• 제목/요약/키워드: Subject Response Test

검색결과 166건 처리시간 0.027초

Effect of bidirectional internal flow on fluid.structure interaction dynamics of conveying marine riser model subject to shear current

  • Chen, Zheng-Shou;Kim, Wu-Joan
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제4권1호
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    • pp.57-70
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    • 2012
  • This article presents a numerical investigation concerning the effect of two kinds of axially progressing internal flows (namely, upward and downward) on fluid.structure interaction (FSI) dynamics about a marine riser model which is subject to external shear current. The CAE technology behind the current research is a proposed FSI solution, which combines structural analysis software with CFD technology together. Efficiency validation for the CFD software was carried out first. It has been proved that the result from numerical simulations agrees well with the observation from relating model test cases in which the fluidity of internal flow is ignorable. After verifying the numerical code accuracy, simulations are conducted to study the vibration response that attributes to the internal progressive flow. It is found that the existence of internal flow does play an important role in determining the vibration mode (/dominant frequency) and the magnitude of instantaneous vibration amplitude. Since asymmetric curvature along the riser span emerges in the case of external shear current, the centrifugal and Coriolis accelerations owing to up- and downward internal progressive flows play different roles in determining the fluid.structure interaction response. The discrepancy between them becomes distinct, when the velocity ratio of internal flow against external shear current is relatively high.

MIL-S-901D 부유식 충격시험기의 충격응답 해석 (Shock Response Analysis of A MIL-S-901D Floating Shock Platform)

  • 권정일;이상갑;정정훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
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    • pp.761-765
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    • 2001
  • Shock responses of the MIL-S-901D standard floating shock platform("SFSP") subject to underwater explosions(UNDEX) are analyzed by using the LS-DYNA/USA. For the analysis, surrounding fluids as well as the SFSP are included in a 3D FE model to consider the cavitation effects of the UNDEX shock wave. The calculated results are compared with the existing test results and it is confirmed that the analysis results predict accurately the shock behaviors of the SFSP.

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Cracking behavior of RC shear walls subject to cyclic loadings

  • Kwak, Hyo-Gyoung;Kim, Do-Yeon
    • Computers and Concrete
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    • 제1권1호
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    • pp.77-98
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    • 2004
  • This paper presents a numerical model for simulating the nonlinear response of reinforced concrete (RC) shear walls subject to cyclic loadings. The material behavior of cracked concrete is described by an orthotropic constitutive relation with tension-stiffening and compression softening effects defining equivalent uniaxial stress-strain relation in the axes of orthotropy. Especially in making analytical predictions for inelastic behaviors of RC walls under reversed cyclic loading, some influencing factors inducing the material nonlinearities have been considered. A simple hysteretic stress-strain relation of concrete, which crosses the tension-compression region, is defined. Modification of the hysteretic stress-strain relation of steel is also introduced to reflect a pinching effect depending on the shear span ratio and to represent an average stress distribution in a cracked RC element, respectively. To assess the applicability of the constitutive model for RC element, analytical results are compared with idealized shear panel and shear wall test results under monotonic and cyclic shear loadings.

인문계 남녀고등학생의 스트레스 인지, 자아존중감, 스트레스 반응간의 관계 연구 (A Study of the Relationship between Perceived Stress, Self Respect & Stress Response in High School Students)

  • 석민현;박정원
    • 지역사회간호학회지
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    • 제11권2호
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    • pp.556-565
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    • 2000
  • The purpose of this study was to investigate the relationship between perceived stress. self respect & stress response of high school students to provide the basic data for nursing intervention programs in order to manage stress in students. The subject of this study was 279 students (male; 179. female; 100) in high school. Seoul. Korea. during the period from July. 2000. The instruments for this study was a stress management scale developed by Park Young Ae(l996), a self respect scale by Coopersmith (1967) and a physical. emotional response scale to stress by Ro, Jae Hak(1991). The data was analyzed by descriptive statistics, t-test. Pearson correlation coefficient. The results of analysis were as follows: 1) Total perceived stress between males & females didn't show a significant difference but subgroups of stress, 'parent' & 'friend' showed significant differences. Male students were experienced in 'parent' stress than females and female students were more experienced in 'friend' stress than males. 2) A significant negative correlation was revealed between perceived stress & self respect. 3) A significant positive correlation was revealed between self respect & stress response. The result of this study lead us to the suggestion that for high school students. the development of stress management methods for improving self respect should be expanded.

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The Influence of Likert Scale Format on Response Result, Validity, and Reliability of Scale -Using Scales Measuring Economic Shopping Orientation-

  • Kim, Sae-Hee
    • 한국의류학회지
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    • 제34권6호
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    • pp.913-927
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    • 2010
  • This study investigates the influence of Likert scale formats such as the number of response categories and the inclusion of a mid-point from a methodological point of view using instruments that measure a fashionmarketing-related subject. Using a self-administered questionnaire, 201 respondents rated their economic clothing shopping orientation on three formats of scales that differed only in the number of response categories (ranging from 5 to 7) from February 8 to February 12, 2010. Descriptive statistics, Spearman's rank order correlation, t-test, exploratory factor analysis, confirmatory factor analysis, Pearson's correlation, and Cronbach's alpha were used in the analysis. The results are as follows. First, three scale formats were generally suitable for use due to validity and reliability. Second, the response results varied with the number of categories and the inclusion of a mid-point, although the differences were statistically insignificant (with only a few cases that differed). Third, construct validity was more secure in scales with fewer categories, whereas convergent and discriminant validity was generally good in all scale formats. Fourth, reliability coefficients were higher in scales with more categories. Fifth, the number of categories was of greater importance to instrument design than the inclusion of a mid-point. Implications for appropriate scale designs are suggested in this study.

기술ㆍ가정교과 의생활 영역에 대한 여고생들의 학습 요구

  • 조은영
    • 한국가정과교육학회지
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    • 제15권4호
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    • pp.23-35
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    • 2003
  • The purpose of this research is to analyse the composition of theories and practical activities in clothing and textiles in Technologyㆍ Home economics textbooks in the 7th National Curriculum and find out learning requirement of students in the area. For this research, a survey was conducted using questionnaires with 280 high school students living in Daegu and the rate of response was 78.9%. The results of this study are as follows. 1. After analysing the curriculum of Practical Arts subject in elementary school and Technology´ Home Economics subject in secondary school, we could find out that more emphasis is put on practical activities in elementary school and high school. On the other hand, theories are considered more important in middle school. 2. Students have similar preference both for theories and for practical activities as a way of learning in class and show positive responses to practical activities unless they´re giving too much pressure as a part of performance test. 3. According to their learning requirement. several teaching-learning contents in clothing and textiles in Technology Home economics are selected such as materials,. clothes designs, how to set dressed well, how to make a reasonable purchase on clothes, and the process of manufacturing various clothes, etc. Therefore it would be desirable to provide the students with the learning opportunity to the extent where even the students who haven´t chosen the selected-advanced course can take part in class actively.

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외식산업 전문인력 양성에 관한 연구(공급자 관점에서) (A research study on the cultivation of professionals in the foodservice industry)

  • 윤지연;홍완수;김태희
    • 대한가정학회지
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    • 제45권1호
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    • pp.91-99
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    • 2007
  • The purpose of this study was to determine a is finding the process for the development of professionals in the foodservice industry. The Questionnaire used in this study was designed to measure the capabilities of professional foodservice employees, investigate the importance and accomplishments of curriculum of the major subject, and determine areas matters of the for improvement in the of field. It was distributed to 101 professors (include lecturers) of foodservice departments, from February 1 to 28, 2006. A total of 101 usable questionnaires were received amounting to a 100 percent response rate. Statistical data analysis was completed using SPSS Win(11.0) for frequency, t-test, one sample t-test, and IPA(importance performance analysis). The results were as is follows. Regarding the As regard capabilities of professional foodservice employees, they remarked that the fair values and creative thinking are the most important. Regarding the curriculum of the major subject, generally the importance degree is higher than the accomplishment degree. The areas improvement are as follows: development of curriculum, securing the excellent faculty, academic-industrial cooperation, expanding and improving the university facilities in university, and increasing the experience during the term.

의복원형의 외관과 맞음새를 위한 관능평가 방법에 대한 연구 (A Study on the Sensory Evaluation of Appearance and Fit for Basic Apparel Patterns)

  • 최미성
    • 한국의류학회지
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    • 제26권11호
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    • pp.1627-1637
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    • 2002
  • The objective of this study is to analyze the images of basic bodice apparel displayed on the PC monitor connected to digital camera, and to suggest a more efficient alternative method that enables the expert judge to evaluate the subject both traditional method and displayed images on the computer. Appearance evaluation has traditionally been assessed using subjective method dependent upon expertjudges' senses with the naked eye after direct observation of a living model. This research faces the new challenge focusing on the sensory evaluation of appearance for basic apparel patterns, which can overcome the space and time limitations of the traditional feet methods. A total fifteen basic bodice garment (3 types of $pattern\;{\times}\;5$ subject) were constructed with same fabrics. The appearance evaluation items consist of lg questions of upper torso. The image takes font, back and side view of the dressed subject with three different situations. Data was analyzed using percentiles, standard deviation T-test and ANOVA. Taken together, the present result of appearance evaluation through digital camera image shows that there is a significant difference ($p{\leq}.001$) in the response to the placement of the neckline, the waist & shoulder dart, the general ease of the bust & waist area, the side seam, the perpendicular of the waist hem and general acceptability between the above three different situations; the image in the condition of greenish yellow background with front light showed the highest score through all questions. These results depend on the kind of background colors with the light.

뇌-컴퓨터-인터페이스를 위한 EEG 기반의 피험자 반응시간 감지 (EEG-based Subjects' Response Time Detection for Brain-Computer-Interface)

  • 신승철;류창수;송윤선;남승훈
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제29권11호
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    • pp.837-850
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    • 2002
  • 본 논문에서는 인지적 긍정/부정 선택 과제의 수행 시 뇌파를 이용하여 피험자의 반응시간 RT(response time)를 예측하는 방법에 관하여 기술한다. 실험 task에서 피험자는 시각적 자극에 대한 반응, 문제의 해석, 손 움직임의 조절, 손동작 등과 관련된 뇌활동을 한다. 이와 같은 피험자의 정신상태의 변화를 CT(cut time), ST(selection time), RP(repeated period) 등을 정의하여 모델링하고, 선택시간 ST를 감지하여 피험자의 반응시간 RT를 예측한다. ST를 감지하기 위하여 측정한 뇌파로부터 $\alpha$, $\beta$, ${\gamma}$파를 분리하고, 공간적인 관계를 고려하여 설정한 4쌍의 전극들로부터 3가지의 특징들을 추출한다. 추출한 특징들을 분석하여 각 피험자별로 나타나는 상세 규칙(specific rule)과 공통적인 특징들로 구성된 일반 규칙(meta rule)들을 설정한다. 8명의 피험자를 대상으로 설정한 규칙들을 적용하여 평균 83%의 ST 감지 성공률을 보이고, ST 감지 이후 약 0.73초에서 RT가 나타나는 것을 보인다. 설정한 규칙들의 타당성을 검증하기 위하여 8명 중 2명의 피험자에 대해서 재실험을 하고, 이들 데이타에 적용한 결과를 보인다. 본 논문에서 제안한 방법을 기존의 인지적인 정신상태 판별을 위한 방법들이나 왼손/오른손 동작구분 방법들과 결합하여 사용할 경우 BCI를 위한 기반 기술로 활용될 것으로 기대한다.

중풍환자(中風患者)의 후유증(後遺症)에 따른 Stress 지각반응(知覺反應)에 대(對)한 조사연구(調査硏究) (A Study on the Stress Perception Response Following the Aftereffect in Poststroke Patients)

  • 박재현;류영수
    • 동의신경정신과학회지
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    • 제8권1호
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    • pp.151-165
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    • 1997
  • The primary purpose of this study was to assess the relation of stress perception and poststroke. This study was done on 50 stroke patients in hospital. According to activities of functional impairment, they were classified into walking disturbance, motor weakness, dysphagia, or reattack etc. The stress perception test(GARS Scles) and stress response assessment shows the follwing results. 1. On the distribution in the stroke 50 patients, For the majority group were male in sex, sixty inage, middle towns people in residence. 2. On the comprehensive GARS scale scores, It marked the higest scores thirty at age, merchandise or salesman on jobs, a city in residence. There was no signigicant difference in mean GARS Scales scores between males and females group, the left hemiplegia and the Rt hemiplegia. 3. On the comprehensive GARS Scale tests, Overall glogal stressor(G8) and sickness stresor(G4) marked the highest scores of all GARS Scales. 4. On the comparative assessment of each group's stress reponse test scores, zung-bu(中腑) was showed higher scores than the other group in oriental diagnosis and hemorrage was showed higher scores than the other group in western medical diagnosis. 5. On the comprehensive assessment of each group's stress reponse test scores, aphsia(不語) marked the highest scores in another disphagia group's. It marked the highest scores in another group's that banshinbulsoo(半身不遂) as regards as hemiplegia generally. Standing disability is the higher scores than another group's walking alone or assist, and standing alone. 6. Secondary attack is the highest scores of all reattack stroke on the stress repones test. 7. Comparing and analyzing the GARS Scale total scores and GARS Scale subject fator at stroke, we found that sickness stressor and fininial stressor is showed the highest correlated to stress response fowlloing stroke. With those results, we can see that functional impairment following stroke is correlated to stress perception and reponse. In the furture studies using, we hope that the findings the study would have clinical relevance to the psychosocial adjustment and total rehabilation of stroke patients.

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