• Journal of Broadcast Engineering
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• v.12 no.1 s.34
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• pp.11-27
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• 2007

T-DMB(Terrestrial-Digital Multimedia Broadcasting) for portable and mobile broadcasting service was officially launched in the metropolitan area of Korea in December 2005. The development of interactive data services and the expansion of T-DMB network have been now progressed, and the regional T-DMB broadcasters will be selected in the near future. Although it is important to evaluate service area and reduce a fringe area for optimizing RF coverage of T-DMB, there was no professional system to support those works, and therefore lots of resources in budget, manpower and time were required. The measurement considering characteristics of SFN(Single Frequency Network) is essential in the implementation of T-DMB network which needs to control synchronization, spacing and output power of transmitters. In addition, mobile measurement, enough measured parameters for many-sided analysis of reception quality, efficient management of enormous measured data and representation of measured results on the electronic map are also important in evaluating service area. In this paper, we derived requirements for a new measurement system in T-DMB by considering the above details, and we proposed and developed an integrated measurement and analysis system. The developed system was applied to the implementation of T-DMB network of KBS and field tests, and it proved its efficiency and accuracy in result.

• Cartoon and Animation Studies
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• s.12
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• pp.1-12
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• 2007

The long-term stagnation in the country involving missing it is starting from the late 1990s accumulated on the common vision. The government has, since 2002, cartoon comics industry nurture long-term industrial development of five-year plan, 346.7. During that period of unprecedented material support to the government's sweeping received. Upcoming in 2008 is the second long-term development plan will be effective. The temperature inside and outside the government, however, various tax and go to feel quite differently. The first plan is merely a period of enforced projects listed are only fit for Panathinaikos has endorsed this general trend, yirugo diagnosis. But fundamentally, the exact diagnosis is necessary for the long-term stagnation. Children's Learning Results cartoon wepmanhwawa not thrive households. Comics readers about the consumption pattern is changing. Therefore, long-term plan for the development of cartoon industry only a few government budget plan is not the government write 73 gala, companies and the private sector are coming together to plan and worry that the plan should be a comprehensive and bevels. In addition, through the selection and concentration to increase efficiency. You will probably need to strengthen the capabilities of our private organizations, it is a priority. Furthermore, the government's financial and policy support for the lobbying power also lead to an increase in betting. It features a think tank to study the policy framework for the establishment and promotion assume the ultimate proposal includes a cartoon film cozy confines of the legislation that parallels activities in the various proposals.

• Current Photovoltaic Research
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• v.4 no.3
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• pp.108-113
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• 2016

III-V compound semiconductor based thin film solar cells promise relatively higher power conversion efficiencies and better device reliability. In general, the thin film III-V solar cells are fabricated by an epitaxial lift-off process, which requires an $Al_xGa_{1-x}As$ ($x{\geq}0.8$) sacrificial layer and an inverted solar cell structure. However, the device performance of the inversely grown solar cell could be degraded due to the different internal diffusion conditions. In this study, InGaP/GaAs double-junction solar cells are inversely grown by MOCVD on GaAs (100) substrates. The thickness of the GaAs base layer is reduced to minimize the thermal budget during the growth. A wide band gap p-AlGaAs/n-InGaP tunnel junction structure is employed to connect the two subcells with minimal electrical loss. The solar cell structures are transferred on to thin metal films formed by Au electroplating. An AlAs layer with a thickness of 20 nm is used as a sacrificial layer, which is removed by a HF:Acetone (1:1) solution during the epitaxial lift-off process. As a result, the flexible InGaP/GaAs solar cell was fabricated successfully with an efficiency of 27.79% under AM1.5G illumination. The efficiency was kept at almost the same value after bending tests of 1,000 cycles with a radius of curvature of 10 mm.

• Journal of Astronomy and Space Sciences
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• v.24 no.1
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• pp.69-78
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• 2007

The international EARTHSHINE mission is to measure 1% anomaly of the Earth global albedo and total solar irradiance using Amon-Ra instrument around Lagrange point 1. We developed a new ray truing based integrated end-to-end simulation tool that overcomes the shortcomings of the existing end-to-end performance simulation techniques. We then studied the in-orbit radiometric performance of the breadboard Anon-Ra visible channel optical system. The TSI variation and the Earth albedo anomaly, reported elsewhere, were used as the key input variables in the simulation. The output flux at the instrument focal plane confirms that the integrated ray tracing based end-to-end science simulation delivers the correct level of incident power to the Amon-Ra instrument well within the required measurement error budget of better than ${\pm}0.28%$. Using the global angular distribution model (ADM), the incident flux is then used to estimate the Earth global albedo and the TSI variation, confirming the validity of the primary science cases at the L1 halo orbit. These results imply that the integrated end-to-end ray tracing technique, reported here, can serve as an effective and powerful building block of the on-line science analysis tool in support of the international EARTHSHINE mission currently being developed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.443-452
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• 2016

Six preservice teachers who participated in the "2016 service of summer vacation daycare programs by university and college students" focused on the programs for the formation of art, music and physical education and recreation culture were selected as research participants. The meaning of the experience they had through the service process was qualitatively analyzed. The subjects accepted the purpose of the self-directed service in which they should themselves solve a series of the entire process, from planning a volunteer program through drawing up the budget and purchasing materials to practice, evaluation and expressed the intention of participation. A volunteer program was conducted including visiting a daycare program for lower graders of elementary school (1st and 2nd grades) with more than 40 class hours during vacation. As research materials, research participants' journals, transcripts of individual interviews and group interviews, transcripts of phone calls, e-mail messages, and self-evaluation records of each class hour were collected. To increase the reliability and validity of the study, triangulation, member check, advice and review of the experts were conducted. In the study results, the volunteering experience-related significance for the preservice teachers who participated in the self-directed service were broadly categorized into 'Becoming a capable professional teacher', that consists of 'Increasing the power of thinking', 'Realizing the importance of communication', 'Doing together itself is important' and 'Ability to apply information and resources is needed'. 'Increase the continuity between preschool and elementary education' was subdivided into 'Get to know the necessity of the continuity between preschool and elementary education' and 'Want to learn the continuity between preschool and elementary education.'

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.5 no.1
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• pp.37-84
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• 1981

Korean private colleges under the period of Japanese control was the kernel for the educational resistance, one of the save-the-nation movements because of inculcating in Koreans the spirit of independence and self-respect under that period. Posung College Library building, erected in Commemoration of the 30th Anniversary of the Foundation, especially, was the result of Koreans systematizing ability and iron will of independence for the future generations. In this paper, an attempt to study the Korean private college libraries under the period of Japanese control is provided. The main institutions in this study are Posung College library, Chosen Christian College library (Yunhee College Library), and Ewha College Library. This study will focus to review the followings: 1. The historical background of above mentioned libraries. 2. The educational resistance under that period. 3. The comparative and analytical study of these private college libraries and Keijo Imperial University library. 4. The facilities and the basic collection development plan on the basis of presentation. 5. library services including readers services. 6. The impact of these libraries on the present private university libraries. 7. The organization and staffing pattern, and budget of these private college libraries. The followings are the outlines conclusions: 1. Korean private college libraries had been established in order to perform the educational resistance. They are one of the supporting agencies for the research activities, among the most important means of social education, and provide, no doubt, the full nutriment for hungry soul under that period. 2. These libraries have not outstripped Keijo Imperial University in collection of books as well as man power, but their collection of books coincided, in general, with their curricula, and had feature to perform the save-the-nation-movement by education. 3. The library services were appeared in the forms such as the Circulation Library, Lectures on the Use of Books and Libraries, Library Week, and Training Course for the Librarians, etc. It is thought that these activities contributed to the social and cultural development of Korea indirectly. 4. The library administration of the private colleges depended upon the director of library because of the frequent changes of staffs and the simple functional system without its middle class. 5. The Japanese Government-General in Korea gave no financial assistance to the private colleges though they were in financial difficulties more than Keijo Imperial University. 6. The ambitious ideal for foundation of universities in reality as well as in name was not achieved during that period because of the monstrous obstacle so-called the Japanese Government-General in Korea, but its ideal had a desirable effect upon these college libraries development, in particular, before and after 1935.

• Journal of Advanced Navigation Technology
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• v.18 no.1
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• pp.84-89
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• 2014

Worldwide Interoperability for Microwave Access (WiMAX) is an efficient technology for 20th century communication system. The technology provides broadband speed without the need for cables and is based on the IEEE 802.16 standard(also called Wireless MAN). Mobile WiMAX is defined as IEEE802.16e which is advanced and efficient technology for mobile telecommunication rather than GSM, CDMA technology. In this work link budget calculation for WiMAX have been done. Cell range have been calculated over digital modulations and they are BPSK, QPSK and QAM. Here different types of models like Cost 231 model have been used for different types of areas like open, rural and urban areas and Erceg-Greenstein model for sub-urban areas. Effect of various parameters like frequency, base station antenna height, transmission power and SNR over cell range have been studied. Analysis have done for both uplink and downlink.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.11
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• pp.984-997
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• 2015

Chang'e-3 consisting of a lunar lander and exploration rover was launched on December 1, 2013 aboard a Long March 3B rocket flying from Xichang space launch center. Chang'e-3 was inserted into the lunar orbit after about a 5-day transit to the Moon and landed on the targeted landing site after orbiting around the Moon for 8 days. The successful landing of the Chang'e-3 gives a lot of help to analyze the future needs of the subsystem technologies and to figure out the trajectory from launch to lunar landing as well as operation sequences in the development of Korean lunar exploration is scheduled. Therefore, the configuration and analysis of overall mission of Chang'e-3 is performed based on the public information from the press and website. As a result, overall mission trajectory is reconstructed by solving boundary condition and then estimating control variable. Visibility status and eclipse status also analyzes so communication and power charge condition is as good as to operate lunar lander. Mass budget of the lander is derived using ${\Delta}V$ according to specific impulse.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.9 no.1
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• pp.153-179
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• 1998

This study attempt to suggest a policy for the effect of using in the public libraries by the verification that are different between groups by their using patterns and types of book collections. by using patterns and system of desired-book for user. by using patterns and system of desired-book for user. The questionnaire is distributed to the delivery lending library's user and librarian in public libraries. The summary of results are as follows 1 The Circulation period of public library is one month per every delivery lending library. 2. The Circulation volume of public library is '100-200' books per every times. 3. There are significant differences by their using patterns and types of book collections. 4. There are significant differences by their using patterns and system of desired-book for user. 5. There are significant differences by their using patterns and placement of book collections. Their results show that library is most effective place of book collection services. 6. Circulation services must carry out only in the sphere of jurisdiction 7. A Lost books must set up treatment basis of natural reduction ratio 8. The Interference factors of delivery lending library are lacks of human power, lost books and negative attitute of user in order 9. The Effects of using a delivery lending library are a positive attitute and specialty of top management, the optimum of budget and the effect of deposit system 10. Natural reduction ratio of lost books appropriates 0.5-0.6% of total loaned books

• Korean Journal of Community Nutrition
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• v.4 no.1
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• pp.83-94
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• 1999

This study was carried out to investigate the general characteristics of public health nutritionists, the current status of nutrition services operation, the recognition about nutrition services of public health center related man power, the job satisfaction and self-assessment and the need for a retraining course of public health nutritionists. The subjects were 58 public health nutritionists who responded to the questionnaire distributed at the annual retraining program in 1998. The results of this study are summarized as follows. 1) 46.5% of the nutritionists were 26-30 years old, 62.1% were 4 year university graduates 74.1% were food and nutrition majors and 51.7% were daily workers. 2) Among the public health center-related manpower, the recognition about nutrition services was the highest for the manager of family health section, followed by the head of public health centers, and then the general nurse in public health centers. 3) The ranking of the reasons for job satisfaction of the public health nutritionists was, relationship with colleagues(3.84), inhabitants response after nutrition counselling(3.53), specialized value realization/conviction about duty(3.35), contents of the work(3.10), value achievement(3.08), self achievement/development(3.00), self discretion(2.92), participation in policy decisions(2.90), work load(2.75), chance of retraining and acquisition of new information(2.73), working environment(2.69), supervisio $n^port by superiors(2.67), salary(2.38), supply of necessary education material, technique(2.37), and budget security(2.22). 4) The satisfaction of the inhabitant's responses after nutrition counseling was the highest among the 4 year university graduates(p<0.05), the satisfaction of the specialized value realization/conviction about duty was the highest among the nutritionists 26-30 years old(p<0.05). Food and nutrition majors(p<0.05) and those having worked less than 3-5years at public health centers also showed much satisfaction(p<0.05). Satisfaction with the salary was the lowest among the food and nutrition majors(p<0.01) and daily workers(p<0.001). The satisfaction with the participation in policy decisions was the lowest among the daily workers(p<0.01). 5) The ranking for the level of self-assessment were, nutrition and dietetic practice(2.92), communication(2.80), management(2.77), public health science and practice(2.66)(p<0.01). The general characteristics such as the level of education, major, employment condition, current public health center's tenure, and charge experience of the nutrition guidance work were not significantly related to self-assessment except the management part(p<0.05). The higher the satisfaction of specialized value realization/conviction about the duty, the better the total score on the self-assessment(p<0.05)..