• Aerospace Engineering and Technology
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• v.9 no.2
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• pp.204-209
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• 2010

The current status of the development of pyrostarters, which play a role as a turbo pump starter in liquid propellant propulsion systems by supplying pressurized gas to power turbines for engine start, has been introduced. Firstly, the development history is briefly summarized, and secondly the current technical status in core parts for the development of pryrostarters such as solid propellants, internal ballistics, rupture discs, and igniters are presented. The current technical achievements could make it feasible to fulfill the development requirements for pyrostarters.

• Korean Journal of Plant Resources
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• v.24 no.6
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• pp.733-740
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• 2011

For the current study, 2,000 questionnaire sheets were printed and distributed while at the same time postal questionnaires were also conducted. The questionnaire survey was conducted July 25 through September 25, 2008, whereby 206 copies of desirable responses were secured. Analysis of the survey made it possible to grasp the overall current status and prospects of the mountain-grown ginseng business, and the level of technology required for cultivating mountaingrown ginsengs. It was learned that, with no legal and institutional arrangements now in force, no precise facts and figures concerning the total area cultivated and the quantity produced are currently available, and that the products are being marketed under the table. Under such circumstances, it is high time for the mountain-grown ginseng cultivation business to contribute to the promotion of incomes of the farming households and the generation of national wealth by developing the business into a systematic industry. This study conducted a survey on the current status of mountain-grown ginseng producers and of their production, thereby contributing to the introduction of policies for mountain-grown ginsengs.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1127-1130
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• 2008

Integral imaging is a three-dimensional display technique which has 100 years of history. The method is characterized by offering full parallax, almost-continuous viewpoints and easiness of moving picture display. In this paper, the history of the method is briefly explained and overview of its current status is provided.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.229-230
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• 2000

The current status of OLEDs technology is reviewed. Comparison has been made between small molecule based OLEDs and polymer LEDs. In addition, advantages of OLEDs technology and technical issues for commercialization are addressed. Details of these issues will be discussed at the meeting.

• Journal of Ecology and Environment
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• v.36 no.1
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• pp.113-116
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• 2013

The current status of Korean jewel beetle, Chrysochroa coreana is reported from the data collected in the five-year field survey (2008-2012). Despite the previous assumption of its endangered status, the beetle was recently found in the southwestern part of Korea frequently. However the local population was suffering from the inadequate management of its host plants, Celtis sinensis Persson. This study reports the restoration possibility of the beetle by the adequate management of its host plants.

• Architectural research
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• v.18 no.4
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• pp.185-190
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• 2016

This study aimed to investigate whether protestant religious facilities are maintained appropriately for people and regular inspections are conducted. As a study method, survey and site investigation were conducted. The survey questionnaire aimed to know the perception of users or responsible persons about safety management and current status of safety management systems while the site investigation aimed to inspect structural conditions by a visual inspection such as proper installation of fire protection equipment and whether regular inspection were conducted. It was found, through the inspection of the current safety management status, that the safety management related persons did not know which parts and how much they manage incorrectly, and did not know the follow-up actions in case of accidents. Therefore, it is essentially required to assign a proper person to the facilities for safety management and to have safety consciousness education. Furthermore, although more than 80% of the surveyed subjects responded that they were familiar with the way to use safety management related facilities and overall instructions, the respondent were concerned about the correspondent training for emergent circumstances.

• The Journal of Fisheries Business Administration
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• v.46 no.2
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• pp.43-57
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• 2015

The study aims to identify the current status of aquaculture information in Korea and suggests policy directions for its integrated management. Firstly, the study focuses on the identification of the current status of aquaculture information by reviewing how aquaculture information is managed. Secondly, this study identifies problems such as lacks in necessary aquaculture information, inefficiency caused by dispersion and overlapping of information, absence of integrated management system and insufficient sharing of information. After identifying the current status of aquaculture information and its problems, the study suggests three basic directions to systematically integrate and manage the information such as establishment of infrastructure for promoting the integrated management of aquaculture information, generation and systematic management of useful aquaculture information and enhancement of user convenience. Finally, the study suggests detailed strategies such as establishment of a foundation to facilitate integrated management of aquaculture information, organization of organic network, sharing of more information, creation of necessary information through demand survey, creation of systematic management system, provision of a customized total service, and increase in education and PR activities on information use.

• Journal of Korean society of Dental Hygiene
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• v.10 no.5
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• pp.917-924
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• 2010

Objectives : The objective of this research was to investigate the smoking state of students in Y university, located in Youngdong-gun, Choungbuk. Methods : This research was conducted toward 311 number of students in the university. The questionnaire basically consists of the status of smoking, the behavior of smoker and non-smoker. Results : 58.2% of the male respondents were current smoker, but 72.4% of the females were non-smoker. 58.2% of the current smokers were 22 to 25 aged group. The highest rate of time to begin with smoking was in 15 to 18 years old and the most of people consumed 11 to 20 pieces of cigarettes per day. 48.9% of the students have an experience to keep no smoking more than one month. There were reverse correlation(r=-.335) between the status of smoking and sex, and positive correlation(r=.264) between the status of smoking and an age. Of the people experiencing non-smoking, 55.3% were smoking 'everyday' and 44.7% were 'sometimes'. The biggest part of the reason why stopped smoking was for 'the advices of other people'(25.5%), and 'Harm to health' and 'Social atmosphere of non-smoking'(21.3%) were following. Conclusions : In the university students, current smokers among male students were still high smoking rate. Therefore Dental Hygiene students in the same University have to provide the quit smoking education and oral health care methods for current smokers.

• International Journal of Human Ecology
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• v.13 no.1
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• pp.129-145
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• 2012

The purpose of this study was to investigate housing cost burden of U.S. households according to current and previous tenure types and explore influences on their housing affordability. The public-use microdata of the 2009 American Housing Survey was analyzed in the following two stages: In the first stage, households were classified into eight groups by combining their current and previous tenure types, year moved into current housing units and mortgage status of current owners and their characteristics were compared. In the second stage, the factors that influenced the housing cost burden by each combined tenure group were explored using multiple regression analyses. The findings are as follows: (1) The mortgage status was more influential than the previous housing experiences of owner households to distinguish one owner household from another. (2) Renter households who had been owners of previous housing units showed significantly different characteristics compared to continuing and new renter households in terms of income, educational attainment, and householder's marital status as well as housing costs and housing cost burdens. (3) To see the multiple regression analysis results, households with different current and previous tenure types were found to have different factors that influenced the housing cost burdens. In addition, household characteristics were found to have significant influences on housing cost burdens as strong as cost-related variables such as annual mortgage payments and rent per square footage.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.5
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• pp.457-462
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• 2017

This paper proposes a digital power control of the LLC resonant half-bridge inverter for high power microwave oven application. Conventional half-bridge inverter for driving a microwave oven uses a hardware-based power control method which varies the frequency according to the AC source voltage. In this case, it is difficult to control the output power according to the variation of the load status of magnetron. The proposed power control consists of an instantaneous current generator and a current controller. Instantaneous current generator makes an instantaneous current reference from power command using input voltage information. Current controller controls input current which has an information of status of magnetron. The proposed power control does not require any compensation algorithm for the change of the load status of the magnetron and change of input voltage. The validity of the proposed method for the control of the change of input voltage and frequency is verified by both simulation and experiment.