• Journal of Environmental Science International
• /
• v.10 no.1
• /
• pp.21-25
• /
• 2001

The Keum river has been utilized for drinking water supply of several city including Kunsan city and is deepening pollution state due to numerous municipal and industrial discharges. The concentration BOD in river is affected by the organic loading from a tributary and the algae biomass that largely happen to under eutrophication state. In the eutrophic water mass such as the Keum river, the autochthonous BOD was very important part for making a decision of water quality management, because it was accounted for majority of the total BOD. The predict of water quality has important meaning for management of water quality pollution of the Keum river. The purpose of this study will manage and predict water quality of the Keum river using QUAL-2E model considering the autochthonous BOD. The estimation of autochthonous BOD represented that the relationship between BOD and chlorophyll a. The regression equation was shown to be autochthonous BOD=$\beta$(sub)5$\times$chlorophyll a. The results of this study may be summarized as followed; The QUAL-2E model was calibrated with the data surveyed in the field of the study area in June, 1998. The calculated value by QUAL-2E model are in good agree to measured value within relative error of 7.80~20.33%. Especially, in the case of the considering autochthonous BOD, the calculated value of BOD were fairly good coincided with the observed values within relative error of 15%. But the case of not considering autochthonous BOD, relative error of BOD was shown to be 43.2%. In order to attain II grade of water quality standard in Puyo station which has a intake facility of water supply, we reduced to the pollutants loading of tributaries. In the case of removed 100% BOD of tributaries, the BOD of Puyo station was 4.07mg/$\ell$, belong to III grade of water quality standard. But in the case of removed 88% nutrient of tributaries, it was satisfied to II grade of water quality standard as below 3mg/$\ell$ of BOD. For estimation of autochthonous BOD in Keum river, we are performed simulating in accordance with reduction of nutrient load(50~100%) under conditions removal 90% organic load. Occupancy of autochthonous BOD according to nutrient loading reductions were varied from 25.97~79.51%. Occupancy of autochthonous BOD was shown to be a tendency to increasing in accordance with reduction of nutrient loading. Showing the above results, the nutrient that one of the growing factor of algae was important role in decision of BOD in the Keum river. For the water quality management of the Keum river, therefore, it is necessary to considering autochthonous BOD and to construction of advanced sewage treatment plant for nutrient removal.

• Korean Journal of Social Welfare
• /
• v.69 no.1
• /
• pp.33-57
• /
• 2017

This study examines the effect of working conditions for care workers on the care quality in long-term care facilities, particularly the coexisting perspective on publicness and the marketization of Long-term care services in South Korea brings about. Prior studies have not identified a causal relationship between working conditions and the care quality, only explained cause of a low-wage labor market and low productivity of social services. Theoretical relevance of working conditions and service quality on Long-term care in Korea is to view from a integrated care model by Daly and Lewis(2002). A nonproportional stratified sampling procedure was used to consider Long-term care facility's ownership. A merged dataset combining surveys from 248 Long-Term Care facilities and online resources from NHIC administrative was used and analyzed by multiple regression. The analysis results is showed as follows. Overall, organizations with better working conditions, having higher wage, having greater a fringe benefit, being skills development and training are likely to have good care quality in each area. This research shows that the working conditions, rewards and support to care workers of organizational culture in the normative dimension beyond the minimum standard on labor market policy and evaluation system by government regulations have a positive impact on Long-term care quality.

• Journal of Korean Society of Forest Science
• /
• v.101 no.2
• /
• pp.251-258
• /
• 2012

This study was conducted to analyze field inspection results of erosion control facilities within national forests and to suggest maintenance and management plan of erosion control facilities. The objects amounted to a total of 1,628 locations, comprising 308 erosion control dams and 1,320 erosion control areas (1,269.05 ha). The field inspections were conducted during March-June each year. The erosion control dams inspected were constructed during 1991-2005, with 96.4% of them, or 297 dams, constructed in or after 2000. The erosion control areas were constructed during 1986-2005, with 68.6% of them, or 903 areas, constructed in or after 2000. As for erosion control dams, there were 205 concrete erosion control dams and 68 concrete with boulder pitching erosion control dams, respectively, with 296 out of a total of 308 erosion control dams in a good condition. As for erosion control areas, there were many erosion control structures using stone masonry works and gabions, with 1,245 out of a total of 1,320 (94.3%) erosion control areas in a good condition. Overall, erosion control facilities within national forests were in a good condition, amply fulfilling their functions. As for erosion control facilities in a bad condition, they must be made to accomplish the goals of erosion control works through supplementation and repairs without fail. In addition, for the systematic maintenance and management of existing erosion control facilities and erosion control facilities constructed in the future as part of erosion control works, the construction of an erosion control facility management system is urgently needed.

• Journal of the Korean Data and Information Science Society
• /
• v.26 no.1
• /
• pp.111-121
• /
• 2015

Until now, the operation of community welfare centers for people with disabilities has brought a positive or a generous awareness. Nevertheless, in order to obtain a wide range of welfare outcomes efficiently, the imperative step in rehabilitation researches is to determine whether reasonable and scientific services are being provided to people with disabilities in rehabilitation centers. The purpose of this study was to analyze efficiency and productivity of 176 community welfare centers for people with disabilities. As a result, average technical efficiency for community welfare centers for people with disabilities was 0.4488; pure technical efficiency and scale efficiency was 0.6040 and 0.7080, respectively. The major conclusions of this study were as follows. First, applying the technical efficiency analysis, DMU2, DMU3, DMU8, DMU9, DMU11, DMU13, DMU14 were shown above average. It seems to have a regard for political elements in accordance with the regional social and economic differences. Second, as a result of scale efficiency analysis, the inefficient community welfare centers for people with disabilities such as DMU1, DMU5, DMU12, DMU16 are required to improve the number of employees, revenue, facility area. Finally, this study is expected to be an effectiveness analysis and performance evaluation for the rehabilitation services.

• Strategy21
• /
• s.41
• /
• pp.261-293
• /
• 2017

Nuclear power is a way of attaining an enormous amount of energy with relatively small amount of resources and after it has been introduced to the submarine since 1954, there are approximately 150 of nuclear powered submarine currently on a mission around the world. This is due to the maneuverability, mountability and covertness of nuclear submarines. However, there are other tasks, not only the high level of nuclear technology that are needed to be dealt with in order to construct nuclear powered submarine. The biggest task of all is to secure the enriched uranium. Accordingly, this research is about the way of enriching and securing the nuclear fuel that are used in the nuclear submarine with the characteristics, merits and demerits of the nuclear submarine. Due to the fact that the pressurized water reactor in South Korea is the reactor that was originally built for the development of nuclear powered submarine, many parts is designed to be suitable for the submarine propulsion. However, in order to apply this to submarine it is needed to consider additional requests such as the position of reactor, accident-coping system, radioactive covering, reactor output adjustment and ship's pitch and roll in order to apply this to submarine. Nuclear submarines have much higher speed based on the powerful propulsion in comparison with diesel-electric submarine and also have bigger loading area. Besides, there is no need to snorkel and they also have advantages in covertness with the multi-noise proof system. The nuclear technology in South Korea has seen the dramatic development since 1962 and in 1998 reached to the level that we have succeeded in the localization of nuclear plant and exported the world-class one-piece small-sized reactor (SMART) to UAE. To operate these reactors, we import the whole quantity of low-enriched uranium and having our own uranium enrich facility is not probable because of the budget and international regulations. With the ROK/US nuclear agreement revised on 2015 November, the enrichment of uranium that are available without special permission has changed up to 20%. According to the assumption that we use the 20% enrichment of Uranium on U.S. virginia class submarine, it is necessary to change the fuel after 11 years and it will cause additional cost of 1 billion dollars. But the replace period by the uranium's enrichment rate is not fixed so that it is possible to change according to the design of reactor. Therefore, I would like to make a suggestion on two types of design concepts of nuclear submarine that can be operated for 30 years without nuclear fuel change by using the 20% enriched uranium from ONNp.First of all, it is possible by increasing the size of reactor by 3 times and it results in the 1,000t increase of the weight. And secondly, it is by designing the one piece reactor to insert devices such as steam turbine, condenser into the inside of nuclear core like the Rubis class submarines of France.

• Spatial Information Research
• /
• v.20 no.6
• /
• pp.109-118
• /
• 2012

Recent increasement of metropolitan infrastructure due to rapid expansion and development of urban areas which caused complexity and diversification of management system demands higher cost and effort to manage and maintain the facilities. The reason why it requires continuous and systematic management by national government is that the infrastructure facilities takes important role as it is directly related to public's living. Thus this study suggests an efficient management plan for increasement of work efficiency, cost reduction, and time saving by introducing 3D geospatial information system for water distribution reservoirs which is managed by the Office of Waterworks Seoul Metropolitan Government. This study evaluates and quantifies the range of work improvement using the 3D GIS technology through carrying out a survey targeting people in charge of the Office of Waterworks Seoul Metropolitan Government and other 8 offices. From the result of the research, applying the 3D-GIS improves by 90.32%, 93.55%, and 91.61% in the area of work efficiency, cost reduction, and time saving respectively. Consequently, using 3D GIS in future management of infrastructure could be used as a way of producing base data which supports administrative decision making through statistical and case analysis based on continuous data management. Also it would contribute to improving work efficiency by improving management system through preventing data omission.

• Journal of Mushroom
• /
• v.13 no.4
• /
• pp.288-293
• /
• 2015

In the structural investigation of cultivation facilities, the proportion of farmers to grown with double or triple structure were investigated 96%. It has been shown to grow with a stable cultivation facilities structure against environmental changes. The results of the analysis of the changes in the cultivation environment of Yeoju area in July-august, temperature and humidity of the external instrument shelter was $20.2{\sim}29.9^{\circ}C$ and 66.2~99.9% respectively. In the greenhouse 2 model capable of temperature environment regulation in the cultivation facility, temperature and humidity were investigated $19.3{\sim}25.7^{\circ}C$ and 81.6~99.9% respectively. Result of the survey of fruiting body characteristics and yields in the greenhous 2, pileus diameter and stipe length were investigated 66.2 and 54.1 mm, yield of mushroom and individual weight were 312 g and 26.6 g. High-temperature environment regulation shows the improvement of the quality and productivity of the mushroom. Power consumption of the air conditioning has been investigated using 56kwh/day, electricity costs were calculated 2195 won/day.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.3
• /
• pp.401-412
• /
• 2020

This study analyzed the causes of warehouse fires using a creative problem-solving technique called TRIZ. It identified preventive measures by applying 4M. The results are as follows. First, this study examined the inconsistency among the causes of warehouse fires using TRIZ. Second, it analyzed human factors and fire prevention measures in warehouses such as safety standards for managers, and methods for the promotion of safety consciousness among workers, and for the reinforcement of construction technology for sandwich panel workers. Third, it identified the mechanical and facility factors and fire prevention measures in warehouses such as safety facilities, the expanded installation of safety devices, the adoption and development of fire suppression equipment, and the deployment of methods to improve the fire resistance of sandwich panels. Fourth, it presented working and environmental factors and fire prevention measures in warehouses such as the tightening of safety precautions and the supervision of working methods, and setting fire partitions both in loading places and based on performance-based design. Finally, it proposed managerial factors and fire prevention measures in warehouses such as specific targeting for firefighting with low fire hazards, reviewing the material quality regulations of non-combustible or higher for sandwich panels in the specific target of firefighting that cannot apply fire safety standards, installing sprinklers in cold storage, and mandating the installation of automated facilities with retroactive application regardless of the floor area in the warehouse with a sandwich panel structure.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.33 no.4
• /
• pp.361-367
• /
• 2013

Many of the nuclear power plant pipe is used in high temperature and high pressure environment. Wall thinning frequently caused by the corrosion. These wall thinning in pipe is expected gradually increase as nuclear power become superannuated. Therefore there is need to evaluate wall thinning in pipe and corrosion defect by non-destructive method to prevent the accident of the nuclear power facility due to pipe corrosion. Especially for real-time assessment of the wall thinning that occurs in nuclear power plant pipe, the laser ultrasonic technology can be measured even in hard-to-reach areas, beyond the limits of earlier existing contact methods. In this study, the optical method using laser was applied for non-destructive and non-contact evaluation. Ultrasonic signals was acquired through generating ultrasonic by pulse laser and using laser interferometer. First the ultrasonic signal was detected in no wall thinning in pipe, then a longitudinal wave velocity was measured inside of pipe. Artificial wall thinning specimen compared to 20, 30, 40 and 50% of thickness of the pipe was produced and the longitudinal wave velocity was measured. It was possible to evaluate quantitatively the wall thinning area(internal defect depth) cause it was able to calculate the thickness of each specimen using measured longitudinal wave velocity.

• Korean Journal of Childcare and Education
• /
• v.8 no.4
• /
• pp.185-206
• /
• 2012

The purpose of this study was to investigate the general tendency of styles for handl ing conflict and organizational effectiveness perceived by head teachers in child-care centers, and the relationship between head teacher's styles for handling conflict and organizational effectiveness. A total of 194 child-care head teachers who work in the Busan and Gyeongnam area responded to the questionnaire. The main results of the study were as follows; First, among the styles for handling conflict, the head teacher s used the most obliging type toward their principal, and also used the most integrati ng type toward colleague teachers. The head teachers perceived moderate or higher level of organizational effectiveness in child-care centers, and there were partial diffe rences in styles for handling conflict and organizational effectiveness depending on ag e, academic achievement, career of head teachers and facility type. Finally, it was fou nd that organizational effectiveness of child-care center were positively correlated wit h integrating type, dominating type and compromising type among all styles for hand ling conflict which head teachers adopted, but was negatively correlated with avoidin g type. Particularly, it was found that the head teacher's styles for handling conflict having most significant effects on organizational effectiveness were avoiding type to ward their principal and integrating type toward colleague teachers.