• 제목/요약/키워드: Spread Impact

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Application of multi-objective genetic algorithm for waste load allocation in a river basin (오염부하량 할당에 있어서 다목적 유전알고리즘의 적용 방법에 관한 연구)

  • Cho, Jae-Heon
    • Journal of Environmental Impact Assessment
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    • v.22 no.6
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    • pp.713-724
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    • 2013
  • In terms of waste load allocation, inequality of waste load discharge must be considered as well as economic aspects such as minimization of waste load abatement. The inequality of waste load discharge between areas was calculated with Gini coefficient and was included as one of the objective functions of the multi-objective waste load allocation. In the past, multi-objective functions were usually weighted and then transformed into a single objective optimization problem. Recently, however, due to the difficulties of applying weighting factors, multi-objective genetic algorithms (GA) that require only one execution for optimization is being developed. This study analyzes multi-objective waste load allocation using NSGA-II-aJG that applies Pareto-dominance theory and it's adaptation of jumping gene. A sensitivity analysis was conducted for the parameters that have significant influence on the solution of multi-objective GA such as population size, crossover probability, mutation probability, length of chromosome, jumping gene probability. Among the five aforementioned parameters, mutation probability turned out to be the most sensitive parameter towards the objective function of minimization of waste load abatement. Spacing and maximum spread are indexes that show the distribution and range of optimum solution, and these two values were the optimum or near optimal values for the selected parameter values to minimize waste load abatement.

An Analysis of the Impact of Coronavirus Disease (COVID-19) on the Korean Beef Cattle Market and Farm Labor Demand for Korean Beef Cattle (코로나19가 한육우 시장 및 한육우 농가 인력수요에 미치는 영향분석)

  • Kim, In-Seck
    • Korean Journal of Organic Agriculture
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    • v.28 no.2
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    • pp.171-188
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    • 2020
  • The Coronavirus disease (COVID-19), first identified in China in December 2019, has widely spread worldwide and is an ongoing pandemic. It is expected that the ripple effect of COVID-19 on the global economy including the agricultural sector will increase substantially if not properly controlled shortly. This study examines the potential impact of COVID-19 on the Korean beef cattle sector and farm labor demand for Korean beef cattle using a dynamic partial equilibrium model. The agricultural production value and farm labor demand for Korean beef cattle in the scenario assuming pessimistic GDP growth rate (-1.2% in 2020) with no direct supply shocks fell by up to 4.00% and 0.67%, respectively, compared to the baseline which represents the future without COVID-19 outbreak. On the other hand, the agricultural production value and farm labor demand for Korean beef cattle in the scenario assuming both pessimistic GDP growth rate and supply shocks (-12.7% beef imports and + 2.4% feed cost in 2020) increased by up to 12.08% and 1.99%, respectively, compared to the baseline.

Environmental Assessment and Environment-Friendly Development in Mountainous Area in Constructing Photovoltaic Complex (태양광단지의 산지입지에 따른 환경성평가 및 환경친화적 개발 방안)

  • Ahn, Sewoong;Joo, Hyun Soo;Lee, Hi Sun
    • Journal of Environmental Impact Assessment
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    • v.20 no.2
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    • pp.141-150
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    • 2011
  • The construction of photovoltaic complex in mountainous area is quickly increasing recently so that the environment assessment in constructing photovoltain complex in mountainous area was performed by comparison of $CO_{2{\cdot}}$ reduction and forest damage. The case studies for environmental value assessment, which construct photovoltaic complex in mountainous area, show that the losses of around 5.1billion won arise during 15 years. The government's official target for spreading photovoltaic energy until year 2030 can be satisfied when considering other alternative sites, improvement of technology and the alternative sites of an idle space of a building or a disused site, etc, except an undeveloped mountainous area. The construction of photovoltaic complex in mountainous area can cause the great damage to the environment, especially undeveloped mountainous area such as Baekdudaegan, and this defeat its own purpose of using photovoltaic energy. Therefore, the spread of photovoltaic complex through the additional damage of forest should be sublated.

Application of the Cost-Distance Measures for Designating Zone Boundaries in DIF Zoning

  • Choi, Joon Young;Choei, Nae Young
    • Journal of Korean Society for Geospatial Information Science
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    • v.24 no.2
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    • pp.3-13
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    • 2016
  • The development impact fee (DIF) zoning is used to adequately provide the pre-planned urban infrastructures in those urban and regional sectors where significant urban sprawl has already taken place followed by the rapid population growth. The infrastructure installation fees are levied to those landowners whose properties belong to the DIF zone in which they enjoy the direct benefits that accrue from the installed infrastructures. While the law is deemed to be equitable in that the actual beneficiaries pay for their benefits, it is required to designate the zone boundaries accurately and consistently since they are the very dividers that differentiate the legitimate fee-payers and the free-riders. This study, especially, tries to test a seemingly advanced alternative, so-called the cost-weighted distance measure, as a potential candidate to replace the current air-distance measures to designate the zone boundaries. The statistics indicate that the coefficient of variation for major indices spread from 11.75 to 35.6 in the case of the latter method, it only ranges from 0.21 to 0.76 in the case of the former. The zonal outcomes also show much higher consistency in their shapes. It is hoped, in this context, that the study findings could possibly be adopted in the future research efforts expected soon to amend and improve the current DIF zoning law.

Effect of Flame Spray Distance on Particle Behavior and Morphological Characteristics of $Ni_{20}Cr$ Coated Layers (화염용사 거리에 따른 입자의 거동 및 $Ni_{20}Cr$ 코팅층 특성 연구)

  • Lee, Jae Bin;Shin, Dong Hwan;Lee, Seong Hyuk
    • Journal of ILASS-Korea
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    • v.17 no.3
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    • pp.128-133
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    • 2012
  • The present study aims to examine the influence of flame spray distance on the thermal behavior of micro-metal particles and the morphological characteristics of $Ni_{20}Cr$ layers coated on the preheated SCM415 substrates by using the conventional flame spray system. Commercially available nickel-based $Ni_{20}Cr$ particles with a mean diameter of $45{\mu}m$ were used. In addition, CFD simulations using a commercial code (FLUENT ver. 6.3.26) were conducted to estimate temperature and velocity distributions of the continuous and discrete phases before impact on the substrate. From FE-SEM images of coated layers on the substrates, it was observed that as the spray distance decreased, the metal particle morphology showed splash-like patterns and such a short stretch shape, resulting from higher particle momentums and the impact of partially melted particles. Moreover, it was found that the spray distance should be considered as one of important parameters in controlling the porosity and the adhesion strength.

Who Reads Indian and Chinese LIS Articles on Mendeley? Scoping and Comparing User Categories Through Altmetrics

  • Vysakh, C.;Babu, H. Rajendra
    • Journal of Information Science Theory and Practice
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    • v.9 no.4
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    • pp.75-83
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    • 2021
  • Mendeley reader count is good evidence of the early impact of scientific output since it appears before citations. This paper aims to scope and compare Mendeley readers of Library and Information Science (LIS) articles published from India and China. Mendeley readership data for the highly cited 1,000 articles in Web of Science are extracted using Webometric Analyst for both countries and are analysed using Excel and SPSS. The findings reveal that LIS articles that are published from China got more readers as compared to LIS articles published from India with an excess of 97 readers per paper on Mendeley. The occupational status of readers tells that PhD students are the top readers for both the countries' publications, followed by masters students. Discipline-wise readership shows that readers were spread across 29 different fields, with the highest readers from business, management and accounting, followed by computer science for both countries' publications. Location-wise readership depicts that the top engaged readers are from the United States for both the countries' publications. Finally, the study reports a positive association between citations and Mendeley bookmarks, justifying that Mendeley readership can be used to measure the early research impact of LIS scholarship in both countries.

The Relationship between Hospital Service Quality and Customer Satisfaction: An Empirical Study from Vietnam

  • NGUYEN, Ngoc Mai;DUONG, Thi Thu Ly
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.12
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    • pp.553-561
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    • 2021
  • Health services in developing countries are increasingly focused on satisfying the needs of customers. During the COVID-19 pandemic, many patients have anxiety when going to hospitals for medical treatment. The pressures brought by the pandemic have overwhelmed the hospital system in Vietnam. This has caused the quality of service at these hospitals to decrease because they have focused on the goal of preventing the spread of the virus. Therefore, hospitals, especially private hospitals, need many solutions to improve the quality of their services. This study evaluated the impact of these factors on hospital service quality, as well as the influence of customer service quality on patient satisfaction. The survey was conducted from January 2021 to September 2021 and data was collected directly from 539 patients at Van Phuc Hospital 1. The results show that 4 factors affect the service quality of the hospital, as well as the service quality affecting patient satisfaction, in which, the strongest impact on the service quality of the hospital is the service attitude and professional capacity of the medical team. In the context of the COVID-19 epidemic, this study implies that if the hospital service is good, the customers' peace of mind and satisfaction will be enhanced.

A Study on the Effects of Resident Participation in Energy Saving Activities (거주자 참여형 에너지 절감 활동 효과 연구 -S대학 기숙사 거주 학생을 대상으로 한 에너지피드백 활동을 중심으로-)

  • Jung, Hye-jin;Song, Hae
    • Journal of Climate Change Research
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    • v.9 no.3
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    • pp.253-261
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    • 2018
  • As user-involved energy saving activities have become important in recent years, many forms of energy feedback experiments have been conducted. We conducted a study to determine if energy feedback activities affect energy saving for students living in dormitories at a university in Seoul. In particular, smart plugs were used for efficient research and quantitative performance measurements, and the extent of the impact of competition and rewards on participant energy saving behavior was further analyzed. The main findings of this study are as follows. First, the power usage of groups using smart plugs was lower than that of those without them. Second, energy feedback delivered to smart plug users did not have a significant impact on reduction of electric power consumption. Third, competition and compensation strategies had additional effects in reducing power usage for smart plug users. As a result, methods to deliver energy feedback more effectively as ICT technologies develop and efficient energy activities using IoT technologies can be expected to spread widely in the future.

Are Patients with Asthma and Chronic Obstructive Pulmonary Disease Preferred Targets of COVID-19?

  • Bouazza, Belaid;Hadj-Said, Dihia;Pescatore, Karen A.;Chahed, Rachid
    • Tuberculosis and Respiratory Diseases
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    • v.84 no.1
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    • pp.22-34
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    • 2021
  • The coronavirus pandemic, known as coronavirus disease 2019 (COVID-19), is an infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus first identified in patients from Wuhan, China. Since December 2019, SARS-CoV-2 has spread swiftly around the world, infected more than 25 million people, and caused more than 800,000 deaths in 188 countries. Chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) appear to be risk factors for COVID-19, however, their prevalence remains controversial. In fact, studies in China reported lower rates of chronic respiratory conditions in patients with COVID-19 than in the general population, while the trend is reversed in the United States and Europe. Although the underlying molecular mechanisms of a possible interaction between COVID-19 and chronic respiratory diseases remain unknown, some observations can help to elucidate them. Indeed, physiological changes, immune response, or medications used against SARS-CoV-2 may have a greater impact on patients with chronic respiratory conditions already debilitated by chronic inflammation, dyspnea, and the use of immunosuppressant drugs like corticosteroids. In this review, we discuss importance and the impact of COVID-19 on asthma and COPD patients, the possible available treatments, and patient management during the pandemic.

The Contagion of Covid-19 Pandemic on The Volatilities of International Crude Oil Prices, Gold, Exchange Rates and Bitcoin

  • OZTURK, M. Busra Engin;CAVDAR, Seyma Caliskan
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.171-179
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    • 2021
  • In the international markets, financial variables can be volatile and may affect each other, especially in the crisis times. COVID-19, which began in China in 2019 and spread to many countries of the world, created a crisis not only in the global health system but also in the international financial markets and economy. The purpose of this study is to analyze the contagious effect of the COVID-19 pandemic on the volatility of selected financial variables such as Bitcoin, gold, oil price, and exchange rates and the connections between the volatilities of these variables during the pandemic. For this aim, we use the ARMA-EGARCH model to measure the impact of volatility and shocks. In other words, it is aimed to measure whether the impact of the shock on the financial variables of the contagiousness of the epidemic is also transmitted to the markets. The data was collected from secondary and daily data from September 2th 2019 to December 20th, 2020. It can be said that the findings obtained have statistically significant effects on the conditional variability of the variables. Therefore, there are findings that the shocks in the market are contaminated with each other.