• Title/Summary/Keyword: panel test

Search Result 1,781, Processing Time 0.029 seconds

A Study on the Evaluation of Field Installation Damage and Strength Reduction Factor of Geogrid for Reinforced Retaining Wall (보강토 옹벽용 지오그리드의 현장 내시공성 및 강도 감소계수 평가에 관한 연구)

  • Park, Juhwan;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
    • /
    • v.13 no.7
    • /
    • pp.5-12
    • /
    • 2012
  • Recently the installation of reinforced earth retaining walls in the domestic construction site has increased, surpassing conventional RC walls. These reinforced walls have various types depending on the reinforcing material, installation method and the form of face panel. However, there are difficulties in design and construction management due to the unproved safety of construction method. In case of reinforcing materials, despite the fact that they come in all different sizes and types produced by small businesses or partially imported with cheap price and low quality, no proper standards for designing the walls have been suggested. In order to apply reinforced retaining wall system to broad cases and design the walls effectively considering site conditions, specific design and construction guidelines for efficient construction management are needed. In conclusion, this study verified that reduction factors can be greatly affected by grain sizes and stiffness of backfill materials and granularity range, therefore in case of relatively large construction site, it is required to redesign the reinforced retaining wall by evaluating site installation resistance test, applying respective reduction factors to each backfill material and select the right geogrid depending on the usage of retaining wall so as to enhance the safety of reinforced earth retaining walls with efficiency.

Shear Strength Reduction Ratio of Reinforced Concrete Shear Walls with Openings (개구부를 갖는 철근콘크리트 전단벽의 전단강도 저감률)

  • Bae, Baek-Il;Choi, Yun-Cheul;Choi, Chang-Sik;Choi, Hyun-Ki
    • Journal of the Korea Concrete Institute
    • /
    • v.22 no.4
    • /
    • pp.451-460
    • /
    • 2010
  • There are many types of remodeling, however, engineers and architectures preferred to merge two or more separate units to one very spacious unit. Performing this type of remodeling, in the case of wall dominant apartments, requires partial removal of structural wall causing a concern of structural integrity. However, there are insufficient studies about partial removal, that is, openings. Presently, ACI standard have no clear way to evaluate the effect of opening on the structural wall. AIJ has the provision about strength reduction factor '$\gamma$'. However, this reduction factor cannot exactly evaluate the reduction effect of openings because this factor '$\gamma$' was determined through the elastic analysis. Therefore, in this study, 2 structural wall specimens were tested and many test results from previous studies were collected. Using these data, this study performed statistical analysis about strength of structural wall which have the opening in wall panel. And this study performed parametric study verifying shear strength reducing effect by opening area. In the results of statistical study, previous reduction factor show very conservative results because this equation did not consider other factors, reinforcement ratio and aspect ratio of openings, which was affect the shear strength of shear walls. Therefore we performed parametric study based on the test data and suggest new equation for shear strength reduction factor '$\gamma$'.

Analysis and Evaluation of Degrees of Contribution of Aroma Components in Hongro Apples (홍로사과의 향에 영향을 주는 향 성분 분석과 기여도 평가)

  • Koh, Jin-Tae;Yu, Young-Jae;Kim, Man-Goo
    • Korean Journal of Food Science and Technology
    • /
    • v.41 no.6
    • /
    • pp.603-608
    • /
    • 2009
  • In this study, "Hongro" apples for test samples were selected from a market for aroma analysis. Analysis was done after 1 hr, in a forming headspace while maintaining a temperature of $25^{\circ}C$. First, the complex aroma of the apples was assessed by a Direct Sensory Method. Secondly, the complex aroma was analyzed under individual aroma conditions separated by GC/FID/Olfactometry. Finally, aroma component analysis by GC/MS was performed. Degrees of contribution of aroma components were evaluated by an aroma value calculation considering aroma duration time, frequency, and intensity. The contribution rate (%) of the aroma induction component influencing apple aroma was determined by aroma component analysis and aroma contribution degree. As a result, it was found that the top four components were as follows, by contribution rate (%): acetic acid (23%), 1-hexanol (16%), butyl ethanoate (13%), 4-methoxy-2-methylbutane (9%). These four components constitute the complex aroma tested by the direct sensory method, and was largely recognized by the apple aroma test panel. Consequently, it was found that these components are the key factors in apple aroma. If the mechanism of formation of these components can be found, it could have a significant influence on consumers' acceptance of new varieties of apples.

Effects of Corrugated GFRP Shear Connector Width and Pitch on In-plane Shear Behavior of Insulated Concrete Sandwich Wall Panels (CSWP) (파형 GFRP 전단연결재의 폭 및 너비에 따른 중단열 벽체의 면내전단거동)

  • Jang, Seok-Joon;Oh, Tae-Sik;You, Young-Chan;Kim, Ho-Royng;Yun, Hyun-Do
    • Journal of the Korea Concrete Institute
    • /
    • v.26 no.4
    • /
    • pp.421-428
    • /
    • 2014
  • This paper describes the experimental results of insulated concrete sandwich wall panels (CSWP) with corrugated glass fiber-reinforced polymer (GFRP) shear connectors under in-plane shear loading. Corrugated GFRP shear connectors were used to improve the thermal property of insulated CSWP and to achieve composite action between the interior and exterior concrete wall panels. Test specimens were consist of three concrete panels with two insulation layers between concrete panels and middle concrete panels was loaded in the direction of gravity. To evaluate the effects of insulation types (extruded polystyrene, XPSS and expanded polystyrene, EPS), shear connector pitch (300 and 400 mm) and width (10 and 15 mm) on in-plane shear behavior of insulted CSWP, failure mode and shear flow-average relative slip relationship of specimens were investigated. Test results indicate that the bond stress between concrete panel and insulation is considerable initially. Especially in case of insulated CSWP without shear connector, initial stiffness of CSWP with XPSS is superior to that of CSWP with EPS. The shear connector's contribution to in-plane shear performance of insulated CSWP depends on the type of insulation.

A Study on Supportive Measures to Improve the Job Training and Employment of the Married Immigrant Women by Delphi Survey (여성결혼이민자 취업향상을 위한 지원 방안에 관한 델파이분석)

  • Lee, O-Bok
    • The Journal of the Korea Contents Association
    • /
    • v.14 no.8
    • /
    • pp.197-206
    • /
    • 2014
  • This research intends to explore services, programs or policies for supporting married immigrant women to qualify themselves for being employed from the professional point of view on the assumption that their desire to get a job is high. To achieve this purpose, a delphi survey was conducted with a panel of 13 experts related to multi cultural family support in three sessions from December 20, 2013 to June 5, 2014. To analyze the collected data, descriptive statistics, including frequency, percentage, the mean, and standard deviation, were implemented, and Kendall's W for the internal reliability test on the survey instrument was carried out for statistical processing. The results are as follows : from the first session, services, programs, and policies in the level of married immigrant women themselves, children, parents in law and/or husband, organizations, and government were suggested. The highest item in average is systematization of levelwise Korean teaching program. The next higher items in average are daycare service during job training, parents in law and/or husband's consideration, parenting support services, program development of the organizations, linkage and integration system among the government ministries. As a result of the Kendall's W performed for the internal reliability test of the Delphi research, it has been concluded that the professionals' view on the supportive measures' important contents was statistically identical. According to the results of the Delphi research, systematization of levelwise Korean teaching program most required for the furtherance of the married immigrant women's entering the workforce, followed by provision of the services to draw family support, a grounding teaching of Korean corporate culture, and reconsideration of the policies.

An Empirical Test of the Dynamic Optimality Condition for Exhaustible Resources -An Input Distance Function- (투입물거리함수를 통한 고갈자원의 동태적 최적이용 여부 검증)

  • Lee, Myunghun
    • Environmental and Resource Economics Review
    • /
    • v.15 no.4
    • /
    • pp.673-692
    • /
    • 2006
  • In order to test for the dynamic optimality condition for the use of nonrenewable resource, it is necessary to estimate the shadow value of the resource in situ. In the previous literatures, a time series for in situ price has been derived either as the difference between marginal revenue and marginal cost or by differentiating with respect to the quantity of ore extracted the restricted cost function in which the quantity of ore is quasi-fixed. However, not only inconsistent estimates are likely to be generated due to the nonmalleability of capital, but the estimate of marginal revenue will be affected by market power. Since firms will likely fail to minimize the cost of the reproducible inputs subject to market prices under realistic circumstances where imperfect factor markets, strikes, or government regulations are present, the shadow in situ values obtained by estimating the restricted cost function can be biased. This paper provides a valid methodology for checking the dynamic optimality condition for a nonrenewable resource by using the input distance function. Our methodology has some advantages over previous ones: only data on quantities of inputs and outputs are required; nor is the maintained hypothesis of cost minimization required; adoption of linear programming enables us to circumvent autocorrelated errors problem caused by use of time series or panel data. The dynamic optimality condition for domestic coal mining does not hold for constant discount rates ranging from 2 to 20 percent over the period 1970~1993. The dynamic optimality condition also does not hold for variable rates ranging from fourth to four times the real interest rate.

  • PDF

Relationships among Students' 3rd Year High School Characteristics, College English-mediated Subject Courses, Career Decision Type, and Employment Status (대학에서의 전공영어강의 수강 경험, 고등학교 3학년 때의 경험, 고3 때의 특성, 대학에서의 영어전용 전공강좌 수강경험, 진로결정 유형과 고용상태와의 관계 탐색)

  • Park, Hye-Sook
    • The Journal of the Korea Contents Association
    • /
    • v.14 no.6
    • /
    • pp.442-452
    • /
    • 2014
  • Using the 1st and 7th waves of KEEP(Korea Education and Employment Panel), this study explores the relationships among 212 participants' characteristics during high school, experience of taking English-mediated subject courses(EMSC) during college, career decision types, and employment status. These students' high school experiences and college experiences were used to predict the log-odds of taking and the understanding EMSC. Results of the analysis showed that none of high school characteristics such as career decision, English private education experience, interest in English, and their scholastic aptitude test score in English were associated with taking and understanding EMSC. Among college experience variables, only female students' level of understanding English subject courses was statistically significantly higher than that of male students. There were statistically significant positive associations between the understanding the EMSC and the number of the EMSC taken and also between the understanding of the EMSC and perceived usefulness of the EMSC. There was also a statistically significant relationship between career types (continuing with graduate studies vs. working) and taking EMSC, but the relationship between career types and understanding the EMSC was not statistically significant. In addition, the relationship between the experience of taking EMSC and employment status was not statistically significant.

Quality Characteristics of Garaedduk with Roasted Rice Bran (볶음 미강 첨가량에 따른 가래떡의 품질 특성)

  • Choi, Eun-Hi;Lee, Ji-Hyun
    • Culinary science and hospitality research
    • /
    • v.16 no.5
    • /
    • pp.277-286
    • /
    • 2010
  • This study examines the quality characteristics of garaedduk with roasted rice bran in addition of the control at 10%, 20%, 30% & 40% and to measure the mechanical and sensory quality characteristics in order to show the optimum addition ratio and production condition. The result of adding roasted rice bran with 10% up to 40% in all research groups are as follows; First of all, the moisture content was decreased and the "L" score which represents the brightness of garaedduk showed 68.86 in control which was non supplemented garaedduk. L-value decreased. However, a-value increased significantly and b-value increased except in control group. In the experiment on hadness, it showed 0.69 in control group and it showed 0.94 in garaedduk with 10% of roasted rice bran. Also, there was significant difference in hardness depending on the amount of roasted rice bran and storage period. In the experiment on the sensory evaluation of color and flavor in panel test, all groups showed higher scores than control group. Moreover, there was significant taste difference depending on the amount of roasted rice bran. As a test result, the overall acceptability by sensory evaluation was observed as 30%>10%>20%>40%> in the group added with roasted rice bran.

  • PDF

Static and Fatigue Characteristics of Urethane Foam Cored Sandwich Structures (우레탄 폼 코아 샌드위치 구조물의 정적 및 피로 특성)

  • 김재훈;이영신;박병준;김덕회;김영기
    • Composites Research
    • /
    • v.12 no.6
    • /
    • pp.74-82
    • /
    • 1999
  • The static and fatigue characteristics of polyurethane foam cored sandwich structures are investigated. Three types of the specimens with the glass fabric faces and the polyurethane foam core are used; non-stitched. stitched, and stiffened sandwich specimen. Especially additional structural reinforcements with the twisted polyester and glass fiber for thickness direction are made to stitched sandwich structure panel to minimize the delamination of structure which is stitched the upper and lower faces through the core and the resin is impregnated Into stitched fiber with the characteristics of low viscosity of resin at resin flow temperature and cured together with during the curing process. Bending strength of stitched specimen which is 50 mm $50{\times}50{\;}mm$ pitched is improved by 50 % as com-pared with non-stitched specimen and stiffened specimen is improved 10 times more than non-stitched structure. After fatigue testing of $10^6$cycles by 20% of ultimate load under monotonic load, the bending fatigue strength of non-stitched specimen is decreased by 27% of monotonic bending strength, 39% for stitched structure and 20% for stiffened specimen. To verify the aging effect of polyurethane form core, Ultrasonic C-scanning equipment is used to detect the damage of skin laminate alone after fatigue test. From results of UT C-scan images, there is no defect that can be damaged occurred during fatigue test. It is concluded that the decrease of bending strength for foam cored sandwich specimen is caused by the decrease of stiffness due to the aging of polyurethane foam core during fatigue cycles.

  • PDF

A Study on the Perception of the Importance and Performance of Patient Education of the Clinical Nurses (종합병원 간호사가 인식하는 환자교육 중요도와 수행도의 관계연구)

  • Yoo, Eun-Kyung;Suh, Moon-Ja
    • The Journal of Korean Academic Society of Nursing Education
    • /
    • v.6 no.2
    • /
    • pp.287-302
    • /
    • 2000
  • The purpose of the study are to examine the perception of the importance and performance of patient education of the clinical nurse and find out the interfering factors in practicing patient education. The data were collected from convenient sample of 256 clinical nurses working in the nursing units of adult patients except the psychiatric unit, obstetric unit, dental surgical unit and intensive care unit of one University Hospital in Seoul from September 29 to October 2, 1998. Three measurement tools of self-report- questionnaires developed by researcher used. For the content validity of the questionnaires, two sessions of panel discussion and a pilot test were done and finally factor analysis was done with Varimax method. Analysis of data was done with SAS program using frequency, percentage, means, standard deviation, Pearson's Correlation Coefficients, t-test and ANOVA. The obtained results were as follows : 1. The surveyed nurses perceived the importance of patient education at higher level with mean score of 4.08 among 5 point than their perception of practice( mean score : 3.42). 2. There was positive significant correlation(r=.29, p=0.0001)between nurses' perception of the importance of patient education and it's practice 3. Among the teaching contents for patients, 'information of diagnostic procedure and operation' and 'orientation of hospitalization' were perceived most important. And 'preparation for discharge' and 'understanding of disease and health promotion' were perceived least important 4. Among the teaching contents for patients, 'orientation of hospitalization' and 'information of diagnostic procedure and operation' were perceived highly performable. And 'understanding of disease and health promotion' and 'preparation for discharge' were perceived least performable. 5. Three types of interfering factors were identified as patient-factor, situational factor, nurse-factor. The mean degree of impediment with the interfering factors was at average level(3.09 among 5). The patient and situational factors of impediments were more interfering than nurse- factor for teaching patients. 6. In older age(p<.05), married state (p<.05), higher educational status (p<.01), higher clinical experience (p<.01) and higher position(p<.01), the score of perceived importance of patients education was more high. 7. In older age(p<.01), higher clinical experience(p<.001) and surgical unit (p<.01), the score of perceived performance of patients education was more high. In conclusion, in order to activate patient education practice in the clinical setting, the continuing education for patients education should be more emphasized and the effective teaching methods and materials should be developed to help patient teaching. And an organizational support such as budgeting for patient education and reimbursement system should be administrated.

  • PDF