• Title/Summary/Keyword: 모델 이해

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Sensitivity Analysis of Satellite BUV Ozone Profile Retrievals on Meteorological Parameter Errors (기상 입력장 오차에 대한 자외선 오존 프로파일 산출 알고리즘 민감도 분석)

  • Shin, Daegeun;Bak, Juseon;Kim, Jae Hwan
    • Korean Journal of Remote Sensing
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    • v.34 no.3
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    • pp.481-494
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    • 2018
  • The accurate radiative transfer model simulation is essential for an accurate ozone profile retrieval using optimal estimation from backscattered ultraviolet (BUV) measurement. The input parameters of the radiative transfer model are the main factors that determine the model accuracy. In particular, meteorological parameters such as temperature and surface pressure have a direct effect on simulating radiation spectrum as a component for calculating ozone absorption cross section and Rayleigh scattering. Hence, a sensitivity of UV ozone profile retrievals to these parameters has been investigated using radiative transfer model. The surface pressure shows an average error within 100 hPa in the daily / monthly climatological data based on the numerical weather prediction model, and the calculated ozone retrieval error is less than 0.2 DU for each layer. On the other hand, the temperature shows an error of 1-7K depending on the observation station and altitude for the same daily / monthly climatological data, and the calculated ozone retrieval error is about 4 DU for each layer. These results can help to understand the obtained vertical ozone information from satellite. In addition, they are expected to be used effectively in selecting the meteorological input data and establishing the system design direction in the process of applying the algorithm to satellite operation.

Development of a gridded crop growth simulation system for the DSSAT model using script languages (스크립트 언어를 사용한 DSSAT 모델 기반 격자형 작물 생육 모의 시스템 개발)

  • Yoo, Byoung Hyun;Kim, Kwang Soo;Ban, Ho-Young
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.3
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    • pp.243-251
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    • 2018
  • The gridded simulation of crop growth, which would be useful for shareholders and policy makers, often requires specialized computation tasks for preparation of weather input data and operation of a given crop model. Here we developed an automated system to allow for crop growth simulation over a region using the DSSAT (Decision Support System for Agrotechnology Transfer) model. The system consists of modules implemented using R and shell script languages. One of the modules has a functionality to create weather input files in a plain text format for each cell. Another module written in R script was developed for GIS data processing and parallel computing. The other module that launches the crop model automatically was implemented using the shell script language. As a case study, the automated system was used to determine the maximum soybean yield for a given set of management options in Illinois state in the US. The AgMERRA dataset, which is reanalysis data for agricultural models, was used to prepare weather input files during 1981 - 2005. It took 7.38 hours to create 1,859 weather input files for one year of soybean growth simulation in Illinois using a single CPU core. In contrast, the processing time decreased considerably, e.g., 35 minutes, when 16 CPU cores were used. The automated system created a map of the maturity group and the planting date that resulted in the maximum yield in a raster data format. Our results indicated that the automated system for the DSSAT model would help spatial assessments of crop yield at a regional scale.

Solitary Hepatic VX2 Tumor Model and Its CT Findings in Rabbits (가토에서 VX2 단일간암모델과 CT 소견)

  • Lee, Hae-Beom;Lee, Ki-Chang
    • Journal of Veterinary Clinics
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    • v.23 no.4
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    • pp.388-392
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    • 2006
  • To verify the solitary nodular hepatocellular tumor model induced by intraparenchymal VX2 tumor cell injection and assess the diagnostic imaging character by computed tomography in rabbits. The tumor cell fragment ($1{\sim}2mm^3$) was loaded in Seldinger needle and directly implanted into the livers of 80 New Zealand white rabbits. The tumor size and patterns of tumor growth were evaluated using spiral computed tomography (CT) at 1, 2, and 3 weeks after tumor implantation. A solitary nodular tumor was successfully created in 82.5% (66/80). The mortality rate was 5% (4/80). The tumor sizes measured were 7.46.3, 14.210.8, 16.212.6 cm at 1, 2, and 3 weeks after tumor implantation on arterial phase CT images. The tumors were round to oval shape with peripheral enhancement and central hypoattenuation on arterial phase, and hypoatteuated wash-out pattern on portal phase. It is considered that inoculation of tumor fragment loaded in Seldinger needle is useful and practical method for creating a solitary hepatic tumor. And CT scanning are valuable to investigate the hepatic tumor and compatible to the observations on macro-and microscopic findings.

A Performance and Change Management Based Method for Developing e-Government Enterprise Architecture (전자정부 엔터프라이즈 아키텍처 도입을 위한 성과 및 변화관리 기반의 개발 방법)

  • Seo, Kyeong-Seog;Ahn, Sang-Im;Chong, Ki-Won
    • The Journal of Society for e-Business Studies
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    • v.11 no.4
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    • pp.1-20
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    • 2006
  • Many government offices have been proceeding a development of Enterprise Architecture(EA) according to apply Government-wide Enterprise Architecture'. Each office and working-level officials have had a hard time because of no guides related to a EA development method such as the Framework, Standards, Principle, Reference Model, Etc. This paper propose a method for developing e-Government Enterprise Architecture considered a characteristic of public institutes through analyzing existing cases. The method for development e-Government EA includes the EA Performance Management Model to monitor objectively each office's long-term business promotion because the e-Government EA development is a job of long duration and cooperation with many institutes. This method also combines the EA Change Management Activities for the officials to improve general knowledge about EA's idea and EA's value, etc. We show the EA case study of the Ministry of Government Administration and Home Affairs to demonstrate feasibility of our approach. As a result, public offices will carry out their BPR(Business Process Re-engineering) and ISP(Information Strategy Planning) more efficiently based on this EA development method.

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A Geomorphological Classification System to Chatacterize Ecological Processes over the Landscape (생태환경 특성 파악을 위한 지형분류기법의 개발)

  • Park Soo-Jin
    • Journal of the Korean Geographical Society
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    • v.39 no.4
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    • pp.495-513
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    • 2004
  • The shape of land surface work as a cradle for various environmental processes and human activities. As spatially distributed process modelings become increasing important in current research communities, a classification system that delineates land surface into characteristic geomorphological units is a pre-requisite for sustainable land use planning and management. Existing classification systems are either morphometric or generic, which have limitations to characterize continuous ecological processes over the landscape. A new classification system was developed to delineate the land surface into different geomorphological units from Digital Elevation Models(DEMs). This model assumes that there are pedo-geomorphological units in which distinct sets of hydrological, pedological, and consequent ecological processes occur. The classification system first divides the whole landsurface into eight soil-landscape units. Possible energy and material nows over the land surface were interpreted using a continuity equation of mass flow along the hillslope, and subsequently implemented in terrain analysis procedures. The developed models were tested at a 12$\textrm{km}^2$ area in Yangpyeong-gun, Kyeongi-do, Korea. The method proposed effectively delineates land surface into distinct pedo-geomorphological units, which identify the geomorphological characteristics over a large area at a low cost. The delineated landscape units mal provide a basic information for natural resource survey and environmental modeling practices.

Understanding the Pattern of Mobile-phone Tasks on the 'Situational Context' : Focused on the ESR(Extend, Synchronize, Replace) Model (모바일폰 사용 영역과 상황 기반의 컨텍스트 정의 및 사용 행위의 구조 분석을 통한 테스크 모델 제안)

  • Cho, Yun-Jin;Lee, Eun-Jong
    • 한국HCI학회:학술대회논문집
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    • 2008.02b
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    • pp.158-164
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    • 2008
  • This study was conducted for raising the considering the dynamical context of mobile phone use environment in the mobile-phone research. For this I identified the characteristic of the mobile phone use. The first characteristic is that the mobile phone is the context sensitive device. Also, it reflects the user's life pattern because it is the very personal device. I defined the context of mobile phone use with the basis on this identification of those characteristics. I referenced the definition, 'situational context', defining the mobile phone use context. Also, I set up the research scope within the user task that is influential from the situational context, I named this kind of task as the 'contextual task'. I developed the Contextual Task Model in this study. I named the model as the 'ESR Model'. The reason that I developed this contextual task model is that this model can help novice designers and designers unfamiliar with an application domain understand the user behavior and user centered design. And also this model can be effective to communicate each other, I identified the user's contextual tasks three kinds of model. First, the Extend Model includes user tasks that related to extending from user physical working space to the virtual level. Second model is Synchronize Model, which includes issues that lesson the blocking when use several functions at a time or sequentially. Third model is Replace Model, which is come from the characteristic of user life pattern to use the mobile phone. Finally, I proposed an application of this model, CIQ. Through the process to make CIQ I proved the effectiveness of this ESR Model.

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Emerging P2P Traffic Analysis and Modeling (P2P 트래픽의 특성 분석과 트래픽 모델링)

  • 주성돈;이채우
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.2B
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    • pp.279-288
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    • 2004
  • Rapidly emerging P2P(Peer to Peer) applications generate very bursty traffic, which gives a lot of burden to network, and the amount of such traffic is increasing rapidly. Thus it is becoming more important to understand the characteristics of such traffic and reflect it when we design and analyze the network. To do that we measured the traffic in a campus network and present flow statistics and traffic models of the measured traffic, and compare them with those of the web traffic. The results indicate that P2P traffic is much burstier than web traffic and as a result it negatively affects network performance. We modeled P2P traffic using self-similar traffic model to predict packet delay and loss occurred in network which are very important to evaluate network performance. We also predict queue length distribution and loss probability in SSQ(Single Sewer Queue). To assess accuracy of traffic model, we compare the SSQ statistics of traffic models with that of the traffic trace. The results show that self-similar traffic models we use can predict P2P traffic behavior in network precisely. It is expected that the traffic models we derived can be used when we design network capacity and predict network performance and QoS of the P2P applications.

In Vitro and In Vivo Effects of Piceatannol and Resveratrol on Glucose Control and TLR4-NF-κB Pathway (피세아테놀과 레스베라트롤의 혈당조절 및 TLR4-NF-κB 경로 조절 작용)

  • Lee, Hee Jae;Lee, Hae-Jeung;Yang, Soo Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.2
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    • pp.267-272
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    • 2017
  • Piceatannol (PIC) is a natural hydroxylated analog of resveratrol (RSV), which is a polyphenol known to extend lifespan by stimulating sirtuins. The aim of this study was to investigate the effects of PIC and RSV on the toll-like receptor 4 (TLR4)-nuclear factor kappa B ($NF-{\kappa}B$) pathway in mouse hepatocytes and an obese/diabetic KK/HlJ mouse model. AML12 mouse hepatocytes in the absence or presence of palmitic acids (PA) were treated with PIC ($50{\mu}M$) or RSV ($50{\mu}M$). Male KK/HlJ mice at 20 weeks of age were divided into three subgroups as follows: 1) obese and diabetic control (KK), 2) KK_PIC, and 3) KK_RSV. PIC and RSV were administered orally at a dose of 10 mg/kg/d for 4 weeks. Four weeks of PIC and RSV treatment did not affect body weight or food intake in KK mice. Serum fasting blood glucose was significantly reduced in KK_PIC, and 2 h oral glucose tolerance test area under the curve was significantly reduced by PIC and RSV treatment in KK mice. PIC tended to improve homeostasis model assessment of the insulin resistance index (HOMA-IR) and HOMA beta-cells in diabetic KK mice. TLR4 and $NF-{\kappa}B$ were down-regulated by PIC and RSV treatments in hepatocytes in the absence or presence of PA. Insulin receptor, AMP-activated protein kinase, peroxisome proliferator-activated receptor gamma, nucleotide oligomerization domain-like receptor family pyrin domain-containing 3, interleukin-1, and $NF-{\kappa}B$ were altered in PIC-treated livers. Collectively, PIC and RSV inhibited the $TLR4-NF-{\kappa}B$ pathway, and PIC seems to be more effective than RSV in the regulation of analyzed targets, which are involved in insulin signaling and inflammation in vivo.

A Study on GIS Implementation and Maintenance Model in Local Governments (지자체 GIS 추진 및 운영모델에 관한 연구)

  • Koh, Kwang-Chul;Kim, Eun-Hyung
    • Journal of Korea Spatial Information System Society
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    • v.4 no.2 s.8
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    • pp.5-22
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    • 2002
  • The considerable budgets for the 2nd-phase NGIS projects are allocated to the projects for developments of the GIS applications. Especially, the 78 local governments are major users of GIS application systems. In spite of GIS necessity in local government, whether a GIS is 'good' or bad, depends on its implementation and operation. How to implement GIS in effective wav and how to measure GIS effect for justifying GIS funding can be major concerns. Because it takes minimum 3-4 years to equal the costs and benefits of GIS, the long-terms implementation strategies for GIS project in local government are required. In order to establish a proper implementation model for the GIS application projects and to promote activities in the projects, this study considers several problems in accordance with the phases of GIS evolution and solutions of these problems. Based an the GIS auditing and consulting experience in local governments, this study constructs a GIS implementation and maintenance model in long and comprehensive perspective. This model can be a key to affective and realistic implementation for the future GIS projects.

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A Study on 3D Printed Tactile mathematics textbook for Visually Impaired Students (시각장애청소년을 위한 3D 프린팅 촉각수학교재 모델 개발 연구 - 함수 지도와 관련하여 -)

  • Lee, Sang-Gu;Park, Kyung-Eun;Ham, Yoon-Mee
    • Communications of Mathematical Education
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    • v.30 no.4
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    • pp.515-530
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    • 2016
  • Recently an extensive study of the mathematicians who have overcome the visually impaired and contribute to the academic in math was published. In the case of Korea, we can find there are mathematicians who have overcome physical disabilities such as cerebral palsy and polio. However there is no example of blind person who majored mathematics to become a mathematic's teacher or professor and have entered any mathematics related professions. This let us to study the reasons that caused difficulties to visually impaired students majoring in mathematics. We also suggest ways that may help blind students to have access to mathematics intuitively. In this study, we propose a tactile mathematics textbooks and teaching manuals utilizing 3D printing which the visually impaired students can touch and feel. We can supply such materials to visually impaired youth, special education teachers and parents in Korea. As a result, visually impaired students will be able to access mathematics easily and can build their confidence in mathematics. We hope that some blind students with mathematical talent do not hesitate to major mathematics and choose career in mathematical professions.