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Journal of Central South University 2014年第9期21卷 3513-3517页

作者： Kee-young kwon College of Engineering Kongju National University

The effect of channel-width chirping on near- and far-field intensity patterns of the six supermodes was investigated. The supermode discrimination was evaluated in various channel-chirped index guided laser arrays. The results show that the linearly channel-chirped laser array has very good supermode discrimination which is better than that of a uniform laser array, the V channel-chirped laser array has the smallest radiation angle of the fundamental supermode among the calculated arrays, and the asymmetrically V channel-chirped array has a very small radiation angle of the fundamental supermode, which is smaller than that of the uniform array and also allows for very good fundamental supermode discrimination against the higher-order supermodes, which is better than that of the V channel-chirped laser array.

关键词： laser array channel-width chirping field pattern modal gain

Experimental and Computational Studies on Coanda Nozzle Flow for the Air Knife Application

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Journal of Thermal Science 2007年第2期16卷 164-169页

作者： Soon-Bum kwon Dong-Won LEE young-Doo kwon School of Mechanical Engineering Kyungpook National University1370Sankyuk-dongDaegu 702-701Korea

To control the film thickness of zinc in the process of continuous hot-dip galvanizing, it is known from the early days that the gas wiping through an air knife is the most effective one. The gas wiping using in galvanizing process brings about a problem of splashing from the strip edge for a certain high speed of coating. So, in the present study, the effects of the deflection angle of Coanda nozzle on jet structure and the distribution of impinging pres- sure at the plate surface are investigated numerically and experimentally. In numerical analysis, the governing equations consisted of three-dimensional time dependent full Navier-Stokes equations, standard k-ε turbulence model to solve turbulent stTess and so on are employed. In experiment, 16 channel pressure scanning valve and 3-axis auto traversing unit are used to measure the impinging pressure at the strip surface. As a result, it is found that the smaller the deflection angle for the same nozzle slit of air knife is, the larger the impinging pressure is. To reduce the size of separation bubble and to enhance the cutting ability, it is recommendable to use an air knife with the Coanda nozzle.

关键词： Air knife Coanda effect edge splashing gas wiping hot-dip galvanizing impinging jet

Factors associated with use of gastric cancer screening services in Korea

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World Journal of Gastroenterology 2009年第29期15卷 3653-3659页

作者： young Min kwon Hyung Taek Lim Kiheon Lee Be Long cho Min Sun Park Ki young Son Sang Min Park Department of Family Medicine Seoul National University Hospital Seoul National University College of Medicine 28 Yunkeon-dong Jongro-gu Seoul 110-744 South Korea Department of Medicine Yonsei University College of Medicine 134 Shinchon-dong Seodaemun-gu Seoul 120-752 South Korea Department of Family Medicine Seoul National University Bundang Hospital and Department of the History of Medicine and Medical Humanities Seoul National University College of Medicine 166 Gumi-ro Bundang-gu Seongnam-si Gyeonggi-do 463-707 South Korea

AIM: To identify the factors associated with participation in gastric cancer screening programs. METHODS: Using data from the Korea National Health and Nutrition Examination Survey 2005 (KNHANES Ⅲ), a nationwide health-related surveyin Korea, a cross-sectional study was performed to investigate the multiple factors associated with gastric cancer screening attendance among persons aged at least 40 years. The study population included 4593 individuals who completed a gastric cancer screening questionnaire and had no previous cancer history. Four groups ofindividual-level or environmental level covariates were considered as potential associated ***: Using KNHANES Ⅲdata, an estimated31.71% of Korean individuals aged at least 40 years adhered to gastric cancer screening recommendations. Subjects who graduated from elementary school[adjusted odds ratio (aOR), 1.66; 95% CI: 1.21-2.26], middle/high school (aOR, 1.38; 95% CI: 1.01-1.89), and university or higher (aOR, 1.64; 95% CI: 1.13-2.37) were more likely to undergo gastric cancer screening than those who received no formal education at all. The population with the highest income tertile had more attendance at gastric screening compared to those with the lowest income tertile (aOR, 1.36; 95% CI: 1.06-1.73). Gastric screening was also negatively associated with excessive alcohol consumption (aOR, 0.71; 95% CI: 0.53-0.96). A positive attitude to preventive medical evaluation was significantly associated with better participation in gastric cancer screening programs (aOR, 5.26; 95% CI: 4.35-6.35). CONCLUSION: Targeted interventions for vulnerable populations and public campaigns about preventive medical evaluation are needed to increase gastric cancer screening participation and reduce gastric cancer mortality.

关键词： Socioeconomic factors Health behavior Health status disparity Mental health Early detectionof cancer

Effects of a dynamic membrane formed with polyethylene glycol on the ultrafiltration of natural organic matter

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Frontiers of Environmental Science & Engineering 2010年第2期4卷 172-182页

作者： Boksoon kwon Noeon PARK Jaeweon cho Woongjin R&D Center San 4-1Nakseongdae-dongGwanak-guSeoul 151-057Korea Korea Institute of S&T Evaluation and Planning Yangjae-dongSeocho-guSeoul 137-130Korea Department of Environmental Science and Engineering GIST1 Oryong-dongBuk-guGwangju 500-712Korea

The formation of a dynamic membrane(DM)was investigated using polyethylene glycol(PEG)(molecular weight of 35000 g/mol,concentration of 1 g/L).Two natural organic matters(NOM),Dongbok Lake NOM(DLNOM)and Suwannee River NOM(SRNOM)were used in the ultrafiltration experiments along with *** evaluate the effects of the DM with PEG on ultrafiltration,various transport experiments were conducted,and the analyses of the NOM in the membrane feed and permeate were performed using high performance size exclusion chromatography,and the effective pore size distribution(effective PSD)and effective molecular weight cut off(effective MWCO)were *** advantages of DM formed with PEG can be summarized as follows:(1)PEG interferes with NOM transmission through the ultrafiltration membrane pores by increasing the retention coefficient of NOM in UF membranes,and(2)low removal of NOM by the DM is affected by external factors,such as pressure increases during UF membrane filtration,which decreases the effective PSD and effective MWCO of UF ***,a disadvantage of the DM with PEG was severe flux decline;thus,one must be mindful of both the positive and negative influences of the DM when optimizing the UF performance of the membrane.

关键词： dynamic membrane natural organic matters ultrafiltration membrane performance effective PSD effective molecular weight cutoff

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Neural Regeneration Research 2011年第4期6卷 283-287页

作者： Sung Ho Jang Sang-Hyun cho Mi young Lee Yong Hyun kwon Min Cheul Chang Department of Physical Medicine and Rehabilitation College of MedicineYeungnam UniversityDaegu 705-717Republic of Korea Department of Physical Therapy Institute of Health ScienceYonsei University College of Health ScienceWounju-siGangwon-do 220-710Republic of Korea Department of Physical Therapy College of Health and TherapyDaegu Haany UniversitySuseongkuDaegu 706-060Republic of Korea Department of Physical Therapy Yeungnam College of Science and TechnologyNamkuDaegu 705-703Republic of Korea

The corticospinal tract （CST） is one of the most important neural tracts for motor function in the human brain. Little is known about age-related changes of the CST. tn this study, we tried to evaluate age-related changes of the CST using diffusion tensor imaging in 60 healthy subjects. The diffusion tensor imaging result revealed that the tract number and fractional anisotropy value were decreased, and the apparent diffusion coefficient （ADC） value was increased with aging. The distribution showed a semilog pattern for tract number, fractional anisotropy and ADC of the CST, and the pattern of each graph was near-linear. When compared with the diffusion tensor imaging parameters of subjects in the 20 s age group, tract number and fractional anisotropy values were significantly decreased in the 50 s-70 s age groups. Likewise, the ADC value was significantly higher in the 50 s-70 s age groups. The CST in the brain of normal subjects degenerated continuously from the 20 s to the 70 s, with a near-linear pattern, and degeneration of the CST began to manifest significantly in the subjects in their 50 s, compared with the subjects in their 20 s.

关键词： corticospinal tract motor function aging diffusion tensor imaging

Hybrid electrodes effective for both electrowetting-and dielectrowetting-driven digital microfluidics

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Droplet 2023年第3期2卷 60-67页

作者： Hongyao Geng Sung kwon cho Department of Mechanical Engineering and Materials Science University of PittsburghPittsburghPennsylvaniaUSA

Electrowetting on dielectric(EWOD)and dielectrowetting(DEW)are two major principles to drive droplets in digital *** is effective to manipulate(create,transport,split,and merge)conductive droplets being currently used for many biological,chemical,and optical *** can also manipulate droplets but more efficiently with dielectric(nonconductive)fluids.A digital microfluidic platform efficiently operable by both EWOD and DEW would offer higher versatility in handling a wide range of fluids,regardless of their *** this regard,this article presents a new hybrid electrode design enabling EWOD and DEW to drive various kinds of droplet fluids on a single *** addition,a slippery liquid-infused surface(SLIPS)is integrated with the hybrid *** SLIPS is well known to resist biofouling and repel sticky fluids,which endows the hybrid electrodes with much wider application *** a result,the present SLIPS-integrated hybrid electrodes facilitate actuating various kinds of fluids which would not be driven by conventional EWOD and/or DEW *** paper presents the successful transportation of not only conductive fluids including water,protein solution,glycerol,and honey but also nonconductive fluids including dodecane,silicone oil,and light and heavy crude oil,all driven by the SLIPS-integrated hybrid *** performance comparisons among solid,interdigitating,and hybrid electrodes are made by testing both conductive and nonconductive droplets.

关键词： dielectric fluid fouling

Decomposing Composite Changes for Code Review and Regression Test Selection in Evolving Software

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Journal of Computer Science & Technology 2019年第2期34卷 416-436页

作者： Bo Guo young-Woo kwon Myoungkyu Song Department of Global Operations PayPal Omaha Nebraska 68128 U.S.A. School of Computer Science and Engineering Kyungpook National University Daegu 702-701 South Korea Department of Computer Science University of Nebraska at Omaha Omaha 68128 U.S.A.

Inspecting and testing code changes typically require a significant amount of developer *** a system evolves,developers often create composite changes by mixing multiple development issues,as opposed to addressing one independent issue—an atomic *** composite changes often becomes time-consuming and *** test unrelated edits on composite changes,rerunning all regression tests may require excessive *** address the problem,we present an interactive technique for change decomposition to support code reviews and regression test selection,called *** a developer specifies code change within a diff patch,ChgCutter partitions composite changes into a set of related atomic changes,which is more cohesive and self-contained regarding the issue being *** composite change inspection,it generates an intermediate program version that only includes a related change subset using program dependence *** cost reduction during regression testing,it safely selects only affected tests responsible for changes to an intermediate *** the evaluation,we apply ChgCutter to 28 composite changes in four open source *** partitions these changes with 95.7% accuracy,while selecting affected tests with 89.0% *** conduct a user study with professional software engineers at PayPal and find that ChgCutter is helpful in understanding and validating composite changes,scaling to industry projects.

关键词： software maintenance and evolution code review test selection program slicing

Suppression of gold nanoparticle agglomeration and its separation via nylon membranes

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Chinese Journal of Chemical Engineering 2017年第7期25卷 931-937页

作者： Ayyavoo Jayalakshmi In-Chul Kim young-Nam kwon School of Urban and Environmental Engineering Ulsan National Institute of Sdence and TechnologyUlsan 689-798Korea KIST-UNIST UIsan Center for Convergent Materials UNIST(Ulsan National Institute of Science and Technology)Korea Environment and Resources Research Center Korea Research Institute Chemical TechnologyDaejeon 305-606Korea

Use of ultraporous nylon membrane is one of the most widely employed techniques for removal of hard and soft nanoparticles in the semiconductor industry, and the accurate determination of membrane pore size is necessary in order to avoid manufacturing defects caused by contamination. The gold nanoparticle has several benefits for the evaluation of polymeric membranes; however, the nanoparticles agglomerate easily on the nylon membrane and make it difficult to evaluate the membrane precisely. The properties of 2-amino-2-hydroxymethyl-1,3-propanediol(ADP) ligand in gold nanoparticle solution were systematically investigated, and ADP was utilized for improved evaluation of the nylon membranes. Nylon membrane used in this study was prepared by phase inversion techniques. Ultrathin dense layer on top of the membrane surface and Darcy structures in the microporous membrane support were observed. The gold particle rejection was carried out at various p H values from 4 to14 and higher rejection was observed at p H 4 and 8. The suppression of gold colloid agglomeration using ADP and monodispersity of gold colloids was also analyzed by confocal laser scanning microscopy(CLSM), transmission electron microscopy(TEM), and scanning electron microscopy(SEM). van der Waals interaction energy of the particles was reduced in the addition of ADP. The presence of ADP ligand in the gold solutions prevented the agglomeration of gold nanoparticles and reduced the adsorption of the particles on the nylon membrane surface,leading to precise evaluation of membrane pore sizes.

关键词： Particle size Electron microscopy Gold colloid flock Semiconductor

Ever-changing endoscopic treatment for early gastric cancer:Yesterday-today-tomorrow

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World Journal of Gastroenterology 2014年第37期20卷 13273-13283页

作者： Mi-young Kim Jun-Hyung cho Joo young cho Digestive Disease Center Soonchunhyang University Hospital

Endoscopic resection has been an optimal treatment for selected patients with early gastric cancer(EGC) based on advances in endoscopic instruments and techniques. As endoscopic submucosal dissection(ESD) has been widely used for treatment of EGC along with expanding ESD indication, concerns have been asked to achieve curative resection for EGC while guaranteeing precise prediction of lymph node metastasis(LNM). Recently, new techniques including ESD or endoscopic full-thickness resection combined with sentinel node navigation enable minimal tumor resection and a laparoscopic lymphadenectomy in cases of EGC with high risk of LNM. This review covers the development and challenges of endoscopic treatment for EGC. Moreover, a new microscopic imaging and endoscopic techniques for precise endoscopic diagnosis and minimally invasive treatment of EGC are introduced.

关键词： Endoscopic resection Early gastric cancer Confocal laser endomicroscopy Sentinel node navigation Hybrid natural orifice transluminal endoscopic surgery

Enumerating Abelian Typical Cube-Free Fold Coverings of a Circulant Graph

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Algebra Colloquium 2020年第1期27卷 137-148页

作者： young Soo kwon Jaeun Lee Department of Mathematics Yeungnam UniversityKyongsan712-749Korea

Enumerating the isomorphism or equivalence classes of several types of graph coverings is one of the central research topics in enumerative topological graph theory.A covering projection p from a Cayley graph Cay(Г,X)onto another Cayley graph Cay(Q,y)is called typical if the function p:Г→Q on the vertex sets is a group epimorphism.A typical covering is called abelian(or circulant,respectively)if its covering graph is a Cayley graph on an abelism(or a cyclic,respectively)***,the equivalence classes of connected abelian typical prime-fold coverings of a circulant graph are *** a continuation of this work,we enumerate the equivalence classes of connected abelian typical cube-free fold coverings of a circulant graph.

关键词： graph covering enumeration voltage assignment circulant graph