• Title/Summary/Keyword: S/Z ratio

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브래드포드법칙과 그 응용에 관한 고찰

  • 이경호
    • Journal of Korean Library and Information Science Society
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    • v.8
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    • pp.127-154
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    • 1981
  • Today's complicated society with a rapid change needs more objective and accurate data for the better managerical decisions and the prospect for the future other than the intuition or subjective experience by men themselves. These data can't be extracted without the analysis of actual data by a n.0, pplying any of mathematical techniques. One of these mathematical techniques, called bibliometrics has been newly developed in the field of library and information science to extract the objective data for the better services through the library operations. The Beadford's Law, one important law in bibliometrics has provided rather scientific and objective basis on the more valid building of library collection within the constraints of budget. The purpose of the study is to investigate the theory of the Bradford's Law, to clarify the possible areas of its a n.0, pplication, and to discern some problems in doing so. The results of the study can be summarized as follows; (1) There is certain difference between the graphical formulation and verbal formulation of Bradford's Law. But this law is very useful for the field of library and information science, owing to the flexibility of the a n.0, pplication of the law in the field. (2) The minimal nucleus can consist of a single periodical only if j, the number of relevant papers in the most productive journals is greater than Z/2. On the other hand, if j is less than or equal to Z/2, then the minimal nucleus will consist of 2 or more periodicals. (3) It is possible to design the most compact selection of scientific periodicals covering any specified percentage P among the total periodicals by using the formulation, log n=Plog N+(1-P)logs, or Nlog N/s=P center dot N log N/s. (4) If there is need to provide all the articles needed by users the given budget, the library can purchase the proper number of journals, by using the formulation, f center dot AN=An+PN (log N/s-logn/s). (5) In the building of the library collection based on the decreasing ratio of use, the library can subscribe to the proper number of journals according to the satisfactory degree of the need, by using the formulation, f=Nu+uNlogN/S-uNlogn/s / nNlogN/s = 1+logN/m /logN/s (6) If the order of valuable journals is decided according to the frequency of being cited, the order can't always represent the value. (7) The evaluation criteria for the journals with high value, but less cited should be made a further study.

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The Chemical Composition of V1719 Cyg: δ Scuti Type Star without the Accretion of Interstellar Matter

  • Yushchenko, Alexander V.;Kim, Chulhee;Jeong, Yeuncheol;Doikov, Dmytry N.;Yushchenko, Volodymyr A.;Khrapatyi, Sergii V.;Demessinova, Aizat
    • Journal of Astronomy and Space Sciences
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    • v.37 no.3
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    • pp.157-163
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    • 2020
  • High resolution spectroscopic observation of V1719 Cyg were made at 1.8 meter telescope of Bohyunsan Optical Astronomy observatory in Korea. Spectral resolving power was R=45,000, signal to noise ratio S/N>100. The abundances of 28 chemical elements from carbon to dysprosium were found with the spectrum synthesis method. The abundances of oxygen, titanium, vanadium and elements with Z>30 are overabundant by 0.2-0.9 dex with respect to the solar values. Correlations of derived abundances with condensation temperatures and second ionization potentials of these elements are discussed. The possible influence of accretion from interstellar environment is not so strong as for ρ Pup and other stars with similar temperatures. The signs of accretion are absent. The comparison of chemical composition with solar system r- & s-process abundance patterns shows the enhancement of the photosphere by s-process elements.

An Experimental Study on Flame Structure and Combustion Characteristics of Turbulent Diffusion Flame(I) (난류확산화염의 화염구조와 연소특성에 관한 실험적 연구)

  • Choe, Byeong-Ryun;Jang, In-Gap;Choe, Gyeong-Min
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.3
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    • pp.1028-1039
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    • 1996
  • This study was focused on the examination of the flame structure and the combustion characteristics of diffusion flame which was formed the turbulent shear flow of a double coaxial air jet system. The shear flow was formed by the difference velocity of surrounding air jet(U$\_$s/) and center air jet (U$\_$c/). So experimental condition was divided S-type flame (.lambda. > 1) and C-type flame (.lambda. < 1) by velocity ratio .lambda. (=U$\_$s//U$\_$c/). For examination of the flame structure and the combustion characteristics in diffusion flame, coherent structure was observed in flame by schlieren photograph method. We measured fluctuating temperature and ion current simultaneously and accomplished the statistical analysis of its. According to schlieren photograph, the flame was stabilized in the rim of the direction of lower velocity air jet, coherent eddy was produced and developed by higher velocity air jet. The statistical data of fluctuating temperature and ion current was indicated that reaction was dominated by higher velocity air jet. The mixing state of burnt gas and non-burnt gas was distributed the wide area at Z = 100 mm of C-type flame.

Analysis of instrument exercise using IMU about symmetry

  • Yohan Song;Hyun-Bin Zi;Jihyeon Kim;Hyangshin Ryu;Jaehyo Kim
    • International Journal of Advanced Culture Technology
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    • v.11 no.1
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    • pp.296-305
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    • 2023
  • The purpose of this study is to measure and compare the balance of motion between the left and right using a wearable sensor during upper limb exercise using an exercise equipment. Eight participants were asked to perform upper limb exercise using exercise equipment, and exercise data were measured through IMU sensors attached to both wrists. As a result of the PCA test, Euler Yaw(Left: 0.65, Right: 0.75), Roll(Left: 0.72, Right: 0.58), and Gyro X(Left: 0.64, Right: 0.63) were identified as the main components in the Butterfly exercise, and Euler Pitch(Left: 0.70, Right 0.70) and Gyro Z(Left: 0.70, Right: 0.71) were identified as the main components in the Lat pull down exercise. As a result of the Paired-T test of the Euler value, Yaw's Peak to Peak at Butterfly exercise and Roll's Mean, Yaw's Mean and Period at Lat pull down exercise were smaller than the significance level of 0.05, proving meaningful difference was found. In the Symmetry Index and Symmetry Ratio analysis, 89% of the subjects showed a tendency of dominant limb maintaining relatively higher angular movement performance then non-dominant limb as the Butterfly exercise proceeds. 62.5% of the subjects showed the same tendency during the Lat pull down exercise. These experimental results indicate that meaningful difference at balance of motion was found according to an increase in number of exercise trials.

Fabrication of Ceramic-based Graphene Membrane (CbGM) and Its Mass Transport Behavior for Water Treatment (수처리용 세라믹 기반 그래핀 맴브레인의 합성 및 물질이동특성)

  • Kim, Chang-Min;Park, Ki-Bum;Kim, Kwang-Soo;Kim, In S.
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.11
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    • pp.649-655
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    • 2015
  • As a novel water treatment membrane, concept of ceramic-based graphene membrane (CbGM) was suggested, and its mass transport behavior was investigated. The selectivity of CbGM was given by graphene material which is consisting of active layer, only transmitting water, but rejecting salts. Filtration-assisted assembly methods was employed as a facile method to fabricate CbGM. Surface morphology and characteristics of CbGM were analyzed by scanning electron microscopy (SEM) and contact angle. In addition, three different kinds of solutes (i.e., NaCl, $MgCl_2$, $Na_2SO_4$) were tested in batch forward osmosis system to confirm the mass transport behavior. Through surface morphology analysis and mass transport behavior, it was revealed that interlocking between graphene layers is very important, rather than thickness of laminated graphene layers, in terms of selectivity to CbGM. All the anions in each solute showed faster transport than those of cations. In addition, solutes which have high ion valence charge ratio of anion to cation ($Z^-/Z^+$) was easier to be passed through CbGM. It indirectly implied that the surface charge of CbGM appear to be positive. In addition, It showed that surface charge of CbGM has a great role on mass transport, in particular, transport of matter having charges, generally ions.

Studies on the Engineering Characteristics of Alluvial Clayey Deposits in the Bay Area of Asan (II) (아산만지역 충적점토의 토질특성에 관한 연구(II))

  • 유능환;유연택
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.30 no.2
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    • pp.55-66
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    • 1988
  • This study was conducted to investigate the various engineering properties and correlationshops among the soil constants of alluvial clayey deposits distributed in the bay of Asan and their results are summarized as follows : 1. Grain size distribution of soil was consisted of 12 % of clay, 46-73 % of silt, 2-23 % of sand, and as for the consistency characteristics, 26-36 % of liquid limit, 18-21 % of plastic limit and 6-16 % of plastic index, and so the soil belonging to as a lower plastic nonorganic clay, it's specific gravity was 2,66-2.70, and the location on the plastic chart was approximately above the A-line. Z The natural moisture content and unit weight were 30-43 % and 1.76-1.87 g I cm$_3$, respectively, and according to increment of natural moisture content, the unit weight was decreased, and the initial void ratio and degree of saturation were shown of 0,87-1119 and 92- 100 %, most of saturated. 3. Cone resistance value which was shown 2.4 - 6.5 kg / $cm^2$ was a little lower and it was increased with the depth of layer and shown the formular $q_c=0.7_z+1.32$. 4. Unconfined compression strength was about 0.18-0.43kg /$cm^2$, cu, 0.1-0.22kg / $\psi$, $2-6^{\circ}$ under uu-test condition of triaxial, and CCU, 0.08-0.3 kg/cm , $\psi$, $12-18^{\circ}$ under the condition of cu-test. 5. Pre-consolidation load of characteristics of consolidation was 0.4-0.8 kg / $cm^2$, compression index, about 0.17-0.33. 6. Liquid limit and plastic index were incresased with the increment of clay content but most of alluvial clay was appeared as a normal through non-activity clay soil shown more natural moisture content than liquid limit, and their relationship as follows : LL=0.38( cy+54.8), PI=0.836(LL -17.8), PI =0.468(LL -0.48) 7. The initial void ratio presented correlationship of positive among clay content, natural moisture content and liquid limit, and that of reverse with unit weight, and their results as follws : $e_o=0.024(w_n+0.2)$, $e_o=e_o=0.0003c_y+0.0005 LL+0.0151 W_n+\frac{3.58}{r-t}-1.52$ 8. It was shown that the compression index has correlationship of postive among the clay content, liquid limit, plastic index, natural moisture content and initial void ratio, and their relationships as follows ; $c_c=0.44(e_o-0.47)$, $c_c=0.001$

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TRANSLUCENCY OF LIGHT CURED COMPOSITE RESINS DEPENDS ON THICKNESS & ITS INFLUENCE ON COLOR OF RESTORATIONS (광중합복합레진의 두께에 따른 투명도 차이가 수복물의 색상에 미치는 영향)

  • Hwang, In-Nam;Lee, Kwang-Won
    • Restorative Dentistry and Endodontics
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    • v.24 no.4
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    • pp.585-603
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    • 1999
  • Esthetic availabilities used as an esthetic restorative maternals can be determined by the optical coincidence among materials, enamel and dentin. Enamel is highly translucent. That's why esthetic materials need to correspond the close translucency of enamel. But the translucent materials are affected by the background color. So it should be predicted that the color of estorative materials depend on the any thickness and the spectral reflectance of the background on which they are placed. The object of this investigation, under above hypothesis, was to determine and analyze how they affect the final color according to the thickness, translucency and background color (white, black and dentin) fill three commercial light cured composite resins(Charisma, Spectrum TPH and Z100). And correlation was analyzed to find out the possibility of the prediction when using the certain background color and thickness of materials. Followings are the result 1. The I shade of CHA showed the lowest contrast ratio($Co_7$) while the B3 shade of Z100 showed the highest contrast ratio(p<0.05). 2. The value of $L^*$ and $b^*$ on the white and dentin background is increased with decreasing thickness. And there are significant relationships between increasing thickness and each value(R>0.085). But there is a little change of $L^*$ and $b^*$ value on the black background regardless of the thickness(p>0.05). 3. For the $a^*$ value, there was little difference in values as a function of thickness and changed irregularly regardless of thickness in all background. 4. The pattern of increasing value of $L^*$ and $b^*$ with decreasing thickness was similar to the group of white and dentin background. In both dentin one showed lesser change of value. 5. The values of $L^*a^*b^*$ measured on the different background with same thickness showed the recognizable color difference(${\Delta}E^*$>2) when the thickness was below 2.6mm. 6. Contrast ratio was increased with increasing thickness with significant relationship (R>0.9). 7. Spectral reflectance of composite resins that calculated from Kubelka-Munk equation was showed little difference compared with observed value w1th decreasing thickness.

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Association between PCR-RFLP Polymorphisms of Five Gene Loci and Milk Traits in Chinese Holstein

  • Zhang, R.F.;Chen, H.;Lei, C.Z.;Fang, X.T.;Zhang, Y.D.;Hu, S.R.;Su, L.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.2
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    • pp.166-171
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    • 2007
  • The objective of this study was to assess the association of polymorphisms in ${\kappa}$-cn, ${\beta}$-lg, ${\beta}$-lg 5′ flanking region, CSN1S2, and IGFBP-3 genes with milk production traits and mastitis-related traits in Chinese Holstein. Traits analyzed were 305 day standard milk yield, protein percentage, fat percentage, the ratio of fat percentage and protein percentage, pre-somatic cell count, somatic cell count, and somatic cell score, respectively. CSN1S2 locus was uninformative because only one genotype BB was found in Chinese Holstein. Allele frequencies of A and B in IGFBP-3 gene were 0.5738 and 0.4262 in Chinese Holstein population, which was different from reported Qinchuan cattle population. The genotypes of animals at IGFBP-3 locus significantly affected 305 day standard milk yield, protein percentage, and somatic cell score. The ${\beta}$-lg genotypes had a significant effect on protein percentage and the ratio of fat percentage and protein percentage. Polymorphism in ${\beta}$-lg 5′ flanking region was associated with 305 day standard milk yield, protein percentage, fat percentage, pre-somatic cell count, and somatic cell count. No significant associations of the polymorphism in ${\kappa}$-cn gene were observed for any trait.

Survey on Nutritional Status of Pre-school Children in Asan Measured by Anthropometric and Nutrient Intake Analysis (아산시 거주 미취학 아동들의 신체계측 및 영양상태 조사)

  • Kim, Hui-Seon;Lee, Hyeon-Ok
    • Journal of the Korean Dietetic Association
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    • v.11 no.1
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    • pp.114-124
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    • 2005
  • The nutritional status of pre-school children is important for both physical growth and functional development. This study investigated the anthropometric, nutrient intakes and dietary quality of the pre-school children living in Asan for planning nutritional education program. The dietary intakes were measured by 2-day 24 hr recall recorded by children's mothers and the anthropometric data were collected by measuring children's weights, heights, and percent body fat at Asan Public Health Center. The children were 161 boys and 129 girls aged 5 and 6 years. When children's nutritional status was determined by their anthropometric status (underweight, normal weight and overweight) determined by z-score (normal range between -1.00 and 1.00), only 1.4% of the children belonged to underweight group while 55.7% and 42.9% belonged to normal and overweight groups, respectively. Significantly higher number of children belonged to overweight group for 5 year-olds. No differences were observed in nutrient intakes, nutrient adequacy ratio (NAR) and index of nutritional quality (INQ) values among nutritional status groups. Intakes of the most nutrients were adequate, but NAR and INQ of calcium and zinc were low. When nutrient intakes, NAR and INQ were compared by sex or age, all nutrient intakes were appropriate except calcium and zinc intakes of 6 year-olds. Nutrient intakes of 5 years were higher than those of 6 years. The mean of nutrient adequacy ratio (MAR) was 0.85 and mean INQ was 1.51 for all participants. The nutritional management program for pre-school children in Asan would be directed differently by age groups and education material should contain contents educating to consume moderate amount of food for 5 year-olds and to increase intake of foods with mineral nutrients such as calcium and zinc for 6 year-olds.

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Spatial Analysis of Colorectal Cancer Cases in Kuala Lumpur

  • Shah, Shamsul Azhar;Neoh, Hui-Min;Syed Abdul Rahim, Syed Sharizman;Azhar, Zahir Izuan;Hassan, Mohd Rohaizat;Safian, Nazarudin;Jamal, Rahman
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.3
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    • pp.1149-1154
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    • 2014
  • Background: In Malaysia, data from the Malaysian Health Ministry showed colorectal cancer (CRC) to be the second most common type of cancer in 2007-2009, after breast cancer. The same was apparent after looking at males and females cases separately. In the present study, the Geographic Information System (GIS) was employed to describe the distribution of CRC cases in Kuala Lumpur (KL), Malaysia, according to socio-demographic factors (age, gender, ethnicity and district). Materials and Methods: This retrospective review concerned data for patients diagnosed with colorectal cancer in the years 1995 to 2011 collected from the Wilayah Persekutuan Health Office, taken from the cancer notification form (NCR-2), and patient medical records from the Surgical Department, Universiti Kebangsaan Malaysia Medical Centre (UKMMC). A total of 146 cases were analyzed. All the data collected were analysed using ArcGIS version 10.0 and SPSS version 19.0. Results: Patients aged 60 to 69 years accounted for the highest proportion of cases (34.2%) and males slightly predominated 76 (52.1%), Chinese had the highest number of registered cases at 108 (74.0%) and staging revealed most cases in the 3rd and 4th stages. Kernel density analysis showed more cases are concentrated up in the northern area of Petaling and Kuala Lumpur subdistricts. Spatial global pattern analysis by average nearest neighbour resulted in nearest neighbour ratio of 0.75, with Z-score of -5.59, p value of <0.01 and the z-score of -5.59. Spatial autocorrelation (Moran's I) showed clustering significant with p<0.01, Z score 3.14 and Moran's Index of 0.007. When mapping clusters with hotspot analysis (Getis-Ord Gi), hot and cold spots were identified. Hot spot areas fell on the northeast side of KL. Conclusions: This study demonstrated significant spatial patterns of cancer incidence in KL. Knowledge about these spatial patterns can provide useful information to policymakers in the planning of screening of CRC in the targeted population and improvement of healthcare facilities to provide better treatment for CRC patients.