• The Mathematical Education
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• v.57 no.1
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• pp.55-74
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• 2018

The purpose of this study is first to examine the relative influence of each error source and to investigate the optimal measurement conditions to ensure satisfactory multiple reliability coefficients based on the teaching aptitude and personality test for pre-service teachers. Participants were 33 students enrolled in mathematics education in a graduate school of education located in the Seoul metropolitan area from 2013 to 2017. The main results were as follows. First, the estimated variance due to residual was highest, followed by nesting of items within domains, graduate students, interactions of graduate students with domains, and domains. Second, total 96 items, with 12 domains containing 8 items in each domain, with cut score of 598, and original 210 items, with 14 domains containing 15 items in each domain, with cut scores of 615 or 716 were optimal measurement conditions to reach acceptable reliability levels based on the joint consideration of dependability coefficients, cut score dependability coefficients, adjusted dependability coefficients, and standard errors of measurement. Third, larger deviations between the arithmetic mean and the cut score indicated higher reliability coefficients of the test results. Finally, this study suggests ways for practitioners to consider how to apply generalizability theory for criterion-referenced tests and how to develop future research based on limitations.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.3
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• pp.254-262
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• 2015

This paper presents 3D collision deformation modelling methodologies using photogrammetry for reconstruction of vehicle accidents. A vehicle's deformation shape in collision provides important information on how the vehicle collided. So effective measurement(scanning) and construction of a corresponding appropriate model are essential in the analysis of collision deformation shape for obtaining much information related to collision accident. Two measurement methods were used in this study: Indirect-photogrammetry which requires relatively small amount of photos or videos, and direct-photogrammetry which requires large amount of photos directly taken for the purpose of 3D modelling. When the indirect-photogrammetry method, which was mainly used in this study, lacked enough photographic information, already secured 2D numerical deformation data was used as a compensation. This made 3D collision deformation modelling for accident reconstruction analysis possible.

• Proceedings of the KIEE Conference
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• 2005.05b
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• pp.51-53
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• 2005

Grounding systems are responsible rot the safe operation of a power system whetehr power system fault occures or not, their performance guarantees equipmet protection and personnel safety by limited the ground potential rise and touch voltages as well as step voltages under ground fault condition. therefore, it is necessary to measure the ground resistance frequently for checing the performance of grounding system. In order to verigy the designed grounding measurement system feasibility, two comparison verifications, which are the ground resistnace measurements using the designed system on power service and off power service, are carried out for the same substation.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1438-1442
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• 2003

This paper presents the calibration service for the temperature sensor via the Internet. The purpose of the calibration service is to provide the teleoperate calibration procedure without skillful technician requirement at the client site. Besides the automatic measurement equipment that eases the operation, the developed software emphasizes the reliability of operation, simplifying the measurement data recording and processing, and achieving quality of the temperature measurements.

• Health Policy and Management
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• v.5 no.2
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• pp.202-229
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• 1995

In Korea, Resource-Based Relative Value Scale(RBRVS) is suggesting to the alternative of Korean Medical Fee Schedule. This study developed to methodology of RBRVS applicable to Korean situation and applied to services of internal medicine and general surgery. Our methodology of RBRVS is basically same to Hsiao's. But there are some differences between our method and H냐매's because Korean medical situation differs to American. The first difference is method of measurement of work. The Unit of work in our study is total work including intra-servic work and pre-/post-service work. Secondly, in extrapolation, we use primary data gathered to small group of physician. Tertially, in measurement of practice cost, we directly survey to budget data of hosptials and analyse practice costs by service. Some results are presented in a companion article.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.347-352
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• 1998

The purpose of this paper is to present and establish a procedure to predict the prestress forces during the service life of the structure. The statistical approach of this procedure is using the in-situ measurement data of the post-tensioning system to develop a nonlinear regression analysis. The method of least squares is used to fit a certain function a set of data. Use of a nonlinear model is achieved by its logarithmic transformation and sunsequent use of linear-regression theory. The regression analysis result can be used to check the prestress force during the service life so that the remaining prestress force is equal to or exceeds the design requirement. Results from the measurement data of PSC box girder bridge structure were used to demonstrate the procedures.

• Journal of the Korean Society for Heat Treatment
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• v.11 no.1
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• pp.54-61
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• 1998

Since Cr-Mo-V steel has excellent fracture and creep properties at elevated temperature, they are extensively used as steam turbine components such as the turbine rotor. However, the turbine rotor steel used to suffer material degradation during long term service. Therefore, the assessment of the safety and residual life of the turbine rotor is periodically required during service. One of the most convenient techniques for that is the hardness method mainly due to its simplicity and nondestructive characteristics. In this research, six specimens with different aging times of turbine rotor steel were artificially prepared by an isothermal heat treatment at $630^{\circ}C$. The micro Vickers hardnesses of specimens were measured at room temperature. The relationships between the fracture properties and the hardness ratio were investigated. And also an indirect method to evaluate the residual life of degraded turbine rotor was proposed based on the micro Vickers hardness measurement.

• Management & Information Systems Review
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• v.7
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• pp.247-263
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• 2001

To evaluate customer satisfaction of hotel food and beverage products, developing items for the measurement is necessary through studying the properties of food and beverage products. The properties consist of human service, physical and systematic service. Human service includes appearance and uniforms, courtesy and kindness, quickness and precision of the service, well-educatedness, moral sense and etc. Physical service includes the taste of food and beverage, diversity of food and beverage, outlets' cleanness and atmosphere, refinement of fixture, furnishing and table ware, the admission passage to the hotel and parking lot facilities, and etc. Systematic service includes passages of movement to outlet, arrangement of outlet, reservation management system, operation of events and package goods, temperature and ventilation system and etc. The price is also one of important variables to measure customer satisfaction index, so it is included to the investigating items. As shown some hotels have several satisfactory items but most items are unsatisfactory because expected service is better than perceived service. Therefore, the hotels which lack human service need the reinforcement of service education, the hotels which lack physical and systematic services need the improvement, the development and the renovation according to the unsatisfactory items. And the hotels whose price item is unsatisfactory need to consider the policy.

• Journal of Broadcast Engineering
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• v.12 no.1 s.34
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• pp.11-27
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• 2007

T-DMB(Terrestrial-Digital Multimedia Broadcasting) for portable and mobile broadcasting service was officially launched in the metropolitan area of Korea in December 2005. The development of interactive data services and the expansion of T-DMB network have been now progressed, and the regional T-DMB broadcasters will be selected in the near future. Although it is important to evaluate service area and reduce a fringe area for optimizing RF coverage of T-DMB, there was no professional system to support those works, and therefore lots of resources in budget, manpower and time were required. The measurement considering characteristics of SFN(Single Frequency Network) is essential in the implementation of T-DMB network which needs to control synchronization, spacing and output power of transmitters. In addition, mobile measurement, enough measured parameters for many-sided analysis of reception quality, efficient management of enormous measured data and representation of measured results on the electronic map are also important in evaluating service area. In this paper, we derived requirements for a new measurement system in T-DMB by considering the above details, and we proposed and developed an integrated measurement and analysis system. The developed system was applied to the implementation of T-DMB network of KBS and field tests, and it proved its efficiency and accuracy in result.

• Journal of KIISE:Information Networking
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• v.34 no.5
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• pp.396-404
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• 2007

In this paper, an Ad-hoc Routing Protocol which works in wireless Ad-hoc communication networks with multiple radios and multiple channels, and controls call admission based on bandwidth measurement is proposed. Unlike the conventional Ad-hoc node with a single radio using a single channel, an Ad-hoc node of the protocol proposed, MCQosR(Multiple Channel Quality of Service Routing), has multiple radios and uses multiple channels, which makes full duplex transmission between wireless Ad-hoc nodes, and reduces the intra interference on a route. Also, a fixed channel only for reception at each node enables the measurement of the available bandwidth, which is used to control the call admission for QoS provision. The performance of MCQosR is verified by simulation.