• Korean journal of communication and information
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• v.29
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• pp.111-145
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• 2005

In this study, the problems In the current HDTV programming strategies were critically inquired into and reform measures were sought through in-depth interview with HDTV programming staff and program directors of the three major terrestrial broadcasting systems that are in their fourth year of HDTV broadcasting, and through analysis of the characteristics of HDTV programming. The analysis of this study showed that the time allocated to HDTV programs far exceeded the thirteen hours per week set by the Korean Broadcasting Commission. However, the percentage of HDTV programs broadcasted during the prime time was low, which as a result, limited the opportunity for the audiences to experience HDTV. furthermore, the low percentage of programs such as documentaries, sports, movies, etc. that are preferred by early adopters and through which the features of HDTV including high quality of picture, wide screen, etc. can be fully applied and shown did not appear to help in accelerating the popularization of HDTV In order to improve these problems, despite their having to bear the initial production costs, the broadcasting systems must come up with an aggressive strategies for the programming of documentaries, sports programs and dramas in order to strengthen the competitiveness in HDTV production and secure future adopters, and together with this, full support from the policy planning authorities and companies manufacturing electric home appliances, the other leaders in DTTB(Digital Terrestrial Television Broadcasting) transition, are necessary in order to promote the production of HD contents.

• Clean Technology
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• v.13 no.1 s.36
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• pp.1-15
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• 2007

Biological treatment is a relatively recent air pollution control technology in which off-gases containing biodegradable odors and volatile organic compounds(VOCs) are vented through microbes. It is a promising alternative to conventional air pollution control methods. Bioreactors for air pollution control have found most of their success in the treatment of dilute and high flow waste air streams containing VOCs and odor compounds. They offer several advantages over traditional technologies such as incineration or adsorption. These include lower treatment costs, absence of formation of secondary pollutants, no spent chemicals, low energy demand and low temperature treatment. The three most widely used technologies are described, namely biofiltration, biotrickling filtration, bioscrubbing. The most widely used bioreactor for air pollution control is biofilter, but it has several limitations. In the past years major progress has been accomplished in the development of vapor phase bioreaction systems, for solving problems of biofilter. Biotrickling filters are more complex than biofilters, but are usually more effective, especially for the treatment of compounds which are difficult to degrade or compounds that generate acidic by-products. This, paper reviews fundamental and theoretical/practical aspect of air pollution control in biofilter, biotrickling filter and bioscrubber, focusing more extensively on biotrickling filtration. Special emphasis is given to the operating parameters and the factors influencing performance for air pollution control, and cost estimation in biotreatment technologies.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.6
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• pp.397-405
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• 2012

In this study, performance evaluation of newly developed technology for the economical and safe removal of volatile organic compounds (VOCs) coming out from electronic devices washing operation and offensive odor induction materials was made. Metal oxidization catalyst has shown 50% of removal efficiency at the temperature of $220^{\circ}C$. Composite metal oxidization catalyst applied in this study has shown that the actual catalysis has started at the temperature of $100^{\circ}C$. Comprehensive analysis on the catalyst property using Mn-Cu metal oxidization catalyst in the pilot-scale unit was made and the removal efficiency was variable with temperature and space velocity. Full-scale unit developed based on the pilot-scale unit operation has shown 95% of removal efficiency at the temperature of $160^{\circ}C$. Optimum elimination effective rates for the space velocity was found to be $6,000hr^{-1}$. The most appropriate processing treatment range for the inflow concentration of VOCs was between 200 ppm to 4,000 ppm. Catalyst control temperature showed high destruction efficiency at $150{\sim}200^{\circ}C$ degrees Celsius in 90~99%. External heat source was not necessary due to the self-heat reaction incase of VOCs inflow concentration is more than 1,000 ppm. Equipment and fuel costs compared to the conventional RTO/RCO method can be reduced by 50% and 75% respectively. And it was checked when there was poisoning for sulfide and acid gas.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.133-138
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• 2020

In 2016, the two-spotted cricket was approved as a general food ingredient by the Korean Ministry of Food and Drug Safety. Additionally, the two-spotted crickets have high protein content (60%) and can be reared throughout the year even during the overwintering period. In this study, storage conditions were set in case cricket breeding was not possible due to problems such as breeding space and labor costs, and selection oviposition mats to determine high fecundity rates and low cannibalism rates for the eggs were investigated. The oviposition mat was mostly composed of soil (p < 0.05). Less than 62 crickets per 10 litters were found to be best suited for 1 day of spawning, based on the cannibalism rate of the eggs during the egg laying period. The results from the hatched eggs indicated that the hatching extended 12 to 14 days, and the best hatching rate was approximately 85% when stored at low temperatures(16℃) for 10 days. An efficient production proposed method that established the best oviposition mat and egg storage method for the cricket.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.5
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• pp.685-692
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• 2018

Busan city implemented 'taxi transfer discount system' since October 2017 in order to create for new demand taxis. However, due to the low transfer discount amount and limited payment method to prepaid cards, it is difficult to attain the aim. In this study, we investigated the usage status of taxi transfer discount system and the intention to use taxi transfer discount system according to the discount amount level. We established a model of intention to estimate demand of taxi transfer discount using ordinal logistic model. The results of analysis are as following. The critical reason for low usage was to limit taxi transfer discount payment methods to prepaid cards other than post-paid cards which is used for most transportation payment. It was found that the discount rate for taxi transfers was affected in order of payment method, the purpose of the travel, major transportation, frequency taxi use, age, transportation costs, and the discount of taxi transfers. Also, the taxi transfer discount could be expected to increase to 1,550 won based on the price elasticity of demand due to changes in taxi transfer discount rate.

• Management & Information Systems Review
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• v.39 no.3
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• pp.83-98
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• 2020

This study analyzes how investors' irrational behavior (or pessimistic sentiment) affects stock market returns and investors' market activity using mass media that delivered public information from January 1998 to December 2012 as a sample. According to pessimistic investor theory, investor pessimism leads to downward pressure on the price of equity capital, thereby making market sentiment pessimistic and lowering market yields. It also shows that investor pessimism increases transaction costs in the market, which in turn dampens investors' trading activities. In other words, pessimistic reporting on public information disseminated by mass media induces investors to act irrationally, eventually having a direct impact on the stock market. This study conducted an empirical analysis of the existing theoretical and empirical studies using domestic mass media as a sample. First, the study revealed a negative correlation between pessimistic reporting and returns as well as excess returns, while it did not show statistically significant results. Second, evidence has been suggested that pessimistic sentiment in the stock market has a negative impact on future pessimistic reporting by mass media. Third, the analysis of the impact of pessimistic reporting on investors' market activity using proxy variables for various market activities found that pessimism dampens market activity, while it did not show statistically significant results. It is assumed that low statistical significance is due to the fact that sample collection was carried out on a monthly basis. While the results of the study have low statistical significance, statistical signs support predictions of the theory.

• The Journal of the Korea Contents Association
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• v.17 no.9
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• pp.449-465
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• 2017

Small and medium-sized company workers are ill-prepared for retirement due to low wages and poor working conditions, as result, are likely to get into poverty in retirement. The purpose of this study is to conduct a case study on the current status of financial and non-financial retirement preparation of the small and medium-sized company workers. The main findings are as follows. First, the small and medium-sized company workers show the anxiety about retirement. Many pre-retirees worry that their retirement savings may not generate enough income in retirement, and the level of benefits paid in public pension is inadequate. Second, they are preparing for retirement in the areas of finance, health, working after retirement and social activity. Third, they are realistic and practical in retirement decisions makings. they are considering household budget downsizing, cutting education costs, the low-waged job choice and cash flow preference in retirement. The safety and reality in preparation for retirement are top considerations. In conclusion, this case study shows that pre-retirees of small and medium-sized companies are seeking diverse retirement solutions. We need to design integrated and practical retirement planning programs to support their specific retirement needs.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.302-312
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• 2019

The purpose of this study was to analyzed the effects of educational recognition sub-factors (necessity, utility, value, cost, adequacy) on the field usability and satisfaction and the correlation between each factor for 220 applicants who have taken the national technical certificate of cosmetologist (make-up). In the practical courses of makeup certificate, the most-used course was selected as beauty makeup. It found for improvement need cause there was a high necessity and there was a low recognition of the cost, the number of annual written and practical test in the recognition of certification education. In field usability 'Beauty make-up utilization' showed high recognition, and it showed high satisfaction for acquisition of certificate satisfaction, 'The salary' showed low recognition. The necessity, cost, adequacy among educational recognition sub-factor of the national technical certificate had a significant positive effect on the field usability and satisfaction, and showed the most effect as adequacy on the field usability and the cost on the satisfaction. Therefore, efforts are needed to reduce acquisition costs of certificate and improve highly available theories and technique for segmentation and specialization of make-up certificate.

• Korean Journal of Labor Studies
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• v.24 no.3
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• pp.35-71
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• 2018

The purpose of this study is to examine which job-related factors are associated with presenteeism, which is defined as attending work while ill. Although presenteeism is a relatively new concept in academic research, it should be regarded as an important social issue in that presenteeism threatens employees' job prospects and quality of life as well as it causes loss of work productivity. I analyzed a cross-sectional survey of 24,571 wage workers over 15 from the fourth wave of the Korean Working Conditions Survey in 2014. Five logistic regression models were analyzed on experience of presenteeism, and work hours and private life, occupational environment, job insecurity, rewards and welfare were assessed as key predictors of presenteeism. I found that 1) work hours with bad fit with private life, 2) high level of work time-pressure, and low job satisfaction 3) job insecurity, and 4) low benefits are associated with experience of presenteeism. The findings are fairly consistent with the theory of job-person mismatch, which explains that workers tend to preserve their personal resources by going to work while ill (presenteeism) when job demands or work conditions do not match with their level of personal expectation and, thus, workers are afraid of loss of personal resources. Presenteeism influences worker's long-term health and quality of life negatively as well as causes serious social costs. Therefore, we need organizational efforts to prevent the negative effects of presenteeism on society as well as workers.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.42-54
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• 2019

Crop models depend on a large number of input parameters including the cultivar parameters that represent the genetic characteristics of a given cultivar. The cultivar parameters have been estimated using high quality data for crop growth, which require considerable costs and efforts. The objective of this study was to examine the feasibility of using low quality data for the parameter estimation. In the present study, the cultivar parameters for cv. Shindongjin were estimated using the data obtained from the report of new cultivars development and research from 2005 to 2016. The root mean square errors (RMSE) of the heading dates were less than 3 days when the parameters associated with phenology were estimated. In contrast, the coefficient of determination for yield tended to be less than 0.1. The large errors incurred by the fact that no growth data collected over a season was used for parameter estimation. This suggests that detailed observation data needs to be prepared for parameter calibration, which would be aided by remote sensing approaches. The occurrence of natural disasters during a growing season has to be considered because crop models cannot take into account the effects of those events. Still, our results provide a reasonable range for the parameters, which could be used to set the boundary of a given parameter for cultivars similar to cv. Shindongjin in further studies.