• Geomechanics and Engineering
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• v.12 no.4
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• pp.723-738
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• 2017

Rock is a heterogeneous material, which introduces complexity in the analysis of rock slopes, since both the existing discontinuities within the rock mass and the intact rock contribute to the degradation of strength. Rock failure is often catastrophic due to the brittle nature of the material, involving the sliding along structural planes and the fracturing of rock bridge. This paper proposes an advanced discretization method of rock mass based on block theory. An in-house software, GeoSMA-3D, has been developed to generate the discrete fracture network (DFN) model, considering both measured and artificial joints. Measured joints are obtained from the photogrammetry analysis on the excavation face. Statistical tools then facilitate to derive artificial joints within the rock mass. Key blocks are searched to provide guidance on potential reinforcement measures. The discretized blocky system is subsequently implemented into a discontinuous deformation analysis (DDA) code. Strength reduction technique is employed to analyze the stability of the slope, where the factor of safety can be obtained once excessive deformation of slope profile is observed. The combined analysis approach also provides the failure mode, which can be used to guide the choice of strengthening strategy if needed. Finally, an illustrated example is presented for the analysis of a rock slope of 20 m height inclined at $60^{\circ}$ using combined GeoSMA-3D and DDA calculation.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.6
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• pp.309-314
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• 2003

A spark plasma sintering technique has been used for the fabrication of $Al_2O_3$-SiC nanocomposites at the low temperature of $1100^{\circ}C$∼$1500^{\circ}C$. The sintered $Al_2O_3$-SiC composites shows very homogeneous microstructure without any particular abnormal grain growth, indicating that the addition of nano-sized SiC particles is very effective to control grain growth and to induce the residual stress in the $Al_2O_3$ matrix, resulting in the intragranular fracture. These SiC particles are present in the grain boundaries and also intragrain, depending on the sintering condition, and improve remarkably the mechanical properties of $Al_2O_3$-SiC composite through the mechanisms of strengthening and toughening induced by crack diffraction and crack bridging.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.8 no.1
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• pp.49-61
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• 2013

Objectives: The aim of this study was to analyse the domestic trends of Chuna treatments techniques in Korean literature. Methods: We searched the clinical trials on Chuna treatments through both electronic search(used keyword 'chuna') and hand search in 3 Korean web databases(OASIS, NDSL, RISS) and 4 related journals(The Journal of Korea CHUNA Manual Medicine for Spine & Nerves, Journal of Oriental Rehabilitation Medicine, The Journal of Korean Acupuncture & Moxibustion Society, Journal of Korean Medicine Society). All relevant clinical trials were selected and extracted to be analyzed according to their published year, journals, types of study, used techniques. Results: The number of the clinical studies tends to increase every year. The studies on Chuna treatments were mainly published in The Journal of Korea Chuna Manual Medicine for Spine & Nerves. In case of types of study, case reports and case series were predominant. The most frequently adopted techniques of Chuna in studies were flexion distraction technique for lumbar spine and JS supine position cervical spine distraction. Conclusions: Through the results of this study, we hope that the more qualitative education could be conducted by strengthening the techniques which often used. Also analysis of the reason of rarely used techniques should be conducted and the modification or developing techinques should be followed as a counter measures. As applying more rigorous methodology, more qualitative evidence based Chuna studies should be conducted in future clinical research.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.1
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• pp.55-60
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• 2002

For the development of a new creep test technique, the availability of SP-Creep test is discussed for 1Cr-0.5Mo boiler header material. And some results are also compared with those of 2.25Cr- 1Mo steel which widely uses as boiler superheater tube. The results can be summarized as follows. The load exponents(n) obtained by SP-Creep test for 1Cr-0.5Mo steel are decreased with increasing creep temperature and the values are 15.67, 13.89, and 17.13 at 550$^{circ}C$ ,575$^{circ}C$ and 600$^{circ}C$, respectively. The temperature dependence of the load exponent is given by n = 107.19 - 0.1108T. This reason that load exponents show the extensive range of 10∼16 is attributed to the fine carbide such as M$_{23}$C$_{6}$ in lath tempered martensitic structures. At the same creep condition, the secondary creep rate of 1Cr-0.5Mo steel is lower than the 2.25Cr-1Mo steel1 due to the strengthening microstructure composed by normalizing and tempering treatments. Through a SEM observation, it can be summarized that the primary, secondary, and tertiary creep regions of SP-Creep specimen are corresponding to plastic bending, plastic membrane stretching, and plastic instability regions among the deformation behavior of four steps in SP test, respectively.y.

• Journal of Korean society of Dental Hygiene
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• v.6 no.3
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• pp.203-218
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• 2006

The purpose of this study was to measure dental hygienists' perception of the usefulness of clinical practice training. A total of 195 dental hygienists participated in the study. The findings of the study were analyzed according to age, the type of hospitals where respondents were working, experience in clinical practices and educational level as follows: 1. There were statistically significant differences in perception of the usefulness of the practice of amalgam filling preparation performed for dental operation among subjects at different ages (p<.01). 2. There were statistically significant differences in perception of the usefulness of the practice of paralleling technique(p<.001), the practice of amalgam filling preparation(p<.01) and the practice of trauma treatment preparation(p<.05) among subjects working at different clinics 3. Significant differences were observed in perception of the usefulness of the practice of sterilization(p<.05), the practice of suction(p<.05), the practice of history taking preparation (p<.01) and the practice of halitosis patient management preparation(p<.05) among subjects with different years of experience in clinical practices. 4. Significant differences were found in perception of the usefulness of the practice of paralleling technique among subjects with different education levels. The findings of the study suggest the need for strengthening education programs for clinical training content and practices which subjects considered important for their job. At the same time, the study emphasizes the need for developing training programs designed to produce dental hygiene preceptor who can provide dental hygienists with practical clinical training in cooperation with college and dental clinics.

• East Asian Journal of Business Economics (EAJBE)
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• v.8 no.1
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• pp.21-40
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• 2020

Purpose - The labor management department is an important area in charge of the labor-management relations that affects the competitiveness of the company. This study seeks to diagnose labor management education focusing on labor manager competency strengthening curriculum that is currently being conducted domestically and propose an educational model that can contribute to the labor manager competency development by researching improvement measures. Research design, data, and methodology - In this study, the first phase is a Delphi open form survey and 15 expert panels participated. The second phase had 31 expert panels participating and in the final IPA analysis, targeting 111 on-site subjects, it conducted a survey regarding desired level of current educational level and future education requirement. Results - A final 57 subjects regarding 11 items to increase the competency of the labor managers through the first and second Delphi survey was deduced through this study. To add, regarding the current education level and desired level that the current workers are thinking with respect to analysis results of the 57 subjects through the IPA analysis, an educational model could be deduced to increase competency of the labor managers based on the result. Conclusions - Thus far, research regarding labor management has been insufficient as it was defined as a subordinate role to human resources. This study reviews the role and competency of labor managers and presented an educational model to strengthen the capabilities of internal labor managers to re-illuminate the labor manager. However, this study is limited in terms of the diversity of the types of companies participating and the small number of panels. Better data can be produced if such parts are supplemented in the future.

• The Korean Journal of Archival Studies
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• no.61
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• pp.119-156
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• 2019

The records centers service of public institutions helps efficient work activities of internal users, who actually do the work, and becomes the foundation for strengthening the competitiveness of the institution. Based on QFD technique, one of the quality control techniques, this study was intended to propose a plan to improve the quality of the records center service by analyzing and comparing the quality of the records center service of public institutions. To this end, as a follow-up study of Lee, Su-jin(2018), the research target was expanded to local governments to apply the QFD technique and reconstructed the HoQ based on the results of the expanded QFD application. Moreover, this study suggested measures to improve the quality of service in the records center of public institutions by compiling the implications of comparing the records center service HoQ and prioritizing the technology characteristics of the records center service.

• Korean Journal of Computational Design and Engineering
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• v.15 no.2
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• pp.94-105
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• 2010

Todays, there is fast transition about the new manufacturing IT methodologies from the conceptual phase into the practical application phase for the strengthening of enterprise competitiveness in manufacturing industry. One of those new methodologies is PLM (Product Life-cycle Management). PLM methodology consists of 3D CAD for the product design, PDM (Product Data Management) for the data management based on the collaboration platform and lastly DM (Digital Manufacturing). DM has evoluted from the stand-alone computer simulation of early 1980s, and now it covers the overall production development and production. Unfortunately, there exist serious critical problems about the actual application of DM for the real work. This is owing to the transition of the point of view from stand-alone type application (such as flow simulation or robot simulation) to that of business process about product development and production management. In this paper, we propose an application framework for the successful project with the digital manufacturing methodology with the concept of Information Strategy Planning, which enables the systematic diagnosis and the quantitative evaluation. Also, we introduce the actual practice of the proposing framework with the ISP project for 'Analysis & Simulation Technique of manufacturing process project' that is being conducted by Chungnam Techno Park.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.467-472
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• 2010

Individual vacuum pressure method is soft ground improvement technique, in which a vacuum pressure can be directly applied to the vertical drain board to promote consolidation and strengthening the soft ground. This method does not require a surcharge load, different to embankment or pre-loading method. In this study, given the inner displacement of the ground where the individual vacuum pressure is applied, this dissertation aimed to reproduce the state of stress in the ground that is subject to the constraints created by the depth of improvement area. Modified Cam Clay theory which made it possible to take into account the isotropic displacement of the ground was applied to the NAP-IVP used simulation; the conception of equivalent permeability proposed by Hird was also applied so that the 3-dimensional real construction effect of drain materials could be reflected in the analysis.

• Journal of Korean Institute of Industrial Engineers
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• v.1 no.1
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• pp.41-56
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• 1975

In the past the pattern of business down-trend usually appeared in the form of, first, decrease in facility investment, then decrease in inventory level, followed by reduced level of consumption. But the pattern nowadays is becoming just the opposite, that is, first, consumption decrease, then inventory level increase, followed by restriction of facility investment. Also in the past, the greater effort was placed in strengthening of hardware areas through optimization and modernization of production means on the premise of sales. But lately software areas take most of the main effort to establish production mean with sales as its objective. Under these circumstances one of the real problems facing production activities today is the conflicting relationship between sales and production functions. This occurs due to differences of their view points. Then, in order to achieve maximum profit at the least cost, which is the ultimate objective of a production activity, the need arises to effectively coordinate sales demand and plant production capacity. For this purpose strong control means and function must be devised. In our case study example we illustrate a management technique for a combined planning function, of optimal coordination of product mixes utilizing a computerized linear programming model as control means of attaining maximum profit. It is hoped that this example help achieve some of corporate objectives.