• Title/Summary/Keyword: 정 모델

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The Estimation of Succession Index by Community Types in the Natural Deciduous Forest of Mt. Jumbong (점봉산 일대 천연활엽수림의 군집 유형별 천이지수 추정)

  • Jin, Guang Ze;Kim, Ji Hong
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.723-728
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    • 2006
  • Since the forest succession is changing process in the structure and function of a forest for the long period of time, the objectivity of the process could be improved through the development of model or statistical methodology. This study was carried out to estimate succession index based on climax index and species composition parameters, thereupon to compare the succession index with life form and species diversity so as to grasp the information of quantitative successional process for the six community types in the natural deciduous forest of Mt. Jumbong area. The results indicated that Quercus mongolica-Tilia amurensis community had the greatest succession index of 67.5, followed by Abies holophylla-Fraxinus mandshurica community with 67.4. Juglans mandshurica-Cornus controversa community was recorded the smallest value of 60.5. The succession index of overstory tended to increase considerably at the stage of steady state for all community types except Quercus mongolica-Tilia amurensis community. However, The index of midstory hardly varied as the forest succession would progress for all community types. The succession index was negatively correlated to wind-water dispersion type of life form and positively to animal dispersion type at the 5% probability level. On the other hand, the index was not significantly correlated to the species richness and Shannon's species diversity index.

Implementation of a Data Processing Method to Enhance the Quality and Support the What-If Analysis for Traffic History Data (교통이력 데이터의 품질 개선과 What-If 분석을 위한 자료처리 기법의 구현)

  • Lee, Min-Soo;Cheong, Su-Jeong;Choi, Ok-Ju;Meang, Bo-Yeon
    • The KIPS Transactions:PartD
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    • v.17D no.2
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    • pp.87-102
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    • 2010
  • A vast amount of traffic data is produced every day from detection devices but this data includes a considerable amount of errors and missing values. Moreover, this information is periodically deleted before it could be used as important analysis information. Therefore, this paper discusses the implementation of an integrated traffic history database system that continuously stores the traffic data as a multidimensional model and increases the validity and completeness of the data via a flow of processing steps, and provides a what-if analysis function. The implemented system provides various techniques to correct errors and missing data patterns, and a what-if analysis function that enables the analysis of results under various conditions by allowing the flexible definition of various process related environment variables and combinations of the processing flows. Such what-if analysis functions dramatically increase the usability of traffic data but are not provided by other traffic data systems. Experimantal results for cleaning the traffic history data showed that it provides superior performance in terms of validity and completeness.

A Comparison Study of Direct Impact Analysis of Vehicle to Concrete Pier and In-Direct Impact Analysis using Load-Time History Functions (차량과 콘크리트 교각의 직접충돌해석법과 충돌하중이력곡선을 이용한 간접충돌해석법 비교연구)

  • Kim, WooSeok;Kim, Kyeongjin;Lee, Jaeha
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.27 no.6
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    • pp.533-542
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    • 2014
  • In design standards such as AASHTO LRFD and Korea Highway Bridge Design, the dynamic behaviors under the impact loading has not been considered and it recommends of using a static force for designing bridge column against vehicle collisions. Accordingly, in this study, models of vehicle collisions to concrete bridge column were developed with various boundary conditions in order to take into account dynamic behaviour of the column. Cargo trucks of 10tons, 16tons and 38tons were selected and a typical type of concrete bridge pier column along the Kyungbu highway in Korea was selected for this study. Results from this study indicate that the static load specified in the design standards are too small compared to results obtained in this study. It was also found that a consideration of the bridge superstructure allowed smaller damages of concrete bridge pier column under truck impact loadings. Furthermore, a comparison study of direct impact analysis of vehicle to bridge-column with in-direct impact analysis using load-time history functions was performed. The in-direct impact analysis shows that the use of load-time history graph improves the computational cost up to 92% and predict the behaviors of the bridge column under the impact loadings well. The obtained load-time history graph could be easily applied to several existing models.

Seismic Traveltime Tomography in Inhomogeneous Tilted Transversely Isotropic Media (불균질 횡등방성 매질에서의 탄성파 주시토모그래피)

  • Jeong, Chang-Ho;Suh, Jung-Hee
    • Geophysics and Geophysical Exploration
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    • v.10 no.4
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    • pp.229-240
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    • 2007
  • In this study, seismic anisotropic tomography algorithm was developed for imaging the seismic velocity anisotropy of the subsurface. This algorithm includes several inversion schemes in order to make the inversion process stable and robust. First of all, the set of the inversion parameters is limited to one slowness, two ratios of slowness and one direction of the anisotropy symmetric axis. The ranges of the inversion parameters are localized by the pseudobeta transform to obtain the reasonable inversion results and the inversion constraints are controlled efficiently by ACB(Active Constraint Balancing) method. Especially, the inversion using the Fresnel volume is applied to the anisotropic tomography and it can make the anisotropic tomography more stable than ray tomography as it widens the propagation angle coverage. The algorithm of anisotropic tomography is verified through the numerical experiments. And, it is applied to the real field data measured at limestone region and the results are discussed with the drill log and geological survey data. The anisotropic tomography algorithm will be able to provide the useful tool to evaluate and understand the geological structure of the subsurface more reasonably with the anisotropic characteristics.

SpatioTemporal GIS를 활용한 도시공간모형 적용에 관한 연구 / 인구분포모델링을 중심으로

  • 남광우;이성호;김영섭;최철옹
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2002.03b
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    • pp.127-141
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    • 2002
  • GIS환경에서 도시모형(urban model)의 적용을 목적으로 사회·경제적 데이터(socio-economic data)를 활용하는 과정은 도시현상이 갖는 복잡성과 변동성으로 인해 하나의 특정시간에서의 상황을 그대로 저장한 형태인 스냅샷 모형(snapshot model)만으로는 효율적인 공간분석의 실행이 불가능하다. 또한 도시모형을 적용하는 과정에서 GIS의 대상이 되는 공간, 속성, 시간의 정의는 분석목적에 따라 다르게 정의되어질 수 있으며 이에 따라 상이한 결과가 도출될 수 있다. 본 연구는 30년 간의 부산시 인구분포의 동적 변화과정 관측을 위해 시간개념을 결합한 Temporal GIS를 구축하고 이를 활용하여 인구밀도모형 및 접근성모형을 적용하는 과정을 통해 보다 효율적이고 다양한 결과를 제시할 수 있는 GIS 활용방안을 제시하고자 하였다. 흔히 공간현상의 계량화와 통계적 기법의 적용을 위한 데이터 처리과정은 많은 오차와 오류를 유발할 수 있다. 이러한 문제의 해결을 위해서는 우선적으로 분석목적에 맞는 데이터의 정의(Data Definition), 적용하고자 하는 모형(Model)의 유용성 검증, 적절한 분석단위의 설정, 결과해석의 객관적 접근 등이 요구된다. 이와 더불어 변동성 파악을 위한 시계열 자료의 효율적 처리를 위한 방법론이 마련되어져야 한다. 즉, GIS환경에서의 도시모형의 적용에 따른 효율성과 효과성의 극대화를 위해서는 분석목적에 맞는 데이터모델의 설정과 공간DB의 구축방법이 이루어져야 하며 분석가능한 데이터의 유형에 대한 충분한 고려와 적용과정에서 분석결과에 중대한 영향을 미칠 수 있는 요소들을 미리 검증하여 결정하는 순환적 의사결정과정이 필요하다., 표준패턴을 음표와 비음표의 두개의 그룹으로 나누어 인식함으로써 DP 매칭의 처리 속도를 개선시켰고, 국소적인 변형이 있는 패턴과 특징의 수가 다른 패턴의 경우에도 좋은 인식률을 얻었다.r interferon alfa concentrated solution can be established according to the monograph of EP suggesting the revision of Minimum requirements for biological productss of e-procurement, e-placement, e-payment are also investigated.. monocytogenes, E. coli 및 S. enteritidis에 대한 키토산의 최소저해농도는 각각 0.1461 mg/mL, 0.2419 mg/mL, 0.0980 mg/mL 및 0.0490 mg/mL로 측정되었다. 또한 2%(v/v) 초산 자체의 최소저해농도를 측정한 결과, B. cereus, L. mosocytogenes, E. eoli에 대해서는 control과 비교시 유의적인 항균효과는 나타나지 않았다. 반면에 S. enteritidis의 경우는 배양시간 4시간까지는 항균활성을 나타내었지만, 8시간 이후부터는 S. enteritidis의 성장이 control 보다 높아져 배양시간 20시간에서는 control 보다 약 2배 이상 균주의 성장을 촉진시켰다.차에 따른 개별화 학습을 가능하게 할 뿐만 아니라 능동적인 참여를 유도하여 학습효율을 높일 수 있을 것으로 기대된다.향은 패션마케팅의 정의와 적용범위를 축소시킬 수 있는 위험을 내재한 것으로 보여진다. 그런가 하면, 많이 다루어진 주제라

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600MW(e) CANDU PHTS Flow Instability and Interconnect Effect

  • Won Jae Lee;Jin Soo Kim;Goon Cherl Park
    • Nuclear Engineering and Technology
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    • v.17 no.4
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    • pp.290-301
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    • 1985
  • 600MW(e) CANDU Primary Heat Transport System (PHTS) is composed of the two “figure-of-eight” loops and is designed to operate with the 4% Reactor Outlet Header (ROH) quality at its rated power. This existence of the two compressible regions and the positive flow-qualitly-void feedbacks are the sources of the PHTS flow instability. To ensure the PHTS stability, ROH-ROH interconnect pipes are installed as passive systems. This paper describes the investigation of the PHTS flow instability at its design full power condition. Also studied are the interconnect effect and the inherent system damping effect on the system stability. The time domain stability analyses are accessed by using the ATHER/MOD-I code which is the improved version of the KAERI developed ATHER code. Under the most adverse system modelling, the “figure-of-eight” symmetric loop shows divergent flow oscillations. Under with the interconnect, the PHTS stability is remarkably enhanced so that the system becomes stable. However, even under the conservative pressurizer modelling, the PHTS shows the more convergent flow oscillations. With the interconnect and the pressurizer modelling, its stability is highly credited. Conclusively, the inherent system damping by pressurizer itself can credit the PHTS stability without the interconnect.

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Neuroprotective Effects of Herbal Ethanol Extract from Gynostemma pentaphyllum on Dopamine Neurons in Rotenone- and MPTP-induced Animal Model of Parkinson's Disease (Rotenone- 및 MPTP-유도 파킨슨병 동물 모델에서 돌외 에탄올 추출물의 Dopamine 신경세포 보호작용)

  • Suh, Kwang Hoon;Choi, Hyun Sook;Shin, Kun Seong;Zhao, Ting Ting;Kim, Seung Hwan;Hwang, Bang Yeon;Lee, Chong Kil;Lee, Myung Koo
    • YAKHAK HOEJI
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    • v.57 no.2
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    • pp.77-86
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    • 2013
  • The neuroprotective effects of herbal ethanol extract (GP-EX) from Gynostemma pentaphyllum on dopamine neurons in animal model of Parkinson's disease (PD) were investigated. Rats and mice were administered with rotenone (2.5 mg/kg) for 28 days and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg) for 5 days for the PD models, respectively and the animals were simultaneously treated with GP-EX (30 mg/kg, daily). After preparing the PD models, the animals were also administered with L-DOPA (10 mg/kg) for 14 days with or without GP-EX treatment. Treatment with GP-EX (30 mg/kg) inhibited the rotenone- and MPTP-induced neurotoxic effects in dopamine neurons of rats or mice, which was determined by the numbers of tyrosine hydroxylase-immunohistochemical staining survival cells, as well as the levels of dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid. GP-EX (30 mg/kg) also showed the protective effects on neurotoxicity which was induced by long-term administration of L-DOPA (10 mg/kg) in rotenone- and MPTP-induced animal model of PD. The used doses of GP-EX (30 mg/kg) did not produce any signs of toxicity, such as weight loss, diarrhea, or vomiting, in rats and mice during the treatment periods. These results suggest that GP-EX has the protective functions against chronic L-DOPA-induced neurotoxic reactions in dopamine neurons of rotenone- and MPTP-induced animal model of PD. Therefore, the natural GP-EX may be beneficial in the prevention of PD progress and L-DOPA-induced neurotoxicity in PD patients.

The Effect of Intravenous Injection of the Water Extract of Angelica gigas Nakai on Gliosis in the Middle Cerebral Artery Occlusion Rats (당귀 추출물 정맥 주사가 Middle Cerebral Artery Occlusion 모델 흰쥐에서 Gliosis 억제에 미치는 영향)

  • Song, Bong-Keun;Jeon, Yong-Cheol;Kim, Sun-Ae;Shim, An-Na;Seong, Kee-Moon;Lee, Eon-Jeon
    • Journal of Pharmacopuncture
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    • v.14 no.3
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    • pp.5-17
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    • 2011
  • Objectives : Gliosis becomes physical and mechanical barrier to axonal regeneration. Reactive gliosis induced by middle cerebral artery occlusion is involved with up-regulation of CD81 and GFAP (Glial fibrillary acidic protein). The current study is to examine the effect of the Angelica gigas Nakai(intravenous injection. 100 mg/kg twice in a day) on CD81 and GFAP of the rat in the brain after middle cerebral artery occlusion. Methods : Cerebral infarction was induced by middle cerebral artery occlusion. And after intravenous injection of water extract of Angelica gigas Nakai, the size of cerebral infarction was measured. Examination of optical microscope were also used to detect the expression of CD81 and GFAP in the brain of the rat. Results : The following results were obtained : We found that size of cerebral infarcion induced by MCAO (Middle Cerebral Artery Occlusion) in rats were decreased after intravenous injection of Angelica gigas Nakai. We injected the extract of Angelica gigas Nakai to the MCAO in rats, and the optical microscope study showed that Angelica gigas Nakai had effect on protecting the cells of hippocampus. We found that GFAP, CD81 and ERK of the brain in rats with cerebral infarction after MCAO were meaningfully decreased after intravenous injecting Angelica gigas Nakai. We found that c-Fos expression of the brain in rats with cerebral infarction after MCAO were significantly increased after intravenous injecting Angelica gigas Nakai. Conclusions : These results indicate that Angelica gigas Nakai could suppress the reactive gliosis, which disturbs the astrocyte regeneration in the brain of the rat with cerebral infarction after MCAO by controlling the expression of CD81 and GFAP. And the effect may be modulated by the up-regulation of c-Fos and ERK.

A Study on the Influence of Apartment Brand Image on Occupancy Satisfaction (아파트 브랜드 이미지가 입주만족도에 미치는 영향 분석)

  • Kim, Dong-Il;Kang, Hee-Sam
    • Journal of the Korea Convergence Society
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    • v.9 no.3
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    • pp.241-247
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    • 2018
  • The purpose of this study is to investigate the relationship between the residential satisfaction and the residential satisfaction in the residential environment. For this study, we analyzed the main factors of occupancy satisfaction by integrating previous studies on brand and housing and purchase intention, developing a research model based on the theoretical study on occupancy satisfaction, and establishing a research hypothesis. The results of this study are as follows: First, the relationship between first brand image and occupancy satisfaction is statistically significant. Second, the relationship between residential satisfaction and residential satisfaction is significant. In addition, the relationship with prices acting as parameters is analyzed to be somewhat significant. Therefore, this study is expected to provide not only useful information in the relationship between apartment supplier and consumer, but also provide basic information on similar research. Therefore, this study is expected to provide not only useful information in the relationship between apartment supplier and consumer, but also provide basic information on similar research. However, due to limitations such as selection of control variables and analytical errors, future research should be conducted through development of more comprehensive and valid indicators.

Wall Shear Stress Distribution in the Abdominal Aortic Bifurcation : Influence of wall Motion, Impedance Phase Angle, and non-Newtonian fluid (복부대동맥 분기관에서의 벽면전단응력 분포 벽면운동과 임피던스 페이즈 앵글과 비뉴턴유체의 영향)

  • Choi J.H.;Kim C.J.;Lee C.S.
    • Journal of Biomedical Engineering Research
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    • v.21 no.3 s.61
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    • pp.261-271
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    • 2000
  • The present study investigated flow dynamics of a two-dimensional abdominal aortic bifurcation model under sinusoidal flow conditions considering wall motion. impedance phase angle(time delay between pressure and flow waveforms), and non-Newtonian fluid using computational fluid dynamics. The wall shear stress showed large variations in the bifurcated region and the wall motion reduced amplitude of wall shear stress significantly. As the impedance phase angle was changed to more negative values, the mean wall shear stress (time-averaged) decreased while the amplitude (oscillatory) of wall shear stress increased. At the curvature site on the outer wall where the mean wall shear stress approached zero. influence of the phase angle was relatively large. The mean wall shear stress decreased by $50\%$ in the $-90^{\circ}$ phase angle (flow wave advanced pressure wave by a quarter period) compared to the $0^{\circ}$ phase angle while the amplitude of wall shear stress increased by $15\%$. Therefore, hypertensive patients who tend to have large negative phase angles become more vulnerable to atherosclerosis according to the low and oscillatory shear stress theory because of the reduced mean and the increased oscillatory wall shear stresses. Non-Newtonian characteristics of fluid substantially increased the mean wall shear stress resulting in a less vulnerable state to atherosclerosis.

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