• Advances in Energy Research
• /
• 제7권2호
• /
• pp.101-121
• /
• 2020

Coal has made a wonderful contribution to the production of cheap electricity. Coal based power plants have been the backbone of world's electricity for a long time now. Coal while being cheap and easily available is also a source of various solid, liquid and gaseous effluents which are responsible for the environmental degradation. Environmental issues caused by coal need to be studied and analyzed, then a common global consensus must be formed. Efficient action must be taken against each and every type of pollutant that is produced by this particular industry. The research aims to provide a brief overlook of the environmental impact of India's coal-based power plants. The aim of this study is to introduce a novel environmentally feasible energy scenario for the future of Indian power sector which has been named as "OPES". OPES is mathematically simulated using the combination of GAMS and LEAP. OPES is simple to comprehend and can be reproduced easily for other case studies as well. Results show that OPES can help the Indian power sector to minimize its environmental impact without causing any problems in the energy supply.

• Nuclear Engineering and Technology
• /
• 제52권12호
• /
• pp.2821-2835
• /
• 2020

The phenomenon identification and ranking table (PIRT) is an important basis in the nuclear power plant (NPP) thermal-hydraulic analysis. This study focuses on the importance ranking of the input parameters when lacking the PIRT, and the target scenario is the small break loss of coolant accident (SBLOCA) in a pressurized water reactor (PWR) CPR1000. A total of 54 input parameters which might have influence on the figure of merit (FOM) were identified, and the sensitivity measure of each input on the FOM was calculated through an optimized moment-independent global sensitivity analysis method. The importance ranking orders of the parameters were transformed into the Savage scores, and the parameters were categorized based on the Savage scores. A parameter importance ranking table for the SBLOCA scenario of the CPR1000 reactor was obtained, and the influences of some important parameters at different break sizes and different accident stages were analyzed.

• 한국프랜차이즈경영연구
• /
• 제14권4호
• /
• pp.1-16
• /
• 2023

Purpose: Previous studies show that perceived CSR motives have a significant impact on company evaluations. However, consumer responses to CSR motives vary depending on CSR motives. From this perspective, this study investigates the impact of CSR motives on consumers' responses in the context of food and beverage franchise companies using a scenario. Research design, data, and methodology: For achieving the purposes of the study, an example of a domestic food and beverage franchise company actively carrying out CSR activities was presented. Data was collected from 304 respondents aged 20 or older who were aware of CSR activities. The respondents answered the questionnaire after reading the scenario. The data was analyzed with SPSS 28.0 and SmartPLS 4.0 program. Result: Values-driven motive and strategic motive influence authenticity, while stakeholder-driven motive and egoistic motive did not influence authenticity. Values-driven motive influences on attitude, while stakeholder-driven motive, strategic motive and egoistic motive didn't. Lastly, authenticity influences attitude. Conclusions: Companies need to be aware that consumers may infer different motives for their CSR activities, and pay close attention to consumers' perceived motives from the planning stage of CSR activities. In particular, companies should focus on the values-driven motive and the strategic motive when planning CSR activities.

• Ocean and Polar Research
• /
• 제34권2호
• /
• pp.253-264
• /
• 2012

In the northwestern Pacific, spawning of the common squid, Todarodes pacificus, occurs at continental shelf and slope areas of 100-500 m, and the optimum temperature for the spawning and survival of paralarvae is assumed to be $18-23^{\circ}C$. To predict the spawning ground of Todarodes pacificus under future climate conditions, we simulated the present and future ocean circulations, using an East Asia regional ocean model (Modular Ocean Model, MOM version3), projected by two different global climate models (MPI_echam5, MIROC_hires), under an IPCC SRES A1B emission scenario. Mean climate states for 1990-1999 and 2030-2039 from 20th and 21th Century Climate Change model simulation (from the IPCC 4th Assessment Report) were used as surface conditions for simulations, and we examined changes in spawning ground between the 1990s and 2030s. The results revealed that the distribution of spawning ground in the 2030s in both climate models shifted northward in the East China Sea and East Sea, for both autumn and winter populations, compared to that of the 1990s. Also, the spawning area (with $1/6^{\circ}{\times}1/6^{\circ}$ grid) in the 2030s of the autumn and winter populations will decline by 11.6% (MPI_echam5) to 30.8% (MIROC_hires) and 3.0% (MPI_echam5) to 18.2% (MIROC_hires), respectively, from those of the 1990s.

• 한국수소및신에너지학회논문집
• /
• 제31권6호
• /
• pp.605-613
• /
• 2020

In July and October of this year, the government announced the 'Green new deal plan within the Korean new deal policy' and 'Strategies for proliferation of future vehicles and market preoccupation'. And, in response to changes in the global climate agreement, it has decided to expand green mobility such as electric vehicles and hydrogen electric vehicles with the aim of a "net-zero" society. Accordingly, the goal is to build 310 hydrogen refueling stations along with the supply of 60,000 hydrogen vehicles in 2022, and the hydrogen infrastructure is being expanded. however, it is difficult to secure hydrogen infrastructure due to expensive construction costs and difficulty the selection of a site. In Korea, it is possible to build a mobile hydrogen station according to the safety standards covering special case of the Ministry of Industry. Since the mobile hydrogen station can be charged while moving between authorized place, it has the advantage of being able to meet a large number of demands with only one hydrogen refueling station, so it is proposed as a model suitable for the early market of hydrogen infrastructure. This study demonstrates the establishment of a hydrogen refueling station by deriving a virtual accident scenario for leakage and catastrupture for each facility for the risk factors in a mobile hydrogen station, and performing a quantitative risk assessment through the derived scenario. Through the virtual accident scenario, direction of demonstration and implications for the construction of a mobile hydrogen refueling station were derived.

• Journal of Positioning, Navigation, and Timing
• /
• 제10권3호
• /
• pp.169-177
• /
• 2021

In this paper, we propose a novel global navigation satellite system (GNSS) spoofing detection technique through an array antenna-based direction of arrival (DoA) estimation of satellite and spoofer. Specifically, we consider a sophisticated GNSS spoofing attack scenario where the spoofer can accurately mimic the multiple pseudo-random number (PRN) signals since the spoofer has its own GNSS receiver and knows the location of the target receiver in advance. The target GNSS receiver precisely estimates the DoA of all PRN signals using compressed sensing-based orthogonal matching pursuit (OMP) even with a small number of samples, and it performs spoofing detection from the DoA estimation results of all PRN signals. In addition, considering the initial situation of a sophisticated spoofing attack scenario, we designed the algorithm to have high spoofing detection performance regardless of the relative spoofing signal power. Therefore, we do not consider the assumption in which the power of the spoofing signal is about 3 dB greater than that of the authentic signal. Then, we introduce design parameters to get high true detection probability and low false alarm probability in tandem by considering the condition for the presence of signal sources and the proximity of the DoA between authentic signals. Through computer simulations, we compare the DoA estimation performance between the conventional signal direction estimation method and the OMP algorithm in few samples. Finally, we show in the sophisticated spoofing attack scenario that the proposed spoofing detection technique using OMP-based estimated DoA of all PRN signals outperforms the conventional spoofing detection scheme in terms of true detection and false alarm probability.

• 방사선산업학회지
• /
• 제17권3호
• /
• pp.265-273
• /
• 2023

To effectively and safely manage the radiation exposure to nuclear power plant (NPP) workers in accidents, major overseas NPP operators such as the United States, Germany, and France have developed and applied realistic 3D model radiation dose assessment software for workers. Continuous research and development have recently been conducted, such as performing NPP accident management using 3D-VR based on As Low As Reasonably Achievable (ALARA) planning tool. In line with this global trend, it is also required to secure technology to manage radiation exposure of workers in Korea efficiently. Therefore, in this paper, it is described the application method and assessment results of radiation exposure scenarios for workers in response to accidents assessment technology, which is one of the fundamental technologies for constructing a realistic platform to be utilized for radiation exposure prediction, diagnosis, management, and training simulations following accidents. First, the post-accident sampling after the Loss of Coolant Accident(LOCA) was selected as the accident and response scenario, and the assessment area related to this work was established. Subsequently, the structures within the assessment area were modeled using MCNP, and the radiation source of the equipment was inputted. Based on this, the radiation dose distribution in the assessment area was assessed. Afterward, considering the three principles of external radiation protection (time, distance, and shielding) detailed work scenarios were developed by varying the number of workers, the presence or absence of a shield, and the location of the shield. The radiation exposure doses received by workers were compared and analyzed for each scenario, and based on the results, the optimal accident response scenario was derived. The results of this study plan to be utilized as a fundamental technology to ensure the safety of workers through simulations targeting various reactor types and accident response scenarios in the future. Furthermore, it is expected to secure the possibility of developing a data-based ALARA decision support system for predicting radiation exposure dose at NPP sites.

• 한국수자원학회논문집
• /
• 제46권3호
• /
• pp.253-265
• /
• 2013

본 연구에서는 쾨펜의 기후대 구분법을 이용하여 현재 아시아 지역(경도 $55.6^{\circ}{\sim}149.3^{\circ}$, 위도 $-11.5^{\circ}{\sim}53.0^{\circ}$) 기후대를 분석하고, IPCC SRES A2 시나리 오상황에서의 기후대 변화를 전망하였다. 이와 더불어 기후대 구분의 기준이 되는 강수 및 기온자료의 시공간적 변동성을 분석하였다. 기후요소의 변동성을 분석한 결과, 2080년경에는 기준기간(1991~2010)에 비해 기온은 $4.0^{\circ}C$, 강수량은 12% 증가할 것으로 전망되었다. 공간적으로는 기온의 경우 고위도 지역이 저위도 지역보다 기온상승폭이 크게 나타났으며 강수량은 지역적 편중이 심화될 것으로 전망되었다. 기후대 변화를 전망한 결과, 대체로 온난한 기후대의 면적은 증가한 반면, 한랭한 기후대의면적은 감소하는 것으로 분석되었다. 기준기간 대비 2080년경에는 열대 기후대(A)의 경우 7.2%, 건조 기후대(B)는 1.9% 증가하였으며 온대 기후대(C), 냉대 기후대(D), 한대 기후대(E)는 각각 -2.4%, -4.9%, -1.8% 감소하는 것으로 전망되었다. 이러한 결과는 지구온난화에 따른 기온 증가와 사막화의 영향에 기인한 것으로 판단된다.

• 한국지리정보학회지
• /
• 제23권4호
• /
• pp.120-139
• /
• 2020

본 연구에서는 CLUE-s(Conversion of Land Use and its Effects at Small regional extent)와 RCP(Representative Concentration Pathway) 4.5 및 8.5 HadGEM3-RA(Hadley Centre Global Environmental Model version 3 Regional Atmosphere)시나리오를 사용하여 미래 농지이용 변화와 기후변화가 관개 필요수량에 미치는 영향을 평가하였다. 논산시(55,517.9ha)의 농지이용 항목으로 논, 밭, 시설재배지를 고려하고 DIROM (Daily Irrigation Reservoir Operation Model)을 이용해 탑정저수지 수혜구역(5,713.3ha)에 대한 관개 필요수량(Irrigation Water Requirement, IWR)을 추정하였다. CLUE-s를 이용한 미래 농지이용 변화를 모의하기 위해 환경부의 2007년, 2013년, 2019년의 토지피복도 6개 항목(수역, 시가지, 논, 밭, 산림, 시설재배지)을 적용하였다. 그 결과, 2100년은 2013년에 비해 논과 밭이 5.0%, 7.6% 감소했으며, 시설재배지는 24.7% 증가하는 것으로 전망되었다. 미래의 농지이용과 기후변화를 모두 고려한 경우의 RCP 4.5 및 RCP 8.5 모두 2090s(2090~2099) IWR은 미래 기후변화만 고려한 경우에 비해 논과 밭에서는 각각 2.1%, 1.0% 감소하고 시설재배지에서는 11.4% 증가하는 것으로 전망되었다.

• Korean Chemical Engineering Research
• /
• 제61권4호
• /
• pp.496-504
• /
• 2023

세계 각국은 지구온난화로 인한 피해가 증가함에 따라 화석연료를 대신해 탄소배출 없이 지속 가능하게 이용할 수 있는 새로운 에너지 자원들을 찾기 위하여 노력하고 있다. 전세계적으로 4차 산업이 고도화되며 전력수요가 급증했고, 상승하는 수요를 충족함과 동시에 온실가스 배출을 줄이기 위해 탄소비중이 적거나 없는 에너지원을 이용해 안정적인 전력수급계통을 확보하려는 움직임이 커지고 있다. 본 총설에서는 해외 탄소중립 시나리오와 화력발전 잔존여부에 따라 2가지 시나리오인 혁신, 안전으로 분류하여 정부의 탄소저감 목표를 비교 및 분석하였다. 또한, 국내 시나리오의 경우10차 전력수급기본계획의 전력수요 전망 및 온실가스 배출 현황을 연계하여 이를 토대로 탄소저감의 주축이 되는 에너지 분야인 전환, 수소, 수송, 탄소포집 및 활용 부문에서의 핵심 기술 동향 및 정부 주도의 정책흐름을 정리하여 탄소중립기술의 현황을 기술했다. 또한, 해외 시나리오 분석에서 시사되었던 에너지 분야의 주요 변화를 반영하여 국내 탄소저감 전략의 방향을 제시하였다.