• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권3호
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• pp.896-915
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• 2023

The network function virtualization (NFV) uses virtualization technology to separate software from hardware. One of the most important challenges of NFV is the resource management of virtual network functions (VNFs). According to the dynamic nature of NFV, the resource allocation of VNFs must be changed to adapt to the variations of incoming network traffic. However, the significant delay may be happened because of the reallocation of resources. In order to balance the performance between delay and quality of service, this paper firstly made a compromise between VNF migration and energy consumption. Then, the long short-term memory (LSTM) was utilized to forecast network traffic. Also, the asymmetric loss function for LSTM (LO-LSTM) was proposed to increase the predicted value to a certain extent. Finally, an experiment was conducted to evaluate the performance of LO-LSTM. The results demonstrated that the proposed LO-LSTM can not only reduce migration times, but also make the energy consumption increment within an acceptable range.

• 자원ㆍ환경경제연구
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• 제21권4호
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• pp.809-850
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• 2012

본 연구는 개별 국가 혹은 지역 단위 배출권 거래제도의 국제적 연계 가능성에 대비하기 위해 한 중 일 3국간의 배출권 거래제도 연계 시 예상되는 경제 환경적 영향을 분석하기 위해 수행되었다. 이를 위해 연산가능 일반균형모형을 통해 3국간 배출권 거래제 도입의 경제 환경적 영향을 분석하였다. 분석결과 한 중 일 3국간 탄소시장의 연계는 국가별로 다양한 측면에서 복잡한 영향을 미치게 됨을 확인할 수 있다. 한 중 일 배출권 거래제 연계 시행은 3국 전체의 실질 GDP를 증가시키는 긍정적 효과가 있음에도 불구하고 연계로 인한 이익의 국가간 분배가 불균형적임은 물론 실질 소비나 고용 등의 측면에서는 탄소시장 연계가 3국 전체적으로도 오히려 부정적인 영향을 초래할 수 있다는 점에서 반드시 긍정적인 효과만을 담보하는 것은 아니다. 특히 배출권 매입국인 한국과 일본의 소득 소비 고용 감소 및 에너지 의존도 증가, 배출권 매출국인 중국의 생산 감소 및 해외 이전 가능성은 3국간 탄소시장의 연계의 장애요인으로 작용할 수 있다. 3국간 탄소시장 연계를 통한 긍정적 효과를 최대한 유지하면서 예상되는 부정적 효과를 최소화하기 위해서는 배출권 수입 관세나 수입배출권 할인과 같은 보완적 정책수단의 개발 적용이 필요하다.

• 자원ㆍ환경경제연구
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• 제15권4호
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• pp.591-642
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• 2006

본고에서는 우선 배출권거래에 대하여 시간적 거래 허용 여부에 초점을 맞추어 정산기간을 1년으로 정한 단위기간정산 배출권거래제와 5년으로 설정한 다기간정산 배출권거래제에 대한 경제적 효과를 비교분석하고, 둘째로는 배출권의 초기할당 방식에 따른 일률 할당, 에너지소비 기준 할당, 부가가치 기준 할당 생산액 기준 합당 등의 할당방식의 차이가 어떠한 경제적 효과의 차이를 가져오는지를 분석하였다. 이러한 분석을 위하여 정책효과 분석에 적합하고 장기적인 정책예시효과를 파악할 수 있는 동태적 연산일반균형 모형을 이용하였으며, 배출권거래제에 참여하는 산업을 8개 에너지다소비산업으로 설정하여 분석하였다. 그 결과, 시간적 거래가 허용되는 다기간정산 배출권거래제에서 정산기간 동안 그 잔반기에 배출권을 팔고 후반기에 구매하는 형태의 시점간 거래가 이루어지는 것으로 나타났다. 이러한 현상은 시점간 거래를 허용할 경우 배출권을 저축하는 유인을 발생시킬 수 있다는 Kling and Rubin (1997) 의 분석과 일치한다. 경제적 효과를 비교분석한 결과, 배출권거래가 허용되는 경우가 개별 이행의 경우보다 GDP 손실이 작은 것으로 나타났다. 한편, 단위기간정산 배출권거래제와 다기간정산 배출권거래제를 비교하는 경우, 정산기간이 길어질수록 시점간 거래를 허용하는 다기간정산 배출권거래제의 GDP 손실이 작은 것으로 나타났다. 할당방식에 따른 GDP 손실을 비교하는 경우, 장기적으로 부가가치 기준의 초기할당방식이 다른 할당방식보다 GDP손실이 작은 것으로 나타났다.

• KEPCO Journal on Electric Power and Energy
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• 제2권3호
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• pp.377-382
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• 2016

In 2013, a total capacity of 591.3 MW of installed wind power generation was achieved in Korea, with a total of 1,139 MWh of wind energy generated that year. More wind power plants will be installed in the coming years, and it is important to develop methods to reduce the output variability of these resources so as to provide stable power to the power grid of Korea. In this regard, this paper proposes the use of energy storage system (ESS) as a means to stabilize the output variability of wind power plants. Presented in this paper is a method that uses Discrete Fourier Transform (DFT) to determine the ESS capacity needed to provide a stable power output for ancillary services such as frequency regulation, economic dispatch, and emergency reserves. In the first step of the proposed method, four regions (namely, Samdal, Yeongdeok, Yeongyang, and Gangwon) in Korea that had the most wind power generation capacity were selected for analysis. In the second step, the individual and aggregated wind power outputs of the selected regions in 2013 were obtained This information was then used in the third step, where DFT analysis of the power outputs was used to drive the magnitudes of the output variation. And finally, the ESS capacity requirements needed to provide different ancillary services were determined based on the magnitudes of the output variation.

• Journal of Radiation Protection and Research
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• 제43권1호
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• pp.1-9
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• 2018

Background: In this study, we investigate the image quality of virtual monochromatic images synthesized from dual-energy computed tomography (DECT) at voltages of 80/140 kV and 100/140 kV. Materials and Methods: Virtual monochromatic images of a phantom are synthesized from DECT scans from 40 to 70 keV in steps of 1 keV under the two combinations of tube voltages. The dose allocation of dual-energy (DE) scan is 50% for both low- and high-energy tubes. The virtual monochromatic images are compared to single-energy (SE) images at the same radiation dose. In the DE images, noise is reduced using the 100/140 kV scan at the optimal monochromatic energy. Virtual monochromatic images are reconstructed from 40 to 70 keV in 1-keV increments and analyzed using two quality indexes: noise and contrast-to-noise ratio (CNR). Results and Discussion: The DE scan mode with the 100/140 kV protocol achieved a better maximum CNR compared to the 80/140 kV protocol for various materials, except for adipose and brain. Image noise is reduced with the 100/140 kV protocol. The CNR values of DE with the 100/140 kV protocol is similar to or higher than that of SE at 120 kV at the same radiation dose. Furthermore, the maximum CNR with the 100/140 kV protocol is similar to or higher than that of the SE scan at 120 kV. Conclusion: It was found that the CNR achieved with the 100/140 kV protocol was better than that with the 80/140 kV protocol at optimal monochromatic energies. Virtual monochromatic imaging using the 100/140 kV protocol could be considered for application in breast, brain, lung, liver, and bone CT in accordance with the CNR results.

• 한국산업정보학회논문지
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• 제29권3호
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• pp.67-77
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• 2024

공장의 에너지 효율을 높이는 방안 중 공정 스케줄링은 제조 공정에서 자원을 최적으로 할당하여 제품의 생산 계획을 수립하는 활동이다. 그러나 야간 근로가 불가피한 경우에는 이러한 전략이 효과적으로 적용되지 않을 수 있다. 또한, 생산 요구량의 지속적인 변화로 인해 실제 공장에서의 적용에 어려움이 있다. 최근에는 전기자동차의 보급이 급증함에 따라 전기자동차 배터리를 에너지 저장 시스템으로 활용하는 기술이 주목을 받고 있다. 이러한 배터리를 활용한 기술은 공장 에너지 관리를 위한 대안이 될 수 있다. 본 논문에서는 전기자동차 배터리를 활용한 공장 에너지 관리 방안을 제안한다. 제안된 방안은 전기자동차 배터리 충전 상태 및 TOU(Time-of-use)를 고려하여 PSCAD/EMTDC 소프트웨어에서 분석된다. 제안된 방안은 예측된 전력 사용량과 TOU를 고려하여 수립된 공정 스케줄링과 비교 분석된다. 결과적으로 공정 스케줄링은 하루에 4,152원, 제안된 방안은 7,286원의 전기 요금을 절감하였다. 본 논문을 통해 공장 에너지 관리를 위해 전기자동차 배터리 활용 가능성을 확인할 수 있었다.

• 환경생물
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• 제21권4호
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• pp.400-404
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• 2003

This study was to evaluate the effects of gamma irradiation on the germination, nutrient concentrations and growth of spinach and radish. Both the spinach and radish seeds exhibited relatively higher germination rates in response to the low doses of gamma irradiation compared to the non -irradiated control. Leaf DW of the radish did not respond to gamma irradiation but that of the spinach increased significantly in response to a gamma radiation of 4 Gy (P< 0.05). Leaf growth parameters of the spinach including the leaf area and SLA (leaf area/leaf dry weight) also demonstrated increased responses to gamma irradiation. R/S (root dry weight/shoot dry weight), root DW and root length of the spinach exhibited a positive response to gamma irradiation while those of the radish did not. In contrast, SRL (root length/root dry weight) significantly decreased with gamma irradiation at 8 Gy for the spinach, but not for the radish. The tissue nitrogen concentrations of the spinach showed an increased response to gamma irradiation while that of the radish did not. Furthermore, higher concentrations of phosphorus, potassium, calcium and magnesium were found in the irradiated spinach, but not in the irradiated radish. It seems that the non-specific physiological and/or biochemical activities of spinach might be accelerated by gamma irradiation, possibly accounting for the stimulation of nutrient uptake from the root media and early biomass accumulation in the current study.

• 척추신경추나의학회지
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• 제10권1호
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• pp.75-86
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• 2015

Objectives : The purpose of this study is to compare the effect of Chuna manual treatment and Chuna manual treatment with self muscle energy techniques on patients with pelvic malposition Methods : Random allocation was done. We used Chuna manual treatment to control group and Chuna manual treatment with self muscle energy techniques to experimental group. These patient's pelvic malposition were checked by Leg length analysis, measuring Innominate measurement length, obturator foramen size and height of femur head. Results : 1)After the 3 weeks treatment, patients' inequality of leg length and Innominate measurement length were significantly reduced. 2)There was no significant difference between control group and experimental group. Conclusions : Chuna manual treatment and Chuna manual treatment with self muscle energy techniques are considered to be effective and useful in patients with pelvic malposition. But there was no significant difference between control group and experimental group.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2011년도 학술발표회
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• pp.3-3
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• 2011

After the dissolution of the Soviet Union, the Kra-Araks Basin (KAB) became an international river basin with respect to the South Caucasus states of Armenia, Azerbaijan, and Georgia. However, there are no agreements regarding water allocation, water quality, or ecosystem maintenance among the aforementioned riparians. The main water problems in the basin include not only water quantity and quality, but also the lack of joint management. The aforementioned countries share many similar circumstances: location in a politically unstable but strategic region bureaucratic and structural issues; and more importantly, ongoing ethnic and related conflicts. Despite these obstacles, the countries recognize that they depend greatly on the basin, whose waters they must share. To that end, they proposed and participated in the joint NATO-OSCE South Caucasus River Monitoring (SCRMP) project between 2002 and 2009.The SCRMP sought to investigate and characterize the surface water quality in the KAB by providing equipment and training to all three countries. Several years' worth of water quality data were collected in the KAB: major ions; heavy metals; POPs (persistent organic pollutants); and radionuclides; The North Atlantic Treaty Organization (primary funder) and the Organization for Security and Co-operation in Europesupported the SCRMP not only to build capacity but also to promote cooperation and minimize conflict over water and other resources, thus providing a measure of security for Europe and other regions. The South Caucasus is a strategically-important region, functioning as a bridge between Asia and Europe. Energy-rich Azerbaijan seeks to become a key player in trade by serving as a transportation and energy hub between the energy and mineral-rich Central Asian KUT countries (Kazakhstan, Uzbekistan, and Turkmenistan) and Western Asia, Europe, and other areas. The presentation will summarize the scientific results of the SCRMP, elucidate the regional water-energy-security nexus, discuss future work in the region, and explain why the world needs to be concerned about the KAB and the entire South Caucasus.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.660-673
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• 2022

In achieving carbon neutrality and the hydrogen economy, the estimation of H₂ cost is critical in terms of CCU technologies. This study analyzes LCOH of hydrogen produced by the carbon utilization unit with methane reforming and CO₂ from thermal power plant. LCOH for H₂ made with CO is estimated in three ways of Joint Cost Allocations with financial performance risk assessment. Regarding cost analysis, the zero value of LCOH is $6,003/ton. We found that the CCU technology has economic feasibility in terms of profitability. The sensitivity analysis result shows that the input ratio is more influential to the LCOH than other variables. Risk analysis presents the baseline price of zero value of LCOH - $8,408/ton, which is higher than the cost analysis - $6,003/ton. Mainly, the price variability of natural gas primarily affects the LCOH. The study has significant value in analyzing the financial performance risks as well as the cost of H₂ produced by a Plasma-based CCU system.