• Korean System Dynamics Review
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• v.9 no.1
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• pp.125-141
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• 2008

It is very difficult to predict future demand/supply, price for resources with acceptable accuracy using regression analysis. We try to use system dynamics to forecast the demand/supply and price for nickel. Nickel is very expensive mineral resource used for stainless production or other industrial production like battery, alloy making. Recent nickel price trend showed non-linear pattern and we anticipated the system dynamic method will catch this non-linear pattern better than the regression analysis. Our model has been calibrated for the past 6 year quarterly data (2002-2007) and tested for next 5 year quarterly data(2008-2012). The results were acceptable and showed higher accuracy than the results obtained from the regression analysis. And we ran the simulations for scenarios made by possible future changes in demand or supply related variables. This simulations implied some meaningful price change patterns.

• Environmental and Resource Economics Review
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• v.24 no.1
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• pp.225-249
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• 2015

There are growing interests in the introduction of consumer's selective electricity tariff systems in order to enhance demand response in electricity market in Korea. Real time pricing (RTP) and Time of Use (TOU) are typical examples of demand response system through which electricity price is linked to real time demand. This paper adopts an agent-based model to analyze the effects of such demand system on the counsumers' electricity costs. The result shows that real time pricing system is effective to reduce electricity costs of consumers by providing more flexible tariff system, depending on each consumer's demand pattern. This finding could be used as a basis for supporting smart grid system in the presence of responsive demand environment.

• Environmental and Resource Economics Review
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• v.30 no.2
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• pp.237-268
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• 2021

As variable renewable sources rapidly increase due to the Energy Transition plan, integration cost of renewable sources to the power system is rising sharply. The increase in variable renewable energy reduces the capacity factor of existing traditional power capacity, and this undermines the efficiency of the overall power supply, and demand resources are drawing attention as a solution. In this study, we analyzed how much electric vehicle demand resouces, which has great potential among other demand resources, can reduce power supply costs if it is used as a flexible resource for renewable generation. As a methodology, a stochastic form of power system optimization model that can effectively reflect the volatile characteristics of renewable generation is used to analyze the cost induced by renewable energy and the benefits offered by electric vehicle demand resources. The result shows that virtual power plant-based direct control method has higher benefits than the time-of-use tariff, and the higher the proportion of renewable energy is in the power system, the higher the benefits of electric vehicle demand resources are. The net benefit after considering commission fee for aggregators and battery wear-and-tear costs was estimated as 67% to 85% of monthly average fuel cost under virtual power plant with V2G capability, and this shows that a sufficient incentive for market participation can be offered when a rate system is applied in which these net benefits of demand resources are effectively distributed to consumers.

• Environmental and Resource Economics Review
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• v.16 no.4
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• pp.901-922
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• 2007

To see how the electricity demand for air-conditioning responds to weather condition and what kind of weather condition works better in forecasting maximum daily electricity demand, four different regression models, which are linear, exponential, power and S-curve, are adopted. The regression outcome turns out that the electricity demand for air-conditioning is inclined to rely on the exponential model. Another major discovery of this study is that the electricity demand for air-conditioning responds more sensitively to the weather condition year after year along with the higher non-air-conditioning electricity demand. In addition, it has also been found that the discomfort index explains the electricity demand for air-conditioning better than the highest temperature.

• The Journal of Fisheries Business Administration
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• v.53 no.1
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• pp.55-72
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• 2022

The domestic catch of squid is decreasing every year. Import volume is increasing to replace these domestic products. Import volume is expected to increase in the future, so it is necessary to study import substitution. Therefore, in this study, after selecting frozen squid, which accounts for the majority of imported squid, as the target fish species, China, Chile and Peru, which account for the majority of frozen squid imports, will be selected as the target countries for analysis. Then, the demand function of squid is estimated using the Rotterdam model, the inverse Rotterdam model, AIDS and inverse AIDS, which are the simultaneous equation demand types, and then elasticity is derived. After that, these models are compared in terms of significance, theoretical fit and practical fit.

• Safety and Health at Work
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• v.11 no.3
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• pp.353-360
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• 2020

Background: Urban bus drivers work under conditions that are among the most demanding, stressful, and unhealthy with higher rates of mortality and morbidity as well as absenteeism and turnover. Methods: Drawing on the job demand-resource model, this study investigates the impacts of job characteristics on emotional exhaustion and the effects of emotional exhaustion on job outcomes (including job satisfaction, life satisfaction, organizational commitment, and turnover intention) in the context of bus drivers. Results: Using self-reported survey data collected from a sample of 320 Taiwanese urban bus drivers, results reveal that role overload and work-family conflict (as job demand factors) positively relate to emotional exhaustion, and organizational support (as a job resource factor) is negatively associated with emotional exhaustion. Emotional exhaustion has negative effects on both job satisfaction and organizational commitment. Job satisfaction positively leads to life satisfaction, whereas organizational commitment negatively relates to turnover intention. Conclusion: This study concludes that role overload and work-family conflict as two stressors related to job demands and organizational support as the job resource factor to affect emotional exhaustion which further influence well-being in bus driver context. The moderating effects of both extraversion and neuroticism on the relationship between job demands and emotional exhaustion are evident.

• Journal of Korean Society of Rural Planning
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• v.15 no.4
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• pp.1-10
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• 2009

Rural amenity is regarded as a breakthrough that can revitalize the rural communities. The demand for rural amenity development is also increasing since the urban people have growing incomes and leisure time. This study was implemented to survey the needs and application directions of rural amenity database. The survey questionnaires were collected from various related groups including industry, universities, administration and research institute. Two kinds of analysis of variance (ANOVA) were carried out in order to prioritize the building rural amenity resource map among four user groups and ten rural amenity resources. The result of survey showed that most of respondents had been aware of amenity resources and the industry group had the highest level of utilization in making decisions for rural development. Although the significant difference among groups was not shown in the priority, the priority in the construction of information map was shown the significant difference among 10 kinds of amenity resources. Landscape's map and traditional resource map were relatively higher priority than the other resource map.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.354-359
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• 2004

As we are approaching on the new paradigm for the water resource management. This is because there has been changed on the water resource environment. People want more water whenever they need, however increased absolute demand does not always meet the demand. Furthermore many water related social conflicts are getting increased in recent decades. Consequently, the emphasis of water policy became the core of water resource management. Therefore, research on the water resource policy should be diversified to derive prefer water management. In Korea this research has been done in recent, but within a very narrow view. We tried to evaluate the current status and suggest the direction of water resource policy.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1225-1228
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• 2011

This paper presents an advanced energy saving algorithm in building. It is important to aggregate a various demand side resource which is controllable on demand response environment. Previous demand side algorithm for building is restricted on peak power. In this paper, we suggest duty cycle algorithm for AHU on demand response to reduce the quantity of building power consumption. The test results show that the proposed algorithm is very effective.

• Journal of Korean Society of Rural Planning
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• v.10 no.1 s.22
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• pp.35-40
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• 2004

The expansion of demand associated with leisure, which has resulted from the elevated standard of living, has made the domestic tourist demand diversified. Recently, people, especially urban population, show the higher interest and need for environmentally friendly rural tourism. This study aims to grasp the utilization of recreation roles of tourist farms and then to evaluate the economic value for recreation roles of tourist farm using Traveling Cost Method. Data were collected from a survey in 2003. The results show that its value is 62,037 won per head annually and so the tourist farms play their role of connecting the urban population with rural amenity.