Effects of Cooling Rate on the Microstructure and Tensile Properties of Wire-Arc Additive Manufactured Ti–6Al–4V Alloy

Hui‑Jun Yi,Jin‑Woo Kim,Young‑Lak Kim,Sangyong Shin 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.8

Wire-arc additive manufacturing has emerged as a technology that could replace the conventional manufacturing processof titanium alloys. However, it produces a coarse β grain, which can accumulate via several deposited materials, resulting isstrong texture and anisotropy. To investigate potential solutions, the effects of the cooling rate on the resulting microstructureand tensile properties were studied. The cooling rate of the deposited materials was adjusted by interpass temperaturecontrol. Under rapid cooling, fine α + α′ grain with a low aspect ratio were observed and tensile and hardness propertieswere also improved.

우관상동맥 개구부 완전 폐쇄가 동반된 대동맥 판상부 협착증 1례

임상현,김종진,김희열,진승원,전희경,노태호,채장성,김재형,홍순조,최규보,윤정섭,김치경 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.4

불안정 지지면을 이용한 운동 프로그램이 뇌졸중 환자의 균형에 미치는 효과

이지연,김용수,김진섭,박진현,최윤희,전덕훈,김경 대구대학교 특수교육재활과학연구소 2010 再活科學硏究 Vol.28 No.1

본 연구의 목적은 뇌졸중 환자의 재활을 위하여 불안정 지지면을 이용한 운동 프로그램이 균형 능력과 운동 기능 능력에 미치는 효과를 알아보고자 실시하였다. 불안정 지지면의 이용한 치료는 임상적으로 뇌졸중으로 인한 편마비 환자뿐만 아니라 스포츠 손상 및 노인들의 질환 등 다양한 병인을 가진 환자들의 치료에 이용되고 있다. 대부분의 뇌졸중 환자들은 재활 훈련을 할 수 있는 병원이나 기관에서 치료를 받을 때에 지지면의 차이를 제공함으로써 보다 더 안정한 지지면에서 적응할 수 있는 방법이 요구되고 있다. 하지만, 아직도 불안정 지지면을 이용한 구체화된 치료적 운동 방법과 객관적 평가에 대한 연구가 미비한 실정이다. 이러한 문제점을 해결하기 위하여 최근 뇌졸중 환자의 불안정 지지면과 이론적 근거를 바탕으로 한 운동 프로그램에 대한 연구가 더욱 필요하다. 본 연구에서는 실험군과 대조군이 같은 운동 프로그램을 적용하였을 때, 두 그룹 간에서 나타나는 균형 향상과 운동 기능 향상에 어떠한 효과를 주는지 살펴보고자 하였다. The purpose of this article was to study the effect of the exercise programme that uses the unstable supporting surface to rehabilitate cerebrovascular patients on balance ability and exercise function ability. The therapy is being clinically used for the patients with diverse pathological factors such as hemiplegia caused by CVA, sports injury, and diseases in the elderly. when most patients with CVA are treated in the hospital or institute that can provide rehabilitation training, they need to be given the way to adjust more stable surpporting surface by being provide with various stages of surface. However, the actual therapeutic exercises is still needed and the study for objective assessments wants conducting. To solve these problems, the study of unstable surface exercise programmes based on the evidences recently need to be made for the patients with CVA. in this study, we intend to look into what effects on the balance improvement and the exercise function are different from the experimental group to the control group with the same programme applied to the two groups.

하약골 수조작술에 의한 폐구성 과두걸림 환자의 치료

김진환,김희정 大韓顎顔面成形再建外科學會 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.1

In general, treatment of the patients with closed lock divides into a conservative and a surgical treatment. Surgical treatment has been often applied in case that occlusal splint therapy was not effective on the patient with closed lock. In recent, some clinicians reported good results with mandibular manipulation. Three patients complained limitation of month opening-(mean mouth opening was 22.3mm) and TMJ pain. Articular discs were displaced anteriorly on MRI. Two patients didn't improve the symptoms with long term occlusal splint therapy. We applied mandibular manipulation after injection with 2% lidocaine into the upper joint space of the affected TMJ and directly inserted occlusal splint to all patients. At the follow-up check, mean mouth opening was 41.7mm. TMJ pain decreased, condyle and disc relationship was improved functionally on MRI.

식품 기준·규격의 합리적 관리 ·운영에 관한 연구(Ⅰ) : 두부,식용유지, 전분의 분말상 원료에 관하여 Powdered marerials of Tofu, Edible oil, Starch

김희연,홍진환,박혜경,한상배,박종석,이은주,이정성,송경희,최은희,최영준,소경아,성영제,이주엽 식품의약품안전청 2000 식품의약품안전청 연보 Vol.4 No.-

본 연구는 분말상 원료(전분, 대두분)의 저장유통시 품질변화를 건전성과 안전성 측면에서 검토하여 식품의 기준 ·규격 설정f.」 합지적으로 반영하고자 하였다. 전분과 패두분의 이물을 검사하고, 2종 대두분(중국산, 미국산)을 ?0일간 IS'c와 30t에 저장하면서 성상, 수분, 산가, 과산화물가, 지방산 조성,아플라톡신 BB의 생성여부를 분석하였다. 중국산 대두분 30'』 저장군에서 50일 이후 곰팡이가 발생한 것 이외에 모든 시료에서 양호한 성상을 나타내었고, 전분과 대두닥 모든 시료에서 이물은 검출되지 않았다. 산가는 중국산과 미국산 시료간에 편차를 보여 증국산 30"C, 50일 저장시료에서 약 10배끙도 증가하였고, 과산화물가는 저장 90일후 15'E 저장군은 약 2.3배, 30'c 저장군은 3배정도 증가하였다. 대두분의 주요 지방산은 linoleic acidf18. 2), oleic acid(18 : 1), palmitic acid(16 : 0)이었으며, 3개월 저장에 따른 지방산 함량의 변화는 미미하였다. 아플라톡신 B₁은 모든 시료에서 검출되지 않았다. The objective of this study was to investigate auality changes of type raw materials(starch, soy flour) during various storage conditions. Starchflour(source of China, U.S.A) were slfred under two temperature(15'C, 30'c) forSensory evaluation, (o.reign material test, moisture content, acid value, peroxide ualue,composition, aflatorin Bi were analyzed. China soy flour(stor·ed 30'f) was contaminated by fungj on 50 days. Except for soy flour contardnated by fungi, sensory characteristics were not changed and foreign mater;als were notdetected. Acid value of China soy flour(stored at 30'C, 90 days) was about 10 times higherlevel before storage and acid value was more influenced by source(China, USA). Peroxide valuewas in proportion with the storage period slightly. The major fatty acid of soy flour waslinoleic acid(18 . 2), an(3 the change of fatty acid composition was not observed. Aflatoxlrl Blwas not detected.

효과적인 다차원 분석을 지원하는 스트레드시트 방식의 OLAP 인터페이스 설계 및 구현

윤민희,김진호,문양세 강원대학교 정보통신연구소 2006 정보통신논문지 Vol.10 No.-

OLAP systems support effectively data analysis over a large volume of business data to make decisions for an enterprise. In order to process data analysis efficiently, OLAP systems pre-compute the summary of business data over various dimensions and store them into data warehouses. Several specialized tools have been developed to display and to browse the results of complex analytical queries on data warehouses. In this paper, we developed a spreadsheet-like tool to support OLAP operations and to browse the results of analytical queries. Spreadsheet is one of the most popular and user-friendly data analysis tool. It also has lots of advantages, which is interactive, easy to learn, etc. Thus this paper implemented an OLAP tool using spreadsheet-style interface to analyze large OLAP data on World-Wide Web. Through this tool, users can process OLAP activities easily and effectively by using the same ways as well-known shreadsheet tools like Microsoft Excel.

효과적인 다차원 분석을 지원하는 스프레드시트 방식의 OLAP 인터페이스 설계 및 구현

윤민희,김진호,문양세 강원대학교 정보통신연구소 2006 정보통신논문지 Vol.10 No.-

OLAP systems support effectively data analysis over a large volume of business data to make decisions for an enterprise. In order to process data analysis efficiently, OLAP systems pre-compute the summary of business data over various dimensions and store them into data warehouses. Several specialized tools have been developed to display and to browse the results of complex analytical queries on data warehouses. In this paper, we developed a spreadsheet-like tool to support OLAP operations and to browse the results of analytical queries. Spreadsheet is one of the most popular and user-friendly data analysis tool. It also has lots of advantages, which is interactive, easy to learn, etc. Thus this paper implemented an OLAP tool using spreadsheet-style interface to analyze large OLAP data on World-Wide Web. Through this tool, users can process OLAP activities easily and effectively by using the same ways as well-known shreadsheet tools like Microsoft Excel.

DiffServ 환경에서 Mobile Xcast 지원에 관한 연구

배진호,김태수,이광휘 국립7개대학공동논문집간행위원회 2003 공업기술연구 Vol.3 No.-

In the third generation of mobile computing environment, the applications that are compatible with small members of group in which the applications join the multicast sessions such as Internet phone, video conference and networked games are more prevalent. However, since the traditional multicast mechanisms supporting the mobile computing are suitable for large members of group in the multicast session, we need to consider a new mechanism to complement them. Therefore, in this paper we suggest a new multicast model that adopted explicit multicast(xcast), which has more gradual deployment with legacy Internet backbone. This proposed model is cost-effective and more scalable and guarantees the QoS in mobile computing.

고속의 GaAs SRAM 을 위한 새로운 센스 앰프의 설계 연구

조희철,김선옥,이웅호,윤진섭,이진구 동국대학교 산업기술대학원 1993 산업기술논문집 Vol.1 No.-

A new sense amplifier is designed in order to realize high-speed GaAs SRAM's. The Schematics are similar to "a source coupled differential amplifier" execept that two analyzed using basic FET current equations. The transconductance of the new sense amplifier is approximately 3.5 times larger than that of the conventional sense amplifier. Output high voltage is reduced to about 0.64V, therefore, the time which reached V_(max) are reduced also. The simulation results show that the access time of 0.9ns and the power dissipation of 12.2mW are achieved in GaAs 16bit SRAM's.

Sol-Gel법을 이용한 Silica Membrane의 제조 공정에 관한 조사연구

이진휘,이준,김화중 서울産業大學校 1990 논문집 Vol.32 No.1

졸 -겔 공정에 대한 일반적인 문헌들을 검토하였다. 이와같은 문헌들을 성공적으로 적용하려면 공정에 대한 여러가지 단계와, 영향을 미치는 인자들에 관한 체계적인 이해가 먼저 요구된다. 겔화하는 동안 구조 및 미세구조의 전개에 영향을 미치는 몇가지 인자와 더불어 건조 및 열처리 조건을 조사하였다. 혼합물, 다공성 고체 및 코팅분야에 적용하기 위한 몇가지 예들을 기술하였다. 현재 이 분야의 발전에 기여할 새로운 응용기회는 많다. The general informations of the sol-gel process are reviewed. Successful applications are dependent on sufficient scientific understanding of the various stages and factors of the process. A number of factors governing the development of the structure and microstructure during gelation and subsequent drying and firing conditions are mentioned. Examples are described for applications in the areas of composites, porous solids and coatings. Opportunities for many new applications are presently available for exploitations.