• 제목/요약/키워드: stress reduction

검색결과 2,204건 처리시간 0.035초

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
    • /
    • 제7권6호
    • /
    • pp.430-438
    • /
    • 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.

끝단형상에 따른 복합소재 단일겹치기 체결부의 응력집중 저감에 관한 연구 (End-Shape Effect for Stress Concentration Reduction of Composite Single-Lap Bonded Joint)

  • 김정석;황재연
    • 대한기계학회논문집A
    • /
    • 제35권3호
    • /
    • pp.333-340
    • /
    • 2011
  • 본 연구에서는 복합소재 단일겹치기 조인트의 접착부재 형상 및 필렛 유무에 따른 응력집중 완화 효과를 평가하였다. 이를 위해 6가지 서로 다른 끝단부 형상에 대해 비선형 유한요소 해석을 수행하였다. 또한, 복합재 접착부재와 접착제의 다양한 강성비에 따른 6가지 모델의 최대 전단 및 수직응력의 변화를 고찰하였다. 접착부재가 순방향 테이퍼를 갖는 모델의 경우에는 가장 높은 응력값을 보여 조인트의 접합강도가 가장 취약할 것으로 예상되었다. 이에 반해, 접착부재가 역방향 테이퍼를 갖고 필렛이 존재할 경우 가장 낮은 응력값을 보였다. 접착부재와 접착제의 강성변화에 따른 최대응력 변화를 고찰한 결과 접착부재의 강성은 클수록, 접착제 강성은 낮을수록 응력집중은 완화되었다.

디지털-피지컬 구조를 이용한 신체 항상성 유지 공간 연구 (A Study on Usage of Integrated Digital-Physical Structure on Physical Homeostasis Space for Stress Reduction)

  • 강민수
    • 한국멀티미디어학회논문지
    • /
    • 제23권4호
    • /
    • pp.574-580
    • /
    • 2020
  • Stress induces change to the body functions and causes chronic problems such as worsening a disease. Thus, humans want to evade anxiety and would try any means to reduce stressful situations. Generally, a person would handle their stress by either regulating their emotions or merely coping with the situation, for which the former is most widely used. Our research aims to effectively reduce stress by using the emotional response structure developed by Plutichik and the vitalization method. We extracted the relevant components of the stress-reduction method that would be applicable in any space using digital technologies such as sensors, IoT, and augmented reality. An architect or designer may incorporate these structural components into any structure to effectively reduce people's stress. The research aims to provide a new perspective of architectural space and to show applications of the stress-reducing architectural spaces, which should also fulfill the people's needs. Further research is needed to develop an automatic system to utilize spatial components more effectively.

선체구조용강의 용접방법에 따른 용접부의 피로균열전파특성 연구 (A Study on the Fatigue Crack Growth Characteristics of the Welded Part According to the Welding Method of Ship Structural Steel)

  • 박경동;기우태;이주영
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제31권4호
    • /
    • pp.385-393
    • /
    • 2007
  • The strength evaluation of the most weakest junction part is required for the safety design of all structures. Most of all. in order to enhance the reliability and safety of the welding part. whose use is the highest, it is very important to establish the efficient structure manufacturing technology by studying and investigating the evaluation of fatigue strength in various environments. This study analyzed the relations of da/dN, and th according to the welding methods of SMAW, FCAW, and SAW. In the stage II. the value of stress intensity factor range was the highest in SMAW welding method of stress ration R=0.1, and appeared under the sequence of FCAW and SAW and as the completion section of stress intensity factor was low, threshold stress intensity factor was lowly formed in da/dN - The fatigue life of each welding method is sensitively worked in high stress ratio. judging from the fact that the width of life reduction increases in the high stress ratio zone compared to the width of life reduction in the low stress ratio zone. In the fatigue limit of welding methods before corrosion. the welding of SMAW and FCAW shows the same fatigue limit compared to Base metal, and SAW holds the lowest fatigue limit value.

미끄러지는 벨트 장치를 이용한 난류 항력 감소 (Turbulent Drag Reduction Using the Sliding-Belt Device)

  • 최병귀;최해천
    • 대한기계학회논문집B
    • /
    • 제23권11호
    • /
    • pp.1481-1489
    • /
    • 1999
  • The sliding-belt concept introduced by Bechert et al. (AIAA J., Vol. 34, pp. 1072~1074) is numerically applied to a turbulent boundary layer flow for the skin-friction reduction. The sliding belt is moved by the shear force exerted on the exposed surface of the belt without other dynamic energy input. The boundary condition at the sliding belt is developed from the force balance. Direct numerical simulations are performed for a few cases of belt configuration. In the ideal case where the mechanical losses associated with the belt can be ignored, the belt velocity increases until the integration of the shear stress over the belt surface becomes zero, resulting in zero skin friction on the belt. From practical consideration of losses occurred In the belt device, a few different belt velocities are given to the sliding belt. It is found that the amount of drag reduction is proportional to the belt velocity.

선박용 갑판크레인의 지브의 경량화설계 (Weight Reduction Design for a JIB of Deck Crane for Shipment)

  • 한동섭;이문재;한근조
    • 대한기계학회논문집A
    • /
    • 제33권4호
    • /
    • pp.396-400
    • /
    • 2009
  • The demand of JIB crane to handle a container or a bulk in a vessel is increasingly because of the growth of the scale of trade through the sea. This deck crane such as JIB crane is required the weight reduction design because it is installed in the deck of a vessel due to the environment regulation. In this study first we carry out the structural analysis of JIB with respect to the luffing angle of it to calculate the maximum equivalent stress of JIB, and next the optimum design for the weight reduction design of JIB. The thickness in a cross section of JIB is adopted as the design variable, the weight of JIB as the objective function, and the von mises stress as the constraint condition for the optimum design of JIB using the ANSYS 10.0.

부가증착을 이용한 마이크로 구멍의 크기감소 (Size reduction of micro-aperture using additional deposition)

  • 이준석;김규만
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2006년도 춘계학술대회 논문집
    • /
    • pp.505-506
    • /
    • 2006
  • Size reduction of micro-aperture using additional deposition is presented in this study. PECVD process was used for additional deposition. Rate of deposition is different with deposition direction because corners of shadowmask membrane have a taper. Deposition into backside showed better than deposition into frontside with size reduction. Shadowmask membrane with two materials has stress because of the difference of a coefficient of thermal expansion The cantilever of membrane bend to opposite direction of deposition. Deposition to both frontside and backside could reduce inside stress.

  • PDF

Output Inductor Less Phase Shift Full Bridge Converter with Current Stress Reduction Technique for Server Power Application

  • Lee, Woo-Jin;Park, Ki-Bum;Heo, Tae-Won;Moon, Gun-Woo
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2008년도 하계학술대회 논문집
    • /
    • pp.502-504
    • /
    • 2008
  • A new output inductor less phase shift full bridge converter with current reduction technique for server power application is proposed in this paper. The proposed converter can reduce the current stress by using the auxiliary circuit. Since the auxiliary circuit causes the additional resonance between the leakage inductor and auxiliary capacitor before the powering period, the proposed converter has lower current stress even no output filter inductor. Small size and circulating energy can be also the merits of the proposed converter. The operational principles and analysis are presented. Experimental results demonstrate that the current stress can be reduced effectively by using the auxiliary circuit without large output filter inductor.

  • PDF

족근관절 내과에 발생한 피로골절(1예보고) (Stress Fracture in Medial Malleolus in Ankle (A Case Report))

  • 이경태;양기원;박신이;이영구;나상은
    • 대한족부족관절학회지
    • /
    • 제12권2호
    • /
    • pp.224-226
    • /
    • 2008
  • Although stress fracture of lower extremity is a relatively common, stress fracture of medial malleolus is rare. So we report one case. He is a 17 year old soccer player and successfully treated with surgical treatment (open reduction and internal fixation with one screw.

  • PDF

구조물 보강용 탄소섬유쉬트의 부착특성에 관한 연구 (A Study on the Bond Properties of Carbon Fiber Sheets used for Strengthening Structures)

  • 황진석;김지영;백명종;박형철;박칠림
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
    • /
    • pp.653-658
    • /
    • 1997
  • Recently, carbon Fiber sheet (CFS) is frequently used for strengthening deteriorated concrete structures. To strengthening damaged structures, the property and characteristic of the bond between CFS and the concrete surface must be understood. The tensile test of single lap shear specimen was performed to study bond strength, bond stress distribution and stress transfer between CFS and concrete surface according to the bond length. Based on the test results, there were ultimate influence length (UIL) in which bond stress was distributed, and ultimate strain reduction ratio (USRR) by which strain was reduced linearly. Bond resisting force (BRF) was estimated by UIL and USRR, and which was compared with ultimate loads. According to the results of comparison, it was shown that ultimate bond strength could be estimated reasonablely by BRF.

  • PDF