• Journal of Power Electronics
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• v.17 no.3
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• pp.695-703
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• 2017

In order to satisfy the urgent requirements for the overheating protection of induction motors, an approach that can be used to identify motor temperature has been proposed based on the rotor slots harmonic (RSH) in this paper. One method to accomplish this is to improve the calculation efficiency of the RSH by predicting the stator winding distribution harmonic order by analyzing the harmonics spectrum. Another approach is to increase the identification accuracy of the RSH by suppressing the influence of voltage flashes or current surges during temperature estimation based on model predictive control (MPC). First, an analytical expression of the stator inductance is extracted from a steady-state positive sequence motor equivalent circuit model developed from the rotor flux field orientation. Then a procedure that applies MPC for reducing the identification error of the rotor temperature caused by voltage sag or swell of the power system is given. Due to this work, the efficiency and accuracy of the RSH have been significantly improved and validated our experiments. This work can serves as a reference for the on-line temperature monitoring and overheating protection of an induction motor.

• Advances in materials Research
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• v.12 no.4
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• pp.287-308
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• 2023

The main objective of this article is to highlight the progress made in the development of new materials that have been gradually used by humans until today. Of course, this progress must be associated with other parameters in order to guarantee sustainable development. For this, today, it has become urgent to reduce the consumption of cement by resorting to its partial or total replacement by other similar materials in order to reduce CO₂ emissions in our environment. This should certainly help to develop greener building materials. In this study, it was decided to proceed with the partial or total replacement of Portland cement type CEM II/B-L-42.5N by slate and lime that had not undergone any previous transformation. The results obtained revealed that the mortar whose substitution compared to the replacement of cement (100%) cement and sand (0/4) confers better kinetics than those of the series composed of(100%) cement and fraction rubble (0/1).

• International Journal of Advanced Culture Technology
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• v.12 no.1
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• pp.281-286
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• 2024

With the commercialization and full-timeization of the livestock industry, civil complaints continue to increase, and the livestock industry is facing a crisis due to social problems such as odor caused by livestock manure, soil pollution, water pollution, and environmental pollution. In order to increase productivity in livestock farms, the amount of livestock manure generated is increasing due to excessive use of protein feed and high-density breeding environment, and complaints such as odor and water pollution due to management problems are increasing rapidly. Livestock odor has emerged as a serious social problem, and due to growing complaints, conflicts between the Ministry of Agriculture and Forestry and the Ministry of Environment are even causing the livestock industry to lower its status. There is an urgent need for solutions to identify problems in the livestock industry and improve policies. This study aims to develop a " Abelmoschus Manihot Jinhuakui " brand that can improve the intestinal environment of livestock, reduce odors caused by livestock excrement, and improve the productivity of livestock farms in order to improve the increasingly serious odor problem in livestock sites. For Jeju livestock farms, which place more importance on the environment by securing tourists, eco-friendly feed additives were applied to the experiment, the results were derived, and the focus was on solving fundamental problems of odor generation through the development and packaging of feed additive brands. We aim to fundamentally solve the odor problem of domestic livestock farms, secure eco-friendly livestock farms, and contribute to reducing livestock odors and increasing productivity through research results that reduce ammonia levels in each livestock farm.

• Journal of Korea Port Economic Association
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• v.20 no.2
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• pp.169-185
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• 2004

It is an urgent problem that Korea logistics enteprises' expansion of advance into China market and the logistics network establishment between Korea and China to back up the former are to be solved. Accordingly, the purpose of this study is to deduce the subjects to establish the logistics network between Korea and China, and to evaluate the priority order. The results of this research are as follows: First, we conducted face-to-face interviews on the advisery group in China and Korean enterprises which advanced into China, and drew out 6 promoting subjects to build the logistics network between the two. Second, the AHP model was adopted, which is a multi-criteria?multi-hierarchical decision making method, to draw out the weight and priority order of the deduced 6 promoting items. Third, the resultant priority order of the promoting subjects is as follows: No.1 - to establish the distribution & logistics support center by region(0.3900); No.2 - to support various taxes in investing the logistics business abroad(0.1980) ; No.3 - to improve the management of CIQ(0.1958); No.4 - to back up the joint-venture of logistics firms(0.1169); No.5 - to enhance trade and foreign policies to deregulate the entry into logistics markets(0.0536); No.6 - to construct the logistics information system of China(Northest Ssia)(0.0458). This paper resulted in finding out Korea logistics enterprises that have not secured their own inland-transport network in China and the actual difficulties of Korean enterprises with using the inferior network that advanced into China. These problems were developed into the analysis adopting the AHP method, and the significancy of this paper is to present the priority order of promoting problems using a sophisticated technique.

• Journal of Korea Port Economic Association
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• v.26 no.3
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• pp.221-239
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• 2010

This study aims to provide solutions concerned with to residential moving companies about their operational problems. In order to shed light on these problem, factor analysis and fuzzy AHP method are adopted. Selected factors are low quality of workers and equipments, weak condition of business, policy and form of a contract, and excessive competition. The results of survey show that excessive competition is the most urgent problem compared with other problems. In the twelve-measured variables, The problem of non-certificated firms, low service quality caused by excessive competition, and claims caused by lack of service instruction are chosen as the urgent matters. As a result of the analyses, the study would propose policy directions how to solve these problems. Firstly, the government should make the legal basis of operating the industry because there is too competitive in the field. Secondly, the government should regulate firms which have not a certificate because they are the cause of low service quality in the field. Thirdly, in order to improve the service quality, the study would suggest that the managers should instruct the workers of residential moving companies. Lastly, the paper would suggest that customers check the certificate of the firm allowed by the government authorities.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.6
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• pp.311-321
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• 2019

In this paper, we try to define and classify the concepts of Convergent Research of Korean-Western Medicine (CRKWM) to clarify the goals of research. In addition, some suggestions that are necessary to promote the CRKWM were made. The results are as follows. First, the CRKWM should be used as a concept that refers to 'interdisciplinary research' jointly conducted by experts in both Korean and Western medicines beyond their own fields. Second, True CRKWM is an "eclectic combination of East-West" that combines the advantages of traditional Korean medicine and western medicine to create a new field; it is necessary to redefine the concept of 'Integrative medicine', which is used in different context by the traditional Korean medicine and western fields in Korea, as an "eclectic combination of East-West" type. Third, In order to promote the CRKWM, it is necessary to convert the current dual medical system of relativism to one of pluralism. Forth, In order for CRKWM to be promoted, methodologies, theories, and models that become the backbones of convergence should be developed. As of now, systems medicine and network science are the best fit. Fifthly, In order to promote convergent clinical research, the development of Korean-Western diagnostic model that integrates the pathologies of Western medicine and symptoms of Korean medicine is urgent. Lastly, Mutual understanding between Korean and Western medicine fields should be preceded in order for CRKWM to be stimulated.

• Convergence Security Journal
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• v.20 no.4
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• pp.35-45
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• 2020

Cyber attacks on the aviation weapon system, a state-of-the-art asset, have become a reality and are approaching as a constant threat. However, due to the characteristics of embedded software of the current aviation weapon system, it is managed and operated without connection to the network in peacetime, so the response management to cyber attacks is relatively weak. Therefore, when a cyber attack becomes a reality, it is urgent to prepare and evaluate measures for the adverse effects that such attack will have on the execution of the Air Tasking Order(ATO). In this paper, we propose a framework for operational impact assessment in order to avoid confusion in ATO execution and systematic response to cyber attacks on aviation weapons systems. The proposed framework is designed to minimize the negative impact on operations against cyber attacks that may occur under no warning by analyzing the impact on air operations for each aviation weapon system and standardizing countermeasures for this. In addition, it supports the operational commander to make a quick decision to command for the execution of the operation even in a situation where a cyber attack occurs.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.219-221
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• 2022

Seoul Metropolitan City, the world's top 10 cities and Metro City, has traditional urban manufacturing industries such as printing, sewing, and mechanical metals. These manufacturing industries have developed in the form of mutual assistance by forming small business clusters according to detailed industries and processes. Due to the nature of the cluster, logistics between companies for each process in the cluster are being carried out quickly, but it is difficult for relatively small small business owners to prepare order processing services for consumers of finished products. Therefore, it is urgent to introduce an integrated order fulfillment service platform for collective business owners for smooth order and delivery processing. In this paper, we collect and analyze the existing Fulfillment Service data of small business owners in the printing industry among traditional urban industries, and design an artificial intelligence Fulfillment Service Platform system applying CRNN, k-NN, and ID3 Decision Tree algorithm. Through this study, it is expected to greatly contribute to the increase in sales and capacity of small business owners by enabling the use of individual orders and customized delivery services that can be used by any small business owner in the cluster.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.4
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• pp.31-49
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• 1989

It is of the most urgent necessity to get hydrological time series of long duration for the establishment of rational design and operation criterion for the Agricultural hydraulic structures. This study was conducted to select best fitted frequency distribution for the monthly runoff and to simulate long series of generated flows by multi-season first order Markov model with comparison of statistical parameters which are derivated from observed and sy- nthetic flows in the five watersheds along Geum river basin. The results summarized through this study are as follows. 1. Both two parameter gamma and two parameter lognormal distribution were judged to be as good fitted distributions for monthly discharge by Kolmogorov-Smirnov method for goodness of fit test in all watersheds. 2. Statistical parameters were obtained from synthetic flows simulated by two parameter gamma distribution were closer to the results from observed flows than those of two para- meter lognormal distribution in all watersheds. 3. In general, fluctuation for the coefficient of variation based on two parameter gamma distribution was shown as more good agreement with the observed flow than that of two parameter lognormal distribution. Especially, coefficient of variation based on two parameter lognormal distribution was quite closer to that of observed flow during June and August in all years. 4. Monthly synthetic flows based on two parameter gamma distribution are considered to give more reasonably good results than those of two parameter lognormal distribution in the multi-season first order Markov model in all watersheds. 5. Synthetic monthly flows with 100 years for eack watershed were sjmulated by multi- season first order Markov model based on two parameter gamma distribution which is ack- nowledged to fit the actual distribution of monthly discharges of watersheds. Simulated sy- nthetic monthly flows may be considered to be contributed to the long series of discharges as an input data for the development of water resources. 6. It is to be desired that generation technique of synthetic flow in this study would be compared with other simulation techniques for the objective time series.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.4_2
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• pp.587-594
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• 2022

In the 2000s, a lot of cable-type grand bridges are being built in consideration of economic aspects such as the reduction of logistics costs and the distribution of traffic volume due to rapid economic development. In addition, because the recently installed grand bridges are designed in an aesthetic form that matches the surrounding environment as well as the original function of the road bridge, and serves as a milestone in an area and is used as an excellent tourism resource, attracting many vehicles and people, there is an urgent need for a safety structure that can ensure the safety of not only vehicles but also people. In order to make cable-stayed bridge safe on wind for additional five safety structures, main girder models with and without safety structures for wind-tunnel experiments was made, and wind tunnel experiments was carried out to measure aerodynamic force coefficients. Also, wind-resistant analyses of 3D cable-stayed bridge were performed on the basis of wind-tunnel experiment results. From the wind tunnel experiments for the aerodynamic force coefficients of main girder with five safety structures and the wind resistant analyses of cable-stayed bridge without safety structure and with safety structure, it was concluded that the best form of wind-resistant safety was shown in the order of mesh, standard, bracing, hollow, and closed type. And wind-resistant safety of cable-stayed bridge with hollow and closed type on design wind speed 68.0m/sec was not secured. Finally, as five safety structures are installed, maximum rate of stress increments was shown in the order of steel main beam, steel floor beam, concrete floor beam and cables.