• The Mathematical Education
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• v.44 no.1 s.108
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• pp.15-40
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• 2005

This study basically investigates the meaning and properties of performance task applicable to mathematics classroom and it finds out how to run effectively performance task activities included in the present mathematics textbooks. To accomplish this, this study deals with twelves kinds of mathematics textbooks for ninth graders and is proceeded on the basis of textbook analysis and teacher interview. Considering a situation that in future mathematics textbook would be developed, according to the analytic results of this study, common understanding of performance task and qualified performance task are needed, a variety of tasks classified by differentiated level are needed. In addition, each task should be dealt with the contents related to curious and interesting real-life situations. Furthermore, fairness of checking and recording should be established and teachers' positive attitudes to applying performance tasks to math class are needed.

• Journal of Educational Research in Mathematics
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• v.11 no.1
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• pp.207-221
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• 2001

The purpose of this study is to develop the assessment rubric of mathematical communication ability by each type: listening, speaking, reading, writing, and graphic. This rubric is qualified in the content-validity and reliability by professional educators' evaluation and correlation coefficient. 16 math educators judged that this involves the results of learning mathematical communication, the results of possible instruction, and the content of scoring mathematical communication by teachers. 170 middle school students were tested by the assessment task according to the types of mathematical communication. After two researchers and two teachers scored the tasks, correlation coefficient was calculated between evaluators. The coefficient is evaluated high in that it is more than 0.70.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.6-9
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• 2005

In this study, the ultra precision centerless grinder for ferrule grinding was designed. As the good-qualified ferrule is required a precise and fine grinding, grinding machine for ferrule must have a high accuracy and a sufficient stiffness. The centerless grinder is composed of the high damping concrete bed, grinding wheel spindle unit, regulating wheel spindle unit, feeding table and dressing unit. For a newly developed centerless grinder, hydrostatic system with high precision feeding and high stiffness was proposed. The grinding and regulating wheel spindle units were composed of hydrostatic spindle and feeding table was hydrostatic table. The prototype of hydrostatic table was manufactured and tested.

• Journal of the Korean Statistical Society
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• v.21 no.2
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• pp.111-125
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• 1992

Since Zadeh's definition for probability of fuzzy event is presented, alternative definitions for probability of fuzzy event is suggested. Also various properties of these new definitions have been presented. In this paper it is our purpose to show the works continued by finding a natural definition of a fuzzy probability measure on an arbitrary fuzzy measurable space. Thus, the main process is to observe fuzzy probability measure to be qualified by weak axioms of boundary condition, monotonicity and continuity suggested by Klir (1988). Especially, we will show that these axioms are satisfied through in succession of modifications from the Yager's method.

• Transactions of Materials Processing
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• v.20 no.2
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• pp.93-98
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• 2011

Electroforming is a kind of metal molding technology. After gilding on the possession object(conductivity, nonconductivity) separate it with possession object and produce a part or duplicate. This process has an excellent ability of duplicating detailed figure. To simplify the manufacturing process of a rotary screen, this study was adopted electroforming technology and produced silicon rubber mandrel. Furthermore, to indicate the optimal condition for the acquisition of high-qualified rotary screen product, the experiment was executed with pH, time, sulfamate nickel solution according to density which were the main factors to decide the condition, then compared it with the product made by original "S" company in Holland. As a result, the figure of hole was more obvious and correct. Also the open size increased by more than 2-3%.

• Asian Journal of Innovation and Policy
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• v.3 no.2
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• pp.154-171
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• 2014

This article aims to examine the achievement and limitation of adaptation of supply chain management (SCM) to IT human resource development (HRD) in Korea and to derive the implication of the Korean experience to other countries. In late 1990s, the IT New Deal Policy and the quantitative expansion of IT HR were introduced. Since mid-2000s, there has been much innovation in IT products as well as increased demand of highly qualified IT experts. The SCM in IT HRD was introduced in 2004 and continuously developed more. Since the late 2000s, IT convergence expanded to traditional industries and the new IT-based-industries were created in Korea. In this regard, Korea established the Seoul Accord as an international IT engineering education accreditation system in 2008. In response to the paradigm change, in 2011, the Korean government developed TOPCIT, which is a kind of competency test for evaluating IT competency.

• 보존과학연구
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• s.31
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• pp.141-154
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• 2010

Many bronze artifacts have been excavated and preserved through conservation treatments in Korea but the analysis on artifacts was regarded as destruction of artifacts from the academic world of archaeology, Therefore, it is not so available to perform research on production techniques and provenances by with qualified analysis. Accordingly, there were only a few study cases about quality properties and production techniques But recently gradual change started to appear from the awareness of the need for the scientific approach to excavated artifacts. While Korean ancestors already had applied the different alloying ratios according to the use and shape of bronze artifacts, the analysis and study have been restrictedly performed. As a result, there was only a few analysis cases on a small minority of artifacts because they are the ancient relics, which made it hard to understand the bronze artifacts more deeply. This study researched into components rate, production techniques and hardness of bronze weapons such as a bronze sword and compared their alloying ratios with those of Chinese old records (周禮考工記, 金之六齊).

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.467-472
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• 1996

This study discusses special aspects of severe accident related recriticality modeling and analysis in the Advanced Neutron Source (ANS) reactor.$^{1, 2)}$ The analytical comparison of three elements core to former two elements case is conducted including evaluation of suitable nuclear cross-section sets to account for the effects of system configulation, fuel and moderator mixture temperature, material dispersion and the other thermal-hydraulics. Three elements core ANS reactor is the alternative core design which was proposed as a modified core design, with three fuel elements instead of two, that would allow operation with only 50% enriched uranium (former uranium fuel is the baseline design value of 93%) A comprehensive test matrix of calculations to evaluate the threat of a criticality event in the ANS is described. Strong dependencies still on geometry, material constituents, and thermal-hydraulic conditions are verified. Therefore, the concepts of mitigative design features are qualified.d.

• Journal of the Korean Society of Visualization
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• v.4 no.1
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• pp.8-13
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• 2006

Fire simulation has been developed for decades to analyze fire cases and provide a tool to study fundamental fire dynamics and combustion. There are three way of fire simulation which are a full scale simulation, an experimental simulation and a computational simulation. In case of a full scale simulation, because a higher cost, a higher risk, more efforts are needed, a demand for it has been decreased. But recently a demand for an experimental simulation and a computational simulation has been increased. A computational simulation has several advantages; lower cost, short period, many case studies, more visual results, a quantitative result and etc. FDS(Fire Dynamics Simulator) which has been developed in BFRL(Building and Fire Research Laboratory), NIST(National Institute of Standards and Technology) is a popular world wide code for fire simulation. Lack of accurate predictions by the model could lead to erroneous conclusions with regard to fire safety. All results should be evaluated by the informed judgment of the qualified user.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.12
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• pp.42-49
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• 2007

When micro holes are machined by EDM, machining characteristics of machined holes are changed according to the machining conditions. Typical machining conditions are the kind of dielectric fluids, capacitance and ultrasonic vibrations. They influence electrode wear, machining time, radial clearance and taper angle. In this paper, machined holes whose depths are 300, 500, $1000\;{\mu}m$ are observed for each machining conditions. Using deionized water as a dielectric fluid makes electrode wear small, machining time short, radial clearance large and taper angle small. High capacitance makes electrode wear high. Ultrasonic vibrations make electrode wear large, machining time short, radial clearance small and taper angle small. From the results of experiments, the optimal machining conditions were obtained to machine highly qualified micro holes.