• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.800-809
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• 2007

Current payment methods have many faults which are detrimental to the formation and completion of a project. This includes the use of unfair payment terms, pricing strategies and payment mechanisms between the contracting parties. This resulted in being criticised and remain in doubt, the use of current payment methods to reward good contractors and to distinguish poorly performed construction firms. In order to have an insight into this issue, a structured survey was conducted amongst UK construction practitioners. It was found that traditional pricing methods (i.e. lump sum and unit price), payment methods (i.e. interim valuation) and retention still dominate current practice. The empirical findings show that there are significant differences in the use of pricing and payment methods (when making and receiving payments) in construction. Significant differences also found in the factors affecting the choice of pricing methods when making (and receiving) construction payments. The paper concludes with analysis of the findings and future direction of research in payment systems is also provided.

• Nuclear Engineering and Technology
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• 제52권2호
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• pp.230-237
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• 2020

In this part, an implicit time dependent solution is presented for the Boltzmann transport equation discretized by the analytic coarse mesh finite difference method (ACMFD) over the spatial domain as well as the simplified P₃ (SP₃) for the angular variable. In the first part of this work we proposed a SP₃-ACMFD approach to solve the static eigenvalue equations which provide the initial conditions for temp dependent equations. Having solved the 3D multi-group SP₃-ACMFD static equations, an implicit approach is resorted to ensure stability of time steps. An exponential behavior is assumed in transverse integrated equations to establish a relationship between flux moments and currents. Also, analytic integration is benefited for the time-dependent solution of precursor concentration equations. Finally, a multi-channel one-phase thermal hydraulic model is coupled to the proposed methodology. Transient equations are then solved at each step using the GMRES technique. To show the sufficiency of proposed transient SP₃-ACMFD approximation for a full core analysis, a comparison is made using transport peers as the reference. To further demonstrate superiority, results are compared with a 3D multi-group transient diffusion solver developed as a byproduct of this work. Outcomes confirm that the idea can be considered as an economic interim approach which is superior to the diffusion approximation, and comparable with transport in results.

• 한국환경과학회지
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• 제25권7호
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• pp.1029-1042
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• 2016

The initial and boundary conditions are important factors in regional chemical transport modeling systems. The method of generating the chemical boundary conditions for regional air quality models tends to be different from the dynamically varying boundary conditions in global chemical transport models. In this study, the impact of real time Copernicus atmosphere monitoring service (CAMS) re-analysis data from the modeling atmospheric composition and climate project interim implementation (MACC) on the regional air quality in the Korean Peninsula was carried out using the community multi-scale air quality modeling system (CMAQ). A comparison between conventional global data and CAMS for numerical assessments was also conducted. Although the horizontal resolution of the CAMS re-analysis data is not higher than the conventionally provided data, the simulated particulate matter (PM) concentrations with boundary conditions for CAMS re-analysis is more reasonable than any other data, and the estimation accuracy over the entire Korean peninsula, including the Seoul and Daegu metropolitan areas, was improved. Although an inland area such as the Daegu metropolitan area often has large uncertainty in PM prediction, the level of improvement in the prediction for the Daegu metropolitan area is higher than in the coastal area of the western part of the Korean peninsula.

• Journal of Gastric Cancer
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• 제17권1호
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• pp.21-32
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• 2017

Purpose: Perioperative chemotherapy improves survival outcomes in locally advanced (LA) gastric cancer. Materials and Methods: We retrospectively analyzed patients with LA gastric cancer who were offered perioperative chemotherapy consisting of epirubicin, oxaliplatin, and capecitabine (EOX) from May 2013 to December 2015 at Tata Memorial Hospital in Mumbai. Results: Among the 268 consecutive patients in our study, 260 patients (97.0%) completed neoadjuvant chemotherapy, 200 patients (74.6%) underwent D2 lymphadenectomy, and 178 patients (66.4%) completed adjuvant chemotherapy. The median follow-up period was 17 months. For the entire cohort, the median overall survival (OS), 3-year OS rate, median progression-free survival (PFS), and 3-year PFS rate were 37 months, 64.4%, 31 months, and 40%, respectively. PFS and OS were significantly inferior in patients who presented with features of obstruction than in those who did not (P=0.0001). There was no difference in survival with respect to tumor histology (well to moderately differentiated vs. poorly differentiated, signet ring vs. non-signet ring histology) or location (proximal vs. distal). Survival was prolonged in patients with an early pathological T stage and a pathological node-negative status. In a multivariate analysis, postoperative pathological nodal status and gastric outlet obstruction on presentation significantly correlated with survival. Conclusions: EOX chemotherapy with curative resection and D2 lymphadenectomy is a suggested alternative to the existing perioperative regimens. The acceptable postoperative complication rate and relatively high resections, chemotherapy completion, and survival rates obtained in this study require further evaluation and validation in a clinical trial.

• Tuberculosis and Respiratory Diseases
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• 제80권1호
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• pp.52-59
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• 2017

Background: Inhaled indacaterol (Onbrez Breezhaler), a long-acting ${\beta}_2$-agonist, is approved in over 100 countries, including South Korea, as a once-daily bronchodilator for maintenance and treatment of chronic obstructive pulmonary disease (COPD). Here, we present an interim analysis of a post-marketing surveillance study conducted to evaluate the real-world safety and effectiveness of indacaterol in the Korean population. Methods: This was an open-label, observational, prospective study in which COPD patients, who were newly prescribed with indacaterol (150 or $300{\mu}g$), were evaluated for 12 or 24 weeks. Safety was assessed based on the incidence rates of adverse events (AEs) and serious adverse events (SAEs). Effectiveness was evaluated based on physician's assessment by considering changes in symptoms and lung function, if the values of forced expiratory volume in 1 second were available. Results: Safety data were analyzed in 1,016 patients of the 1,043 enrolled COPD patients receiving indacaterol, and 784 patients were included for the effectiveness analysis. AEs were reported in 228 (22.44%) patients, while 98 (9.65%) patients reported SAEs. The COPD condition improved in 348 patients (44.4%), while the condition was maintained in 396 patients (50.5%), and only 40 patients (5.1%) exhibited worsening of ailment as compared with baseline. During the treatment period, 90 patients were hospitalized while nine patients died. All deaths were assessed to be not related to the study drug by the investigator. Conclusion: In real-life clinical practice in South Korea, indacaterol was well tolerated in COPD patients, and can be regarded as an effective option for their maintenance treatment.

• 한국도로학회논문집
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• 제4권1호
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• pp.123-134
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• 2002

본 연구에서는 국도 아스팔트 포장의 포장파손예측모델을 개발하기 위한 장기 공용성 관측 구간을 선정하였다. 관측 구간의 선정을 위하여 신설 포장 구간 및 덧씌우기 포장 구간에 대한 실험계획표를 작성하였고, 실험계획표의 각 셀에 해당되는 구간은 국도 데이터 베이스를 이용하여 예비 관측 구간을 선정하였고, 현장 조사를 통하여 최종 관측 구간을 선정하였다. 선정된 관측 구간의 단위 연장은 200m이며, 신설 포장 구간 47개소 및 덧씌우기 포장 구간 48개소가 선정되었다. 선정된 관측 구간에 대하여 시간의 변화 또는 교통량의 변화에 따른 포장 상태를 바탕으로 균열 및 러팅에 관한 1차 분석 작업을 진행하였다. 향후 포장 관련 다양한 정보가 데이터 베이스에 구축된 후 통계분석을 통하여 포장 파손 예측 모형이 개발되어야 할 것이다.

• 한국도로학회논문집
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• 제19권2호
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• pp.113-126
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• 2017

PURPOSES : This study proposes standards for rural access road pavement section and thickness design considering existing access road construction conditions; the study also proposes a complementary policy that can be used for design convenience. METHODS : Various literature review and case studies had been performed in terms of rural access road section and thickness design, both domestically and internationally, and this was followed by domestic rural access road field surveys. KPRP and KENLAYER were used to analyze the commonalities and predict the remaining life. Data on real cost is used to select an appropriate construction method through economic analysis. RESULTS : The economic efficiency of concrete pavement ($15{\times}15$) was the highest in terms of economic efficiency of performance life and traffic volume. In the case of asphalt pavement, it is considered that the most economical method is to implement micro-surfacing method four times as a preventive maintenance method (once every 10 years and 4.5 years for asphalt concrete pavement and MS construction method, respectively). Repairable asphalt pavement is advantageous for areas where heavy vehicles are expected to pass. In the case of other general areas, it is considered economical to place concrete ($15{\times}15$) pavement. However, as analytical results on its performance life are unavailable, it is to be considered for study in the future. CONCLUSIONS : This study proposed interim design guidelines based on various domestic and international design guidelines and case studies. However, in order to develop the final design criteria applicable to the field, it is necessary to (a) estimate the bearing capacity of the lower level of the pavement at various sites, (b) estimate the daily traffic volume, (c) implement advanced low-cost pavement technologies, and (d) propose maintenance standards and techniques for long-term performance.

• 대기
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• 제26권2호
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• pp.301-319
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• 2016

The evolutionary process of the polar low, which caused the heavy snowfall in the East Coast area on 11~12 February 2011, was investigated to describe in detail using synoptic weather charts, satellite imageries, and ERA (European Centre for Medium-Range Weather Forecasts Re-Analysis) -Interim reanalysis data. It was revealed that 1) the polar low was generated over the sea near Busan where a large cyclonic shear in the inverted trough branched from the parent low existed, 2) during the developing and mature stages, there was a convectively unstable region in the lower layer around the polar low and its south side, 3) the polar low was developed in the region where the static stability in the 500~850 hPa layer was the lowest, 4) the result from the budget analysis of the vorticity equation indicated that the increase in the vorticity at the lower atmosphere, where the polar low was located, was dominated mainly by the stretching term, 5) the warm core structure of the polar low was identified in the surface-700 hPa layer during the mature stage, 6) there was a close inverse relationship between a development of the polar low and the height of the dynamic tropopause over the polar low, and 7) for generation and development of the polar low, large-scale circulation systems, such as upper cold low and its combined short wave trough, major low (parent low), and polar air outbreak, should be presented, indicating that the polar low has the nature of the baroclinic disturbance.

• 한국기후변화학회지
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• 제9권3호
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• pp.209-221
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• 2018

The characteristics of heat wave events in Seoul are analyzed using weather station data from Korea Meteorological Administration (KMA) and European Centre for Medium-Range Weather Forecast (ECMWF) ERA-Interim reanalysis data from 1979 to 2016. Heat waves are defined as events in the upper 10th percentile of the daily maximum temperatures. The associated synoptic weather patterns are then classified into six clusters through Self-Organizing Map (SOM) analysis for sea-level pressure anomalies in East Asia. Cluster 1 shows an anti-cyclonic circulation and weak troughs in southeast and west of Korea, respectively. This synoptic pattern leads to southeasterly winds that advect warm and moist air to the Korean Peninsula. Both clusters 2 and 3 are associated with southerly winds formed by an anti-cyclonic circulation over the east of Korea and cyclonic circulation over the west of Korea. Cluster 4 shows a stagnant weather pattern with weak winds and strong insolation. Clusters 5 and 6 are associated with F?hn wind resulting from an anti-cyclonic circulation in the north of the Korean Peninsula. In terms of long-term variations, event frequencies of clusters 4 and 5 show increasing and decreasing trends, respectively. However, other clusters do not show any long-term trends, indicating that the mechanisms that drive heat wave events in Seoul have remained constant over the last four decades.

• 교육녹색환경연구
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• 제20권2호
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• pp.22-30
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• 2021

2020년 개최된 OECD의 한국교육 분석 중간보고에 따르면 발표자 안드레아스 슐라이허 OECD 교육국장은 '한국 학생들은 실패에 대한 두려움과 불안감, 초조함을 많이 보인다'며 시험 점수가 괜찮아도 긴장감을 느끼는 모습에 대하여 말했다. 단적인 예시이지만 최근의 교육 발표에 언급된 만큼 한국의 학생들에게서 흔히 찾아볼 수 있는 모습이며 교육을 받으며 쉽게 겪는 일이다. 한국이 인적자원 양성 있어서 관심과 열의가 높은 만큼 그 방법에도 여러 가지 것이 고려되고 연구되고 현재의 문제에 대한 해결책과 개선점, 발전 방향이 제시되어야 하는 상황이다. 본 논문은 학교 교육의 질 개선에 있어서 배움 공간 혁신의 방안에 대해 생각해보았으며, 그 방법과 수단 중에서도 녹색환경제공의 효과와 영향에 대하여 체계적으로 분석·정리하였다. 기존에 제시된 학생들의 복합적 양상의 사회적 문제 해결에 본 학술이 작은 한 가지의 해결책과 역할이 될 수 있길 바란다.