• 제목/요약/키워드: test results

검색결과 71,196건 처리시간 0.074초

하이브리드 복합재료의 전단 물성치 측정에 관한 연구 (A study of the shear properties for hybrid composites)

  • 백운철;조맹효;황재석
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2002년도 추계학술발표대회 논문집
    • /
    • pp.96-99
    • /
    • 2002
  • In order to determine the in-plane shear properties of unidirectional carbon fiber reinforced aluminum laminate composites, a new Iosipescu shear test fixture was developed, by using a fixture undergoing tensile force for the specimen edge to be subjected to compressive loads assumption, under plane stress. Also, to compare the results, Iosipescu shear test method by the modified Wyoming fixture and the off-axis tensile test were performed to determine the shear properties. Off-axis tension test was performed by using new oblique-shaped tabs proposed by Sun and Chung. [5] The oblique tabs reduced remarkably end-constraint effects of off-axis specimens with a aspect ratio of about eight. It is observed through the experimental results show that there is no significant difference between off-axis test results and those of Iosipescu shear test.

  • PDF

터보펌프+가스발생기 연계시험 연구 (Study on Turbopump and Gas Generator Coupled Tests)

  • 김승한;남창호;설우석
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2007년도 제29회 추계학술대회논문집
    • /
    • pp.155-158
    • /
    • 2007
  • 액체로켓엔진 개발 시험의 중간 단계로서 연소기를 제외한 터보펌프 등의 엔진 주요 구성품을 이용한 터보펌프+가스발생기 연계시험이 수행 중에 있다. 터보펌프+가스발생기 연계시험의 시험기 및 시험설비 구성을 기술하였다. 연계시험 수행을 위한 시험설비 시스템 검증 시험 결과를 제시하였다. 시험설비에 대한 예비시험 결과를 토대로 시험설비 추진제 공급시스템의 검증이 수행되었다.

  • PDF

직경 2m급 축소로터 시험장치 개조 및 보완 (Modification of Dia. 2m-Small-scaled Rotor Test Facility)

  • 송근웅;이재하;김승호
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2012년도 추계학술대회 논문집
    • /
    • pp.190-195
    • /
    • 2012
  • Small-scaled Rotor Test facility(GSRTS, General Small-scaled Rotor Test Facility) in KARI could not use the test because facility aging and parts discontinued. Also in order to perform a joint international research, GSRTS modifications should be needed. So requirements of GSRTS modifications were established and according to the requirements, GSRTS modifications were conducted. Facility operation test, 6-component fixed balance calibration, Small-scaled OLS rotor performance test were performed to verify the results of GSRTS modifications. Reasonable results were obtained in comparison to calculation results. Then GSRTS ready was completed to conduct international collaborative research and wind tunnel test.

  • PDF

연약지반에 대한 기계식 및 전자식 콘관입시험 비교 연구 (Comparative study of Dutchcone and piezocone test on soft ground)

  • 장병욱;김재현;김동범;윤상묵;원정윤
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2002년도 가을 학술발표회 논문집
    • /
    • pp.237-244
    • /
    • 2002
  • A comparative study of 134 mechanical (Dutch cone) and 9. electronic cone (Piezocone) penetration data from the southern part of Korea has been performed. In general, Dutch cone results may be different from piezocone results due to the difference in structure of the cones. Cone penetrometer test data were analyzed and plotted in soil classification chart proposed by Robertson et. al.(1986,1990) Cone factors of Dutch cone and piezocone test have empirically been determined using laboratory and field vane test results. Using this cone factors, it was shown that there was good correlation between shear strength estimated using cone resistance and that of laboratory test and field vane tests. It was found that there was a good correlation between cone resistance from Dutch cone and that from piezocone. Dutch cone test provides a useful means for stratigraphic profiling in large project and has some advantage over piezocone in particular situations, such as very soft clay ground and dredged area.

  • PDF

습도를 고려한 절연유 시험 결과의 보정 방안 연구 (Correction Measures That Take Humidity into Account in Insulating Oil Test Measurement Results)

  • 김완수;노재필;강석구
    • 한국전기전자재료학회논문지
    • /
    • 제37권5호
    • /
    • pp.541-546
    • /
    • 2024
  • Climate conditions, especially transport and storage, are a very important factor in the process of sampling and testing insulation oil in the field. The samples of insulating oil exposed to the atmosphere affect the dielectric strength, total acid number and moisture test value by oxygen and high humidity environment and may also affect the results according to the criteria specified in each test. Therefore, reliable test values for insulating oil testing require consideration of the atmospheric environment of the test site, including oxygen and humidity. In this paper, each test was conducted on insulating oil exposed to various time and humidity environments, and the effect of the atmospheric environment on the test results was analyzed by comparing and analyzing with the first insulating oil.

잠재력훈련 집단상담이 성인 간질환자의 치욕감에 미치는 효과 (The Effect of Human Potential Seminars on the Perceived Stigma of Adults with Epilepsy)

  • 김은자
    • 대한간호학회지
    • /
    • 제28권4호
    • /
    • pp.1003-1012
    • /
    • 1998
  • The purpose of this research was to identify the effect of human potential seminars on the perceived stigma of adults with epilepsy. The research employed a quasi experimental design and unequivalent control group pre-post design. The test was conducted on 15 adults with epilepsy attending one psychiartric out-patient clinic in Masan City, Korea. The stigma questionnaire was used as a pre-test to these patients. HPS was done ten times for five weeks from May 6, to July 26, 1996. The stigma questionnaire was again given, but this time as a post test. The control group of 14 adults with epilepsy were receiving medication at the same clinic. The human potential seminars were structured by McHolland(1972) and translated by Lee, Hae Seung(1990). The stigma research tool was modified and revised to be appropriate to Korean culture. It consisted of 15 sentences. The internal consistency was 0.92 with Cronbach's α. Research results are as follows. 1) To determine the homogenity of the experimental and control groups, the pre-stigma results were used and democratic-sociologic characteristics, job characteristics and disease related variables were compared. There was no significant difference between the two groups. 2) To identify the relationship between stigma and patient characteristics a pre-test was done. The study used both Mann-Whitney U-test and ANOVA test for statistical analysis. The variables related to stigma were the reason of unemployment and age at onset of epilepsy. 3) The test results of the effect of the human potential seminars on stigma in the patients with epilepsy, showed that stigma in the experimental group was lower than in the control group. The statistical method used to determine the difference between pre and post stigma results was the Wilcoxon signed rank test. The test results were statistically significant at the one percent level. 4) As a follow-up evaluation ten more patients(66.7% of the total) were additionally tested. In order to investigate if the stigmas were different between the pre, post and follow-up, Repeated measure ANOVA was used. The test results showed that the stigma scores were statistically different between the three groups at the one percent level(F=10.06, d.f.=2, p=0.00).

  • PDF

Hybrid mesh 및 sliding mesh를 이용한 선박 저항추진 성능 시험 (SHIP RESISTANCE AND PROPULSION PERFORMANCE TEST USING HYBRID MESH AND SLIDING MESH)

  • 박범진;이신형
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2009년 추계학술대회논문집
    • /
    • pp.77-83
    • /
    • 2009
  • In this study, we conducted resistance and propulsion performance test of ship composed of the Resistance Test, Propeller Open Water Test and Self Propulsion Test using the CFD(Computational Fluid Dynamics). We used commercial RANS(Reynolds Averaged Navier Stokes equation) solver, as a calculating tool. The unstructured grids were used in a bow and stern of ship, having complex shape, for a convenience of generating grids, and the structured grids were adopted in a central hull and rest of hull having a relatively simple shape which is called hybrid grid method. In addition, The sliding mesh method was adopted to rotate a propeller directly in the Propeller Open Water and Self Propulsion Test. The Resistance Test and Self Propulsion Test were calculated using Volume of Fluid (VOF) model and considering a free surface. And all The three cases were applied realizable k-epsilon model as the turbulence model. The results of calculations were verified for the suitability of calculations by comparing MOERI's EFD results.

  • PDF

수치수조에서의 평면운동시험 시뮬레이션 (HPMM Simulation in Numerical Towing Tank)

  • 정두진;신기석;박선호;허재경;유병석
    • 대한조선학회 특별논문집
    • /
    • 대한조선학회 2007년도 특별논문집
    • /
    • pp.74-78
    • /
    • 2007
  • In this paper, the HPMM(Horizontal Planar Motion Mechanism) test is simulated in a numerical towing tank by using a commercial CFD(Computational Fluid Dynamics) code, FLUENT. The results of calculation are compared with those of static drift test or rotating arm test calculated by CFD to verify the results simulated by CFD. Through comparing pure sway test of HPMM test with static drift test and pure yaw test of HPMM with rotating arm test, it is found that HPMM test can be simulated in the numerical towing tank.

  • PDF

전해부식시험을 이용한 니켈-크롬도금강판 및 아연도금강판의 내식성 비교평가시험 (Evaluations of corrosion resistance of Ni-Cr plated and Zn-plated Fe Substrates Using an Electrolytic Corrosion Test)

  • 이재봉;김경욱;박민우;송태준;이채승;이의종;김상열
    • Corrosion Science and Technology
    • /
    • 제12권1호
    • /
    • pp.56-64
    • /
    • 2013
  • An Eectrolytic Corrosion(EC) test method was evaluated by the comparison with Copper Accelerated Acetic Salt Spray(CASS) and Neutral Salt Spray(SS) tests. Those methods were applied in order to evaluate corrosion resistance of Ni-Cr plated and Zn-plated Fe substrates. The correlations between results obtained by different test methods were investigated. Results showed that the electrochemical method such as the EC test method was superior to the conventional methods such as CASS and SS, in terms of the quantitative accuracy and the test-time span. Furthermore, the EC test method provided the useful means to estimate the initiation of corrosion of each layer by monitoring the rest potentials of the coated layers such as Ni, Cr, and Zn on Fe substrate. With regard to test time spans, the EC test provided the 78 times and 182 times faster results than the CASS test in cases of $Fe+5{\mu}m$ $Ni+0.5{\mu}m$ Cr and $Fe+20{\mu}m$ $Ni+0.5{\mu}m$ Cr respectively, while the EC test was 85 times faster results than the Salt Spray test in the case of $Fe+20g/m^2$ Zn. Therefore, the EC test can be the better method to evaluate the resistance to corrosion of coated layers than the conventional methods such as the SS test and the CASS.

VALIDATION AND UTILIZATION OF THE SKINTEXTM SYSTEM

  • Gordon, V.C.;Realica, B.;Tolstrup, K.;Puls, B.
    • 대한화장품학회지
    • /
    • 제17권1호
    • /
    • pp.64-80
    • /
    • 1991
  • The SKINTEX Method is based on a two-compartment physico-chemical model which includes a Biomembrane Barrier in compartment one and an organized macromolecular matrix in compartment two. Test samples absorb onto or permeate through the keratin/collagen Biomembrane Barrier and then can interact with the organized macromolecular matrix. Changes in the integrity of the barrier release a dye indicator: Changes in the matrix can alter its transparency. The sum of these two responses is read spectrophotometrically at 470nm. An early investigation of 950 chemicals and formulations in the SKINTEX System produced results which were 89% concordance to in vivo Draize dermal irritation results obtained with 24-hour occluded application of test samples with-out abrasion and standard scoring. Alkaline materials were analyzed in a specialized SKINTEX AMA Protocol. In this early study, the model did not distinguish nonirritant test materials and formulation with PDII(Primary Dermal Irritation Index)in the range from 0 to 1.2, A High Sensitivity Assay Protocol(HSA)was developed to amplify the changes in both compartments of this model and provide more accurate calibration of these changes. A study of 60 low irritation test samples including cosmetics, household products, chemicals and petro-chemicals distinguished nonirritants with PDII $\leq$ 0.7 for 26 of 30 nonirritants. A second protocol was developed to evaluate the SKINTEX model predictability with respect to human irritation. The Human Response Assay (HRA )has been optimized based on differences in penetration and irritation responses in humans and rabbits. An additional 32 test materials with different mechanisms and degrees of dermal toxicity were evaluated by the HRA. These in vitro results were 86% concordant to human patch test results. In order to further evaluate this model, a Standard Chemical Labelling (SCL) Protocol was developed to optimize this system to predict Draize dermal irritation results after a 4-hour application of the test material. In a study of 52 chemicals including acids, bases, solvents, salts, surfactants and preservatives, the SCL results demonstrated 85% concordance to Draize results for a 4-hour application of test samples on non-abraded rabbit skin. The SKINTEX System, including three specialized protocols, provided results which demonstrated good correlation to the endpoint of dermal irritation in man and rabbits at different application times.

  • PDF