• Title/Summary/Keyword: condition factor (k)

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Optimal Condition of Microporous Membrane for Bone Marrow Stromal Cell Allotransplantation to Stimulate Wound Healing in Vitro (창상치유목적의 골수기질세포 동종이식을 위한 고분자막의 조건)

  • Lee, Eun-Sang;Kim, Myeong-Joo;Han, Seung-Kyu;Hong, Sung-Taek;Kim, Woo-Kyung
    • Archives of Plastic Surgery
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    • v.37 no.5
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    • pp.509-518
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    • 2010
  • Purpose: Major drawbacks of conventional bone marrow stromal cells (BSCs) transplantation method are mainly caused by direct transplanted cell to host cell interactions. We hypothesized that separation of the transplanted cells by a microporous membrane might inhibit most of the potential adverse effects and induce superior effect. The purpose of the study is to determine the optimal condition of the microporous membrane. Methods: First, BSCs were placed in polyethylene terephthalate (PET) transwell inserts with 3, 8, or $12{\mu}m$ pore size, and cultured in 24 well culture plates. After 5 days, bottoms of the plates were observed for presence of attached BSCs in monolayer and cell numbers were evaluated. Second, BSCs were placed PET, polycarbonate (PCT), and mixed cellulose esters (MCE) transwell inserts with 3 and $8{\mu}m$ pore size, and cultured in 24 well culture plates. After 3 days, the supernatants of the media left in culture plate were analyzed for collagen, vascular endothelial growth factor (VEGF), platelet derived growth factor BB (PDGF-BB), and basic fibroblast growth factor (bFGF). Third, BSCs were placed in 15% and 70% of the PET membrane with $3{\mu}m$ pore size. All the experimental conditions and methods were same as the second study. Results: The optimal pore sizes to prevent BSC leakage were $3{\mu}m$ and $8{\mu}m$. The amounts of type I collagen and three growth factors tested did not show significant differences among PET, PCT, and MCE groups. However, the collagen, VEGF, and bFGF levels were much higher in the high (70%) density group than in the low (15%) density group. Conclusion: This study revealed that the optimal pore size of membrane to prevent direct BSC to recipient cell contact is in between $3{\mu}m$ and $8{\mu}m$. Membrane materials and pore sizes do not influence the collagen and growth factor passage through the membrane. The most striking factor for collagen and growth factor transport is pore density of the membrane.

Development of Slope Stability Analysis Method Based on Discrete Element Method and Genetic Algorithm I. Estimation (개별요소법과 유전자 알고리즘에 근거한 사면안정해석기법의 개발 I. 검증)

  • Park Hyun-Il;Park Jun;Hwang Dae-Jin;Lee Seung-Rae
    • Journal of the Korean Geotechnical Society
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    • v.21 no.4
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    • pp.115-122
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    • 2005
  • In this paper, a new method composed of discrete element method and genetic algorithm has been introduced to estimate the safety factor and search critical slip surface on slope stability analysis. In case of estimating the safety factor, conventional methods of slope analysis based on the limit equilibrium do not satisfy the overall equilibrium condition; they must make assumptions regarding the inclination and location of the interstice forces. An alternative slope analysis method based on the discrete element method, which can consider the compatibility condition between force and displacement, is presented. Real-coded genetic algorithm is applied to the search for the minimum factor of safety in proposed analysis method. This search method is shown to be more robust than simple optimization routines, which are apt to find local minimum. Examples are also shown to demonstrate the applicability of the proposed method.

The influence on infant oral health care from mother's experience of oral health education (모친의 구강보건교육경험이 유아의 구강건강관리에 미치는 영향)

  • Park, Chung Soon;Kang, Eun Ju;Song, Ji Yeon;Song, Kwui Sook
    • Journal of Korean society of Dental Hygiene
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    • v.12 no.6
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    • pp.1183-1192
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    • 2012
  • Objectives : This study is for suggesting the data base for help mother and child improve the oral health enhancement action from understanding child's oral health enhancement action from mother's oral health education experience and researching the effects of mother's oral health enhancement action on child's oral health enhancement action. Methods : The subject was 220 children and mothers of some kindergarten in Jeollabuk-do, Korea out of convenience'sampling. The results were collected by carrying out a survey out of self record method from visiting the kindergarten from June 24th to July 12th. and were analyzed. Results : 1. The mother's and child's oral health enhancement action was satisfactory in the factor of 'toothbrushing', 'oral hygiene care item' and 'periodic visits' in case the subjects have experienced oral health education, and that data was meaningful statistically. 2. In the oral health enhancement action practiced by mother to child from existence or absence of the mother's oral health education experience, the data was meaningful statistically in the factor of 'directly brushing its teeth more than once a day', 'washing its tongue' and 'coaching that child could keep the toothbrush not to overlap with other toothbrushes'. 3. In the factor that affect to oral health enhancement action practiced by mother to child, 'toothbrushing' and 'oral hygiene care item' were high level of the mother's oral health enhancement action, and that data was meaningful'statistically. Conclusions : The children's oral health condition could be influenced by mother's oral health knowledges and attention. Accordingly, oral health education for the mother and child has to be enforced'systematically'suited for the characteristic change of oral condition with children age groups. Also, utilizing human resources who have expertise and development of the oral health education program are needed.

Heating Power Consumption Comparison Study Between Static Insulation and Dynamic Insulation at KIER Twin Test Cell (동적 단열재를 적용한 건물에서의 에너지소비량 비교 분석)

  • Kang, Eun-Chul;Park, Yong-Dai;Lee, Euy-Joon;Yun, Tae-Kwon
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.919-924
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    • 2008
  • Power consumption in the building thermal load could be the sum of the building fabric conduction load, building ventilation convection load and other such as radiation loss load. Dynamic Breathing Building (DBB) is the state-of-the-art to improve the wall insulation and indoor air quality(IAQ) performance as making air flow through the wall. This heat recovery type DBB contributes the power consumption saving due to the improved dynamic U-value. KIER twin test cell with static insulation(SI) and dynamic insulation(DI) at KIER was developed to test building power consumption at the real outside conditions. Then, the actual results were compared with the theory to predict the power consumption at the KIER twin test cell and introduced the building new radiation loss factor $\alpha$ to explain the difference between the both the theory and the actual case. As the results, the power consumption at the breathing DI wall building could saved 10.8% at the 2ACH(Air change per hour) compared with conventional insulation. The building radiation loss factor $\alpha$ for this test condition to calibrate the actual test was 0.55 in the test condition.

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Comparison of Quality of Life between Kidney Transplant and Hemodialysis Patients (신장이식환자와 혈액투석환자의 삶의 질 비교)

  • Oh, Sook-Hee;Yoo, Eun-Kwang
    • Journal of Korean Academy of Nursing
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    • v.36 no.7
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    • pp.1145-1153
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    • 2006
  • Purpose: The purpose of this study was to discover kidney transplant and hemodialysis patients' quality of life(QOL) and provide basic data to improve their QOL. Method: One hundred two hemodialysis patients and 106 kidney transplant patients were given a self-administered questionnaire from Mar. 6 to Mar 31, 2006. The instrument consisted of demographic variables, therapeutic-related characteristics and QOL. Collected data was processed using the SPSS 12.0 statistical program for real numbers, percentages, ANCOVA, t-test, ANOVA, Stepwise multiple regression and the Scheffe test. Results: Kidney transplantpatients' QOL was higher than hemodialysis patients. The demographic variables which showed a significant difference in overall QOL were religion, children and monthly income for kidney transplantpatients and educational background for hemodialysis patients. The therapeutic-related variable which showed a significant difference in overall QOL was the patients' perceived health condition for both groups. The influencing factor on overall QOL for both groups was the health condition perceived by themselves. The total variance of the variable for QOL was 42% for kidney transplant patients and 19% for hemodialysis patients. Conclusion: This study revealed that kidney transplant patients have a higher QOL and how patients perceive their health is the strongest influencing factor for QOL. However, there is a large difference between the demand and supply of kidney donors. To solve this problem the standards for donation should be reviewed and revised.

A Study on the Job Stress of Small and Medium Sized Industry Workers (중소규모 제조업 근로자의 직무스트레스 분석)

  • Yun, Soon Nyoung;June, Kyung Ja;Kim, Chun Mi
    • Korean Journal of Occupational Health Nursing
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    • v.6 no.2
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    • pp.79-95
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    • 1997
  • The purposes of this study were to develop a job stress measurement tool and to identify the job stress according to the characteristics of worker and work condition at the small and medium-sized plants. Data were collected through face-to-face survey for April-May, 1997. Subjects were 180 workers at 36 small and medium-sized plants located near Seoul. Data were analyzed by item analysis, factor analysis, and ANOVA. The results were as follow : 1, Number of items of job stress measurement were 33 and Cronbach's $\alpha$ was .9262 except 13 items with low values of Cronbach's coefficient. Factor analysis was done in order for construct validity and 8 factors were extracted and cumulative percent of variance was 65.6%. 2. The job stress scores of male, the younger, 2-shift workers, and over-time workers were significantly higher than those of female, the older, 1-shift workers, and 48 hour workers per week. 3. There were no significant difference between job stress scores and the groups by number of worker, and the types of manufacturing. The stress measurement tool is valid and very reliable to measure worker's stress. Furthermore, the job stress managent program for health promotion of the workers at the vulnerable work condition is needed more and more.

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The Effect of Motor Ability in Children with Cerebral Palsy on Mastery Motivation (뇌성마비 아동의 신체기능이 완수동기에 미치는 영향)

  • Lee, Na-Jung;Oh, Tae-Young
    • The Journal of Korean Physical Therapy
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    • v.26 no.5
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    • pp.315-323
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    • 2014
  • Purpose: This study was conducted in order to investigate the effect of motor ability on mastery motivation in children with cerebral palsy. Methods: Sixty children with cerebral palsy (5~12 years) and their parents participated in the study. Data on general characteristics and disability condition, Gross Motor Functional Classification System, Manual Ability Classification System, and The Dimensions of Mastery questionnaire were collected for this study. Independent t-test, and ANOVA were used for analysis of the effect of The Dimensions of Mastery questionnaire according to general and disability condition, Gross Motor Functional Classification System, and Manual Ability Classification System. Linear regression analysis was performed to determine the effects of Gross Motor Functional Classification System and Manual Ability Classification System on The Dimensions of Mastery questionnaire. SPSS win. 22.0 was used and Tukey was used for post hoc analysis, level of statistical significance was less than 0.05. Results: The Dimensions of Mastery questionnaire score showed statistically significant difference according to gender, region, type, disability rating, Gross Motor Functional Classification System, and Manual Ability Classification System (p<0.05). Gross Motor Functional Classification System and Manual Ability Classification System were the effect factor on The Dimensions of Mastery questionnaire significantly (p<0.05). Conclusion: These results suggest that motor ability of children with cerebral palsy was an important factor having an effect on The Dimensions of Mastery questionnaire.

A Study on the Liquefaction Potential Evaluation of Reclaimed Land Using Laboratory Test and Field Tests (현장 및 실내시험을 이용한 준설매립지반의 액상화 평가에 관한 연구)

  • Kim, Jong-Kook;Chae, Young-Su
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.1528-1537
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    • 2005
  • The purpose of this study is investigated the method for estimation of the liquefaction on the reclaimed land, located in Incheon and assessed the ability of liquefaction under the condition of criteria, which is the magnitude '6.5' of seismic on the basis of the domestic seismic characteristics. Performed not only field test but the experiment as well to study how the fine content would affect into the dreging and reclaimed land and also estimated the safety factor through the empirical method and anticipated detail method based on the results. Within the reclaimed land, there are many sized soils which are almost extended from well-graded silty sand(SM) to poor-graded fine grained sand, and which have the condition, so called, the liquefaction which is easily to bring into under the circumstances within the ground. However, partly, now that the soil is mixed with silt and silty clay which include the content of fine grained dust quite a bit, the difficulties and inconveniences has been expected while trying to find the ratio of cyclic resistance, but finally Seed and Idriss method showed the most way when we estimate the safety factor on the liquefaction.

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Acoustic emission behavior during fatigue crack propagation in 304 Stainless steel (피로균열진전에 따른 304 강의 음향방출 거동)

  • Oh, Kwang-Hwan;Jung, Chang-Kyu;Yang, Yoo-Chang;Han, Kyung-Seop
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.213-219
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    • 2003
  • Acoustic emission behavior during fatigue crack growth test was investigated under various loading condition. To describe the acoustic emission activity, counts rate (d/dn) was related with SIFR (stress intensity factor range, K). Results indicated that SIFR could be divided into two parts according to its relationship with counts rate. For $K<25_{MPa\sqrt{m}}$, counts rate was increased as the SIFR increased. However, for values greater than $25_{MPa\sqrt{m}}$ , decreasing behavior was shown. This behavior of counts rate corresponding SIFR was keeping the same trend regardless of load range or crack length. Acoustic emission response to the single overload was sudden drop and slow recovery in counts rate like crack growth retardation. Under variable loading condition, counts rate of each loading block was same as that of constant amplitude loading. Overall experimental data was somewhat scattered since sensitive characteristics of acoustic emission method. However, these empirical relations indicated that counts rate was uniquely correlate with single parameter, SIFR.

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Study on drilling of CFRP/Ti6Al4V stack with modified twist drills using acoustic emission technique

  • Prabukarthi, A.;Senthilkumar, M.;Krishnaraj, V.
    • Steel and Composite Structures
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    • v.21 no.3
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    • pp.573-588
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    • 2016
  • Carbon Fiber Reinforced Plastic (CFRP) and Titanium Alloy (Ti6Al4V) stack, extensively used in aerospace structural components are assembled by fasteners and the holes are made using drilling process. Drilling of stack in one shot is a complicated process due to dissimilarity in the material properties. It is vital to have optimal machining condition and tool geometry for better hole quality and tool life. In this study the tool wear and hole quality were analysed by experimental analysis using three modified twist drills and online tool condition monitoring using Acoustics Emission (AE) sensor. Helix angle and point angle influence tool performance and cutting force. It was found that a tool geometry (TG1) with high helix angle of $35^{\circ}$ with low point angle $130^{\circ}$ results in reduction in thrust force of 150-500 N range but the TG2 also perform almost similar to TG1, but when compared with the AErms voltage generated during drilling it was found that progressive rise in voltage in TG1 is less with respect to TG2 which can be attributed to tool life. In process wear monitoring was done using crest factor as monitoring index. AErms voltage were measured and correlated with the performance of the drills.