• Title/Summary/Keyword: Alternative test method

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Alternative Method of Determining Resilient Modulus of Subbase Materials Using Free-Free Resonant Column Test (현장공진주시험을 이용한 보조기층 재료의 대체 $M_R$ 시험법)

  • Kweon, Gi-Cheol;Kim, Dong-Su
    • International Journal of Highway Engineering
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    • v.2 no.2
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    • pp.149-161
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    • 2000
  • The stiffness of the subbase materials is represented by the resilient modulus, $M_R$, which are very important properties in the mechanistic design of flexible pavement system. However, the cyclic $M_R$ testing method is too complex, expensive, and time consuming to be applicable on a production basis. In this study, the alternative $M_R$ testing technique for subbase materials was developed using a free-free resonant column (FF-RC) test considering deformational characteristics of subbase materials. To estimate the deformational characteristics of subbase materials, effects of strain amplitude and mean effective stress on modulus of subbase materials were investigated. The $M_R$ values determined by alternative testing procedures matched well with those determined by standard $M_R$ test, showing the capability of the proposed methods being used in determining $M_R$ values.

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Bearing Capacity Evaluation of the Drilled Shaft Using Small Scale Model Test (축소모형말뚝을 이용한 현장타설말뚝의 지지력 평가)

  • 조천환;김홍묵;김웅규
    • Journal of the Korean Geotechnical Society
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    • v.20 no.5
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    • pp.117-126
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    • 2004
  • Recently, the top & down method with drilled shafts as a foundation of high rise building is often adopted for the purpose of construction period reduction and construction cost effectiveness. It is common to omit the loading test as a quality assurance on account of the high capacity of drilled shafts for the top & down method. It seems that the capacity of drilled shaft in recent top & down method is beyond that of conventional loading test method. However, the quality assurance for the drilled shaft as foundation of high rise building becomes much more important since the drilled shaft should bear much higher working load. A small scale test pile can be an alternative as a quality assurance for the drilled shaft with hish capacities. Through a case study, this paper gives an idea for solving the limitation of the conventional loading test method for the quality assurance of drilled shaft with high capacities. In particular, this paper analyzed the scale effect for a small drilled shaft installed into bedrock, which could be used for an alternative.

Heat Transfer Coefficients of Concentric Annuli for Testing Heat Transfer Characteristics of Alternative Refrigerants in Tubes (대체냉매 관내 열전달특성 시험을 위한 동심이중원관의 환상유로의 열전달계수)

  • KIM, MAN-HOE
    • Transactions of the Korean hydrogen and new energy society
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    • v.32 no.1
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    • pp.63-67
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    • 2021
  • Accurate measurements of the heat transfer coefficients of concentric annular space for the test section is important to measure the tube-side heat transfer coefficients of working fluids. This paper presents the annular side heat transfer coefficients of concentric annuli with variation of tube diameter ratios using Wilson plot method. The test facility has a straight, horizontal test section with an active length of 3.0 m. Inner/outer diameters of test tubes are 7.0/7.5 and 8.0/8.56 mm, respectively. An outer diameter of annulus side is 16.0 mm. The test results show that convective heat transfer coefficients in annuli increase with annular diameter ratio. The correlations for convective heat transfer coefficients in annuli are also developed.

Application of Sand Mat Substitutel using Steel Slag (제강슬래그를 이용한 샌드매트 대체재료의 적용성 연구)

  • Park, Jong-Beom;Lee, Byung-Chan;Ju, Jae-Woo;Na, Hyun-Ho
    • Journal of the Korean Geosynthetics Society
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    • v.11 no.1
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    • pp.57-63
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    • 2012
  • Steel slag has the nature to hydrate and expand when in contact with non-reacting CaO and water, and thus can be used only in limited scope for landfill disposal as well as for recycling as civil construction aggregates. In order to use such steel slags more efficiently, the applicability of steel slag as sand mat alternative material was reviewed. In general, sand mat is used in soft ground surface reinforcement method and horizontal drain method, and is installed simultaneously with soft ground vertical drain method. Therefore in this study steel slag designing method and application standard etc were examined to recycle steel slag as sand mat alternative material, and laboratory soil test and model test were done. Test results indicated that the designing method and application standard meet various environment and quality standards, meaning that steel slag can be utilized as sand mat alternative material, and analysis of slag mat bearing capacity also indicated that use of steel slag produces double or more bearing capacity compared with existing sand mat.

Cytokine Release from Organotypic Human Oral Tissue Following Exposure to Oral Care Product Chemicals

  • Yang, Song-Yi;Piao, Yin-Zhu;Kim, Kwang-Mahn;Kwon, Jae-Sung
    • Journal of Korean Dental Science
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    • v.14 no.2
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    • pp.51-60
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    • 2021
  • Purpose: Measuring viability of a three-dimensional in vitro organotypic human oral tissue model has been suggested as an alternative test method to the oral mucosa irritation test of oral care products. The aim of this study was to investigate the production of two different cytokines using organotypic human oral tissue model following exposure to chemicals that are commonly used in oral care products. Materials and Methods: The organotypic human oral tissues were exposed to ethanol, sodium lauryl sulphate or hydrogen peroxide for 90 minutes. Following exposure, interleukin (IL)-1α and IL-8 productions were assessed and correlated with cell viability testing as well as histology of the organotypic human oral tissues. Result: High levels of IL-8 were released from organotypic human oral tissues in all of the test and control groups without any significant differences between them. In contrast, differences were found in IL-1α release between the test and control groups. Additionally, the trend of IL-1α release corresponded to the phenotypes observed in histological analysis while different trend existed between IL-1α release and cell viability. Conclusion: The study concluded the non-specific release of IL-8 for the assessment of oral care product chemicals' toxicity, while potential of measuring IL-1α cytokine level as the possible alternative test method.

The effect of teaching cardiopulmonary resuscitation using a song (노래를 이용한 심폐소생술의 교육 효과)

  • Lee, Won-Joo;Lee, Chang-Seop
    • The Korean Journal of Emergency Medical Services
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    • v.20 no.1
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    • pp.31-39
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    • 2016
  • Purpose: This study proposed an improved method of teaching cardiopulmonary resuscitation (CPR). Methods: A teaching method for CPR using a song was evaluated. To validate the effect of this teaching method, we performed a comparative reference test against a traditional CPR lecture-oriented education method. A total of 202 study participants were enrolled in this project. Half were taught by the traditional CPR education method, and the other half were taught by the alternative educational method using a song. Results: The results for those educated by the traditional lecture-oriented method showed scores of 4.84 / 6.00 (Mean of knowledge) and 70.22 / 100 (Mean of practice ability for CPR). The results for those educated by the alternative method showed scores of 5.26 / 6.00 (Mean of knowledge) and 74.13 / 100 (Mean of practice ability for CPR). The alternative educational method utilizing a song improved the results on written and practical examinations. This improvement could be attributed to the effect of music on memory circuits in the brain. Conclusion: We believe that the results of this study will help to improve the success rates of CPR.

A Study on Use of Alternative Therapy in Chronic Ill Patients (만성 질환자의 대체요법 이용 실태 조사연구)

  • Lee You-Chin;Park Hyoung-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.6 no.1
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    • pp.96-113
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    • 1999
  • This retrospective descriptive study was conducted to survey the use of alternative therapy by chronicly ill patients. The subject of this study were 205 chronicly ill patients at Pusan National University Hospital. The data for this study were patient record. The data were gathered from August, 1 to September, 30 1998 and analyzed through SPSSWIN program for frequency, percentile and $x^2-test$. The important results of this study are as followings. Of population-sociological characteristics on studied objects, sexual distribution showed a similar percentage male 47.8% and the female 52.2%. Age distribution showed that the 60-69 year old group made up 31.5%, and was the highest. Of religion Buddism was the most frequest. The diagnosis distribution showed cancer at 28.8% and coronary artery disease at 16.1%. According to the results of the study, 51.2% of subjects had used alternative therapy. The most common type of alternative therapy was dietary and nutritional therapy, 40.2%, the place of use, home, 44.0%, duration, less than 3 months, 51.5%. The most common motive was a recommendation by friends or family. The degree of satisfaction after the use of alternative therapy was high for 21.0%, and slight for 53.3%. The reaction after the use of alternative therapy was increasing power for patients with coronary artery disease and cancer, sugar control for those with DM, and pain control for those with chronic arthrits. The study showed that for chronicly ill patients, age, religion, diagnosis name have an important effect on the use of alternative therapy. In conclusion, chronicly ill patients showed high-use of alternative therapy but they did not used alternative therapy as a healing method. Therefore we must provide an education program nurses and physicians. And we must provide more information or healing method's and support chronicly ill patients.

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A Study on the Alternative Method for Weathering Test of Military Coated Fabrics (군용 도포직물의 내후성시험 대체에 대한 연구)

  • Son, Chanyoung
    • Journal of Korean Society for Quality Management
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    • v.44 no.3
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    • pp.509-526
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    • 2016
  • Purpose: We would like to find the alternative method for the weathering test on rubber coated fabrics and adhesive-coated fabrics for the military products, KS M 0706 (Sunshine carbon arc) to KS M ISO 4892-2 (Xenon arc). Methods: We measured the tensile strength of adhesive-coated fabrics and adhesive products treated with sunshine carbon arc and xenon arc during 100, 150 and 200 hours, respectively. All of the results were treated with statistical test, ANOVA method. We also validate the surface modifications caused by treatment method and time by using FT-IR ATR and, SEM. Results: In case of the thick adhesive-coated fabrics (app. 1 mm), there was no distinctive difference on tensile strength by treatment method and time. In case of the thin mask hood (app. 0.22 mm) and TENT (app. 0.5 mm), there was distinctive difference on tensile strength. Especially, carbon arc showed a huge lowering properties. We could validate the curing from light and moisture, and the functional group change from cross-linking and oxidation using FT-IR ATR. In case of IBS, there was a surface cracks on SEM images. In case of mask hood, there was no distinctive differences, except for a particle falling from decreased affinity between rubber and particles caused by carbon arc. Conclusion: We concluded that there was no problems for changing xenon arc weathering test with same treatment time on IBS, KM7, K21 and adhesive products. In case of TENT and mask hood, there was a difference in tensile strength in accordance with the change of the treated time and method.

Parametric Study on Test Method for Pull-off Strength of FRP Composite Material used in Strengthening RC Members (FRP 복합체의 콘크리트에 대한 접착강도 시험방법 변수 연구)

  • Choi, Ki-Sun;You, Young-Chan;Lee, Han-Seung;Kim, Keung-Hwan
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05a
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    • pp.222-225
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    • 2006
  • Pull-off test is widely used to evaluate bond performance between concrete and FRP composite. However, reliability of experiment result declines due to many difference between test methods of each national standards. This study analyzed problems of various existing test methods for pull-off test and suggested standardized test method. In addition, since tensile strength of concrete is smaller than bond strength of epoxy resin, maximum bond strength of epoxy resin shall be limited within tensile strength of concrete. Alternative testing method, therefore, which decrease FRP adhesion areas than concrete adhesion areas is suggested to widen test range of bond strength in pull-off test. In the experimental results, bond performance can be estimated up to two times of tensile strength of concrete by reducing FRP adhesion areas by 1/3.

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Development and Application of an Online Alternative Therapy and Health Promotion Class (대체요법과 건강증진 가상강좌 개발 및 적용)

  • Park, Jeong-Sook;Kwon, Young-Sook;Lee, Hye-Ran
    • Journal of Korean Academy of Nursing
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    • v.36 no.2
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    • pp.286-298
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    • 2006
  • Purpose: This study was to develop an online 'alternative therapy and health promotion' class for university students and to evaluate its changes. Method: The online class was developed based on the Instructional Systems Development(ISD) model and model of Web-Based Instruction(WBI) developmental process. This was a quasi-experimental, one group pretest-posttest design. The subjects of this study were 130 students in 3 universities, and they were provided the cyber class for 16 weeks. Data was analyzed by descriptive and plural answer statistics, and paired t-test. Results: The cyber class was developed in five steps : analysis, design, data collection and reconstruction, programing and publishing, and evaluation. The results of program evaluation were positive, which included learning 3.47. system 3.57, and learning satisfaction 3.64 on the scale of 5. The posttest scores of cognition and reliability of alternative therapy were higher than pretest scores. The posttest score of health promoting lifestyle(t=-5.051, p=.000) and perceived health status(t=2.979, p=.003) were significantly higher than those of the pretest. Conclusion: These results suggest that the cyber class is a positive method in increasing a cognition, reliability of alternative therapy, and is effective to improve a health promotion lifestyle and perceived health status for the university students.