• The KSFM Journal of Fluid Machinery
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• v.18 no.2
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• pp.37-42
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• 2015

In the purpose of this study, we investigate the characteristics of the pilot-scale wastewater treatment system applied to BAF, MBR and IPNR as examining the removal efficiency of organic pollutants and operating factors in small decentralized wastewater treatment systems, and operating factors. For long-term operation period of more than nine months, pilot-scale plant operating results appeared very stable. This results were the removal efficiency of BOD was 80.3% above and removal efficiency of COD with an average of about 91.0%, satisfied the final effluent water quality standards. TN in the final effluents was the average concentration of 7.9 mg/L, was satisfactory water quality standards 10 mg/L of TN.

• Advances in Energy Research
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• v.5 no.3
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• pp.207-217
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• 2017

Energy consumption in agriculture is responsible for greenhouse gas emission but it can be reduced after efficient utilization of energy inputs. Therefore, the present study aims for the estimation of energy efficiency and extent of greenhouse gas reduction after benchmarking of inefficient farms in off-season tomato in Punjab province of Pakistan. Primary data were collected from 70 farmers with simple random sampling. By using data envelopment analysis, the average value of technical, pure technical and scale efficiency was 0.80, 0.92 and 0.87, respectively while increasing, constant and decreasing return to scale was observed in 33, 26 and 11 farmers, respectively. Total input energy was reduced by $12,688.91MJ\;ha^{-1}$ (13.89%) if inefficient farms used the energy inputs according to recommendations or benchmarking. A major portion of energy saving comes from fertilizers (68.79%) followed by diesel (15.70%), chemicals (5.91%), machinery (4.37%) and water (4.00%). Total greenhouse gases reduction was $499.17kg\;CO_2\;eq.ha^{-1}$ (14.57%) as a result of improvement in energy efficiency or benchmarking of inefficient farms. Agricultural extension staff should visit the vegetable farms on regular basis and give necessary information about efficient utilization of energy inputs. The government should create awareness about the optimum use of input through seminars and pamphlets.

• Korean Journal of Occupational Health Nursing
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• v.21 no.2
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• pp.116-124
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• 2012

Purpose: This study was conducted to examine the influencing factors of social support, self efficiency and depression among the hearing-impaired and physically disabled on their job stress. Methods: The data were collected from Jan.1 to Aug. 30, 2010 from 151 disabled workers. The instruments for this study were the Korean Occupational Stress Scale (KOSS), Social Support Scale, General Self-Efficacy Scale and Beck Depression Inventory-Korean Version (K-BDI). The data were analyzed using t-test, Pearson correlation coefficient and multiple regression with the SPSS/WIN 18.0. Results: The physically disabled show higher social support (t=0.284, p= .001) and self efficacy (t=0.165, p= .024) but lower in depression (t=0.789, p<.001) than the hearing-impaired. There are negative correlation between job stress and social support, job stress and self efficacy but a positive correlation between job stress and depression. These three factors explained 42.9% of the variance in job stress. Conclusion: Social support and self efficacy have positive impacts on job stress but depression has negative impact.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.579-582
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• 2007

In this paper, the inundation simulations were carried out by using GIS tools for the analysis of detention efficiency based on the results of runoff analysis according to location and scale of regional detention facilities. The inundation maps could be drawn by the inundation simulations, and the locations and magnitude of inundation areas could be estimated through the inundation maps. The inundation simulations with GIS tools are approved to be the one of the useful method in designing optimized location and scale of regional detention facilities.

• Journal of Integrative Natural Science
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• v.2 no.4
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• pp.237-242
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• 2009

As semitransparent dye-sensitized solar cells (DSSCs) have advanced to large-scale applications from lab-level research, the large-scale performance has attracted much attention. Modules of DSSCs have been investigated to optimize the efficiency as a $TiO_2$ systhesis temperature and a surface treatment of $TiCl_4$ aqueous solution. Essentially, these semitransparent modules have an extended structure with lab-scale works with the exception of the dimensions and methods for the series connection. The $5cm{\times}6.5cm$ modules have shown an efficiency of about 6% without a scattering layer. While the fill factors of modules depend on the width of each $TiO_2$ unit cell, they are much less dependent on the lengths of the unit cells.

• The Research Journal of the Costume Culture
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• v.6 no.2
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• pp.92-108
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• 1998

The purpose of this study was designed a) to examine the relative importance for college students' clothing disposal causes and their factor structure: b) to test the effects of gender, clothing satisfaction and family income on clothing disposal determinants; and c) to assess the relationship between clothing purchase determinants and overall clothing satisfaction and clothing disposal determinants. Data (n=660) were collected from college students in Cheju Do. The survey questionnaire composed of a revised Clothing Disposal Determinants Scale, Clothing Purchase Determinants Scale and background variables. First, the most important reasons for clothing disposal were to unfit with body change, get washed our and raise nap on clothe, wornout with long-term use, do not ware for new purchasing clothe, uneasy on wear. Second, factor analysis of the revised Clothing Disposal Determinants Scale revealed five factors; unfitness, fashion change, quality dissatisfaction, product efficiency decrement, and maintenance/inconvenience. Third, female students perceived significantly higher in fashion change and unfitness than male students. Forth, unfitness and product efficiency decrement were significantly discriminated between between clothing satisfaction groups, unfitness and fashion change variables were significantly discriminated between family income groups. fifth, impulsive purchase factor was the best predictor of composite clothing disposal measure, followed by individuality, clothing satisfaction, practicality. The best predictors of each disposal factors were individuality oriented purchasing criterion in unfitness factor. Fashion in fashion change, impulsive purchase in quality dissatisfaction and product efficiency decrement factors, and practicality in maintenance/inconvenience factor. As a whole, the most consistent predictor of clothing disposal determinants was impulsive purchase factor.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.169-174
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• 2006

This paper is related to a design of high pressure sub-scale combustor with regenerative reeling. As a previous step for the evaluation of thermal heat flux, a similar combustor with cooling water was manufactured. Design conditions with high combustion efficiency and cooling performance were verified through the hot firing tests of the water-cooled high pressure combustor. Finally the regeneratively cooled high pressure combustor has been designed based on these data. After manufacturing it, its practical utility will be tested and verified through hot firing tests.

• KIEAE Journal
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• v.15 no.5
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• pp.75-82
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• 2015

Purpose: The first grade of Korea's Building Energy Efficiency Rating System(BEERS) is required for new government office buildings as a mandatory measure to reduce greenhouse gas emission. However, there is no specific criteria about performance that which level should apply to energy-saving design element for obtaining Building Energy Efficiency Rating 1st grade. Therefore, Certification status should be analyzed firstly, about the office building which is certificated. Certification analysis for office buildings acquired certification therefore should be done first. Method: In this study, Certification status(Office buildings acquired Building Energy Efficiency Rating Certification)was analyzed by classified year, region, specific scale etc. And we analyzed statistically by eliciting an average value of each element influencing to the amount of energy. Result: Energy demands were gradually decreased due to revision of thermal insulation standards for enhanced u-value. Energy consumptions were different from the kind of equipment and yearly trends applied depending on the size of the building. Total primary energy consumptions were influenced by heat source types and the primary energy scale factors.

• Journal of Information Technology Services
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• v.16 no.4
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• pp.15-31
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• 2017

This study analyzes 45 Korea IT service companies from 2012 to 2016 using DEA analysis. Large enterprises, medium enterprises and small and medium enterprises (SMEs). CCR model and BCC model were used for efficiency analysis. Among the various analytical objects, the decision objects which yield the maximum output with minimum input are compared with other analysis objects. The relative inefficiency was measured through this, and Technical Efficiency (TE), Pure Technology Efficiency (PTE), Scale Efficiency (SE), scale profit, reference frequency were analyzed. Also, we analyzed the Technology Gap Ratio (TGR), which is the distance between production function and Meta-Frontier for each firm, using Meta-Frontier analysis. Finally, the Tobit model is used to analyze the sources of efficiency and inefficiency. The inputs are assets, capital, and employees, and the output factor is sales. The analysis shows that large firms are achieving technological achievements more efficiently than small and medium enterprises. As a result, medium-sized enterprises and SMEs can improve efficiency overall through efficient operation of workforce and appropriate combination of inputs such as assets and capital. Also, as a result of the influence factor analysis, it was found that the ratio of the managed asset ratio and the management cost ratio were significant factors influencing the efficiency of the IT service companies. This study suggests the efficiency analysis using DEA for many Korea IT service companies. Inefficient parts of each company are classified according to size and technology. Also, we identify the most efficient companies and analyze the causes of those companies whose profits are lower than their size.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.265-271
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• 2016

DEA is a typical method that allows measurements and evaluations of the efficiency. This study examined the management efficiency of bean farm households to suggest factors that influence the management efficiency. The results showed that a larger cultivation area has more positive effects on the scale efficiency of beans farm households. When summing up farmer's family labor, lease fee, hired labor cost, which are strongly related to the workforce, it reached up to 54.6%. This means that they all occupy more than half of the production cost and they show an increasing trend. Moreover, although the hired labor rate is higher, it has more positive influences on the gross efficiency, technical efficiency and scale efficiency. In addition, the results showed that environmentally-friendly agriculture decreases the efficiency.