• Geomechanics and Engineering
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• v.34 no.3
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• pp.267-284
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• 2023

Landslides are one of the most dangerous phenomena and natural disasters. Landslides cause many human and financial losses in most parts of the world, especially in mountainous areas. Due to the climatic conditions and topography, people in the northern and western regions of Iran live with the risk of landslides. One of the measures that can effectively reduce the possible risks of landslides and their crisis management is to identify potential areas prone to landslides through multi-criteria modeling approach. This research aims to model landslide potential area in the Oshvand watershed using a support vector machine algorithm. For this purpose, evidence maps of seven effective factors in the occurrence of landslides namely slope, slope direction, height, distance from the fault, the density of waterways, rainfall, and geology, were prepared. The maps were generated and weighted using the continuous fuzzification method and logistic functions, resulting values in zero and one range as weights. The weighted maps were then combined using the support vector machine algorithm. For the training and testing of the machine, 81 slippery ground points and 81 non-sliding points were used. Modeling procedure was done using four linear, polynomial, Gaussian, and sigmoid kernels. The efficiency of each model was compared using the area under the receiver operating characteristic curve; the root means square error, and the correlation coefficient . Finally, the landslide potential model that was obtained using Gaussian's kernel was selected as the best one for susceptibility of landslides in the Oshvand watershed.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.32-41
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• 2017

Accidents on offshore oil and gas platforms (OOGPs) usually cause serious fatalities and financial losses considering demanding environment platforms locate and complex topsides structure platforms own. Evacuation planning on platforms is usually challenging. The computational tool is a good choice to plan evacuation by emergency simulation. However, the complex structure of platforms and varied evacuation behaviors usually weaken the advantages of computational simulation. Therefore, this study developed a simulation model for OOGPs to evaluate different evacuation plans to improve evacuation performance by integrating building information modeling (BIM) and agent-based model (ABM). The developed model consists of four parts: evacuation model input, simulation environment modeling, agent definition, and simulation and comparison. Necessary platform information is extracted from BIM and then used to model simulation environment by integrating matrix model and network model. During agent definition, in addition to basic characteristics, environment sensing and dynamic escape path planning functions are also developed to improve simulation performance. An example OOGP BIM topsides with different emergent scenarios is used to illustrate the developed model. The results showed that the developed model can well simulate evacuation on OOGPs and improve evacuation performance. The developed model was also suggested to be applied to other industries such as the architecture, engineering, and construction industry.

• Korea Trade Review
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• v.46 no.2
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• pp.19-38
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• 2021

This study aims to analyze the foreign asset leverage effect on Korean oil & gas companies' foreign profits and to maintain the appropriate foreign asset volume for reducing exchange risk. For a long time, large Korean companies, including oil companies, overheld foreign currency liabilities. For this reason, most large companies have been burdened to hedge exchange risk and this excess limit holding deteriorated total profit and reduced foreign currency asset management efficiency. Our paper proceeds in presenting a three-stage analysis considering diversified exchange risk factors through estimation on transformation of foreign transactions a/c including annual trends of foreign asset and industry specifics. We also supplement incomplete the estimation method through a practical hedging case investigation. Our research parts are differentiated on the analyzing four periods considering period-specifics The FER value of the oil firms ranged from -0.3 to +2.3 over the entire period. The results of the FER Value are volatile and irregular; those results do not represent the industry standard comparative index. The Korean oil firms are over the credit limit without accurate prediction and finance high interest rate funds from foreign-owned banks on the basis on a biased relationship. Since the IMF crisis, liabilities of global firms have decreased. Above all, oil firms need to finance a minimum limit without opportunity losses on the demand forecast and prepare for uncertainty in the market. To reduce exchange risk from the over-the-limit position, we must consider factors that affect the corporate exchange risk on the entire business process, including the contract phase.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.17 no.4
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• pp.221-228
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• 2024

Predicting insurance claims is a key task for insurance companies to manage risks and maintain financial stability. Accurate insurance claim predictions enable insurers to set appropriate premiums, reduce unexpected losses, and improve the quality of customer service. This study aims to enhance the performance of insurance claim prediction models by applying ensemble learning techniques. The predictive performance of models such as Random Forest, Gradient Boosting Machine (GBM), XGBoost, Stacking, and the proposed Dynamic Weighted Ensemble (DWE) model were compared and analyzed. Model performance was evaluated using Mean Absolute Error (MAE), Mean Squared Error (MSE), and the Coefficient of Determination (R²). Experimental results showed that the DWE model outperformed others in terms of evaluation metrics, achieving optimal predictive performance by combining the prediction results of Random Forest, XGBoost, LR, and LightGBM. This study demonstrates that ensemble learning techniques are effective in improving the accuracy of insurance claim predictions and suggests the potential utilization of AI-based predictive models in the insurance industry.

• Clinical and Experimental Vaccine Research
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• v.11 no.1
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• pp.1-11
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• 2022

Purpose: Lumpy skin disease (LSD) is a highly contagious and economically important viral infection of cattle, which leads to financial losses in the livestock industry of affected countries. Vaccination is the most effective control measure to prevent the disease. Heterologous sheep pox (SP) vaccine was used against LSD in Turkey. In this research, it was aimed to adapt SP Bakırköy vaccine strain attenuated in lamb kidney cells to Madin-Darby bovine kidney (MDBK) cells to provide better protection than commercial SP vaccine in cattle. Materials and Methods: To evaluate safety and efficacy of vaccines, while animals were immunized with 10 doses (10^4.75 50% tissue culture infectious dose [TCID₅₀]) and 5 doses of SP vaccine (10⁴ TCID₅₀) produced in MDBK cells, others were immunized with commercial Penpox-M vaccine (10^3.9 TCID₅₀). Two cattle were kept as unvaccinated. At day 31 post-vaccination, all animals were challenged with the virulent LSD virus. Blood and swab samples were taken on certain days post-inoculation. Logarithmic differences challenge virus titers between vaccinated and unvaccinated animals were calculated. Results: The clinical sign was not observed in animals immunized with 10 doses of SP vaccine. The differences between the animals immunized with SP vaccine and control group was less than log 2.5 and the viremia occurred in immunized animals. The difference in titer was higher than log 2.5 in animals immunized with the Penpox-M, and viremia did not occur. Conclusion: SP vaccine strain propagated in MDBK cells and can be used for immunization to prevent LSD infections. However, SP vaccine strain propagated in MDBK showed poor protection as compared to Penpox-M.

• Korean Journal of Construction Engineering and Management
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• v.15 no.5
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• pp.94-102
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• 2014

This study analyzes necessity of expanding construction insurance and estimates required budget. Construction insurance is obliged by National Contract Law and Local Contract Law to protect projet owners and contractors from any unexpected construction risk such as financial losses in construction process. Currently the contracts of design-build and alternate-bid projects as well as PQ project, which are greater than 20 billion won, require the contractors to provide construction insurances in Korea. Insurance premiums are borne by the public project owner. Those contractors whose contract volume is less than 20 billion won burden all risks of projects at their cost. This causes equity problem. Because small-and-medium contractors are discriminated against large contractors since insurance-obliged projects are performed by large contractors and insurance premiums are borne by the public project owner. On the other hands, in all engineering projects, regardless of volume, insurance premiums are borne by the project owner. Therefore current regulation has to be improved, by expanding to all public projects. The average ratio of unobliged projects is 46%, in recent 3 years, prime cost of insurance companies is estimated 0.2%. Moreover considering risks of each construction type, prime cost of unobliged works is estimated as 0.13%. Hence additional necessary budget is estimated to be 2.09 billion won if total volume of public work is 3.5 trillion won. And 2.39 billion won is derived if total volume of public projects is 4 trillion won.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.2
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• pp.141-154
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• 2015

In general, conventional criticality analysis for spent fuel transport/storage systems have been performed based on the assumption of fresh fuel concerning the potential uncertainties from number density calculations of actinide nuclides and fission products in spent fuel. However, these evaluation methods cause financial losses due to an excessive criticality margin. In order to overcome this disadvantage, many studies have recently been conducted to design and commercialize a transportation and storage cask applied to the Burnup Credit (BUC). This study conducted an assessment to ensure criticality safety for reactor operating parameters, axial burn-up profiles and misload accident conditions, which are the factors that are likely to affect criticality safety when the BUC is applied to the dual-purpose cask under development at the KOrea RADioactive waste agency (KORAD). As a result, it was found that criticality resulting from specific power, changed substantially and relied on conditions of low enrichment and high burn-up. Considering the end effect in the case of high burn-up produced a positive-definite result. In particular, the increment of maximum effective multiplication factors due to misloading was 0.18467, confirming that misload is a factor that must be taken into account when applying the BUC. The results of this study may therefore be utilized as references in developing technologies to apply the BUC to domestic models and operational procedures or preventing any misload accidents during the process of spent fuel loading.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.7
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• pp.1044-1052
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• 2015

The aim of this modelling study was to investigate the effect of large herd size (and land areas) on walking distances and milking interval (MI), and their impact on milk yield and economic penalties when 50% of the total diets were provided from home grown feed either as pasture or grazeable complementary forage rotation (CFR) in an automatic milking system (AMS). Twelve scenarios consisting of 3 AMS herds (400, 600, 800 cows), 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as 'moderate'; optimum pasture utilisation of 19.7 t DM/ha, termed as 'high') and 2 rates of incorporation of grazeable complementary forage system (CFS: 0, 30%; CFS = 65% farm is CFR and 35% of farm is pasture) were investigated. Walking distances, energy loss due to walking, MI, reduction in milk yield and income loss were calculated for each treatment based on information available in the literature. With moderate pasture utilisation and 0% CFR, increasing the herd size from 400 to 800 cows resulted in an increase in total walking distances between the parlour and the paddock from 3.5 to 6.3 km. Consequently, MI increased from 15.2 to 16.4 h with increased herd size from 400 to 800 cows. High pasture utilisation (allowing for an increased stocking density) reduced the total walking distances up to 1 km, thus reduced the MI by up to 0.5 h compared to the moderate pasture, 800 cow herd combination. The high pasture utilisation combined with 30% of the farm in CFR in the farm reduced the total walking distances by up to 1.7 km and MI by up to 0.8 h compared to the moderate pasture and 800 cow herd combination. For moderate pasture utilisation, increasing the herd size from 400 to 800 cows resulted in more dramatic milk yield penalty as yield increasing from c.f. 2.6 and 5.1 kg/cow/d respectively, which incurred a loss of up to $AU 1.9/cow/d. Milk yield losses of 0.61 kg and 0.25 kg for every km increase in total walking distance (voluntary return trip from parlour to paddock) and every one hour increase in MI, respectively. The high pasture utilisation combined with 30% of the farm in CFR in the farm increased milk yield by up to 1.5 kg/cow/d, thereby reducing loss by up to $0.5/cow/d (c.f. the moderate pasture and 800 cow herd scenario). Thus, it was concluded that the successful integration of grazeable CFS with pasture has the potential to improve financial performance compared to the pasture only, large herd, AMS.

• Information Systems Review
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• v.9 no.1
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• pp.105-120
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• 2007

With the fast development of the Internet and the increasing dependence on information infrastructures, companies are faced with various information security threats such as information leakages, modifications, and information breaches. South Korea is one of the leading countries in the Internet usage, but is ranked relatively low when it comes to information security. In fact, many Korean firms have suffered financial losses and damaged corporate images from the information security breaches. However, because of the difficulties in quantifying the costs of the information security breaches, Korean companies tend to delay their investment decisions on information security. The purpose of this study is to measure the cost of information security breach and the economic value of security investment using the event study methodology. Our results show that the announcement of an information security breach negatively influenced the market value of the corresponding company. The effect was statistically significant at the significance level of p=0.05. The breached companies lose, on average, 0.86% of their market values on the day of the announcement - an average loss in market capitalization of $55 million. On the other hand, the investment on information security had no effect on the stock price or the market value of the firm.

• Korean Journal of Hospice Care
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• v.2 no.1
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• pp.87-111
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• 2002

The hospice activities in Korea have still stood in the premature stage, although the contemporary hospice program, which professionally accommodates terminally ill patients, appeared in the history 35 years ago. Especially, the availability of the facility hospice is not only poor in number, but also lack of a guideline for the conduct of the facility. Saemmul Hospice has keenly felt the necessity of more facility hospices and has interchanged experiences and informations with people interested in hospice. However, the number of facilities has fallen short of one's expectations, and many problems have been revealed in order to maintain the operation. This paper was written in order to improve these atmospheres and to help more terminally ill cancer patients properly. This paper clarifies in detail the principle of management, the method of practice in each departments of Saemmul Hospice, expected effects and supplemental items. We try to provide concrete and practical informations and to help extensively for all peoples who are to begin or currently working. 1.Facility: It secures, maintain, and manage the hospice environment for all around care of patients effectively. 2.Education and Volunteer: It trains and manages hospice volunteers devoted to hospice. 3.Financial: It manages donation by healthy soul with an effective method. 4.Administration and Organization: It executes the administration efficiently and constitutes the organization to operate. 5.Medical and Nursing: It offers the maximum professional supports to a hospital. 6.Medicine and alternative medicine: It improves the quality of life of patients by medical and pharmaceutical approach and by other possible methods available. 7.Nutrition: It helps patients to have diets in accord with the order of the creation. 8.Belief: It offers spiritual care which allows the profound relationship with God. 9. Funeral ceremonies: Funeral ceremonies may heal grieves of families faced with their deaths. 10. Bereaved families: It supports the families after the deaths of patients. 11.Reception and consultation: It seeks to help the patients who meet the purposes for which Saemmul Hospice is established. 12.Publication: It allows publicity activities for Saemmul Hospice. Facility hospice programs are able to overcome the disadvantages that the other type of the hospice possess, like as the economic burdens of the families, and the patients' losses of comforts of home after being transferred to a hospital. Facility hospice can provide home atmosphere with professional manpower and facilities like hospital to the patients. Therefore, it can also improve patients' qualities of life and make them comfortable death. We anticipate that the hospice program in Korea would be more active to let more people be indebted to maintain the nobel human dignity and to cross beautifully in the most painful process of dying in the journey of their lives.