• Title/Summary/Keyword: Reduction effects

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Evaluation of multi-lane transverse reduction factor under random vehicle load

  • Yang, Xiaoyan;Gong, Jinxin;Xu, Bohan;Zhu, Jichao
    • Computers and Concrete
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    • v.19 no.6
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    • pp.725-736
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    • 2017
  • This paper presents the two-, three-, and four-lane transverse reduction factor based on FEA method, probability theory, and the recently actual traffic flow data. A total of 72 composite girder bridges with various spans, number of lanes, loading mode, and bridge type are analyzed with time-varying static load FEA method by ANSYS, and the probability models of vehicle load effects at arbitrary-time point are developed. Based on these probability models, in accordance to the principle of the same exceeding probability, the multi-lane transverse reduction factor of these composite girder bridges and the relationship between the multi-lane transverse reduction factor and the span of bridge are determined. Finally, the multi-lane transverse reduction factor obtained is compared with those from AASHTO LRFD, BS5400, JTG D60 or Eurocode. The results show that the vehicle load effect at arbitrary-time point follows lognormal distribution. The two-, three-, and four-lane transverse reduction factors calculated by using FEA method and probability respectively range between 0.781 and 1.027, 0.616 and 0.795, 0.468 and 0.645. Furthermore, a correlation between the FEA and AASHTO LRFD, BS5400, JTG D60 or Eurocode transverse reduction factors is made for composite girder bridges. For the two-, three-, and four-lane bridge cases, the Eurocode code underestimated the FEA transverse reduction factors by 27%, 25% and 13%, respectively. This underestimation is more pronounced in short-span bridges. The AASHTO LRFD, BS5400 and JTG D60 codes overestimated the FEA transverse reduction factors. The FEA results highlight the importance of considering span length in determining the multi-lane transverse reduction factors when designing two-lane or more composite girder bridges. This paper will assist bridge engineers in quantifying the adjustment factors used in analyzing and designing multi-lane composite girder bridges.

Parasitic Effects due to Current Blocking Structure (전류차단층의 기생효과 해석)

  • 김동철;심종인;어영선;박문규;강중구;계용찬;장동훈
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.02a
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    • pp.148-149
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    • 2003
  • The parasitic effects due to the current blocking layer limit the bandwidth of the semiconductor laser diode. Thus, the parasitic response of various blocking layers was analyzed. The inin type was the best choice for the leakage current reduction and the bandwidth expansion.

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Design and Manufacturing Characteristics of Eco-Friendly Wood Street Lamp (친환경 목재가로등의 디자인 및 제조특성)

  • Kim, Jong-In;Jung, Su-Young;Won, Kyung-Rok
    • Journal of the Korea Furniture Society
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    • v.25 no.4
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    • pp.345-352
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    • 2014
  • This study was carried out to develop eco-friendly wood street lamp (EFWSL) by using wood resources stacked in the forests after tree tending operations which were mostly abandoned, but economical as renewable wood resources for developing the wood coated street lamps with the effects of cost reduction and their attractive appearances. This study has led to the development of key compact structures of street-lighting wood poles (shaft) using laminated timber. The core technique in this study is related with producing the more stable wood poles (shaft) with the hole inside than wood poles exposed under the natural environment through applicable process to protect the wood from bursting and splitting. We also comprehensively developed the method to conserve the timber durability of wood shaft and connect the wood shaft with groove, race way to be located in the groove, locking ring, current stabilizer connected to the groove and luminaire support arm, base and hand-hole which was partly used in combination with steel materials and wood. Also we increased the utilization of abandoned and stacked woods after thinning in the forests such as Pinus densiflora, Larix leptolepis, and Pinus koraiensis plantations by maximizing the value of these natural wood resources as main materials of eco-friendly street lightings with the effects of cost reduction and attractive appearances and also the expectation of advertising effects of street lightings developed in this study.

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Effect of Yagwan-cheunghyeoltang on Obesity in Rats Induced by High Fat Diet (야관청혈탕이 고지방식이로 유도된 흰쥐의 비만 억제에 미치는 영향)

  • Park, Sang-Woo;Cho, Chung-Sik;Kim, Chul-Jung
    • The Journal of Internal Korean Medicine
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    • v.32 no.2
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    • pp.170-187
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    • 2011
  • Background : Obesity, the syndrome caused by a high fat diet, is a disease. At the same time, obesity causes diabetes mellitus, hyperlipidemia, and cardiovascular disease. Recently, its prevalence rate is increasing. Yagwan-cheunghyeoltang (YCT) used in this experiment is the prescription of Yagwanmoon added to Cheunghyeol-tang which is reported to be very effective in weight loss controlling and serum cholesterol. It is also reported that Yagwanmoon has significant antioxidant effects and YCT has a significant effect on blood glucose control. Objectives : This study was conducted to experimentally evaluate the effects of YCT on obesity in rats induced by high fat diet. Methods : The experiment was conducted with 4-week-old male rat s divided into 5 groups. They were a normal diet group, a high fat diet group, a positive drug control group, a 1% YCT group, and a YCT 3% group, and were tested for eight weeks. After four weeks of inducing obesity by a high fat diet, rats were allowed to lose weight by following the normal diet group, approximately 30% compared with 10 rats in each group were determined as still obese. Changes in body weight and organ weight and serum cholesterol, triglyceride, glucose-density, low density lipoprotein cholesterol, antioxidant activity were checked. Results : In the experimental groups, we observed weight loss and visceral fat reduction, improvement of liver function, reduction of serum glucose, activation of HMG-CoA reductase inhibitor, reduction of concentrations of leptin and it showed a significant effect on antioxidants and lipid peroxidation. Conclusions : YCT has significant effects on the regulation of hyperlipidemia and lipid peroxidation associated with obesity and has significant effects on, antioxidants and lipid peroxidation, too. Additional clinical studies are needed.

The effects of drag reducing polymers on flow stability : Insights from the Taylor-Couette problem

  • Dutcher, Cari S.;Muller, Susan J.
    • Korea-Australia Rheology Journal
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    • v.21 no.4
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    • pp.213-223
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    • 2009
  • Taylor-Couette flow (i.e., flow between concentric, rotating cylinders) has long served as a paradigm for studies of hydrodynamic stability. For Newtonian fluids, the rich cascade of transitions from laminar, Couette flow to turbulent flow occurs through a set of well-characterized flow states (Taylor Vortex Flow, wavy Taylor vortices, modulated wavy vortices, etc.) that depend on the Reynolds numbers of both the inner and outer cylinders ($Re_i$ and $Re_o$). While extensive work has been done on (a) the effects of weak viscoelasticity on the first few transitions for $Re_o=0$ and (b) the effects of strong viscoelasticity in the limit of vanishing inertia ($Re_i$ and $Re_o$ both vanishing), the viscoelastic Taylor-Couette problem presents an enormous parameter space, much of which remains completely unexplored. Here we describe our recent experimental efforts to examine the effects of drag reducing polymers on the complete range of flow states observed in the Taylor-Couette problem. Of particular importance in the present work is 1) the rheological characterization of the test solutions via both shear and extensional (CaBER) rheometry, 2) the wide range of parameters examined, including $Re_i$, $Re_o$ and Elasticity number E1, and 3) the use of a consistent, conservative protocol for accessing flow states. We hope that by examining the stability changes for each flow state, we may gain insights into the importance of particular coherent structures in drag reduction, identify simple ways of screening new drag reducing additives, and improve our understanding of the mechanism of drag reduction.

The Effects of Stone Massage Therapy on Abdominal Obesity Reduction (스톤마사지 테라피가 복부비만의 감소에 미치는 영향)

  • Ban, So-Jeong;Kim, Jung-Sook;Kim, Ji-Hyeon
    • Journal of the Korea Fashion and Costume Design Association
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    • v.15 no.4
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    • pp.17-27
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    • 2013
  • This study has the purpose to examine the effects of stone massage therapy on abdominal obesity reduction. 10 sessions for 5 weeks two times a week of stone massage therapy were offered to 43 adult females who were 40s through 70s with 27% or more of body fat and the results were analyzed. The body composition like body fat mass, fat free mass, weight and skeletal muscular mass etc and the degrees of obesity like body fat ratio abdominal fat ratio were measured and analyzed before and after stone massage therapy. The results are as follows: First, the subjects were obese body type and stone massage therapy produced positive effects with body fat mass, fat free mass, weight and BMI value slightly less than before the therapy. Second, as the average values of body fat ratio and waist hip ratio of subject were significantly different statistically before and after the therapy, stone massage therapy was found to be effective in reducing abdominal obesity. Third, as for the change of waist hip ratio, the therapy was found to be effective in reducing waist hip ratio that 40s decreased insignificantly after the therapy, and 50s and 60s significantly at p<0.05 level respectively from 0.92 to 0.90 and from 0.93 to 0.92. In conclusion, the results of this study indicated that stone massage therapy has positive effects on abdominal obesity reduction, and can contribute to healthy life and well-being culture.

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Multifactor Dimensionality Reduction (MDR) Analysis to Detect Single Nucleotide Polymorphisms Associated with a Carcass Trait in a Hanwoo Population

  • Lee, Jea-Young;Kwon, Jae-Chul;Kim, Jong-Joo
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.6
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    • pp.784-788
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    • 2008
  • Studies to detect genes responsible for economic traits in farm animals have been performed using parametric linear models. A non-parametric, model-free approach using the 'expanded multifactor-dimensionality reduction (MDR) method' considering high dimensionalities of interaction effects between multiple single nucleotide polymorphisms (SNPs), was applied to identify interaction effects of SNPs responsible for carcass traits in a Hanwoo beef cattle population. Data were obtained from the Hanwoo Improvement Center, National Agricultural Cooperation Federation, Korea, and comprised 299 steers from 16 paternal half-sib proven sires that were delivered in Namwon or Daegwanryong livestock testing stations between spring of 2002 and fall of 2003. For each steer at approximately 722 days of age, the Longssimus dorsi muscle area (LMA) was measured after slaughter. Three functional SNPs (19_1, 18_4, 28_2) near the microsatellite marker ILSTS035 on BTA6, around which the QTL for meat quality were previously detected, were assessed. Application of the expanded MDR method revealed the best model with an interaction effect between the SNPs 19_1 and 28_2, while only one main effect of SNP19_1 was statistically significant for LMA (p<0.01) under a general linear mixed model. Our results suggest that the expanded MDR method better identifies interaction effects between multiple genes that are related to polygenic traits, and that the method is an alternative to the current model choices to find associations of multiple functional SNPs and/or their interaction effects with economic traits in livestock populations.

Effects of cranberry powder on biomarkers of oxidative stress and glucose control in db/db mice

  • Kim, Mi Joung;Chung, Jee-Young;Kim, Jung Hee;Kwak, Ho-Kyung
    • Nutrition Research and Practice
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    • v.7 no.6
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    • pp.430-438
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    • 2013
  • Increased oxidative stress in obese diabetes may have causal effects on diabetic complications, including dyslipidemia. Lipopolysccharides (LPS) along with an atherogenic diet have been found to increase oxidative stress and insulin resistance. Cranberry has been recognized as having beneficial effects on diseases related to oxidative stress. Therefore, we employed obese diabetic animals treated with an atherogenic diet and LPS, with the aim of examining the effects of cranberry powder (CP) on diabetic related metabolic conditions, including lipid profiles, serum insulin and glucose, and biomarkers of oxidative stress. Forty C57BL/KsJ-db/db mice were divided into the following five groups: normal diet + saline, atherogenic diet + saline, atherogenic diet + LPS, atherogenic diet + 5% CP + LPS, and atherogenic diet + 10% CP + LPS. Consumption of an atherogenic diet resulted in elevation of serum total cholesterol and atherogenic index (AI) and reduction of high density lipoprotein (HDL)-cholesterol. However, with 10% CP, the increase in mean HDL-cholesterol level was close to that of the group with a normal diet, whereas AI was maintained at a higher level than that of the group with a normal diet. LPS induced elevated serum insulin level was lowered by greater than 60% with CP (P < 0.05), and mean serum glucose level was reduced by approximately 19% with 5% CP (P > 0.05). Mean activity of liver cytosolic glutathione peroxidase was significantly increased by LPS injection, however it was reduced back to the value without LPS when the diet was fortified with 10% CP (P < 0.05). In groups with CP, a reduction in mean levels of serum protein carbonyl tended to occur in a dose dependent manner. Particularly with 10% CP, a reduction of approximately 89% was observed (P > 0.05). Overall results suggest that fortification of the atherogenic diet with CP may have potential health benefits for obese diabetes with high oxidative stress, by modulation of physical conditions, including some biomarkers of oxidative stress.

Evaluating Commercial Spray Applications of Lactic Acid, Hot Water, and Acidified Sodium Chlorite for the Reduction of Escherichia coli on Beef Carcasses

  • Kang, Dong-Hyun;Lee, Sun-Young
    • Food Quality and Culture
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    • v.2 no.1
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    • pp.55-60
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    • 2008
  • This study examined the effects of lactic acid spray, hot water spray, or their combined treatment, as well as the effects of acidified sodium chlorite (ASC), for the decontamination of Escherichia coli on beef carcass surfaces using a commercial intervention system. With this system, the effects of 2 or 4% lactic acid (v/v), hot water ($89{\pm}1^{\circ}C$), or their combined treatment, were examined in terms of reducing inoculated E. coli. ASC (266 ppm), which was adjusted to pH 2.5 using acetic acid or citric acid, was applied using a hand-held spray system. When the beef carcasses were treated with 2 or 4% lactic acid for 10.4 s, less than 1 log reductions of inoculated E. coli were observed. A hot water spray treatment for 9.8 s resulted in a 2.1 log reduction of inoculated E. coli. However, when the hot water was followed with either 2 or 4% lactic acid, no difference in E. coli reduction was found between the hot water alone or the combined treatment with lactic acid. When ASC was adjusted to pH 2.5 with acetic acid and citric acid, 3.8 and 4.1 log reductions of E. coli were observed, respectively. Overall, the lactic acid spray treatment was least effective, and the ASC treatment was most effective, for the E. coli decontamination of beef carcasses. Therefore, these data suggest that ASC would be a more effective intervention against E. coli than most of the methods currently being used. However, more research is required to evaluate the effects of ASC on other organisms, as well as to identify application methods that will not affect meat quality.

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