• Journal of Korea Water Resources Association
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• v.47 no.10
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• pp.891-906
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• 2014

This study suggests the hedging rule of MIP (Mixed Integer Programing) in counting the risk evaluation criteria of the objective function and constraints in order to provide the optimum operating rule in reservoir system as constraining water shortage as much as possible which may happen in the downstream control point of water supply in the aspect of water system management. The proposed model is applied to the Han-river reservoir system for two testing periods (Case I: Jan. 1993~Dec. 1997, Case II: Jan. 1999~Dec. 2003). The model based on the hedging rule with trigger volume, estimated in this study shows that in Case I, the monthly minimum discharge was $310.6{\times}10^6m^3$ in the single operation, $56.3{\times}10^6m^3$ in the joint operation, and $317.5{\times}10^6m^3$ in the hedging rule and also, in Case II, the monthly minimum discharge was found to be $204.2{\times}10^6m^3$ in the single operation, $111.2{\times}10^6m^3$ in the joint operation, and $243.7{\times}10^6m^3$ in the hedging rule. In conclusion, the hedging rule, proposed in this study can decrease vulnerability while guarantees reliability and resiliency.

• Journal of the Korea Concrete Institute
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• v.16 no.1 s.79
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• pp.70-78
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• 2004

Although set accelerating agents are used generally in New Austrian Tunneling Method, the standards for test methods and quality of set accelerating agents are not prescribed domestically. In this study, the proprieties of the various standards and the characteristics of set accelerating agents for shotcrete were evaluated. The alkali contents of set accelerating agents based on silicate, aluminate and cement were higher than those of alkali-free ones. From the result, it is thought that the quality control of aggregate should be enhanced and that the number of test cycle of alkali-aggregate reaction should be increased. The setting times of cement paste with set accelerating agents based on silicate and alkali-free ones were different largely with mixing methods. Compressive strength of mortar with set accelerating agents based on silicate, aluminate and cement at one day satisfied the specifications of Korea Concrete Institute. However, the strength ratio compared to control mix at 28 days showed as $50{\~}65\%$ except for the alkali-free set accelerating agents. As a results of setting time and strength test, the establishment of domestic standards that can reflect the characteristics of materials and construction methods of tunnels and that can increase quality of set accelerating agents is required immediately.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.3
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• pp.186-194
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• 2014

Purpose: Process management is the activity which manages all procedure of construction by representing visually interrelation of operation or sequence setting. The purpose of this study was for reducing treatment period and higher efficiency of treatment through application of PERT/CPM (Program Evaluation & Review Technique/Critical Path Method) in dental clinic. Materials and methods: The patients were selected for study who needed more than 2 departments' cooperation for prosthodontic treatment in Wonkwang Dental University Hospital. Control group is composed of the patient's whole treatment plan, treatment period, numbers of hospital visit, treatment costs, treatment results. On the other hand, experiment group contains the patient's virtual treatment data based on PERT/CPM technique. We applied PERT/CPM in operation analysis. Results: Treatment period, numbers of hospital visit was decreased as 18.1% and 15.3% when we applied operation analysis based on charts. Also treatment cost in experiment group was 0.9% economized compared with control group's treatment cost. Conclusion: Application of PERT/CPM in dental clinic can achieve reliable treatment and reduced treatment period and establish plan of minimum treatment cost.

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.32-42
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• 1995

Cultivation using rain shelter is very popular in summer because rain shelter has a simple structure using less materials than any other regular greenhouse. Although it has a main advantage of easy construction in terms of labour, time and cost, it has some disadvantage of poor ventilation and rain fall inflow. Therefore, the rain shelters being able to overcome the problems, to some extent, are necessary to propagate for practical purpose. Three characteristic types of rain shelter were analyzed using measured and simulated environment data. Type 1 was a conventional type with an arched roof, and Type 2 and Type 3 were improved ones which were designed to have three arched roofs and three sawtooth like roofs with the openings for ventilation, respectively. The distribution of inside temperature measured was relatively uniform in Type 2 and 3 by the natural ventilation through the openings of the roof compared to Type 1 which had no openings. The relative light transmittance measured in Type 2 and 3 showed lower than that in Type 1, which suppressed the rise of inside temperature, For more accurate comparison, the differences between inside and outside temperatures to various wind speeds were calculated by the model. The difference in Type 1 was the greatest at lower wind speed below 1 ㎧, that is, the highest in inside temperature, but decreased rapidly as wind speed increased above 1 ㎧. Measured temperatures generally showed the same trends as calculated ones by the model. As a whole, the improved rain shelters(Type 2 and 3) showed better performance than the conventional one in ventilation as well as inside temperature.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.287-295
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• 2015

This study was conducted to find the suitability site selection for the construction of Saemangeum horticulture complex taking into account cost-effective environmental management by analyzing and comparing meteorological conditions. The study sites were regions around the Saemangeum area in which the development of an industrial complex extending 28,300 ha is planned. We collected meteorological data in 12 candidate sites and established a rating scheme and thematic maps. We selected ten themes by consulting experts using a questionnaire. Selected ten themes is Summer, 20 days max. temp. mean, Winter, 20 days min. temp. mean, Summer, 90 days temp. mean, Winter, 90 days temp. mean, Year-round, max. wind velocity, Year-round, wind velocity mean, Winter, 90 days solar radiation mean, Year-round, number of foggy days, Year-round, 1 day max. rainfall and Spring. 90 days humidity mean. And we set ratio-based weights for the evaluation parameters.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.185-191
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• 2009

The construction of experimental greenhouses, operating test, and analysis on variation of different environment factors were conducted to provide fundamental data for design of Korean style air-inflated double-layer plastic greenhouse. The development of technology of attaching plastic to the structure and fasteners to be able to keep airtight was required in order to maintain proper static pressure in air space of double layer coverings. The insulation effect of air inflated greenhouse was better than conventional type. The temperature of arch type roof was greater about $2^{\circ}C$ than peach type roof in air inflated greenhouse. It was recommended that the plastic should be attached at the edges without clearance length in order to ease installation and raise airtightness of double layer coverings. The transmittance of arch type roof was greater than peach type in air inflated one span greenhouse. The transmittance of air inflated greenhouse was greater than conventional type due to frame ratio and distance between double layers in three span greenhouse. The condensation occurred on conventional type greenhouse was more than air inflated type. It was required to examine for a long time in order to analyze it quantitatively.

• Journal of Preventive Medicine and Public Health
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• v.38 no.2
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• pp.125-131
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• 2005

Injury has recently become a major world-wide health problem. Injury related deaths occur in many actively working young people and produce major social and economical losses. However health related specialists do not recognize the importance of injury and there have not been many studies related to this problem. This research studied the trends of injury related research in Korea, mortality rate and prevalence rate, socio-economical losses and control in Korea and out of the country, based on literature from Korea and without such as statistical yearly reports on causes of deaths and OECD health reports, as well as WHO web sites. Studies in Korea about injury were very few, with 9 in the 1960's, 5 in the 1980's, 4 in the 1990's and 5 in 2000's. Mortality rate of injury was higher in Korea than in England, USA or Japan, especially in car accidents, suicide and falls. In Korea, the yearly trends in mortality rates were highest in car accidents but those rates are falling, suicide is steadily rising, with highest rate in 2003. Falls is in second rank with no change in rates. In 2003, the ten causes of death in Korea were suicide in 5th rank, transport accidents in 7th rank, and falls in 10th rank. Considering age groups, in the teens, transport accidents were 1st rank, in the 20's and 30's, suicide was 1st rank, and although there were some differences, falls, drowning, assault, fire were in the top 10. Prevalence rates of injury could not be known, but in 2001, according to the National Health and Nutrition Survey, lifelong injury was 10%, and yearly major injury was 1.3%, major injury for two weeks was 0.1%, and minor injury was 10%. In other foreign countries, injury has become to be recognized as a major health related problem, and much programs are being set up to reduce injury related deaths and injuries. WHO is putting much effort in prevention of violence and transport accidents, and in the USA, Canada and Europe, there are injury surveillance systems. Recently, as suicide is increasing rapidly and providing much problems, each country are managing suicide prevention programs. In Korea, Ministry of Construction and Transportation is managing and guiding the policies for prevention of transport accidents. In September of 2004, the Ministry of Health and Welfare has set up a 5 year plan of suicide prevention.

• 전자공학회논문지 IE
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• v.46 no.4
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• pp.1-7
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• 2009

The final goal of ITS and ETC will be to improve the traffic efficiency and mobile safety without new road construction. DSRC system is emerging nowadays as a solution of them. China DSRC standard which was released in May 2007 has low bit rate, short message and simple MAC control. The DSRC system users want a long lifetime over 1 year with just one battery. In this paper, we propose the SoC of very low power consumption architecture. Several digital logic concept and analog power control logics were used for very low power consumption. The SoC operation mode and clock speed, operation voltage range, wakeup signal detector, analog comparator and Internal Voltage Regulator & External Power Switch were designed. We confirmed that the SoC power consumption is under 8.5mA@20Mhz, 0.9mA@1Mhz in active mode, and under 5uA in power down mode, by computer simulation. The design of SoC was finished on Aug. 2008, and fabricated on Nov. 2008 with $0.18{\mu}m$ CMOS process.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.1
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• pp.25-31
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• 2012

The frequency and abundance of jellyfish, presumably related with climate change, fisheries overexploitation, marine pollution including land reclamation and dyke construction, are increasing worldwide. This feature has attracted interest and concerns from general public and public officials, and government is seeking how the damages could be prevented or reduced down. Korean government, having recent huge blooms of jellyfish, engaged in reducing and/or countermeasuring jellyfish damages. Korean research themes include ecology and physiology of blooming jellyfish species, understanding of the blooming mechanism, and focus on the eradication of blooming jellyfish, without governmental integrative management plan. EU is undertaking scientific projects focused on understanding of the mechanism and control of jellyfish blooms, and establishment of an integrative management. In USA, government has established the code on jellyfish management for conserving and protecting the fish and shellfish resources and one of its department is specially assigned to monitor jellyfish appearance, undertake research, and prepare management plan. Japan also assigned a department and research institute for jellyfish research. Their main interest is to predict jellyfish drifting and mass bloom. Compared to Korea, USA, EU and Japan emphasize integrative management that includes ecological understanding, public education and outreaches, communication and control, if possible, of jellyfish blooms, based on scientific data. We suggest then, 1) establishment of an integrative scientific system consisting of policy and scientific experts to prepare inter-ministrial integrative management plan to effectively combat jellyfish blooms and to maximize the scientific result; 2) concept change from harmful to exploitable marine animal in policy making and research; and 3) active education and information service for people. We expect that these suggestions can be useful for jellyfish management and policy making on another harmful marine organisms.

• Journal of the Korean GEO-environmental Society
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• v.15 no.9
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• pp.77-85
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• 2014

Recently, the National Emergency Management Agency of Korea has been operating the National Disaster Management System. Nevertheless, there are numerous difficulties in systematic controlling the steep slope DB promptly, because the system's functions in input and control for steep slope information are merely simple. Futhermore, the hazard degrees of steep slope lands nowadays have risen suddenly in accordance with the increase rate of large scale landslides such as the landslide cases of Umyeonmountain, Chuncheon province and others or sever rain storm cases. these lead to rapid increases in frequencies of nature disasters nationally. therefore, it is needed to develop the GIS-based integrated management system for steep slope information in order to manage disasters in advance or high-degree control. This study shows the national GIS-based integrated management system to prevent the disasters that caused by steep slope lands. The integrated management system developed in this study consists of surface information input modules, realtime DB liaison modules of integrated underground information, V-world background map-based GIS, integrated management system for steep slope information user modules, realtime liaison interface modules designed for utilizing steep slope information. Also, tests about stability of data storage, system stability and consistency of processing speed were performed.