해후를 위하여

류재홍 수필미학 2024 수필미학 Vol.45 No.-

희소 행렬벡터 곱셈의 새로운 부하 균형 방법과 하이퍼규브상의 인공 신경 회로망의 효과적인 매핑

류재홍 여수대학교 1997 論文集 Vol.11 No.2

This paper suggests an effective solution to the load balancing problem among the processing nodes during the mapping of partially connected artificial neural networks onto hypercube interconnection network parallel processing systems. Two new methods of partitioning of the elements of matrix are introduced for the effective execution of matrix vector multiplication on torus architecture. The first common step is the 2 way sorting procedure of rows and columns using the counts of nonzero elements in the rows and the columns respectively for the maximum load balancing performance. The next step is the real location procedure from the maximum unbalanced load distribution to the minimum one among the processing nodes.

도로터널 제트팬 모형 실험

류재홍,유용호,김진,Ryu, Jae-Hong,Yoo, Young-Ho,Kim, Jin 대한설비공학회 2003 설비공학 논문집 Vol.15 No.8

As tunnel ventilation has recently been playing a major role in the tunnel construction and maintenance, longitudinal ventilation systems with jet fans have been utilized a great deal because they are economical and effective. However, due to the length of tunnels and heavy traffic, it is hard to take the field measurements. In this study, therefore, the computer simulation and the model experiment of producing a wind tunnel were carried out simultaneously and the results were compared. The ultimate objective of this research was to interpret the air flow pattern inside the tunnel with a jet-fan was set up, and to offer the useful data for jet-fan installation and operation. The experiment was carried out with varying the jet-fan diameters, location of installation, the discharge velocity. Result showed that as the initial static pressure came up with the negative pressure, the tunnel air flowed into the inside of tunnel from outside due to the entrainment-effect and the backflow-phenomenon by separation-effect was observed in the lower half part of the tunnel. As the jet-fan was getting closer to the tunnel wall, the entrainment-effect caused by the interaction with the wall was increased; however, the mixing distance and irregular flow section became longer, and also the air pressure loss generated by wall friction was large.

DO 미터를 이용한 탐구중심 물 환경교육 프로그램 개발- 용존산소 측정 활동 -

류재홍,이두곤 한국환경교육학회 2006 環境 敎育 Vol.19 No.2

Inquiry has great value in environmental education(EE). Being able to see the world environmentally through 'inquiry-based environmental education' can be an important value and goal of EE. In this study, we intended to develop an EE program of measuring activity of dissolved oxygen(DO), based on the theory of 'inquiry-based EE'. Especially, we recognized the potential that DO meter can be used in 'inquiry-based EE', and we tried to develop a model of inquiry-based EE using DO meter. As a result of this research, we present specific models of inquiry-based EE about how to perform measuring activity of DO and how to use the DO meter in laboratories and streams from the perspective of inquiry of water environment.In the process of program development, we considered organization of the inquiry process, use of concept and knowledge, scientific inquiry and insightful inquiry, integration, sustainability, content components of 'Environmental Studies for EE', developmental level and in-

Clinical Significance of Non-Alcoholic Fatty Liver Disease as a Risk Factor for Prehypertension

류재홍,함우택,최중명,강민아,안소희,이종근,신호철,박성근 대한의학회 2014 Journal of Korean medical science Vol.29 No.7

Previous epidemiologic studies have shown the clinical association between non-alcoholicfatty liver disease (NAFLD) and cardiovascular disease (CVD). However, there is only limitedinformation about the effect of NAFLD on the development of hypertension. Accordingly,we investigated the clinical association between NAFLD and prehypertension. A prospectivecohort study was conducted on the 11,350 Korean men without prehypertension for 5 yr. The incidences of prehypertension were evaluated, and Cox proportional hazard model wasused to measure the hazard ratios (HRs) for the development of prehypertension accordingto the degree of NAFLD (normal, mild, moderate to severe). The incidence of prehypertensionincreased according to NAFLD states (normal: 55.5%, mild: 63.7%, moderate to severe:70.3%, P < 0.001). Even after adjusting for multiple covariates, the HRs (95% confidenceinterval) for prehypertension were higher in the mild group (1.18; 1.07-1.31) and moderateto severe group (1.62; 1.21-2.17), compared to normal group, respectively (P for trend< 0.001). The development of prehypertension is more potentially associated with themore progressive NAFLD than normal and milder state. These findings suggest the clinicalsignificance of NAFLD as one of risk factors for prehypertension.

사회네트워크 분석을 활용한 비즈니스 모델 지식구조 분석

류재홍,최진호 한국지식경영학회 2018 지식경영연구 Vol.19 No.2

Business environment is shifting from industrial economy to knowledge based economy. Enterprises go through numerous trials for successful management in changing environment. Along with trial tests, research area has been growing simultaneously. Unlike initial research which focused on basic concepts such as: form of business model and success points. Current research emphasizes on actualization of business that enterprises plan, which brought academic research with perplex form of knowledge structure. On the other hand, there is limitation in understanding business model systematically due to preceding research primarily centered on analyzing definition and case study. In order to analyze knowledge structure, this study utilized social network analysis based on “relationship”. For the analysis, 13,412 keywords were extracted from 36years worth of article or research related to business model stored in SCOPUS database. From the analysis, it was shown core research subject was INNOVATION and the number of co-authors has increased due to the academic diversity. Business model research is divided into five sub-categories (E-commerce, SMEs, sustainability, open-source, and e-book). Through cognitive map analysis on each of research characteristics of sub-category, it has shown that E-commerce, SMEs, sustainability, and open-source are core categories.

후유증

류재홍 수필미학 2018 수필미학 Vol.19 No.-

가슴이 따뜻한 사람 외

류재홍 수필미학 2019 수필미학 Vol.25 No.-

The Risk for Insulin Resistance according to the Degree of Non-Alcoholic Fatty Liver Disease in Korean Men

류재홍,홍현표,박성근,함우택,정주연 대한의학회 2016 Journal of Korean medical science Vol.31 No.11

Insulin resistance (IR) plays a significant role in the development and progression of non-alcoholic fatty liver disease (NAFLD). However, the natural course of insulin sensitivity under NAFLD remained unclear. Accordingly, this study was designed to investigate the effect of NAFLD on insulin resistance. A total of 20,628 Korean men without homeostasis model assessment of insulin resistance (HOMA-IR < 2.7) were followed-up for 5 years. They were serially checked for HOMA-IR to monitor the development of IR (HOMA-IR ≥ 2.7). The incidence rate of IR increased according to the degree of NAFLD (normal: 11.6%, mild: 28.8%, moderate to severe: 40.5%, P < 0.001). Cox proportional hazards model showed that HRs (95% CI) for IR increased proportionally to the degree of NAFLD (mild: 1.19 [1.02–1.39], moderate to severe: 1.32 [1.08–1.57]). IR was more potentially associated with the more progressive NAFLD than normal and milder state. In addition, NAFLD was the independent risk factor of the development of IR. These results suggest the potential availability of NAFLD as a predictor of IR.

키워드 네트워크 분석을 통한 지식구조 변화 연구 :비즈니스 모델 연구를 중심으로

류재홍,최진호 한국IT서비스학회 2018 한국IT서비스학회지 Vol.17 No.2

The business models has a great impact on the successful management of enterprises. Business environment has been shifting from industrial economy to knowledge-based economy. Enterprises go through numerous trials for successful management in the changing environment. Along with trial tests, research areas have been growing simultaneously. Although many researches have been conducted with regard to business models, it is very insufficient to systematically analyze the knowledge flow of research. Accordingly, successive researchers who want to study the business model may find it difficult to establish the orientation of future application research based on understanding the process of changing the knowledge structure that have accumulated so far. This study is intended to determine the current state of the business model research and to understand the process of knowledge structure changes in keywords that appear in 2,667 business model articles in the SCOPUS database. Identifying the knowledge structure has been completed through social network analysis, a methodology based on the ‘relationship', and the changes in the knowledge structure were identified by classifying them into four different periods. The analysis showed that, first, the number of business model co-author increases over time with the need for academic diversity. Second, the ‘innovation' keyword has the biggest center in the network, and over time, the lower-rank keyword which was in the former period has emerged as the top-rank keyword. Third, the cohesiveness group decreased from 12 before 2000 to 5 in 2015 and also the modularity decreased as well. Finally, examining characteristics of study area through a cognitive map showed that the relationships between domains increased gradually over time. The study has provided a systematic basis for understanding the current state of the business model research and the process of changing knowledge structure. In addition, considering that no research has ever systematically analyzed the knowledge structure accumulated by individual researches, it is considered as a significant study.