• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.863-874
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• 2009

The engineering characteristics and the reinforcement effect of the elephant foot method were discussed with parametric study. The elephant foot method is adopted to support the loads transferred from tunnel crown and improve bearing capacity of elephant foot in poor ground condition. The evaluation of reinforcement effect, which has the mechanical relationship between ground condition, footing size and reinforcement system, was carried out through the previous research and numerical analysis. In addition, the simple design chart was proposed to estimate the applicability of the elephant foot reinforcement method. It will be practical for the engineer to determine the optimum reinforcement method for safe tunnelling in soft ground condition.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.636-639
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• 1996

We have developed a part of hydraulic stroke sensing cylinder using magnetic sensor that can detect each position under severe construction fields. In this paper, for evaluating the developed cylinder under various environment condition, thermal control systems and two hydraulic systems to be coupled consist of. The former is composed of an heater case, temperature sensor, and interface circuits which include SCR(silicon controlled rectifier) for the control of the voltage's phase. The latter is composed of an hydraulic cylinder for position control with solenoid valve (ON/OFF motion) and a load cylinder with proportional reducing valve. To obtain the various performance evaluation, it is carried out under high temperature condition in thermal system controlled by using Ziegler-Nichols PID tuning method and artificial disturbances such as impulse or constant force. The results show that the developed cylinder has good performance under the various environment condition.

• 한국자동차공학회논문집
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• 제20권2호
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• pp.1-7
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• 2012

A Failure data from operating condition includes various failures. Reliability evaluation by operating condition is more correct than test condition. Additional, the evaluation result by operating condition is widely used for quality assurance, forecasting amount of manufacturing at EOL. To discover valuable things from the failure data, arrangement of the failure data and information technique to handle data is needed among many failure data. This paper introduces a reliability prediction program to solve this problem based on the failure. And new technologies for parameters estimation with method of Graphic-Wizard-Parameters-Estimation and Genetic Algorithm are introduced.

• 산업경영시스템학회지
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• 제27권4호
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• pp.157-164
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• 2004

Trouble prevention of facilities in operation process plays an important role for improving facilities productivity as production systemization is installed with development of facilities automatization. Condition monitoring predicts machine's internal changes by periodically recording vibration occurred in the machine. This article considers a method of establishing statistical criteria for facilities troubles by utilizing machine condition evaluation and operation limit standards of ISO 10816-3.

• International Journal of Automotive Technology
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• 제7권1호
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• pp.43-49
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• 2006

In this paper, an index for the evaluation of a vehicle intake booming noise and intake sound quality were developed through a correlation analysis and a multiple factor regression analysis of objective measurement and subjective evaluation data. At first, an intake orifice noise was measured at the wide-open throttle test condition. And then, an acoustic transfer function between intake orifice noise and interior noise at the steady state condition was estimated. Simultaneously, subjective evaluation was carried out with a 10-scale score by 8 intake noise and vibration expert evaluators. Next, the correlation analysis between the psychoacoustic parameters derived from the measured data and the subjective evaluation was performed. The most critical factor was determined and the corresponding index for intake booming noise and sound quality are obtained from the multiple factor regression method. And, the optimal design of intake system was studied using the booming noise and the sound quality evaluation index for expectation performance of intake system. Conclusively, the optimal designing parameters of intake system from noise level and sound quality whose point of view were extracted by adapting comparative weighting between the booming noise and sound quality evaluation index, which optimized the process. These work could be represented guideline to system engineers, designers and test engineers about optimization procedure of system performance by considering both of noise level and sound quality.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.367-374
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• 2005

This paper proposes a sound quality index to evaluate the vehicle interior noise. The index was developed using a correlation analysis of an objective measurement and a subjective evaluation data. First, the objective set of measurements was obtained at two specified driving conditions. One is from a wide-open test condition and the other is from a constant-speed test condition. At the same time, subjective evaluation was carried out using a score of ten scale where 17 test engineers participated in the experiment. The correlation analysis between the psycho-acoustic parameters derived from the objective measurement and the subjective evaluation was performed. The most critical factors at both test conditions were determined, and the corresponding equations for the sound quality were obtained from the multiple factor regression method. Finally, a comparative work between previous index and present index was performed to validate the effectiveness of the proposed index.

• Smart Structures and Systems
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• 제14권2호
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• pp.129-144
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• 2014

In this paper, a fuzzy inference system and an analytical hierarchy process-based online evaluation technique is developed to monitor the condition of the 32-km Donghai Bridge in Shanghai. The system has 478 sensors distributed along eight segments selected from the whole bridge. An online evaluation subsystem is realized, which uses raw data and extracted features or indices to give a set of hierarchically organized condition evaluations. The thresholds of each index were set to an initial value obtained from a structure damage and performance evolution analysis of the bridge. After one year of baseline monitoring, the initial threshold system was updated from the collected data. The results show that the techniques described are valid and reliable. The online method fulfills long-term infrastructure health monitoring requirements for the Donghai Bridge.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.142-160
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• 2003

Most consumers have noted hair damage following coloring treatments. Proper evaluation of hair bleaching products must be performed using quantitative assessments of hair damage, though they are difficult, because of the slight fluctuations in hair composition. In the present study, we utilized a sensitive evaluation method for hair damage and found that the amount of soluble protein fraction extracted from hair under a reducing condition, termed labile protein, dramatically increased after bleaching.(omitted)

• 한국환경복원기술학회지
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• 제8권6호
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• pp.45-58
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• 2005

The objective of this study is to the integrated evaluation of the present condition and satisfaction of visitors of rooftop greening area using quantitative and qualitative method. The thirteen green roofs were selected to investigate environmental variables as like building structure, soil, water, atmosphere and climate environment and questionnaire survey for investigate the satisfaction of visitors was conducted. The results of this study are as follows : remove of the hazardous inflow of species, install rain water recycling facility, install outdoor unit of air condition where not to affect plants in green roof, install safety facilities in the case of making resting place, plant variable vegetation and so on. The result of questionnaire survey are that visitors want to make more comfortable resting space. The more bigger the resting space and privacy, the more satisfaction of visitor became high. In conclusion, green roofs implementation should be considered reduction of temperature and delay of runoff, insulation effect and ecological restoration as well as rooftop greening is focused on the development of resting space nowadays.

• 한국정보통신학회논문지
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• 제17권12호
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• pp.3030-3037
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• 2013

위성통신설비의 수명은 설비별 사용빈도와 운영환경에 따라 상이하나, 설비 개대체시 내용년수만을 고려하고 있는 실정이다. 따라서, 설비의 성능분석을 통한 상태평가 및 의사결정에 따른 과학적 근거를 기초로 한 경제적인 자산관리가 필요하다. 본 연구에서는 K-water에서 사용하고 있는 위성통신설비에 대하여 물리적 평가, 성능분석 평가, 경제성 평가, 내용년수 평가를 통한 과학적인 상태평가표를 제안하였으며, 이를 통한 합리적인 개대체 방안을 수립하였다.