• Journal of Power System Engineering
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• v.9 no.4
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• pp.102-109
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• 2005

An attachment part of the construction equipment frequently claimed from the crack occurrence that takes especially at the bucket. therefore we execute the fatigue examination and changes the welding method at the same materials. we executed a fatigue crack propagation experiment and got the conclusions at the normal temperature and Frequency 10Hz. We carried out butt welding for structure steel of SM490A and make three kinds of specimen of different weld method each. The fatigue limit of CASE 1 was determined to the low than CASE 2, CASE 3. the CASE 2 putting the interval of the 2mm creates back plate and make fatigue limit to high. Bead shapes and weld surfaces shape influence on fatigue life of materials. Specially, the crack growth becomes starting point that gap of back-plate and boundary surface of bead. It is confirmed by fracture showing on this study.

• Journal of Oriental Neuropsychiatry
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• v.12 no.1
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• pp.193-200
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• 2001

This is a case report that dysautonomia and catatonia are accompanied by Akinetic Mutism in a 28 year old patient whose symptoms, seemed to catatonic schizophrenia. This study is aimed to assist about comprehension, diagnosis and treatment of dysautonomia and catatonia are accompanied by Akinetic Mutism, because this case is not common. This patient's chief complains that hyperhidrosis, muscular rigidity, akinesia etc are seemed to Neuroleptic Malignant Syndrome. Neuroleptic Malignant Syndrome is a side effect during taking antipsychotic that unknowned high, fever, stupor, muscular rigidity, akinesia, tachycardia, hyperhidrosis, salivation. We cannot rule out Neuroleptic Milignant Syndrome, but this case is seemed to catatonic schizophrenia. The symptoms of catatonic schizophrenia is that prodrome(relaxed concern, ataraxy, lacked concentration) is progressed and akinesia, mutism, ankylosis, stupor etc, are appeared. Oriental medicine, environment with more objective study and treatment are needed.

• Research in Mathematical Education
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• v.11 no.1
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• pp.65-74
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• 2007

The algorithmic idea has been a kind of necessary mathematics quality for modern people in this information society. In China the algorithm was represented fully as one of the new mathematics contents in the secondary level for the first time when The Standards of Mathematics Curriculum for the Senior High School was promulgated in 2003, so the research about the teaching algorithm undoubtedly has its practical implications for mathematics education. In this paper, with the conceptual framework of The Mathematics Task Framework as the research tool, an algorithmic teaching case based on LOGO software was introduced in detail, and data by ways of observations, interviews and worksheets were collected, then the case was analyzed. The results showed that the teaching of algorithm is feasible and effective in the LOGO environment. Some beneficial implications about the instructional design of algorithm were also discussed.

• Communications for Statistical Applications and Methods
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• v.20 no.6
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• pp.455-466
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• 2013

In nested case-control studies, the most common way to make inference under a proportional hazards model is the conditional logistic approach of Thomas (1977). Inclusion probability methods are more efficient than the conditional logistic approach of Thomas; however, the epidemiology research community has not accepted the methods as a replacement of the Thomas' method. This paper promotes the inverse probability weighting method originally proposed by Samuelsen (1997) in combination with an approximate jackknife standard error that can be easily computed using existing software. Simulation studies demonstrate that this approach yields valid type 1 errors and greater powers than the conditional logistic approach in nested case-control designs across various sample sizes and magnitudes of the hazard ratios. A generalization of the method is also made to incorporate additional matching and the stratified Cox model. The proposed method is illustrated with data from a cohort of children with Wilm's tumor to study the association between histological signatures and relapses.

• Transactions of Materials Processing
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• v.8 no.6
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• pp.604-611
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• 1999

This paper is concerned with the family of parts that generally feature a central hub with radial protrusions. As opposed to conventional forward and backward extrusion, in which the material flows in a direction parallel to that of the punch or die motion, the material flows perpendicular to the punch motion in radial extrusion. Three variants of radial extrusion of a collar or flange are investigated. Case I involves forcing a cylindrical billet against a flat die, Case II involves deformation against a stationary punch recessed in the lower die, and Case III involves both the upper and lower punches moving together toward the center of the billet. Extensive simulational work is performed with each case to see the process conditions in terms of forging load, balanced and symmetrical flow in the flange. Also, the effect of the gap size and die corner radii to the material flow are investigated. In this study, the forming characteristics of radial extrusion will be considered by comparing the forces, shapes etc. The design factors during radial extrusion are investigated by the rigid-plastic FEM simulation.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.53-56
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• 2007

Magnesium sheet used in electrical device due to mobility and EMF shielding characteristics. Magnesium case by press forming was advantageous compare with conventional die casting process, because of its thin gauge of wall and surface quality. But it need to makes the boss to fix inner part or assemble the case. CD stud welding was effective way for joining the boss to the thin gauge case of the electrical devices. In this study, we investigated the performances of the magnesium boss welder To measure the process parameters such as the force and the weld current, we design the monitoring system for CD stud welding. We test the characteristics of CD stud welding for AZ31 sheets at some variables. Finally we select the optimum welding range of magnesium sheets in CD stud welding process.

• Journal of Engineering Education Research
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• v.19 no.2
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• pp.8-13
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• 2016

This paper is concerned with the development case of CEA(Course-Embedded Assessment) design tool for engineering education accreditation operations department for CEA system implemented. Each university or programs are already devoting efforts to build research and CEA system for CEA applied to. In order to effectively apply the CEA studies for each program it is required and particularly, the preferred way to build an operating system is considered a difficult situation of the course unit. Therefore, this case study and to propose a method and procedures required to assessment the design basis for curriculum and program assessment unit in terms of the applicability of CEA, proposes a virtual application results. The information proposed in this case study is determined that could be used in the design for the outcomes and assessment of a variety of programs as one of the steps to build the CEA systems.

• Journal of Surface Science and Engineering
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• v.35 no.4
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• pp.206-210
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• 2002

The use of Spectra fibers as fiber cloth is increasing because of their excellent impact resistance. However, a major limitation on the use of Spectra fibers is a chemical inertness. In this Study, Spectra fibers were surface-treated using Ar$^{+}$ ion beam under oxygen environment to improve the tensile property of Spectra/vinylester composites. The effect of surface treatment of Spectra fibers on the tensile property of Spectra/vinylester composites was determined from tensile tests using Spectra/vinylester composite specimens with and without a hole. It was found that the tensile stiffness and strength of surface-treated case were 22% and 17% higher than those of untreated case for specimens with no hole. The maximum load of surface-treated case was about 15% higher than that of untreated case for specimens with a hole.

• Asia-Pacific Journal of Business
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• v.3 no.2
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• pp.1-7
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• 2012

The purpose of this case study is to discuss the issues and challenges pertaining to industrial safety. The case study begins with the shocking incident of the brutal killing of top-executive of the company by agitated workers. Inspite of having conducive environment for business, Italian subsidiary Robusto Muro Ltd had to confront industrial Relations issues at an incredible and unprecedented level. Management perspective, workers viewpoint, competitors approach and diplomatic comments by political bigwigs have also been incorporated so that the students may have 3-dimensional understanding of the scenario. The case of such genre will facilitate the students to comprehend and discuss the employee-employer relationship and industrial safety, in particular and industrial relations and IR machinery, in general.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.3
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• pp.71-81
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• 2007

Government-driven informatization support projects for small and medium companies turn into collaborative information technology alliances between mother companies and their suppliers. These collaboration efforts are driven by a mother company that can influence and support its suppliers. A mother company establishes a proprietary evaluation system for suppliers' informatization level and enforces the suppliers to use their ERP (Enterprise Resource Planning) systems above a certain level. This paper presents a Samsung Electronics case to find determinant factors for ERP system usage level. This case study aims at providing long-term strategies for the collaboration project and helping the suppliers effectively pursue their informatization projects. Furthermore, the case study will reveal issues and tasks for the mother companies to accomplish sustainable success for their suppliers' informatization.