• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.10
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• pp.719-726
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• 2010

In this paper, the appropriate thermal storage time of an air-conditioning system with slab thermal storage was considered by use of summer measurement values. Two standards of heat extraction rate and criterion function were established as the standard that evaluates appropriateness. When heat extraction rate was a standard, zero hour and seven hours were obtained as appropriate thermal storage time, in the case of evaluation by energy consumption and running cost individually. Also, when criterion function was a standard, the difference between energy consumption and running cost was small, it was because the weight function to room air temperature deviation was much bigger than heat extraction rate.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.3
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• pp.115-122
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• 2011

The critical role played by manufacturing performance measurement systems in achieving competitive success is increasingly recognized. Developing an integrated performance measurement model is significant for strategic management. This study consist of several principal steps. Performance criteria from the literature and an questionnaire were utilized prior to building the performance model. The AHP(Analytic Hierarchy Process) is utilized to evaluate the weight of each criterion when generating the performance measurement model for Korea automobile parts manufacturing company. AHP analysis showed clear difference in the priority between 5 criteria and 24 sub-criteria in terms of manufacturing performance of Korean automobile parts manufacturing company. The result of priority evaluation in the 5 criteria of 2nd level was ranked quality, cost, delivery, employee, flexibility. And the critical sub-criteria in the 24 sub-criteria of 3rd level was ranked claim rate, process defect rate, outsourcing parts defect rate, ability to quality management innovation, claim cost, etc.

• Journal of the Korean Vacuum Society
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• v.1 no.3
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• pp.371-375
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• 1992

Low cost, PC controlled electrical property measurement systems were constructed to study thin film characteristics such as ; I-V, C-V, C-t, and low current. In addition, a GPIB card and C language program for data control and analysis were made for this study.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.2
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• pp.222-231
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• 2016

This paper proposes a new method achieving computationally efficient attitude reference system for low cost strapdown sensors and microprocessor platform. The main idea in this method is to define and compare velocity differential vectors, geometrically computed from INS and GPS data with different update rate, for generating attitude error measurements which is further used for filter construction. A quaternion based Kalman filter configuration is applied for the attitude estimation with the adapted measurement model of differential vector comparison. Linearized model for Extended Kalman Filter and low pass filtered characteristics of measurement greatly extend the affordability of the proposed algorithm to the field of simple low cost embedded systems. For performance verification, experiment are done employing a practical low cost MEMS IMU and GPS receiver specification. Performance comparison with a high grade navigation system demonstrated good estimation result.

• Journal of Aerospace System Engineering
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• v.9 no.2
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• pp.41-46
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• 2015

The various risk factors that affected schedule, costs and mission success, etc. in development of the satellite. This paper derives the considerable "Cost of Quality" factors in the satellite development phase through the survey of practical techniques in respect of measurement of quality cost in the commercial products manufacturing, and proposes mitigation strategy of quality cost using the approach that can be minimized it.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.34
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• pp.147-153
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• 1995

Many companies have thought that the quality cost is inclosed as the quality is improved. But, this is not so. The quality cost is not monotonously increased in proportion to the quality improvement. The existing approach to quality cost has many problems. This paper deals with conceptual difference between the traditinal and the existing view points of quality cost as the measurement index of quality, and developed the right approach of quality cost in terms of the combination of the traditinal and the existing approach. The right approach of quality cost that proposed in this paper was involved the following results; The approach of quality cost based on the continuous quality improvement for customer satisfaction, and considered flexibility, time, and information when the quality measured and evaluated.

• The Journal of the Acoustical Society of Korea
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• v.37 no.2
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• pp.99-109
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• 2018

The precision of the vibration-sensors, contact or non-contact types, is usually satisfactory for the practical measurement applications, but a sensor is confined to the measurement of a point or a direction. Although the precision and frequency span of the low-cost camera are inferior to these sensors, it has the merits in the cost and in the capability of simultaneous measurement of a large vibrating area. Furthermore, a camera can measure multi-degrees-of-freedom of a vibrating object simultaneously. In this study, the calibration method and the dynamic characteristics of the low-cost machine vision camera as a sensor are studied with a demonstrating example of the two-dimensional vibration of a cantilever beam. The planar image of the camera shot reveals two rectilinear and one rotational motion. The rectilinear vibration motion of a single point is first measured using a camera and the camera is experimentally calibrated by calculating error referencing the LDV (Laser Doppler Vibrometer) measurement. Then, by measuring the motion of multiple points at once, the rotational vibration motion and the whole vibration motion of the cantilever beam are measured. The whole vibration motion of the cantilever beam is analyzed both in time and frequency domain.

• Journal of Information Technology Services
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• v.10 no.4
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• pp.229-242
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• 2011

It is necessary to have measurement and analysis activity for managing software project. At least, every project measures time and cost in order to figure it out whether it will finish within its deadline. CMMI has Measurement and Analysis process in Maturity Level 2. In Measurement and Analysis process, Indicators for decision making in project management are defined and analysis procedure of the measurements to get the indicators are specified. Also, the way of collecting the data and storing them is also planned. Establishing efficient and effective measurement and analysis process in the organization by improving existing process is very important for project success. In this paper, we provide a method for analyzing the measurement and analysis process and improving it based on IDEAL model. It will support the organizations which are trying to adopt CMMI to establish measurement and analysis process.

• Journal of the Ergonomics Society of Korea
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• v.14 no.1
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• pp.69-81
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• 1995

Few studies on the biomechanical analysis of hand postures and tool handling tasks exist because of the lack of appropriate measurement techniques for hand force. A measurement system for the finger forces and joint angles for the analysis of manual tool handling tasks was developed in this study. The measurement system consists of a force sensing glove made from twelve Force Sensitive Resistors and an angle-measuring glove (Cyberglove$^{TM}$, Virtual technologies) with eighteem joint angle sensors. A biomechanical model of the hand using the data from the measurement system was also developed. Systems of computerized procedures were implemented inte- grating the hand posture measurement system, biomechanical analysis system, and the task analysis system for manual tool handling tasks. The measurement system was useful in providing the hand force data needed for an existing task analysis system used in CTD risk evaluation. It is expected that the hand posture measurement developed in this study will provide an efficient and cost-effective solution to task analysis of manual tool handling tasks.s.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.3
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• pp.219-223
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• 2008

The dissolved oxygen (DO) sensors were fabricated by screen printing method, and potable dissolved oxygen measurement system was fabricated for low cost products. The fabricated sensors had high current change and fast response according to dissolved oxygen concentrations in the applied voltage of 0.7 V. The DO measurement system was consisted of MCV, amplifier, filter, power supply and display. DO concentrations were programed to display as digital percentages by converting the analog value. It is expected that the fabricated DO measurement system can replace the expensive commercial DO meter, because it reveals the high accuracy of ${\pm}0.5%$ to the standard solution and the response time of about 100 sec like the commercial DO meter.