• International Journal of Aerospace System Engineering
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• v.2 no.2
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• pp.29-33
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• 2015

The multidisciplinary design optimization (MDO) of a launch vehicle (LV) with a hybrid rocket engine (HRE) was carried out to investigate the ability of an HRE for a single-stage LV. The non-dominated sorting genetic algorithm-II (NSGA-II) was employed to solve two design problems. The design problems were formulated as two-objective cases involving maximization of the downrange distance over the target flight altitude and minimization of the gross weight, for two target altitudes: 50.0 km and 100.0 km. Each objective function was empirically estimated. Several non-dominated solutions were obtained using the NSGA-II for each design problem, and in each case, a trade-off was observed between the two objective functions. The results for the two design problem indicate that economical performance of the LV is limited with the HRE in terms of the maximum downrange distances achievable. The LV geometries determined from the non-dominated solutions were examined.

• The Journal of Korean Association of Computer Education
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• v.16 no.3
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• pp.89-98
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• 2013

In order to effectively manage after-school works from 2011, NEIS after-school system has been developed and operated. As NEIS after-school system that has been currently operating will need to analyze the effectiveness, it makes the use of this system activate. After-school elementary school teacher 273 people survey of 11 school district of the Seoul Metropolitan Office of Education was commissioned. 116 teachers participated in the survey. NEIS after-school system showed a reduction in task processing time (M = 3.92) were higher than that of most complaints about paperwork (M = 3.82), work efficiency (M = 3.81), the accuracy of your work (M = 3.76) in the order of many complaints were.

• International Journal of Human Ecology
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• v.3 no.1
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• pp.127-136
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• 2002

According to the Labor Standard Law in Japan which was enacted after World War II in 1947, all work hours for adult men, women, and youth were set at a maximum of eight hours per day and forty-eight hours per week. In other words, a six-day work week, with only one-day off, was set. Now we are in the full five-day and two-day off school system. The five-day school week influences on our home life. Students are highly enthused by the new system, in looking forward to their personal time they now have to play with friends, to relax, or just watch TV. To implement this new five-day school system positively and effectively, we should see the point at issue related to the two-day off system from a different angle, which suggests that we should see far ahead into the future.

• Journal of Power Electronics
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• v.19 no.1
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• pp.316-331
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• 2019

A practical application of a supercapacitor energy storage system in a polarization instrument is proposed on the basis of the energy storage requirements of an induced polarization (IP) transmitter for geophysical exploration. We focused on the energy storage system of a supercapacitor, the topology of the power converter, and the system control strategy as key technologies, and we performed theoretical research and experimental tests on the system and developed an experimental platform. The experiments validated the theoretical research on the key technologies of the supercapacitor energy storage system and demonstrated the effectiveness of the innovation. Results showed that the storage system is efficient and satisfies the energy storage needs of the IP transmitter.

• Journal of Integrative Natural Science
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• v.12 no.3
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• pp.74-77
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• 2019

The purpose of this study is to explore the effects of Chamaecyparis obtusa essential oil on the activity of autonomic nervous system. Heart rate variability (HRV), as an indicator of autonomic nervous system activity and blood pressure were measured before and after inhalation of Chamaecyparis obtusa essential oil. The systolic blood pressure was decreased by inhalation of Chamaecyparis obtusa essential oil (p<0.05). The diastolic blood pressure was not changed significantly by Chamaecyparis obtusa. High frequency (HF) power level was not changed but High frequency/Low frequency (HF/LF) ratio was decreased by Chamaecyparis obtusa essential oil (p<0.05), meaning that parasympathetic nervous system activity was not affected but sympathetic nervous system activity was decreased. These results indicate that Chamaecyparis obtusa essential oil has a modulatory effect on the autonomic nervous system activity.

• Journal of Nutrition and Health
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• v.31 no.2
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• pp.179-191
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• 1998

The satisfaction of elementary school children and their parents with the school lunch program by foodservice system was assessed by questionnaire. 787 (347 male, 417 female) 5th grade elementary school children and 761 parents participated. Foodservice systems of the schools were of 4 types : central/commissary ; satellite /commissary ; conventional/contracted ; and delivery/contracted. The most joyful mealtime for children was identified as lunch because of eating with friends. Satiety and leftovers after lunch varied according to the foodservice system. For example , there was less satiety in the contracted system and more leftovers in the delivery system than in the others, Foods tasted better in the commissary system than in the contracted one. The contacted system , especially the delivery/contracted system, was poor for keeping rice and soup hot. The children's food habits such as eating a greater variety of foods and good table manner were improved through the school munch program. Most parents well understood the main purpose of the school lunch program to be a source of education on nutrition and table manner, as well as a way in which to provide the same meals to all students and save the time & work needed to prepare home lunches. Parents claimed that hygiene, taste, good nutrition and food amount should be improved. This was especially true for hygiene in the commissary system and taste in the contracted system. Furthermore, they stressed that better taste and hygiene are the most important criteria for good school foodservice systems. In conclusion, parents wanted the school lunch program should be selected with consideration of children's preference such as by periodical food preference tests. A nutrition education program should also be provided to correct bad food habits of childrens.

• Journal of the Korean Society of School Health
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• v.6 no.2
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• pp.1-13
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• 1993

To develop new health management system for the school children in korea, we have made a descriptive study in two phases. The first phase was to find out the situation and the problems of current school health management system. The second phase was to propose a new system based on the findings through literature review. We found that the health screening examination was carried out inefficiently in many aspects, i.e. procedure, items and methods of screening. We proposed a new health management system which was more efficient, less expensive, and more reliable.

• 한국초전도학회:학술대회논문집
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• v.16
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• pp.48-48
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• 2006

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3313-3317
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• 2010

A simple and efficient synthetic route for making purpurin-18-N-aminoimides is described. The purpurin-18-Naminoimides are obtained by treatment of purpurin-18 methyl ester with various amines. These new compounds have long wavelength absorptions in the range of 706 - 711 nm. In preliminary screening, the purpurin-18-N-aminoimides have shown promising photosensitizing activity for the cancer cell by in vitro study in photodynamic therapy.

• Journal of the Korean Institute of Rural Architecture
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• v.8 no.3
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• pp.43-50
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• 2006

Educational environment that change rapidly, trial and error of system, breakdown of school environment by this and private education expense increase etc. are big social problem that we are facing present. Government is enforcing recognizing these problems and develops various program but the change and expansion of school facilities to achieve various program such as those are still unprepared. Now, important agenda that is lifelong education concept that is always can reeducate with social problem such as school leaving is come to the fore. So, specification high school for vocational education and alternative education cope in educational system and educational environment that is changed newly in existent school system. As the beginning step of the purpose of research, this study compares the attempt of school types and change of the school operation system for alternative education by between Korea and Japan and survey some regional cases. And the specification high school for alternative education which correspond to changed educational environment newly and architectural planning of educational facility that can activate those will be done. Also, this study aims that propose basic data that raise school facilities and educational environment by establishing guide line of optimum facilities for specification high school that wish to reorganize again or establish newly using existent school facilities and presents.