• Title/Summary/Keyword: K-values

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Effects of Size and Permittivity of Rat Brain on SAR Values at 900 MHz and 1,800 MHz

  • Hyun Jong-Chul;Oh Yi-Sok
    • Journal of electromagnetic engineering and science
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    • 제6권1호
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    • pp.47-52
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    • 2006
  • The objective of this study is to evaluate the effects of size and permittivity on the specific absorption rate(SAR) values of rat brains during microwave exposure at mobile phone frequency bands. A finite difference time domain (FDTD) technique with perfect matching layer(PML) absorbing boundaries is used for this evaluation process. A color coded digital image of the Sprague Dawley(SD) rat based on magnetic resonance imaging(MRI) is used in FDTD calculation with appropriate permittivity values corresponding to different tissues for 3, 4, 7, and 10 week old rats. This study is comprised of three major parts. First, the rat model structure is scaled uniformly, i.e., the rat size is increased without change in permittivity. The simulated SAR values are compared with other experimental and numerical results. Second, the effect of permittivity on SAR values is examined by simulating the microwave exposure on rat brains with various permittivity values for a fixed rat size. Finally, the SAR distributions in depth, and the brain-averaged SAR and brain 1 voxel peak SAR values are computed during the microwave exposure on a rat model structure when both size and permittivity have varied corresponding to different ages ranging from 3 to 10 weeks. At 900 MHz, the simulation results show that the brain-averaged SAR values decreased by about 54 % for size variation from the 3 week to the 10 week-old rat model, while the SAR values decreased only by about 16 % for permittivity variation. It is found that the brain averaged SAR values decreased by about 63 % when the variations in size and permittivity are taken together. At 1,800 MHz, the brain-averaged SAR value is decreased by 200 % for size variation, 9.7 % for permittivity variation, and 207 % for both size and permittivity variations.

A comparative study on the accuracy of the devices for measuring the implant stability

  • Cho, In-Ho;Lee, Young-Il;Kim, Young-Mi
    • The Journal of Advanced Prosthodontics
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    • 제1권3호
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    • pp.124-128
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    • 2009
  • STATEMENT OF PROBLEM. How the ISQ values measured by $Osstell^{TM}$ and $Osstell^{TM}$ Mentor are related, and whether the ISQ values acquired from the two machines changes in accordance with changes in implant stability are not yet fully understood. PURPOSE. The aim of this study was to find out correlation between the ISQ values acquired from $Osstell^{TM}$ and $Osstell^{TM}$ Mentor, and to evaluate the clinical effectiveness and accuracy of two devices. MATERIAL AND METHODS. Sixty two implants were inserted into 47 patients, and their ISQ values were measured using $Osstell^{TM}$ and $Osstell^{TM}$ Mentor. In the first stage surgery, the ISQ values of forty four implants inserted into thirty five patients were measured. In the second stage surgery, the values of fifty implants inserted into thirty seven patients were measured. The values were analyzed to determine the difference between the mean ISQ values of $Osstell^{TM}$ and $Osstell^{TM}$ Mentor. In addition, the correlation between implants used in the first and second stage of surgery with regard to their types and areas of insertion were analyzed. The difference between the ISQ values of 32 implants in each patient during the first and second stage was analyzed. The statistical assessment was carried out using SPSS V. 12.0 for Win. (SPSS Inc., Chicago, USA). The Pearson correlation coefficient was used to examine the correlation between $Osstell^{TM}$ and $Osstell^{TM}$ Mentor in the first and second stages of surgery, whereas the difference between their ISQ values was evaluated using a paired t-test. RESULTS. In the first stage, the mean ISQ value for $Osstell^{TM}$ and $Osstell^{TM}$ Mentor was 70.84 and 75.09, respectively, showing a significant difference (P < .01). In the second stage, the mean ISQ value of $Osstell^{TM}$ and $Osstell^{TM}$ Mentor was 71.76 and 75.94, respectively, also showing a significant difference (P < .01). The difference between the ISQ values in patients in the first and the second stages was significant with both instruments. CONCLUSION. The significant difference in the values obtained using the $Osstell^{TM}$ and $Osstell^{TM}$ Mentor between the first and second stages of implant surgery indicates that these values can be a convenient and precise way for evaluating the implant stability in clinical practice.

진도견(珍島犬)의 혈액상(血液像) 및 혈액화학치(血液化學値)에 관(關)한 연구(硏究) 제삼보(第三報) 진도견(珍島犬)의 혈청전해질치(血淸電解質値) (Studies on Hematologic Values and Blood Chemistry Values of Normal Jindo Dogs 3. Serum Electrolyte Values for Adult Jindo Dogs)

  • 박남용;임봉호;조성만
    • 대한수의학회지
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    • 제20권2호
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    • pp.175-178
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    • 1980
  • Normal values of serum electrolytes were determined for adult 36 females and 18 males, 1 to 6 years old, of Jindo dogs. The mean values, standard deviation and rangEs of sodium, potassium, chloride, calcium and inorganic phosphorus were studied and data analyzed to determine whether differences existed between the values of female and those of male dogs. The results obtained in this study were as follows: 1. The mean value of serum sodium was $143{\pm}1.5mEq/liter$, ranged from 138mEq/liter to 152 mEq/liter. The mean values for the females and males were $144{\pm}2.0mEq/liter$ and $142{\pm}1.7mEq/liter$, respectively. They showed that the female dogs had a tendency toward higher values than the male dogs, but no significant sex-related differences were observed. 2. The mean value of serum potassium was $4.6{\pm}0.2mEq/liter$, ranged frem 3.5mEq/liter to 6.0mEq/liter. The mean values for the females and males were $4.7{\pm}0.4mEq/liter$ and $4.5{\pm}0.3mEq/liter$. They showed that the female dogs had a tendency toward higher values than the male dogs, but sex differences were not found to be significant. 3. The mean value of serum chloride was $103{\pm}3.0mEq/liter$ ranged from 95mEq/liter to 117mEq/liter. The mean values for the females and males were $103{\pm}3.2mEq/liter$ and $103{\pm}3.3mEq/liter$, no sex differences showed. 4. The mean value of serum calcium was $5.2{\pm}0.1mEq/liter$ ranged from 4.7mEq/liter to 5.8mEq/liter. The mean values for the females and males were $5.4{\pm}0.1mEq/liter$ and $5.2{\pm}0.09mEq/liter$ respectively, no significant sexd iffere-nces were observed. 5. The mean value of serum inorganic phosphorus was $4.3{\pm}0.7mg/100ml$, ranged from 2.5mg/100ml to 5.8mg/100ml. The mean values for the females and males were $4.3{\pm}0.9mg/100ml$ and $4.1{\pm}0.8mg/100ml$, respectively, no sex differences showed.

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Effect of pH on Rheological Properties of Dysphagia-Oriented Thickened Water

  • Yoon, Seung-No;Yoo, Byoungseung
    • Preventive Nutrition and Food Science
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    • 제21권1호
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    • pp.73-77
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    • 2016
  • Flow and dynamic rheological properties of thickened waters prepared with commercial food thickeners were investigated at different pH levels (3, 4, 5, 6, and 7). The commercial xanthan gum (XG)-based thickener (thickener A) and starch-based thickener (thickener B), which have been commonly used in a domestic hospital and nursing home for patients with swallowing difficulty (dysphagia) in Korea, were selected in this study. Thickened samples with both thickeners at different pH levels showed high shear-thinning flow behaviors (n=0.08~0.22). Thickened samples at pH 3 showed higher n values and lower consistency index (K) values when compared to those at other pH levels. The K values of thickener A increased with an increase in pH level, while the n values decreased, showing that the flow properties greatly depended on pH. There were no noticeable changes in the K values of thickener B between pH 4 and 7. At pH 3, the thickened water with thickener A showed a higher storage modulus (G') value, while that with thickener B showed a lower G'. These rheological parameters exhibited differences in rheological behaviors between XG-based and starch-based thickeners, indicating that the rheological properties of thickened waters appear to be greatly influenced by the acidic condition and the type of food thickener. Appropriately selecting a commercial food thickener seems to be greatly important for the preparation of thickened acidic fluids with desirable rheological properties for safe swallowing.

발효쪽 추출물의 생리적 기능과 염색특성(제2보) (A Study on the Physiological Effects and Dyeing Properties of the Extract of Fermented Indigo(Part II))

  • 한신영;최석철
    • 한국의류학회지
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    • 제24권8호
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    • pp.1146-1154
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    • 2000
  • The purpose of this study was to investigate the antimicrobial activity, antimutagenic and anticancer effects and dyeing properties of the fermented indigo extract. The methanol extract of fermented indigo showed a strong inhibition effect on Trich. mentagrophytes and antimutagenic activities against aflatoxin B$_1$(AFB$_1$) in the Ames test using Salmonella typhimurium TA 100. We also found in vitro anticancer effects of the methanol extract of fermented indigo and it was evaluated by using Clone M-3 mouse melanoma cells and A431 human epidermoid carcinoma cells and exerted little cytotoxity against 3T3-L1 embryo fibroblast cell. In the relationship between the K/S values of cotton and silk fabrics dyed with fermented indigo and dyeing repeating times, the K/S values became higher as the repeating times were increased. The K/S values were high when the fabrics were dyed at low temperture. The K/S values of cotton fabrics were higher than those of silk fabrics. Changes of surface color of silk fabrics were higher than those of cotton fabrics after water fastness test, laundering, irradiation and treatment of acidic and alkaline perspiration.

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편마비 환자의 보행 동안 양하지 관절의 돌림힘과 일률 (Moment and power of lower extremities during hemiplegic gait)

  • 권영실;강기창;정병옥;박래준;김진상
    • The Journal of Korean Physical Therapy
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    • 제11권1호
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    • pp.55-61
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    • 1999
  • The purpose of this study was to compare the moment and power of affected Side and those of unaffected side during gait in hemiplegic patients after stroke. Force plate ana kinetic gait analysis was used. The following is resulted from this study. 1. In the hip joint, moment values had not difference between affected side and unaffected side. Power values had difference between affected and unafected side. 2. In the knee joint, moment values and power values had difference between affected side and unaffected side. 3. In the ankle feint, moment and power values had not, difference between affected side and unaffected side.

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한국인의 영어 폐쇄음 발화의 정확성과 발음 숙련도와의 관계에 관한 연구 (A Study on the Relation Between Korean Speakers' English Stop Pronunciation Accuracy and Pronunciation Proficiency)

  • 김지은
    • 말소리와 음성과학
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    • 제4권3호
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    • pp.51-58
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    • 2012
  • The purpose of this study is to measure the impact of Korean speakers' English stop pronunciation on their general pronunciation proficiency. For these purposes, 20 Korean speakers read English sentences and their pronunciations were rated by native English speakers. The Korean speakers' VOT values of English stops in sentences were then measured and the relation between the VOT values and native speakers' pronunciation rating was compared. Here, the relation between (1) the proficiency score of each speaker and VOT values; and (2) the proficiency score of each sentence and VOT values were analyzed. The results show that there is a relation between the proficiency score of each sentence and VOT values of /t, b, d, g/; and there is a relation between VOT values of /t, b, d, g/ and proficiency scores of each speaker while these is a weak relation between VOT values of /p, k/ and proficiency scores of each speaker.

소비자의 가치 체계가 추구 의복 이미지와 의복 소비 가치에 미치는 영향 (The Influences of Consumers' Value Systems on Pursued Clothing Images and Consumption Values)

  • 임경복
    • 복식문화연구
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    • 제15권5호
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    • pp.810-824
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    • 2007
  • The purpose of this study was to examine the women consumers' pursued clothing images and consumption values according to the value system. The data was obtained from questionnaires filled out by 305 women living in Seoul and Gyung-gi. For data analysis, factor analysis, cronbach's alpha, ANOVA and cluster analysis were used. The results of this study were as follows: First, value, pursued clothing images and clothing consumption values were consisted of various factors. Second, women's values influenced on the pursued clothing images and clothing consumption values. Third, according to value factors, women classified into four groups, And they showed different pursued clothing images and consumption values. Also they were differentiated with shopping frequency and age. Therefore, value system was the important factor which can suggest the women's pursued clothing images and consumption values and marketer should know the value system of targeting consumers.

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Combining Independent Permutation p Values Associated with Mann-Whitney Test Data

  • Um, Yonghwan
    • 한국컴퓨터정보학회논문지
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    • 제23권7호
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    • pp.99-104
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    • 2018
  • In this paper, we compare Fisher's continuous method with an exact discrete analog of Fisher's continuous method from permutation tests for combining p values. The discrete analog of Fisher's continuous method is known to be adequate for combining independent p values from discrete probability distributions. Also permutation tests are widely used as alternatives to conventional parametric tests since these tests are distribution-free, and yield discrete probability distributions and exact p values. In this paper, we obtain permutation p values from discrete probability distributions using Mann-Whitney test data sets (real data and hypothetical data) and combine p values by the exact discrete analog of Fisher's continuous method.

부모의 지지적 양육행동과 청소년의 성가치관 (Parent's Supportive Parenting and Adolescent Sexual Values)

  • 민하영;김경화
    • 아동학회지
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    • 제26권6호
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    • pp.59-71
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    • 2005
  • The purpose of this study was to investigate relationship between parent's supportive parenting and adolescent sexual values. The subjects were 137 adolescents who attended high school in Keoungbok. Statistical techniques were Factor Analysis, Crosstabs, Two-way ANOVA, Scheffe' test, Multiple Regression. The results of this were as follows. First, Adolescents who more perceived supportive parenting from a parent were more likely to consult with parents about one's own sexual problems. Second, There was significant difference in adolescent sexual values by parent's supportive parenting levels or gender. Adolescents who perceived more supportive parenting from parent, or who were boys were more likely to have positive sexual values. But there was no significant interaction effect of supportive parenting level and gender on adolescent sexual values. Finally, The Multiple Regression analysis showed that gender was the stronger predictor of adolescent sexual values than parent's supportive parenting.

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