• 제목/요약/키워드: Temporal changes

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Intracellular Localization and Developmental Changes of Purine Catabolic Enzymes during Germination in Cotyledons of Rape Seedlings (발아중 유채자엽 퓨린 분해효소의 활성변화 및 세포내 위치)

  • 권덕기
    • Journal of Plant Biology
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    • v.28 no.3
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    • pp.225-232
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    • 1985
  • Intracellular localization and the developmental changes in activities of uricase and allantoinase during germination were investigated with the cotyledons of rape(Brassica napus L.) seedlings. The development anddisappearance of uricase activity took place independently of light, but allantoinase activity was increased by light. The temporal pattern of uricase activity showed that uricolysis was actively taking place in the cotyledons during their early stages of germination. While uricase can be localized in the microbody fraction isolated from crude organelle extracts of the cotyledons by density gradient centrifugation, most of the allantoinase activity found in the microbody fraction did not appear to be an integral part of the microbody.

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Application of On-line System for Monitoring and Forecasting Surface Changes for Korean Peninsula

  • Lee, Sang-Hoon
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.268-273
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    • 1998
  • This study applies an on-line system, which employes an adaptive reconstruction technique to monitor and forecast ocean surface changes. The system adaptively generates an appropriate synthetic time series with recovering missing measurements for sequential images. The reconstruction method incorporates temporal variation according to physical properties of targets and anisotropic spatial optical properties into image processing techniques. This adaptive approach allows successive refinement of the structure of objects that are barely detectable in the observed series. The system sequentially collects the estimated results from the adaptive reconstruction and then statistically analyzes them to monitor and forecast the change in surface characteristics.

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Assessment of Hydrological Impact by Tracing Long-term Land Cover Changes Using Landsat TM Imageries

  • Kim, Seong J.;Park, Geun A.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.50-52
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    • 2003
  • The purpose of this study is to evaluate the hydrological impact due to temporal land cover changes by gradual urbanization of a watershed. WMS HEC-1 was adopted, and DEM with 200m resolution and hydrologic soil group from 1:50,000 soil map were prepared. Land covers of 1986, 1990, 1994 and 1999 Landsat TM images were classified by maximum likelihood method. By applying the model, watershed average CN value was affected in the order of paddy, forest and urban/residential, respectively.

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Influences of Oceanographic Features on Spatial and Temporal Distributions of Size Spectrum of Walleye Pollock, Gadus chalcogrammus Inhabiting Middle Eastern Coast of Korea (동해 중부 연안 환경 변화에 따른 명태 개체 크기 및 분포의 시공간적 변화)

  • Jung, Hae Kun;Lee, Chung Il;Park, Hyun Je;Park, Joo Myun
    • Korean Journal of Ichthyology
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    • v.32 no.3
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    • pp.148-159
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    • 2020
  • This study investigated the seasonal and inter-annual changes in vertical distribution and size spectrum of walleye pollock, Gadus chalcogrammus inhabiting middle eastern coast of Korea (hear after pollock). Pollock was distributed between 50 m and 600 m depth range, and body size (total length) ranged from 16.6 cm to 81.5 cm. The trends of population body size were increased in autumn and winter and decreased in spring and summer. Vertical distribution of pollock showned depth-dependent patterns with distributing smaller individuals mainly in the upper layer (shallower depth), while larger fish in deeper habitats. Those patterns in vertical distribution of pollock population is probably due to be the results of energy-saving strategy, metabolic effects, and changes in prey selections according to pollock growth, derived from spatial and temporal changes in oceanic condition in habitat grounds. When water temperature in upper layer were increased and that of below thermocline depth became decreased in 2017, the ratio of smaller (<35 cm) and larger (≥35 cm) individuals was biased toward larger fishes, extending their distribution into shallow depth, and consequently main fishing ground was formed in far from coastal area. In addition, the ratio of smaller individual distributing between 100~300 m was increased with decreasing temperature gradient between below thermocline and bottom layer. Changes in spatial and temporal distributions of pollock population likely be related with vertical and horizontal changes in oceanic conditions and, consequently food supplies.

Topographic Changes of Ictal Hyperperfusion During Progression of Clinical Seizures (간질발작의 진행에 따른 발작기 SPECT의 혈류증가 양상)

  • Shin, Won-Chul;Hong, Seung-Bong;Tae, Woo-Suk;Shon, Young-Min;Seo, Dae-Won;Kim, Byoung-Joon;Hong, Seung-Chyul;Kim, Sang-Eun
    • The Korean Journal of Nuclear Medicine
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    • v.35 no.6
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    • pp.352-363
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    • 2001
  • Purpose: To investigate ictal hyperperfusion patterns during semiologic progression of seizures, we performed SPECT subfraction in 50 patients with temporal lobe epilepsy (TLE). Materials and Methods: The patients were categorized Into five groups according to semiologic progression during ictal SPECT (group-1 having only aura; group-2 haying motionless staling with or without aura; group-3 having motionless staring and then automatism with or without aura; group-4 having motionless staring and then dystonic posturing with or without aura and automatism; group-5 having motionless staring, automatism, then head version and generalized seizures with or without aura and dystonic posturing). Results: In group-1, three patients showed ipsilateral temporal hyperperfusion and two had bilateral temporal hyperperfusion with ipsilateral predominance. In group-2, three (42.9%) patients showed bilateral temporal hyperperfusion with unilateral predominance and four (57.1%) revealed insular hyperperfusion of epileptic side. In group-3, 15 patients (88.2%) showed bilateral temporal hyperperfusion with unilateral predominance and 12 (70.6%) insular hyperperfusion. In group-4, 11 patients (84.6%) showed basal ganglia hyperperfusion on the opposite hemisphere to the side of the dystonic posturing. en group-5, there were multiple hyperperfusion areas in the frontal, temporal and basal ganglia regions. However, the injection times of radiotracer in five groups were relatively short and similar. Conclusions: The semiologic progression in TLE seizures were related to the propagation of hyperperfusion from ipsilateral temporal lobe to contralateral temporal lobe, insula, basal ganglia, and frontal lobe. Not only the radiotracer injection time but also semiologic progression after the Injection was significant in determining hyperperfusion pattern of ictal SPECT.

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A Markov Chain Model for Population Distribution Prediction Considering Spatio-Temporal Characteristics by Migration Factors (이동요인별 시·공간적 인구이동 특성을 고려한 인구분포 예측: 마르코프 연쇄 모형을 활용하여)

  • Park, So Hyun;Lee, Keumsook
    • Journal of the Economic Geographical Society of Korea
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    • v.22 no.3
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    • pp.351-365
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    • 2019
  • This study aims to predict the changes in population distribution in Korea by considering spatio-temporal characteristics of major migration reasons. For the purpose, we analyze the spatio-temporal characteristics of each major migration reason(such as job, family, housing, and education) and estimate the transition probability, respectively. By appling Markov chain model processes with the ChapmanKolmogorov equation based on the transition probability, we predict the changes in the population distribution for the next six years. As the results, we found that there were differences of population changes by regions, while there were geographic movements into metropolitan areas and cities in general. The methodologies and the results presented in this study can be utilized for the provision of customized planning policies. In the long run, it can be used as a basis for planning and enforcing regionally tailored policies that strengthen inflow factors and improve outflow factors based on the trends of population inflow and outflow by region by movement factors as well as identify the patterns of population inflow and outflow in each region and predict future population volatility.

Spatio-temporal Graph for Representing Historical Situations in Virtual Reality (가상현실 속의 상황 표현을 위한 시공간 그래프)

  • Park, Jong-Hee;Cho, Kyu-Myoung
    • The Journal of the Korea Contents Association
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    • v.12 no.8
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    • pp.1-12
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    • 2012
  • We develop the Spatio-Temporal Graph to imbue the historical context to the situations in a virtual world, and an ontology to enable a structural description of their elements such as the objects, relationships, and activities. In the time dimension the graph models all the temporal phases of the future besides the past and present in a comprehensive manner, and all the spatial aspects in an intuitive but efficient fashion. The overall architecture composing the Physical Layer, Logical Layer and Conceptual Layer which are integrated according to their interrelations allows events occurring in their corresponding worlds to be simulated in historical context. The S-T Graph could be used both to simulate the situations in the virtual world and to realize the knowledge systems of the virtual inhabitants to be used in judging and evaluating those situations. By adding temporal changes to the multi-layered architecture of our virtual world, this model lays a foundation for maximizing the diversity of situations in the simulation of a virtual world.

Cache Replacement Policy Based on Dynamic Counter for High Performance Processor (고성능 프로세서를 위한 카운터 기반의 캐시 교체 알고리즘)

  • Jung, Do Young;Lee, Yong Surk
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.4
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    • pp.52-58
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    • 2013
  • Replacement policy is one of the key factors determining the effectiveness of a cache. The LRU replacement policy has remained the standard for caches for many years. However, the traditional LRU has ineffective performance in zero-reuse line intensive workloads, although it performs well in high temporal locality workloads. To address this problem, We propose a new replacement policy; DCR(Dynamic Counter based Replacement) policy. A temporal locality of workload dynamically changes across time and DCR policy is based on the detection of these changing. DCR policy improves cache miss rate over a traditional LRU policy, by as much as 2.7% at maximum and 0.47% at average.

Exploring Spatio-Temporal Variations of Land Price in Daegu Metropolitan City (대구시 지가의 시공간적 변화 탐색)

  • Kim, Kamyoung
    • Journal of the Korean association of regional geographers
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    • v.18 no.4
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    • pp.414-432
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    • 2012
  • Land price is a kind of text to read urban spatial structure. The purpose of this paper is to inquire into the characteristics of Daegu's urban structure and its change in time through exploring spatio-temporal variations of land price with a detailed spatial and temporal resolution. To achieve this, land value surfaces were represented using the officially assessed land price every other year from 1995 to 2011. Through mapping and exploring spatio-temporal patterns and fluctuation rates of land price for this period, changes in urban structure, the effects of local decision makings such as Greenbelt adjustment, housing site development, and gentrification, and the effects of business fluctuations or policies at global or national scales could be caught. In addition, the trends for suburbanization and multi-centric urban form could be examined from the results of a negative exponential model explaining the effect of distance from an urban center on spatial variation of land price. These results demonstrate that urban analysis using land price mirroring spatial decision making at various scales could deepen understanding for internal structure and change of a city and provide useful information for establishing regional and urban development policies and evaluating their effects.

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