• 한국지반신소재학회논문집
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• 제22권3호
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• pp.27-35
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• 2023

굴착 공사 중 가시설의 안정성을 확보하는 것은 매우 중요하다. 설계 시 지반의 안정성을 수치해석을 통해 분석하고 있지만, 시공시에는 여건이 달라지기 때문에 계측으로 벽체 안정성을 분석하는 일은 필수불가결한 일이다. 공사현장에서의 계측비용은 매우 낮은 단가로 책정되어있으며 이를 통해 흙막이 벽체의 사고위험성은 예측되고 있다. 따라서 본 연구에서는 흙막이 벽체의 자동 혹은 무선 시스템 계측의 중요성을 가상의 사고사례 분석을 통해 공사기간 및 사고비용을 산정하고 이를 계측비용과 비교하여 무선 및 자동계측 업무의 중요성을 주장하였다. 굴착공사 중 중대형 파괴 시 사고처리 금액에 대하여 계측비용은 5% 미만으로 계측비용을 증가시켜 사고를 미연에 방지하는 것이 경제적일 수 있다.

• 한국기계가공학회지
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• 제12권3호
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• pp.61-68
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• 2013

Automatic measurement system is required since cycle time and cost of production are increased by various factors in manual systems. This paper presents a machine vision based prototype measurement system for the automotive axisymmetric shape parts which are generally measured by a manual system that is required the tolerance of the part is very small on each machined surface. This measurement system adopts a method in which optical lens is transferred along the profile of the part to minimize measurement cycle time. The main interest of this paper is a development of an optimum measurement algorithm to the outside diameter of the parts that can be applied to various combinations of hardware. The operating system used to implement the whole system is Window XP and corresponding environment.

• 한국정밀공학회지
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• 제27권3호
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• pp.27-32
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• 2010

The OMM(On-Machine-Measurement) system has many advantages compare to conventional measurement in the way the time and cost. But, the sensor suitable to OMM system is restrictive use. Touch trigger probe sensor has long time for measurement and non-contact sensor has directional demerit. Because the long mechanical parts such as gear and lead screw for pump, injector and machine tools has big and heavy, unclamp and transferring for measurement in machining process is very difficult. This paper presents a development of ultra miniature eddy current displacement sensor with 3 axes for On-Machine-Measurement system. The accuracy of the sensor is experimentally proved in the grinding machine. In experimental results, the accuracy has under ${\pm}5\;{\mu}m$.

• 산업경영시스템학회지
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• 제32권4호
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• pp.223-227
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• 2009

The study presents two measurement split-plot models with a restricted randomization to save cost and time. Split-plot models are used to handle HTCM (Hard To Control Measurement) factors such as high temperature and long-time catalyst control. The models developed are represented by the processes for estimating the measurement precisions, that is, gauge R&R. The study also introduces three-step procedures to indentify resolution, improve R&R reduction, and evaluate the precision effect.

• 한국항공운항학회지
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• 제23권1호
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• pp.103-112
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• 2015

In this study, a study was carried out to see what influence low-cost carrier's e-service quality has on low-cost carrier customers' perceived value and customer satisfaction and what impact the results have on customer loyalty based on the results of previous studies related to e-SERVQUAL, an e-SERVQUAL measurement model for general e-commerce. In addition, a survey of consumers who have experienced using low-cost carrier experience through web sites was conducted. For the analysis of the data collected, SPSS 18.0 was used to conduct frequency analysis, factor analysis, reliability analysis, correlation analysis, and regression analysis and thus to test a hypothesis. Research findings showed that perceived value and customer satisfaction are closely related to customer loyalty, and it was also observed that the reliability factor on the service provided on the web site acts as an important influencing factor for customer loyalty in the perceived value and security factors such as payment by credit cards and protection of personal information serve as important one in terms of customer satisfaction. This study has its limitation in that samples of users who have experienced low-cost carrier are concentrated on specific ages and professions. In the future, it is required to conduct further studies on whether difference is made on the importance of measurement factors related to e-service quality by gender, age group, occupation, and e-service quality.

• 제어로봇시스템학회논문지
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• 제13권7호
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• pp.637-648
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• 2007

This paper presents a sensor fusion method based on indirect Kalman filter(IKF) for error compensation of low-cost inertial sensors and its application to the determination of attitude and position of small flying robots. First, the analysis of the measurement error characteristics to zero input is performed, focusing on the bias due to the temperature variation, to derive a simple nonlinear bias model of low-cost inertial sensors. Moreover, from the experimental results that the coefficients of this bias model possess non-deterministic (stochastic) uncertainties, the bias of low-cost inertial sensors is characterized as consisting of both deterministic and stochastic bias terms. Then, IKF is derived to improve long term stability dominated by the stochastic bias error, fusing low-cost inertial sensor measurements compensated by the deterministic bias model with non-inertial sensor measurement. In addition, in case of using intermittent non-inertial sensor measurements due to the unreliable data link, the upper and lower bounds of the state estimation error covariance matrix of discrete-time IKF are analyzed by solving stochastic algebraic Riccati equation and it is shown that they are dependant on the throughput of the data link and sampling period. To evaluate the performance of proposed method, experimental results of IKF for the attitude determination of a small flying robot are presented in comparison with that of extended Kaman filter which compensates only deterministic bias error model.

• 한국건설관리학회논문집
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• 제14권5호
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• pp.144-152
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• 2013

최근 건설프로젝트가 대형화되면서 건설사들은 PMIS(Project Management Information System)를 이용하여 대부분의 관리업무를 수행한다. 특히, 건설공사 수행과정에서 가장 빈번한 정보입출력이 발생하는 진도관리 기능은 PMIS의 여러 기능 중 가장 효율적으로 운영되어야 한다. 그러나 PMIS 내에서 입력되는 정보가 대부분 중복입력 없이 운영되고 있음에도 불구하고, 진도관리를 위한 데이터는 비용과 일정 정보의 개별 입력을 통해 관리되고 있는 실정이다. 따라서 물가상승, 설계변경 등에 의해 비용과 일정이 변경되는 사항에 대한 정보가 연계되지 못하여 진도측정의 부정확성과 PMIS에서 관리해야할 데이터의 증가를 유발한다. 이와 같은 문제를 해결하기 위해서 진도측정방법의 개선과 이를 기반으로 한 PMIS 진도관리 모듈의 구현이 요구되고 있다. 이에 본 논문에서는 수량산출정보 기반의 비용-일정 통합 진도측정방법과 비용-일정 통합관리에 필요한 PMIS 공통관리항목을 기반으로 한 PMIS 진도관리 개선 모듈을 제시하고자 한다.

• 품질경영학회지
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• 제37권3호
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• pp.94-101
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• 2009

It is important to measure financial effect of six sigma projects accurately for successful implementation of six sigma in a company. However, researches on methods of six sigma financial effect measurement are relatively new. In this study, frequent error patterns of six sigma financial effect measurement are defined and accurate measurement methods are suggested. And a method of connecting six sigma financial effect to corporate income performance is also suggested which not only assures reliability of financial effect measurement but also helps to align with business strategy.

• 한국공작기계학회논문집
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• 제13권6호
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• pp.34-40
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• 2004

This paper presents studies on curvature radius measurement using the laser interferometer. It is a general practice to measure to $10^{-10}$m in length with the recent improvement and innovations in measurement technology and the processor used. The measurement methods can generally be categorized as these two: the contactual method and non-contactual method; and in this study, we will find ways to lower the cost for a CMM, or a coordinate measurement machine, and try to find an alternative. Furthermore, we will discuss some of the ways to improve the non-contactual measurement methods-optical interferometer method and the optical triangulation method. We will measure an object using a laser distance measuring device and Set the Point-contact result with the ball-bearing type and line-contact result with the bearing type, to decide on which probe type will be used.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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• pp.361-364
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• 2001

Speech quality measurement is sorted subjective and objective speech quality measurements based on the mathematics representation. Between two, subjective speech quality measurement is able to be evaluated more accurate speech quality then objective one but it has a demerit such as taking much more time and cost to performance it. However, using objective speech quality measurement being able to predict the result of evaluating the subjective speech quality compliments the demerit of subjective standards which is mentioned former. In this paper, we propose the objective speech quality measurement in order to evaluate naturalness assessment approximately like subjective speech quality measurement. We measured naturalness of speech with estimating speaking rate, variation of pitch and energy.