• Title/Summary/Keyword: effect modification

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Modification of Discharge Mechanism of Binder Harvesters (바인더수확기(收穫期)의 방출구조(放出構造) 개선(改善)에 관한 연구(硏究))

  • Park, Keum Joo;Chung, Chang Joo;Ryu, Kwan Hee
    • Journal of Biosystems Engineering
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    • v.8 no.2
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    • pp.26-38
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    • 1983
  • Binder harvesters introduced to Korea were originally designed to be used for Japonica varieties which are highly resistant to shattering. In order to improve the performance of the binder to Indica varieties which are easily shattered and have shorter stem, mechanical modifications of the binder are inevitable. Shattering losses of the binder can be classified into two major parts; one incurred before and one after binding operations. The latter has been evaluated as great as the former. Previous studies indicated that the high discharge losses resulted from a great impact force of the discharge arm on the rice bundle during the discharge process. This study was intended to theoretically analyze the discharge mechanism of four-bar linkage. For this purpose, two commercially available binder harvesters having a four-bar linkage as a discharge mechanism were analyzed. Using the results from the motion analysis and the other structural constraints of the machines, they were modified and experimentally compared with the machines without modification to see whether any decrease in grain losses was obtained. The results obtained in this study are summarized as follows: 1. The path, velocity and acceleration of discharge arm were computer analyzed by vector analysis. Using results of the analysis and intrinsic constraints of the binder, discharge mechanism was modified to reduce the impact force on bundle by discharge arm in the range where the discharge performance was not deteriorated. This modification of the discharge mechanism could be done with an aid of four-bar linkage synthesis technique. As a result, average velocity and acceleration of the discharge arm during the discharge process were reduced respectively by 19 percent and 33 percent for binder A, and 17 percent and 35 percent for binder B. 2. Through the modification of the discharge mechanism, discharge losses of binder A were reduced by 42-56 percent for Milyang 23, Poongsan and Hangang chal, and discharge losses of binder B were reduced by 13-20 percent for Milyang 23 and Poongsan. 3. Discharge losses were decreased as the bundle size became larger and the size effect on the decrease rate appeared more significant in the binders with modifications than in those without modifications.

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The Effects of Exercise Therapy and Exercise-Behavior Modification Therapy on Obesity, Blood Lipids, and Self-esteem of the Obese Middle-aged Women (운동요법, 운동.행동수정요법이 중년 비만여성의 비만도, 혈중지질 및 자아존중감에 미치는 효과)

  • 김인홍
    • Journal of Korean Academy of Nursing
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    • v.32 no.6
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    • pp.844-854
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    • 2002
  • To examine the effect of the exercise therapy, and exercise-behavior modifi- cation therapy on obesity, blood lipids and self-esteem of the obese middle-aged women. Method: A total of 35 middle-aged women (BMI: over 30) were selected for this research. Walking at a 50% intensity was administered 4 days a week for 12 weeks, while the behavior modification therapy performed for 60~90 minutes per week for 12 weeks. Result: Body weight and BMI has significantly reduced in the case of EG and E BG. The result of comparing body weight between groups showed significant difference between EG and CG, and E BG and CG whereas BMI showed significant difference between EG and CG only. TC, TG, LDL-C, %TC/HDL-C have shown significant decrease in EG and E-BG, while HDL-C displayed significant increase in EG and E BG. And HDL-C showed significant decrease in CG. As for comparison between groups, significant difference was noted in EG and CG, and E BG and CG at TC, HDL-C, LDL-C, and in EG and CG at %TC/HDL-C. Self-esteem displayed significant increase in EG and E BG; however, there was no significant different in CG. As for comparison between groups, there was significant difference noted in E BG and CG only. Conclusion: The results showed that the exercise therapy and the exercise-behavior modification therapy were effective in changing obesity, blood lipids and self-esteem of the obese middle-aged women.

Anti-calcification of Bovine Pericardium for Bioprosthetic Heart Valves after Surface Modification with Hyaluronic Acid Derivatives

  • Hahn Sei Kwang;Ohri Rachit;Giachelli Cecilia M.
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.3
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    • pp.218-224
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    • 2005
  • Surface modification of glutaraldehyde fixed bovine pericardium (GFBP) was success­fully carried out with hyaluronic acid (HA) derivatives. At first, HA was chemically modified with adipic dihydrazide (ADH) to introduce hydrazide functional group into the carboxyl group of HA backbone. Then, GFBP was surface modified by grafting HA-ADH to the free aldehyde groups on the tissue and the subsequent HA-ADH hydrogel coating. HA-ADH hydrogels could be prepared through selective crosslinking at low pH between hydrazide groups of HA-ADH and crosslinkers containing succinimmidyl moieties with minimized protein denaturation. When HA­ADH hydrogels were prepared at low pH of 4.8 in the presence of erythropoietin (EPO) as a model protein, EPO release was continued up to $85\%$ of total amount of loaded EPO for 4 days. To the contrary, only $30\%$ of EPO was released from HA-ADH hydrogels prepared at pH=7.4, which might be due to the denaturation of EPO during the crosslinking reaction. Because the carboxyl groups on the glucuronic acid residues are recognition sites for HA degradation by hyaluronidase, the HA-ADH hydrogels degraded more slowly than HA hydrogels prepared by the crosslinking reaction of divinyl sulfone with hydroxyl groups of HA. Following a two-week subcutaneous implantation in osteopontin-null mice, clinically significant levels of calcification were observed for the positive controls without any surface modification. However, the calcification of surface modified GFBP with HA-ADH and HA-ADH hydrogels was drastically reduced by more than $85\%$ of the positive controls. The anti-calcification effect of HA surface modification was also confirmed by microscopic analysis of explanted tissue after staining with Alizarin Red S for calcium, which followed the trend as observed with calcium quantification.

Surface Treatment Effect on Electrochemical characteristics of Al Alloy for ship

  • Lee, Seung-Jun;Kim, Seong-Jong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2017.05a
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    • pp.149-149
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    • 2017
  • Aluminum alloys have poor corrosion resistance compared to the pure aluminum due to the additive elements. Thus, anodizing technology artificially generating thick oxide films are widely applied nowadays in order to improve corrosion resistance. Anodizing is one of the surface modification techniques, which is commercially applicable to a large surface at a low price. However, most studies up to now have focused on its commercialization with hardly any research on the assessment and improvement of the physical characteristics of the anodized films. Therefore, this study aims to select the optimum temperature of sulfuric electrolyte to perform excellent corrosion resistance in the harsh marine environment through electrochemical experiment in the seawater upon generating porous films by variating the temperatures of sulfuric electrolyte. To fabricate uniform porous film of 5083 aluminum alloy, we conducted electro-polishing under the 25 V at $5^{\circ}C$ condition for three minutes using mixed solution of ethanol (95 %) and perchloric (70 %) acid with volume ratio of 4:1. Afterward, the first step surface modification was performed using sulfuric acid as an electrolyte where the electrolyte concentration was maintained at 10 vol.% by using a jacketed beaker. For anode, 5083 aluminum alloy with thickness of 5 mm and size of $2cm{\times}2cm$ was used, while platinum electrode was used for cathode. The distance between the two was maintained at 3 cm. Anodic polarization test was performed at scan rate of 2 mV/s up to +3.0 V vs open circuit potential in natural seawater. Surface morphology was compared using 3D analysis microscope to observe the damage behavior. As a result, the case of surface modification showed a significantly lower corrosion current density than that without modification, indicating excellent corrosion resistance.

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Identifying psychological predictors of adherence to a community-based lifestyle modification program for weight loss among Chinese overweight and obese adults

  • Leung, Alice Wai Yi;Chan, Ruth Suk Mei;Sea, Mandy Man Mei;Woo, Jean
    • Nutrition Research and Practice
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    • v.13 no.5
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    • pp.415-424
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    • 2019
  • BACKGROUND/OBJECTIVES: Existing evidence on lifestyle modification programs for weight loss is limited by the high attrition rate of such programs. Identifying predictors of adherence to a lifestyle modification program could result in program improvement. However, little is known about behavior-specific adherence and its psychological predictors. This study aimed to examine the psychological predictors of adherence after one-month participation in a community-based lifestyle modification program among Chinese overweight and obese adults in Hong Kong. SUBJECTS/METHODS: A total of 205 Chinese overweight and obese adults aged $38.9{\pm}10.5years$ completed the study. Data were collected at baseline and after one month using self-reported questionnaires, which assessed knowledge (self-developed scale), motivation (Treatment Self-Regulation Questionnaire), stage of change (Stage of Exercise Scale) and self-efficacy (Self-Rated Abilities for Health Practices Scale). At one month, a 4-day dietary recall and the International Physical Activity Questionnaire-Short Form were used to assess dietary and physical activity (PA) adherence. Food and PA diaries were examined to indicate self-monitoring. Program attendance was tracked between baseline and one-month follow-up. RESULTS: After one month, participants reported high dietary adherence, attendance, and adherence to self-monitoring but low PA adherence. Multiple regression analyses suggested that diet self-efficacy (baseline) and nutrition knowledge (one-month change) were independent predictors of dietary adherence score at one month, whereas autonomous PA motivation (baseline) and PA self-efficacy (both baseline and one-month change) were independent predictors of PA adherence score at one month. No significant psychological predictor was identified for attendance or self-monitoring. CONCLUSIONS: The results suggest that the effect of psychological factors on adherence differs between diet and PA adherence outcomes. To promote adherence, practitioners should assess self-efficacy, knowledge, and motivation at the beginning of a weight-loss program and explore behavior-specific strategies to improve knowledge and self-efficacy. The results of this study have direct implications for program improvements.