• JSTS:Journal of Semiconductor Technology and Science
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• 제13권5호
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• pp.522-529
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• 2013

In this paper, simple but very effective techniques to suppress subthreshold hump effect for high-voltage (HV) complementary metal-oxide-semiconductor (CMOS) technology are presented. Two methods are proposed to suppress subthreshold hump effect using a simple layout modification approach. First, the uniform gate oxide method is based on the concept of an H-shaped gate layout design. Second, the gate work function control method is accomplished by local ion implantation. For our experiments, $0.18{\mu}m$ 20 V class HV CMOS technology is applied for HV MOSFETs fabrication. From the measurements, both proposed methods are very effective for elimination of the inverse narrow width effect (INWE) as well as the subthreshold hump.

• 한국정밀공학회지
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• 제22권7호
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• pp.47-53
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• 2005

Microholes with high aspect ratio are required in microstructures. Among various methods for producing the microhole, micro electrical discharge machining (MEDM) is very effective and useful process. But, it is difficult to machine the high aspect ratio holes below $100\;{\mu}m$ in diameter because machining condition becomes unstable due to bad removal of debris at deep hole. In this paper, ultrasonic vibration is applied to MEDM work fluid to make a high aspect ratio micro hole. It is shown that the vibration is effective in circulating the debris and increasing the machining rate. As a result, produced was a micro hole with $92\;{\mu}m$ entrance diameter, $81\;{\mu}m$ exit diameter and aspect ratio 23.

• 대한안전경영과학회지
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• 제10권1호
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• pp.67-73
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• 2008

National Education Information System (NEIS) is an ambitious reform project that can improve the competitiveness and performance of education field and to link administrational work of between schools and their senior administration offices via internet. NEIS is introduced to lighten the teachers' overburden, to standardize the work process and to bring better quality education to each classroom and make it possible for those involved in education to resolve any related educational problem on line. This paper aims to construct a hierarchy model consisting of key factors such as technological and administrative factors for the effective use of NEIS and to evaluate the relative importance among key factors using fuzzy AHP technique included fuzzy concepts. Eventually, the analysis results can be utilized to develop the future improvement strategy of NEIS and to satisfy the users.

• 대한치과기공학회지
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• 제8권1호
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• pp.31-36
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• 1986

This treatise suggests the effective method for the dental laboratory technology teaching plan. It will present concrete practical steps for and audio-visual dental laboratory technology education approach. It will also help students to understand the dental laboratory theory and practice learned in the class and make use of it greatly in the field work. As follows: 1. Instructor should teach interestingly basic dental laboratory technology theory with illustrations and figures on the teaching method. 2. In practical traing class, instructor should teach every step, using audio-visual materials such as slides and video tapes/Instructor and his assist and should show an example to the students. 3. Instructor should make a standard and train the studtnes repeatedly until they come up to it. 4. Students should be skilled in every case through field work during their spare time and vacation. 5. Instructor should also teach job moral and manner to the students so that they can be adapted themselves to the social activities and be successful dental laboratory technician after graduation.

• 대한안전경영과학회지
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• 제19권4호
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• pp.253-260
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• 2017

Due to dramatic changes in the trend of corporate management in economics, labor and government, companies are being asked to adapt creative and innovative organizational culture in order to keep sustainability. Under the circumstances, flexible working hour becomes one of very effective method for organization culture improvement. Recently, M company has introduced the new policy of working hours that employees can choose a couple of different time options depending on their personal situations. And it turns out to be very effective to work & life balance, increasing organizational vitality, improving efficiency of business and productivity, recruitment of core human resources, and prevention of deviation; both team and personal performance levels has significantly improved. Therefore, it is highly recommended to adapt flexible working policies for companies seeking for a long term, sustainable corporate vision.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.583-587
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• 2015

Scenario-based learning (SBL) has been used in a variety of training situations across different disciplines. Despite its seemly widespread use in construction management discipline, very few attempts have been made to explore its effectiveness and the respective students' learning experience. Using a survey research design, this study aims to investigate students' perceptions on SBL approach in construction management courses. The specific objectives are: (i) to identify the characteristics of a favourable SBL environment, and (ii) to explore the students' learning experience and effectiveness of the SBL approach. The results show that the four characteristics of a favourable SBL environment are: effective team formulation, constant engagement with lecturer, working in a group, and incorporation of motivational incentive for participation. The students really appreciated the opportunities to apply concepts learnt in the lectures in their SBL group work. Also, they perceived that the SBL approach is effective in developing their reflective and critical thinking skills, analytic and problem-solving skills and their ability to work as a team. These findings should facilitate more critical approaches to similar form of teaching methods.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.229-230
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• 2023

The introduction of digital technology for supervision work can be explained as an important key to improving construction productivity. In this study, effective digital technologies at construction supervision work is analyzed in terms of productivity improvement. And through questionnaires, effective technology introduction strategies is devised.

• 대한인간공학회지
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• 제30권4호
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• pp.443-450
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• 2011

Objective: The aim of this paper is to introduce ergonomic guidelines and intervention procedures for farm workers. Background: It is necessary to ameliorate the conditions of risky and hazardous work for farm workers. Method: Various references and books have been reviewed to assess ergonomic guidelines and intervention procedures for farm workers. Results: Human centered intervention has become an important approach not only to prevent musculoskeletal disorders but also to enhance the efficiency of work for farm workers. Conclusion: Farm work should be improved by active cooperation with researchers in field of ergonomics. Application: These results can be used to provide baseline information for more effective improvements of farm work.

• 한국정밀공학회지
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• 제24권7호
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• pp.39-48
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• 2007

This paper presents a method of a line balanced assembly sequence generation based on the verification of a disassemblability and a work time. To derive the disassemblability for a part to be disassembled, first we inference collision free assembly directions by extracting separable directions fur the part. And we determine the disassemblability defined by the separability and stability cost. The separability cost represents a facility of the part disassembly operation, and the stability cost which represents a degree of the stability for the base assembly motion. Based upon the results, we propose a new approach of evaluating work time using neural networks. The proposed assembly sequence generation provides an effective means of solving the line balancing problem and gives a design guidance of planning assembly lay-out in flexible manufacturing application. Example study is given to illustrate the concepts and procedure of the proposed schemes.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1995년도 추계학술대회 논문집
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• pp.60-63
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• 1995

The behavior of the work materials in the chip-tool interface in extremely high strain rates and temperatures is more that of viscous liquids than that of normal solid metals. In these circumstances the principles of fluid mechanics can be invoked to describe the metal flow in the neighborhood of the cutting edge. In the present paper an Eulerian finite element model is presented that simulates metal flow in the vicinity of the cutting edge when machining a low carbon steel with carbide cutting tool. The work material is assumed to obey visco-plastic (Bingham solid) constitutive law and Von Mises criterion. Heat generation is included in the model, assuming adiabatic conditions within each element. the mechanical and thermal properties of the work material are accepted to vary with the temperature. The model is based on the virtual work-stream function formulation, emphasis is given on analyzing the formation of the stagnant metal zone ahead of the cutting edge. The model predicts flow field characteristics such as material velocity effective stress and strain-rate distributions as well as built-up layer configuration