• Title/Summary/Keyword: Long-term Dependence

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Decoupling Analysis between GHGs and GDP in Korea (국내 온실가스 배출량과 경제성장 간 장단기 비동조화 분석)

  • Kim, Daesoo;Lee, Sang-youp
    • Environmental and Resource Economics Review
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    • v.28 no.4
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    • pp.583-615
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    • 2019
  • This paper investigates the level of decoupling between greenhouse gas emissions and economic growth in Korea. Despite previous studies mainly stressed the existence of the Environmental Kuznets Curve, the lack of investigations in the level of decoupling constraints further policy suggestions. This study analyzes the level of decoupling in the short- and long-term, focusing on short-term volatility of GHG emissions income elasticity. In the long run, there is no decoupling in Korea because a robust causal relationship exists between GHGs, GDP, and fossil fuels. However, the short-term volatility is clearly identified under the long-term equilibrium(coupling), indicating there is the relative decoupling in the short run. The results show that fossil fuel dependence is a significant factor that increases short-term volatility(decoupling) and breaks the causal link(coupling) between GHGs and GDP.

Humidity Sensitivity of Hybrid Polyelectrolytes Prepared by the Sol-Gel Process

  • Lee Chil-Won;Park Hyung-Seok;Kim Jong-Gyu;Gong Myoung-Seon
    • Macromolecular Research
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    • v.13 no.2
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    • pp.96-101
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    • 2005
  • Thin-film humidity sensors were prepared using inorganic/organic hybrid polyelectrolytes, which were prepared from the sol-gel reaction of copolymers of [2-(methacryloyloxy)ethyl]dimethylpropylammonium bromide (MEPAB), n-butyl methacrylate (BMA), and 3-(trimethoxysilyl)propyl methacrylate (TSPM) with tetraethyl ortho-silicate (TEOS). The humidity-sensitive polyelectrolytes were composed of the copolymers having the following mole ratios of MEPAB, BMA, and TSPM: 60/30/10, 55/30/15, and 50/30/20. We found that the impedance varied with the content of MEPAB or TEOS; it ranged from $10^{7} to 10^{3}\Omega$ between 20 and $95\%$ relative humidity, which is the range required for a humidity sensor operating at ambient humidity. In addition we investigated a number of characteristics of these humidity sensors, such as their hysteresis, response time, temperature dependence, frequency dependence, water durability, and long-term stability.

Fabrication and Its Biomedical Application of the pH-ISFET Microprobe (pH-ISFET 마이크로프로브의 製作과 그 生醫學的 應用)

  • Lee, Kwang-Man;Sohn, Byung-Ki
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.11
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    • pp.1335-1341
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    • 1988
  • A pH-ISEFET microprobe for in vivo measurements has been fabricated by combining ISFET (SL-IIS) chip and capillary thin film reference electrode. A two-step TCE oxidation for the gate oxide layer and multilayer encapsulation using silicone rubber and epoxy were specially used for the improvement of the stability and temperature dependence of the ISFET's. The measured sensitivit, response time and temperature dependence of the pH-ISFET microprobes are 50 mV/pH, less than one second, and - 0.01 pH/$^{\circ}$ , respectively. By operating continuously more than 40 days, a long term stability of 0.016 pH/day is obtained. The result of pH monitoring of femoral arterial blood in a rabbit is fairly good agreement with the value of blood gas analysis.

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The Sustainability of Korean Management in Global Market: Competitive Strategy and Performance in Korean ICT Industry

  • Kwak, Kyu Tae;Cheon, Youngjoon;Lee, Bong Gyou
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.3
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    • pp.1344-1361
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    • 2016
  • ICT contents market is globally considered as an industry of high added value, where sustainability is accomplished through stories that cover wide range of consumers. However, the need for long-term internationalization strategy is growing as countless number of applications and games has pushed the local market to its limit. Thus, this research explored on the industrial characteristics and the internationalization of ICT contents firms through acquisition of competency. Based on Resource Dependence theory, the authors studied how pursuit of legitimacy and autonomy functioned in the expansion process of ICT contents firms. A survey analysis of 212 key decision makers of Korean ICT content firms were performed, to reveal that resource environment and interdependence must undergo a thorough consideration.

Empirical Equations for the Analysis of the Time Dependence of the Luminance Properties of LCD Panels and Backlights for TV Applications

  • Ryu, Jin-Sun;Kim, Su-Jin;Park, Seung-Mi;Ko, Jea-Hyeon
    • Journal of Information Display
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    • v.11 no.2
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    • pp.39-44
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    • 2010
  • The time dependences of the luminance properties of 55-inch CCFL and LED backlights and 32-inch FFL backlights with LCD panels were investigated during the warm-up time from the cold start. The long-term luminance maintenance curve of a standard CCFL was examined in a time window up to 5000 hours. These two time dependences are important characteristics from the viewpoint of initial picture quality and lifetime reliability, respectively. Empirical equations were suggested for the analysis of the time dependence of these luminance data. These approaches are expected to be helpful in predicting the luminance properties of backlights based on the luminance data obtained in a limited time window.

Resistive Humidity Sensor Using Phosphonium Salt-Containing Polyelectrolytes Based on the Mutually Cross-linkable Copolymers

  • Lee, Chil-Won;Gong, Myoung-Seon
    • Macromolecular Research
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    • v.11 no.5
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    • pp.322-327
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    • 2003
  • Two kinds of mutually cross-linkable copolymers were prepared to be used as humidity-sensing materials. The humidity-sensitive thin films consist of cross-linked polyelectrolytes of the following component: 4-vinylbenzyl dimethyl 2-(dimethylphosphino)ethyl phosphonium chloride (1)/ bis(2-methoxyethyl)itaconate (2)= 3/l, 2/l, 1/1 and 1/2 and 4-vinylbenzyl chloride (3)/ vinylbenzyl tributyl phosphonium chloride (4)= 3/l, 2/l, 1/1 and 1/2. The humidity sensor prepared from the reaction of 1/2= 2/l with 3/4= 2/l showed an average resistance of 723,36.2 and 2.42 ㏀ at 30, 60 and 90%RH, respectively. Temperature dependence, frequency dependence, and response time were measured and the reliability test such as water durability and long-term stability were also estimated.

A study of predicting irradiation-induced transition temperature shift for RPV steels with XGBoost modeling

  • Xu, Chaoliang;Liu, Xiangbing;Wang, Hongke;Li, Yuanfei;Jia, Wenqing;Qian, Wangjie;Quan, Qiwei;Zhang, Huajian;Xue, Fei
    • Nuclear Engineering and Technology
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    • v.53 no.8
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    • pp.2610-2615
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    • 2021
  • The prediction of irradiation-induced transition temperature shift for RPV steels is an important method for long term operation of nuclear power plant. Based on the irradiation embrittlement data, an irradiation-induced transition temperature shift prediction model is developed with machine learning method XGBoost. Then the residual, standard deviation and predicted value vs. measured value analysis are conducted to analyze the accuracy of this model. At last, Cu content threshold and saturation values analysis, temperature dependence, Ni/Cu dependence and flux effect are given to verify the reliability. Those results show that the prediction model developed with XGBoost has high accuracy for predicting the irradiation embrittlement trend of RPV steel. The prediction results are consistent with the current understanding of RPV embrittlement mechanism.

Possibility of Chaotic Motion in the R&D Activities in Korea

  • Loh, Jeunghwee
    • Journal of Information Technology Applications and Management
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    • v.21 no.3
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    • pp.1-17
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    • 2014
  • In this study, various characteristics of R&D related economic variables were studied to analyze complexity of science and technology activities in Korea, as reliance of R&D activities of the private sector is growing by the day. In comparison to other countries, this means that it is likely to be fluctuated by economic conditions. This complexity characteristic signifies that the result of science and technology activities can be greatly different from the anticipated results - depending on the influences from economic conditions and the results of science and technology activities which may be unpredictable. After reviewing the results of 17 variables related to science and technology characteristics of complex systems intended for time-series data - in the total R&D expenditure, and private R&D expenditure, numbers of SCI papers, the existence of chaotic characteristics were. using Lyapunov Exponent, Hurst Exponent, BDS test. This result reveals science and technology activity of the three most important components in Korea which are; heavy dependence on initial condition, the long term memory of time series, and non-linear structure. As stable R&D investment and result are needed in order to maintain steady development of Korea economy, the R&D structure should be less influenced by business cycles and more effective technology development policy for improving human resource development must be set in motion. And to minimize the risk of new technology, the construction of sophisticated technology forecasting system should take into account, for development of R&D system.

The Effects of Structural Factors of Administered Channels on the Retailer's Trust in the Supplier and Long-Term Orientation: Focusing on the Moderating Effect of Relationship Lifecycle (관리형 유통경로의 구조적 요인이 소매상의 공급자 신뢰와 장기지향성에 미치는 영향: 관계수명주기의 조절효과)

  • Park, Jong-Hee;Kim, Do-Yle;Kim, Seon-Hee
    • Journal of Distribution Research
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    • v.16 no.1
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    • pp.65-93
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    • 2011
  • This paper aims to explore how relational constructs(supplier's idiosyncratic investment, retailer's dependence, and dyadic communication) impact the buyer's trust across the relationship lifecycle. Companies make great efforts to create trust and maintain long-term relationship with buyers. Buyer and supplier relationships evolve through distinct lifecycles. In each phase, buyers and suppliers exhibit different patterns of behaviour. Also, they have different attitudes toward, and expectation of, one another. In this study, the final outcome investigated is long-term orientation from the buyer's perspective. Data were collected from 296 survey questionnaires of retailers engaging in Crops Protected Material industry in Korea. Exploratory factor analysis and confirmatory factor analysis were used to purify the measurement scales. And structural equation analysis and Chow test were used to test the hypotheses. The result indicates that the effect of retailer's dependence on the trust is greatest. Especially, the effect of dependence is growing as the relationship has developed. Supplier's idiosyncratic investment increases trust in the early phase, while it is not found to affect trust in the maturity phase. In the early phase, the determination of trust begins to be increasingly influenced by partner's relationship investment only because other clues are not observed yet. Reciprocal communication has a positive effect on trust, and long-term orientation is directly influenced by retailer's trust. Communication's effect is greater in the build-up phase than in the maturity phase. A limitation of this study is the unequal sample size in each of the relationship phases. Literature has suggested that the effects of relational constructs on outcomes are different across relationship phases. This study shows that different relational constructs have different effects on trust depending upon the relationship phase.

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A Study on the Linear Decision Rule and the Search Decision Rule for Aggregate Planning (I) (총괄계획을 위한 선형결정법과 탐색결정법에 관한 연구 (I))

  • 고용해
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.6 no.8
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    • pp.63-71
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    • 1983
  • Aggregate planning coordinate the control variable over long-term to apply a demand variable and forcasting. In order to necessary the goal that doesn't make an inter-contradiction and explicitly defined. We made a considerable point of system approach for scheduling establishment. It include the control variables of aggregate planning : 1) employment 2) over time working and idle time 3) inventory 4) delivery delay S) subcontract 61 long - term facility capacity. Each variables composed of pure strategy as like a decision of inventory level, a change of employment level, etc. md alternative costs make a computation on the economic foundation. But the optimum alternative costs represent the mixed pure strategy. The faults of this method doesn't optimum guarantee a special scheduling as well as increasing a number of alternative combination. Theoretical, Linear Decision Rule make an including all variables, but it is almost impossible for this model to develope actually And also make use of the aggregate planning problem for developing system approach : LDR, heuristic model, Search Decision Rule, all kind of computers, simulation. But these models are very complex, each variables get an extremely inter-dependence. So this study be remained by theory level, some approach methods has not been brought the optimum solution to apply in every cases.

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