• Title/Summary/Keyword: model change

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A Study on the Analysis of Behavioral Changes of Smart Devices and the Presentation of the Improved Model (스마트 디바이스 행동변화 애플리케이션 분석을 통한 개선모델 제시)

  • Park, In-Hwa;Kim, Hae-Na;Lee, Youngho
    • Journal of Digital Convergence
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    • v.12 no.11
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    • pp.225-232
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    • 2014
  • Supply of a smart device has been made with the development of communication networks and growing desire of people to improve the quality of life, the service industry about it have been made with smart devices. Among them, there are various services that can help people change their behavior to healthy life. But it does not have a large impact on the behavior change of performer because its been developed as a general process. Therefore in this study examine development situation about current behavior change applications through application markets. Development current situation can be separated by process to two patterns. As a result we propose behavioral change model that includes integrated change model that one of the behavior theory model, accomplish the goal process of goal setting theory and habit formation phase for automate the changes. Also, we provide appropriate service according to the model that leads motivation, sustainability of the action and positive behavior change to performer. We can expect in many aspects such as ability and motivation than existing service.

A Study on Change-Points in System Reliability

  • Kwang Mo Jeong
    • Communications for Statistical Applications and Methods
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    • v.1 no.1
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    • pp.10-19
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    • 1994
  • We study the change-point problem in the context of system reliability models. The maximum likelihood estimators are obtained based on the Jelinski and Moranda model. To find the approximate distribution of the change-point estimator, we suggest of parametric bootstrap method in which the estimators are substituted in the assumed model. Through an example we illustrate the proposed method.

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Modeling of Early Age Concretes Using a CSL Model (CSL 모델을 이용한 초기재령 콘크리트 거동 해석)

  • Zi, Goang-Seup;Jung, Jin-Kyu
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.411-414
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    • 2007
  • The confinement-shear lattice(CSL) model for hardened concretes developed by Cusatis is extended for early age concretes. The uniaxial behaviors available in the literature for 3 to 28 days were simulated by the CSL model to identify the change of the model parameters for various ages. The change with respect to the age was interpolated based on the chemomechanics to develop the extended version of CSL model.

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An Analysis of the Impact of Climate Change on the Korean Onion Market

  • BAEK, Ho-Seung;KIM, In-Seck
    • The Journal of Industrial Distribution & Business
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    • v.11 no.3
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    • pp.39-50
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    • 2020
  • Purpose: Agriculture, which is heavily influenced by climate conditions, is one of the industries most affected by climate change. In this respect, various studies on the impact of climate change on the agricultural market have been conducted. Since climate change is a long-term phenomenon for more than a decade, long-term projections of agricultural prices as well as climate variables are needed to properly analyze the impact of climate change on the agricultural market. However, these long-term price projections are often major constraints on studies of climate changes. The purpose of this study is to analyze the impacts of climate changes on the Korean onion market using ex-post analysis approach in order to avoid the difficulties of long-term price projections. Research design, data and methodology: This study develops an annual dynamic partial equilibrium model of Korean onion market. The behavioral equations of the model were estimated by OLS based on the annual data from 1988 to 2018. The modelling system is first simulated to have actual onion market conditions from 2014 to 2018 as a baseline and then compared it to the scenario assuming the climatic conditions under RCP8.5 over the same period. Scenario analyses were simulated by both comparative static and dynamic approach to evaluate the differences between the two approaches. Results: According to the empirical results, if the climate conditions under RCP8.5 were applied from 2014 to 2018, the yield of onion would increase by about 4%, and the price of onion would decrease from 3.7% to 17.4%. In addition, the average price fluctuation rate over the five years under RCP8.5 climate conditions is 56%, which is more volatile than 46% under actual climate conditions. Empirical results also show that the price decreases have been alleviated in dynamic model compared with comparative static model. Conclusions: Empirical results show that climate change is expected to increase onion yields and reduce onion prices. Therefore, the appropriate countermeasures against climate change in Korean onion market should be found in the stabilization of supply and demand for price stabilization rather than technical aspects such as the development of new varieties to increase productivity.

Conceptual Changes on Geocentricism of Middle School Students Using the Phase Model of the Venus (금성 위상변화 모형을 활용한 중학생의 천동설 개념 변화)

  • Kim, Sun-A;Yoon, Ma-Byong;Kim, Hee-Soo
    • Journal of Science Education
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    • v.34 no.1
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    • pp.47-57
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    • 2010
  • The purpose of this study was to investigate how the lesson using the newly developed Phase Change Model of Venus can change ninth graders' geocentrical concept related to the progression of the phase of Venus. In order to know students' concept change of the progression of the phases of Venus, test sheets and a questionnaire regarding solar systems were developed and used pre and post test. The results showed that many students have an astronomical preconception of geocentricism, and some students have an especially poor scientific understanding of the solar system. However, there were significant changes in students' conceptual levels (p<.05) after teaching with the Venus's Phase Change Model. Therefore, teaching with the Phase Change Model of Venus was effective on students' scientific conceptual change from geocentricism to heliocentricism.

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A Prediction of Forest Vegetation based on Land Cover Change in 2090 (토지피복 변화를 반영한 미래의 산림식생 분포 예측에 관한 연구)

  • Lee, Dong-Kun;Kim, Jae-Uk;Park, Chan
    • Journal of Environmental Impact Assessment
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    • v.19 no.2
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    • pp.117-125
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    • 2010
  • Korea's researchers have recently studied the prediction of forest change, but they have not considered landuse/cover change compared to distribution of forest vegetation. The purpose of our study is to predict forest vegetation based on landuse/cover change on the Korean Peninsula in the 2090's. The methods of this study were Multi-layer perceptrom neural network for Landuse/cover (water, urban, barren, wetland, grass, forest, agriculture) change and Multinomial Logit Model for distribution prediction for forest vegetation (Pinus densiflora, Quercus Spp., Alpine Plants, Evergreen Broad-Leaved Plants). The classification accuracy of landuse/cover change on the Korean Peninsula was 71.3%. Urban areas expanded with large cities as the central, but forest and agriculture area contracted by 6%. The distribution model of forest vegetation has 63.6% prediction accuracy. Pinus densiflora and evergreen broad-leaved plants increased but Quercus Spp. and alpine plants decreased from the model. Finally, the results of forest vegetation based on landuse/cover change increased Pinus densiflora to 38.9% and evergreen broad-leaved plants to 70% when it is compared to the current climate. But Quercus Spp. decreased 10.2% and alpine plants disappeared almost completely for most of the Korean Peninsula. These results were difficult to make a distinction between the increase of Pinus densiflora and the decrease of Quercus Spp. because of they both inhabit a similar environment on the Korean Peninsula.

Evaluation of Future Climate Change Impact on Streamflow of Gyeongancheon Watershed Using SLURP Hydrological Model

  • Ahn, So-Ra;Ha, Rim;Lee, Yong-Jun;Park, Geun-Ae;Kim, Seong-Joon
    • Korean Journal of Remote Sensing
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    • v.24 no.1
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    • pp.45-55
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    • 2008
  • The impact on streamflow and groundwater recharge considering future potential climate and land use change was assessed using SLURP (Semi-distributed Land-Use Runoff Process) continuous hydrologic model. The model was calibrated and verified using 4 years (1999-2002) daily observed streamflow data for a $260.4km^2$ which has been continuously urbanized during the past couple of decades. The model was calibrated and validated with the coefficient of determination and Nash-Sutcliffe efficiency ranging from 0.8 to 0.7 and 0.7 to 0.5, respectively. The CCCma CGCM2 data by two SRES (Special Report on Emissions Scenarios) climate change scenarios (A2 and B2) of the IPCC (Intergovemmental Panel on Climate Change) were adopted and the future weather data was downscaled by Delta Change Method using 30 years (1977 - 2006, baseline period) weather data. The future land uses were predicted by CA (Cellular Automata)-Markov technique using the time series land use data of Landsat images. The future land uses showed that the forest and paddy area decreased 10.8 % and 6.2 % respectively while the urban area increased 14.2 %. For the future vegetation cover information, a linear regression between monthly NDVI (Normalized Difference Vegetation Index) from NOAA/AVHRR images and monthly mean temperature using five years (1998 - 2002) data was derived for each land use class. The future highest NDVI value was 0.61 while the current highest NDVI value was 0.52. The model results showed that the future predicted runoff ratio ranged from 46 % to 48 % while the present runoff ratio was 59 %. On the other hand, the impact on runoff ratio by land use change showed about 3 % increase comparing with the present land use condition. The streamflow and groundwater recharge was big decrease in the future.

Estimation of the Heat Budget Parameter in the Atmospheric Boundary Layer considering the Characteristics of Soil Surface (지표면의 특성을 고려한 대기경계층내의 열수지 parameter 추정 -열수지 parameter를 이용한 중규모 순환의 수치예측-)

  • 이화운;정유근
    • Journal of Environmental Science International
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    • v.5 no.6
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    • pp.727-738
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    • 1996
  • An one dimensional atmosphere-canopy-soil interaction model is developed to estimate of the heat budget parameter in the atmospheric boundary layer. The canopy model is composed of the three balance equations of energy, temperature, moisture at ground surface and canopy layer with three independent variables of Tf(foliage temperature), Tg(ground temperature), and qg(ground specific humidity). The model was verilied by comparative study with OSUID(Oregon State University One Dimensional Model) proved in HAPEX-MOBILHY experiment. Also we applied this model in two dimensional land-sea breeze circulation. According to the results of this study, surface characteristics considering canopy acted importantly upon the simulation of meso-scale circulation. The factors which used in the numerical experiment are as follows ; the change for a sort of soil(sand and peat), the change for shielding factor, and the change for a kind of vegetation.

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A MODIFIED PREY-PREDATOR MODEL WITH COUPLED RATES OF CHANGE

  • HAN, HYEJI;KIM, GWANGIL;OH, SEOYOUNG
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.25 no.4
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    • pp.312-326
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    • 2021
  • The prey-predator model is one of the most influential mathematical models in ecology and evolutionary biology. In this study, we considered a modified prey-predator model, which describes the rate of change for each species. The effects of modifications to the classical prey-predator model are investigated here. The conditions required for the existence of the first integral and the stability of the fixed points are studied. In particular, it is shown that the first integral exists only for a subset of the model parameters, and the phase portraits around the fixed points exhibit physically relevant phenomena over a wide range of the parameter space. The results show that adding coupling terms to the classical model widely expands the dynamics with great potential for applicability in real-world phenomena.

Study on Improvement of Frost Occurrence Prediction Accuracy (서리발생 예측 정확도 향상을 위한 방법 연구)

  • Kim, Yongseok;Choi, Wonjun;Shim, Kyo-moon;Hur, Jina;Kang, Mingu;Jo, Sera
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.4
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    • pp.295-305
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    • 2021
  • In this study, we constructed using Random Forest(RF) by selecting the meteorological factors related to the occurrence of frost. As a result, when constructing a classification model for frost occurrence, even if the amount of data set is large, the imbalance in the data set for development of model has been analyzed to have a bad effect on the predictive power of the model. It was found that building a single integrated model by grouping meteorological factors related to frost occurrence by region is more efficient than building each model reflecting high-importance meteorological factors. Based on our results, it is expected that a high-accuracy frost occurrence prediction model will be able to be constructed as further studies meteorological factors for frost prediction.