• Title/Summary/Keyword: Material Selection

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The Selection of Optimal Mixing Proportion and Cost Analysis in the SFC (초유동 콘크리트의 최적배합 선정방법 및 경제성 분석)

  • Park, Chil-Lim;Kim, Moo-Han;Kwon, Yeong-Ho;Lee, Sang-Soo;Won, Cheol
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10a
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    • pp.262-268
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    • 1998
  • This research is to examine the selected method of optimal mixing proportion and cost analysis in the super flowing concrete. As confined water $ratio($\beta_p$)$ and K is introduced, itis to establish optimal mixing design of super flowing concrete according to the steps of paste, mortar and concrete. From paste and mortar test, it was led to $$\beta_p$$ and $K_p$satisfying the optimum condions depending on the kinds of binders. Then $$\beta_p$$ and $K_p$ is reflected to the mix condition of super flowing concrete. The result of test, the mix condition of super flowing concrete satisfied the quality performance of concrete with adjustment of additional rate of the superplasticizer. Besides, in case of design strength $350kg/\textrm{cm}^2$ of concrete, material cost in super flowing concrete is able to be reduced 5~16% in replacement of fly ash 30% in ordinary portland cement and slag cement.

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Concept Car Development using Personal Digital Design Process based on Engineering Technology (공학 기술 기반 개인 디지털 디자인 프로세스를 적용한 컨셉카 개발)

  • Maeng, Joo-Won;Cho, Chong-Du
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.5
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    • pp.9-19
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    • 2010
  • Every car manufacturer desires to reduce the new car development time spent in improving the safety, NVH, lightweight, reliability and environment friendly features of the car. Other considerations such as planning, exterior and interior styling, packaging, color, and material selection increase the complexity of the car design process. This paper proposes a personal DDP (Digital Design Process) to utilize the engineering analysis and design/styling software for car design. DDP can be efficiently used by a team of car research center or a studio with small number of engineers, helping ordinary engineers becoming ambidextrous in design as well as engineering applications. The concept model starts from idea sketch, rendering, and 3D surface model with CAS (Computer Aided Styling) to the final safety estimation by using proposed DDP based on engineering technology (CAD, CAE). The concept model proposed a hydrogen fuel cell sports coupe which could be available within next 10 years. The proposed DDP can not only reduce the new car development time but also be adapted into designing of varied products such as aircraft, yacht, electrical equipment and sports gear.

Selection of Resistant Hybrids of Atractylis Against Phytophthora drechsleri

  • Kim, Dong-Kil;Shim, Chang-Ki;Kim, Hee-Kyu
    • The Plant Pathology Journal
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    • v.17 no.4
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    • pp.227-230
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    • 2001
  • Bioassay techniques using young leaves and roots were developed to screen resistance of Atractylis spp. against Phytophthora drechsleri. Among 638 plants collected from various regions of Korea from 1994 to 1996, 67 were pre-screened in fields naturally infested with P. drechsleri, which is the causal pathogen of rhizome rot of Atractylis. Among the pre-screened sources, 18 (ca. 26.8%) were highly resistant to the pathogen in leaf inoculation. In the root inoculation test, abundant sporangia were formed in susceptible plant roots, while only a few or no sporangia were produced on the roots which were found resistant in the leaf inoculation test. Among the selected resistant plants, A. japonica 96066 and 96104 were used to cross with another species, A. macrocephala 96362 that showed high yield with good quality of rhizome but susceptible to the pathogen. The F$_1$hybrids designated as HA03 turned out to be resistant to the pathogen, indicating that resistant gene(s) was inherited. Among intra-species hybrids of A. japonica, HA07 and HA09 were resistant to the pathogen in leaf inoculation and moderate in root inoculation. However, HA08 was susceptible in both inoculation tests. This result suggests that the parent material might be genetically heterogeneous. Further genetic study should be carried out to verify this phenomenon.

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Continuous Quality Improvement of Medical Equipments Based on Clinical Monitoring: A Case Study of Dental Implants (의료기기에 대한 임상모니터링 기반의 지속적 품질개선: 치과용 임플란트의 사례)

  • Kim, Myung-Duk;Eom, Tae-Gwan;Kim, Young-Jin
    • Journal of Korean Society for Quality Management
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    • v.36 no.2
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    • pp.59-66
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    • 2008
  • Dental implant has recently become one of the most viable treatment options for regaining the oral function and dental aesthetics compared with conventional fixed or removable dentures. Dental implants vary in material, dimensions, geometries, surface properties, and interface geometries. It has been reported that there has been a proliferation of manufacturers who produce implants using various materials and surface treatments, and the dentist needs to select from over 2,000 different dental implants and abutments in a specific treatment situation. Unfortunately, however, no metrics have been specifically identified for the purpose of quality assessment and selection of an appropriate dental implant. This study aims to provide practical guidelines for quality assessment of dental implant based on clinical data. Like other medical devices and materials, the superiority related to specific characteristics of the dental implant needs to be verified through extensive clinical studies. The procedures of clinical monitoring for dental implants have been proposed along with a case study to exemplify the usefulness of clinical monitoring for the purpose of continuous quality improvement in medical industry.

An Introduction to Asia Cooperation Programme in Conservation Science(ACPCS, 2005) and the operation result (아시아권 문화재 보존과학 협력과정(ACPCS, 2005)에 대한 소개 및 운영 결과)

  • Jeong, So-Young;Chung, Yong-Jae;Kim, Yong-Han
    • 보존과학연구
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    • s.26
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    • pp.203-211
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    • 2005
  • The National Research Institute of Cultural Heritage(NRICH) conducted the Asia Cooperation Programme in Conservation Science(ACPCS) to facilitate and promote the regional cooperation in the conservation of cultural heritage among Asian countries. This course was promoted to provide an opportunity to study and work together, also to share a knowledge and experience in conservation field. The target countries were from 17 Asian countries, and this year our selection committee selected 2 specialist in cultural heritage conservation field and selected persons had participated in the ACPCS course during three months. NRICH provided the round-trip airline tickets, overseas travel accident insurance and a living allowance to the course participants. And we requested programme announcement to Korean National Commission for UNESCO and Ministry of Foreign Affairs and Trade to progress favorably. This course period was three months from 29 August to 25 November, and the fields were conservation and restoration of tangible cultural heritage such as metal conservation, stone conservation, material analysis, DNA analysis, dating, biological control management of cultural heritage, environmental monitoring and so on.

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A Study on HOSEONGKONGSINLOK awarded to Kim Yang-bo, a eunuch (내시 금량보 호성공신록권)

  • Shim Woo-choon
    • Journal of the Korean Society for Library and Information Science
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    • v.20
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    • pp.17-33
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    • 1991
  • This articles aims to analyze HOSEONGKONGSINLOK awarded to Kim Yang-bo, a eunuch, having major roles to take refuge the king Seon-jo when the Japanese invader rushed into Seoul in the time of Hideyoshi's Invasion of Korea in 1592. At that time, all meritorious retainer was to be rewarded equally by a given rules of the stipends and the gifts. But for the eunuch, differently from others, the portrait was not made to be handed down as a model. Instead one more clothes was given. This suggests that there were some differenciation of the class and the job in the evaluation of the merits. From this we can see that there might be some problems in the selection of the meritorious retainer, resulting in unfair awarding, and needing to be reevaluation from the historian. Even though somewhat worn out, this material has very important value as a historical source in terms of following viewpoint: 1) it contains all the name of the meritorious retainers at that time. 2) it suggests the social situation and affairs at that time more precisely. 3) it reveals the facts even some facts in the authentic records can be corrected.

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Factors Influencing the Effectiveness of Materials Handling Equipments Supplied in Agriculture

  • Park, Sung-Ha
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.4
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    • pp.503-507
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    • 2011
  • Objective: This paper presents the factors influencing the effectiveness of materials handling equipments in agriculture. Background: Agriculture is one of the job categories where work-related musculoskeletal disorders(MSDs) are the most common. Statistics shows that majority of farm workers is exposed to repetitive and forceful body movements, lifting, lowering, pushing, pulling, or carrying heavy materials. In such a working environment, materials handling equipments are required and introduced to assist in the prevention of MSDs and other farm injuries. Method: Examples of materials handling equipments are rail carts, portable lifts, and bale handlers. Contributing factors influencing the effectiveness of materials handling equipments supplied in agriculture were identified based on the lessons learned from previous government-funded ergonomic projects. Results: Contributing factors identified include: (1) forward-looking attitude for the standardization of farming, its environments, and handling equipments, (2) participation of farm members in the process and evaluation of project, (3) leadership of project manager, (4) reinforcement of safety education and training, and (5) project selection and priority of handling equipment. Conclusion: Government-funded research planners, farmers, ergonomists, and farm machine experts are recommended to consider the factors identified when implementing materials handling equipments in agriculture. Application: Actual or potential application of this research includes recommendation for the effective implementation of material materials handling equipments in agricultural sectors.

Postcardiotomy Mechanical Circulatory Support in Congenital Heart Diseases (소아개심술 후 시행한 순환보조장치의 임상적 고찰)

  • 권오춘;이영탁
    • Journal of Chest Surgery
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    • v.33 no.5
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    • pp.385-390
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    • 2000
  • Background: To review the experience that used both ventricular assist device(VAD) and extracorporeal membrane oxygenation(ECMO) for children with congential heart disease requiring postcardiotomy mechanical circulatory support. Material and Method: Between March 1993 and May 1995, we applied mechanical assist device using centrifugal pump to the 16 patients who failed to be weaned from cardiopulmonary bypass(n=15) or had been in cardiogenic shock in intensive care unit(n=1). The diagnosis were all congenital heart diseases and the ages of patients ranged from 20 days to 10 years (mean age=2.5$\pm$3.5 years). Result: The methods of mechanical circulatory support were LVAD(n=13), BVAD (n=1), and ECMO(n=2). The mean assist times were 54.0$\pm$23.7 hours. Post-assist complications were in orders: bleeding, acute renal failure, ventricular failure, respiratory failure, infection, and neurologic complication. It was possible for 9 patients(56.3%) to be weaned from assist device and 5 patients(31.3%) were discharged from hospital. There was no statistical significant between hospital discharged group and undischarged group by age, body weight, cardiopulmonary bypass time, and assist time. Conclusion: The ventricular assist device is an effective modality in salvaging the patient who failed to be weaned from cardiopulmonary bypass, but multiple factors must be considered for improving the results of mechanical circulatory support ; such as patient selection, optimal time of starting the assist device, and prevention and management of the complications.

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Small Target Detecting and Tracking Using Mean Shifter Guided Kalman Filter

  • Ye, Soo-Young;Joo, Jae-Heum;Nam, Ki-Gon
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.4
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    • pp.187-192
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    • 2013
  • Because of the importance of small target detection in infrared images, many studies have been carried out in this area. Using a Kalman filter and mean shift algorithm, this study proposes an algorithm to track multiple small moving targets even in cases of target disappearance and appearance in serial infrared images in an environment with many noises. Difference images, which highlight the background images estimated with a background estimation filter from the original images, have a relatively very bright value, which becomes a candidate target area. Multiple target tracking consists of a Kalman filter section (target position prediction) and candidate target classification section (target selection). The system removes error detection from the detection results of candidate targets in still images and associates targets in serial images. The final target detection locations were revised with the mean shift algorithm to have comparatively low tracking location errors and allow for continuous tracking with standard model updating. In the experiment with actual marine infrared serial images, the proposed system was compared with the Kalman filter method and mean shift algorithm. As a result, the proposed system recorded the lowest tracking location errors and ensured stable tracking with no tracking location diffusion.

The Development of a Qualitative Psychological Assessment of Bibliotherapy and the Examination of it Efficacy (독서치료 효과 측정을 위한 질적 심리평가도구 개발에 관한 연구)

  • Lim, Seong-Gwan
    • Journal of Korean Library and Information Science Society
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    • v.45 no.3
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    • pp.141-168
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    • 2014
  • Public libraries and the Library & Information Sciences departments at Korean universities are increasingly interested in the application of a variety of bibliotherapy methods. Bibliotherapy serves as a therapy to understand a client and participants basic material sources and the effects of that particular treatment (necessary for program verification of psychological tools utilized). Its design is based both on literature selection and employed activities tools. Currently, bibliotherapy has been used mainly as a method to understand and diagnose a client and participants using simple and uniform questions. The development of appropriate and, possibly, additional assessment tools and report forms required for bibliotherapy evaluations in this study will be applied to actual case scenarios to determine the validity of this program and/or tools.