• Journal of the Korean Society of Safety
• /
• v.34 no.4
• /
• pp.6-14
• /
• 2019

There are about 38,977 CNG cars and 247 natural gas vehicle charging stations in operation in order to improve the urban air environment. With the introduction of natural gas vehicles, the atmospheric environment, which was the main cause of air pollution in the metropolitan area, was remarkably improved. However, unlike these positive effects, CNG bus accidents, which occurred more than 10 times since 2005, have caused concern among the majority of citizens using public transportation. It is necessary to make a judgment on the feasibility and future direction of CNG pressure vessel safety management that can safeguard the safety of CNG pressure vessel at the time of starting. In this study, we investigates production and use of CNG vessel, the current status of safety management of CNG bus transportation companies & charging stations and then proposes measures to prevent accident recurrence and safety management based on the actual situation investigation and analysis.

• International conference on construction engineering and project management
• /
• 2007.03a
• /
• pp.820-829
• /
• 2007

This paper presents an evaluation of feasibility studies conducted to justify investments in infrastructure projects. An analysis of a previous feasibility study for a highway construction project is presented in this paper with an emphasis on the estimates and forecasts presented in that study in order to weigh expected benefits from the project against expected costs. The forecasted numbers are compared with actual data collected during the operation phase about the usage of the facility. The comparison reveals a huge difference between estimated numbers and actual numbers. Based on the lessons learned from the analyzed case study, recommendations are presented to improve feasibility studies for infrastructure projects including: peer review of feasibility studies; before-and-after feasibility studies; and defined scope and methodology for feasibility studies. Decision makers are advised to take outcomes of feasibility studies for infrastructure projects with extreme caution as some studies may provide erroneous and misleading input to their decisions regarding investment in infrastructure projects.

• The Korean Journal of Pesticide Science
• /
• v.4 no.4
• /
• pp.35-39
• /
• 2000

In order to develop the indicators of environmental impact of pesticide, its actual usage in paddy rice was surveyed, and usage trends of individual pesticides were evaluated. The tendency of pesticide use indicated insecticide 43%, herbicide 29%, fungicide 27% and top ranking item in insecticide, herbicide and fungicide was carbofuran, molinate + pyrazosulfuran-ethyl, IBP. The usage statistics of formulation types showed GR>DP>WP>EC>FG>SP. Pesticide usage(a.i.) per hectare was 7.13kg and total usage for paddy rice was estimated at 8,387 M/T. In the result of comparison of fact-usage with pesticide consumption reported in 1998, the fitness was 94.7% for fungicide, 84.3% for insecticide, 77.8% for herbicide. The result of monitoring pesticide residue of unpolished-rice sampled from farm house of survey indicated 0.14 ppm(BPMC), 0.16 ppm(Isoprocarb), 0.17 ppm(Isoprothiolane). In case of rice straw, the residue level was 0.27 ppm(Isoprothiolane), 0.28 ppm(IBP), 0.39 ppm(Carbofuran). The residue levels of pesticides were below MRLs.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.583-587
• /
• 2006

A series of images were displayed on an OLED display placed within a digital still camera body to characterize the aging of the OLED display in a realistic environment and with an image set that matches actual consumer usage as closely as possible. The aging characteristics of the OLED display were measured and shown to meet the requirements of a digital still camera application by a wide margin.

• Electronics and Telecommunications Trends
• /
• v.16 no.6 s.72
• /
• pp.109-116
• /
• 2001

본 고에서는 18세 이상 자택에서의 인터넷 이용자를 대상으로 한 인터넷 설문조사를 토대로 국내의 인터넷 이용실태를 종합적으로 살펴 보고 그 정책적, 사업적 시사점을 고찰하고자 한다.

• International Commerce and Information Review
• /
• v.9 no.3
• /
• pp.131-149
• /
• 2007

E-tade has the potential to accelerate existing trends and introduce new ways of conducting traditional trade. The primary purpose of this research is to investigate performance factor and analyzes influence between performance of e-Trade and implementation of company. This research will be used as a basis for examining the actual results of e-Trade usage and export productivity. In order to facilitate the process, analysis began after a research prototype was created and research thesis established.

• Journal of Industrial Technology
• /
• v.30 no.A
• /
• pp.89-93
• /
• 2010

This research suggested a development of a Data Acquisition System for strain gauge sensor which enables the usage of portable device in the various engineering field that includes, a strain indicator which is frequently used in civil and mechanical engineering, and a GUI function of data acquisition device. The developed system can record 16 channels of strain gauges at a time and its resolution is over 16 bits which can be used effectively in the actual field.

• Journal of Energy Engineering
• /
• v.21 no.4
• /
• pp.435-443
• /
• 2012

The combination of space shortage and the high population density concentrated in urban areas of South Korea has resulted in the growth of large-scale high-rise residential complexes, naturally affecting water and hot water usage patterns as well. But the current designs for water and hot water supply in South Korea rely mostly on international design standards and data calculated on site due to the severe shortage of basic data in relation to actual use, which result in the frequent problem of the under-or over-design of water and hot water supply. The following study measures the hot water supplier's conditions and the user's heat usage to realize the amount of time required for hot water supply load generation and the pattern of actual use in order to create basic data for effective hot water supply facility design and maintenance.

• The Korean Journal of Pesticide Science
• /
• v.16 no.4
• /
• pp.395-400
• /
• 2012

In order to survey the actual pesticide usage, this survey was carried out on the growers of 3 plant groups, fruit vegetables, fruits and rice field, from 2009 to 2011. 390 farmers were selected from main production areas to investigate their pesticide application during the growing seasons. Input amounts per area of domestic fruit vegetables was surveyed as 11.6 kg a.i./ha for red pepper of field culture, 2.0 kg a.i./ha for red pepper of greenhouse, 2.3 kg a.i./ha for strawberry, 2.2 kg a.i./ha for watermelon, 4.8 kg a.i./ha for cucumber, 1.5 kg a.i./ha for oriental melon and 2.1 kg a.i./ha for tomato, respectively. Input amounts per area on fruits and on rice field were surveyed as 11.7 kg a.i./ha for apple, 12.5 kg a.i./ha for pear, 7.7 kg a.i./ha for peach, 4.5 kg a.i./ha for grape, 40.0 kg a.i./ha for citrus 5.4 kg a.i./ha for persimmon, and 3.46 kg a.i./ha for rice, respectively. As a result of the actual pesticide usage survey, The safety guideline for pesticide use is generally kept well by all farmers of fruits vegetables, fruits and rice.

• Journal of the Korean Data and Information Science Society
• /
• v.21 no.6
• /
• pp.1109-1115
• /
• 2010

In this paper, exact confidence interval of hyper-geometric parameter, that is the probability of success p in the population is discussed. Usually, binomial distribution is a well known discrete distribution with abundant usage. Hypergeometric distribution frequently replaces a binomial distribution when it is desirable to make allowance for the finiteness of the population size. For example, an application of the hypergeometric distribution arises in describing a probability model for the number of children attacked by an infectious disease, when a fixed number of them are exposed to it. Exact confidence interval estimation of hypergeometric parameter is reviewed. We consider the performance of exact confidence interval estimates of hypergeometric parameter in terms of actual coverage probability by small sample Monte Carlo simulation.