• Journal of the Optical Society of Korea
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• v.19 no.6
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• pp.687-694
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• 2015

A photoluminescence (PL) imaging method using a vision camera was employed to inspect InGaN/GaN quantum-well light-emitting diode (LED) epi-wafers. The PL image revealed dark spot defective regions (DSDRs) as well as a spatial map of integrated PL intensity of the epi-wafer. The Shockley-Read-Hall (SRH) nonradiative recombination coefficient increased with the size of the DSDRs. The high nonradiative recombination rates of the DSDRs resulted in degradation of the optical properties of the LED chips fabricated at the defective regions. Abnormal current-voltage characteristics with large forward leakages were also observed for LED chips with DSDRs, which could be due to parallel resistances bypassing the junction and/or tunneling through defects in the active region. It was found that the SRH nonradiative recombination process was dominant in the voltage range where the forward leakage by tunneling was observed. The results indicated that the DSDRs observed by PL imaging of LED epi-wafers were high density SRH nonradiative recombination centers which could affect the optical and electrical properties of the LED chips, and PL imaging can be an inspection method for evaluation of the epi-wafers and estimation of properties of the LED chips before fabrication.

• Journal of Korean Institute of Industrial Engineers
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• v.19 no.2
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• pp.53-64
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• 1993

Successful completion of a visual task in a predetermined time is very crucial to many operations such as piloting an aircraft. Although existing ergonomic interface models often provide a function of vision tests, it determines only the visibility at any given location. To complement this problem in existing models, the isoresponse time region considering the factors related to visual tasks is presented. Using a multiple regression model, equal response time regions were obtained within which mean response time is expected to be the same and is asymmetrical in shape. Among the factors considered, expectancy significantly decreased response time, and when cued, the effects of field heterogeneity, target uncertainty, density, size contrast and peripheral position on search time were less significant than those in unexpected cases. Response time and error rate, gender and visual acuity were not significantly correlated, and response time and age was positively correlated. These results are expected to be directly applicable to designing various visual tasks in real-life situations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1968-1975
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• 2011

This study was performed to propose a development guide for the periphery of local industrial park in the region of Hongseng-gun located at the mid-west of Chungnam province., which is a representative agrarian society, has been approached to a super-aged society where the region shows a continuous decrease in population, and the composition ratio of old ages is about 17.1%. Also, the region is a period of a low ebb due to the traditional agriculture based industrial structure in producing mainly simple productions. Many local governments in agrarian and fishing regions have been efforted for luring some businesses in their regions by constructing industrial complex competitively in order to solve such structural problems in such local regions. However, in some cases, these efforts cause certain destructions in the local original natural environment due to such development of industrial complex and the decrease in the settlement environment of residents. The objective of this study is to establish a local development plan for building the sustainable and comfortable settlement environments based on the settlement of the residents and the labors in such industrial complex by preventing sprawl developments in the construction of general industrial complex. This study was processed as following procedures. First, this study drew the trend in the change of the local society of H-gun through collecting literatures and analyzing it. Second, this study proposed a proper level of settlement environments required to the development of surroundings in such industrial complex based on the survey of the consciousness of residents using a statistical method. Finally, this study proposed a development guide for the surroundings based on the proposed level of settlement environments.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.2
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• pp.181-194
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• 2015

Spatial-temporal meteorological features of the Ulsan metropolitan region (UMR) were analyzed using observations and high-resolution numerical modeling. Long-term trend analysis (1970~2013) showed a significant increase of $0.033^{\circ}Cyr^{-1}$ in the 5-year moving average temperature, although detailed short-term features varied, whereas wind speed and relative humidity over the same period displayed clear decreases of $-0.007ms^{-1}$ and $-0.29%yr^{-1}$, respectively. These trends indicate the effects of regional climate change and urbanization in the UMR. Seasonal variations averaged for the most recent three years, 2011~2013, showed that temperatures in three different regions (urban/industrial, suburban, coastal areas) of the UMR had similar seasonality, but significant differences among them were observed for a certain season. Urban and industrial complex regions were characterized by relatively higher temperatures with large differences (max.: $3.6^{\circ}C$) from that in the coastal area in summer. For wind speed, strong values in the range from 3.3 to $3.9ms^{-1}$ occurred in the coastal areas, with large differences clearly shown between the three regions in September and October. Diurnal variations of temperature were characterized by pronounced differences during the daytime (in summer) or nighttime (in winter) between the three regions. Results from the WRF modeling performed for four months of 2012 showed large variations in gridaverage temperature and winds in the UMR, which displayed significant changes by season. Especially, a clear temperature rise in the urban center was identified in July ($0.6^{\circ}C$ higher than nearby urban areas), and overall, relatively weak winds were simulated over urban and inland suburban regions in all seasons.

• Journal of Korea Society of Industrial Information Systems
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• v.18 no.2
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• pp.19-25
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• 2013

In this paper, we propose an approach to tracking road regions from video sequences. The proposed method segments and tracks road regions by utilizing the prior information from the result of the previous frame. For the efficiency of the system, we have a simple assumption that the road region is usually shown in the lower part of input images so that lower 60% of input images is set to the region of interest(ROI). After initial segmentation using flood-fill algorithm, we merge neighboring regions based on color similarity measure. The previous segmentation result, in which seed points for the successive frame are extracted, is used as prior information to segment the current frame. The similarity between the road region of the previous frame and that of the current frame is measured by the modified Jaccard coefficient. According to the similarity we refine and track the detected road regions. The experimental results reveal that the proposed method is effective to segment and track road regions in noisy and non-noisy environments.

• Journal of the Economic Geographical Society of Korea
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• v.20 no.1
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• pp.34-48
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• 2017

The purpose of this study is to investigate the growth of major industries and effects of regional employment on the economic growth of Goyang city and Seongnam city in Gyeonggi Province. We examine the structural changes of the industrial specialization and factors of the growth in two regions by applying Location Quotients and dynamic shift-share analysis respectively. Both regions have been strengthened gradually in their industrial bases during the last 20 years since they have developed as the bed-towns for Seoul with the First Newtown Project of the Metropolitan Seoul area. These two regions have secured in the industrial specialization and competitiveness compare to other regions in the Metropolitan Seoul area. In particular, knowledge service industries have been agglomerated in both regions. Goyang city have secured in the medical welfare, culture and tourism of service sectors, while Seongnam city have secured in the information service and science technology service sectors. Therefore, each region might be differentiated regional foster industries in these sectors in order to succeed the economic development.

• Journal of Soil and Groundwater Environment
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• v.21 no.3
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• pp.49-57
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• 2016

This study investigated the 16 priority PAH concentrations and emission sources from two region (Southwest and East) soils in Jeollanamdo. National industrial complexes have been operated in these regions. PAH concentrations in east region were higher than southeast region, and 9.1 times higher for polluted area and approximately 8.5 times higher for industrial complex were observed. Individual PAH ratios and LMW/HMW ratio indicated that PAHs were emitted from pyrogenic sources in two regions. Average Ant/(Ant+Phe) ratios in southwest and east were 0.14 and 0.22, respectively. From a principal component analysis, it was concluded that PAHs were originated from vehicles and coal power plants.

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1403-1415
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• 2011

To understand the transport of anchovy egg-larvae, an integrated model consisting of a hydrodynamic model and a three-dimensional Lagrangian diffusion model was used for the anchovy Engraulis japornicus egg-larvae trace. Fist, in order to determine the circulation characteristics of the South Sea of Korea, residual flow according to tide, density and wind effect was investigated. In offshore regions, tide-induced residual current tends to flow eastward during the spring tide and westward during the neap tide. Residual flow is irregular due to the bottom topography in the coastal area. No special tendency was apparent in the open sea. Especially, the flow in the offshore regions showed results similar to that of the Tsushima Warm Current. The transport of anchovy egg-larvae is decided the physical properties of sea water. It is estimated that anchovy eggs spawned near the Jeju Island travels offshore, rather than to coastal areas, and grow in the front area between the coastal sea and offshore regions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.2021-2025
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• 2009

This study was to investigate the phytoplankton communities and phytohydrographic characteristics of the inside and outside of the Saemangeum Reservoir from May to November 2006 directly after dike construction. As the cluster analyses, phytohydrographic regions were devided into fresh river water and seawater regions, and the similarities between the sampling sites fluctuated temporarily. Distinctive phytohydrographic difference was shown between inside and outside of the dike in summer. After the dike construction, declining salinity and changing water quality have caused to change the phytoplankton communities and phytohygrographic regions.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.5
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• pp.197-207
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• 2009

The career orientations of an individual are affected by his/her career anchors that are comprised of needs, values, and capabilities. This study is intended to understand the career orientations by way of discovering the career anchors that are possessed by IT workforce in Daegu-Gyeongbuk regions. In particular, such demographic factors as gender, age, job tenure, and job title were investigated to see if these factors in fact affected the career anchors of IT workforce. To achieve this purpose, we collected questionnaires from 269 IT workers in the regions. The results of this study is expected to contribute to our understanding of the career orientations of IT workforce in the region.