• Journal of information and communication convergence engineering
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• v.20 no.2
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• pp.90-95
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• 2022

This paper proposes a method to find a tree with the maximum number of terminals that can be connected by a given length when numerous terminals distributed in a cluster form are given to the Euclidean plane R2 with several constraints. First constraint is that a given terminal is distributed in a cluster form, second is that a given length cannot connect all terminals in the tree, and third is that there is no curved connection between each terminal. This paper proposes a method to establish more efficient interconnections within terminals distributed in a cluster form by improving a randomly distributed memetic genetic algorithm. The construction of interconnections has been extensively used in design-related fields, from networking to architecture. Additionally, in real life, the construction of interconnections is mostly distributed in the form of clusters. Therefore, the heuristic algorithm proposed in this paper can be effectively utilized in real life and is expected to provide various cost savings.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.108.2-109
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• 2003

The Gyeonggi-do Agricultural Research and Extension Services has developed a web-site (www.epilove.com) in collaboration with EPINET to provide information on agricultural weather and rice disease and insect pest management in Gyeonggi-do. Weather information includes near real-time weather data monitored by automated weather stations (AWS) installed at rice paddy fields of 11 Agricultural Technology Centers (ATC) in Gyeonggi-do, and weekly weather forecast by Korea Meteorological Administration (KMA). Map images of hourly air temperature and rainfall are also generated at 309m x 309m resolution using hourly data obtained from AWS installed at 191 locations by KMA. Based on near real-time weather data from 11 ATC, hourly infection risks of rice blast, sheath blight, and bacterial grain rot for individual districts are estimated by disease forecasting models, BLAST, SHBLIGHT, and GRAINROT. Users can diagnose various diseases and insects of rice and find their information in detail by browsing thumbnail images of them. A database on agrochemicals is linked to the system for disease and insect diagnosis to help users search for appropriate agrochemicals to control diseases and insect pests.

• Nuclear Engineering and Technology
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• v.54 no.12
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• pp.4644-4651
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• 2022

Due to its short half-life, thoron gas has been assumed to have negligible health hazards on humans compared to radon. But, one of the decay products with a long half-life can make it to be transported to a long distance and to cause a severe internal dose through respiration. Since most commercial radon detectors can not discriminate thoron signals from radon signals, it is very common to overestimate radon doses which in turn result in biased estimation of lung cancer risk in epidemiological studies. Though some methods had been suggested to measure thoron and radon separately, they could not be used for real-time measurement because of CR-39 or LR-115. In this study, an effective method was suggested to measure radon and thoron separately from the free air. It was observed that the activity of thoron decreases exponentially due to delay time caused by a long pipe between two chambers. Therefore from two ion chambers apart in time, it was demonstrated that thoron and radon could be measured separately and simultaneously. We also developed a collimated alpha source and with this source and an SBD, we could convert the ion chamber reading to count rate in cps.

• Journal of Distribution Science
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• v.22 no.4
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• pp.91-104
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• 2024

Purpose: The study aims to assess the current status of domestic public food delivery apps and analyze the process through which sellers choose between private delivery apps and public delivery apps. This involves exploring strategiesto achieve the original purpose of public food delivery apps, which is to enhance the small business owners income and promote consumer welfare by preventing the monopoly of private food delivery apps. Research design, data and methodology: the research methodology is based on a model that introduces adjustments for non-economic effects, considering the preferences of multi-homing consumers, to more realistically reflect the benefits of sellers' choices. For data analysis, real business performance data from 'Daeguro', 'Meokkaebi', and 'Somunnan Shop' were used. Results: The study revealed that if the market share of public delivery apps within a specific region increases beyond a certain level, the benefits for small-business sellers also increase. This leads to the strategic advantage of simultaneously using both delivery apps. Furthermore, the results exhibit a tendency similar to real social phenomena. Conclusions: This analysis confirmed the role of public food delivery apps in the domestic delivery app market and presents policy recommendations, including application integration and the implementation of exclusive public interest functions, to effectively fulfill this role.

• Journal of applied mathematics & informatics
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• v.42 no.2
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• pp.257-281
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• 2024

In real life, a decision-maker can assign multiple values for pairwise comparison with a certain confidence level. Studies incorporating multi-choice parameters in multi-criteria decision-making methods are lacking in the literature. So, In this work, an extension of the Best-Worst Method (BWM) with multi-choice pairwise comparisons and multi-choice confidence parameters has been proposed. This work incorporates an extension to the original BWM with multi-choice uncertainty and confidence level. The BWM presumes the Decision-Maker to be fully confident about preference criteria vectors best to others & others to worst. In the proposed work, we consider uncertainty by giving decision-makers freedom to have multiple choices for preference comparison and having a corresponding confidence degree for each choice. This adds one more parameter corresponding to the degree of confidence of each choice to the already existing MCDM, i.e. multi-choice BWM and yields acceptable results similar to other studies. Also, the consistency ratio remained low within the acceptable range. Two real-life case studies are presented to validate our study on proposed models.

• Journal of Agricultural Extension & Community Development
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• v.5 no.1
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• pp.31-44
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• 1998

An environmental problem is the important issue of mankind. It should be treated main discourse in our period. There are many assertions related to environment but they are not to be clearly classified because of miscellaneous paradigm. It is possible to classify into two category on the basis of human attitude toward nature and environmental problem. One of them is anthropocentrism and the other is ecocentrism. This classification is helpful to understand various environmental discourses. Owing to different paradigm approach, anthropocentrism and ecocentrism have different concept for environmental problem. Anthropocentrism is powerful to the real life in behalf of economic rationalism. But ecocentrism is important for the only settlement of environmental problem in ecocentric perspectives. Therefore a new scheme for environmental problem solving is necessary through combining the merits of anthropocentrism and ecocentrism.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.167-172
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• 2011

Generally, the analysis of railroad wear data is most effective method for the efficient railway maintenance. The wear of railway track affects loss of rough ride, noise or vibration of train and traveling safety. Moreover as the track is worn away, this promotes destruction of structural mechanism of rail track which can bring about increasing of rail track maintenance cost drastically. For this reason, it is very important and interested research subject to design railway track structure and to analyse train movement mechanism based on systematic analysis of the reasons causing rail wear possible in real field. In this research, for the efficient maintenance, Life Cycle Performance of rail track and maintenance characteristics are computed considering some track components such as track type, contracting type, sleeper type and roadbed type. Time - Wear probabilistic distribution relationship as well as multiple regression analysis based on time, curvature and wear data are computed to predict the service life remainder of railway track and to be adapted to safety assessment.

• Journal of Welding and Joining
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• v.11 no.4
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• pp.112-124
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• 1993

It has been reported that fatigue damage sometimes occurred at the stress concentrated and dynamic loaded structural members of bulk carrier. In this paper, studies on fatigue strength of hull structures are reviewed, and the program for evaluating fatigue strength is developed. And the fatigue crack initiation and propagation on the end part of cargo hold frame of bulk carrier were calculated by FEM stress analysis and the fatigue strength evaluation program. These method can be applied not only to the crack initiation life but also to crack propagation life for the hull structural members at the hull design stage and be effective as the guideline to prevent the crack initiation or to estimate the fatigue strength for repairing of the fatigue damaged structures of real ships.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.195-195
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• 2004

To discover germ cell-specific transcripts, we prepared a cDNA library from adult testes of 35-day old mice and subtracted it with mRNA from the testes of juvenile mice. Real-time RT-PCR analysis indicated that 42 cDNA clones in the subtracted library were expressed more intensely in the adult testes than in the juvenile testes. One clone identified by subtraction is expressed preferentially in the late spermatid and is located on chromosome 17E3 in mouse and 2p22 in human. (omitted)

• Journal of Korean Institute of Industrial Engineers
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• v.36 no.4
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• pp.212-218
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• 2010

This paper shows accuracy comparison results of reliability estimation methods for one-shot systems with respect to sample sizes. To compare accuracy in reliability estimation methods, quantal-response data, characterizing one-shot systems, were simulated using failure times of LED obtained through the accelerated life test, and then the true reliability over time was evaluated using the failure times. The simulated quantal-response data were used to estimate the true reliability through applying reliability estimation methods in open literature. Accuracy of each reliability estimation method was compared in terms of both SSE (Sum of Squared Error) and MSE (Mean Squared Error), and then estimation trend for each method is found. Feasible bounds which true reliability would exist within were estimated through applying the found trends to quantal-response data set of a real weapon system.