• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권4호
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• pp.1276-1295
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• 2023

Sensor networks are now an essential aspect of wireless communication, especially with the introduction of new gadgets and protocols. Their ability to be deployed anywhere, especially where human presence is undesirable, makes them perfect choices for remote observation and control. Despite their vast range of applications from home to hostile territory monitoring, limited battery power remains a limiting factor in their efficacy. To analyze and transmit data, it requires intelligent use of available battery power. Several studies have established effective routing algorithms based on clustering. However, choosing optimal cluster heads and similarity measures for clustering significantly increases computing time and cost. This work proposes and implements a simple two-phase technique of route creation and maintenance to ensure route reliability by employing nature-inspired ant colony optimization followed by the fuzzy decision engine (FDE). Benchmark methods such as PSO, ACO and GWO are compared with the proposed HRCM's performance. The objective has been focused towards establishing the superiority of proposed work amongst existing optimization methods in a standalone configuration. An average of 15% improvement in energy consumption followed by 12% improvement in latency reduction is observed in proposed hybrid model over standalone optimization methods.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2003년도 학술대회지
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• pp.290-293
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• 2003

건설산업의 조직운영은 생산성 및 원가절감에 중요한 요소이다. 그러나 현재 조직개선을 위한 노력이 부족할 뿐만 아니라 조직의 평가방법 또한 체계적으로 갖추고 있지 않다. 본 연구는 공동주택 및 오피스의 현장조직원 선정실태 분석을 통하여 현장조직인의 선임방법, 직급, 및 인원수 결정기준, 자격조건등을 종합하여 제시하였고, 현장 조직원의 선정절차를 제안하였다. 또한 현장관리조직원에 활동에 대한 평가실태 분석을 통하여 현장소장에 대한 평가항목 및 배점, 준공현장에 대한 평가항목 및 배점을 제안하였다. 따라서 본 연구의 결과는 건설공사의 현장관리조직원의 선정 및 평가에 대한 기준을 체계적으로 갖추지 못한 건설기입에 효율적인 조직운영을 위한 기초자료 제공함으로써 생산성향상 및 원가절감에 기여하고자 한다.

• Nuclear Engineering and Technology
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• 제54권5호
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• pp.1712-1725
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• 2022

For improving the seismic performance of the nuclear power plant (NPP) piping system, attempts have been made to apply a dynamic absorber (DA). However, the current piping DA design method is limited because it cannot provide the globally optimum values for the target design seismic loading. Therefore, this study proposes a seismic time history analysis-based DA optimal design method for piping. To this end, the Kriging approach is introduced to reduce the numerical cost required for seismic time history analyses. The appropriate design of the experiment method is used to increase the efficiency in securing response data. A gradient-based method is used to efficiently deal with the multi-dimensional unconstrained optimization problem of the DA optimal design. As a result, the proposed method showed an excellent response reduction effect in several responses compared to other optimal design methods. The proposed method showed that the average response reduction rate was about 9% less at the maximum acceleration, about 5% less at the maximum value of the response spectrum, about 9% less at the maximum relative displacement, and about 4% less at the maximum combined stress compared to existing optimal design methods. Therefore, the proposed method enables an effective optimal DA design method for mitigating seismic response in NPP piping in the future.

• 한국환경복원기술학회지
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• 제13권1호
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• pp.93-102
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• 2010

Greening sometimes fails because its method is not suitable for various site conditions, therefore the trend of selecting a revegetation method in Korea today is through test construction. However, due to enlargement, complication and diversification of domestic construction businesses, the importance of VE is gradually increasing as effective efforts over a whole life-cycle to obtain goals such as quality improvement and cost reduction, and not only quality and economic efficiency but also substantiality need to be considered in comparing revegetation methods. For this study, Sungnam~Janghowon (area1), where comparatively various slope revegetation methods are used, was selected the investigation site. The site was divided into three areas:blasting rock, ripping rock and earth sand. The revegetation methods used were six in the blasting rock area, five in the ripping rock area, and two in the earth sand region. 2007 monitoring data was analyzed, and Value (V) was calculated with LCC related ratio, and compared and contrasted with the evaluation of prior revegetation methods. Therefore it is believed that this analysis enables selection of the most appropriate method, unbiased towards one particular characteristic such as quality, vegetation growth and economy. When aiming for a durable effect, it shall be more efficient to select the most appropriate method focusing on LCC analysis, which deals with the economic aspect, as well as the design function aspect.

• 디지털정책학회지
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• 제2권4호
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• pp.17-23
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• 2023

본 논문에서는 중소 규모의 정밀 가공 기업에 대한 생산 가공의 개선을 위하여 기존 공정 방식에 제조 실행 시스템을 적용하고 정밀가공의 데이터를 통합하였다. 이에 따른 기업 내 공정 관리 시스템의 강화, 장비 운용 효율의 증대, 불량률 감소를 통한 생산성 향상 및 작업 공수 감소에 따른 원가 절감률의 차이를 비교 분석하였다. 그 결과 제조 실행 시스템 도입으로 인해 생산 업무 생산성이 7.0% 향상되었고, 제품 불량률은 0.1%p 개선되었다. 제조원가 절감은 10.0%, 납기 준수율은 1.1% 개선되었음을 확인하였다. 추후 본 연구에서 제안한 제조 실행 시스템을 기반으로 추가적인 스마트팩토리 기술을 적용하는 경우 PQCD 지표의 상승으로 인한 가공 산업의 매출 및 이익 증대가 예상된다.

• 대한약침학회지
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• 제24권4호
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• pp.153-164
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• 2021

Objectives: Despite the low cost and high accessibility of manual acupuncture (MA) treatments for the carpal tunnel syndrome (CTS), this intervention has not been uniformly evaluated in systematic reviews (SR), and no SR has evaluated MA monotherapy for CTS. This review was conducted to summarize the findings and undertake a quality assessment of randomized controlled trials (RCTs) of acupuncture treatment methods for mild-to-moderate CTS to identify clinical evidence for the use of MA in CTS. Methods: We searched five databases for articles on relevant RCTs that were published until June 2021 without imposing specific restrictions, such as age or sex, on CTS patients. RCTs that evaluated MA were included without any restriction on comparator interventions. Measurement tools for evaluating pain reduction and functional improvement or for evaluating efficacy using electrophysiological indicators were included as outcome measures. Results: We included seven RCTs, of which three studies reported both post-treatment improvement effects and statistical significance using p-values for all outcomes. Five studies reported statistically significant intergroup differences (p-values for all outcomes) in posttreatment improvement. None of the studies reported severe adverse effects of MA. In all of the RCTs, the reporting rates of the 2c, 2a, and 6a items of STRICTA 2010 were 14%, 29%, and 29%, respectively. PC7 (Daereung) was used to treat CTS in all of the included studies. Conclusion: MA can be used for CTS treatment without serious adverse effects. PC7 was the most commonly used acupoint. In order to ensure objective and reliable reporting, accurate standardization of acupuncture treatment methods acupoint terms should be undertaken in future RCTs.

• 한국건축시공학회지
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• 제7권1호
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• pp.99-106
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• 2007

Water leakage could be caused deterioration of environmental conditions, user condition, reduction of life span and long term safety in underground concrete structure. Many materials and construction method to repair on these problems have been developed, however, it is not proper to successful repair or raise problem of increasing repair cost However, there are many limitations as practical appraisal methods due to different view of reliability for test methods. Because, it was not enough that the technical objectivity could be lack and also application of environmental condition is inadequate. In this paper, we suggest varied test methods divided to appraisal for property of matter, construction, manufacturing, specification and maintenance, friendly environmental condition. It could be more practical as a objective standard considering various angles. In summery, it should be subdivided and differentiated to accomplish proper application and to select proper materials and construction method for repair even if the synthetical condition is very complicated.

• 한국안전학회지
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• 제14권2호
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• pp.163-169
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• 1999

Safety education should not only prevent workers from industrial accidents but also contribute to improve the productivity of manufacturing plants or construction sites. In practice this do not happen because workers do not realize the importance of safety education. This study aims to suggest a methodology to improve safety education of construction sites by surveying conditions of safety education and the safety consciousness of workers and engineers. The results showed that most education except regular educations were nominally carried out. Lectures and audio-visual education were mainly used as educational methods. After trainees attended the education session they completed a written survey, the most dissatisfied factor about safety education was education circumstances, of which rate was around 36%. The proportion of construction engineers who thought that safety management was contributable to cost reduction was 35%, to construction period 20%, and to quality enhancement 48%. Based on these results, this research pointed out the need to review training manuals, the development of educational programs, improvement of educational facilities to improve safety education of construction sites, and finally to discussed these issues.

• 대한안전경영과학회지
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• 제5권2호
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• pp.11-26
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• 2003

While a number of Korean companies have undergone ceaseless restructuring to survive today's rapidly changing global economy, the brick and mortar industry has been exerting their efforts to enhance the productivity through the development of new products, quality improvement, cost reduction measures. At present, various risk-evaluation measures have been taken in the fields at the discretion of an enterpriser, though, the effective methods enabling quantitative analysis are insufficient. Accordingly, this study is intended to contribute to the synthetic safety manage -ment in the factory fields and to suggest the quantitative -risk-analysis system by introducing such safety-estimation steps as assortment of processes, pre-assessment of risk factors, decision of risks, counter measures against studied risks, establishment of remedies.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1642-1649
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• 2010

At present, KORAIL is in the middle of renovating. All steps exert great effort at cost reduction and a profit improvement. Especially to improve maintenance method and inspection period at the rolling-stock division lots of research is under progress. Daily inspection of rolling stocks is to operate the rolling stock normally. Daily inspection items are driving control device, coupling device, brake system, water system and air conditioning system, electrical system etc. Half of the maintenance manpower are inputted at daily inspection. Strengthens the quality and optimize the proportion of daily inspection are urgent problem. Daily inspection period extension aim is as follows. KTX from 3,500km to 5,000km, passenger car from 1st to 3,500km, new style electric locomotive from 2nd to 5,000km, the diesel locomotive is 2,800km from 1,200km. In this paper, the optimal daily inspection period and methods are considered including expected problem and counter measures.