• Imaging Science in Dentistry
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• v.52 no.4
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• pp.343-350
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• 2022

Purpose: This study evaluated the prevalence of dental implant positioning errors and the most frequently affected oral regions. Materials and Methods: A sample was obtained of CBCT images of 590 dental implants from 230 individuals who underwent diagnosis at a radiology center using cone-beam computed tomography from 2017 to 2020. The following variables were considered: thread exposure, violation of the minimum distance between 2 adjacent implants and between the implant and tooth, and implant contact with anatomical structures. Descriptive data analysis and the Pearson chi-square test(P<0.05) were performed to compare findings according to mouth regions. Results: Most (74.4%) of the 590 implants were poorly positioned, with the posterior region of the maxilla being the region most frequently affected by errors. Among the variables analyzed, the most prevalent was thread exposure (54.7%), followed by implant contact with anatomical structures, violation of the recommended distance between 2 implants and violation of the recommended distance between the implant and teeth. Thread exposure was significantly associated with the anterior region of the mandible (P<0.05). The anterior region of the maxilla was associated with violation of the recommended tooth-implant distance (P<0.05) and the recommended distance between 2 adjacent implants(P<0.05). Implant contact with anatomical structures was significantly more likely to occur in the posterior region of the maxilla (P<0.05). Conclusion: Many implants were poorly positioned in the posterior region of the maxilla. Thread exposure was particularly frequent and was significantly associated with the anterior region of the mandible.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.224-224
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• 2015

The East Asia monsoon is one of the most complex atmospheric phenomena caused by Land-Sea thermal contrast. It plays essential role in fulfilling the water needs of the region but also poses stern consequences in terms of flooding and droughts. This study analyzed the influence of Global Sea Surface Temperature Anomalies (SSTA) on occurrence of droughts in the East Asia monsoon region ($20^{\circ}N-50^{\circ}N$, $103^{\circ}E-149^{\circ}E$). Standardized Precipitation Index (SPI) was employed to characterize the droughts over the region using 30-year (1978-2007) gridded rainfall dataset at $0.5^{\circ}$ grid resolution. Due to high variability in intensity and spatial extent of monsoon rainfall the East Asia monsoon region was divided into the homogeneous rainfall zones using cluster analysis method. Seven zones were delineated that showed unique rainfall regimes over the region. The influence of SSTA was assessed by using lagged-correlation between global gridded SSTA ($0.2^{\circ}$ grid resolution) and SPI of each zone. Sea regions with potential influence on droughts in different zones were identified based on significant positive and negative correlation between SSTA and SPI with a lag period of 3-month. The results showed that SSTA have the potential to be used as predictor variables for prediction of droughts with a reasonable lead time. The findings of this study will assist to improve the drought prediction over the region.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2011.04a
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• pp.97-102
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• 2011

The characteristics of traditional Thai houses are post-and-beam structure, lifted floor on pillars, and gabled roof as like as houses in other Southeast Asia countries. However 'charn', connective terrace among each room, is the most unique element in Thai houses which make the area under the 'charn' cool and useful. In Thailand, there are number of housing types caused by historic, social, cultural and geographic factors. This research is focused on comparative study of planning of traditional Thai houses of central and northern region, which have the biggest differences in between. Thai traditional house in central region has symmetrical arrangement on layout and when family members are added, they extend 'charn' and attach another building. While in Northern region, the 'charn' is located not in the center and in the front, and the direction of the main building is perpendicular to the length direction of the veranda. This research has a limitation to be generalized because just two region in Thailand were analyzed and the numbers of case studies were few. Nevertheless, we expect this paper to be a primary guidance to understand Thai traditional houses and we also expect that our research area will cover the all areas in Thailand and finally expand to conclude the commonality and diversity of traditional houses in Southeast Asia in the future.

• Environmental and Resource Economics Review
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• v.13 no.3
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• pp.367-385
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• 2004

This study offers the possibility of water allocation between upstream and downstream regions by side payment. In the case of river water, water use of an upstream region affect a downstream region's water use but not vise versa. In this case, the downstream region wants to secure stable water by suggesting side payment to the upper region. We examine the maximum compensation of the downstream region for acquiring additional water. Also we compare each region's total benefits between the cases with and without cooperation. The result of empirical study show that there was a Pareto improvement when two region cooperate in the water use. Also the amount of side payment depend on the degree of shortage of water and both regions are satisfied with the water allocation result by voluntary negotiation.

• Journal of Korean Society of Rural Planning
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• v.16 no.3
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• pp.67-76
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• 2010

The objective of this study is to investigate a priority and selection of agricultural specialization items from Daegu and Gyeongbuk region by using analytical tools such as, the Analytic Hierarchy Process(AHP) and the Scoring Method. The results of this study are as follows; 1) Five major items were selected for each region based on Daegu and Gyeongbuk regional agricultural performances. 2) The results of AHP analysis, Daegu and Gyeongbuk's agricultural experts evaluated the weight of three decision-elements(objectiveness 0.35, efficiency 0.341, identity 0.309) and seven decision-elements. 3) Results of AHP and Scoring Method analysis, Investigated a priority of agricultural specialization 3 items in 25 cities and districts Daegu and Gyeongbuk regional agricultural performances. 4) Finally, The results of this study will provide basic information on agricultural specialization policy in Daegu and Gyeongbuk region.

• Journal of the Korean association of regional geographers
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• v.2 no.1
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• pp.1-24
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• 1996

This paper is a case study on regional linkages of producer services in Chinju region. Producer service appeared as the most rapid growth sector in service industry. In Chinju region. manufacturing firms purchase generalized producer service within the region. However the higher-order service, they demand; the remoter metropolis especially Seoul, they depend on. Linkage patterns among manufacturing sectors are similar; but then the firms whose managers are from Chinju or Gyeong-nam region had stronger regional linkages than others. Public institute such as Chamber of Commerce & Industry, University Research Institute of Industrial Technology. Korea Technology Credit Guarantee Fund, Korea Silk Research Institute have made important role as suppliers of public producer services in Chinju Region. As present stage, their services of industrial technology, fiancing, and information are not only fit regional demand but also spatially limited within region. The facts that large firms purchase high-order services from other region and small firms have not good demand of producer service suggest regional policy implication about supplying relevant producer service in the region.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.281-286
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• 2006

In this study, acquired time series Landsat TM/ETM+ image to extract land surface temperature for wide-area region and executed geometric correction and radiometric correction. And extracted land surface temperature using NASA Model, and I achieved the first correction by perform land coverage category for study region and applies characteristic emission rate. Land surface temperature that acquire by the first correction analyzed correlation with Meteorological Administration's temperature data by regression analysis, and established correction formula. And I wished to improve accuracy of land surface temperature extraction using satellite image by second correcting deviations between two datas using establishing correction formula. As a result, land surface temperature that acquire by 1,2th correction could correct in mean deviation of about ${\pm}3.0^{\circ}C$ with Meteorological Administration data. Also, could acquire land surface temperature about study region by relative high accuracy by applying to other Landsat image for re-verification of study result.

• Journal of the Korean Society of Safety
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• v.28 no.6
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• pp.36-41
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• 2013

Previous study showed that delamination region in concrete structures can be successfully visualized using mode shapes of delaminated concrete section. However, modal tests for this purpose to obtain mode shapes of the delaminated concrete section may not be applicable in practice since, to correctly obtain the mode shapes of the section, the location and the shape of the delamination region in a structure should be known in advance. Unfortunately those are normally unknown in a real structure. Therefore, a moving forward test method may be useful to obtain the mode shapes of the concrete section when the location and the shape of the delamination region are not known. In this study, impact-echo testing based mode shape estimation technique is proposed and experimentally validated for visualization of delamination region.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.38
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• pp.199-205
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• 1996

The purpose of this study, therefore, was to construct the region statistical information to present methods of the data. The results of this paper are as follows: First, the construction of region statistical data is much in need of utilizing the server of regional information center, or the database to the server of public institutions, Second, there are some difficulties to receive the region statistical data because of only depending on the main source of KOSIS provided by national units from National Statistical Office. Third, as there is another problem which is text searching system served by KOSIS, GU system should be established for the user's satisfaction served by easier accessing screen. Fourth, there should be a standard software production to suit for the accessing software of the region statistical data.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.4
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• pp.175-182
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• 1994

In this study, we present unvoiced consonant recognition system using characteristic parameters of the phoneme of the each syllable. For the recognition, the characteristic parameters on the time domain such as ZCR, total energy of the consonant region and half region energy of the consonant region, and those on the frequency domain such as the frequency spectrum of the transition region are used. The objective unvoiced consonants in this study are /ㄱ/,/ㄷ/,/ㅂ/,/ㅈ/,/ㅋ/,/ㅌ/,/ㅍ/ and /ㅊ/. Each characteristic parameter of two regions extracted from these segmented unvoiced consonants are used for each recognition system of the region, independently, And complementing two outputs of each other system, the final output is to be produced. The recognition system is implemented using MLP which has learning ability. The recognition simulation results for 112 unvoiced consonant samples are that average recognition rates are 96.4$\%$ under 80$\%$ learning rates and 93.7$\%$ under 60$\%$ learning rates.