• 대기
• /
• 제18권1호
• /
• pp.33-41
• /
• 2008

This study provides an impact assesment of climate change on energy consumption, based on active-deal scenario. This approach assumes that the amount of electric energy consumption depends on human spontaneous acts against local (REC) has ben developed by using monthly mean temperature and monthly amount of electric energy consumption in the 6 major cities over the 19-205 period. The statistical model is utilized to estimate the past and future REEC, and to assess the economic benefits and damage in energy consumption sector. For an estimation of the future REEC, climate change scenario, which is generated by National Institute of Meteorological Research, is utilized in this study. According to the model, it is estimated that over the standard period (1999~2005), there might be economic benefits of about 31 bilion Won/year in Seoul due to increasing temperature than in the 1980s. The REC is also predicted to be gradually reduced across the Korean peninsula since the 2020s. These results suggest that Korea will gain economic benefits in the REC sector during the 21st century as temperature increases under global warming scenarios.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 C
• /
• pp.926-928
• /
• 1998

A fast optimization algorithm has been evolved from a simple two stage optimal power flow(OPF) algorithm for constrained power economic dispatch. In the proposed algorithm, we consider various constraints such as power balance, generation capacity, transmission line capacity, transmission losses, security equality, and security inequality constraints. The proposed algorithm consists of four stages. At the first stage, we solve the aggregated problem that is the crude classical economic dispatch problem without considering transmission losses. An initial solution is obtained by the aggregation concept in which the solution satisfies the power balance equations and generation capacity constraints. Then, after load flow analysis, the transmission losses of an initial generation setting are matched by the slack bus generator that produces power with the cheapest cost. At the second stage we consider transmission losses. Formulation of the second stage becomes classical economic dispatch problem involving the transmission losses, which are distributed to all generators. Once a feasible solution is obtained from the second stage, transmission capacity and other violations are checked and corrected locally and quickly at the third stage. The fourth stage fine tunes the solution of the third stage to reach a real minimum. The proposed approach speeds up the coupled LP based OPF method to an average gain of 53.13 for IEEE 30, 57, and 118 bus systems and EPRI Scenario systems A through D testings.

• Journal of Electrical Engineering and Technology
• /
• 제9권4호
• /
• pp.1240-1247
• /
• 2014

The applications of Distributed Generation (DG) in a smart distribution grid environment are widely employed especially for power balancing and supporting demand responses. Using these applications can have both positive and negative impacts on the distribution system. The sizing and location of their installations are the issues that should be taken into consideration to gain the maximum benefit from them when considering the economic aspects. This paper presents an application of the Bat Algorithm (BA) for the optimal sizing and siting of DG in a smart distribution power system in order to maximize the Benefit to Cost Ratio (BCR), subjected to system constraints including real and reactive power generation, line and transformer loading, voltage profile, energy losses, fault level as well as DG operating limits. To demonstrate the effectiveness of the proposed methodology and the impact of considering economic issues on DG placement, a simplify 9-bus radial distribution system of the Provincial Electricity Authority of Thailand (PEA) is selected for the computer simulation to explore the benefit of the optimal DG placement and the performance of the proposed approach.

• 한국항만경제학회지
• /
• 제18권2호
• /
• pp.109-133
• /
• 2002

The China entered World Trade Oganization(WTO) last year, thus opening its border to more - and freer - trade. With its foreign trade rapidly expanding and with economic growth continuing at a substantial -rate, China will be the largest container traffic generating country in the world. In the light of this potential trade bonanza, regional ports in North-East Asia strive to gain a competitive-edge. The Port of Busan, the world's third largest container port, wants to capture a significant share of the china's container cargoes. In this circumstance, development strategies of the Port of Busan are suggested as follows. First, to cope with increasing volumes, the New Busan Port on Gaduk island should be constructed without failure. Second, it is necessary to add modernized high-performance gantry cranes and to train crane operators' skill. Third, it needs to apply Dwell Time- Sliding Scale System for transshipment cargoes. Fourth, it needs to develop the EDI network in terminal areas or adjacent hub ports to exchange trustworthy and satisfactory informations Fifth, port authority -needs to enlarge designated Free Trade Zone to facilitate the free flow of cargoes. Sixth, the restoration of rail links between North and South Korea is abundantly clear. Thus it needs to enlarge railroad facilities in advance. Seventh, it needs to establish the Port Authority of Busan immediately. Finally, it needs to strengthen port sales and to open events like 'Marine Week 2001' regularly to attract potential canters or big shippers.

• Journal of Korea Trade
• /
• 제26권8호
• /
• pp.37-57
• /
• 2022

Purpose -International diplomacy is key for the cohesive economic growth of countries around the world. This study aims to identify the major topics discussed and make sense of word pairs used in sentences by Chinese senior leaders during their diplomatic visits. It also compares the differences between key topics addressed during diplomatic visits to developed and developing countries. Design/methodology - We employed three methods: word frequency, co-word, and semantic network analysis. Text data are crawling state and official visit news released by the Ministry of Foreign Affairs of the People's Republic of China regarding diplomatic visits undertaken from 2015-2019. Findings - The results show economic and diplomatic relations most prominently during state and official visits. The discussion topics were classified according to nine centrality keywords most central to the structure and had the maximum influence in China. Moreover, the results showed that China's diplomatic issues and strategies differ between developed and developing countries. The topics mentioned in developing countries were more diverse. Originality/value - Our study proposes an effective approach to identify key topics in Chinese diplomatic talks with other countries. Moreover, it shows that discussion topics differ for developed and developing countries. The findings of this research can help researchers conduct empirical studies on diplomacy relationships and extend our method to other countries. Additionally, it can significantly help key policymakers gain insights into negotiations and establish a good diplomatic relationship with China.

• Fisheries and Aquatic Sciences
• /
• 제1권2호
• /
• pp.255-259
• /
• 1998

This study was designed to evaluate the economic analysis of channel catfish production in 1998 based on fish value and total feed cost. Catfish received higher protein feeds with lesser amount based on the dietary protein levels, but received the constant total protein input for all treatments. Weight gain per pond for treatment 1 $(28\%\;protein,\;100\%\;of\;satiation)$ was higher (P<0.10) than for treatment 3 $(36\%\;protein,\;77.8\%\;of\;satiation)$, but not significantly higher than for treatment 2 $(32\%\;protein,\;87.5\%\;of\;satiation)$ at constant DE. At constant DE/P (treatments 4, 2 and 5), weight gain per pond for treatment 5 $(36\%\;protein,\;77.8\%\;of\;satiation)$ was lower (P<0.10) than for treatment 2, but not significantly lower than for treatment 4 $(28\%\;protein,\;100\%\;of\;satiation)$. At constant DE, feed conversion slightly improved as dietary protein level increased from $28\%\;to\;32\%$ and feed allowance decreased by $12.5\%$, but did not improve further as dietary protein level increased from $28\%\;to\;36\%$ and feed allowance decreased by $22.2\%$. At constant DE/P, feed conversion improved as dietary protein level increased from $28\%\;to\;32\%$ increased and feed allowance decreased by $12.5\%$, but did not improve as dietary protein level increased from $28\%\;to\;36\%$ and feed allowance decreased by $22.2\%$ Total feed cost for treatment 1 was slightly, but not significantly higher than for treatments 2 and 3 at constant DE. At constant DE/P, total feed cost for treatment 5 was higher (P<0.05) than for treatment 2, but not significantly higher than for treatment 4. Total value of fish ($ /ha) produced for treatment 1 was highest and lowest was for treatment 5. Return above feed cost was highest for treatment 1 and nearly the same as treatment 2. Return over feed cost for treatments 3 and 4 were slightly lower than for treatments 1 and 2. Economic analysis showed that feeding fish the diet containing $28\%$ protein and 3.08 kcal/g DE to satiation and the diet containing $32\%$ protein and 3.08 kcal/g DE to $87.5\%$ of satiation produced the highest profit to farmer.

• 산업경영시스템학회지
• /
• 제39권4호
• /
• pp.26-39
• /
• 2016

Korea's main manufacturing industries, which have led its economy for the past three decades, are faced with a serious downturn and loss of competitive advantages due to the current economic depression, China's rise, and the drop of oil prices. Korean business firms must adopt the paradigm shift in their value strategies, along with a government-led industrial restructuring in order to gain sustainable competitive advantages. Business firms allocate their limited resources between value creation and value appropriation, however, what effect does strategic emphasis on value creation versus value appropriation have on a business firm's financial performance? This paper empirically addresses this issue by examining the effect of shifts in strategic emphasis on stock return. Furthermore, this study examines appropriate choices of strategic emphasis to gain differential financial performance. The data set used in this regression analysis comes from the KISLINE database of NICE Information Service. The variables that form the basis of this analysis are stock return, ROA, and Strategic Emphasis [(advertising expenditures-R&D expenditures)/assets]. The interactive effect with situational factors regarding the firm and the type of technological environment in which the firm is operating was also analyzed. Our results show that investors acknowledge a shift of strategic emphasis as a sign of stock valuation. In comparison to US, Korean business firms have weak value creation capabilities in high-technology industries, and weak value appropriation capabilities in low-technology industries. This proves Korean firms are fast followers in the global market. Our findings suggest that Korean firms have to adopt a balanced value strategy, nurturing value creation and developing value appropriation for overcoming the current economic downturn and becoming a first mover in the dawn of "Industry 4.0."

• 한국정보시스템학회지:정보시스템연구
• /
• 제16권1호
• /
• pp.135-158
• /
• 2007

The purpose of this research is to identify multidimensional motivation factors that determine the piracy of copyrighted digital music. The model is based on TPB(theory of planned behavior) as well as other models in consumer behavior. An empirical study resulted in the following findings. first Both individual's attitude toward music piracy and individual's perceived behavior control have positive impacts on the individual's behavioral intention of piracy. It turned out that perceived behavior control has a stronger impact on behavioral intention than attitude does. Second, the level of individual's moral judgment has negative impacts on both the attitude and behavioral intention toward music piracy. Third, individual's experience in music piracy positively affects the attitude, but does not directly or indirectly affect the behavior intention. Fourth, an economic gain from music piracy is not a significant factor in determining both attitude and behavioral intention. Fifth, the risk of being prosecuted for music piracy is a major factor in determining one's attitude, although the risk is not significant enough to change one's behavioral intention. This research found that individuals' intention to pirate digital music is mainly affected by the moral and ethical standards of the individuals and by the extra resources and abilities they possess. Such factors as economic gain and law enforcement were not significant enough to alter one's behavioral intention. This research is significant in that it established a behavioral model to understand the piracy of copyrighted digital music and that it empirically tested the model with Internet users in Korea. This is one of the first empirical studies in Korea to touch such ethically and perhaps politically sensitive issues as online music piracy.

• 한국초지조사료학회지
• /
• 제33권1호
• /
• pp.52-57
• /
• 2013

본 연구는 사슴의 조사료 원으로 엘크사슴에 대한 청보리 사일리지 급여가 사슴의 사료섭취량, 체중변화 및 경제성에 미치는 영향을 구명하기 위하여 실시하였다. 엘크사슴 21두를 공시하여 건초구, 청보리 사일리지구 및 건초+청보리 사일리지구로 나누어 농후사료를 3.7 kg 정량급여 하고 조사료는 자유채식 시켰으며, 그 결과는 다음과 같다. 엘크사슴의 일당증체량은 건초구, 청보리 사일리지구 및 건초+청보리 사일리지구 혼합구가 각각 0.26, 0.36 및 0.44 kg으로 건초+청보리 혼합구가 가장 높았고, 엘크사슴의 청보리 사일리지 일일섭취량은 6.25~9.00 kg (풍건) 범위였으며, DM 섭취량은 건초구, 건초+청보리 사일리지 혼합구 및 청보리 사일리지 순으로 높은 경향을 보였다. 녹용 생산량은 건초구, 청보리 사일리지구 및 건초+청보리 사일리지구가 각각 8,037, 7,713 및 8,585 g으로 건초+청보리 사일리지 혼합구가 가장 많았다. 3개 처리구간 일당증체량, 녹용생산량 및 사료섭취량은 사슴의 개체차가 심하여 통계적으로 유의성은 인정되지 않았지만(p>0.05) 증체량 및 녹용산량은 증가하는 경향을 보였다. 경제성 분석에서는 건초+청보리 사일리지 혼합구가 건초 및 청보리 사일리지 단독급여구보다 소득지수가 29~43% 높게 나타났다. 이상의 결과를 종합적으로 고려할 때 사슴의 조사료 원으로 청보리 사일리지는 기호성에서 건초를 대체할 만큼의 섭취량을 가지므로 이용가능성이 있었으며, 조사료 원으로 연중 공급이 가능하고, 경제적인 측면에서도 건초보다 유리하여 농가에서 사슴의 조사료 원으로 사용이 가능할 것으로 사료된다. 또한 청보리 사일리지 급여 시에는 청보리 사일리지 단독 급여보다는 청보리와 건초를 각각 50%씩 혼합 급여하는 것이 일당증체량, 증체, 녹용생산량 및 경제성에서 가장 바람직한 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제18권2호
• /
• pp.209-213
• /
• 2005

This study was conducted to determine the optimum substitution level of dried leftover food (DLF) in formula feed for Hanwoo (Korean Native Cattle) steers. A total of forty growing steers were assigned to 5 treatments based on substitution level of DLF (at 0, 25, 50, 75 and 100% level of formula feed). The experiment was carried out with growing steers from 6 months of age to 24 months of age. Average daily gain (ADG) was not affected by DLF substitution level up to 75% of formula feed. However ADG decreased at 100% substitution level. Daily feed intakes were similar among treatments but the amount of feed per 1 kg gain increased with increasing substitution level of DLF. Dressing percentage was around 62% in all treatments without any significant differences. Proportion of quality beef higher than grade 1 was the greatest from animals fed 25% substitution level of DLF. Economic efficiency for Hanwoo steer operator was the highest with 50% substitution level of DLF.