• Title/Summary/Keyword: change of variables

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Relationship Between Climate Change and Total Factor Productivity (기후변화와 국가별 총요소생산성의 관계)

  • Choi, Young Jun;Park, Hyun Yong
    • Environmental and Resource Economics Review
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    • v.24 no.2
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    • pp.343-363
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    • 2015
  • This study is to analyze the effects of climate change on national total factor productivity. Changes in temperature and rainfalls which are the representative climate variables are used as main factors to measure climate change. Not only average values of the variables but those highest values are used as independent variables in the model, in order to consider the characteristic pattern of recent climate change, the high volatilities. The OLS results are corresponding to previous literature that average temperature has a negative relationship with productivities while average rainfalls have a positive relationship. However, the results of panel analysis contradict the argument of the negative relationship between average temperature and productivities since human beings can adapt the climate change. Therefore adaptation capacity is important to forecast the effects of climate changes on economies.

The Change in Consciousness and Expenditure on Kyung-Jo after IMF Economic Crisis on Cheju Island (경조비에 대한 의식 및 지출 변화 - IMF경제위기 이후 제주지역을 중심으로 -)

  • 김혜연;김미성
    • Journal of the Korean Home Economics Association
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    • v.39 no.1
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    • pp.65-80
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    • 2001
  • This study aimed to investigate the changed consciousness and expenditure on Kyong-Jo after IMF economic crisis and the some factors which have effects on the change. The expenditure on Kyong-Jo included donations and gifts associated with congratulations and condolences. The data were collected through the personal questionnaire on Cheju Island. The sample consisted of 400 married adults whose age were between 20 to 65. The independent variables were some individual characteristics, household related variables, and Kyong-Jo related variables. The dependent variables included the change in consciousness and expenditure on Kyong-Jo. The data were analyzed by methods such as frequencies, means, Multiple Regression and Logistic Regression analysis. Major results were as follows. The respondents perceived that Kyong-Jo is fundamentally a good custom to help each other when some one is in the hard time. Their perception of the expenditure on Kyong-Jo has not been changed even since IMF economic crisis. 70% of the respondents staid that there was little difference of the expenditure on Kyong-Jo before and after IMF economic crisis. This trend is in contrast to the perception and the expenditure of the people who lived in the other residences after IMF economic crisis. The factors which had significant effects on the respondent's consciousness of the expenditure on Kyong-Jo were occupation, whether owns a house or not, household income, and household assets. The change of household expenditure on Kyong-Jo was effected by the respondent's sex, occupation, household income, household assets, and social network. These results suggested that the respondents on Cheju Island more strongly hold the conservative perception to the expenditure on Kyong-Jo rather than the people in other residences.

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The Proxy Variables Selection of Vulnerability Assessment for Agricultural Infrastructure According to Climate Change (논문 - 기후변화에 따른 농업생산기반 재해 취약성 평가를 위한 대리변수 선정)

  • Kim, Sung-Jae;Park, Tae-Yang;Kim, Sung-Min;Kim, Sang-Min
    • KCID journal
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    • v.18 no.2
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    • pp.33-42
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    • 2011
  • Climate change has impacts on not only the average temperature rise but also the intensity and frequency of extreme events such as flood and drought. It is also expected that the damages on agricultural infrastructure will be increased resulting from increased rainfall intensity and frequency caused by climate change. To strengthen the climate change adaptation capacity, it is necessary to identify the vulnerability of a given society's physical infrastructures and to develop appropriate adaptation strategies with infrastructure management because generally facilities related to human settlements are vulnerable to climate changes and establishing an adaptive public infrastructure would reduce the damages and the repair cost. Therefore, development of mitigation strategies for agricultural infrastructure against climatic hazard is very important, but there are few studies on agricultural infrastructure vulnerability assessment and adaptation strategies. The concept of vulnerability, however, is difficult to functionally define due to the fact that vulnerability itself includes many aspects (biological, socioeconomic, etc.) in various sectors. As such, much research on vulnerability has used indicators which are useful for standardization and aggregation. In this study, for the vulnerability assessment for agricultural infrastructure, 3 categories of climate exposure, sensitivity, and adaptation capacity were defined which are composed of 16 sub-categories and 49 proxy variables. Database for each proxy variables was established based on local administrative province. Future studies are required to define the weighting factor and standardization method to calculate the vulnerability indicator for agricultural infrastructure against climate change.

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Estimating Wood Weight Change on Air Drying Times for Three Coniferous Species of South Korea

  • Lee, Daesung;Choi, Jungkee
    • Journal of Forest and Environmental Science
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    • v.32 no.3
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    • pp.262-269
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    • 2016
  • The purposes of this study are to calculate the green and dried weight using wood discs, to figure out weight change on air drying times, and to develop the model of wood disc weight change for Larix kaempferi, Pinus koraiensis, and Pinus densiflora. The variables affecting the weight change were investigated, and the pattern of weight change over time was figured out through linear models. When comparing the stem green weight calculated using wood discs in this study with the weight table of Korea Forest Service, the weight was not significantly different for L. kaempferi and P. koraiensis. On the other hand, in comparison of stem dried weight, the weight was significantly different in all of three species. In addition, various measurement factors were examined to figure out the relationship with weight change, and air drying times and disc diameter were found as significant independent variables. Finally, two linear models were developed to estimate air drying times of three species, fit statistics were significant for practical use.

Study on sensitivity of modal parameters for suspension bridges

  • Liu, Chunhua;Wang, Ton-Lo;Qin, Quan
    • Structural Engineering and Mechanics
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    • v.8 no.5
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    • pp.453-464
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    • 1999
  • Safety monitoring systems of structures generally resort to detecting possible changes of dynamic system parameters. Sensitivity analysis of these dynamic system parameters may implement these techniques. Conventional structural eigenvalue problems are discussed in the scope of those systems with deterministic parameters. Large and flexible structures, such as suspension bridges, actually possess stochastic material properties and these random properties unavoidably affect the dynamic system parameters. The sensitivity matrix of structural modal parameters to basic design variables has been established in this paper. Moreover, second order statistics of natural frequencies due to the randomness of material properties have been discussed. It is concluded from numerical analysis of a modem suspension bridge that although the second order statistics of frequencies are small relatively to the change of basic design variables, such as density of mass and modulus of elasticity, the sensitivities of modal parameters to these variables at different locations change in magnitude.

A Study on the Classification Of the Household Financial Strategies (가계 재무전략의 유형화에 관한 연구 -1999년과 2000년 한국노동패널자료를 중심으로-)

  • 박진영;문숙재
    • Journal of Families and Better Life
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    • v.22 no.2
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    • pp.85-95
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    • 2004
  • The purpose of this study was to classify the household financial strategies and find out variables affecting the type of the household financial strategies. The data of 3994 households from Korean Labor and Income Panel Study(1999-2000) were used. The major findings were as follows: (1) the household financial strategies were Residual Saver Type(44.6%), Unformal Institute Saver Type(13.3%), Financial asset Saver Type(16.7%), Real estate Saver Type(13.4%) and Diversities(12.0%). (2) The household financial strategy types were changed rapidly during short term. (3) In 3994 households, the variables which influence on the change of the household financial strategies were education, job, numbers of children, place of residence, home ownership. Similarly, in each type, the change of household financial strategies was significantly different according to the household characteristics variables.

A Method of Object Identification from Procedural Programs (절차적 프로그램으로부터의 객체 추출 방법론)

  • Jin, Yun-Suk;Ma, Pyeong-Su;Sin, Gyu-Sang
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.10
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    • pp.2693-2706
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    • 1999
  • Reengineering to object-oriented system is needed to maintain the system and satisfy requirements of structure change. Target systems which should be reengineered to object-oriented system are difficult to change because these systems have no design document or their design document is inconsistent of source code. Using design document to identifying objects for these systems is improper. There are several researches which identify objects through procedural source code analysis. In this paper, we propose automatic object identification method based on clustering of VTFG(Variable-Type-Function Graph) which represents relations among variables, types, and functions. VTFG includes relations among variables, types, and functions that may be basis of objects, and weights of these relations. By clustering related variables, types, and functions using their weights, our method overcomes limit of existing researches which identify too big objects or objects excluding many functions. The method proposed in this paper minimizes user's interaction through automatic object identification and make it easy to reenginner procedural system to object-oriented system.

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PSpice Implementation of Embedding Drive Synchronization using SC-CNN (SC-CNN을 이용한 임베딩 구동 동기기법의 PSpice 구현)

  • 배영철;김주완;손영우
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.05a
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    • pp.505-508
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    • 2003
  • In this paper, we introduce embedding drive synchronigation method using SC-CNN. SC-CNN provide us a good method to separate interconnected state variables of a system respectively and to make it possible to change current component to voltage component in the state variables. Using this advantage, We suggest another synchronization method called Embedding Drive Synchronization. Proposed Embedding Drive Synchronization change general drive synchronization method a little bit. we put transmitted signal between into the input of the state variables of the received part, not entirely replacing it. and we showed it proved.

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System Dynamics Model for Analyzing and Forecasting the National Energy-Economy-Environment(3E) Changes under Levying of Carbon Tax (탄소세 부과에 따른 국내 에너지-경제-환경(3E) 변화 분석 및 예측을 위한 시스템다이내믹스 모델 개발)

  • Song, Jae-Ho;Jeong, Suk-Jae;Kim, Kyung-Sup;Park, Jin-Won
    • Korean System Dynamics Review
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    • v.7 no.2
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    • pp.149-170
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    • 2006
  • In this paper, an energy-economy-environment dynamic simulation model was developed to using system dynamics methodology. It describes current energy-economy-environment systems and forecasts changes caused by levying of carbon tax. The model is composed of three modules: an energy module, an economic module and an environmental module. Variables are interrelated in each module, and three modules are linked by several linkage variables. Setting up the linkage variables is an important factor for the composition of the model. The simulation result shows a change of the national GDP, usage of energy, and $CO_2$ emissions under levying and reinvestment of carbon tax considering various scenarios for the charging cost.

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The Supply Water Algorithm for a Condensing Gas Boiler Control (콘덴싱가스보일러 제어를 위한 공급수알고리즘)

  • Han, Do-Young;Yoo, Byeong-Kang
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.6
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    • pp.441-448
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    • 2011
  • The energy consumption of a condensing gas boiler may be greatly reduced by the effective operation of the unit. In this study, the supply water algorithm for a condensing gas boiler control was developed by using the fuzzy logic. This includes the supply water set temperature algorithm, and the control algorithms of a gas valve, a blower and a pump. For the set temperature algorithm, the outside air temperature and the return water temperature were used as input variables. The supply water temperature difference and its slope were used as input variables of the gas valve and blower control algorithm. And the supply water temperature and the return water temperature were used as input variables of the pump control algorithm. In order to analyse performances of these algorithms, the dynamic model of a condensing gas boiler was used. The initial start-up test, the supply water set temperature change test, the outside air temperature change test, and the return water temperature change test were performed. Simulation results showed that algorithms developed in this study may be practically applied for the effective control of a condensing gas boiler.