• 제목/요약/키워드: CAI test

검색결과 140건 처리시간 0.025초

3차원 직조형 열가소성수지 복합재료 제조 및 특성화 (Fabrication and Characterization of 3D Woven Textile Reinforced Thermoplastic Composites)

  • 홍순곤;변준형;이상관
    • Composites Research
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    • 제16권2호
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    • pp.33-40
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    • 2003
  • 본 논문은 열경화성수지 적층 복합재료의 낮은 충격 특성과 층간 분리 현상을 개선하고자 열가소성 수지 및 3차원 직조 프리폼을 사용한 복합재료 제조와 물성 특성화에 대한 것이다. 새로운 기술인 co-braiding 성형법으로 열가소성 PEEK 섬유와 탄소섬유를 혼합한 섬유를 제조하였으며. 층간 분리 억제 특성을 현저하게 향상시키기 위하여 두께방향의 섬유를 가지는 3차원 직조형 프리폼을 제조하였다. 혼합섬유로 제조된 프리폼에 열성형 공정을 적용함으로써 열가소성 복합재료를 제조하였으며. 혼합섬유의 PEEK 섬유는 용융온도에서 용융되어 탄소섬유 사이로 함침이 완벽하게 일어남을 확인하였다. 또한, APC-2/AS4 프리프레그를 사용한 준 등방 적층 복합재료를 제조하여 3차원 직조형 열가소성 복합재료의 특성과 비교하였다. 항공기 소재로서의 적용 가능성을 알아보기 위하여 open hole 인장시험, 충격시험, 및 충격 후 압축시험 등의 결과를 통하여 3차원 직조형 열가소성 복합재료는 기존의 적층 복합재료보다 우수한 내 충격성 손상허용치를 가짐을 보였다.

Effects of Mulligan's Mobilization with Movement on Talofibular Interval in Subjects with Chronic Ankle Instability

  • Koh, Eun-Kyung;Jung, Do-Young
    • The Journal of Korean Physical Therapy
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    • 제28권5호
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    • pp.303-307
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    • 2016
  • Purpose: This study was conducted to determine the effects of Mulligan's mobilization with movement (MWM) on changes in the talofibular interval in the sagittal plane in subjects with chronic ankle instability (CAI). Methods: Sixteen subjects with chronic ankle instability participated in this study. The talofibular intervals were measured from US images, and the weight-bearing lunge test was used to assess dorsiflexion of the ankle joint. Each dependent variable were measured on the both affected side and sound side in three trials in pre- and post-MWM. Dependent variables were examined with a two-way mixed-design analysis of variance (ANOVA). The two factors were side (sound side versus affected side) and intervention (pre- versus post-intervention). For post hoc analysis, paired t-tests were performed to compare the dependent variables. A p<0.05 was considered to indicate significance. Results: Dorsiflexion and talofibular interval differed significantly pre- and post-intervention (p<0.05). Post-hoc analysis revealed that the talofibular interval post-MWM was significantly less than that pre-MWM on the both the affected and sound side (p<0.05). The ankle dorsiflexion in the post-MWM group was significantly greater than that in the pre-MWM group on the affected side and the sound side (p<0.05). Conclusion: The Mulligan's MWM decreased the talofibular interval in subjects with CAI. These findings suggest that the MWM technique can change the position of the talus relative to the fibular in the weight bearing position.

Reducing Test Power and Improving Test Effectiveness for Logic BIST

  • Wang, Weizheng;Cai, Shuo;Xiang, Lingyun
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제14권5호
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    • pp.640-648
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    • 2014
  • Excessive power dissipation is one of the major issues in the testing of VLSI systems. Many techniques are proposed for scan test, but there are not so many for logic BIST because of its unmanageable randomness. This paper presents a novel low switching activity BIST scheme that reduces toggle frequency in the majority of scan chain inputs while allowing a small portion of scan chains to receive pseudorandom test data. Reducing toggle frequency in the scan chain inputs can reduce test power but may result in fault coverage loss. Allowing a small portion of scan chains to receive pseudorandom test data can make better uniform distribution of 0 and 1 and improve test effectiveness significantly. When compared with existing methods, experimental results on larger benchmark circuits of ISCAS'89 show that the proposed strategy can not only reduce significantly switching activity in circuits under test but also achieve high fault coverage.

Study on anchorage effect on fractured rock

  • Wang, Jing;Li, Shu-Cai;Li, Li-Ping;Zhu, Weishen;Zhang, Qian-Qing;Song, Shu-Guang
    • Steel and Composite Structures
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    • 제17권6호
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    • pp.791-801
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    • 2014
  • The effects of anchor on fractured specimens in splitting test are simulated by DDARF method, the results of which are compared with laboratory test results. They agree well with each other. The paper contents also use the laboratory model test. The main research objects are three kinds of specimens, namely intact specimens, jointed specimens and anchored-jointed specimens. The results showed that with the joint angle increased, the weakening effects of jointed rock mass are more obvious. At these points, the rock bolts' strengthening effects on the specimens have become more significant. There is a significant impact on the failure modes of rock mass by the joint and the anchorage.

인터넷을 이용한 간호학 교육 프로그램 개발 및 효과분석 -간호정보학을 중심으로- (The Development and Effect Analysis of an Internet Based Nursing Program: Application to Nursing Informatics)

  • 염영희
    • 대한간호학회지
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    • 제30권4호
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    • pp.1035-1044
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    • 2000
  • The purpose of this study was to develop and evaluate an internet based program for nursing informatics. The course subject, Nursing Informatics, was made by a computerized instructional module using the internet. The program was developed after taking into consideration the level of competence and knowledge in the subjects. It was based on 10 steps of the CAI module developed by Alessi and Trollip. The subjects consisted of 76 junior nursing students taking a Nursing Informatics course. Two sets of questionnaires were used for this study. First, a questionnaire was administered to 76 students to collect general information on their experience while using computers and the internet. Secondly, another questionnaire was administrated to 76 students after they took the course. They were asked to evaluate the program in terms of easiness of use, precision of contents, freshness of contents, motivation in learning, effectiveness of learning, enhancement of communication, precision of screen, and interest in the contents. IDs and passwords were given to the students. The students were asked to write their IDs and passwords when they connected to Nursing Informatics (http://hallym.ac.kr/~yhyom/ inform.html). They were led the menu page which was categorized into 8 icons (i. e., syllabus, lecture notes, quick test, Q & A board, assignment, on-line test, related web sites and mailing lists) after confirming their IDs and passwords. The students' responses were very positive. This program was a very useful in increasing the effectiveness of learning and motivation in the students. Suggest to be use for other nursing courses.

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Significance and Application of Digital Breast Tomosynthesis for the BI-RADS Classification of Breast Cancer

  • Cai, Si-Qing;Yan, Jian-Xiang;Chen, Qing-Shi;Huang, Mei-Ling;Cai, Dong-Lu
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권9호
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    • pp.4109-4114
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    • 2015
  • Background: Full-field digital mammography (FFDM) with dense breasts has a high rate of missed diagnosis, and digital breast tomosynthesis (DBT) could reduce organization overlapping and provide more reliable images for BI-RADS classification. This study aims to explore application of COMBO (FFDM+DBT) for effect and significance of BI-RADS classification of breast cancer. Materials and Methods: In this study, we selected 832 patients who had been treated from May 2013 to November 2013. Classify FFDM and COMBO examination according to BI-RADS separately and compare the differences for glands in the image of the same patient in judgment, mass characteristics display and indirect signs. Employ Paired Wilcoxon rank sum test was used in 79 breast cancer patients to find differences between two examine methods. Results: The results indicated that COMBO pattern is able to observe more details in distribution of glands when estimating content. Paired Wilcoxon rank sum test showed that overall classification level of COMBO is higher significantly compared to FFDM to BI-RADS diagnosis and classification of breast (P<0.05). The area under FFDM ROC curve is 0.805, while that is 0.941 in COMBO pattern. COMBO shows relation of mass with the surrounding tissues, the calcification in the mass, and multiple foci clearly in breast cancer tissues. The optimal sensitivity of cut-off value in COMBO pattern is 82.9%, which is higher than that in FFDM (60%). They share the same specificity which is both 93.2%. Conclusions: Digital Breast Tomosynthesis (DBT) could be used for the BI-RADS classification in breast cancer in clinical.

멀티미디어 저작도구 카스에 의한 수치데이터 표현에 관한 연구 (A Study on the Expression of Numerical Data by the KAS Multimedia Tool)

  • 김상호;이영욱
    • 한국컴퓨터정보학회논문지
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    • 제4권3호
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    • pp.1-7
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    • 1999
  • 본 연구는 고등학교 '전자계산일반' 교과의 '자료표현' 단원 중 칠판수업을 통해서는 학습자들이 좀 지루하고 이해하기 어려운 수치 데이터 표현의 효과적인 교수-학습을 위하여 멀티미디어 저작도구 카스(KAS)를 사용하여 멀티미디어 프로그램을 반복학습형. 개인교수형, 교수적 게임형이 복합된 코스웨어로 설계하고 구현하였다. 기존 컴퓨터 보조수업의 단점인 텍스트와 이미지 위주의 구성에서 탈피하여 텍스트뿐만 아니라. 음향 영상, 애니메이션 등의 다양한 매체를 결합한 학습이 가능하도록 하였다. 진법 전환이나 수치 데이터의 표현같이 흐름을 중시하는 학습 부문은 애니메이션으로 처리하여 학습자들이 스스로 학습 진행과정을 눈으로 확인 할 수 있도록 함으로써 학습효과를 높였으며 단원별 학습이 끝날 때마다 연습문제 풀이 화면을 두어 학습내용 이해도를 측정할 수 있게 하였다. 본 연구자료를 충청북도 소재 음성고등학교의 학습현장에 적용한 결과 학습효과가 향상되었음이 통계학적 검정 결과 입증되었다.

Experimental study on shear capacity of circular concrete filled steel tubes

  • Xiao, Congzhen;Cai, Shaohuai;Chen, Tao;Xu, Chunli
    • Steel and Composite Structures
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    • 제13권5호
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    • pp.437-449
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    • 2012
  • Concrete filled steel tube (CFST) structures have recently seen wide use in China, but studies of the shear problem of CFST are inadequate. This paper presents an experimental study on the shear capacity of circular concrete filled steel tube (CCFT) specimens with and without axial compression force. Shear capacity, ductility, and damage modes of CCFTs were investigated and compared. Test results revealed the following: 1) CCFTs with a small shear span ratio may fail in shear in a ductile manner; 2) Several factors including section size, material properties, shear span ratio, axial compression ratio, and confinement index affect the shear capacity of CCFTs. Based on test results and analysis, this paper proposes a design formula for the shear capacity of CCFTs.

Detection and Recognition of Illegally Parked Vehicles Based on an Adaptive Gaussian Mixture Model and a Seed Fill Algorithm

  • Sarker, Md. Mostafa Kamal;Weihua, Cai;Song, Moon Kyou
    • Journal of information and communication convergence engineering
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    • 제13권3호
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    • pp.197-204
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    • 2015
  • In this paper, we present an algorithm for the detection of illegally parked vehicles based on a combination of some image processing algorithms. A digital camera is fixed in the illegal parking region to capture the video frames. An adaptive Gaussian mixture model (GMM) is used for background subtraction in a complex environment to identify the regions of moving objects in our test video. Stationary objects are detected by using the pixel-level features in time sequences. A stationary vehicle is detected by using the local features of the object, and thus, information about illegally parked vehicles is successfully obtained. An automatic alarm system can be utilized according to the different regulations of different illegal parking regions. The results of this study obtained using a test video sequence of a real-time traffic scene show that the proposed method is effective.

Effect of electrochemical treatment on consolidation of soft clay

  • Li, Xiaobing;Yuan, Guohui;Fu, Hongtao;Wang, Jun;Cai, Yuanqiang
    • Geomechanics and Engineering
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    • 제15권4호
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    • pp.957-964
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    • 2018
  • In this study, a method of electrochemical consolidation is applied. This method utilizes electro-osmosis, which is an effective ground improvement technique for soft clays, and soil treatment using lime, which is the oldest traditional soil stabilizer. The mechanism of lime treatment for soil involves cation exchange, which leads to the flocculation and agglomeration. Five representative laboratory tests-an electro-osmotic test and four electrochemical tests with various proportions of lime-were performed on dredged marine clay. The objectives of this study are to investigate the effect of electrochemical treatment and to determine the optimum dose for optimal consolidation performance of dredged marine clay. The results show that a better consolidation effect was achieved in terms of current, temperature, and vane shear strength by using electrochemical treatment. The best results were observed for the electrochemical test using 4% lime content.