• 대한교통학회지
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• 제26권3호
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• pp.145-153
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• 2008

본 연구에서는 천연가스버스 충전소 위치 선정의 객관성과 효율성을 확보하기 위한 노력의 일환으로 공간적 접근성과 통행 비용을 고려한 천연가스 충전소 입지선정 모형을 개발하였다. 본 연구에서 제시한 충전소 입지선정 모형은 고정식 충전소를 대상으로 하였으며, 2단계로 구성되었다. 1단계에서는 천연가스버스의 노선 기종점으로부터 이동거리 제약조건을 만족하는 충전소 입지 대안들을 Heuristic Algorithm을 통해 선정하였으며, 모형의 2단계에서는 변형된 Transportation Problem을 이용하여 충전소 입지대안별 최소 통행비용을 산출하고 이를 충전소의 설치 및 운영비용과 비교분석하여 충전소 최적 입지대안을 도출하였다. 본 모형의 적용가능성 분석을 위해 수도권내의 대표적 중소도시인 안양시를 대상으로하여 천연가스버스 수요량에 따른 충전소의 입지와 규모를 산출하였다. 본 연구를 통해 객관적이고 합리적인 천연가스 충전소 입지선정 방법론의 기틀을 제시함으로써 향후 천연가스버스의 원활한 보급에 기여할 수 있을 것으로 판단된다.

• Computers and Concrete
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• 제19권5호
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• pp.489-499
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• 2017

Self-Compacting Concrete (SCC) is a new technology capable to flow without segregation or any addition of energy which leads to efficient construction and cost savings. In this study, the effect of replacing the Ordinary Portland Cement (OPC) with Fly Ash (FA) on the strength, durability of the concrete was investigated experimentally, and carbon footprint and cost were also assessed. Four different replacement FA ratios (0%, 20%, 40% and 60%) were used to create four SCC mixes. Standard test methods were used to determine the workability, strength, and durability of the SCC mixes including resist chloride ion penetration, water permeability, water absorption, and initial surface absorption. The axial cube compressive strength tests were performed on the SCC mixes at 1, 7, 14, 28 and 35 days. Replacing the OPC with FA had a significant positive impact on chloride iron penetration resistance and water absorption but had a considerable negative impact on the compressive strength. The SCC mix with 60% FA had 36.7% and 15.8% enhancement in the resistance to chloride ion penetration and water absorption, respectively. Evaluation of the carbon footprint and the cost of each SCC mixes showed the $CO_2$ emissions mixes 1, 2, 3 and 4 were significantly reduced by increasing the FA content from 0% to 60%. Compared with the control mix, the cost of all mixes increased when the FA content increased, but no significant differences were seen between the estimated costs of all four mixes.

• 상하수도학회지
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• 제37권6호
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• pp.409-423
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• 2023

In this study, we analyzed how the revenue water ratio(RWR) is affected by changes in conditions of the water supply area, such as the ratio of aging pipes, maintenance conditions, and revenue water. As a result of analyzing the impact of pipe aging and maintenance conditions on the RWR, it was confirmed that the RWR could be decreased if the pipe replacement project to improve the aging pipe ratio was not carried out and proper maintenance costs were not secured. It was also confirmed that an increase in the revenue water could be operated to facilitate the achievement of the project's target RWR. In contrast, a decrease in the revenue water due to a population reduction could affect the failure of the target RWR. In addition to analyzing the causes of variation in the RWR, the calculation of estimated project costs was considered by using leakage reduction instead of RWR from recent RWR improvement project cost data. From this analysis, it was reviewed whether the project costs planned to achieve the target RWR of the RWR improvement project in A city were appropriate. In conclusion, the RWR could be affected by variations in the ratio of aging pipes, maintenance conditions, and revenue water, and it was reasonable to consider not only the construction input but also the input related to RWR improvement, such as leakage reduction, when calculating the project cost.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.696-700
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• 2007

In case of dome-typed gymnastics training floor, since its form takes shape of the focus of sound, in the occasion when the finishing-material was used with the sandwich panel that prominent in reflexibility, and because the reverberation of sound in indoor is too loud, a smooth practice and teaching is very difficult. As this indoor gymnastics training floor, standing at its character, is required simultaneously the idea communication between the player and the coach, and the acoustic capability regarding to the clearness of music, besides the sport activity, the method to minimize the acoustic defect should be urgently contrived from the stages of design and beginning of construction. On this viewpoint, after investigation on the confidence of the surveyed value and the estimated value using acoustic simulation, and use of the changed finish-material, this thesis intends to design the dome-typed gymnastics training floor that secured the optimized acoustic condition. It is also considered that such result of the study could be utilized as the useful data that enables to improve the retrenchment effect of the construction cost as well as the acoustic performance, by means of the prediction control on the acoustic problem from the stage of design, for the occasion when the similar indoor sport gymnasium is planning to build for the near future.

• Environmental Engineering Research
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• 제20권4호
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• pp.356-362
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• 2015

Many burial sites were constructed in a short time to prevent the rapid spread of foot and mouth disease in infected livestock carcasses in Korea. More than 4,700 carcass burial sites were constructed in 2011. Approximately seven million poultry and 3.5 million livestock, including cattle and swine, were buried on farmland. Some burial sites were suspected of leachate leakage and were excavated and carcasses redisposed in a bioaugmentation process. This study performed interviews in order to understand the economic issues related to carcass burial and redisposal. The internal data from local government and the assumption data from online sites were analyzed to evaluate the costs; the focus was on burial site construction. The results showed that the local government paid $4.7 and $10.9 per carcass for traditional burial and redisposal. The comparable costs shown online were $4.5. This study found that the standard operating procedures should be carried out to reduce environmental impact and avoid additional costs. We estimated that the cost could be reduced by the advance preparations of materials against the emergency situations such as catastrophe of epidemics. In addition, the innovative technology for the stabilization of carcasses should be established through a future study.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.948-955
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• 2005

In this case of study, Incheon International Airport 2nd phase site preparation 1st section estimated final settlement to improve soft ground. Final settlement is very important in preloading method. Recently, Hyperbolic method, Hoshino method and Asaoka method are used mostly in prediction of final settlement and this paper, Comparing a result of Final settlement, used to Artificial Neural Network. The structure of Dynamic Artificial Neural Network which predicted Final settlement, has application to Young_Jong Island other site, If new investigation data will be added. Also, It is expected to save measuring_system cost in soft ground.

• 한국도로학회논문집
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• 제16권6호
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• pp.181-189
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• 2014

PURPOSES : Ambiguous decision on whether rural or urban area for road design can increase the construction cost and restrict the land use of surrounding area. However, administrative classification on rural and urban area is not directly related to road design because of this classification is not based on the engineering viewpoint, so method which can explain the road design context is required. METHODS : Method which enables to identify the area for road design is suggested based on the deceleration expected to be experienced by drivers who use the road section concerned. Deceleration rate corresponding to the area such as rural or urban suggested in Road Design Guideline is used as the criteria to identify the area by comparing this value with the estimated deceleration rate at the road section concerned. Speed profile method is utilized to derive the deceleration rate, and speed estimation way for reflecting both road geometry and intersection is suggested using stopping sight distance concept. RESULTS : The procedure of the method application is suggested, and the design example utilizing the method is provided. CONCLUSIONS : The method is expected to be used to identify the area for road design with engineering viewpoint, and design consistency among the roads with similar driving environment can be made.

• 화약ㆍ발파
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• 제25권2호
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• pp.35-46
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• 2007

발파는 지반굴착 시 경제적으로 우수하고 과정이 간편하기 때문에 다양한 지반시설, 건축물에 널리리 적용된다. 발파에 의한 지반진동은 많은 실험과 연구로 제시되었지만 폭풍압에 의한 환경적 영향은 간과 하는 경향이 있다. 환경문제 대립의 경우에 지나치게 민감하고 논쟁의 여지가 있는 구조물에 대한 소음은 발파분야에서 무시되는 경향이 있다. 이에 비추어 이 연구는 폭풍압의 예상 진행방향을 조사하였다. 실제 폭풍압과 소음을 추정한 다음 회귀분석을 사용한 지발당 장약량에 기초를 두고 확실한 추정식을 만들었다. 추정식과 실제 결과치의 비교는 추정식의 타당성을 결정하는데 도움이 될 것이다.

• 한국항만경제학회지
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• 제17권1호
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• pp.129-157
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• 2001

In Korea, the quantity of waste is excessive as a result of increases in population and consumption following industrialization. This has resulted in urban environmental problems, a shortage of landfills and pollution around landfills. Thus, there is a need to conduct research in order to find an effective long-term alternative. In Japan, there are more landfills at sea than there are on land. Based on projections for Korea, on-land landfills in the metropolitan area will be filled to capacity by 2020 and then be closed. This research recommends the construction of landfill sites at sea as an alternative waste disposal method. Its findings show that the most the suitable sites for landfills within the Seoul metropolitan area are the regions around Jangbongdo Island and Mueido Island. It also suggests that the best way to transport waste is through the Kyungin Canal from the middle collection center to the lower Han River. The estimated cost of constructing an at-sea landfill to be used for 50 years is approximately two trillion won, with a total construction time of 10 years. In the future, further research related to this study will be conducted in order to ensure that environmentally-friendly landfills are built.

• 대한토목학회논문집
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• 제36권5호
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• pp.881-889
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• 2016

VE 평가에서 가치는 비용, 성능의 요소로서 구성이 되며, 이러한 요소들의 적절한 가치를 달성하기 위하여 정성적인 접근보다는 구체적인 수치로써 정량적으로 분석하는 특징을 가지고 있다. 현재 많은 국내 VE 평가에서 비용부분은 정량화하여 산정하고 있지만 기능부분은 정량화를 위한 체계적인 절차가 존재하지 않는다. 또한, VE 평가는 실무 성향이 강한 특성과 함께 과도한 정량화 및 객관화가 창의적인 의견 도출을 저하시킬 수 있다는 문제점들로 인해 과학적인 분석 방법론의 실제 적용에 한계가 존재하고 있다. 이에 본 연구에서는 실무적인 관점에서 VE 평가의 본질을 저해하지 않으며, VE 프로세스의 단순화와 객관화를 동시에 만족시킬 수 있는 VE 프로세스 단계별 개선 평가 방법론을 제시한다.