• Journal of Navigation and Port Research
• /
• v.39 no.6
• /
• pp.457-463
• /
• 2015

A gas turbine engine plays an important role as a prime mover that is used in the marine transportation field as well as the space/aviation and power plant fields. However, it has a complicated structure and there is a time delay element in the combustion process. Therefore, an elaborate mathematical model needs to be developed to control a gas turbine engine. In this study, a modeling technique for a gas generator, a PLA actuator, and a metering valve, which are major components of a gas turbine engine, is explained. In addition, sub-models are obtained at several operating points in a steady state based on the trial running data of a gas turbine engine, and a method for controlling the engine speed is proposed by designing an NPID controller for each sub-model. The proposed NPID controller uses three kinds of gains that are implemented with a nonlinear function. The parameters of the NPID controller are tuned using real-coded genetic algorithms in terms of minimizing the objective function. The validity of the proposed method is examined by applying to a gas turbine engine and by conducting a simulation.

• Journal of the Korean Institute of Gas
• /
• v.18 no.5
• /
• pp.47-51
• /
• 2014

This paper is to analyze and study the fire examples in respect of intake and exhaust, alternator tuning and inflow of inflammables on exhaust part in a car. In the first example, the driver diverted the intake and exhaust system for tuning of a car. Stopping a car to rest for moment, the flammable styrofoam scrap go into exhaust pipe that installed with exhaust manifold newly. It certified the fact that catched fire gradually, furthermore enlarged the fire by leaking fuel. In the second example, the driver enlarged the generator performance to divert the audio system in side room., it knew the fact that the electric wiring connected with generator gave the cause of outbreak a fire by overheating. In the third example, the serviceman replaced the engine oil using funnel-shaped, he put the a bottle of plastic pat onto engine cover carelessly. Consequentially, it found the fire occurrence in the engine room. Therefore, the driver never divert the intake and exhaust and generator construction of a car abnormally. Also, repairing and inspecting a car, the serviceman have a care to not occur the fire by inflammables.

• Korean Security Journal
• /
• no.16
• /
• pp.161-187
• /
• 2008

The purpose of this study is to suggest a development method of current Korean security system by analyzing the problems shown in the performance of security work in relation to the terrorism, which is enlarging in the word, from various aspects. In order to perform the study, the researcher considered the basic theory concerned to current Korean law concerned to security, principle and methodology of security, terror and new terrorism. The researcher performed the study by selecting qualitative case study focused on Park Geun-Hye case. Through the study, the methods to develop Korean security system are as follows. First, from the legal aspect, it is necessary to establish the law concerned to terrorism prevention and important person security. Moreover, it is necessary to search for the development of private security by revising Security Industry Act, which is a legal ground of private security. Second, it is necessary to improve and reinforce education & training program, which is not still divided in detail from the aspect of private security cultivation. Moreover, it is necessary to activate personal protection work and enlarge market through Security Industry Act and make an effort to change social recognition over security, which is devaluated in the society. From the viewpoint, national license about private security shall be adopted. The department of president security, which is a representative of official security, shall transfer the advanced technology to private security organization. Third, from the aspect of operation, the operation of security based on SCE principle, human shield principle, the nearest person's protection principle, body extension principle, linear protection principle and evacuation priority principle is required. Therefore, the priority shall be given to preventive security and thorough security plan shall be made for the operation.

• Journal of Preventive Medicine and Public Health
• /
• v.29 no.4 s.55
• /
• pp.863-875
• /
• 1996

In order to prepare the fundamental data for the health promotion by assessing the exposure level of styrene, the author determined the concentration of mandelic acid and phenylglyoxylic acid in urine of 42 workers who were exposed to styrene by high performance liquid chromatography and surveyed 16 symptoms, by questionnaire and also tested neurobehavioral test(digit symbol, benton visual retention) in 2 FRP plants of Kyung Nam area from July to September, 1995. Control was sampled by age sex matching method. The concentration of styrene in air was determined by gas chromatography. The results were as follows; 1. Geometric mean concentration of styrene in air was 17.4ppm, geometric mean concentration of mandelic acid(MA) in urine were 404.3mg/g creatinine for exposure group, 46.4mg/g creatinine for control group, geometric mean concentration of phenylglyoxylic acid(PGA) in urine were 57.5mg/g creatinine for exposure group, 9.5mg/g creatinine for control group. Mean concentration of MA and PGA showed statistically significant difference between exposure group and control group(p<0.01). 2. Number of symptom were 2.9 for exposure group, 3.3 for control group, number of digit symbol were 24.1 for exposure group, 32.5 for control group, number of Benton visual retention test were 6.1 for exposure group, 6.0 for control group, respectively. As result of adjusting the education year, number of Benton visual retention test showed statistically significant difference between exposure group and control group(p<0.05). 3. Excellent correlation were observed between environmental styrene exposure and urinary MA(r=0.80), PGA(r=0.73), and MA+PGA(r=0.81).

• Journal of Gifted/Talented Education
• /
• v.10 no.2
• /
• pp.47-69
• /
• 2000

One of the most controversial issues in contemporary research of creativity, whether a person"s creativity is domain-specific or domain-general, was investigated with 109 second grade children in the present study. The purposes of this study sere to empirically examine (1) the relationships among children's creative performances measured by three product-based assessments (story-telling, collage-making, and math word problems) in three domains, and (2) the relationships between children's general creative thinking sills, measured by two divergent thinking tests, and children's creative performances. The findings of this study support the position that creative ability in young children is rather (but not absolutely0 domain-specific. Children exhibited a range of creative ability across different domains rather than a uniform creative ability in diverse domains, indicating there is considerable intra-individual variation in creative ability by domain. Divergent thinking measures did not have great power in predicting creative performance in at least two of three, if not all, domains assessed in the study. It is implied from the study that it is not possible to reliably predict a child"s creative ability in one domain based on his/her creative ability in other domains or his/her overall divergent thinking ability. Implication of the study in connection with educational practices for gifted children is discussed.

• Journal of Nutrition and Health
• /
• v.44 no.1
• /
• pp.74-81
• /
• 2011

The purpose of this study was to investigate the sanitation management of school foodstuffs and the sanitation knowledge of delivery company workers. A questionnaire that identified employee's food safety sanitation management, knowledge, and practices was developed based on a review of the literature. The subjects consisted of 201 delivery company workers from 38 delivery companies in the Daegu and Gyeongbuk area. The workers were 30-39 years of age (41.3%) with 1-3 years of working experience (30.8%). Approximately 62% of the respondents were educated and had 1-2 years of food safety experience, 52.7% of the respondents delivered foodstuffs to two schools in the morning. The total score for delivery company worker sanitation knowledge was 3.75/7.00, which was low. The total mean sanitary performance score for factory workers was 4.58/5.00. They indicated that the most difficult part of the operation is delivering on time. Temperature management was another difficulty. In order to secure the best quality of school food to be supplied safely, the thorough sanitation education must be conducted to the school dieticians and delivery company managers.

• Journal of Distribution Science
• /
• v.7 no.4
• /
• pp.27-36
• /
• 2009

In the performance of this research we aimed at surveying·studying the trouble factors, problems and improvement plans to extend agricultural products and agro-food and providing basic data for the globalization of Korean agricultural products and agricultural foods in future. All the respondents highly recognized, in general, the problems in exporting agricultural products and agro-food, and it was surveyed that the biggest reason lay in the insufficiency of the scout for new buyers and the lack in opening overseas market and marketing specialists. As for the problems of the supporting system of the export of agricultural products, it was pointed out that the level of recognition was fairly high, but the procedures were difficult, and they indicated the problems of non-benefits in spite of the recognition of the selection. For the purpose, it could be known that it required the publicity and education as to export supporting system, and also required the extension of export supporting system and the improvement of the system. Finally, in relation with the export promotion plan, the factors blocking the export promotion of agricultural products marked the highest in the weak management size and production foundation and the lack in export mind and special workforce. Therefore, considering that most of exporters of agricultural products are small/medium sized businesses, we foresaw that we lack in the opening of overseas market and the capacity of marketing activities, and analyzed that it was necessary to open an overseas market in the dimension of the government and cooperate with the marketing to solve the problems.

• Korean Journal of Social Welfare Studies
• /
• v.48 no.1
• /
• pp.91-111
• /
• 2017

Purposes of this study, summoning thoughts and activities of Toynbee Hall of the UK and Hull House of the US held in between the end of 19C and the early 20C, are two folded: first, it is to examine the momentum and aims for which 'social' work was progressively established at that time; second, it is to look for implications for today's social work practice through understanding their characteristic activities and the context in which 'social' work was devised as an alternative in the two nations. The study method mainly relies on literature review, but further goes on to analyze the spirit of the age when settlement house was constructed as a welfare space and activities, leadership demonstrated in there, and to draw meanings for today, in terms of three dimensions: aim and location, professionality and education, and social action. Some of useful findings are: first, the COS and settlement house need to be considered in a continuum of socially responsive remedies against poverty and social work practice was developed in the process of 'suggestion-performance-critique-alternative suggestion-emergence of social work', rather than contrasting the two as opposite roots of social work practice. Second, settlement house was a socially constructed welfare space that contained intersectional dynamics of class, gender, personal vs. social, private vs. public, surrounding poverty issue. Third, besides differences between the two settlements, both purported for public goods and well-being and tried to realize the 'social' in that society. Lastly, this study explored historical meanings of settlement house as the welfare space with critical questions and discussed implications for social work practice today.

• Review of Culture and Economy
• /
• v.21 no.3
• /
• pp.59-88
• /
• 2018

This study examines demand of the Korean TV VOD using monthly aggregate data and time series analysis models. In particular, the impact of box office attendance, number of IPTV subscribers, income and price of substitutes on TV VOD market is analyzed. Data on TV VOD download during the period 2013 January to 2018 June are used for the empirical analysis. TV VOD demand shows lower level of seasonality than box office attendance and the share of monthly top1 movie in TV VOD platform is also lower than that of box office attendance. The relationship between a movie's holdback and box office performance does not seem consistent. The empirical result of ARDL model reveals that in the short-run box office attendance, number of IPTV subscribers and price of substitutes have significant impact on TV VOD demand. The result on the long-term relation shows that income is the only determinant of TV VOD demand. The impact of box office attendance on TV VOD is not shown to be robust both for the short-term and long-term.

• Review of Culture and Economy
• /
• v.17 no.2
• /
• pp.3-28
• /
• 2014

The characteristics of performing arts differ from those of utilitarian goods in terms of economics. Factors other than price need to be considered to understand the demand for performing arts. Audience surveys as well as econometric demand studies have confirmed that socio-economic factors such as age, income, employment, and education are major determinants of the demand for performing arts. This study focused on the attributes of concerts rather than consumer characteristics to determine the concerts audiences select in terms of transaction cost. Genre, price, internet search trends, and the purpose of performance as well as price are tested as determinants of demand by using the data set for a major concert hall in Seoul. Genre and the specific purpose of concerts influence the demand for concerts. Internet search trends of the performer are used as indicators of popularity and information exposure, which are positively correlated with demand. This result supports the hypothesis that larger audiences would attend concerts that require lower information search costs. To note, price has a positive effect on demand in the higher price range, which means that concerts at higher prices attract larger audiences, whereas normal goods have a negative slope in the demand curve. This result can be explained by the hypothesis that consumers use price as an indicator of the quality expected of a concert. Transaction cost for selecting classical concerts thus forms an inverse-U shape curve against ticket price. These results provide some explanation of why audiences of classical music choose to attend concerts at high ticket prices while offering evidence in favor of the hypothesis that performing arts are selected in a social context.