land use and development alter mudflat and wetland habitat availability,although mudflats and wetlands provide important stopover habitats for shorebirds during the spring and autumn migrations and support communities of ducks and geese during the winter months in the Republic of *** study investigated land use changes around Sihwa Lake(Republic of Korea)and evaluated the effect of these changes on waterbird community ***:We conducted a land-use-change analysis at the medium-resolution level using land cover maps for 2001,2007,2009,and ***,a tidal stream survey was conducted in Sihwa Lake and the surrounding reclaimed mudflats every season for 10 years(2003-2012)to identify the seasonal and interannual variations in waterbird species *** determine the total annual waterbird species and population counts,species diversity index,and interspecies variations,a TRIM(trends and indices for monitoring data)analysis was ***:Wetland area decreased more than 10%while agricultural land,barren land,and grassland area increased more than 10%due to continuous reclamation activities around Sihwa *** land later turned into agricultural land or other land ***-three species and 566,623 individuals were *** number of species,population size,and species diversity index by year and by species showed decreasing trends that were more marked in spring and ***,seasonal and annual variations in waterbird species composition showed decreasing trends in dabbling ducks,herons,grebes,and shorebirds but diving ducks displayed increasing *** particular,shorebirds were reduced to a greater extent than other waterbird species because of the reduction and simplification of the intertidal zone,and shallow waters caused by reclamation and road ***:Increased development and construction around Sihwa Lake has altered migratory shorebird populations with a general decline in spe

关键词： Land use development Migratory bird populations Population trends Waterbird population size

A palynotaxonomic study of the genus Filipendula (Rosaceae)

在线全文

学校读者我要写书评

暂无评论

Journal of Systematics and Evolution 2009年第2期47卷 115-122页

作者： Sangtae lee Meekyung KANG Kyeong-In HEO Chunghee lee Department of Biology Sungkyunkwan University Division of Botanical Research Korea National Arboretum

Pollen grains from 15 species(18 taxa) of the genus Filipendula were examined with light and scan-ning electron *** was revealed that the pollen grains are isopolar,tricolporate,with scabrate or scabrate-microechinate *** pollen morphology was compared with the conventional classification sys-tems of the genus by different authors,and supported Shimizu’s system(1961),in which the genus was divided into three *** monotypic *** is characterized by pollen lacking fastigium and thickened costae *** other monotypic *** differs from others by pollen having larger grain,larger pore size,longitudinally elliptic fastigium and thickened costae *** largest *** is distinguished by pollen having rounded or latitudinally elliptic fastigium and thickened costae *** classification was not supported by the pollen morphology due to insufficient variability.

关键词： Filipendula palynology systematics

Techniques for overcoming atretic changes of the portal vein in living donor liver transplantation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2020年第4期19卷 311-317页

作者： Jeong-Moo lee Kwang-Woong lee Department of Surgery Seoul National University College of Medicine101 Daehak-roJongno-guSeoul 03080Korea

Background:Spontaneous diversion of the portal flow through collateral vessels into the systemic circulation is frequently observed in liver transplant recipients with severe portal *** induces main portal vein atretic change and modifies flow into the collateral even after donor graft *** atretic changes make liver transplantation *** this article we described several methods for overcoming this challenge by appropriate surgical ***:Three anastomotic techniques for living donor liver transplantation were performed in patients with atretic changes in the portal ***:The three techniques were(1)venoplasty to widen the diameter by using the recipient’s portal vein,and the diameter of the recipient’s portal vein was enlarged using their own portal vein stump patch;(2)conduit with cryopreserved vessels,and we dissected around the superior mesenteric vein and splenic vein junction and a conduit was built using the cryopreserved vessels;and(3)left gastric varix to portal vein anastomosis,if the recipients had large gastric varix and variceal wall was sufficiently thick for ***:Selection of optimal methods for portal vein anastomosis is essential in patients with atrophic change on the portal *** these methods are used aptly,they can be considered as favorable methods for overcoming each situation.

关键词： Atretic portal vein Liver transplantation Anastomosis

Friction Behavior of Magnetorheological Fluids with Different Material Types and Magnetic Field Strength

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2016年第1期29卷 84-90页

作者： ZHANG Peng lee Kwang-Hee lee Chul-Hee Department of Mechanical Engineering Inha University

Magnetorheological （MR） fluid is a type of a smart material that can control its mechanical properties under a magnetic field. Iron particles in MR fluid form chain structures in the direction of an applied magnetic field, which is known as MR effect, resulting in variation of stiffness, shear modulus, damping and tribological characteristics of MR fluid. As MR effect depends on the density of particles in the fluid or the strength of a magnetic field, the experiments are conducted to evaluate the friction property under reciprocating motion by changing the types of MR fluid and the strength of a magnetic field. The material of aluminum, brass, and steel are chosen for specimen as they are the most common material in mechanical applications. The surfaces of specimen are also observed by optical microscope before and after experiments to compare the surfaces with test conditions. The comparing results show that the friction coefficient increases as the strength of a magnetic field increases in regardless of types of MR fluid or the material. Also the density of particle in MR fluid affects the friction characteristic. The results from this research can be used to improve the performance of mechanical applications using MR fluid.

关键词： Magnetorheological (MR) fluid friction characteristics smart material magnetic field

Enhancing Identity Protection in Metaverse-Based Psychological Counseling System

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 617-632页

作者： Jun lee Hanna lee Seong Chan lee Hyun Kwon Department of Game Software Hoseo UniversityAsan-si31499Korea Yatav Enter Seoul04799Korea Department of Artificial Intelligence and Data Science Korea Military AcademySeoul01805Korea

Non-face-to-face psychological counseling systems rely on network technologies to anonymize information regard-ing client ***,these systems often face challenges concerning voice data leaks and the suboptimal communication of the client’s non-verbal expressions,such as facial cues,to the *** study proposes a metaverse-based psychological counseling system designed to enhance client identity protection while ensuring efficient information delivery to counselors during non-face-to-face *** proposed systemincorporates a voicemodulation function that instantlymodifies/masks the client’s voice to safeguard their ***,it employs real-time client facial expression recognition using an ensemble of decision trees to mirror the client’s non-verbal expressions through their avatar in the metaverse *** system is adaptable for use on personal computers and smartphones,offering users the flexibility to access metaverse-based psychological counseling across diverse *** performance evaluation of the proposed system confirmed that the voice modulation and real-time facial expression replication consistently achieve an average speed of 48.32 frames per second or higher,even when tested on the least powerful smartphone ***,a total of 550 actual psychological counseling sessions were conducted,and the average satisfaction rating reached 4.46 on a 5-point *** indicates that clients experienced improved identity protection compared to conventional non-face-to-face metaverse counseling ***,the counselor successfully addressed the challenge of conveying non-verbal cues from clients who typically struggled with non-face-to-face psychological *** proposed systemholds significant potential for applications in interactive discussions and educational activities in the metaverse.

关键词： Metaverse counseling system face tracking identity protection

2D material inorganic liquid crystals for tunable deep UV light modulation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2022年第12期9卷 62-63页

作者： Young Hee lee Department of Energy Science and Department of Physics Sungkyunkwan University IBS Center for Integrated Nanostructure Physics Institute for Basic Science Sungkyunkwan University

Modulation of light refers to the modulation of electromagnetic radiation in the optical region including visible light as well as ultraviolet and infrared radiation,in which the amplitude (and therefore the intensity),phase,frequency or polarization of the radiated oscillations can be changed [1].Optical modulator devices are widely used in industry,as represented by liquid crystal optical modulators having an annual global market worth of over US$100 ***,

关键词：

Goal-Based Automated Code Generation in Self-Adaptive System

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2010年第6期25卷 1118-1129页

作者： Joonhoon lee Jeongmin Park Giljong Yoo Eunseok lee Department of Electrical and Computer Engineering Sungkyunkwan University Department of Software Engineering Dongyang Mirae University

System administrator deals with many problems,as computing environment becomes increasingly *** with an ability to recognize system states and adapt to resolve these problems offer a *** experience and knowledge are required to build a self-adaptive ***-adaptive systems have inherent *** paper proposes a technique that automatically generates the code for the self-adaptive *** the system is easier to ***-adaptive systems of previous research required high system resource *** operation could be invoked by external factors such as *** propose an improved self-adaptive system approach and apply it to video conference system and robot *** compared the lines of code,the number of classes created by the *** have confirmed this enhanced approach to be effective in reducing these development metrics.

关键词： self-adaptive self-healing goal graph activation switch error detection

The genetic variation in Monocarboxylic acid transporter 2 （MCT2） has functional and clinical relevance with male infertility

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2014年第5期16卷 694-697,I0007页

作者： Jinu lee Dong Ryul lee Suman lee Yonsei Institute of Pharmaceutical Sciences College of Pharmacy Yonsei University Incheon Department of Biomedical Science CHA University Seongnam-si Korea

Monocarboxylic acid transporter 2 （MCT2） transports pyruvate and lactate outside and inside of sperms, mainly as energy sources and plays roles in the regulation of spermatogenesis. We investigated the association among genetic variations in the MCT2 gene, male infertility and MCT2 expression levels in sperm. The functional and genetic significance of the intron 2 （＋28201A 〉 G, rs10506398） and 3＇ untranslated region （UTR） single nucleotide polymorphism （SNP）（＋2626G 〉 A, rs10506399） of MCT2 variants were investigated. Two MCT2 polymorphisms were associated with male infertility （n = 471, P 〈 0.05）. In particular, the MCT2-3＇ UTR SNP （＋2626 G 〉 A） had a strong association with the oligoasthenoteratozoospermia （OAT） group. The ＋2626GG type had an almost 2.4-fold higher sperm count than that of the ＋2626AA type （＋2626GG; 66 x 106 vs ＋2626AA; 27 x 106, P 〈 0.0001）. The MCT2-3＇ UTR SNP may be important for expression, as it is located at the MCT2 3＇ UTR. The average MCT2 protein amount in sperm of the ＋2626GG type was about two times higher than that of the ＋2626AA type. The results suggest that genetic variation in MCT2 has functional and clinical relevance with male infertility.

关键词： 3' UTR male infertility monocarboxylic acid transporter 2 single nucleotide polymorphism sperm