• Title/Summary/Keyword: $C_{}$ f(mean)/

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Evaluation of the Thermal Properties of Disposable Coveralls for Railroad Carriage Maintenance Workers (철도 차량 정비 작업자를 위한 일회용 부직포 작업복의 온열적 성능 평가)

  • 최정화;이주영;김소영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.8
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    • pp.1175-1185
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    • 2004
  • This study evaluated thermo-physiological and subjective properties of improved disposable coveralls for railroad carriage maintenance through climatic chamber trials and a filed study. Subjects wore five kinds of disposable coveralls (Type A: a disposable coverall on the market, Type B: a coverall with an improved hood and size-adjustable design, Type C: a coverall with a portable hood, Type D: a coverall with small holes for ventilation, Type E: a sleeveless coverall, Type F: a separated type of coverall with half sleeves) The air temperature in the climatic chamber was set in 9$^{\circ}C$ and 30$^{\circ}C$ For each condition, subjects simulated the railroad work for 120min. and rectal temperature, skin temperatures, clothing microclimate and subjective sensations were measured. The results of chamber trials showed rectal temperature and clothing microclimate did not display significant differences by clothing type. In 30$^{\circ}C$ air temperature, mean skin temperature was higher in Type E and Type F than in Type A(p<0.05) but between the improved coveralls(B-F), we could not find any significant difference. In the case of thermal comfort, the most preferred types were Type B and Type C in 9$^{\circ}C$ and Type F in 30$^{\circ}C$. All subjects felt more comfortable in the improved coveralls than in coveralls of the market (Type A). In field study, workers preferred Type B, Type C and Type F to Type A but the most favorite type differed by the specific type of work. Especially, workers were dissatisfied that Type D tore easily due to lots of small holes around the armpits and Type I did not protect workers' shoulder and arms from oil contamination. According to the climatic chamber trials and field study, the most effective coveralls were Type B and Type C for winter and Type F for summer.

Application of probabilistic method to determination of aerodynamic force coefficients on tall buildings

  • Yong Chul Kim;Shuyang Cao
    • Wind and Structures
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    • v.36 no.4
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    • pp.249-261
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    • 2023
  • Aerodynamic force coefficients are generally prescribed by an ensemble average of ten and/or twenty 10-minute samples. However, this makes it difficult to identify the exact probability distribution and exceedance probability of the prescribed values. In this study, 12,600 10-minute samples on three tall buildings were measured, and the probability distributions were first identified and the aerodynamic force coefficients corresponding to the specific non-exceedance probabilities (cumulative probabilities) of wind load were then evaluated. It was found that the probability distributions of the mean and fluctuating aerodynamic force coefficients followed a normal distribution. The ratios of aerodynamic force coefficients corresponding to the specific non-exceedance probabilities (Cf,Non) to the ensemble average of 12,600 samples (Cf,Ens), which was defined as an adjusting factor (Cf,Non/Cf,Ens), were less than 2%. The effect of coefficient of variation of wind speed on the adjusting factor is larger than that of the annual non-exceedance probability of wind load. The non-exceedance probabilities of the aerodynamic force coefficient is between PC,nonex = 50% and 60% regardless of force components and aspect ratios. The adjusting factors from the Gumbel distribution were larger than those from the normal distribution.

The Crystal Structure of Nicotine Dihydroiodide (Nicotine Dihydroiodide의 結晶構造)

  • Koo, Chung-Hoe;Kim, Hoon-Sup
    • Journal of the Korean Chemical Society
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    • v.9 no.3
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    • pp.134-141
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    • 1965
  • Crystals of nicotine dihydroiodide, are orthorhombic with space group $p2_12_12_1$.The unit cell of dimensions a=7.61, b=11.01, e=17.27${\AA}$, contains four formula units. The structure has been determined by X-ray diffraction method and has been refined to give the R-index, ${\sum}{\mid}{\mid}F_{\circ}{\mid}-{\mid}F_c{\mid}{\mid}{\div}{\sum}{\mid}F_{\circ}{\mid}$, of 0.16 and 0.14 for $F_{okl}\;and\;F_{hol}$ respectively.The mean lengths of C-C and C-N bonds in pyridine ring are 1.40 and $1.35{\AA}$ and those in pyrolidine ring 1.56 and $1.48{\AA}$ respectively, though accurate measurement of bond length has not been attempted. The six atoms in the pyridine ring are coplanar and on the other hand $C_6,\;C_7,\;C_8$ and $N_2$ atoms in pyrrolidine ring form a plane within accuracy of the analysis, and $C_9$ atom is distant $0.22{\AA}$ out of the plane consist of $C_6,\;C_7,\;C_8$ and $N_2$ aoms. The normals to the two planes form an angle of $94^{\circ}$ with each other. Iodine atom is distant $3.55{\AA}$ from nitrogen atom in pyridine ring and the other iodine atom $3.58{\AA}$ from nitrogen atom in pyrrolidine ring, so that the nitrogen and iodine atoms are firmly linked.It seems that the only forces binding nicotine dihydroiodide molecules together in the crystal are Van der Waals forces.

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Use of the Yeast 1.5-Hybrid System to Detect DNA-Protein-Protein Interaction

  • Kim, Sook-Kyung;Han, Jin-Hee
    • Journal of Microbiology
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    • v.38 no.2
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    • pp.113-116
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    • 2000
  • Escherichia coli F plasmid partition apparatus is composed of two trans-acting proteins (SopA and SopB) and one cis-acting DNA sequence (sopC). The SopB-sopC complex has been suggested to serve a centromere-like function through its interaction with chromosomally encoded proteins which remain to be identified. In this paper, we are introducing a new yeast 1.5-hybrid system which assembles the two-hybrid and one-hybrid system as a mean to find and additional component of the F plasmid partition system, interacting with DNA (sopC)-bound SopB protein. The results indicates that this system is a promising one, capable of selecting an interacting component.

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Spray Characteristics in the cross region of twin spray between impinging F-O-O-F type injectors (충돌형 F-O-O-F 인젝터의 이중분무 중첩영역에서의 분무특성에 관한 연구)

  • Kwon, K.C.;Lee, E.S.;Kang, S.J.;Rho, B.J.
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.758-763
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    • 2001
  • This paper presents twin spray characteristics of two impinging F-O-O-F type injectors in which fuel and oxidizer impinge on each other to atomize under the various conditions. The droplet size and velocity in the impinging spray flow field were measured using a PDPA. The droplet size and velocity were investigated at mixture ratios of 1.5, 2.0, 2.47 and 3.0 for four injectors in which two single F-O-O-F injectors were arranged at intervals of 20.8, 31.2, 41.6 and 62.4mm respectively. In general, the arithmetic mean diameter, SMD and standard deviation of droplet size in the interaction area (X=0 and Y=0mm) were smaller. The axial velocity in the interaction area was slightly higher. Considering the behavior of impinged droplets using the We number calculated by using the axial velocity instead of the relative velocity in line C in Fig. 1(b) for four injectors, it is consumed that the We number over 500 had the possibility to disintegrate, and the We number below 500 had it to cohere after impingement of twin spray. The results of this study can be used for the design of a nozzle for liquid propellant rockets.

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A Study on the Sensory Characteristics of Korean Red Wine (한국산 적포도주의 관능적 특성에 관한 연구 (III))

  • Lee, Jang-Eun;Hong, Hee-Do;Choi, Hee-Don;Shin, Yong-Sub;Won, Yoo-Dong;Kim, Sung-Soo;Koh, Kyung-Hee
    • Korean Journal of Food Science and Technology
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    • v.35 no.5
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    • pp.841-848
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    • 2003
  • The sensory characteristics of red wine Gerbong (G), Campbell (C), Moru (M), Gerbong + Moru (70 : 30, GM), Gerbong + Campbell (70 : 30, GC) and French wine (F, Carbernet Sauvignon, 1998) were evaluated. The preferences of color, flavor, taste and total evaluation were determined by a ranking test, and the organoleptic characteristics were evaluated by a quantitative descriptive analysis (QDA) method. The mean color scores of C, GM, F, GC, M and G were 4.74, 3.94, 4.67, 3.70, 2.65 and 1.47, respectively (p<0.001). The order for the mean score for flavor was GM (4.12) = M (3.94) = C (3.76) = F (3.76) ${\geq}$ GC (3.12)>G (2.29) (p<0.01), and the order for taste was F (4.75) ${\geq}$ C (4.25) ${\geq}$ GM (3.37) = GC (3.50) ${\geq}$ G (2.75) = M (2.37) (p<0.001). The total evaluation of mean scores showed G, M, C, GM, GC and F were 237, 2.44, 4.06, 3.87, 3.64 and 4.81, respectively (p<0.001). Influences of sensory characteristics on the total evaluation, in percentages, were 69.3% for taste, 3.7% for color, and 1.5% for flavor. The influences of taste, color, and flavor in red wine were 17% for sweet, acid, bitter and salty taste, 28.9% for purple and red color, and 14.4% for grape flavor. The attributes of the purple and red colors showed a positive correlation with grape flavor, oak flavor, grape taste, and floral tastes, but a negative correlation with $SO_2$, flavor. The attribute of sweet taste showed a positive correlation with grape flavorand floral flavor, but a negative correlation with bitter and astringency tastes, according to Pearsons correlation analysis (p<0.01).

Genetic Mapping of Resistant Genes in Brassica pekinensis Against Plasmodiophora brassicae Race 6

  • Lee, Gung-Pyo;Baek, Nam-Kwon;Park, Kuen-Woo
    • The Plant Pathology Journal
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    • v.18 no.5
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    • pp.266-270
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    • 2002
  • Inbred lines of Chinese cabbage KU-101 (resistant line against Plasmodiophora brassicae race race 6) and CS-113 (susceptible line) were crossed and their progeny lines F$_1$, BC$_1$F$_1$, F$_2$, and F$_3$ were produced for the construction of the genetic linkage map of R brassicae race 6-resistant Brassica campestris ssp. pekinensis genome. Restriction fragment length polymorphism (RFLP) was applied to compare between parents and their f$_2$ progenies with a total of 192 probes and 5 restriction enzymes. The constructed RFLP map covered 1,104 cM with a mean distance between genetic marker of 8.0 cM, and produced 10 linkage groups having 121 genetic loci. The loci of P. brassicae race 6 (CR6)-resistant Brassica genome were determined by interval mapping of quan-titative trait loci (QTL), which resulted from bioassay using the same race of the fungi in P3 population. Resistant loci were estimated in numbers 1 (Gl) and 3 (G3) linkage groups. In the regression test, Gl had a value of4.8 logarithm of odd (LOD) score, while C3 had values of 4.2-7.2. Given these results, the location of the CR6-resistant loci within the Brassica genome map can now be addressed.

Correlations of Genic Heterozygosity and Variances with Heterosis in a Pig Population Revealed by Microsatellite DNA Marker

  • Zhang, J.H.;Xiong, Y.Z.;Deng, C.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.620-625
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    • 2005
  • Correlation of microsatellite heterozygosity with performance or heterosis was reported in wild animal populations and domestic animal populations, but the correlation with heterosis in a crossbreeding F$_1$ pig population remained uncertain. To explore this, we had random selected and mated Yorkshire${\times}$Meishan (F, n = 82) and their reciprocal (G, n = 47) to F$_1$, and used the two straightbreds as control groups (Yorkshire = 34, Meishan = 55), and observed the heterosis of birth weight (BWT), average daily gain (ADG) and feed and meat ratio (FMR). Two Kinds of measurement-individual heterozygosity (IH) and individual mean d$^2$ (lg value, ID) were used as index of heterozygosity and variance from 39 microsatellite marker loci to perform univariate regression analysis against heterosis. We detected significant correlation of IH with BWT in all of F$_1$ (F+G) and in F. We observed significant correlation of ID with ADG in all of F$_1$ (F+G), and with FMR in all of F$_1$ (F+G) and in F. There was significant maternal effect on heterosis, which was indicated by significant difference of means and distribution of heterosis between F and G. This difference was consistent with distributions of IH and ID, and with difference of means in F and G. From this study, it would be suggested that the two kinds of genetic index could be used to explore the genetic basis of heterosis in crossbreeding populations but could not determine which is better.

Population Ecological Characteristics of the Soft-shelled Clam, Mya japonica in the Intertidal Zone of South Sea in Korea (한국 남해안 조간대에 서식하는 우럭, Mya japonica의 자원생태학적 특성)

  • 이선길;장창익
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.36 no.3
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    • pp.234-243
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    • 2000
  • This paper is to study population ecological characteristics, including growth parameters, survival rate, instantaneous coefficients of natural and fishing mortalities, and age at first capture of the soft-shelled clam, Mya japonioa in the intertidal zone of South Sea in Korea. For describing growth of the clam a von Bertalanffy growth model was adopted, The von Bertalanffy growth curve had an additive error structure and the growth parameters estimated from a non-linear regression were SH/sub ∞/=79.83mm, K=0.26, and t/sub 0/= -0.01. Survival rate (S) of the soft-shelled clam was 0.26 (SD=0.02). The instantaneous coefficients of natural mortality (M) was estimated to be 0.78/year and fishing mortality (F) 0.57/year for the soft-shelled clam. The age at first capture (t/sub c/) was estimated as 2.69 year. The mean densities of the soft-shelled clam by bottom type were 3.40 inds./m²(SE=0.18) in the sand, 63.4 inds./m²(SE= 0.53) in the muddy sand, and 0 inds./m2 (SE=0) in the gravelly sand. The mean densities of the soft-shelled clam by 3 different areas were 4.88 inds./m²(SE=0.09), 2.61 inds./m²(SE=0.13), 7.20 inds./m²(SE=0.18), respectively and the biomass of the clam were estimated as 131mt, 121mt, 665mt, respectively. An yield-per-recruit analysis showed that the current yield-per-recruit of about 8.30g with F=0.57/year and the age at first capture (t/sub c/) 2.69 year, was lower than the maximum possible yield-per-recruit of 9.60g. Fixing to at the current level and increased fishing intensity (F) could produce an increase in the predicted yield-per-recruit from 8.30g to about 9.40. However, estimated yield-per-recruit increased to 1.30g by decreasing to from the current age (2.69 year) to age two with F fixed at the current level. Yield-per-recruit was estimated under harvest strategies based on F/sub max/ and F/sub 0.1/.

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Study on the Behavior of the Fish - 1 . The Swimming Force of Crusian Carp , Carassius Carassius - (어류의 행동에 관한 연구 - 1 . 붕어의 유영력 -)

  • 손태준
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.20 no.1
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    • pp.1-5
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    • 1984
  • The author carried out an experiment for the dynamical swimming force of crusian carp, Carassius carassius. The experimental water tank was made of 4mm thick transparent acryl board in the right hexahedral shape (400L$\times$240W$\times$800H mm). The water temperature in the tank ranged 20.6$^{\circ}C$ to 21.2$^{\circ}C$. The water level in the tank was maintained 70cm high from the bottom. The measurement of the swimming force was carried out by use of strain gauge. The results obtained can be summarized as follows: 1) The momentary maximum swimming force F sub(M) (g) and the sustainable maximum swimming force F sub(s) (g) can be expressed as a function of the body weight W(g). F sub(M) =1.45W, F sub(s) =0.29W where the momentary maximum swimming force means the highest value, and the sustainable maximum swimming force means the mean high value sustained for 4 to 5 seconds presented in the recording paper. 2) F sub(M) and F sub(s) can be expressed as a function of the body length L(cm). F sub(M) =0.11L super(2.63), F sub(s) =0.15L super(1.77) 3) The coefficient of hydraulic resistance for crusian carp was derived as 0.287.

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