• Title/Summary/Keyword: test rate

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Difference in Species of Test Fish on the Determination of Short-term Bioconcentration Factor (단기간 생물농축계수의 측정에 있어서 실험어류의 종에 따른 차이)

  • 민경진;차춘근;전봉식;김근배
    • Journal of Environmental Health Sciences
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    • v.24 no.1
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    • pp.24-31
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    • 1998
  • This study was performed to investigate the difference in species of test fish on the determination of short-term bioconcentration factor in zebrafish(Brachydanio rerio), red sword tail(Xiphophorus hellieri) and goldfish(Carassius auratus). Experimental concentrations of carbamates were 0.05 and 0.10 ppm and chlorothalonil were 0.005 and 0.01 ppm for 3 and 5 days, respectively. This paper reports the measured BCF value on pesticides in various species of test fish, under steady state, and examined correlation between the BCF value and depuration rate constant or LC$_{50}$ or lipid content. Carbamates and chlorothalonil concentration in fish extract and BCF of carbamate and chlorothalonil were increased as incresing test concentration. Carbamates concentration in fish extract and BCF of carbamate were decreased as incresing test period, but chlorothalonil concentration in fish extract and BCF of chlorothalonil were increased as prolonging test period. Determined pesticide concentration in fish extract and BCF were highest in red sword tail, and followed by goldfish, and zebrafish. Determined depuration rate constant were highest in zebrafish, and followed by goldfish, and red sword tail. 96hr-LC$_{50}$ were highest in red sword tail, and followed by zebrafish, and goldfish. Lipid compositions were highest in red sword tail, and followed by goldfish, and zebrafish. Therefore, it is suggested that the difference of BCF between each pesticide due to those of lipid composition of fish and deputation rate constant, while LC$_{50}$ have no effect on BCF.

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A Consolidation Characteristics of Decomposed Mudstone Soil by Constant Rate of Strain Consolidation (일정변형률 압밀시험에 따른 이암풍화토의 압밀특성)

  • 김영수;김기영;김대만
    • Journal of the Korean Geotechnical Society
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    • v.16 no.1
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    • pp.99-106
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    • 2000
  • The main advantage of incremental loading consolidation test is the simplicity of equipments that can be used. However, it is known that the incremental loading test has several deficiencies including long testing time, non-uniform stress state, high and variable rates of strain, very soft clay and problem of back pressure saturation. Due to these drawbacks, various testing methods including constant rate of strain consolidation test(CRS) were developed. In this paper, CRS consolidation test was performed with three different strain rate. The results were verified by the modified CRS theory of Wissa et al.(1971). And then the results obtained from the CRS consolidation tests were compared with those from incremental loading test and direct permeability test.

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A Study on Stress Corrosion Cracking of Fiber Reinforced Composite by Slow Strain Rate Test (저변형률시험법에 의한 섬유강화 복합재료의 응력부식균열에 관한 연구)

  • Lim, Jae-Gyu;Choi, Tae-Su
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.11
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    • pp.3433-3440
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    • 1996
  • This paper was investigation of the stres corrosion cracking(SCC) mechanism and the properties of corrosion fracture surface of glass fiber reinforced plastics(GFRP) produced by hand lay up(HLU) method in synthetic sea water. Test material is GFRP, that was used vinylester type epoxy acrylate resin and an unsaturated polyester as the matrix and the chopped strand mat(CSM) type E-glss fiber as the reinforcement. The slow strain rate test(SSRT) was performed on dry, wet and saturated wet specimens in sea water. Here the pH concentration of synthetic sea water was 8.2 and the strain rate is 1 x $10^{-6}$($sec^{-1}$) and test temperature ranges varied from $-60^{\circ}C$ to $80^{\circ}C$. It could be confirmed the fact that wet specimens tested at a particular test temperature ranges were appeared the eviences of SCC such as con-planar, mirror and hackle zone. Moreover, SCC of GFRP in sea water was characterised by falt fracture surfaces with only small amounts of fiber pull-out, in partial.

A Study on the Properties of the Heavy Duty Rust-Converting Agent used in the Potential Hazard Areas of Fire & Explosion (잠재적 화재.폭발 위험 지역 작업용 녹전환형 중방식 코팅제의 특성에 관한 연구)

  • 강영구
    • Journal of the Korean Society of Safety
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    • v.13 no.3
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    • pp.102-111
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    • 1998
  • This study was concerned with the development of a heavy duty rust-converting agent, the function of which is to form metal complex coatings, containing vinyl halide-acrylic terpolymer emulsion, defoamer, emulsifying agent, glass flakes, chelating agent such as gallotannic acid, gallic acid, and pyrogallic acid, and other additives. The resulted emulsion products(Sample No.1~No.5) were characterized through test either in the forms of emulsions, which include Viscosity, Penetration rate, Acidity and Film drying rate test, or in the forms of coated layer on rusty steel substrates by FT-IR, which include hardness, gloss, salt spray, adhesion and flame retardant test. The test results are as follows ; Penetration rate(0.1~0.4 mm/min), Solid content(70%), Acidity (pH 1.8~2.0), Specific gravity(1.30~1.35), Film drying rate(108min, RH 40% ; 150min, RH 80%), Gloss(83~92, incident angle $60^{\circ}$; 88~97, incident angle $85^{\circ}$), Pencil hardness(4H~5H), Adhesion (100/100), Salt spray test(>720Hr), LOI(%) value(38%), Vertical burning test(UL 94-v-l). According to the various performance of specimens show above, the evaluation of the availability of this heavy duty rust-converting agent can be concluded that all the samples(No.1~No.5) are capable of being used in the field of chemical plant and in the hazard areas of fire and explosion potential. It was observed that the properties of sample No.2, especially gloss and hardness, were much better than that of the other samples.

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Comparison of TVOCs emission characterization of paint and putty according to the amendment of test specimen preparation method (시험편 제작방법 변경에 따른 페인트, 퍼티의 TVOCs의 방출 특성 비교)

  • Park, Joon-Man;Yoo, Ji-Ho;Kim, Man-Goo
    • Analytical Science and Technology
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    • v.23 no.2
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    • pp.109-118
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    • 2010
  • Amended at the Law of indoor air quality management open a court according to the test method and excess standard of the fluid building material were changed. It used the paint and the putty in the fluid building material from this research and comparison of amended and original method it led and in about change direction of amended standard with change of the emission rate who is caused by in the amended test method and excess standard it examined. The reduction emission rate about 45% decreases in the change of test period of the paint, there was not an effect of the emission rate whom it follows in change of dry time. Also change of the emission rate whom it follows in change of application quantity the product which above $5\;mg/m^2h$ has the high emission rate the change of the emission rate is big but there was not change of the emission rate from the products of that others. The putty the emission rate about 61% decreases in case in the change of test period, there was not an effect of the emission rate whom it follows at dry time. The emission rate about 164% increased with increase of application quantity. It tried to compare two test methods, it compared in the paint and putty all current test method it was relaxed the possibility of knowing the thing there was a standard.

Human Papillomavirus Prevalence and Genotype Distribution in Normal and ASCUS Specimens: Comparison of a Reverse Blot Hybridization Assay with a DNA Chip Test

  • Kim, Sunghyun;Lee, In-soo;Lee, Dongsup
    • Biomedical Science Letters
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    • v.21 no.1
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    • pp.32-39
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    • 2015
  • High-risk (HR) human papillomavirus (HPV) genotypes are strongly associated with cervical cancer, whereas other HPV genotypes are not. To identify the various HPV genotypes in clinical samples, we conducted HPV genotyping using a DNA chip test and reverse blot hybridization assay (REBA) in normal cytology samples and atypical squamous cells of undetermined significance (ASCUS) cytology samples. We also investigated the HPV infection rate and HPV genotype prevalence in women with normal cytology and ASCUS cytology. Liquid-based cytology preparations were used for the initial screening of 205 subjects with normal cytology and ASCUS cytology. The HPV infection rate was 49.8% when using the DNA chip assay and 61.0% when using the REBA test. In patients with normal cytology, the HR-HPV positive rate was 21.9% with the DNA chip assay and 43.9% with the REBA test. In contrast, 8.3% of patients with ASCUS were HR-HPV positive when using the DNA chip assay, and 13.6% were positive when tested with the REBA test. The infection rate of HR-HPV in the 40~50-year age group was significantly higher than that of the other age groups. Based on the cytological analysis of the normal and ASCUS samples, the five most prominent HPV genotypes were HPV 16, 18, 68, 33, and 58 using the DNA chip test, and they were HPV 16, 18, 53, 33, and 66 when using the REBA test. In conclusion, the findings show that the results of the REBA test are comparable to those of the DNA chip test. Most strikingly, the REBA test detected the HR-HPV genotype associated with cervical carcinoma similar to that detected with the DNA chip method. Therefore, the REBA test is a useful method to detect clinically important HR-HPV genotypes.

Stress corrosion index of Kumamoto andesite estimated from two types of testing method

  • Jeong Hae-Sik;Nara Yoshitaka;Obara Yuzo;Kaneko Katsuhiko
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.221-228
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    • 2003
  • The stress corrosion index of Kumamoto andesite are evaluated by two types of testing method. One is the uniaxial compression test under various water vapor pressures, and the other is the double torsion (DT) test under a constant water vapor pressure. For the uniaxial compression tests, the uniaxial compressive strength increases linearly with decreasing water vapor pressure on the double logarithmic coordinates. As the results, the stress corrosion index obtained is estimated 44. On the other hand, in the DT test, the relaxation (RLX) test and the constant displacement rate (CDR) test were conducted. For the CDR test, as the displacement rate of loading point increases, the crack velocity increases. However, the fracture toughness is constant regardless of the change in displacement rate and the average fracture toughness is evaluated $2.07MN/m^{3/2}$. For the RLX test, the crack velocity-stress intensity factor curves are smooth and linear. The stress corrosion index estimated from the curves is 37. Comparing stress corrosion indexes in the uniaxial compression test and the DT test, there is no significant difference in these values, and they are considered to be in coincident each other regardless of testing methods. Therefore, it is concluded that stress corrosion is one of material constants of rock.

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STUDY ON THE CARIOGENIC FACTORS IN THE MALE KOREAN TWENTIES (20대 남성의 치아우식발생요인에 관한 연구)

  • Paik Dai-Il
    • The Journal of the Korean dental association
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    • v.15 no.2
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    • pp.145-151
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    • 1977
  • The author performed Snyder test, estimation of salivary flow rate, salivary viscosity test, salivary buffering capacity test, M-R test, oral hygiene ability test, estimation of oral glucose clearance time and plaque reformation test in the 107 male Koreans aged form the age of 20 to 29, in order to detect and control the active cariogenic factors contributing to caries development on the individual basis. Thereafter, the data from 8 kinds of caries activity test were analysed and evaluated. The obtained results were as follows: 1. Snyder test was positive in 86.0% of total tested persons, and among those showing positive Snyder test reaction, slight caries activity was appeared in 39.1%, moderate caries activity in 23.9%, and marked caries activity in 37.0%. 2. Salivary flow rate was under the average flow amount in 53.3%. 3. Salivary buffering capacity was low in 22.4%. 5. Buffering capacity of dental plaque was high in 12.5%. 6. Oral hygiene ability was insufficient in all persons tested. 7. Oral glucose clearance time was long in 42.1%. 8. Plaque reformation rate was high in 8.4% of the 107 persons tested.

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Influence of Evaluation Methods for Fatigue Crack Growth Process (피로균열 성장과정에 대한 평가방법의 영향)

  • 안철봉
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.8 no.1
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    • pp.119-125
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    • 1999
  • The distribution of fatigue crack growth rate is subjected to the measuring interval and calculated method of growth rate. In this paper, in order to establish the method of determining the distribution of fatigue crack growth rate, which ignores those influences, a series of fatigue crack growth experiments and measuring intervals of crack length calculated reasonable are presented. The main conclusions obtained are summarized as follows: 1) As a result of the ΔP constant test and ΔK constant test, it is thought that an approximate measuring interval of 0.3~0.7mm is reasonable, which allows for few errors and is little subjected to the calculated method of crack growth rate. 2) After generally comparing the error estimation by using the experimental data of CCT specimen with the error rating of the CT specimens, it is possible that the fatigue test has few errors within the measuring interval, ξ(Δa/W)=0.0067~0.017, regardless of the dimension of specimen geometry.

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