PURPOSES : There are generally various driving behaviors in toll collection areas, including lane changing, merging and diverging, and other behaviors. Because of these behaviors, accident risk and traffic congestion may occur. To mitigate these problems, multi-lane electronic toll collection systems have been developed with a high-speed limit of 80 km/h. This study was conducted to investigate travel speed changes and effects through multi-lane electronic toll collection systems with a high-speed limit.
METHODS : Traffic simulations were conducted using VISSIM. Before conducting simulations, driving behavior around the toll collection areas was observed, and field data were collected based on drones for peak and non-peak hours. In addition, safety effect evaluations were conducted based on conflict analyses using the SSAM software.
RESULTS : Through multi-lane electronic toll collection systems with a high-speed limit, the travel speed on the toll collection area was increased, and traffic operational efficiencies were identified. However, different speed variations were produced as observation locations in toll collection areas. Speed variations were mitigated at most locations except the area within the tollbooth because of the high speed limit for multi-lane electronic tollbooth.
CONCLUSIONS : It was important to manage lane-changing activities, and this may influence traffic operational effects. Safety effects were also identified through conflict analyses.
Temperature-dependent development models for Hydrochara affinis were built to estimate the ecological parameters as fundamental research for monitoring the impact of climate change on rice paddy ecosystems in South Korea. The models predicted the number of lifecycles of H. affinis using the daily mean temperature data collected from four regions (Cheorwon, Dangjin, Buan, Haenam) in different latitudes. The developmental rate of each life stage linearly increased as the temperature rose from 18°C to 30°C. The goodness-of-fit did not significantly differ between the models of each life stage. Unlike the optimal temperature, the estimated thermal limits of development were considerably different among the models. The number of generations of H. affinis was predicted to be 3.6 in a high-latitude region (Cheorwon), while the models predicted this species to have 4.3 generations in other regions. The results of this study can be useful to provide essential information for estimating climate change effects on lifecycle variations of H. affinis and studies on biodiversity conservation in rice fields.
기존에 주로 논 수서생물의 채집을 위해 사용된 방형구법과 뜰채법은 높은 노동력을 요구했기 때문에 광범위한 지역을 대상으로 한 모니터링이 어려웠다. 이 연구는 논 수서 생물을 보다 신속하게 채집할 수 있는 수중트랩을 사용하여 지역 및 시기별 논 수서생물의 군집 조성을 확인하였다. 수 중트랩은 논을 대표하는 수서생물 중 환경 변화를 지표하거나 수조류의 먹이가 되는 이동성이 높은 종이 포함된 분류 군을 채집하는 데 유용했다. 사과우렁이과 (Ampullariidae), 미꾸라지과 (Cobitidae), 물벌레과 (Corixidae), 물방개과 (Dytiscidae), 물땡땡이과 (Hydrophilidae), 물달팽이과 (Lymnaeidae) 등 15개 분류군은 논 수서생물 군집 조성을 결정했다. 주요 분류군 중 환경 교란에 강한 깔다구과 만이 논 수서생물 군집의 시기 변화를 대표했다. 인위적인 영향에 민감한 사과우렁이과, 물땡땡이과 그리고 물방개과는 지역 별로 분포가 상이했다.
본 연구는 국가중요농업유산으로 지정된 울릉도 (울릉도 화산섬 밭 농업) 나리분지와 통구미지역의 지표배회성 무척추동물 군집의 특성을 확인하기 위해 수행되었다. 서식지 형태를 작물재배지역, 산림지역, 중간 경계지역으로 나누어 서식지 형태별로 지표배회성 무척추동물을 채집하였다. 채집은 함정 트랩을 이용하였고 채집된 지표배회성 무척추동물은 자기조직화지도를 이용하여 군집 특성을 규명하였다. 자기조직화지도를 통해 총 4개의 cluster로 나누었으며, cluster II에는 통구미지역에서 채집된 지표배회성 무척추동물 군집만이 속하는 특성을 확인할 수 있었다. 나리분지 (cluster I, III, IV)와 비교하여 통구미지역 (cluster II)은 울릉도에서 흔히 확인되는 산간지역 경작지를 밭으로 개간하여 이용하는 지역으로 울릉도에서 흔히 관찰되는 지형적 특성을 가지고 있다. 이러한 통구미지역은 평지의 형태를 가지는 나리분지 지역과는 달리 급경사의 특성을 나타내기 때문에 다른 군집 특성이 나타난 것으로 판단된다. 본 연구결과는 국가중요농업유산으로 선정된 울릉도지역의 생물상에 대한 기초자료와 지표배회성 무척추동물 군집 특성에 관한 정보를 제공하여 농업 환경 보전 및 생물다양성 유지를 위해 활용될 것으로 기대된다.
The need for an efficient sampling technique to collect aquatic organisms has risen with the increase of interest in rice paddy fields, which have been recognized as important ecosystems supporting biodiversity. In the present study, a submerged funnel trap used with the assistance of attracting agents (fish meal and chemical light) was designed as an easy, objective and quantitative tool for collecting aquatic organisms in the rice paddy fields. The preference for collecting aquatic organisms as a means for attracting agents was analyzed using a generalized linear mixed model. Also, based on the data of previous research, we compared the community composition of the aquatic macroinvertebrates, which were collected using the quadrat method, and newly designed submerged funnel traps, by analyzing non-metric multidimensional scaling. The results showed that the catching efficiency of 18 of the total 65 taxa was affected by the attracting agents. 12 taxa including Pomacea canaliculata, Hippeutis cantori, Austropeplea ollula, Erpobdella lineata, Ostracoda spp. Branchinella kugenumaensis, Hydaticus grammicus, Rhantus pulverosus, Chironomidae spp., Rana nigromaculata, Cobitidae spp. etc., favored fish meal and 6 taxa including Ischnura asiatica, Coenagrionidae spp. Sternolophus rufipes etc., were attracted by chemical light. The submerged funnel trap used as a measurement tool for biodiversity was less applicable than the quadrat method; however, it was more effective for the selective collection of specific taxa. We expect that this newly designed trap can be a simple and quantitative method for collecting aquatic organisms, and could be used for long term and extensive surveys in rice paddy fields in the future.
Sewer condition assessment involves the determination of defective points and status of aged sewers by a CCTV inspection according to the standard manual. Therefore, it is important to establish a reliable and effective standard manual for identifying the sewer defect. In this study, analytic reviews of the CCTV inspection manuals of the UK, New Zealand, Canada and South Korea were performed in order to compare the defect codes and the protocols of condition assessment. Through this, we also established the standardized method for defect code and revised the calculation method of assigning the condition grade. Analyses of the types and frequencies of sewer defects that obtained by CCTV inspection of 7000 case results, showed that the joint defect and lateral defect were the most frequent defects that occurred in Korea. Some defect codes are found to be modified because those did not occur at all. This study includes a proposed new sewer defect codes based on sewer characteristics.
본 연구의 목적은 신기술을 바탕으로 급속히 성장한 신재생에너지 분야 기업의 재정적 어려움을 계량적으로 파악하고 부도위험과 지속가능성을 예측하는 것이다. 태양광 및 풍력기업으로 대표되는 신재생에너지산업은 신생기업이 많은 분야이며, 또한 한국의 현실상 중소기업이 많은 영역이라 start-up기업, 중소기업의 연구란 관점에서도 의의가 있다. 기업의 부도가능성 측정에 관한 연구는 재무비율을 이용한 초기모형 구축을 통한 분석, 기업의 지배구조 분석을 통한 모형분석, 위험과 생존요인을 이용한 분석 등이 주를 이룬다. 본 연구의 분석방법으로 많은 국가에서 이용되고 있는 ‘Altman Z-score’를 채택하였다. 분석 표본은 한국의 태양광과 풍력분야 상장기업 121개 이며, KIS-VALUE Data를 중심으로 수집, 분석하였다. 분석 대상기간은 2006년부터 2011년이다. 알트만 스코어로 분석한 결과, 태양광과 풍력기업 중에서 ‘경계 태세(on-alert)’로 분류되어 부도위험에 크게 노출된 기업은 38%,’예의주시(watch)’가 필요한 기업은 38%로, 합하여 76%가 지속가능성에 의문을 받는 기업으로 측정되었다. 신생기업의 경우 순수한 중소기업이 대기업군에 속한 기업보다 지속가능성이 낮았다. 기업규모가 대체적으로 큰 풍력분야 기업과 규모가 작은 태양광분야 기업의 부도위험을 비교한 결과, 풍력기업군의 부도위험이 다소 높게 나타났으나 유의적이지는 않았다. 결과적으로 Altman Z-score의 유용성이 한국의 신재생에너지 산업군 분석에도 검증되었다고 할 수 있다. 본 연구는 신성장산업인 태양광, 풍력기업의 상당수가 부도위험에 직면하였다는 것을 실증적으로 보여준 점에 의의가 있다. 또한 신생 start-up 기업의 연구, 중소기업과 대기업군 기업과의 비교연구를 진전시켰다는 점에 의미가 있다.
The purpose of this study is to measure the cost-benefit of a road construction project in Vietnam through international development cooperation, which includes private grants and Official Development Assistance(ODA). In developing countries, it is difficult and costly to use data on markets, the CVM(Contingent Valuation Method) to measure the WTP(Willingness-to-Pay) as the benefits of road construction are used. A total of 232 villagers in 16 villages of Lao Cai Province in Northern Vietnam have been surveyed. It is found that the Benefit-Cost Ratio(B/C) in all 3 models are found to be well over 1.0, ranging from 2.8 to 3.64 with the discount rate of 0.06. These BC ratios imply the road construction project in Lao Cai can be justified. Also, it is found that the shortened travel time is the most relevant factor for WTP among direct benefits and the enhanced academic achievement of the children is the most relevant factor among indirect benefits, due to easier and faster access to schools, which in turn increase the school attendance rate. The result of this study can be used to justify other similar projects in Vietnam, even though the benefits may have to be reassessed in other countries.
The rural areas are large residential space with fewer people than urban areas. That is why they are vulnerable to social services such as health care and security. This research analyzed the vulnerability of emergency relief service in rural village through text mining and the weighting value have been calculated. Based on the calculated statistics data, the police facilities are the most important, While the fire fighting and hospital facilities are important as well. In addition, the distance from the emergency relief service facility to the rural village was confirmed by using Open API. By combining these results, The vulnerable areas of the rural villages and the emergency relief service facilities were calculated and classified into 5 levels. For rural areas, the 1st class will have 33 places, following by 1,179 in 2nd class, 199 in 3rd class, 17 in 4th class and 8 in 5th class. Hence in order to further supplement the vulnerable areas to emergency relief service in villages, geographical relocation and policy approach of emergency relief service facilities are necessary.
This study is to estimate the circuity factors which can be used to assess for public facilities accessibility and analyze traffic in the area. We set the range of the administrative districts by Si‧Gun‧Gu unit and Eup‧Myeon‧Dong unit (more subdivided unit than Si‧Gun‧Gu unit). The average circuity factor in Si‧Gun‧Gu unit is 1.364 (maximum 2.953 and minimum 1.711). The region indicated the highest value of circuity factor is wando-gun in jeollanam-do, which area consists of 4 island and is connected to the bridges. Having to use the bridges for using public facilities hinders its accessibility. In the case of Eup ‧ Myeon ‧ Dong unit, the average circuity factor is 1.353 (maximum 2.950 and minimum 1.154). The region indicated the highest value of circuity factor is buksan-myeon in chuncheon-si, Gangwon-do. This region also has to use bridges for using public facilities because there is the largest lake, called Soyangho. This circuity factor is used to analyze the location of public facilities and assess vulnerability of accessibility. And also the factor can be applied to some policies, such as rural public service planning based on spatial big data.
Public transportation is public service that is contributed to the convenience of the public. However, opportunity for public services in rural areas is weaker than the chance in urban areas. The purpose of this study is to evaluate accessibility of various public facilities using public transportation. To evaluate the accessibility, we calculate the various time from community center to the nearest bus stop, walking time, riding time in bus, and waiting time for transfer. The results of this study ares as follows; (1) Villages occupy 19.8% in rural areas that walking time from community center to the nearest bus stop takes over 10 minutes in integrated Chungju-si; (2) The average speed is 21.9 km/hr estimated to departure and arrival time of bus route; (3) The accessibility time from community center using the average bus speed takes 15.43 minutes to public facilities, 35.15 minutes to emergency center, 8.70 minutes to medical center, 9.70 minutes to elementary school, 16.26 minutes to middle school, and 22.61 minutes high school; (4) The transfer time of public transportation takes 13.46, 21.96, 10.48, 7.78, 11.11, 16.10 minutes to public facilities, emergency center, medical center, elementary school, middle school, and high school, respectively; (4) Traffic accessibility using bus vehicles in the East and South Chungju-si is lower than areas in the West and North Chungju-si. Some villages surrounding public offices (eup-myeon office) which have a high density of population, indicate a high traffic accessibility.
A disaster can be defined in many ways based on perspectives, in addition, its types are able to classify differently by various standards. Considering the different perspectives, the disaster can be occurred by natural phenomenon that is like typhoon, earthquake, flood, and drought, and by the accident that is like collapse of facilities, traffic accidents, and environmental pollution, etc. Into the modern society, moreover, the disaster includes the damages by diffusion of epidemic and infectious disease in domestic animals. The disaster was defined by natural and man-made hazards in the past. As societies grew with changes of paradigm, social factors have been included in the concept of the disaster according to new types unexpected by new disease and scientific technology. Change the concept of social disasters, Ministry of Public Safety and Security (MPSS) has provided the regional safety index, which measures the safety level of a local government. However, this regional safety index has some limitation to use because this index provides the information for city unit which is a unit of administrative districts of urban. Since these administrative districts units are on a different level with urban and rural areas, the regional safety index provided by MPSS is not be able to direct apply to the rural areas. The purpose of this study is to determine the regional safety index targeting rural areas. To estimate the safety index, we was used for 3 indicators of the MPSS, a fire, a crime, and an infectious disease which are evaluable the regional safety index using an accessibility analysis. For determining the regional safety index using accessibility from community centers to public facilities, the safety index of fire, crime, and infectious disease used access time to fire station, police office, and medical facility, respectively. An integrated Cheongju, targeting areas in this study, is mixed region with urban and rural areas. The results of regional safety index about urban and rural areas, the safety index in rural area is relatively higher than in the urban. Neverthless the investment would be needed to improve the safety in the rural areas.
This study carried out evaluation of vulnerability in accessability and functionality using road network that was extracted from Intelligent Transportation System(ITS) and digital map. It was built in order to figure out accessability that locational data which include community center, public facilities, medical facilities and highway IC. The method for grasping functionality are Digital Elevation Model(DEM) and land slide hazard map provided by Korea Forest Service. The evaluation criteria for figure out accessability was set to related comparison of average time in urban area. Functionality value was calculated by the possibility of backing the vehicle possibility of snowfall and landslides. At last, this research computed weighting value through Analytic Hierarchy Process (AHP), calculated a vulnerable score. As the result, the accessability of rural village came out that would spend more time by 1.4 to 3.2 times in comparison with urban area. Even though, vulnerability of the road by a snowfall was estimated that more than 50% satisfies the first class, however, it show up that the road were still vulnerable due snowing because over the 14% of the road being evaluated the fifth class. The functionality has been satisfied most of the road, however, It was vulnerable around Lake Daechung and Piban-ryung, Yumti-jae, Suriti-jae where on the way Boeun. Also, the fifth class road are about 35 km away from the city hall on distance, take an hour to an hour and a half. The fourth class road are about 25 km away from the city hall on distance, take 25 min to an hour. The other class of the road take in 30 min from the city hall or aren't affected of weather and have been analyzed that a density of road is high. In A result that compare between distribution and a housing density came out different the southern and the eastern area, so this result could be suggested quantitative data for possibility of development.
In this study, we try to quantify resident's conflict by rural development project based on previous researches about community capacities required for residents and social networks in rural village for suggesting efficient project model. we analyzed conflict elements in six category such as 'conflict in residents', 'conflict in residents and leaders', 'conflict in leaders', 'conflict in villages', 'conflict in development fund', 'conflict in village by common income project'. These results also analyzed by personal background(age, role, education, income) of respondent in questionary survey. Results show that 'conflict in residents and leaders', 'conflict in leaders', 'conflict in development fund' are perceived differently by age, role, education, and income in 5% significance level. Especially, relatively young age(below 40 years old) expressed clearly about conflict and high scored in item of 'residents and leaders'. Regression model show statistical significance(F=39.807, P=0.000) in influence relation analysis of conflict, network, leadership, and project fund. In this model, network β=-0.237, leadership β=-0.375, project fund β=-0.000 show network and leadership have negative relation to conflict but project fund is difficult to find relation with conflict. In this study, we defined social vulnerability using conflict, network, and leadership and verified the vulnerability of rural village applying regional community capacity in analysis results; vulnerability increased by the size of region and show inverse correlation to future vision of residents.
The purpose of this study was to develop survey tools for diagnosis of capacity levels in business promotion of rural residents when performing a rural development project of a regional unit. The cases of previous studies were analyzed to select community capacity indicators related to a rural development project. Five indicators were derived : social capital, consciousness of participation, community spirit, and leadership. Based on the five indicators, measurement items of various capacities were selected and 54 survey items were selected through evaluation of experts twice. The pilot tests were conducted and targeted at Jeonnam song ho-jung village and Gyeongnam Haegeumgang village to identify derived survey items. In addition, descriptive statistic analysis and reliability analysis were conducted. As a result, survey items were corrected by reducing 10 items of the total 54 items. This results showed that using this tool could help us understand capacity levels of rural residents.
Self-sufficiency rate of food in South Korea is almost at the lowest level among OECD countries, and the decrease tend of farmland is expected to be continued. In this situation, the government has been revised the target self-sufficiency rate of food, and carried forward various policies in order to achieve it. One of those policies is the restoration business of idle farmland which is planned to carry forward after 2015. This study set up indicators evaluating effective use of idle farmland, and tried to apply in the field before carrying forward restoration business. The result of this study may be summarized as follows. First of all, it reset an evaluation indicator that was based on the evaluation indicator developed in order to set application directions of idle farmland. Next, it selected 30 idle farmlands with reset evaluation indicator among 11,635 which were inspected nationwide in 2012. Before applying indicator, it measured the condition of recycling such as accessibility of farmland, condition of irrigation and drainage system, land state, and surroundings by field investigation. Then, it calculated composite score in each target area through applying indicators, and verified the indicator by comparing calculated result with the one which was decided from field investigation. Finally, it carried out field investigation, correct and upgrade some problems of the standard of score calculation that was found during applying previously set evaluation indicator to target area, and established the final standard of calculation for evaluation indicator.
The greenhouse gas emission according to the energy consumption is the cause of global warming. With various climates, it is occurs the direct problems to ecosystem. The various studies are being to reduce the carbon dioxide, which accounts for more than 80% of the total greenhouse gas emissions. In this study, estimate the carbon usage using potential biomass extracted from forest type map according to land-use by satellite image, and estimate the amount of carbon dioxide, according to the energy consumption of urban area. The CO2 adsorption is extracted by the amount of forest based on the direct absorption of tree, the other used investigated value. The CO2 emission in Jecheon was 3,985,900 TCO2 by energy consumption. At the land cover classification, the forest is analyzed as 624,085ha and the farmland is 148,700ha. The carbon dioxide absorption was estimated at 1,834,850 Tons from analyzed forest. In case of farmland, it was also estimated at 706,658 Tons.
지하에 매설용 하수관거 자재에 대한 누수를 체크할 수 있는 장비로는 수밀시험 방법이 많이 사용되어 왔다. 공기압 시험을 활용한 누수시험방법은 수밀시험의 문제점을 보완할 수 있으며, 자연상태 및 대기중에 있는 공기를 활용하여 공기압으로의 대체를 통하여 훨씬 더 효율적이면서도 친환경적인 방법으로의 유도 및 국가 시방서의 개정을 통한 효과적인 누수시험방법을 제시하고자 하는 노력은 계속되어왔었던 것도 사실이다. 수밀시험방법의 문제점으로는 용수확보 문제, 사용 후 처리수의 문제, 펌핑 비용 및 인력의 과다한 투입문제 등이 늘 지적되어왔다. 이를 개선하기 위한 일환로 공기압 시험방법은 관로 내부로 공기를 형성하여 배기되는 시간을 모니터링 하고 적정 압력상태에서 밸브를 폐쇄시킨 다음 일정한 압력상태에서의 변화를 모니터링함으로서 대상관로의 수밀검사를 수행하는 기술이다.