• 한국항해항만학회지
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• 제43권2호
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• pp.134-141
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• 2019

The objective of this study was to establish whether global macroeconomic indicators affect the profitability of Korean shipping companies by using panel regression analysis. OROA (operating return on assets) and ROA (ratio of net profit to assets) were selected as proxy variables for profitability. OROA and ROA were used as dependent variables. The world GDP growth rate, interest rate, exchange rate, stock index, bunker price, freight, demand and supply of the world shipping market were set as independent variables. The size of the firm was added to the control variable. For small-sized firms, OROA was not affect by macroeconomic indicators. However, ROA was affected by variables such as interest rates, bunker prices, and size of firms. For medium-sized firms, OROA was affected by demand, supply, GDP, freight, and asset variables. However, macroeconomic indicators did not affect ROA. For large-sized firms, freight, GDP, and stock index (SCI; Shanghai Composite Index) have an effect on OROA. ROA was analyzed to be influenced by bunker price and SCI.

• Structural Engineering and Mechanics
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• 제77권4호
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• pp.559-569
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• 2021

This study was conducted to investigate the residual bearing capacity of steel-concrete composite beams under high-cycle fatigue loading through experiments and theoretical analysis. Six test beams with stud connectors were designed and fabricated for static, complete fatigue, and partial fatigue tests. The failure modes and the degradation of several mechanical performance indicators of the composite beams under high-cycle fatigue loading were analyzed. A calculation method for the residual bearing capacity of the composite beams after certain quantities of cyclic loading cycles was established by introducing nonlinear fatigue damage models for concrete, steel beam, and shear connectors beginning with the material residual strength attenuation process. The results show that the failure mode of the composite beams under the given fatigue load appears to be primarily affected by the number of cycles. As the number of fatigue loadings increases, the failure mode transforms from mid-span concrete crushing to stud cutting. The bearing capacity of a 3.0-m span composite beam after two million fatigue cycles is degraded by 30.7% due to premature failure of the stud. The calculated values of the residual bearing capacity method of the composite beam established in this paper agree well with the test values, which indicates that the model is feasibly applicable.

• 지역과문화
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• 제7권2호
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• pp.173-202
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• 2020

이 연구는 가족관계와 지역사회 환경의 관계를 살피고, 가족을 둘러싼 지역 환경을 객관적으로 비교함으로써 지역의 가족친화성 제고방안을 제시하고자 한다. 이를 위해 가족관계 만족도에 영향을 주는 사회문화적, 경제적 차원의 영역을 검토하였으며, 특히 지역사회지표로 개발된 한국가족행복종합지수(이하, 종합지수)를 활용하여, 지역별 종합지수 변화 추이를 분석하였다. 이 연구에서 활용한 종합지수는 국가통계포털의 「e-지방지표」에서 공시한 지역사회지표를 활용하였으며, 이 변수들은 가족관계만족도와 연관된다. 이에 본 연구에서는 가족행복종합지수의 7개 영역(인구가족, 건강문화, 교육, 소득소비, 고용노동, 주거 교통, 환경 및 사회통합)을 비교하여 10년간 추이를 검토하였다. 연구결과, 2008년도부터 2018년도까지 종합지수의 전국 평균점수는 점점 상승하고 있었다. 전반적으로 가족관계만족도에 영향을 주는 지역사회환경 역시 개선되고 있다고 볼 수 있다. 상위레벨에 속한 지역은 전남, 강원, 충남, 전북, 경북으로 비수도권 및 농촌권역이었다. 하위레벨에 속한 지역은 서울, 부산, 대구, 인천, 광주로 모두 특광역시로 대도시권역이다. 전반적으로 하위레벨에 속한 지역들은 인구 밀집 및 과밀도에 비해 관련 물리적 인프라가 충분하지 않았으며 조금씩 개선하고 있었으나, 지역민의 욕구를 반영하고 삶의 질을 개선할 수 있을 만큼은 아니었다. 향후 가족관계의 질을 향상할 수 있는 각 지역별 맞춤형 정책 마련을 위해서 보다 정기적이고 보완된 지표 개발이 필요하다. 또한 사회적 재난으로 인한 사회경제적 위기가 각 영역별, 지역별 미친 영향과 향후 변화추이를 지속적으로 검토할 필요가 있음을 제언하였다.

• 한국의료질향상학회지
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• 제7권2호
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• pp.204-216
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• 2000

Background : There has been a concern that the quality of care provided to end-stage renal disease (ESRD) patients in the United States may not be as good as recommended. This paper illustrates a composite measure to assess, the quality of care received by ESRD patients undergoing in-center hemodialysis by incorporating outcomes for 4 major treatment areas. The 4 treatment areas are: dialysis treatments, anemia control, nutritional management, and blood pressure control. Methods : The major data source for the study was the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Study Wave 1 (DMMS-1) d Sixteen categories of a composite quality indicator were constructed by combining 4 dichotomous variables (16=2*2*2*2). representing the optimal vs. less than optimal level of outcome for each of the 4 treatment outcome measure respectively. Optimal outcome level for each treatment area was defined based on the recommendation from the National Kidney Foundation: (a) delivered dialysis doses (Kt/V) ${\geq}$ 1.2; (b) hematocrit level ${\geq}$ 30%; (c) serum albumin concentration ${\geq}$ 3.8g/dl ; and (d) blood pressure of <140 / <90mmHg. The 16 quality indicator were ranked according to their relative quality weights, which were estimated from its association with the relative risk of survival, adjusting for patient's baseline severity and dialysis facility characteristics. Results : Out of the entire sample of 2,179 patients, only 229 (10%) meet th recommended outcome levels for all 4 treatment areas. Overall, the study patients were distributed evenly over the 16 quality indicators, indicating a great variation in the quality of ESRD care. It appears that the rank of the 16 quality-indicators is driven by serum albumin concentration, suggesting that serum albumin concentration may be the most powerful predictor of ESRD patient survival among the 4 outcome measures. Conclusion : The developed quality indicator has the advantage of describin a range of care for dialysis patients and thus providing a more complete picture of care as compared to previous studies that have focused on only single or few components of the ESRD care.

• Structural Engineering and Mechanics
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• 제82권3호
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• pp.343-354
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• 2022

An understanding of the mechanism of concrete girders repaired with CFRP plates and its influence on the dynamic parameters is presented in this paper. Dynamic parameters are governed by the relationship with the physical properties of concrete girders and CFRP plates as well as the adhesive layer between them. A brief explanation of the mechanism of the composite action of concrete girders repaired with CFRP is also given in this paper. Experimental work was carried out to validate the theory of the composite action. The results show a decrease in the modal parameters of CFRP repaired girders that were turned over during the repair procedure, which contrasts with the proven static-based results that CFRP plates increase the stiffness of repaired girders. The composite action theory has explained the results based on the tension and compression forces' growth at the adhesive layer between the CFRP plates and girder surface during the repair procedure. Other girders were prepared and repaired without turning over in order to avoid tension and compression forces at the adhesive layer. The experimental results show an increase in the dynamic parameters of CFRP repaired girders that were not turned over during the repair procedure, which aligns with the static-based results. The study concludes that the dynamic parameters are excellent indicators for the assessment of CFRP repaired concrete girders. The study also suggests that researchers should not turn over damaged concrete girders to repair them with CFRP plates if they intend to study the dynamic parameters, in order to avoid the proposed composite action effect on modal parameters.

• 한국도로학회논문집
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• 제11권3호
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• pp.111-120
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• 2009

본 논문에서는 도로포장의 성능개선을 유도하기 위한 제도적 수단인 공사비 차등지급규정(지불규정)을 제시하고 이를 고속도로 아스팔트 포장 공사에 처음으로 적용한 결과를 다루고 있다. 지불규정을 적용하기 위한 단위구간(lot)은 덧씌우기 포장의 일평균 시공연장으로 정의하였다. 단위구간은 다시 포장의 초기상태 평가를 위한 최소 단위인 세부단위구간(sublot)으로 나누었으며, 세부단위구간에서 측정한 품질항목의 평균과 표준편차를 이용하여 단위구간을 대표하는 품질항목별 지불계수(pay factor)를 산정하였다. 마지막으로, 각각의 품질항목이 포장의 중장기 공용성에 미치는 상대적 영향을 고려하여 합성지불계수를 결정하였다. 본 연구에서 제시한 지불규정은 2008년에 한국도로공사 6개 지역본부(충청, 호남, 경북, 경남, 경인, 강원)에서 시행된 아스팔트 덧씌우기 포장공사에 적용하였으며, 이 과정에서 제기된 고려사항 및 문제점을 정리하였다. 결론적으로, 품질항목에 대한 평가결과가 품질관리한계를 만족하는 경우에는 기존 공사비 대비 최대 50% 가까이 인센티브 지급이 가능함을 알 수 있었다. 반면에, 다짐도와 같은 주요 성능관련 품질이 낮을 경우 기존 공사비 대비 최대 10% 가까이 공사비 감액도 있을 수 있음을 확인하였다.

• 대한교통학회지
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• 제27권1호
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• pp.191-200
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• 2009

본 연구는 현재 보행교통류율, 보행자지체 등의 정량적인 지표만을 고려하고 있는 기존 보행자 이동공간 서비스수준(Level of Service) 평가의 한계를 극복하고, 보행자의 이동공간(보도 및 횡단보도)만족도에 영향을 미치는 정성적 요인을 반영하여 보행자의 실질적인 서비스 질(QOS : duality of Service)을 측정할 수 있는 통합적 지표를 개발하는 것이 목적이다. 연구를 위한 기초자료 수집은 설문조사를 이용하였고, 통합지표 개발을 위해 계층분석법(AHP)과 네트워크분석법(ANP)을 활용하였다. 주요 연구결과는 첫째, 보행자가 서비스수준을 판단할 경우 중복성을 느끼고 있음을 알 수 있어, 네트워크분석법에 의한 지표를 적용하는 것이 적절함을 확인하였다. 둘째, 보행자 행태, 유지관리, 보행경관 및 환경과 같은 정성적인 요인을 고려해야 한다는 것을 알 수 있었으며 특히 주거지역에서 정성적인 요인의 중요도가 높은 것을 알 수 있었다. 향후 실질적인 보행자 서비스 질을 평가하기 위해서는 정량적인 지표는 물론 정성적인 지표를 고려하는 것이 적절할 것이라 판단된다.

• 한국병원경영학회지
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• 제25권3호
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• pp.78-86
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• 2020

Purposes: This study purposed to identify factors influencing the composite quality score from the quality assessment program for long-term care hospitals Methodology: The study variables was obtained from HIRA(Health Insurance Review and Assessment Service): the composite quality scores and hospital variables such as number of doctors, nurses, beds, medical technicians, medical equipments, administrative region, ownerships from 3rd (2010) to 7th (2018) quality assessment program. National Statistical Portal(www.kosis.go.kr) provided the number of senior citizens aged over 65 in city·county·district area. SAS 9.4 was used for the data processing and used to analyze the data. Findings: The results showed that composite quality score increased past 9 years. Hospital variables such as number of doctor, nurse, medical technicians, bed and public hospitals had significant positive relationship with the composite quality score. Administrative region(district) showed higher scores compare to that of city. Compare to the score of quality assessment year(2010), as the assessment year move to 2012, 2013, 2015, 2018, results showed higher significant positive coefficients. Practical Implication: Continuously improve the performance of long-term care hospitals, current quality assessment program are needed to update their system such as adopting indicators measuring the service process, or compensating the cost for quality assessment program. It will enable to provide more reasonable and accurate performance assessment scores.

• Journal of Microbiology and Biotechnology
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• 제32권3호
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• pp.387-395
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• 2022

Deciphering the metabolites of human diseases is an important objective of biomedical research. Here, we aimed to capture the core metabolites of Fanconi anemia (FA) using the bioinformatics method of a multi-omics composite network. Based on the assumption that metabolite levels can directly mirror the physiological state of the human body, we used a multi-omics composite network that integrates six types of interactions in humans (gene-gene, disease phenotype-phenotype, disease-related metabolite-metabolite, gene-phenotype, gene-metabolite, and metabolite-phenotype) to procure the core metabolites of FA. This method is applicable in predicting and prioritizing disease candidate metabolites and is effective in a network without known disease metabolites. In this report, we first singled out the differentially expressed genes upon different groups that were related with FA and then constructed the multi-omics composite network of FA by integrating the aforementioned six networks. Ultimately, we utilized random walk with restart (RWR) to screen the prioritized candidate metabolites of FA, and meanwhile the co-expression gene network of FA was also obtained. As a result, the top 5 metabolites of FA were tenormin (TN), guanosine 5'-triphosphate, guanosine 5'-diphosphate, triphosadenine (DCF) and adenosine 5'-diphosphate, all of which were reported to have a direct or indirect relationship with FA. Furthermore, the top 5 co-expressed genes were CASP3, BCL2, HSPD1, RAF1 and MMP9. By prioritizing the metabolites, the multi-omics composite network may provide us with additional indicators closely linked to FA.

• Journal of Preventive Medicine and Public Health
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• 제52권5호
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• pp.281-291
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• 2019

Objectives: The validity of instruments measuring socioeconomic position (SEP) has been a major area of concern in research on cardiovascular health disparities. The purpose of this systematic review is to identify the current status of the methods used to measure SEP in research on cardiovascular health disparities in Korea and to provide directions for future research. Methods: Relevant articles were obtained through electronic database searches with manual searches of reference lists and no restriction on the date of publication. SEP indicators were categorized into compositional, contextual, composite, and life-course measures. Results: Forty-eight studies published from 2003 to 2018 satisfied the review criteria. Studies utilizing compositional measures mainly relied on a limited number of SEP parameters. In addition, these measures hardly addressed the time-varying and subjective features of SEP. Finding valid contextual measures at the organizational, community, and societal levels that are appropriate to Korea's context remains a challenge, and these are rarely modeled simultaneously. Studies have rarely focused on composite and life-course measures. Conclusions: Future studies should develop and utilize valid compositional and contextual measures and appraise social patterns that vary across time, place, and culture using such measures. Studies should also consider multilevel influences, adding a focus on the interactions between different levels of intertwined SEP factors to advance the design of research. More attention should be given to composite and life-course measures.