• 한국태양에너지학회 논문집
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• 제23권4호
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• pp.1-9
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• 2003

In this study, a manufacturing process for PV module has been developed using an automatic arraying equipment. It is expected that this process could improve the productivity and curtail the production cost in the photovoltaic module production line. From the results, it is proved that this process reduces Line-stop and enhances the productivity more than 15% a day which can be related directly to the production line cost.

• 펄프종이기술
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• 제36권3호
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• pp.83-90
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• 2004

Pulp mold is one of the famous environmental friendly materials, which made from re cycled materials such as old newsprints through the environmental friendly processes. Furthermore, the used pulp mold can be easily recycled and the pulp mold itself is biodegradable. However, the higher cost and some deficiency in physical properties of pulp mold have been considered as issues to be overcome for a substitute for polymeric packaging materials such as EPS (Expandable Polystyrene). The way for the optimization of a pulp mold mill was proposed in this report. The possible reduction of drying energy was calculated by using a computer simulation method, which could Provide the detailed information about mass balance of overall process. The simulated results showed a great possible curtailment of production cost by improving the forming systems, for example, increasing the temperature and the dryness of a wet pulp mold.

• 한국유기농업학회지
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• 제12권4호
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• pp.359-375
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• 2004

Recently, many researches on the biomass of the agricultural and livestock wastes are being conducted in several respects. The use of biomass is of benefit to the curtailment of oil import, environmental pollution decrease, global warming mitigation and so on. And, in the agricultural sphere, making use of agricultural byproducts can contribute to the revitalization of the agricultural industry and rural community. In other words, making new products or energy by using biomass have a possibility to be developed as a new industry. The industry can create new businesses and job opportunities for rural dwellers. Also, major 3 positive effects of market formation for the agricultural wastes, increase of the idle land use and creation of the new business are expected. However, the use of biomass may be difficult to secure a proper right as a market good in the autonomic market economy. It is necessary to establish or amend related laws or systematic tools for the revitalization of the biomass use. Also, it is required for the government to bear partial costs of the facilities and others in the beginning stage.

• 전력전자학회논문지
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• 제21권3호
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• pp.231-237
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• 2016

Recently, the interest in DC systems to achieve more efficient connection with renewable energy sources, energy storage systems, and DC loads has been growing extensively. DC systems are more advantageous than AC systems because of their low conversion losses. However, the DC-link voltage is variable during operation because of different random effects. This study focuses on DC voltage stabilization applied in stand-alone DC microgrids by means of voltage ranges, power management, and coordination scheme. The quality and stability of the entire system are improved by keeping the voltage within acceptable limits. In terms of optimized control, the maximum power should be tracked from renewable resources during different operating modes of the system. The ESS and VSDG cover the power shortage after all available renewable energy is consumed. Keeping the state of charge of the ESS within the allowed bands is the key role of the control system. Load shedding or power generation curtailment should automatically occur if the maximum tolerable voltage variation is exceeded. PSIM-based simulation results are presented to evaluate the performance of the proposed control measures.

• 전기전자학회논문지
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• 제23권1호
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• pp.173-180
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• 2019

재생에너지의 점유율 증가에 의하여 출력이 제한되는 사례가 발생하고 있다. 전형적으로 풍력발전의 발전량이 높고 부하가 낮은 새벽시간에 출력제한이 주로 발생하였으나, 태양광발전의 점유율이 증가하면서 낮 시간에 풍력발전의 출력이 제한되는 사례가 발생하고 있다. 현재의 전력계통 운영 상황에서는 태양광발전의 점유율이 증가할수록 풍력발전의 출력 제한이 더욱 증가시킬 것이며, 이는 풍력발전 운영자의 어려움을 가중시킬 것이다. 본 논문에서는 발전원 그리고 발전소별 출력 제한을 위하여 전력계통의 운영 어려움 유발하는 에너지원의 우선 제약을 기준으로 설정하여 기준에 따라 재생에너지의 출력 제한량을 분배하는 방안을 제시하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.55-58
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• 2008

Residential fuel cell cogeneration systems have gained much interest due to its high efficiency. In this study, we have performed numerical simulation of residential fuel cell cogeneration system which includes a fuel cell/grid hybrid system. The cogeneration system consists of 1kW PEFC, cooling system, inverter/converter and reformer. Several empirical models have been employed for respective components to improve the accuracy of the simulations. The load varies seasonally. The present simulations can successfully predict the characteristics of the hybrid cogeneration system and thus it can be utilized for establishing an optimal operating strategy of the system.

• 한국기계연구소 소보
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• 통권19호
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• pp.171-180
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• 1989

The automation of textile machinery in the fabric manufacture is strongly demanded in order to improve the industrial structure related to labour-force and cost curtailment, in addition, to keep step with the various and small production system and the consumption tendency requesting a high quality fabrics. In this thesis, the technology applying the computer to an air jet loom and characteristics obtained from it are derived. To efficently apply an automized and unmanned textile machinery, an air jet loom is equipped with the let-off, take-up and weft insertion device attached a central processing unit(CPU) which can automatically operate according to a program. As a result, an air jet loom is available for the factory automation, which has advantages including productivity promotion, high quality security, energy savings, specification & variety, efficient production control, in fabric manufacturing process.

• Journal of Electrical Engineering and Technology
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• 제13권4호
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• pp.1407-1418
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• 2018

Novel mechanism of customized adequacy formulation is proposed in order to enhance micro grids system reliability. The mechanism accounts for 2-levles of load curtailment, and is mainly based on probabilistic load profile and hybrid Distributed Generation (DG) units modeling. The two load curtailments are needed in order to ensure adequate technical constraints at steady state condition during islanding mode of operation. The effectiveness of the proposed formulation has been verified using system independent analytical expressions for the evaluation of both reliability and Expected Energy Not Served (EENS) indices. The evaluation has examined the impact of different penetration levels of Hybrid DG Units in case study islands. Results show the enhancement of the overall distribution system reliability and the recommended conditions for successful islanding mode of operation.

• 대한전기학회논문지:전력기술부문A
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• 제55권11호
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• pp.453-462
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• 2006

This paper evaluates the reliability of KEPCO system using TRELSS, which is a probabilistic reliability evaluation program for large-scaled power system. In order to reflect the characteristic of KEPCO system, the sensitivity of reliability indices such as LOLP, EDLC, EENS and Energy Curtailment for variations of TRELSS parameter and input data was analyzed. Additionally, probabilistic reliability of KEPCO system reflecting sensitivity analysis results was systematically evaluated and simulated. Finally, maximum acceptable FOR of KEPCO system to satisfy reliability criterion, which meet in process of establishing the basic plan for long-term electricity supply and demand is suggested.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.448-452
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• 2006

Many kinds of electric heating appliance is used by user interface and desire. Far infrared ray heating system can use a kind of main heating appliance. This paper gives un saving amounts, energy curtailment money and payback period between far infrared ray heating system and existing electric heating appliance - EHP, electric air heater, electric radiator, electric floor heating system - from economy analysis.