• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.895-900
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• 2008

It is the objective of the present study to conduct correlation analysis for deriving control parameters in vertical shafts using the results obtain by the design of experiments in the preceding research. The control parameters are categorized into objective parameters, derived parameters, condition parameters, operation parameters, and sensing parameters. The maximum pressure in the shaft should be sufficiently small in order to maintain exhaust hood performance. The pressure variations between floors should also be minimized in order to maintain uniform exhaust performance between floors and to save energy for excessive pressure drop in the shaft. The standard deviation based on -4Pa is proposed as an objective parameter to control pressure in shafts. The correlation equation has been obtained between the standard deviation and the sensing parameters of outdoor temperature and the pressure at the top of the shaft.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.2
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• pp.81-90
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• 2013

A study on the flow-structure characteristics of marine 3/2WAY pneumatic valve is essential for optimizing the performance of ship engines. It is important that the valve has desirable safety factor and reduced weight from safety and economic point of view. In this paper, flow-structure characteristics of pneumatic valve is obtained by being optimized based on the proper design criteria. The air with the pressure of 30 bar is the working fluid which is made to fill in the tack in short time. This time is defined as the filling time. On optimum design by considering the flow-structure characteristics, the approach is based on (1) the mathematical formulation of design decisions using the compromise decision-making method, and (2) the approximation technique of response surfaces. The methodology is demonstrated as the multi-objective optimization tool to improve the performance of marine 3/2WAY pneumatic valve.

• Korean Journal of Optics and Photonics
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• v.3 no.3
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• pp.143-147
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• 1992

1)iscussed in this paper are the effects of phase modulation on the line spread functions (LSF) and MTFs of ;I binocular objective system. The binocular objective lens is made in Korea. It has rotationally symmetric aberrations. The LSFs and MTFs are measured experimentally. The phase modulation is carried out by applying phase retardation $\pi$ on the aperture. The area where the phase is not retarded presents a double annular type. The OTF curves of phase modulated aperture are compared with that of unmodulated aperture. The comparison shows that there is the aberration compensation effect in aberration loaded system. Therefore the performance of many optical system can be improved without any loss of light energy by properly modulating the phase on the aperture.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.2
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• pp.177-190
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• 2016

On-line consumer reviews are good references for consumers to evaluate and buy apparel products. The objective of this study is to facilitate communication about performance textiles between consumers and merchandisers who buy and sell apparel products on online. The survey was based on standardizing words used in consumer reviews written after purchase of summer knit t-shirts at internet shopping mall and evaluating the performance textiles including cellulose fibers. We collected reviews of five sorts of the clothing products including cotton/modal, tencel/polyurethane, polyester/rayon, linen, cotton and selected 1000 reviews related to textiles. For classifying each word used in the reviews by the performance textiles, they were quantified applying same standards. The results were as follow: First, the standard for consumer to consider importantly was tactile sensation, appearance, pilling, thickness, dimensional stability in washing. Second, the important category of performance textiles was healthy-comfort and psychological-comfort. Third, there were difference performance textiles for consumer to recognize, e.g. cotton/modal was important to air-permeability, tencel/polyurethane was noticed about tactile sensation, polyester/rayon was perceived about pilling unlike other things, linen had a problem of clothing care-convenience, then cotton was familiar fiber to important for appearance. The last, consumers usually focused on writing the most positive or negative online reviews. Although not familiar with professional terminologies, consumers are sensitive to physical properties of textiles. Therefore, standardizing and evaluating performance textiles are expected to improve satisfaction as providing objective information to consumers considering in buying apparel products at online shopping mall and increase in revenue to manufacturer.

• Journal of the Society of Disaster Information
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• v.10 no.2
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• pp.208-218
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• 2014

The growth of disaster/accident damage costs and related industries has increased the necessity of scientific and objective performance analysis for fire suppression and disaster management R&D projects. Most of R&D performance are both academic and public performance according to fire suppression and disaster management R&D projects during the period of 2004 to 2011. This research identified characteristics of performance types by research project teams and research development stages. The research outcome shows the usefulness of relevant performance objective settings by project teams, the evaluation of scientific technology fields, and proper research teams in research team selection process, considering research outcome characteristics by both research teams and research development stages. In addition, this research reveals the applicability of research outcomes to research performance management. This research suggests further studies for evaluation process and methods for including fire suppression and disaster management characteristics to the evaluation process.

• Safety and Health at Work
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• v.12 no.4
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• pp.462-470
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• 2021

Background: Fatigue is pervasive, under-reported, and potentially deadly where flight operations are concerned. The aviation industry appears to lack a standardized, practical, and easily replicable protocol for fatigue risk assessment which can be consistently applied across operators. Aim: Our paper sought to present a framework, supported by real-world data with subjective and objective parameters, to monitor aircrew fatigue and performance, and to determine the safe crew configuration for commercial airline operations. Methods: Our protocol identified risk factors for fatigue-induced performance degradation as triggers for fatigue risk and performance assessment. Using both subjective and objective measurements of sleep, fatigue, and performance in the form of instruments such as the Karolinska Sleepiness Scale, Samn-Perelli Crew Status Check, Psychomotor Vigilance Task, sleep logs, and a wearable actigraph for sleep log correlation and sleep duration and quality charting, a workflow flagging fatigue-prone flight operations for risk mitigation was developed and trialed. Results: In an operational study aimed at occupational assessment of fatigue and performance in airline pilots on a three-men crew versus a four-men crew for a long-haul flight, we affirmed the technical feasibility of our proposed framework and approach, the validity of the battery of assessment instruments, and the meaningful interpretation of fatigue and work performance indicators to enable the formulation of safe work recommendations. Conclusion: A standardized occupational assessment protocol like ours is useful to achieve consistency and objectivity in the occupational assessment of fatigue and work performance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.727-732
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• 2009

The objective of this study is to analyze and evaluate design factors relating to sound reduction performance in dry wall system. The main contents of this study are as follows. 1) Analysis and pre-evaluation of sound reduction performance of drywall system ; The sound reduction performance was pre-evaluated by INSUL simulation and these results of analyzing walls were analyzed by screening DOE(design of experiment) for selecting major factors that dominant influence the sound reduction performance. These main factors relating to sound reduction performance can be used for development of 1st grade sound reduction performance drywall system. 2) Design and evaluation of 1st grade sound reduction performance drywall system; The evaluation test of the sound reduction performance gave vaues higher than 1st grade (Rw+C=64). When campared with existing dry wall system, respectivelly, the new system shows performance higher than 8 dB.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.361-363
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• 2007

Using intelligent systems, many users do effectively their works. In general, the effective usages of the systems have to possess the usability and accuracy. So, we need some measurements for evaluating the performance of the criteria. But, in most cases, objective measurements for the evaluation are not. In this paper, we propose a measurement technique for objective evaluated measuring of intelligent systems using probability measure.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.372-375
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• 1989

In this paper, a new FTCS with the ability to perform original control objective without considerable loss of control performance in the face of any fault is proposed. The FTCS is composed of two interacting units, Adaptive Controller Unit and Fault Detection/Classification, where ACU performs primary control objective with basic process information(I/O) and environmental information fed by FDU and where FDU detect and classify faults and make decision on remidial action by the use of information provided by ACU.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.110.4-110
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• 2002

In practical control area, there are many examples with multiple objectives which may conflict or compete with each other like overhead crane control, automatic train operation, and refuse incinerator plant control, etc. These kinds of control problems are called multiobjective control problems, where it is difficult to provide the desired performance with control strategies based on single-objective optimization. Because the conventional control theories usually treat the control problem as the single objective optimization problem , the methods are not adequate to treat the multiobjective control problems. Particularly, in case of large scale systems or ill-defined systems, the multiple obj..