• Title/Summary/Keyword: initial compliance

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Design Optimization of a Rapid Moving Body Structure for a Machining Center Using G.A. with Variable Penalty Function (가변 벌점함수 유전알고리즘을 이용한 금형가공센터 고속이송체 구조물의 최적설계)

  • 최영휴;차상민;김태형;박보선;최원선
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2003.04a
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    • pp.504-509
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    • 2003
  • In this paper, a multi-step optimization using a G.A.(Genetic Algorithm) with variable penalty function is introduced to the structural design optimization of a high speed machining center. The design problem, in this case, is to find out the best cross-section shapes and dimensions of structural members which minimize the static compliance, the dynamic compliance, and the weight of the machine structure simultaneously. The first step is the cross-section shape optimization, in which only the section members are selected to survive whose cross-section area have above a critical value. The second step is a static design optimization, in which the static compliance and the weight of the machine structure are minimized under some dimensional constraints and deflection limits. The third step is a dynamic design optimization, where the dynamic compliance and the structure weight are minimized under the same constraints as those of the second step. The proposed design optimization method was successful applied to the machining center structural design optimization. As a result, static and dynamic compliances were reduced to 16% and 53% respectively from the initial design, while the weight of the structure are also reduced slightly.

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Patient compliance with supportive periodontal therapy (유지 치주치료에 대한 환자 협조도 분석)

  • Lee, Hye-Won;Park, Jin-Woo;Suh, Jo-Young;Lee, Jae-Mok
    • Journal of Periodontal and Implant Science
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    • v.39 no.2
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    • pp.193-198
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    • 2009
  • Purpose: The purpose of this study was to evaluate the compliance to maintenance schedules recommended supportive periodontal therapy(SPT) and to determine differences in the characteristics of compliant and non-compliant patients. Methods: 414 patients commencing SPT after active periodontal treatment from 2003 to 2005 were included in this study. Based on their compliance with the suggested maintenance schedule, patients were classified as compliant and non-compliant groups. Also patients classified by gender, age, degree of alveolar bone loss and treatment rendered. The association between compliance and patient characteristics was assessed by odds ratio in logistic regression analyses. Results: Only 47% of the initial patient was found to be compliant at the end of August 2008 and 20.8% patients were lost in the first year of SPT. There were significant differences between compliant and non-compliant regard to age, degree of alveolar bone loss and treatment rendered. Conclusions: In conclusion, compliance with SPT generally poor and patients who were older, treated surgical therapy and with mild alveolar bone loss are more compliant to SPT.

Measurement of Dynamic MOE of 3-Ply Laminated Woods by Flexural Vibration and Comparison with Blending Strength and Creep Performances

  • Park, Han-Min;Byeon, Hee-Seop
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.2
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    • pp.46-57
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    • 2006
  • To estimate nondestructively strength performances of laminated woods, 3-ply parallel- and cross-laminated wood specimens exposed under atmosphere conditions after bending creep test were prepared for this study. The effects of density of species, arrangement of laminae and lamination types on dynamic MOE obtained by flexural vibration were investigated, and regression analyses were conducted in order to estimate static bending strength and bending creep performances. Dynamic MOE of parallel-laminated woods showed 1.0~1.2 times higher values than static bending MOE, and those of cross-laminated woods showed 1.0~1.4 times higher values than static bending MOE. The degree of anisotropy of dynamic MOE perpendicular to the grain of face laminae versus that parallel to the grain of face laminae was markedly decreased by cross-laminating. There were strong correlations between dynamic MOE by flexural vibration and static bending MOE (correlation coefficient r = 0.919~0.972) or bending MOR (correlation coefficient r = 0.811~0.947) of 3-ply laminated woods, and the correlation coefficient were higher in parallel-laminated woods than in cross-laminated woods. It indicated that static bending strength performances were able to be estimated from dynamic MOE by flexural vibration. Also, close correlations between the reciprocal of dynamic MOE by flexural vibration and initial compliance at 0.008 h of 3-ply laminated woods were found (correlation coefficient r = 0.873~0.991). However, the correlation coefficient between the reciprocal of dynamic MOE and creep compliance at 168 h of 3-ply laminated woods was considerably lower than those between dynamic MOE and initial compliance, and it was hard to estimate creep compliance with a high accuracy from dynamic MOE due to the variation of creep deformation.

Correlation of Peak Time Shift in Blood Pressure Waveform and PPG Based on Compliance Change Analysis in RLC Windkessel Model

  • Choi, Wonsuk;Cho, Jin-Ho
    • Current Optics and Photonics
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    • v.1 no.5
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    • pp.529-537
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    • 2017
  • We explored how changes in blood vessel compliance affected the systolic rise time (SRT) of the maximum blood pressure (BP) peak wave and the diastolic fall time (DFT) of the minimal BP peak wave, compared to photoplethysmograpic (PPG) parameters, using a two-compartment, second-order, arterial Windkessel model. We employed earlier two-compartment Windkessel models and the components thereof to construct equivalent blood vessel circuits, and reproduced BP waveforms using PSpice technology. The SRT and DFT values were obtained via circuit simulation, considering variations in compliance (the dominant influence on blood vessel parameters attributable to BP changes). And then performed regression analysis to identify how compliance affected the SRT and DFT. We compared the SRTs and DFTs of BP waves to the PPG values by reference to BP changes in each subject. We confirmed that the time-shift propensities of BP waves and the PPG data were highly consistent. However, the time shifts differed significantly among subjects. These simulation and experimental results allowed us to construct an initial trend curve of individual BP peak time (measured via wrist PPG evaluations at three arm positions) that facilitated accurate individual BP estimations.

Experiment Study for Fracture Characterist of the Ash solid (석탄회 고형물의 파괴특성에 관한 실험적 연구)

  • 조병완;박종빈;김효원
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.335-340
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    • 2002
  • By the recently, Environmental pollution is serious by the highly economic growth and expansion of lively country basic industry. Especially, in case of industrial waste and life waste leaped into a pollution source. Also, research for processing of waste and recycling countermeasure is a pressing question on national dimension because it is prohibited an ocean disposal and reclamation. In this study, it looked for fracture characteristic value of recycling a coal ash to decrease environmental pollution by picky and exhaustion of natural resources and to reduce self-weight to prepare for a tall building and earthquake. So a coal ash examined to be possible to do as construction material. It achieved compressive strength test and three points bending test with initial notch depth rate and age for variables to show a basic research data. From the basis of the three points bending test, the fracture parameters - notch sensitivity, fracture energy, initial compliance were experimentally proposed. From the results of the compressive strength test, the elastic modulus was experimentally proposed. Also on the basis of the three points bending test, the fracture parameters - notch sensitivity, fracture energy, initial compliance were experimentally proposed. The results that the strength and fracture energy value are lower than concrete or mortar is described in this paper. Also, it shows that the deflection at fracture decreases as the age increases and the notch sensitivity decrease. However, it is judged to be available to construction material if research is continuously gone forward.

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A Study on the Interlaminar Fracture Toughness of Glass Fiber Reinforced Plastic Comosites (GFRP 복합재료의 층간파괴인성치에 관한 연구)

  • 박기호
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.4
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    • pp.410-420
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    • 1999
  • The value of the mode I interlamina fracture toughness, GIC, is calculated by experimental compliance method, modified compliance method and beam theory. The value of the mode II interlamina fracture toughness, GIC, is evaluated by beam method, theory beam theory and compliance method. This paper describes the effect of load pint displacement rate and speicimen geometries for mode I and II interlaminar fracture toughness of glass fiber reinforced plastic composites by using double cantilever beam (DCB) and end notched flexure (ENF) specimen. For the load point displacement rate of increases whereas the value of 2,6 and 10 mm/min the value of GIC decrease as load point displacement rate increases whereas the value of GIC is found to be no significant effect. The value of GIC decreases as initial crack length increases. The fractured surface of the DCB and ENF samples are examined by scanning electron microscopy (SEM).

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Kinematic Optimum Design of a Torsion-Beam Suspension Using Genetic Algorithms (유전 알고리듬을 이용한 토션빔 현가장치의 기구학적 최적설계)

  • Ok, Jin-Kyu;Baek, Woon-Kyung;Sohn, Jeong-Hyun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.14 no.1
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    • pp.25-30
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    • 2006
  • This study is about an optimum design to improve the kinematic and compliance characteristics of a torsion-beam suspension system. The kinematic and compliance characteristics of an initial design of the suspension was obtained through a roll-mode analysis. The objective function was set to minimize within design constraints. The coordinates of the connecting point between the torsion-beam and the trailing arm were treated as design parameters. Since the torsion-beam suspension has large nonlinear effects due to kinematic and elastic motion, Genetic Algorithms were employed for the optimal design. The optimized results were verified through a double-lane change simulation using the full vehicle model.

Evaluation of J-R Curve for Aluminum 5083 Alloy Weldment by Load Ratio Analysis (Load Ratio 해석에 의한 알루미늄 5083 합금 용접부의 J-R곡선 평가)

  • 윤한기;김연겸
    • Journal of Welding and Joining
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    • v.15 no.4
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    • pp.178-186
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    • 1997
  • The purpose of this study is to evaluate the J-R curve characteristics for the 5083 aluminum alloy weldment by the load ratio analysis. The results of the load ratio analysis are compared with those of the J-R curve which are obtained by the ASTM unloading compliance method. The crack length calculated by the load ratio analysis is agrees well with the measured final crack length. The slope of the exponential J-R curve estimated by the load ratio analysis is slightly smaller than that by the ASTM unloading compliance method. The exponential correlation of the J-R curve for the 5083 aluminum alloy base metal by the load ratio analysis is J = 93.88 ${\Delta}{\alpha}^{0.375}$. That for the weld metal and HAZ is J = 69.87 ${\Delta}{\alpha}^{0.389}$ and J = 70.59 ${\Delta}{\alpha}^{0.359}$ respectively. The J-R curve obtained by the ASTM unloading compliance method is overpredicted and should be offsetted due to the initial negative crack. On the other hand, the load ratio analysis method can evaluate the J-R curve by only load displacement curve without particular crack measurement equipment.

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Validity Examination on Evaluation of J-R Curve in the Nuclear Reactor Pressure Vessel Steels and Aluminum Alloys by Load Ratio Analysis (원자로 압력용기강 및 Al 합금재의 J-R곡선평가시 Load Ratio 해석의 유효성 검토)

  • Yoon, H.K.;Woo, D.H.;Kim, Y.K.;Cha, G.J.
    • Journal of Power System Engineering
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    • v.1 no.1
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    • pp.80-90
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    • 1997
  • The purpose of this study is to evaluate the validity examination of the J-R curve characteristics for the nuclear reactor pressure vessel steels and Al alloys by the load ratio analysis. The results of the load ratio analysis are compared with those of the J-R curve which are obtained by the ASTM unloading compliance method. The crack length calculated by the load ratio analysis is agree well with the measured final crack length. The slope of the exponential J-R curve estimated by the load ratio analysis is slightly smaller than that by the ASTM unloading compliance method. The J-R curve obtained by the ASTM unloading compliance method is over-predicted and should be offsetted due to the initial negative crack. On the other hand, the load ratio analysis method can evaluate the J-R curve by only load-displacement curve without particular crack measurement equipment.

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Current status of foodservice nutrition management and effects of welfare facility support for the elderly in Cheongju City

  • Lee, Joo-Eun
    • Nutrition Research and Practice
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    • v.16 no.4
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    • pp.527-536
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    • 2022
  • BACKGROUND/OBJECTIVES: South Korea is representative of countries experiencing rapid societal aging. This study aimed to understand the current status of foodservice nutrition management provided to welfare facilities for the elderly and to understand improvements after support from "the Center for Social Welfare Foodservice Management (CSWFM)" in Cheongju City. SUBJECTS/METHODS: The status of foodservice nutrition management was assessed by dietitians and hired by the CSWFM, who visited 40 welfare facilities (registered members of the CSWFM) for the elderly in Cheongju City. After visiting each facility three times from July to December 2019, the results of inspections on four areas, that is, 'menu', 'meal provision', 'cooking', and 'distribution' management for 2nd and 3rd visits (support visits) were compared with results obtained at initial visits. RESULTS: Before support as determined during 1st visits, compliance rates with 'menu', 'meal provision', 'cooking', and 'distribution' requirements were 72.1%, 75.5%, 58.3%, and 77.5%, respectively. The mean compliance rate for all 15 items on the questionnaire used was 70.8%. Items with low compliance rates were 'Is the soup provided by foodservice at the recommended salinity?' (compliance rate 37.5%) and 'Is the foodservice cooking conducted by referring to a recipe?' (42.5%). At the two support visits, mean compliance rates increased significantly (P < 0.01, P < 0.001), mean total score had significantly increased from 71.80 to 90.26 (P < 0.001), and mean soup salinity decreased significantly from 0.82% at 1st visits to 0.68% (P < 0.001) and 0.56% (P < 0.001) at the 1st and second follow-up visits. CONCLUSIONS: These results show that the status of nutrition management at welfare facilities for the elderly was much improved by CSWFM involvement, and indicate the CSWFM should continuously provide nutrition management support to facilities and that finances and opportunities for more welfare facilities for the elderly be expanded.