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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1694-1707页

作者： Jinhyung KIM Dongwon jeong Doo-Kwon BAIK Department of Computer Science and Engineering Korea UniversitySeoul 136-713Korea Department of Informatics and Statistics Kunsan National UniversityKunsan 573-701Korea

In this paper,we propose a new relational schema (R-schema) to XML schema translation algorithm, VQT, which analyzes the value cardinality and user query patterns and extracts the implicit referential integrities by using the cardinality property of foreign key constraints between columns and the equi-join characteristic in user queries. The VQT algorithm can apply the extracted implied referential integrity relation information to the R-schema and create an XML schema as the final result. Therefore, the VQT algorithm prevents the R-schema from being incorrectly converted into the XML schema, and it richly and powerfully represents all the information in the R-schema by creating an XML schema as the translation result on behalf of the XML DTD.

关键词： Value cardinality Query pattern Relational schema XML schema Implicit referential integrity relations Explicit referential integrity

An XPath-based OWL storage model for effective ontology management in Semantic Web environment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第6期10卷 843-857页

作者： Jinhyung KIM Dongwon jeong Doo-kwon BAIK Department of Computer Science and Engineering Korea University Department of Informatics and Statistics Kunsan National University

With the rapid growth of the Web, the volume of information on the Web is increasing exponentially. However, information on the current Web is only understandable to humans, and this makes precise information retrieval difficult. To solve this problem, the Semantic Web was proposed. We must use ontology languages that can assign data the semantics for realizing the Semantic Web. One of the representative ontology languages is the Web ontology language OWL, adopted as a recommen-dation by the World-Wide Web Consortium (W3C). OWL includes hierarchical structural information between classes or prop-erties. Therefore, an efficient OWL storage model that considers a hierarchical structure for effective information retrieval on the Semantic Web is required. In this paper we suggest an XPath-based OWL storage (XPOS) model, which includes hierarchical information between classes or properties in XPath form, and enables intuitive and effective information retrieval. Also, we show the comparative evaluation results for the performance of the XPOS model, Sesame, and the XML file system-based storage (XFSS) model, in terms of query processing and ontology updating.

关键词： XPath Web ontology language Hierarchical structure Ontology storage Semantic Web

Statistical estimations for Plasmodium vivax malaria in South Korea

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Asian Pacific Journal of Tropical Medicine 2015年第3期8卷 169-175页

作者： Youngsaeng Lee Hyeongap Jang jeong Ae Rhee jeong-Soo Park Department of Statistics Chonnam National University JW LEE Center for Global Medicine College of MedicineSeoul National University Department of Preventive Medicine Chonnam National University

Objective:To calculate the numbers of weekly infections and prevalence of malaria,and to predict future trend of malaria incidences in South ***:Weekly incidences of malaria for 13 years from the period 2001-2013 in South Korea were *** backcalculation equations were used with incubation period *** maximum likelihood estimation for Poisson model was also *** confidence intervals of the estimates were obtained by a bootstrap method.A regression model for time series of malaria incidences over13 years was fitted by the non-linear least squares method,and used to predict ***:The estimated infection curve is narrower and more concentrated in the summer than in the incidence *** started around the 19 th week and was over around the41 st *** maximum weekly infection 110 was obtained at the 29 th *** prevalence at the first week was around 496 persons,the minimum number was 366 at 22 nd week,and the maximum prevalence was 648 at 34 th *** drops in late spring with people that falling ill and had had long incubation periods and rose in the summer with new *** future forecast based on the regression model was that an increase at year 2014 compared to 2013 may reach a peak(at maximum about 70 weekly cases) at year *** a decreasing trend after ***:This work shows that back-calculation methods could work well in estimating the infection rates and the prevalence of *** obtained results can be useful in establishing an efficient preventive program for malaria *** method presented here can be used in other countries where incidence data and incubation period are available.

关键词： Back calculation Incidence Incubation period Infection Poisson model Prevalence Regression model

A study on flow fields and performance of water wheel turbine using experimental and numerical analyses

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Science China(Technological Sciences) 2018年第3期61卷 464-474页

作者： NGUYEN Manh Hung jeong Haechang YANG Changjo Graduate School Division of Marine Engineering Mokpo National Maritime University Department of Marine Engineering Mokpo National Maritime University

In this paper, an analysis of the performance and flow fields of water wheel turbines for tidal energy extraction is carried out using experimental and numerical methods. The purpose of this work is to develop a water turbine suitable for sites, where fast and shallow surface flows are available, such as rivers or tidal currents. For both methods, the water wheel turbine is tested over a range of tip speed ratios with a differing number of rotor blades, ranging between three and twelve. The results indicate that the numerical simulation shows agreement with the experiment in most cases. Also, the water wheel turbine operates effectively at a range of small tip-speed ratios, where the highest turbine efficiency is produced. Under the same working conditions, the turbines using between six and nine blades generate a greater efficiency and cause lesser reverse flows than others when submerged in water. In contrast, the 3-bladed turbine is the least efficient design as it produces the lowest amount of energy and causes intense vibrations and noises. These noises are a result of a collision between the incoming flow of the channel and the wheel blades during the experimentation, especially at high load conditions. By adding more blades, the torque generated is improved considerably; however, the upstream and downstream depths of the turbine, in this case, are also elevated ***, in the inlet region, the 3-bladed and 6-bladed turbines have a smaller shock loss and a lower resistance to the main flow from the inlet than the others. Meanwhile, it is found that the flow in the outlet region on the turbines with between nine and twelve blades is in the opposite direction to the wheel's rotation, significantly obstructing the main flow from the inlet.

关键词： water wheel tidal energy tip speed ratio the number of blades

Influence of the molecular structure of metal-phthalocyanine on electrocatalytic reactions

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Science China Materials 2022年第12期65卷 3324-3333页

作者： Da Sol jeong Hyeon Suk Shin Jieun Yang Department of Chemistry Ulsan National Institute of Science and Technology(UNIST)50 UNIST-gilUlsan 44919Republic of Korea Department of Chemistry and Research Institute of Basic Sciences Kyung Hee University26 Kyungheedae-roDongdaemun-guSeoul 02447Republic of Korea

The demand for new catalysts for renewable energy production has become *** an alternative to metal catalysts for electrocatalysis to produce energy sources,metal-phthalocyanine(MPc)electrocatalysts have shown *** physicochemical and electrochemical properties depend on the chemical structure of the MPc and the central metal *** reviews of MPcs focused on their electrochemical performance in specific catalytic reactions,such as oxygen reduction reaction and CO_(2)reduction ***,understanding the structure of MPcs in depth is important,since their electrochemical catalytic activity is affected by structural modifications of ***,this minireview focuses on how the molecular structure of MPcs affects electrochemical catalysis.

关键词： metal-phthalocyanine oxygen reduction reaction carbon dioxide reduction reaction hydrogen evolution reaction oxygen evolution reaction electrocatalytic activities

Microstructure tailoring of Al_(0.5)CoCrFeMnNi to achieve high strength and high uniform strain using severe plastic deformation and an annealing treatment

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Journal of Materials Science & Technology 2021年第12期71卷 228-240页

作者： H.T.jeong W.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

Ultrafine-grained alloys fabricated by severe plastic deformation(SPD)have high strength but often poor uniform *** via high-ratio differential speed rolling(HRDSR)followed by an annealing treatment was applied to Al_(0.5)CoCrFeMnNi to design the microstructure from which both high strength and high uniform strain can be *** optimized microstructure was composed of an ultrafine-grained FCC matrix(1.7-2μm)with a high fraction of high-angle grain boundaries(61%-66%)and ultrafine BCC particles(with a size of 0.6-1μm and a volume fraction of8%-9.3%)distributed uniformly at the grain boundaries of the FCC *** the severely plastically deformed microstructure,the nucleation kinetics of the BCC phase was *** static recrystallization(CSRX)took place during the annealing process at 1273 *** of the BCC phase particles occurring concurrently with CSRX effectively retarded the grain growth of the FCC *** precipitation of the hard and brittleσphase was,however,*** annealed sample processed by HRDSR with the optimized microstructure exhibited a high tensile strength of over 1 GPa with a good uniform elongation of 14%-20%.These tensile properties are comparable to those of transformation-induced plasticity *** mechanisms of the severely plastically deformed alloy before and after annealing were identified,and each strengthening mechanism contribution was *** calculated results matched well with the experimental results.

关键词： High entropy alloys Severe plastic deformation Uniform ductility High strength Dual phase Annealing

Grain size and temperature effect on the tensile behavior and deformation mechanisms of non-equiatomic Fe(41)Mn(25)Ni(24)Co8Cr2high entropy alloy

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Journal of Materials Science & Technology 2020年第7期42卷 190-202页

作者： H.T.jeong W.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul121-791Republic of Korea

The effect of the grain size on the tensile properties and deformation mechanisms of a nonequiatomic Fe(41)Mn(25)Ni(24)Co8 Cr2 high-entropy alloy was studied in the temperature range between 298 and 1173 K by preparing the samples with three different grain sizes through severe plastic deformation and subsequent annealing:ultrafine(sub)grain size(≤0.5μm),8.1μm and 590.2μ*** the temperature between 298 and773 K,the material with the large grain size of 590.2μm exhibited the largest tensile ductility(57%-82%)due to its high strain hardening associated with mechanical twinning,but it exhibited the lowest strength due to its large grain *** material with the ultrafine(sub)grain size exhibited the lowest tensile ductility(3%-7%)due to a greatly reduced strain hardening ability after severe plastic deformation,but it exhibited the highest strength due to the dislocation strengthening and grain refinement *** tensile testing at temperatures above 973 K,recrystallization occurred in the material with the ultrafine(sub)grains during the sample heating and holding stage,leading to the formation of fine and equiaxed grains with the sizes of 6.8-13.5μ*** deformation behavior of the Fe(41)Mn(25)Ni(24)Co8 Cr2 with different grain sizes in the high temperature range between 973 and 1173 K,where pseudosteady-state flow was attained in the stress-strain curves,could be explained by considering the simultaneous contribution of grain boundary sliding and dislocation-climb creep to total plastic *** activation energies for plastic flow for the materials with different grain sizes were similar as^199 kJ/*** predicting the deformation mechanism,it was important to consider the change in grain size by rapid grain growth or recrystallization during the sample heating and holding stage because grain boundary sliding is a grain-size-dependent deformation *** sample with the ultrafine(sub)grains exhibited the large tensile elongations of 30%-85%due to it

关键词： High entropy alloys Grain size High temperature deformation mechanism Tensile behavior Grain boundary sliding

Strong association of regulatory single nucleotide polymorphisms (SNPs) of the IFITM3 gene with influenza H1N1 2009 pandemic virus infection

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Cellular & Molecular Immunology 2020年第6期17卷 662-664页

作者： Yong-Chan Kim Min-Ju jeong Byung-Hoon jeong Korea Zoonosis Research Institute Chonbuk National UniversityIksanJeonbuk 54531Republic of Korea Department of Bioactive Material Sciences Chonbuk National UniversityJeonjuJeonbuk 54896Republic of Korea

The IFITM3 gene is classified as a member of the small interferonstimulated genes(ISGs)and plays a paramount role in defense against enveloped viruses,including influenza A viruses.1–6 Previous studies have reported that the rs12252 SNP,which is located in the open reading frame(ORF)of the IFITM3 gene,impacts the splicing procedure of protein production,which makes a truncated form of the IFITM3 protein and lowers its antiviral capacity.7–9 In addition,the rs34481144 SNP genotype affects the transcriptional regulation of the IFITM3 gene and IFITM3-neighboring genes and has a potent association with the clinical results of the H1N1 influenza 2009 pandemic in three human cohorts.10 Because several studies have reported that polymorphism of the IFITM3 gene is crucial in the host immune response,fine mapping of and extracting disease-associated SNPs from the human IFITM3 gene are important baseline studies necessary to understand how the IFITM3 protein functions in innate immunity.

关键词： IFITM3 influenza H1N1

Effect of roll speed ratio on the texture and microstructural evolution of an FCC high-entropy alloy during differential speed rolling

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Journal of Materials Science & Technology 2022年第16期111卷 152-166页

作者： H.T.jeong W.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

A very coarse-grained(335μm)Fe_(41)Mn_(25)Ni_(24)Co_(8)Cr_(2)high-entropy alloy with a single FCC phase was cold rolling to a 80%reduction in thickness using the differential speed rolling technique with various speed ratios(SRs)ranging between 1 and *** the SR was increased,the volume fraction of the region of high-density micro-shear bands increased to accommodate the higher shear *** SR=4,the entire thickness of the sheet was covered with micro-shear bands,and ultrafine(sub)grains with a size of1.4μm were uniformly formed along the shear bands.A continuous dynamic recrystallization(CDRX)mechanism occurred during rolling,and a higher SR accelerated the CDRX *** conventional rolling(at SR=1),a brass{110}orientation texture with minor components of S{123}and Cu{112}orientations *** higher SRs,shear texture developed as the main type,while the development of rolling texture was *** microstructure at SR=4 obtained after annealing at973 K showed a fully recrystallized microstructure composed of a five times smaller grain size(4μm)with a higher intensity ofγfiber texture compared with that prepared by conventional *** samples processed with high SRs exhibited better tensile properties compared with the conventionally rolled sample in terms of strength and ductility after *** current results demonstrate that by using differential speed rolling with a high SR,one can achieve a significantly finer and more homogeneous microstructure,stronger shear texture,and superior tensile mechanical properties for an FCC high-entropy alloy compared to that obtained by conventional *** strength of the as-rolled and annealed samples was quantitatively explained by considering the contribution of grain size and dislocation density to strengthening.

关键词： High entropy alloys Differential speed rolling Texture Grain refinement Strength Severe plastic deformation

Hydrogen sulfide controls peripheral nerve degeneration and regeneration:a novel therapeutic strategy for peripheral demyelinating disorders or nerve degenerative diseases

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Neural Regeneration Research 2014年第24期9卷 2119-2121页

作者： Junyang Jung Na Young jeong Department of Anatomy and Neurobiology School of Medicine Biomedical Science Institution Kyung Hee University Department of Anatomy and Cell Biology College of Medicine Dong-A University

After peripheral nerve injury, the process of Wallerian degeneration is initiated in the distal stump of injured nerves. Wallerian degeneration in peripheral nerves involves axonal degeneration and degradation of the myelin sheath in Schwann cells. This provides the necessary conditions for axonal regeneration and remyelination. After nerve injury, macrophages are also recruited to the distal nerve stump and, together with Schwann cells, play a role in the clearance of myelin debris.

关键词： Hydrogen sulfide controls peripheral nerve degeneration and regeneration Figure