• Title/Summary/Keyword: Losses

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Semantic Segmentation for Roof Extraction using Official Buildings Information (건물 통합 정보를 이용한 지붕 추출 의미론적 분류)

  • Youm, Sungkwan;Lee, Heekwon;Shin, Kwang-Seong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.10a
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    • pp.582-583
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    • 2021
  • As the production of new and renewable energy such as solar and wind power has diversified, microgrid systems that can simultaneously produce and consume have been introduced. . In general, a decrease in electricity prices through solar power is expected in summer, so producer protection is required. In this paper, we propose a transparent and safe gift power transaction system between users using blockchain in a microgrid environment. A futures is simply a contract in which the buyer is obligated to buy electricity or the seller is obliged to sell electricity at a fixed price and a predetermined futures price. This system proposes a futures trading algorithm that searches for futures prices and concludes power transactions with automated operations without user intervention by using a smart contract, a reliable executable code within the blockchain network. If a power producer thinks that the price during the peak production period (Hajj) is likely to decrease during production planning, it sells futures first in the futures market and buys back futures during the peak production period (Haj) to make a profit in the spot market. losses can be compensated. In addition, if there is a risk that the price of electricity will rise when a sales contract is concluded, a broker can compensate for a loss in the spot market by first buying futures in the futures market and liquidating futures when the sales contract is fulfilled.

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Design and Implementation of Ethereum-based Future Power Trading System (이더리움 기반의 선물(Future) 전력 거래 시스템 설계)

  • Youm, Sungkwan;Lee, Heekwon;Shin, Kwang-Seong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.10a
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    • pp.584-585
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    • 2021
  • As the production of new and renewable energy such as solar and wind power has diversified, microgrid systems that can simultaneously produce and consume have been introduced. In general, a decrease in electricity prices through solar power is expected in summer, so producer protection is required. In this paper, we propose a transparent and safe gift power transaction system between users using blockchain in a microgrid environment. A futures is simply a contract in which the buyer is obligated to buy electricity or the seller is obliged to sell electricity at a fixed price and a predetermined futures price. This system proposes a futures trading algorithm that searches for futures prices and concludes power transactions with automated operations without user intervention by using a smart contract, a reliable executable code within the blockchain network. If a power producer thinks that the price during the peak production period is likely to decrease during production planning, it sells futures first in the futures market and buys back futures during the peak production period to make a profit in the spot market. losses can be compensated. In addition, if there is a risk that the price of electricity will rise when a sales contract is concluded, a broker can compensate for a loss in the spot market by first buying futures in the futures market and liquidating futures when the sales contract is fulfilled.

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Evaluation of Cavity Characterization Using Infrared Thermal Images (적외선 이미지를 이용한 지하공동 평가)

  • Jang, Byeong-Su;Kim, Young-Seok;Kim, Se-Won ;Choi, Hyun-Jun;Yoon, Hyung-Koo
    • Journal of the Korean Geotechnical Society
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    • v.39 no.7
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    • pp.69-76
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    • 2023
  • Cavity causes settlement and its remediation after an accident results in significant time and economic losses. This study aims to experimentally evaluate the prospect of using infrared camera to detect and measure underground subsidence. Emissivity is necessary to detect the energy emitted from an object and accurately assess temperature using an infrared camera. The emissivity in laboratory tests is fixed to evaluate a reasonable distance between the infrared camera and the object, and temperature values are assessed at various distances. In field experiments, the cavity of the field experiment is simulated using a PVC pipe with a diameter of 5 cm, artificially buried at depths of 5 and 25 cm from the surface. The infrared camera measurements are taken from 4 PM to 3 PM of the next day (a total of 23 h). The analysis included the time-series temperature distribution and the cooling rate index assessment, which represents the temperature change rate per unit of time. The results showed that various temperature trends are observed depending on the location of the subsidence. This study demonstrates that the infrared camera can be used to assess the condition of the subsurface.

High-resolution range and velocity estimation method based on generalized sinusoidal frequency modulation for high-speed underwater vehicle detection (고속 수중운동체 탐지를 위한 일반화된 사인파 주파수 변조 기반 고해상도 거리 및 속도 추정 기법)

  • Jinuk Park;Geunhwan Kim;Jongwon Seok;Jungpyo Hong
    • The Journal of the Acoustical Society of Korea
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    • v.42 no.4
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    • pp.320-328
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    • 2023
  • Underwater active target detection is vital for defense systems, requiring accurate detection and estimation of distance and velocity. Sequential transmission is necessary at each beam angle, but divided pulse length leads to range ambiguity. Multi-frequency transmission results in time-bandwidth product losses when bandwidth is divided. To overcome these problem, we propose a novel method using Generalized Sinusoidal Frequency Modulation (GSFM) for rapid target detection, enabling low-correlation pulses between subpulses without bandwidth division. The proposed method allows for rapid updates of the distance and velocity of target by employing GSFM with minimized pulse length. To evaluate our method, we simulated an underwater environment with reverberation. In the simulation, a linear frequency modulation of 0.05 s caused an average distance estimation error of 50 % and a velocity estimation error of 103 % due to limited frequency band. In contrast, GSFM accurately and quickly tracked targets with distance and velocity estimation errors of 10 % and 14 %, respectively, even with pulses of the same length. Furthermore, GSFM provided approximate azimuth information by transmitting highly orthogonal subpulses for each azimuth.

Evaluation of Soil Streptomyces spp. for the Biological Control of Fusarium Wilt Disease and Growth Promotion in Tomato and Banana

  • Praphat, Kawicha;Jariya, Nitayaros;Prakob, Saman;Sirikanya, Thaporn;Thanwanit, Thanyasiriwat;Khanitta, Somtrakoon;Kusavadee, Sangdee;Aphidech, Sangdee
    • The Plant Pathology Journal
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    • v.39 no.1
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    • pp.108-122
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    • 2023
  • Fusarium oxysporum f. sp. lycopersici (Fol) and Fusarium oxysporum f. sp. cubense (Foc), are the causal agent of Fusarium wilt disease of tomato and banana, respectively, and cause significant yield losses worldwide. A cost-effective measure, such as biological control agents, was used as an alternative method to control these pathogens. Therefore, in this study, six isolates of the Streptomyces-like colony were isolated from soils and their antagonistic activity against phytopathogenic fungi and plant growth-promoting (PGP) activity were assessed. The results showed that these isolates could inhibit the mycelial growth of Fol and Foc. Among them, isolate STRM304 showed the highest percentage of mycelial growth reduction and broad-spectrum antagonistic activity against all tested fungi. In the pot experiment study, the culture filtrate of isolates STRM103 and STRM104 significantly decreased disease severity and symptoms in Fol inoculated plants. Similarly, the culture filtrate of the STRM304 isolate significantly reduced the severity of the disease and symptoms of the disease in Foc inoculated plants. The PGP activity test presents PGP activities, such as indole acetic acid production, phosphate solubilization, starch hydrolysis, lignin hydrolysis, and cellulase activity. Interestingly, the application of the culture filtrate from all isolates increased the percentage of tomato seed germination and stimulated the growth of tomato plants and banana seedlings, increasing the elongation of the shoot and the root and shoot and root weight compared to the control treatment. Therefore, the isolate STRM103 and STRM104, and STRM304 could be used as biocontrol and PGP agents for tomato and banana, respectively, in sustainable agriculture.

Measurement of the Equivalent Resistance Coefficient for Multi-piers in Open Channel (개수로 다열기둥에 대한 상당저항계수의 측정)

  • Kwon, Kab Keun;Choi, Junwoo;Yoon, Sung Bum
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.6B
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    • pp.635-642
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    • 2008
  • The influence of unsubmerged resistance bodies in a channel turbulence flow on energy loss was investigated by hydraulic experiments. Square-shaped multi-piers were used for unsubmerged structure or rigid vegetation in an open channel. In experimental channel flows multi-piers were arranged in double or single row along the channel direction, and mean-concept uniform elevations were attained and measured with a set of discharges and channel slopes. Applying the experimental results to the Manning equation, the equivalent resistance coefficient n, which implicates flow resistance and energy loss due to bottom friction as well as drag, was evaluated with varying the interval of piers and the uniform water depth. And the experimentally evaluated n values were compared with the semi-theoretical formula of the equivalent resistance coefficient derived from momentum analysis including a drag interaction coefficient. From the comparisons it was found that the interaction effect of piers on flow resistance was significant for the overall energy losses in a channel flow. The n values decrease when the interval of piers in flow-direction is less than about 2.2 times of the pier width. And it was also found that the n values increase with the 2/3 power of water depth in the theoretical formula, since the drag interaction coefficient was found to be mostly dependent on the interval of piers.

Life-Cycle Cost Effective Optimal Seismic Retrofit and Maintenance Strategy of Bridge Structures - (II) Methodology for Life-Cycle Cost Analysis (교량의 생애주기비용 효율적인 최적 내진보강과 유지관리전략 - (II) 생애주기비용해석 방법론)

  • Lee, Kwang-Min;Cho, Hyo-Nam;Chung, Jee-Seung;An, Hyoung-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.6A
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    • pp.977-988
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    • 2006
  • The goal of this study is to develop a realistic methodology for determination of the Life-Cycle Cost (LCC)-effective optimal seismic retrofit and maintenance strategy of deteriorating bridges. The proposed methodology is based on the concept of minimum LCC which is expressed as the sum of present value of seismic retrofit costs, expected maintenance costs, and expected economic losses with the constraints such as design requirements and acceptable risk of death. The proposed methodology is applied to the LCC-effective optimal seismic retrofit and maintenance strategy of a steel bridge considered as a example bridge in the accompanying study, and various conditions such as corrosion environments and Average Daily Traffic Volumes (ADTVs) are considered to investigate the effects on total expected LCC. In addition, to verify the validity of the developed methodology, the results are compared with the existing methodology. From the numerical investigation, it may be positively expected that the proposed methodology can be effectively utilized as a practical tool for the decision-making of LCC-effective optimal seismic retrofit and maintenance strategy of deteriorating bridges.

Estimation of the Monetary Loss Scale of Low-income Freight Truck Owner under the Environmental Zone (환경지역 운영에 따른 영세 화물 차주의 경제적 손실규모 추정)

  • Choi, Kee Choo;Lee, Kyu Jin;Yi, Yong Ju
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.3D
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    • pp.247-254
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    • 2010
  • The positive effects of the air quality improvement policy have revealed sufficiently such as 3.3 trillion won of social benefits under the Environmental Zone in five years(K. Choi, 2009). In case of low-income freight truck owner, however, could be burdened with the requirement likes emission decreasing equipment. Eventually, restraint of running in the Environmental Zone would be affected their livelihood seriously. After estimating the scale of low-income freight truck owner for three alternatives with Road Freight Transport Center data, this study calculates decreased VKT to estimate the scale of monetary loss. In the result, decreased income amount of low-income freight truck owner under the restricted running estimated 6.1 trillion won during 5 years, quite exceeding 3.3 trillion won of the positive benefits as improving air quality, which means the necessity of immediate countermeasure. In other words, even though the governmental policy aimed benefits for the majority, the result implies that the total monetary losses of the minority could be exceed against the positives, therefore analysis should be considered carefully before the policy becomes effective.

Development of Hazard-Level Forecasting Model using Combined Method of Genetic Algorithm and Artificial Neural Network at Signalized Intersections (유전자 알고리즘과 신경망 이론의 결합에 의한 신호교차로 위험도 예측모형 개발에 관한 연구)

  • Kim, Joong-Hyo;Shin, Jae-Man;Park, Je-Jin;Ha, Tae-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.4D
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    • pp.351-360
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    • 2010
  • In 2010, the number of registered vehicles reached almost at 17.48 millions in Korea. This dramatic increase of vehicles influenced to increase the number of traffic accidents which is one of the serious social problems and also to soar the personal and economic losses in Korea. Through this research, an enhanced intersection hazard prediction model by combining Genetic Algorithm and Artificial Neural Network will be developed in order to obtain the important data for developing the countermeasures of traffic accidents and eventually to reduce the traffic accidents in Korea. Firstly, this research has investigated the influencing factors of road geometric features on the traffic volume of each approaching for the intersections where traffic accidents and congestions frequently take place and, a linear regression model of traffic accidents and traffic conflicts were developed by examining the relationship between traffic accidents and traffic conflicts through the statistical significance tests. Secondly, this research also developed an intersection hazard prediction model by combining Genetic Algorithm and Artificial Neural Network through applying the intersection traffic volume, the road geometric features and the specific variables of traffic conflicts. Lastly, this research found out that the developed model is better than the existed forecasting models in terms of the reliability and accuracy by comparing the actual number of traffic accidents and the predicted number of accidents from the developed model. In conclusion, it is expect that the cost/effectiveness of any traffic safety improvement projects can be maximized if this developed intersection hazard prediction model by combining Genetic Algorithm and Artificial Neural Network use practically at field in the future.

An Examination of the Effectiveness of Crisis Response Strategies for Repairing Competence and Integrity Violations

  • Sung, Yen-yi;Lee, Han-joon;Park, Jong-chul
    • Asia Marketing Journal
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    • v.15 no.1
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    • pp.129-154
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    • 2013
  • Product-harm crises, which are connected to defective or dangerous products, are perceived as the most common threats to a company. Product harm crises can distort long standing favorable equality perceptions, tarnish a company's reputation, cause major revenue and market-share losses, lead to costly product recalls, and devastate a carefully nurtured brand equity. However, in spite of the devastating impact of product-harm crises, little systematic research exists to asses its marketing consequences. So, the purpose of this study is to investigate how Koreans react to the crisis response in the aftermath of different crises(competence violation vs. integrity violation) and inspire additional research in crisis communication. This study has three main findings which run counter to the assumptions of Kim et al.(2007). Namely, the current study expands on the research of Kim et al. (2004, 2007) by examining how companies repair customers' trust and corporate attitude after crises. Different from previous studies, this study assumes that apology for an integrity-based crisis is the most appropriate way to repair consumer trust and corporate attitude. As for competence-based crisis, similarly, apology for competence-based crisis can be more successful repairing consumer trust and corporate attitude. Concerning silence strategy, remaining silent dose not admit or deny guilt right away, but instead of asking the perceiver to withhold judgment, suggesting that, silence could be expected to be superior to apology but inferior to denial. Finally, apology for competence violation will be expected to bemore effective than apology for integrity violation. Research conceptual model was as follows: According to the results, apology is found to be the most effective strategy to repair corporate attitude no matter the crisis is perceived as a violation of competence or integrity. Second, company may consider keeping silent as a desirable response because they does not admit nor deny responsibility but ask the public to withhold judgment. However, the result of this study shows that, in the overall crisis situations, silence strategy did not differ significantly from the denial strategy, which suggested that the public wants explanation instead of uncertainty. Third, there was the interaction effect between crisis type and crisis response strategies. In this study, apology is more effective for the competence violated situation in terms of regaining consumer trust and repairing their attitude toward company, while the apology's effectiveness is lower for the integrity-violated situation. More specifically, when the crisis is perceived due to company's lack of ability(competence violation), consumer's trust belief and attitude toward the company is more easily to repair when the company issued a sincere apology. Damaged product is perceived less intentional so participants are more likely to give the company second chance when they apology to the public. By contrast, exaggerated advertisement(integrity violation) is perceived intentionally and thus makes participants angrier toward the accused company. Although apology is perceived as the most effective strategy, when issuing apology, it also means the company admitted their intention. Therefore, in this kind of crisis situation, trust repair needs not only a sincere apology but additional efforts.

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