• 청정기술
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• 제19권2호
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• pp.173-183
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• 2013

전 세계적으로 자원순환 효율성 증대 및 에너지 절감을 위해 친환경제품 설계, 재활용, 재제조 등 다양한 방법론이 제시되고 있다. 본 논문은 하나의 방안으로 유니소재화에 대해서 제시하고 있다. 유니소재화는 제품 재활용이 용이하고 유해물질 사용을 저감하기 위해 설계, 생산, 수거, 재활용 등을 고려한 기존 제품의 소재의 단일화(단순화)로 정의한다. 본 연구에서는 적용 가능한 유니소재화 대상제품을 평가할 수 있는 정성적, 정량적 평가 항목을 개발하였다. 평가항목은 경제성, 기술성, 환경성을 고려하여 총 9가지로 구성되어 있으며 평가항목을 적용하여 4가지 대상제품에 대해 사례를 연구했다. 연구 결과, 블라인드형 창문을 제외한 3가지 대상제품은 유니소재화 제품으로 적용이 가능하며 평가항목의 객관성을 높이기 위해서는 유니소재화의 개념을 구체화하고 산업별 특성을 고려하여 평가할 필요가 있다.

• 대한산업공학회지
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• 제41권4호
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• pp.352-358
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• 2015

It is important to guarantee the safety of vehicle to minimize the damage to the driver in case of the accidents. In order to inspect and later enhance the safety of vehicle, the owner of the vehicle usually have a vehicle safety inspection. The Korea Transportation Safety Authority (KOTSA) issues the Comprehensive Performance Inspection Certificate after vehicle inspection. The certificate only specify the legal inspection criteria for safety and measured values of the safety parameters, however, as ordinary driver in lack of expert knowledge about the vehicle is difficult to understand the contents of the Certificate. Thus, in this paper, the authors try to give the information about the inspection results in easier way to understand. This information not only guarantees the owner of the vehicle to better understand the inspection results, but it also gives the opportunity to the driver to deal with the specific problem listed in the results. The methods in this paper are to transform the vehicle inspection data into the non parametric distribution to easily represent the values to the index later on. Also, example indexes are presented to the actually inspected vehicle based on the reference distribution to show the better assessment of the developed method.

• 한국태양에너지학회 논문집
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• 제32권5호
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• pp.83-93
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• 2012

This study is to perform the effect of urbanization in urban and suburban districts, and to identify regional characters of climate according to the analysis of slope at rise, and descent of temperature and globe temperature, correlation between seasonal temperature analysis, and calculation of degree hour. According to this study, the result is summarized as follows. (1) The average temperature, rated from high to low, consists of residential area, Daegu weather station, intracity, green belt, water-front green belt, and suburban. (2) At the rise and descent of temperature, the result of the slope change of in each point may be one of the useful indexes to be able to perform the regional unique thermal characteristic, including the seasonal urbanization. (3) Although there is a difference between the surface of the earth and ambient environment. The result of the correlation of temperature between summer and winter is that temperature slope in urban districts was higher than in suburban districts, and the difference of slope was unvaried among the four observations in the same city region. (4) To show objectively, regional thermal characteristics in urban and suburban districts, the exponentiation of winter degree hour and summer degree hours were checked. The result of the exponentiation is that the more artificial a region, the lower index.

• 대한교통학회지
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• 제31권4호
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• pp.18-31
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• 2013

버스전용차로는 버스교통량이 많은 간선도로에서 여객수송용량(person-carrying capacity) 증가를 통한 교통체증 완화가 목적이다. 도심의 제한된 공간에서 버스전용차로제 시행으로 인한 일반차로 감축은 교통체증을 악화시킬 수 있으므로 세심한 버스전용차로 설치 연구가 필요하다. 본 연구는 현재 버스전용차로 적합성(또는 설치 기준)을 버스교통량 및 버스이용객수에 국한하고 있는 문제점을 인식하고 7가지 지표(버스교통량, 버스노선수, 교통량/차로수, 차로수, 교차로수, 이면도로수, 노선굴곡도)를 이용하여 광주광역시 버스전용차로 적합성을 분석하여 상대적 우선순위를 결정한다. 또한 현재 운영 중인 버스전용차로 효율성 및 최적의 운영 시간대를 검토한다.

• 대한토목학회논문집
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• 제4권2호
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• pp.1-11
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• 1984

본연구(本硏究)는 평면교차점(平面交叉點)을 대상(對象)으로 하여 교통사고(交通事故)와 그 요인간(要因間)의 상호관련성(相互關聯性)을 통계적(統計的)으로 분석(分析)하고 사고예측(事故豫測)모델의 작성(作成)과 예측(豫測)모델을 이용(利用)한 교차점(交叉點)의 위험도(危險度) 평가방법(評價方法)에 대(對)한 연구(硏究)이다. 사고예측(事故豫測)모델은 주성분분석(主成分分析)에 의(依)하여 선택(選擇)된 설명지표(說明指標)를 사용(使用)하고 최량(最良)모델식(式)을 얻기 위하여 단계적(段階的) 회귀분석(回歸分析)에 의(依)하였으며 작성(作成)된 모델은 통계적(統計的)으로 유의(有意)하였다. 그리고 교차점(交叉點) 안전대책(安全對策)의 수립(樹立)은 위험교차점(危險交叉點) 추출(抽出)이 전제(前提)가 되므로 사고예측(事故豫測)모델을 이용(利用)한 위험교차점(危險交叉點)의 추출방법(抽出方法)을 제안(提案)하였다. 추출(抽出)된 위험교차점(危險交叉點)이 실제(實際)의 사고다발교차점(事故多發交叉點)과 잘 일치(一致)되었다.

• KIEAE Journal
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• 제16권5호
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• pp.29-37
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• 2016

Purpose: Indoor thermal comfort can be identified by combination of temperature, humidity, and air flow, etc. However, most thermal indexes in regard to thermal comfort are temperature dominant since it has been considered as a significant factor affecting to indoor thermal comfort The purposes of this study are to investigate indoor neutral temperature range of young Koreans with humidity perception, and to introduce a neutral temperature for temperature preference as well as temperature sensation in order to define the neutral temperature range chosen by occupants. It could be used as basic data for heating and cooling. Method: 26 research participants volunteered in 7 thermal conditions ($18^{\circ}C$ RH 30%, $18^{\circ}C$ RH 60%, $24^{\circ}C$ RH 30%, $24^{\circ}C$ RH 40%, $24^{\circ}C$ RH 60%, $30^{\circ}C$ RH 30%, $30^{\circ}C$ RH 60%) and completed subjective assessment in regard to temperature/humidity sensation and preference twice per condition in an indoor environmental chamber. Result: In RH 30%, sensation neutral temperature was $25.1^{\circ}C$ for men and $27.0^{\circ}C$ for women, and preference neutral temperature was $25.5^{\circ}C$ for men and $27.8^{\circ}C$ for women. In RH 60%, sensation neutral temperature was $23.6^{\circ}C$ for men and $25.9^{\circ}C$ for women, and preference neutral temperature was $23.4^{\circ}C$ for men and $26.3^{\circ}C$ for women. Neutral temperature increased with increasing relative humidity. Women were sensitive to humidity changes. Men expressed humidity changes as temperature variations. In most conditions, preference neutral temperatures were higher than sensation neutral temperatures, however, the preference neutral temperature for men in humid condition was lower than the sensation neutral temperature.

• 한국통신학회논문지
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• 제35권3A호
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• pp.217-224
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• 2010

본 논문에서는 3GPP의 LTE시스템에서 자동화기술 중의 하나인 기지국 구성 자동 설정 (Self-Optimization)을 위한 하드 핸드오버 알고리즘을 제안한다. 제안하는 알고리즘은 먼저 주변 셀로부터의 수신신호세기와 X2인터페이스를 통해 eNB(evolved Node-B)간의 정보 교환으로 수집된 후보 목표 셀들의 셀 부하 정보를 이용하여, 최적의 목표 셀을 선택하는 혼합형 목표 셀 선택방식과 핸드오버 성능에 영향을 주는 다양한 환경 요소들의 비용함수들에 의해서 최적의 핸드오버 히스테리시스(Hysteresis) 값을 선택하는 다중 요소 기반 능동 히스테리시스 방식으로 구성되어 있다. 본 논문에서 제안하는 알고리즘은 핸드오버 성능에 영향을 주는 요소들에 대한 정보를 바탕으로 LTE시스템에서의 기지국 운용 자동 최적화을 위한 최적화된 목표 셀과 히스테리시스 값을 선택하는 동작을 수행함으로써 핸드오버의 가장 중요한 성능인 핸드오버 실패율과 부하균형 측면에서 우수한 성능을 얻게 한다.

• 대한토목학회논문집
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• 제34권3호
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• pp.785-794
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• 2014

유역에서의 수문반응은 기후요소뿐만 아니라 토지이용, 토양, 식생 등의 여러 가지 요소에 의한 복합적 상호작용에 의해 결정된다. 따라서 유역의 수문반응을 효과적으로 파악하기 위해서는 기후요소와 다른 외부요소에 대한 특성이해가 필요하다. 본 연구에서는 수문지수(건조지수, Horton 지수)를 적용하여 유역 수문반응에 영향을 미치는 기후 및 유역 특성의 상대적 영향력을 확인하고자 하였다. 우리나라 자연 유역에서는 건조지수보다는 Horton 지수를 이용하여 유역의 수문반응을 평가하는 것이 효과적이었다. 또한 기후상태에 따라 기후요소와 유역특성이 미치는 상대적인 영향력이 달라지는데, 건조한 기후상태에서는 기후요소가 지배적으로 수문반응에 영향을 미쳤으나 기후가 습윤한 상태로 갈수록 유역특성의 역할이 상대적으로 증가하고 있음을 확인하였다.

• Fisheries and Aquatic Sciences
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• 제17권3호
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• pp.345-353
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• 2014

Copper has been widely used to control algae and pathogens in fish culture ponds. However, its toxic effects on fish depend not only on its concentration in the water but also on the water quality. A laboratory experiment was conducted to assess copper toxicity in the black rockfish Sebastes schlegeli using a panel of antioxidant enzymes, including glutathione (GSH), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) and superoxide dismutase (SOD), at different levels of copper at three water temperatures (WT, 18, 23, $28^{\circ}C$) for 4 days. After exposure to two copper concentrations (100 and $200{\mu}g/L$), GSH levels and GST activities increased significantly, depending on WT (P < 0.05) in the liver, gill, and kidney of the black rockfish. GPx and SOD activities decreased significantly with both increasing WT and copper treatment in the organs of black rockfish (P < 0.05). These changes can be seen as initial responses to temperature stress and as a sustained response to copper exposure. This also indicates that GSH and related enzymes activities were sensitive indexes to stress by toxicants such as copper. The present findings suggest that simultaneous stress due to temperature change and copper exposure can accelerate changes in enzymes activities in the black rockfish. This provides another example of synergism between environmental temperature and pollutants, which may have important implications for the survival of fish in polluted environments during seasonal warming and/or global climate change.

• 대한원격탐사학회지
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• 제36권1호
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• pp.67-81
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• 2020

The rapid climatic changes being caused by global warming are resulting in abnormal weather conditions worldwide, which in some regions have increased the frequency of landslides. This study was aimed to analyze and compare the landslide susceptibility using the Frequency Ratio (FR), Statistical Index, Weight of Evidence, Certainty Factor, and Index of Entropy (IoE) at Woomyeon Mountain in South Korea. Through the construction of a landslide inventory map, 164 landslide locations in total were found, of which 50 (30%) were reserved to validate the model after 114 (70%) had been chosen at random for model training. The sixteen landslide conditioning factors related to topography, hydrology, pedology, and forestry factors were considered. The results were evaluated and compared using relative operating characteristic curve and the statistical indexes. From the analysis, it was shown that the FR and IoE models were better than the other models. The FR model, with a prediction rate of 0.805, performed slightly better than the IoE model with a prediction rate of 0.798. These models had the same sensitivity values of 0.940. The IoE model gave a specific value of 0.329 and an accuracy value of 0.710, which outperforms the FR model which gave 0.276 and 0.680, respectively, to predict the spatial landslide in the study area. The generated landslide susceptibility maps can be useful for disaster and land use planning.