• Title/Summary/Keyword: standardized experimental method

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Comparision of Test Methods for Estimating Chloride Ion Diffusion Coefficient in Concrete (콘크리트중의 염소이온 확산계수 추정 실험법의 비교)

  • 문한영;김홍삼;문재흠;한아름
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.787-790
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    • 1999
  • To estimate durability of reinforced concrete structures located in or nearby seawater, many different kinds of accelerated tests for evaluation of chloride ion permeation in concrete were proposed. At present the only standardized test is the ASTM C 1202(RCP test). This test method is used to estimate the concrete's resistivity of the chloride penetration in concrete by using the total charges passed and sometimes used to calculate the chloride diffusion coefficients. However, this test may lead to an erroneous chloride diffusion coefficient. So this test method was compared with the modified Dhir's test and the traditional concentration diffusion test. Experimental results showed that the diffusion coefficients determined the RCP test and the PD Index gave wrongous values, but the diffusion coefficient acquired by considering a migration term was nearly the same to the CD Test.

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Rotation Angle Estimation of Multichannel Images (다채널 이미지의 회전각 추정)

  • Lee Bong-Kyu;Yang Yo-Han
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.51 no.6
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    • pp.267-271
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    • 2002
  • The Hotelling transform is based on statistical properties of an image. The principal uses of this transform are in data compression. The basic concept of the Hotelling transform is that the choice of basis vectors pointing the direction of maximum variance of the data. This property can be used for rotation normalization. Many objects of interest in pattern recognition applications can be easily standardized by performing a rotation normalization that aligns the coordinate axes with the axes of maximum variance of the pixels in the object. However, this transform can not be used to rotation normalization of color images directly. In this paper, we propose a new method for rotation normalization of color images based on the Hotelling transform. The Hotelling transform is performed to calculate basis vectors of each channel. Then the summation of vectors of all channels are processed. Rotation normalization is performed using the result of summation of vectors. Experimental results showed the proposed method can be used for rotation normalization of color images effectively.

The Status of Laboratory Animal Production and Visions in the 21st Century - Review -

  • Gartner, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.7
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    • pp.1142-1151
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    • 1999
  • Today, laboratory animal production has decreased world-wide to half the number estimated in 1970 of more than 100 Mio. This is due to the cell-biological assays which replaced animal experimentation as a first allround method to solve biomedical problems. Animal experimentation remains the most significant experimental method for the study of higher organized physiological systems and their multifactorial connections. This requires maximal uniformity of all quantitative traits among the animals used for such studies (mainly mice and rats) and stability of these traits for reproducing such studies at any time world-wide. The success of the developed methods for the standardization of laboratory animals was analyzed and were found only partly be acceptable. Getting a higher degree of uniformity among standardized inbred animals is blocked by "intangible variance". This is caused by influences of ooplasm, shown by experimental twin and clone studies. Manipulation of this component of variance is essential in the future. - Genetic drifts impair the necessary stability of biological traits. There are a few disadvantages associated with the cryopreservation of embryos and other methods are required. - Dogs and cats were replaced by pigs as laboratory animals. A new line of animal production will evolve over the next 25 years with similarities to the present laboratory animal production, because in future pigs were used as donors for xenotransplants for men.

A Study on the Electronically Controlled Cooling system for Bimodal Tram (바이 모달 트램의 전기 제어 장치용 냉각장치에 관한 연구)

  • Kim, Chang-Uk;Kim, Hea-Soo;Song, Jung-Il
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.4
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    • pp.91-98
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    • 2014
  • In this study, the first and second electronically controlled cooling systems for a bimodal tram were developed. The performance characteristics of the cooling systems were assessed experimentally with actual and identical conditions, and a simulation was run using ANSYS Fluent. The results of the experimental and FEA method were standardized. In order to confirm the reliability of the experimental method, the experiment was carried out by a testing institution. The low-volume flow-rate condition was found to be better, but the cooling system performed in a minimal condition. Therefore, it is important to find the optimum performance levels. The cooling system equipment was revised to determine the optimized design parameters, after which the cooling performance levels increased at the radiation area. Specifically, with a greater fan diameter. Through this study, the newly developed cooling system will be reevaluated after being mounted on an actual bimodal tram. This will lead to a completely domestically produced bi-modal tram cooling system.

Relationship among Chemical Properties of Soils with Different Texture Taken from Plastic Film House of Chungbuk Area (충북지역 시설재배지 토성별 토양화학성의 상호관계)

  • Kim, Jai-Joung;Kang, Seong-Soo;Kim, Ki-In;Hong, Soon-Dal
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.3
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    • pp.144-150
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    • 2006
  • Chemical characteristics and their interrelationships of 156 soils included by 74 sandy loam and 82 loam soils collected from plastic film house in Chungbuk area were investigated from 1998 to 2001. Seventeen chemical properties including pH, organic matter (OM), electrical conductivity (EC), inorganic nitrogen, available phosphorus, exchangeable cations, CEC, etc., were analyzed by correlation, standardized partial regression coefficient, and principal factor analysis. Standardized partial regression coefficients of chemical properties were estimated to determine the degree of contribution of EC and OM contents in soils. Principal factor analysis was applied to classify the studied chemical properties into different groups having similar chemical properties. The pH of experimental soils ranged from 4.24 to 7.14 and 4.95 to 7.35 for loam and sandy loam soils, respectively. The EC of soils varied from 0.93 to $15.65dS\;m^{-1}$ for loam and $0.91{\sim}22.30dS\;m^{-1}$ for sandy loam soils, respectively with significant differences among them. The EC measured by 1:5 $H_2O$ dilution method and saturation method were significantly related with 8.163 and 8.599 as the slopes of regression equation for loam and sandy loam soils, respectively. These slopes more than 8.0 in this regression equation was higher than the slope of 5.0 that is estimated from dilution coefficient suggesting that EC measured by 1:5 dilution method might be erratic. The standardized partial regression coefficient of different chemical properties for the estimation of EC was in the order of $NO_3{^-}$ > $Cl^-$ > OM > exchangeable Mg for loam soils and $NO_3{^-}$ > exchangeable Mg > $Cl^-$ for sandy loam soils. Contribution order of the chemical properties based on standardized partial regression coefficient differed 1:5 dilution method and saturation method, indicating that different chemical compounds might be present in the extract solutions of these two methods. Consequently the measurement of EC by saturation method was thought be still better for estimation of chemical property because accuracy of EC measurement by 1:5 dilution method can't be improved by any specific coefficient for adjustment of EC. Regardless of differences in soil textures and extraction methods, correlation coefficients between EC and the other chemical properties were routinely in the order of $NO_3{^-}$ > $Cl^-$ > degree of base saturation > exchangeable Mg > exchangeable Ca > $SO{_4}^{2-}$. The principal factor analysis revealed four factor groups of the chemical properties studied. The groups for sandy loam were as follows; ; 1. salt components, 2. soil reaction components, 3. fixed and adsorption components, 4. CEC components. The groupings of loam soils were similar to sandy loam except that exchangeable Na substituted the CEC of sandy loam.

Bacteria reduction ratio by cleansing methods of latex gloves (라텍스 장갑의 세척 방법에 따른 세균 감소율 측정)

  • Yang, Song-Yi;Oh, Jeong-Min;Song, Da-Hye;Song, Bo-Ram;Kang, Myung-Jin;Lee, Myung-Sun;Son, Ga-Yeon;Oh, Sang-Hwan
    • Journal of Korean society of Dental Hygiene
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    • v.14 no.4
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    • pp.593-599
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    • 2014
  • Objectives : Latex gloves hygiene is the most effective method to prevent infection of microorganisms and to reduce the incidence of cross infections. The aim of this study was to compare the bacteria reduction ratio of cleansing with water, liquid soap and alcohol gauze. Methods : The left side glove was the control group and the right side was the experimental group. The experimental group washed hand with water, soap, and alcohol gauze. The hand plate was inoculated by the hand and inoculated for 24 hours in $35^{\circ}C$. Results : Washing with water showed that CFU of control group was 1116.9 and that of experimental group was 302.8. Hand washing by water reduced 74.3% of bacteria. Liquid soap revealed that CFU of control group was 619.9 and that of experimental group was 8.3. Hand washing by liquid soap reduced 97.5% of bacteria. Alcohol gauze included 875.2 CFU in control group and 5.8 CFU in experimental group. Washing by alcohol gauze reduced 99.5% of bacteria. Conclusions : Based on the results, the most effective latex gloves cleansing method was recommended as the standardized hand washing with the liquid hand soap and alcohol gauze. The results can be used to improve training strategies for enhancing glove hygiene practice in dental clinic.

Experimental Evaluation on JGS Frost Susceptibility Testing Method (일본 동상민감성 판정 기준에 관한 고찰)

  • Jangguen Lee;Hyunwoo Jin;Zheng Gong
    • Journal of the Korean GEO-environmental Society
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    • v.25 no.7
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    • pp.21-27
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    • 2024
  • Frost heave, a significant engineering aspect of frozen ground, leads to various damages in Korea during the winter. Both the United States and Japan, encompassing regions with frozen ground, have actively researched frost heave and possess standardized experimental methods. Particularly, the Japanese Geotechnical Society (JGS) has introduced a frost heave standard testing method, offering the advantage of relatively simple specimen preparation and experimental procedures. However, issues persist regarding the ambiguous engineering interpretation of frost heave test results and the lack of clear criteria for frost heave susceptibility assessment. This paper presents laboratory testing results following the JGS testing method on sand and silt mixtures using a triaxial temperature-controllable cell, and thoroughly analyzes the frost heave rate calculation process. Furthermore, it evaluates the applicability of frost heave susceptibility criteria proposed in the United States to frost heave rates based on the JGS testing method.

Analysis of Gerontological Nursing Researches in Korea from 1997 to 2003 (국내 노인간호연구 분석 (1997년부터-2003년까지))

  • Yang, Kyung-Mi;Park, Chai-Soon;Kim, Soon-Lae
    • Research in Community and Public Health Nursing
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    • v.15 no.3
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    • pp.419-437
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    • 2004
  • Purpose: This study aims to analyze the trends of the gerontological nursing researches in Korea and suggest the direction for research in this nation. Method: A total of 241 dissertations and other published articles in Korea from 1997 to 2003 were analyzed in this study focusing on the design of the research, key words, measurement tools for basic concepts, and the intervention outcomes in the case of the experimental research. Result: Of those analyzed researches. it was found that 80.9% accounted for the published articles and 19.1% dissertations. There were no clear criteria for the classification of the old men. The most popular research design was an exploratory/descriptive study (54.4%). The major concepts were about 'physical and mental health'. Most of the measurement tools used were developed by foreigners. which were translated into Korean. Among 56 experimental studies, nursing intervention programs in 22 studies were based on physical exercise programs. Conclusion: It is necessary to analyze the trend of gerontological health research in comparison with multidisciplinary researches for elderly people. In addition, the experimental researches for both development and verification of nursing intervention programs are needed. Also, accumulation of research outcomes and development of a standardized instrument for the measurement of Korean elderly people are required.

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An Experimental Study for Suggestion of Simple Method of Determining the Maximum Relative Density (최대상대밀도 산정 간편법 제안을 위한 실험연구)

  • Lee, Jong-Jin;Kim, Myong-Mo;Lee, Seung-Hyun;Kim, Byoung-Il
    • Journal of the Korean Geotechnical Society
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    • v.23 no.10
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    • pp.23-31
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    • 2007
  • Although the relative density is an important factor showing mechanical properties of granular soils, the methods for its estimation have not been satisfactorily standardized. Many researchers have proposed various methods to determine max, and min, dry density, but the results, especially for max, dry density, show significant differences. In this study, a simple and practical method of evaluating the max, relative density was proposed, which could give reliable results in comparison with conventional methods. The experiment was carried out by varying the number of blows and the layers of the sample for each mold and the results were compared with those of Bowles method.

Selective Concentration of Viable Spermatozoa by Standardized Glass-wool Column and Its Use for IVF (Standardized Glass-wool Column을 이용한 운동성 정자의 선택적 분리 및 이의 체외수정에의 이용)

  • Kim, Sun-Haeng;Ku, Pyung-Sham
    • Clinical and Experimental Reproductive Medicine
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    • v.15 no.2
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    • pp.149-155
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    • 1988
  • To increase fertilization rate in vitro, separation of viable spermatozoa from the seminal plasma and its other components may be a useful procedure. Ejaculates from healthy men, whose semen analysis findings were normal in 19, and abnormal in 10, were filtered using the glass-wool filtration technique to yield a concentrated, viable sperm samples for IVF, and the usefulness and safety of this method were evaluated. The recovery rate of motile sperm in abnormal groups was 46.2% and 54.5% in normal group. The % motility was increased significantly compared with original sample after filtration, and the grade motility was improved, too. The sperm population with normal morphology was also increased significantly in both group. Using transmission electron microscopy, the ultrastructural integrity of acrosomal segment was examined in order to evaluate the potentially hazardous effect of glass-wool filtration to sperm head, however, sperm population with normal ultrastructure was increased compared with that of original ejaculate after separation. The filtered sperm was then processed for IVF, as the fertilizing capacity is the ultimate parameter of the sperm function. In abnormal group, the fertilization rate(41.5 %) and the ET rate per stimulated cycle were much lower than that of mormal group(69.6%). However, the cleavage rate and the number of embryos transfered per ET cycle were comparable with those of nomal group. The results suggest that the glass-wool filtration of sperm, particularly in oligo-asthenozoospsrmia, may be useful and safe method in the preparation of sperm for IVF.

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