• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2334-2340
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• 2010

Sun position computed by Michalsky shows maximum $1.5^{\circ}$, $0.88^{\circ}$ and 2 minutes differences in azimuth, altitude, and sunrise and sunset times respectively compared with Korean Almanac. The 2-axis solar tracking system, which consist control panel with ATmega128 CPU, BLDC motor-cylinder actuator and 2-axis link mechanism, was developed. Computed azimuth and altitude of sun for a current time, and latitude and longitude of tracker position built are controlled in real time by BLDC motor-cylinder actuators comparing with the position feed-backed by Hall sensor. The use of BLDC motor is free in maintenance. Implementation of a home-return function by Hall sensor is to minimize the cumulative error.

• Resources Recycling
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• v.14 no.2
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• pp.56-61
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• 2005

Economic feasibility for retrofitting the wet bottom ash handling system to the dry system in a existing 500MW${\times}$2 units pulverized coal thermal power plant in Korea was studied. Replacing to the dry system requires the initial capital costs of 13,415,127,000\, and saves the operating costs of 935,345,000\ per year. Economic analyses based on these results showed that the initial capital cost would not be recovered within the service life of the facilities at the interest rate of 10%, and the internal rate of return of 5.6% were obtained. Thus, the retrofitting to the dry system was not economically favorable in the current condition. However, the retrofitting would be profitable when the ash disposal cost and ash selling price were increased over 15,000\/MT or 17,000\/MT, respectively.

• Journal of Korean Society of Rural Planning
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• v.12 no.4 s.33
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• pp.63-76
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• 2006

This research tried to present some basic data necessary to give effective support to urban retirees who already returned to the farm by looking into factors effecting on their adjustments to the lives before they returned to the farm and after they did so to know how well they adapt to the rural lives. For the purpose, we made a survey of 408 returners to the farm over the age of 50 for 6 days from October 18 to October 23 in 2004 using questionaires. The results show the followings. First, there are significant difference in the satisfaction with the rural life occurred by the sociological demographic changes according to 'health condition', 'subjective economic ability' and 'previous job'. Second, the difference of satisfaction with the rural lift which was taken place by the reasons before they moved to the farm is effected considerably by what made them decide to return to the farm first whether they prepared for it or not and how much money they have to do so. Therefore, to succeed in adjustment to the rural lives, their decision should be made by positive causes, they have to prepare concretely for it before they carry out their plans and they had better have enough money to move. Third, the difference of satisfaction with the rural life occurred by the reasons after they moved to the farm is effected by 'satisfaction with the forming information', 'the number of friends or neighbors', 'the frequency of meeting the friendly', 'the level of intimacy with neighbors' and 'their efforts to improve the relations with other residents'. And the sensitiveness to perceive the inconvenience according to the rural life is related strongly to the satisfaction with the rural life in the above 6 areas. Fourth, the repression analysis implemented to find how much the above 3 factors effect on the satisfaction with the rural life shows that it is 'returner's current health condition', 'farming education', 'farming fund' and 'effort to be intimate with other residents' that are very important.

• Korean Journal of Remote Sensing
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• v.25 no.6
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• pp.547-557
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• 2009

LIDAR (LIght Detection And Ranging) is an active remote sensing technology which provides 3D coordinates of the Earth's surface by performing range measurements from the sensor. Early small footprint LIDAR systems recorded multiple discrete returns from the back-scattered energy. Recent advances in LIDAR hardware now make it possible to record full digital waveforms of the returned energy. LIDAR waveform decomposition involves separating the return waveform into a mixture of components which are then used to characterize the original data. The most common statistical mixture model used for this process is the Gaussian mixture. Waveform decomposition plays an important role in LIDAR waveform processing, since the resulting components are expected to represent reflection surfaces within waveform footprints. Hence the decomposition results ultimately affect the interpretation of LIDAR waveform data. Computational requirements in the waveform decomposition process result from two factors; (1) estimation of the number of components in a mixture and the resulting parameter estimates, which are inter-related and cannot be solved separately, and (2) parameter optimization does not have a closed form solution, and thus needs to be solved iteratively. The current state-of-the-art airborne LIDAR system acquires more than 50,000 waveforms per second, so decomposing the enormous number of waveforms is challenging using traditional single processor architecture. To tackle this issue, four parallel LIDAR waveform decomposition algorithms with different work load balancing schemes - (1) no weighting, (2) a decomposition results-based linear weighting, (3) a decomposition results-based squared weighting, and (4) a decomposition time-based linear weighting - were developed and tested with varying number of processors (8-256). The results were compared in terms of efficiency. Overall, the decomposition time-based linear weighting work load balancing approach yielded the best performance among four approaches.

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.141-148
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• 2021

Project management is a current trend of management in the public sphere, based on different principles, methods and tools. The tools include information technologies providing control over time, cost, quality and planning process in order to ensure accountability to interested parties. The goal of the research was to examine the impact of the integration of information systems in project management of the public sphere on the quality of public governance and administration using the example of infrastructure projects involving the private sector in developing countries. The methodology of the research is based on the concepts of "digital-era governance" (DEG), "Information governance" and "project governance" to determine the effectiveness of information systems and technologies in the management of infrastructure projects in the public sphere. The data from the countries with Lower middle income (India, Indonesia, Philippines, Ukraine, Vietnam) and Upper middle income (Argentina, Brazil, China, Colombia, Mexico, Peru, Romania, Russian Federation, Thailand, Turkey) for 1996-2020 were used to study the effects of DEG. The results show two main trends in the countries with Lower middle income and Upper middle income. The first trend is the development of digital governance, the concept of "digital-era governance" through information systems and performance measurement of the governance system, forecasting of investment flows of infrastructure projects, measurement of payback and effectiveness parameters for investment management in the public sector, decision support. The second trend is the existence of systemic challenges related to corruption, social and institutional factors through the development of democracy in developing countries and the integration of NPM similar to developed countries. The confidence of interested parties, especially private investors, in public authorities is determined by other factors - the level of return on investment, risks and assignment of responsibility, probability of successful completion of the project. These data still remain limited for a wide range of project participants, including citizens.

• Journal of Information Technology Services
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• v.20 no.6
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• pp.45-62
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• 2021

After the COVID-19 outbreak in 2019, the spread of COVID-19 has not been easily caught despite preventive measures in each country. The spread of COVID-19 has hit the world, especially in the economic and tourism sectors. Countries around the world are easing restrictions on the movement of vaccinated people in preparation for the post-corona era. Under the name of "Vaccine Passport," "Vaccination Certificate," and "Digital Health Pass," vaccination measures are being implemented to allow vaccination recipients to use multi-use facilities. However, there is no international agreement on the movement of countries, and each country has its own immigration policy. In order to return to pre-corona daily life, global agreements must be reached from the movement of vaccinated people between countries, and standards and implementation methods must be determined. This study focuses on the implementation and utilization of vaccination certificates suitable for the COVID-19 era. We will look at the spread of COVID-19 and its international response policies. In the case of COVID-19, we will investigate why vaccination certificate installation should be standardized and how far the current standardization has been discussed, and discuss the characteristics of vaccination certificate installation and considerations. In order for the immunization certificate discussed in the previous chapter to be recognized internationally, institutional and technical considerations are identified and security factors that may occur in each implementation are also presented. Finally, the international recognition case of vaccination certificate is discussed, and the method of installation and utilization of vaccination certificate is proposed. This paper can be used as a policy because of its timeliness in studying the standards of vaccination certificates and considerations for international recognition to restore movement between countries in the spread of COVID-19. In addition, if other infectious diseases occur in the future or similar cases where movement between countries is restricted, it can be used as a reference to support the movement of verified people.

• International Area Studies Review
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• v.15 no.2
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• pp.25-47
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• 2011

The paper will investigate the chances of progress in the peace process in Middle East. Robert Hazo's 1993 article mainly argued the Palestinians and Syrian problems. He saw that these two problems are one of the key issue that current Middle East problem which involves Israel. The key tenants of his argument will be dissected to assess whether this view holds true in the light of developments in the Middle East in the intervening years. The Arab-Israeli struggle remains one of the most intractable in history. In 1993 Robert Hazo concluded that 'the conflict is a terminal struggle'. This paper investigates his analysis in light of progress or lack of in the intervening period and against the contemporary strategic environment. It uses information presented in academic, government, newspaper and world wide web articles to conclude that Hazo's assessment remains valid. While the various talks since 1993 combined with the potential benefits the United States, Israel and Syria could gain from a settlement proffer hope, the issue of 'right of return, borders and Jerusalem are unlikely to be bridged in the near future.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.2
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• pp.75-81
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• 2019

In this study 24 power transmission towers were selected by considering various variables such as power transmission capacity, height and structural type to evaluate their seismic performance using the standard design response spectrum recently announced by the government. In addition, the stresses and sectional forces generated by the current design wind loads and revised seismic ones were compared to review the effects on the design of power transmission towers when the government-required seismic standards were raised. The results of seismic performance evaluation for the target power transmission towers showed that they had seismic capacity of 0.31~0.91g, and that they met the level of the earthquake-resistant special grade, which is the 2,400-year earthquake return periods and secured seismic safety. Further, the sectional forces caused by earthquakes in the towers were 33~82.5% of the ones due to wind loads, and it was also confirmed that the design wind loads were more dominant than design earthquake ones under the elevated seismic standards.

• International Area Studies Review
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• v.20 no.3
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• pp.101-121
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• 2016

This research is purposed to analyze the effect of firms' current socially responsible management on the future corporate financial performance with specified areas of socially responsible management according to the beneficiaries. Tobin's Q statistic and return on assets are calculated and exploited as measures of corporate financial performance. as of empirical analysis results, we found that the social contributions in the consumer area and external social contribution at time t influence the Tobin's Q statistic at time (t+1) in the aggregate analysis. as it is revealed that there is no effect in the firms with the outstanding social performance to the future corporate financial performance, we understand that the capital market is very sensitive to the external social contribution including consumers of firms with the weak social performance rather than the social contribution of socially outstanding firms. This sensitivity of capital market can effectively enhance the social contribution of firms, in particular listed firms with the weak social performance.

• The Korean Journal of Archival Studies
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• no.57
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• pp.5-33
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• 2018

Records, especially the authentic records the nation secured, have an ontological feature of proof that is able to persuade the current present of the past present, and inherent in it is faith that originates from fundamental objectivity. Therefore the image of silence that such strictness of records creates realizes the detonation of specific memories through the act of visual exhibition. This research started from the notion that records achieve social vitality and return through its exhibition, as well as the critical awareness that it 're-mediate' the past and memory through interactions with image. The reason for viewing the archival exhibition as the subject of user analyzation is that in the process where exhibition sorts and arranges records, it is the tool and mediation that most distinctly exposes the identity of the archives. Hence, this research first analyzes national archives, particularly the exhibition of "presidential" records, which is in the center of memory conflict, in the viewpoint of the cultural practice of memory. Afterwards, it discusses empirical research and results on how users accept and resist the meaning of the exhibition through actual surveys of users after their viewing of an exhibition.