• 제목/요약/키워드: Reduced mechanism

검색결과 2,175건 처리시간 0.031초

db/db 마우스에서 수풍순기환의 혈당강하 활성 및 기전연구 (Blood Glucose Lowering Activity and Mechanism of Supungsungihyan (SPSGH) in db/db Mouse)

  • 이성현;안세영;두호경;정성현
    • Biomolecules & Therapeutics
    • /
    • 제7권4호
    • /
    • pp.335-341
    • /
    • 1999
  • Antidiabetic activity and mechanism of Supungsungihyan(SPSGH) were examined in db/db mice, which is a spontaneously hyperglycemic, hyperinsulinemic and obese animal model. SPSGH and acarbose were administered orally for 4 weeks. Fasting and non-fasting serum glucose, glycated hemoglobin and trig-lyceride of SPSGH treated group were all reduced when compared with those of db/db control group. At 12th week after birth, SPSGH increased an insulin secretion although statistic significance was not seen. Total activities of sucrose, maltase and lactase in SPSGH treated group were not significantly different from those in db/db control. On the other hand, sucrase and maltase activities in acarbose treated groups were increased. Effect of SPSGH on mRNA expression of glucose transporter(GLUT-4) was also examined by RT-PCR and in vitro transcription with co-amplification of rat $\beta$-actin gene as an internal standard. Muscular GLUT-4 mRNA expression in SPSGH treated group was increased significantly. These results may suggest that SPSGH lowered blood glucose ascribing to upregulation of muscular GLUT-4 mRNA expression.

  • PDF

RCAR 전방 저속 충돌시험 대응 범퍼 스테이 설계 (Bumper Stay Design for RCAR Front Low Speed Impact Test)

  • 강성종
    • 한국자동차공학회논문집
    • /
    • 제24권2호
    • /
    • pp.191-197
    • /
    • 2016
  • RCAR low speed impact test estimates repair cost of the impacted vehicle. In this study, for a mid-size vehicle front body model, structural performance for RCAR low speed impact were analyzed with changing the bumper stay shape and size. First, for improving the impact load transfer mechanism to side member the stay rear section shape at connecting area with side member was modified and the stay outer was redesigned to be normal to the barrier. Next, the investigation on stay thickness effect was carried out and the performances of several models with different forming shape were compared. The final design showed 13mm decrease in the maximum barrier intrusion distance and greatly reduced side member deformation. Additional analyses explained the validity of the final design.

PKINIT기반의 향상된 Kerberos 인증에 관한 연구 (A study on advanced Kerberos Authentication between Realms based on PKINIT)

  • 신광철;정진욱
    • 한국컴퓨터산업학회논문지
    • /
    • 제2권12호
    • /
    • pp.1541-1548
    • /
    • 2001
  • 본 논문에서는 IETF CAT Working Group에서 발표한 PKINIT 기반의 인증서비스를 향상시킨 Kerberos 인증 메커니즘을 제안한다. 서비스를 위한 상호 영역간 인증은 X.509와 DS/DNS를 이용하는 PKINIT를 통한 체인에 의해서 연결하였다. 영역간 서비스를 위해 공통키와 공개키를 사용하며 실제적인 인증은 Kerberos의 공통키에 두고 PKINIT의 X.509는 공개키를 이용하여 세션을 설정하였다. 새로운 메커니즘은 원격영역에서 티켓을 얻기 위하여 KDC의 인증서 사용으로 Client와 원격 KDC간 인증절차를 간소화시킴으로써 통신부담을 줄이고 원격 KDC의 재확인 과정이 생략되었다.

  • PDF

암성 악액질의 최신 지견 (Recent Advances in Cancer Cachexia)

  • 최상규
    • 종양간호연구
    • /
    • 제11권1호
    • /
    • pp.20-25
    • /
    • 2011
  • Purpose: The study was aimed to review and understand the meaning of cancer cachexia. Methods: Using the keywords "cachexia" and "cancer cachexia" 30 oncology research published from 1974 to 2009 were selected for the review. Results: The mechanism of cancer cachexia has not been fully understood, but various pathogenesis appears to be involved in the development cachexia including altered metabolism of carbohydrate, lipid, and protein associated with cytokines and hormone. As a result, muscle strength, food intake and resting energy expenditure (REE) are reduced. Most medications for the treatment of cachexia show debating results except some drugs such as megace. Supportive care including nutritional education, nursing care, and social support are found another effective treatment options. Conclusion: The results of this study would help oncology nurses to understand the mechanism of cancer cachexia and its management.

최소 이송 기구를 갖는 PC-NC 기반의 비구면 렌즈 연마 장치에 관한 연구 (A Study on PC-NC Based Aspherical Lens Polishing System with Minimum Translation Mechanism)

  • 양민양;이호철
    • 한국정밀공학회지
    • /
    • 제18권7호
    • /
    • pp.65-71
    • /
    • 2001
  • The development process of the polishing system for the aspherical lens mold for opto-electronics industry is described. The system uses the method that polishing tool is scanned on the surface under PC-NC control for the aspherical lens mold. The two axes interpolation of the minimum translation mechanism is applied to give uniform working condition by motion analysis. An aspherical surface is divided into multiple sections and each dwell time is calculated from the polishing rate model based on the Preston equation. As result of form error compensation experiment, initial form error is decreased about 25% while an average value of surface roughness is also reduced successfully from 180nm to 19nm.

  • PDF

Decentralized Supply Chain Coordination with Revenue Sharing Mechanism: Transfer Pricing Heuristics and Revenue Share Rates

  • Chen, Hung-Yi;Wu, Hsiao-Chung
    • Industrial Engineering and Management Systems
    • /
    • 제8권4호
    • /
    • pp.213-220
    • /
    • 2009
  • A revenue sharing contract is one of the mechanisms that coordinate decision makers in a decentralized supply chain toward the consensual goal. The transfer prices between different echelons in the supply chain influence the total supply chain profits. The study aims to explore various transfer pricing heuristics on the supply chain coordination in terms of the supply chain profits and their interactions with the revenue sharing rate. A model is proposed for formulating the collaborative production and distribution planning in a decentralized supply chain with the revenue sharing mechanism. Experiment results indicate that the transfer price and the revenue sharing rate affect significantly the coordination. Among the studied pricing heuristics, the variable-cost pricing method led to the best SC profits. Raising the revenue sharing rate reduced the SC profits no matter what heuristics were employed. Furthermore, the experiments provide us clues for finding the optimal transfer price for the supply chain.

왕복동형 압축기 볼 조인트 접촉의 탄성유체윤활 해석 (EHL Analysis of the Ball Joint Contact in a Reciprocating Compressor)

  • 김태종
    • Tribology and Lubricants
    • /
    • 제19권2호
    • /
    • pp.85-93
    • /
    • 2003
  • In this study, a multigrid multi-integration method has been used to solve the steady-state, elastohydrodynamic lubrication (EHL) point contact problem of a ball joint mechanism used in small reciprocating compressors. Pressure and film thickness profiles have been calculated at minimum and maximum Moes M parameter conditions during one revolution of crankshaft. The effects of various lubricant viscosities, loads, ball velocities, elastic modulli, and radii of curvature on the calculated pressure distribution and film thicknesses have been investigated. The results indicate that the viscosity of lubricant, the sliding velocity of ball, and the reduced radius of curvature have considerable effects on the minimum and central film thicknesses. Solutions obtained with the multigrid analysis are compared with results calculated according to the Hamrock & Dowson relations for the minimum and central film thicknesses.

Antidiabetic Activity and Mechanisms of Acarbose in $KKA^{y}$ Mice

  • Kim, Young-Lim;Chung, Sung-Hyun
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제5권2호
    • /
    • pp.183-188
    • /
    • 2001
  • To elucidate antidiabetic effect and mechanism(s) of acarbose in a polygenic spontaneous hyperglycemic and hyperinsulinemic diabetic animal model, $KKA^y$ mice, acarbose was administered orally for 4 weeks and effects on body weight, plasma glucose and insulin levels, genetic expressions of intestinal sucrase-isomaltase (SI), sodium-glucose cotransporter (sGLT1) and glucose transporter in quadriceps muscle (GLUT4) were examined in this study. Although no differences in body weight were detected between control and acarbose-treated groups, plasma glucose level in acarbose-treated group was markedly reduced as compared to the control. In the mechanism study, acarbose downregulated the SI and SGLT1 gene expressions, and upregulated the GLUT4 mRNA and protein expressions when compared to the control group. In conclusion, the data obtained strongly implicate that acarbose can prevent the hyperglycemia in $KKA^y$ mice possibly through blocking intestinal glucose absorption by downregulations of SI and sGLT1 mRNA expressions, and upregulation of skeletal muscle GLUT4 mRNA and protein expressions.

  • PDF

$SiC_t/Si_3N_4$ 세라믹 복합재료의 크리프 거동 및 파손 메카니즘에 관한 연구 (A Study on the Creep Behavior and Failure Mechanism of the $SiC_t/Si_3N_4$ Ceramic Composite)

  • 박용환
    • 한국안전학회지
    • /
    • 제13권4호
    • /
    • pp.131-136
    • /
    • 1998
  • The creep behavior and failure mechanism of the 30 vol% hot-pressed $SiC_t/Si_3N_4$ ceramic composite was experimentally investigated at $1200^{\circ}C$ and at various stress levels in air. The creep threshold stress for zero creep rate after 100 hr was found to be approximately 60 MPa. The stress exponent was estimated to be n~1, which suggests that fiber-reinforcement reduced the stress sensitivity of the HPSN matrix with the stress exponent of 2. The tertiary stage leading to creep rupture was found at 250 MPa but was very short. The microstructure of the crept specimen showed random fiber fracture and no matrix cracking. Interfacial debonding was absent.

  • PDF

광디스크 드라이브의 고속 액세스를 위한 광픽업 액추에이터 메커니즘 설계 (Mechanism Design of Optical Pickup Actuator for Fast Access of Optical Disk Drive)

  • 박준혁;이상헌;백윤수
    • 한국정밀공학회지
    • /
    • 제19권12호
    • /
    • pp.109-119
    • /
    • 2002
  • In this paper, mechanism design of optical pickup actuator for fast access is proposed. This actuator is composed of moving magnet type actuator and moving coil type actuator for tracking and fine motion, respectively. Moving magnet type tracking actuator is configurated by two permanent magnets and four air-core solenoids. Additional damper by induced current in tracking actuator can reduce the transient vibration between the coarse seeking servo and fine seeking servo. Variable stiffness can be acquired by applying current to air-core solenoid simply. This actuator can achieve fast access by these additional damper and stiffness. Performance of this actuator is predicted through the FEM, simulation and simple experiment. Settling time for transient vibration is reduced to 14.7% according to simulation result.