• Journal of Korean Institute of Industrial Engineers
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• v.39 no.5
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• pp.325-341
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• 2013

During the past several decades, the Taguchi robust design method has been widely used in various fields successfully. On the other hand, some researchers and practitioners have criticized the method with respect to the way of utilizing orthogonal arrays, the signal-to-noise ratio as a performance measure, data analysis methods, etc., and proposed alternative approaches to robust design. This paper introduces the Taguchi method first, evaluates the validity of the criticisms, and discusses advantages and disadvantages of each alternative. Finally, research issues to be addressed for effective robust design are presented.

• International Journal of Internet, Broadcasting and Communication
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• v.9 no.1
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• pp.42-49
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• 2017

Despite the government's various safety measures, the number of safety accidents continues to rise and the interior is more likely to occur indoors than outdoors. Safety accidents involving young children account for more than 70 % of the safety accidents in the safety accidents, and the ratio of safety accidents in the classroom or classroom is more than 50 %. In this thesis the author proposes the system managing the accidents notification service using LED lighting and access entry control. Utilizing IoT technology, remote control or access can be controlled remotely by controlling multiple lights and entrances from each room and by means of a number of lighting and entrances. By monitoring and analyzing real-time status via server PC and mobile interface, it can control the maximum control and incident prevention, automatic control, and automatic control.

• Journal of the Korea Society for Simulation
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• v.9 no.1
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• pp.21-38
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• 2000

A fuzzy dispatching algorithm with adaptable control scheme is proposed for more flexible and adaptable operation of AGV system. The basic idea of the algorithm is prioritization of all move requests based on the fuzzy urgency. The fuzzy urgency is measured by the fuzzy multi-criteria decision-making method, utilizing the relevant information such as incoming and outgoing buffer status, elapsed time of move request, and AGV traveling distance. At every dispatching decision point, the algorithm prioritizes all move requests based on the fuzzy urgency. The performance of the proposed algorithm is compared with several dispatching algorithms in terms of system throughput in a hypothetical job shop environment. Simulation experiments are carried out varying the level of criticality ratio of AGVs , the numbers of AGVs, and the buffer capacities. The rule presented in this study appears to be more effective for dispatching AGVs than the other rules.

• Asian Journal of Innovation and Policy
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• v.12 no.1
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• pp.101-130
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• 2023

The increasing cost, and demand for, household energy has increased attention to the phenomena of energy burdens. Despite this increased attention, a lack of consensus remains in pinpointing the strongest predictors, and geographic differences, that exist within the energy ecosystem. This study addresses this gap by utilizing a series of dummy variable regressions across cities, suburbs, and rural areas within Erie County, New York-a county noted to have particularly high energy burdens. Specifically, three types of predictor sets were incorporated into the methodology: a set of socioeconomic variables, physical variables, and a combination of both variable sets. The results of this study suggest that cities tend to have the highest electricity burdens. Despite the aging infrastructure in Erie County, high energy burdens were driven primarily by socioeconomic factors such as housing cost burden and poverty status. Lastly, this study explores various planning and policy implications Erie County can utilize to reduce energy burdens. In turn, this study highlights the importance of focusing policy efforts on existing social service programs to provide support to the region's neediest households.

• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.522-526
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• 1994

There are great needs for checking machine operation status precisely in the iron and steel plants. Rotating machines such as pumps, compressors, and motors are the most important objects in the plant maintenance. In this paper back-propagation neural network is utilized in diagnosing rotating machines. Like the finger print or the voice print of human, the abnormal vibrations due to axis misalignment, shaft bending, rotor unbalance, bolt loosening, and faults in gear and bearing have their own spectra. Like the pattern recognition technique, characteristic. feature vectors are obtained from the power spectra of vibration signals. Then we apply the characteristic feature vectors to a back propagation neural net for the weight training and pattern recognition.

• Publications of The Korean Astronomical Society
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• v.13 no.1 s.14
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• pp.209-223
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• 1998

We have investigated future large telescopes, which should represent the next generation of Korean optical and infrared telescopes. We first studied the history of the development of large telescopes in the USA, European countries, and Japan. Based on these studies, we came up suitable Korean large telescopes, which fit the current status of Korea in terms of financial situation, required technology, sciences, and manpower. We presented the potential impacts of developing large telescopes on the relevant Korean industry and Korean astronomical society. We also discussed a possibility to install large Korean telescopes at foreign sites utilizing highly competitive seeings and twice available observing dates there.

• Progress in Superconductivity
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• v.8 no.1
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• pp.16-21
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• 2006

In this paper, current status of experimental and theoretical work on quantum bits based on the semiconductor quantum dots in the University of Seoul will be presented. A new proposal utilizing the multi-valley quantum state transitions in a Si quantum dot as a possible candidate for a quantum bit with a long decoherence time will be also given. Qubits are the multi-valley symmetric and anti-symmetric orbitals. Evolution of these orbitals is controlled by an external electric field, which turns on and off the inter-valley interactions. Initialization is achieved by turning on the inter-valley Hamiltonian to let the system settle down to the symmetric orbital state. Estimates of the decoherence time is made for the longitudinal acoustic phonon process.

• Journal of Korea Society of Digital Industry and Information Management
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• v.15 no.2
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• pp.11-17
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• 2019

As interest in the efficiency use of energy has been recently rising, studies have been performed in utilizing various types of eco-friendly green energy and natural energy. Especially there has been rapidly increase in the fields using ESS (Energy Storage System), which is the technology for storing the energy from nature. The application fields of ESS is continuously growing and expanding to various types of technologies. However, in recent years there have been continuing problems with the safety of ESS. And related researches are going on. In this paper, we has proposed a system structure to utilize more secure ESS and has monitored the system status of ESS in real time by using smart phone app. This paper has also proposed a new method to configure secure ESS by implementing GUI (Graphical User Interface) to control the system. And then explain experimental results to investigate the efficiency of the proposed ESS.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2000.11b
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• pp.131-136
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• 2000

The purpose of this study is to identify the perceptual differences among independent elderly relative. to falls risk associated with specified environmental design factors. The sample consisted of 135 independent elderly who live in Ulsan. The data were collected by utilizing questionnaire which included demographic information, and environmental design assessments accompanied by line drawings. The data were analyzed by using SAS program. The major findings were as follows: (1) There were 35(25.9％) elderly experienced fall(s) within one year and about half of the fallers fell more than once. (2) The elderly perceived lighting is the most hazardous interior design factor related to increased risk of falls. (3) There was a significant difference among age groups on perception of lighting as interior design factors and the elderly perceived differently floor as interior design factors by their perceived health status.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.1
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• pp.15-21
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• 2014

Modern aircraft air navigation has been changed from the conventional air navigation aid to utilizing Global Navigation Satellite System. For the air navigation of fast moving aircraft, GNSS required extremely high accuracy and reliability. This study reviews the basic concept of Satellite Based Augmentation System which is discussed in the International Working Group of International Civil Aviation Organization and status of some SBAS leading State's case. In addition to that, a progress of SBAS development and implementation in the Republic of Korea was reviewed with pointing out of general hurdles and counter measures.