• International Journal of Precision Engineering and Manufacturing
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• 제4권4호
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• pp.57-63
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• 2003

Machining information such as form accuracy and surface roughness is an important factor for manufacturing precise parts. To this regard, OMM (On the Machine Measurement) has been researched for last several decades to alternate CMM (Coordinate Measurement Machine) process. In this research, the OMM system with a laser displacement sensor was developed for measuring form accuracy and surface roughness of the machined workpiece on the machine tool. The surface roughness was estimated comparing the sensory signal with the reference data measured from master specimen. Also, form accuracy was determined from the moving averaged raw data. In addition, the geometric error map constructed beforehand using the geometric errors of the machine tool was used to compensate the obtained form accuracy. The overall performance was compared with CMM result, and verified the feasibility of the measurement system.

• 산업경영시스템학회지
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• 제33권4호
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• pp.100-113
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• 2010

Manufacturing companies' cost competitiveness with respect to equipment management can be achieved by satisfying additional market demands by their own capacity without purchasing additional equipments. In essence, it can be accomplished by making continuous investigation into bottlenecks and improvement on them. Therefore, equipment performance measure systems should be designed so that they can support manufacturing companies' such endeavors. With the purpose of establishing an effective equipment performance measurement system for detecting and improving bottlenecks, this study (1) suggests some desirable features that such a system should have, (2) evaluates conventional equipment performance measurement systems in terms of their usefulness for the detection and improvement of bottlenecks, and (3) proposes an improved system. We also perform a simulation experiment to demonstrate the limitations of the conventional systems and show how the proposed system can resolve the problems.

• Architectural research
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• 제12권1호
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• pp.57-64
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• 2010

In recent years, interests and studies on the urban regeneration projects have been increased and largely conducted. It is a part of the effort that solves some social and economical problems occurred by deteriorated buildings and degraded infrastructures through new urban regeneration projects or redevelopment projects. However, the urban regeneration projects show the characteristics that can not guarantee in the project performance because the projects have various and complex stakeholders related to these projects and are exposed to lots of risks due to its huge scale. This study proposed the risk performance index method to improve the efficiency of the overall performance measurement for a mega-project by extending from the traditional cost/schedule based performance measurement system. The risk performance index method proposed in this study has a similar system to the EVMS, and makes possible to perform a three dimensional integrated performance measurement in cost/schedule/risk through 18 different indexes that compose the risk performance index.

• 열처리공학회지
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• 제12권4호
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• pp.294-302
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• 1999

Evaluation of Brinell standard hardness tester was carried out to secure its application as a national standard for Brinell hardness. Accuracies and reliabilities in load application, indenter diameter and indentation measurement were tested through evaluation of these components. The accuracies of load application for various loading conditions were within the limit of ISO and KS specifications. Errors in the indentation measurement due to the difference in personnel characters were successfully removed by utilising automatic indentation measurement system. In overall, the tester and the indentation measuring system were found to be eligible as a national standard of Brinell hardness.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.681-686
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• 2000

Machining information such as machined form and surface roughness accuracy is an important factor for manufacturing precise parts. To this regard, OMM(On the Machine Measurement) has been issued for last several decades to alternate with CMM. In this research, measuring system consisting of a laser probe is developed for machined form and surface roughness measurement on the machine tool. The obtained machined form accuracy is compared with reference one defined in CAD model. The measured surface roughness data is compared with measured master surface beforehand. Furthermore, using the pre-defined volumetric error map approach compensates the geometric accuracy of the machine tool. The overall performance is compared with CMM, and verified the feasibility of the measurement system.

• 한국정밀공학회지
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• 제17권7호
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• pp.232-240
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• 2000

Machining information such as machined form and surface roughness accuracy is an important factor for manufacturing precise parts. To this regard, OMM(On the Machine Measurement) has been issued for last several decades to alternate with CMM. In this research, measuring system consisting of a laser probe is developed for machined form and surface roughness measurement on the machine tool. The obtained machined form accuracy is compared with reference one defined in CAD model. The measured surface roughness data is compared with measured master surface beforehand. Furthermore, using the pre-defined volumetric error map approach compensates the geometric accuracy of the machine tool. The overall performance is compared with CMM, and verified the feasibility of the measurement system.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1591-1598
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• 2009

Recently, the researches on the urban regeneration projects have been performed very actively. It is a part of the effort that solves some social and economical problems occurred by deteriorated buildings and degraded infrastructures through new urban regeneration projects or redevelopment projects. However, the urban regeneration projects show the characteristics that can not guarantee in the project performance because the projects have various and complex stakeholders related to these projects and are exposed to lots of risks due to its huge scale. This study proposed the risk performance index method to improve the efficiency of the overall performance measurement for a mega-project by extending from the traditional cost/schedule based performance measurement system. The risk performance index method proposed in this study has a similar system to the EVMS, and makes possible to perform a three dimensional integrated performance measurement in cost/schedule/risk through 18 different indexes that compose the risk performance index.

• Smart Structures and Systems
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• 제8권1호
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• pp.53-67
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• 2011

Human state in human-machine systems highly affects the overall system performance, and should be detected and monitored. Physiological cues are essential indicators of human state and useful for the purpose of monitoring. The study presented in this paper was focused on developing a bio-inspired sensing system, i.e., Nano-Skin, to non-intrusively measure physiological cues on human-machine contact surfaces to detect human state. The paper is presented in three parts. The first part is to analyze the relationship between human state and physiological cues, and to introduce the conceptual design of Nano-Skin. Generally, heart rate, skin conductance, skin temperature, operating force, blood alcohol concentration, sweat rate, and electromyography are closely related with human state. They can be measured through human-machine contact surfaces using Nano-Skin. The second part is to discuss the technologies for skin temperature measurement. The third part is to introduce the design and manufacture of the Nano-Skin for skin temperature measurement. Experiments were performed to verify the performance of the Nano-Skin in temperature measurement. Overall, the study concludes that Nano-Skin is a promising product for measuring physiological cues on human-machine contact surfaces to detect human state.

• 동력기계공학회지
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• 제11권1호
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• pp.28-32
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• 2007

This research proposed that development of wireless condition monitoring system using WLAN network. It offers the prospect of improved performance that removed a current a coaxial cable and reduced overall cost of condition monitoring. Recently, there is an interesting concern for wireless system as an infrastructure technology construct ubiquitous computing environment in the future. High performance computing board makes minimization with integrate of a various functions which support wireless LAN network. Instead of wired coaxial cable using measurement system in industry, wireless LAN network assists industry automation and engineer's convenience. Developed system adapted wireless LAN network on shipboard with engine room and deck house, it also executes wireless measurement test on 8500TEU containership.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.151-154
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• 2000

We have developed a YBCO SQUID gradiometer system for the measurement of a very weak magnetic field in an unshielded environment. The system consists of a SQUID gradiometer sensor, low noise pre-amp, and FLL(fluxlocked loop) control electronics. The gradiometer sensors have been fabricated on STO bicrystal substrates, and exhibit a magnetic noise of 300 fT/${\surd}$ Hz/cm at 100 Hz. The overall magnetic field noise of the SQUID gradiometer system was about 10 pT/${\surd}$ Hz/cm at 10 Hz without any magnetic shield. The system demonstrated a high stability for a long time, and real-time measurement resolution ${\le}$ 100 pT/cm in the unshielded environments.