• 대한원격탐사학회지
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• 제15권3호
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• pp.277-288
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• 1999

본 소고의 목적은 광범위한 시.공간적인 규모에서 일어나는 해양환경의 변화를 관측하기 위한 원격탐사기술의 활용을 전망하는 것이다. 현재 적용되고 있는 해양원격탐사의 기술과 발전 방향을 고찰하여 바람직한 해양원격탐사의 활용방안을 제시하였다. 해양원격탐사의 효율적인 활용을 위해서는 현안문제 해결과 수요자 위주의 관점에서 종합적 계획을 세워 추진하는 것이 바람직하다. 해양환경변화는 그 변화과정이 가지는 시간적 또는 공간적 규모에 맞추어 관측이 되어야 한다. 해양과 연안해역의 다양한 환경변화를 적절히 관측하고, 모니터링 하기 위해서는 이용 가능한 센서의 활용을 확대하여야 한다. 또한, 조사목적에 적합한 관측주기와 관측범위를 다양화하기 위하여 탑재대 (platform)의 종류도 다양화되어야 할 것이다. 현장관측치에 의한 보정과 검증과정은 해양원격탐사 자료의 바른 해석을 위해 반드시 요구되는 단계로 부이 시스템이나 기회성 선박을 적극 활용하는 종합관측망의 일부로 개발되어야 한다.

• 국토계획
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• 제54권6호
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• pp.68-79
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• 2019

The purpose of this study is to propose a transit accessibility analysis method based on temporal variability of travel time. In this study, transit accessibility was defined in three levels (in transit route, spot and region unit) to present findings from different spatial scopes. Recently, Jeju special self-governing province reorganized bus system of the island. To compare transit accessibility before and after transit policy implementation, the reorganized bus system of Jeju special self-governing province was selected as a case study. This study used General Transit Feed Specification (GTFS) data format as storage public transit information, and calculated travel time using ArcGIS GTFS networks analysis tools. In the analysis of individual transit route level, we found the 3 types of accessibility changes which is increments, no significant changes and reductions and these results come from transit route change (number of transfer, distance change) rather than changes of vehicle interval. We found increases of inflow and outflow speed in most target spots and overall transit accessibility has been substantially improved in Jeju island. This study implies that accounting for temporal variability of travel time in accessibility analysis can result in more useful and sophisticated accessibility information in decision-making processes.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.113-116
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• 2004

In this study, the causes of temporal bright image sticking problem in an AC PDP were investigated. The temporal bright image sticking problem in an ac PDP is observed to be a relatively lower luminance following several minutes on-time at a high gray level compared to that of the ordinary turned-on image area. We focused on the detailed causes of image sticking, which are directly related with the visible emission such as the changes in the characteristics of phosphor, MgO surface and gas dynamics. The experimental results show that the thermal quenching of phosphor and temperature-dependent discharge characteristics change cause the image sticking problem.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.515-517
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• 2004

Although sustainable development of a city should in theory be based on updated spatial information like land cover/use changes, in practice there are no effective tools to get such information. However the development of satellite and sensor technologies has increased the supply of high resolution satellite data, allowing cost-effective, multi-temporal monitoring. Especially KOMPSAT-1(KOrea Multi-Purpose SATellite) acquired a large number of images of the whole Korean peninsula and covering some large cities a number of times. In this study land-use patterns and trends of Daejeon from the year 2000 to the year 2003 will be considered using land use maps which are generated by manual interpretation of multi-temporal KOMPSAT EOC imagery and to show the possibility of using high resolution satellite remote sensing data for urban analysis.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권6호
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• pp.2217-2229
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• 2015

Since the variations of illumination, the irregular changes of human shapes, and the partial occlusions, multiple person tracking is a challenging work in computer vision. In this paper, we propose a graph clustering method based on spatio-temporal information of moving objects for multiple person tracking. First, the part-based model is utilized to localize individual foreground regions in each frame. Then, we heuristically leverage the spatio-temporal constraints to generate a set of reliable tracklets. Finally, the graph shift method is applied to handle tracklet association problem and consequently generate the completed trajectory for individual object. The extensive comparison experiments demonstrate the superiority of the proposed method.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.282-285
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• 2006

This study is to present the method for estimating groundwater recharge with temporal-spatial variability using the SWAT model which can represent the heterogeneity of the watershed. The SWAT model can simulate daily surface runoff, evapotranspiration, soil storage, recharge, and groundwater flow within the watershed. The model was applied to Musimcheon watershed located in the upstream of Mihocheon watershed. Hydrological components were determined for the period 2001 - 2004, and the validity of the results was tested by comparing the estimated runoff with the observed runoff data at the outlet of the catchment. The results of temporal and spatial variations of recharge were presented, This study suggests that variations in recharge can be significantly affected by subbasin slope as well as land use changes.

• 한국컴퓨터산업학회논문지
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• 제2권4호
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• pp.507-520
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• 2001

압축된 동영상에서 인덱싱을 위한 장면전환 검출기법에서 기존의 방법들은 순차검색, 비순차검색, 모션벡터 등을 이용한다. 본 논문에서는 동영상의 장면전환 검출 속도 및 성능을 개선하기 위해 비순차적 검색 방법을 이용한 Hybrid 기법을 제안하였다. 비순차적 검색방법만으로는 영상의 급격한 변화에는 좋은 결과를 보이지만 점진적으로 변화하는 구간에서는 검출성능이 우수하지 못한 문제가 있다. 이러한 문제를 해결하기 위해 본 논문에서는 급진적인 장면전환검색에는 이진검색기법을 사용하고 점진적인 장면전환검색에서는 분산을 이용하는 Hybrid 알고리즘을 제안하여 검색속도 및 검색성능을 개선하였다. 검색속도는 기존의 순차검색 방법에 비해 10배정도 향상되었다.

• 대한치과교정학회지
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• 제11권2호
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• pp.161-168
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• 1981

This study was undertaken to observe the histologic changes of surrounding maxillary sutures to the widening of midpalatal suture, using two adult dogs, weighing about 10 kg, for experimental, and one for control group. After widening of the midpalatal suture with expansion screw for ten days was performed, and followed by sacrifice of experimental animals. Tissues were excised from 5 surrounding maxillary suture portions such as, internasal, interfrontal, midsagittal, zygomatrco-temporal, and midpalatal sutures. After that, the specimens were fixed and decalcified in $10\%$ formalin sol. and $5\%$ nitric acid. Embedding in paraffin and serial sections at a thickness of 5 micron was done, After Hematoxylin-Eosin staining and light microscopic examination, Following results were obtained: 1. In midpalatal suture area, which showed most prominent histologic change, High degree of fibronlastic and osteoblastic proliferation lining the bony trabeculae with osteoid tissue projection into the fibrous connective tissue were observed. 2. In interfrontal suture area, moderate degree of fibroblastic and osteoblastic proliferation was observed. 3. In internasal suture area, active osteoblastic and osteoclastic proliferation lining the bony trabeculae was observed, and separation of fibrous connective tissue was also observed. 4. In midsagittal and zygomatico-temporal suture areas, no histologic changes can be observed.

• The Korean Journal of Ecology
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• 제20권4호
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• pp.275-283
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• 1997

Vertical and temporal characteristics of desalinized reclaimed soil were analyzed from reclaimed coastal land on the western coast of Korea. Of the vertical changes during desalting, pH valuse were the lowest at the topsoil without regard to reclaimation time. The content of C1 were designated as the early period (the first 2-4 years) which decreased exponentially and the later period(the last 5-7 years) which was almost constant, from top to down. In temporal changes of the soil attributes, pH values increased for 5 years and decreased at 6 year after reclamation. Chlorine leaches more rapidly than Na does, K and Ca are constant but Mg increases as time elapsed after reclamation. Sometimes the content of Ca and K in the reclaimed soil are of higher concentration than that of the seawater after reclamation. During desallinization as exemplified by decreasing EC of the soil, Cl and Na are rapidly leached, but K, Ca and Mg are somewhat enhanced. The ration of Na/Cl in the soil equals 1 when the EC registers 5 mmho and then increases dramatically as the EC decreases. Rapid leaching of $Cl^{-}$ elicits an increasing pH valus. The electrostatic balance of the soil is achived by replacement of $Cl^{-}$ with $OH^{-}$ until stationary or until a decreasing pH value is reached again.

• Toxicological Research
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• 제24권2호
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• pp.113-117
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• 2008

Chronic exposure to ethanol induces cumulative damage to the liver starting from fatty infiltration to cirrhosis depending on the dose and duration of exposure. The whole process leading to the development of alcoholic liver disease is very complex and the mechanisms involved are not fully understood. Among many experimental animal models, Lieber-DeCarli liquid diet provides moderate to severe pathophysiological outcome depending on the compositional changes. In the present study, we investigated the temporal changes in the early phase hepatic disease in rats fed with standard Lieber-DeCarli diet. Male Wistar rats were fed with Lieber-Decarli ethanol diet for 6 weeks and the liver samples were obtained after 2, 4 and 6 weeks. Mild fatty infiltration was observed in 2 weeks of feeding and it became evident in 4 and 6 week samples. The level of hepatic triglyceride showed a good agreement with the data obtained in the pathological analysis. Feeding mice with ethanol diet resulted in the maturation and translocation of SREBP-1 to nucleus in the liver. Western blot analysis of the pooled liver sample of control and ethanol fed animals showed a clear-cut time-dependent increase in the expression of nSREBP-1. These data provide important information for selecting proper time point in experimental intervention study in the field of drug development for alcoholic liver disease.