• Coupled systems mechanics
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• 제6권3호
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• pp.335-349
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• 2017

To cope with the demand on giant and durable buildings, reinforcement of concrete is a practical problem being extensively investigated in the civil engineering field. Among various reinforcing techniques, fiber-reinforced concrete (FRC) has been proven to be an effective approach. In practice, such fibers include steel fibers, polyvinyl alcohol (PVA) fibers, polyacrylonitrile (PAN) carbon fibers and asbestos fibers, with the length scale ranging from centimeters to micrometers. When advancing such technique down to the nanoscale, it is noticed that carbon nanotubes (CNTs) are stronger than other fibers and can provide a better reinforcement to concrete. In the last decade, CNT-reinforced concrete attracts a lot of attentions in research. Despite high cost of CNTs at present, the growing availability of carbon materials might push the usage of CNTs into practice in the near future, making the reinforcement technique of great potential. A review of existing research works may constitute a conclusive reference and facilitate further developments. In reference to the recent experimental works, this paper reports some key evaluations on CNT-reinforced cementitious materials, covering FRC mechanism, CNT dispersion, CNT-cement structures, mechanical properties and fire safety. Emphasis is placed on the interplay between CNTs and calcium silicate hydrate (C-S-H) at the nanoscale. The relationship between the CNTs-cement structures and the mechanical enhancement, especially at a high-temperature condition, is discussed based on molecular dynamics simulations. After concluding remarks, challenges to improve the CNTs reinforcement technique are proposed.

• Structural Engineering and Mechanics
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• 제61권5호
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• pp.577-592
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• 2017

A computing procedure is presented to predict the ultimate behavior of prestressed beams under torsion. This computing procedure is based on an extension of the Variable Angle Truss-Model (VATM) to cover both longitudinal and transversal prestressed beams. Several constitutive relationships are tested to model the behavior of the concrete in compression in the struts and the behavior of the reinforcement in tension (both ordinary and prestress). The theoretical predictions of the maximum torque and corresponding twist are compared with some results from reported tests and with the predictions obtained from some codes of practice. One of the tested combinations of the relationships for the materials was found to give simultaneously the best predictions for the resistance torque and the corresponding twist of prestressed beams under torsion. When compared with the predictions from some codes of practice, the theoretical model which incorporates the referred combination of the relationships provides best values for the torsional strength and leads to more optimized designs.

• Journal of Yeungnam Medical Science
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• 제21권2호
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• pp.167-176
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• 2004

Background: Electromagnetic fields (EMF) are ubiquitous in modern society including medical field. As the technology of medical instruments and telecommunications has developed rapidly, it has influenced on our lives in many ways. Modern medical practice requires high quality medical equipments, which have a great deal of electromagnetic interference and susceptibility. The purpose of this study were to evaluate electromagnetic condition under usual clinical condition and to suggest a practical guideline in general hospital. Materials and Methods: The actual state of the electromagnetic interference in the medical field was studied under usual clinical conditions including operating rooms, intensive care units, magnetic resonance imaging unit, and hyperthermia unit. Results: There was considerable noise as a result of electromagnetic fields from medical equipments including electrosurgical units and hyperthermia unit, and cellular phones, which could induce serious functional derangements of functioning medical devices. Conclusion: It will be necessary to evaluate the individual electromagnetic situations under various medical conditions and to define a limited zone for cellular phone as well as reposition medical equipments to secure a safer medical practice and to minimize electromagnetic interference.

• 공학교육연구
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• 제4권1호
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• pp.88-98
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• 2001

이 논문은 공업 고등학교의 활성화와 효율화를 위한 새로운 모델로서 학교 자체의 독립성과 다른 학교와의 연계성을 같이 가지고 있는 지능적인 분산 포탈로서의 네트워크 모델을 제안하고 있다. 특히 실습이 많은 공업고등학교에서 동영상 화면을 가지고 있는 시뮬레이션을 무리 없이 활용하기 위해서는 자체의 인트라넷 기능을 수행하면서 필요에 따라 여러 수업 자료를 데이터 베이스로 구축하고 여러 학교가 필요한 자료들을 수업 외의 시간에 학교 데이터 베이스에 적재하여 학내 인트라넷에서 수업시간에 활용할 수 있는 방안을 언급하고 있다. 이러한 구조는 방대한 분산형 데이터 베이스의 활용과 학교 자체의 독립적인 특징을 살릴 수 있어, 물리적인 공업고등학교의 모습과 논리적인 사이버 공업고등학교의 모습이 병합될 수 있을 것이라고 제안하고 있다.

• 한국실내디자인학회논문집
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• 제21권5호
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• pp.227-236
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• 2012

In order to discuss identity of Interior Design as an academic study, I analyzed educational objectives and curriculums of Interior Design in tertiary educational institutions. To this end, I surveyed 83 colleges and categorized those colleges based on their school system and academic field where the college is included. First, according to the school system I classified them into 2-, 3-, 4-year course. Then, I categorized each of them into subcategories based on their fields; 2 year course into Design field and Construction Engineering field, 3 year course into Construction, Engineering and Design, 4 year course into Design, Life Science, Engineering and Construction. Referring to a Classified table of majors and fields by KIID, I reorganized them into ten big categories: (1)Design Theory (2)Design Technique (3)Interior Composition Elements (4)Basic Practice (5)Advanced Practice (6)Psychology and Behaviour (7)Design Management (8)History of Interior Design (9)Digital Design (10)Communication. The afore-mentioned ten curriculum categories show characteristics formed by composition in each school system. The curriculum categories in school system had differences in composition depending on each field. By examining similarities and differences among them, I concluded attributes of each field. I hope the result of this study can contribute to consistent study to establish and develop the academic identity of Interior Design.

• 품질경영학회지
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• 제33권2호
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• pp.74-86
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• 2005

The project objectives, called critical-to-quality (CTQs) in six sigma, should be defined to faithfully reflect the customer requirements. The identification of such a set of CTQs, which is currently done using brainstorming in practice, is a challenging task. Notwithstanding the rapid growth of the six sigma literature, development of a systematic procedure for identifying CTQs has scarcely been addressed. This paper proposes a systematic method for generating CTQ candidates based on the given voice of the customer in the DFSS/C (Design for Six Sigma / Commercial) context. By providing a step-by-step procedure, the proposed method ensures that all the important CTQ candidates are identified and subjective judgments are minimally required. Hence, the shortcomings associated with the existing practice based on brainstorming can be effectively overcome. The unique characteristics of the proposed method are also demonstrated via a case study.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2004년도 춘계학술발표대회논문집
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• pp.709-713
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• 2004

This Paper Presents an Internet-based Java self-learning educational system which consists of a management system named Java Web Player (JWP) and creative multimedia contents fer Java language. The JWP Is a Java application program free from security problems by the Java Web Start technologies that supports an Integrated learning environment including three Important learning Procedures: Java concept learning Process, Programming practice process and assessment process. This JWP enables the learners to achieve efficient and Interesting self-learning since the learning process is designed to enhance the multimedia capabilities on the basis of various educational technologies. On-line voice presentation and its related texts together with moving images are synchronized for efficiently conveying creative contents to learners. Furthermore, a simple and useful compiler is included in the JWP fur providing user-friendly language practice environment enabling such as coding, editing, executing and debugging Java source files on the Web. The assessment process with various items helps the learners not only to increase their academic capability but also to appreciate their current degree of understanding. Finally, simple multiple choices are given suddenly to the learners while they are studying through the JWP and the test results are displayed on the message box. The proposed system can be used for an efficient tool for learning system on the Web.

• The Journal of Asian Finance, Economics and Business
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• 제2권2호
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• pp.13-18
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• 2015

In this paper the DRC model is presented for solving multi objective problem. The proposed model is a combination of data envelopment analysis, Cuckoo algorithm and the response surface method. Due to reasons like costs, time and irreversible damages, it is not possible to analyze each and every one of the proposed models in practice, so the simulation is used. Since the number of experiments for simulation process is high then the optimization has gone to practice and directs the simulation process. The response surface method is used as one of the approaches of simulation optimization. Furthermore, data envelopment analysis is used to consider several response surfaces as efficiency response surface. Then this efficiency response surface is solved by Cuckoo algorithms. The main advantage of DRC model is to make one efficiency response surface function instate of multi surface function for every output and also using the advantages of Cuckoo algorithms. In order to demonstrate the effectiveness of the proposed approach, the branches of Refah bank in Mashhad is analyzed and the results are presented.

• 대한안전경영과학회지
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• 제19권4호
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• pp.189-208
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• 2017

This study is for figuring out major components of construction quality infrastructure and suggesting improvement plan by benchmarking global best practice model and analyzing gap between the model and sample practice. Based on improvement plan, researcher could derive major characters and components of construction quality infrastructure, and also about the priority among core competency components of construction quality experts. The result showed that the 'human resource' was ranked the best priority followed by 'method' 'environment', 'equipment' among major characters and components of construction quality infrastructure. Also, for core competency components of construction quality experts, 'number of years in work places' was the best priority, and the 'professional knowledge on engineering' was another priority ranked. Far from general perception on competency components, 'academic education' ranked the last. It may allude that the current education system in this country is not effective in developing competency of quality engineers. In summary, this study shows professionalism of quality engineer is the most important thing in all the components.

• 실천공학교육논문지
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• 제9권1호
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• pp.41-48
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• 2017

본 논문에서는 기초 디지털 논리 회로 실습 교육 과정을 설계하기 위해, 디지털 출력을 갖는 아두이노 프로그래밍을 통한 디지털 논리회로 제어 방법을 제안하였다. 디지털 논리회로와 아두이노 프로그래밍 실습은 국내 교육과정의 고등학교 및 대학교의 공학 계열 학과에서 필수 교육과정으로 지정하고 있다. 하지만 실제 실습에는 디지털 논리회로와 아두이노 프로그래밍이 결합된 예제가 부족하고, 디지털 논리회로를 설계하고 오실로스코프 보다 저가의 비용으로 실험할 수 있는 교육 과정이 부족하다. 이에 본 논문에서는 이 문제를 해결하는 디지털 출력 명령을 통한 아두이노 프로그래밍을 통해, 디지털 논리회로를 제어하고 실습해보는 한 학기 기간의 기초 디지털 논리 회로 실습 교육 과정을 제안하였다.