• Journal of Astronomy and Space Sciences
• /
• v.28 no.1
• /
• pp.1-7
• /
• 2011

Characteristics of latitude variations of sunspots in the northern and southern hemispheres are investigated using the daily sunspot area and its latitude during the period from 1874 to 2009. Solar magnetic activity is portrayed in the form of sunspot, regions of concentrated fresh magnetic fields observed on the surface of the Sun. By defining center-of-latitude (COL) as an area-weighted latitude, we find that COL is not monotonically decreasing as commonly assumed. In fact, small humps (or short plateaus) between solar minima can be seen around every solar maxima. We also find that when the northern (southern) hemisphere is magnetically dominant, COL is positive (negative), except the solar cycle 23, which may give a hint that these two phenomena are consistently regulated by one single mechanism. As a result of periodicity analysis, we find that several significant periodicities, such as, of ~5.5, ~11, ~49, and ~167 years.

• Journal of Korea Multimedia Society
• /
• v.19 no.7
• /
• pp.1116-1126
• /
• 2016

Image segmentation is widely used in the pre-processing stage of image analysis and, therefore, the accuracy of image segmentation is important for performance of an image-based analysis system. An efficient image segmentation method is proposed, including a filtering process for super-pixels, improved saliency map information, and a merge process. The proposed algorithm removes areas that are not equal or of small size based on comparison of the area of smoothed superpixels in order to maintain generation of a similar size super pixel area. In addition, application of a bilateral filter to an existing saliency map that represents human visual attention allows improvement of separation between objects and background. Finally, a segmented result is obtained based on the suggested merging process without any prior knowledge or information. Performance of the proposed algorithm is verified experimentally.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2003.09a
• /
• pp.36-45
• /
• 2003

Sensitivity analyses for several seismic source models were studied. For the area sources, the hazard is steeply decreasing with the source-to-site distance. Hazard is decreasing when the area of the source is increasing with fixed annual rate. For the fault sources, the fault length, distance from a site and dip angle of near fault show very sensitive effect to seismic hazard. But the various magnitude-rupture length relationships show effect to seismic hazard slightly. For the fault source with small magnitude, the exponential model is preferred rather than the characteristic model to the magnitude-recurrence law.

• The Journal of Korean Association of Computer Education
• /
• v.20 no.5
• /
• pp.69-77
• /
• 2017

In this paper, we analyzed the difference of ICT literacy which can show the educational power of students in the field of information. As a result, the average score of ICT literacy test by elementary school was high in the order of big city, small city, rural area. In case of middle school, the score was high in the order of small city, big city, rural area. ICT literacy in elementary and middle schools differed according to the size of the region. However, in both elementary and middle schools, the scores of rural students were lower than those of urban students. Therefore, it need the policy of ICT education for students of rural area. And, as the ICT literacy level gap between urban and rural students is concerned, it is necessary to develop an education program for this. This study is meaningful as a basic data on the necessity of systematic ICT literacy education policy according to school and region characteristics.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.14 no.1
• /
• pp.69-80
• /
• 1996

This Study aims at identifying optimum residential area of small and medium local cities to be relocated in the future. In the object of study, Chinju City was chosen and it consists of three stages of application to choose the priority of residential development us well as available residential locations. In the first stage, a digital image processing technique was applied to generate the existing urban land use information from the satellite image data. In the second stage, GIS technique was used to choose the avaliable residential area by evaluating the elements for residential site allocation such as road accessibility, topographic height, slope, aspect, legal limit, population density, and land price. In the third stage, some mathematical location models were applied to identify optimum candidates of residential areas chosen by earier stages. The results were evaluated by statistical methods and integer programming to identify the development priority. We expect this procedures and the results will be able to be used as a guide-line to support housing policies of Chinju City by allocating residential sites as well as a technique to apply a locational analysis for the future residential areas of small and medium local cities.

• Fire Science and Engineering
• /
• v.20 no.2 s.62
• /
• pp.54-63
• /
• 2006

The number of forest fire under various conditions such as year, month, time, day of the week, region, damaged species, cause, and damaged area are checked, and the statistics of the forest fire causing materials in recent 14 years ('91-'04) are analyzed. The result shows that the year majority of forest fires had happened in last 14 year was 2001 and most of forest fire occurred in April, Sunday, around 14:00 to 15:00. The most damaged region is Gyeongsangbuk-Do, followed by Gangwon-Do, Jeollabuk-Do, and Gyeonggi-Do. The most damaged species is pine tree. The main causes of forest fires are accidental fire and incineration of a field boundary; however, recently, incendiarism is increased. The result of analysis on the damaged area shows that small fires under 5 ha occurred most frequently and large fires (over 30 ha) occurred mostly in Kangwon province (44.2%). The result also shows that the large forest fires (1,113 minutes) require 7.5 time more than the small forest fires (148 minutes). Especially, since average damaged area caused by large forest fire was about 470 ha per incident.

• Journal of Korean Society of Rural Planning
• /
• v.28 no.2
• /
• pp.21-32
• /
• 2022

Since the village maintenance type public housing project was introduced in 2015, the resident needs for regional revitalization and pleasant living conditions are not being met due to the poor performance of the public housing complexes that reflect the surrounding area maintenance plan (village plan) and regional characteristics. The purpose of this study is to suggest a plan to revitalize the village maintenance type public housing project in consideration of regional characteristics as a result of analyzing the needs of local residents through the problems of the village maintenance type public housing project being promoted so far and resident satisfaction. As a result of the analysis based on the public housing project implementation status analysis and resident satisfaction, the plans to activate the village maintenance type public housing project are as follows. First, in order to secure the effectiveness of the village plan, it is desirable to promote the public housing project and the village plan at the same time. It is necessary to secure a budget according to the selection of public offering projects in the village plan, such as promoting public housing projects without setbacks by prioritizing land purchases for public housing sites and establishing specialized strategies considering regional characteristics. Second, a public housing project that responds to local demand is required. The evaluation factors such as continuous promotion of the urban architecture integration plan and strengthening of regional linkage plans such as specialization of regionally tailored designs should be supplemented so that regional resources and village plans are linked with the public housing specialization plan. Third, surrounding area maintenance plan (village plan) should be secured by the strengthen of the legal status or establishing related provisions. It is also necessary to promote system improvement for area maintenance plan (village plan) when selecting a publicly funded public project.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.11a
• /
• pp.6-11
• /
• 2007

Packaged power station (PPS) is a stationary diesel engine generator set and developed for the supply of electric power to small villages, islands and factories etc. Therefore, the PPS is closely installed to residence area and sometimes cause the environmental noise problems. In this paper, environmental noise analysis was performed for the power plant with 28 sets of PPS. The initial analysis results showed the some difference between the measurement and analysis because of the inaccurate noise source data. To improve the accuracy of analysis, main noise sources were inversely estimated using the in-situ measurement data in the vicinity of PPS and steam boiler. As the results of re-analysis, the good agreement was obtained and it was concluded that the noise levels exceed the specified noise limit in residence area. In order to reduce the noise, the several methods such as geometry alteration of inlet duct, application of hybrid-type silencer and noise protection barrier were suggested and verified with the confirmed analysis model.

• Korean Institute of Interior Design Journal
• /
• v.17 no.5
• /
• pp.141-149
• /
• 2008

This study aims to understand functional spaces within university dormitory, examine the influences of residential environment factors and personal characteristics on users' satisfaction through what parameters and probability among these parameters and seek improvement methods for dormitory users to live at dormitory as the best residential space through causal analysis of residential space uses at university dormitory based on such a probability. Research methods include theoretical research of architectural space characteristics of university dormitory facilities through literature survey, analysis of satisfaction with spaces and their uses through questionnaire and causal analysis of each residential environment factor after making route model using data obtained from the results of analysis. The results of this study are as follows. Factors affecting residents' satisfaction with cultural activities of residential environment factors are safety, territoriality, interior finishing and complexity and those affecting residents' educational activities are safety and amenity of space. Residential function space of university dormitory must have spatial planning that social activities including individual and small group culture and educational activities from the view of spatial territoriality and flexibility based on safety and amenity and facilities related to continuity and connection of common space and unit residential space should be decentralized rather than centralized.

• Journal of the Korean Society of Safety
• /
• v.33 no.5
• /
• pp.9-14
• /
• 2018

The piping system of a nuclear power plant plays a role of transferring high energy fluid to equipment and various devices. The safety and soundness of these piping systems are very closely related to the operability of the power plant. In the case of a welded part of a small diameter pipe, it may grow as a microcrack due to a lack of penetration, and it may grow to a size that affects the safety of the pipe due to the influence of mechanical vibration and fatigue load. Resonance refers to an increase in energy as the natural frequency of an object coincides with the frequency applied to the external force. When this resonance occurs, the frequency is the resonance frequency. In this study, when defects exist in the welds of small diameter pipe, the natural frequency of the pipe changes and resonance may occur. Since these resonances are likely to cause fatigue damage to the piping, resonance frequency changes due to the size and shape of the defects are analyzed and evaluated. As a result of the vibration test, the resonance frequency tended to decrease as the depth of the defect deepened, and the influence was larger when the defect existed at the bottom of the top of the trough. Also, it was confirmed that the Transverse cracks had an effect on the resonance frequency in the presence of the cracks in the weld bead, compared to the longitudinal cracks. As a result of this study, it is expected that the cause of the defect and the condition of the pipe can be monitored because the resonance frequency tendency according to the shape of the crack is analyzed.