• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.410-410
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• 2019

기후변화는 전 지구적인 환경문제 중 하나이며 IPCC (Intergovernmental Panel on Climate Change) 4차 평가보고서에서는 인류가 직면한 최대 위협이라고 하였다. 또한, IPCC는 현재 기후변화에 의한 영향은 명백히 나타나고 있으며 향후 기후변화에 의한 기상이변 예측과 적응 정책 및 조치가 중요하다고 권고하였다. 적응 정책 및 조치를 위한 기후변화의 영향분석은 우리나라에서도 많이 진행하고 있으나 개별 및 분류의 선형의 순차적 관계에 따라 개발 및 적용되고 있다. 기후변화는 자연생태계와 인간 활동의 복잡한 상호작용에 의해 발생하기에 개별적 연구 보다는 타 부문의 영향 및 결과가 환류되고 반영되어야 한다. 따라서 기후변화 영향평가는 농업, 물, 산림, 생태, 건강 등 다양한 부문 내/간 상호작용을 고려할 수 있는 통합 평가 방법이 필요하다. 통합 평가를 위해 플랫폼 개발은 필수적이며, 신속한 분석을 위해서는 개별 부문의 상세모델을 모방한 메타모델이 필요하다. 본 연구에서는 미래 기후변화에 따른 영향을 통합적으로 평가하기 위한 메타모델을 개발하고, 상호 연결을 통해 다양한 연계양상을 평가하고자 한다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.4
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• pp.42-48
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• 2004

This paper concerns on a multiprocessor task scheduling problem with precedence relation, in which each task requires several processors simultaneously. Meta-heuristic generally finds a good solution if it starts from a good solution. In this paper, a tabu search is presented to find a schedule of minimal time to complete all tasks. A modified tabu search is also presented which uses a new initial solution based on the best solution during the previous run as the new starting solution for the next iteration. Numerical results show that a tabu search and a modified tabu search yield a better performance than the previous studies.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.4
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• pp.75-82
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• 2006

The main objective of this study is to find out the shortest path of the vehicle routing problem with time window constraints by using both genetic algorithm and heuristic. Hard time constraints were considered to the vehicle routing problem in this suggested algorithm. Four different heuristic rules, modification process for initial and infeasible solution, 2-opt process, and lag exchange process, were applied to the genetic algorithm in order to both minimize the total distance and improve the loading rate at the same time. This genetic algorithm is compared with the results of existing problems suggested by Solomon. We found better solutions concerning vehicle loading rate and number of vehicles in R-type Solomon's examples R103 and R106.

• Journal of Chest Surgery
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• v.54 no.4
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• pp.294-301
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• 2021

Recent case series and meta-analyses have suggested that robot-assisted minimally invasive esophagectomy (RAMIE) could be a useful alternative to video-assisted thoracic surgery esophagectomy. The advantages of RAMIE are a 3-dimensional view, 7 degrees of freedom, and tremor filtering, which enable more meticulous lymph node dissection with a lower incidence of complications. However, in radical esophagectomy, understanding the concepts of the fascia and compartment is crucial for successful and reliable dissection. The first RAMIE in Korea was performed by our team in July 2006, and since then, we have developed related techniques to achieve better short- and long-term outcomes. The key step in RAMIE for esophageal squamous cell carcinoma is dissection of the upper mediastinum due to the difficulty of lymph node dissection and the high incidence of nodal metastasis in the area. Herein, we describe the technique of fascial plane dissection with esophageal suspension during RAMIE.

• International Journal of Advanced Culture Technology
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• v.7 no.1
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• pp.96-102
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• 2019

The purpose of this study was to examine the effects of applying a program to enhance social information processing ability in schizophrenic patients. We confirmed the positive effects of the program on the theories of mind and attribution style, which are the social information elements of patients, and confirmed the effect of decreasing paranoid ideation. We used the theory of mind(hinting task, the false belief task), the attributional style questionnaire(external bias, personal bias), and the paranoia scale to test the effectiveness of the program. Specifically, in theory of mind, hinting task performance was improved(t=4.14, p=.000),. The scores of personal bias(t=-7.9, p=.000) and paranoid ideation(t=-2.98, p=.004) decreased. Further research is needed to verify the effectiveness of meta - cognitive training to enhance social information processing.

• Advances in Energy Research
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• v.8 no.3
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• pp.175-184
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• 2022

The dual-fuel technology, which uses gaseous fuel as the main fuel and liquid as the pilot fuel, is an appealing technology for reducing the exhaust emissions. The current study proposes emission models based on ANFIS for a dual-fuel using producer gas (PG)-diesel engine. Emissions measurements were taken at different engine load levels and fuel injection timings. The proposed model predictions were examined using statistical methods. With R2 values in the range of 0.9903 to 0.9951, the established ANFIS model was found to be consistently robust in predicting emission characteristics. The mean absolute percentage deviate in range 1.9 to 4.6%, and mean squared error varies in range 0.0018 to 13.9%. The evaluation of the ANFIS model developed shows a reliable claim of intrinsic sensitivity, strength, and outstanding generalization. The presented meta-model can be used to simulate the engine's operation in order to create an efficient control tool.

• International Journal of Knowledge Content Development & Technology
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• v.13 no.1
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• pp.75-100
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• 2023

With research data generation on the rise, Institutional Repositories (IR) are one of the tools to manage it. However, the variety of data practices across institutions, domains, communities, etc., often requires dedicated studies in order to identify the research data management (RDM) require- ments and mapping them to IR features to support them. In this study, we investigated the data practices for a few national universities in North Macedonia, including 110 participants from different departments. The methodology we adopted to this end enabled us to derive some of the key RDM requirements for a variety of data-related activities. Finally, we mapped these requirements to 6 features that our participants asked for in an IR solution: (1) create (meta)data and documentation, (2) distribute, share, and promote data, (3) provide access control, (4) store, (5) backup, and (6) archive. This list of IR features could prove useful for any university that has not yet established an IR solution.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.07a
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• pp.135-136
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• 2022

메타버스란 가공, 추상을 의미하는 메타(Meta)와 현실을 의미하는 유니버스(Unvierse)의 합성어이며 가상의 3차원을 뜻한다. 현재 메타버스는 4차 산업혁명의 중요 트렌드로 지목되어지고 있으며 다양한 기업들의 투자 또한 지속적으로 증가하는 추세이다. 이중 게임은 메타버스에서 가장 많은 비중을 차지하고 있으나 아직까지 메타버스 게임의 신뢰도가 높지 않으며 현재 출시되었거나 앞으로 출시될 게임들에 대한 적합한 테스트 기법이 필요한 실정이다. 이에 본 논문에서는 메타버스를 기반으로 하는 게임 테스팅에 강화학습 에이전트를 활용하는 방안에 대해 제안한다.

• Journal of The Korean Association For Science Education
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• v.37 no.1
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• pp.87-101
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• 2017

The analysis was carried out with meta-analysis on master's and doctoral dissertations, and academic journals that analyzed the effects of STEAM education between 2012 and 2015. From the total number of 75 dissertations and articles analyzed, 183 different effect sizes were calculated. The analysis was done to find out the kinds of differences that would be created according to the effect size of creativity, problem-solving ability, and researcher, target area, student division research design type, and level of schools. The total effect size of creativity scored 0.776, and demonstrated satisfaction in symmetry of funnel plot, with no publication biases. The fail-safe N scored 780, and since the number is smaller than 8,945, the results of this research has credibility. Furthermore, problem-solving ability shows intermediate level of effect size with a score of 0.584. It also showed satisfaction in symmetry with funnel plot, with no publication bias. With the different research methods of the sub-factors of creativity, fluency scored the highest with 0.929, flexibility with 0.881, originality with 0.838, sophistication with 0.653, abstractness with title 0.705, and resistance to termination, 0.527. This study finds its significance in the demonstration of average effect size of STEAM education through meta-analysis. According to research results, the effects of inclusive education could be determined, yet the specific effect cause or learning principles were difficult to find. It was found that the effects of STEAM education do not rise or fall depending on school age, and demonstrated differences in creativity according to the research methods or the researchers.

• Journal of Korean Society on Water Environment
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• v.26 no.4
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• pp.664-672
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• 2010

This study was performed to evaluate the feasibility of industrial by-products such as converter slag, olivine, red mud and fly ash as a seed crystal of struvite crystallization for the removal of highly concentrated $NH_4-N$ and $PO_4-P$. In the kinetic experiments, more than 90% of $NH_4-N$ and $PO_4-P$ was eliminated by struvite crystallization within 30 minutes of reaction time. The pH range in meta-stable region of struvite crystallization was found to be pH 7.0~9.0 under the Mg:N:P=1:1:1 equi-molar condition with 100 mg/L of $NH_4-N$. Total removal efficiencies of $NH_4-N$ and $PO_4-P$ by both struvite precipitation and crystallization were increased with the increase of pH. Removal efficiencies of $NH_4-N$ and $PO_4-P$ were significantly enhanced by struvite crystallization using industrial by-products as a seed crystal compared with those by struvite precipitation without seed crystal. Red mud, converter slag, olivine and fly ash enhanced the removal efficiencies of $NH_4-N$ by 40.9%, 37.7%, 28.4% and 16.4%, respectively. Removal efficiencies of $PO_4-P$ for converter slag, red mud, fly ash, olivine were increased by 3.7 times, 2.6 times, 72.4% and 68.0%, respectively. Converter slag and red mud showed higher feasibility as a seed crystal than others for the removal of highly concentrated $NH_4-N$ and $PO_4-P$. In particular, converter slag might have a high capacity of phosphorus removal.