• 제목/요약/키워드: size-dependent

검색결과 2,001건 처리시간 0.024초

Numerical analysis for behavior of outer concrete tank in emergency LNG spillage

  • Lee, Jeong Su;Park, Chan Kyu;Lee, Yun;Kim, Ji-Hoon;Kwon, Seung Hee
    • Computers and Concrete
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    • 제14권4호
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    • pp.369-385
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    • 2014
  • In the existing method for analyzing the liquid tightness of the outer concrete tank in an emergency LNG spillage, the temperature variation over time inside the tank, and the concrete properties dependent on temperature and internal moisture content, have not been taken into account. In this study, the analyses for a typical LNG concrete tank subjected to thermal load due to spillage were performed with three different cases: the existing method was adopted in the first case, the transient temperature variation was considered in the second, and the temperature-moisture content dependent concrete properties were taken into account as well as the transient states of temperature in the third. The analysis results for deformation, compressive zone size, cracking, and stress of reinforcements were compared, and a discussion on the difference between the results obtained from the different analysis cases was made.

Comparative Genomic Analysis of Food-Originated Coagulase-Negative Staphylococcus: Analysis of Conserved Core Genes and Diversity of the Pan-Genome

  • Heo, Sojeong;Lee, Jung-Sug;Lee, Jong-Hoon;Jeong, Do-Won
    • Journal of Microbiology and Biotechnology
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    • 제30권3호
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    • pp.341-351
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    • 2020
  • To shed light on the genetic differences among food-originated coagulase-negative Staphylococcus (CNS), we performed pan-genome analysis of five species: Staphylococcus carnosus (two strains), Staphylococcus equorum (two strains), Staphylococcus succinus (three strains), Staphylococcus xylosus (two strains), and Staphylococcus saprophyticus (one strain). The pan-genome size increases with each new strain and currently holds about 4,500 genes from 10 genomes. Specific genes were shown to be strain dependent but not species dependent. Most specific genes were of unknown function or encoded restriction-modification enzymes, transposases, or prophages. Our results indicate that unique genes have been acquired or lost by convergent evolution within individual strains.

Collective Electronic Oscillator Method: Application to Conjugated Organic Molecules

  • Lee, Jin-Yong
    • Bulletin of the Korean Chemical Society
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    • 제24권6호
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    • pp.780-784
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    • 2003
  • The collective electronic oscillator (CEO) method was developed by Mukamel and collaborators.[Phys. Rev. Lett. 1992, 69, 65; Science 1997, 277, 781] Recently Ⅰ have extended the CEO method to obtain the frequency dependent optical properties with all the contributing components. The brief introduction of the CEO fomalism and its recent applications to linear absorption and two-photon absorption (TPA) of conjugated organic molecules will be discussed. The size scaling of optical properties of polyenes and polyynes have studied by ab initio calculations, and this result is consistent with the coherence length of the time dependent densities to first ($ρ^(1)$) and second order ($ρ^(2)$) in the electric field obtained from the CEO method.

반복 하중을 받는 구조용재료의 파단전누설 ( LBB ) 조건에 관한 연구 ( Study on the LBB Conditions of Structure Material under Cyclic Load )

  • 남기우;코토지안도
    • 수산해양기술연구
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    • 제26권4호
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    • pp.380-386
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    • 1990
  • The high stress, low cycle fatigue test were carried out on HT80 plates with artificial part-through notch. The LBB conditions by the net section stress approach was examined in detail. Finite element methods for the state of deformation were also applied and the results were compared with the results from experiments. From the test results, it was noted that the LBB condition in fatigue test was dependent upon the maximun load change before and after the crack penetration. The LBB criterion By the net section stress approach were slightly dependent on initial crack size. It was shown that the state of deformation can be used to predict whether the component is likely to show LBB condition or they will be broken rapidly.

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Morphological Changes in Adipose and Liver Tissues by 17$\beta$-estradiol in Female Ovariectomized C57BL/6J Mice

  • Jeong, Sun-Hyo;Choi, Hyung-Kyu;Yoon, Mi-Chung
    • 대한의생명과학회지
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    • 제13권2호
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    • pp.99-104
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    • 2007
  • To determine whether 17$\beta$-estradiol induces the morphological changes in adipose and liver tissues, we measured the effects of 17$\beta$-estradiol on adipose tissue mass, adipocyte histology and hepatic lipid accumulation in female ovariectomized (OVX) C57BL/6J mice. Compared to vehicle-treated control mice, 17$\beta$-estradiol-treated mice decreased adipose tissue mass and the size of adipocytes, and concomitantly increased the number of adipocytes in a dose-dependent manner. In addition, the administration of 17$\beta$-estradiol resulted in reduced hepatic lipid accumulation in a dose-dependent manner. These results suggest that estrogen may regulate adipocyte development and lipid metabolism in female OVX C57BL/6J mice.

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Cell Cycle and Cancer

  • Park, Moon-Taek;Lee, Su-Jae
    • BMB Reports
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    • 제36권1호
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    • pp.60-65
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    • 2003
  • Cancer is frequently considered to be a disease of the cell cycle. As such, it is not surprising that the deregulation of the cell cycle is one of the most frequent alterations during tumor development. Cell cycle progression is a highly-ordered and tightly-regulated process that involves multiple checkpoints that assess extracellular growth signals, cell size, and DNA integrity. Cyclin-dependent kinases (CDKs) and their cyclin partners are positive regulators of accelerators that induce cell cycle progression; whereas, cyclin-dependent kinase inhibitors (CKIs) that act as brakes to stop cell cycle progression in response to regulatory signals are important negative regulators. Cancer originates from the abnormal expression of activation of positive regulators and functional suppression of negative regulators. Therefore, understanding the molecular mechanisms of the deregulation of cell cycle progression in cancer can provide important insights into how normal cells become tumorigenic, as well as how cancer treatment strategies can be designed.

전기유동유체를 이용한 브레이크 시스템의 성능 고찰 (Performance Investigation of a Brake System Featuring Electro-Rheological Fluids)

  • Kim, G.W.;Park, W.C.;Cheong, C.C.
    • 한국정밀공학회지
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    • 제12권7호
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    • pp.123-130
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    • 1995
  • This study presents model synthesis and performance investigation of a new brake system using electro-rheological(ER) fluids. Field-dependent Bingham properties characterized by non-zero yield stresses of the ER fluids are experimentally distilled. These properties are then incorporated with the governing equation of the proposed brake system which features design simplicity, fast response and salient controllability. After analyzing system performance with respect to design parameters such as electrode gap and length, an appropriate size of the brake is designed and fabricated. Both simulation and experimental works are undertaken in order to determine the feasibility and efficiency of the proposed brake system. The system performances are justified by evaluating field-dependent braking torques as well as braking times.

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압착모드하에서 ER유체의 빙햄특성 및 댐핑력 제어 (Bingham Properties and Damping Force Control of an ER Fluid under Squeeze Mode)

  • 홍성룡;최승복
    • 한국정밀공학회지
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    • 제19권11호
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    • pp.37-45
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    • 2002
  • This paper presents the field-dependent Bingham characteristics and damping force control of an electro-rheological (ER) fluid under squeeze mode operation. The squeeze force of the ER fluid due to the imposed electric field is analyzed and an appropriate size of the disk-type electrode is devised. On the basis of the theoretical model of the ER fluid under squeeze mode operation, the yield stress and response speed of the ER fluid are distilled from the time responses of squeeze force to the step electric potentials. Measured squeeze forces under various excitation conditions are compared with the predicted ones from Bingham model and time constant obtained at the transient response test. In addition, the controllability of the field-dependent damping force of the ER fluid under squeeze mode is experimentally demonstrated by implementing simple PID controller.

AC PDP의 온도에 따른 방전 특성 연구 (A Study on the Temperature-Dependent Discharge Characteristics in Alternating Current Plasma Display Panel)

  • 이석현;김지용
    • 전기학회논문지
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    • 제56권3호
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    • pp.577-582
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    • 2007
  • The plasma display panel is an image expression display using gas discharge plasma. However, gas discharge characteristics vary with temperature as gas discharge is sensitive to temperature. The discharge time lag extends a lot in low temperature and it is known as the cause which hinders high speed addressing which is essential for the size enlargement of the panel. Accordingly this research aims at identifying the temperature-dependent discharge characteristic. The lower temperature becomes, the longer addressing discharge time lag becomes. Particularly the statistical time lag extends much in low temperature. The increasing of electric field shortens discharge time lag in low temperature. Also, when priming particles are sufficiently supplied, stable discharge can be performed regardless of the influence of temperature.

Heuristic Approach for Lot Sizing and Scheduling Problem with State Dependent Setup Time

  • Han, Jung-Hee
    • Industrial Engineering and Management Systems
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    • 제10권1호
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    • pp.74-83
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    • 2011
  • In this paper, we consider a new lot-sizing and scheduling problem (LSSP) that minimizes the sum of production cost, setup cost and inventory cost. Setup carry-over, setup overlapping, state dependent setup time as well as demand splitting are considered. For this LSSP, we develop a mixed integer programming (MIP) model, of which the size does not increase even if we divide a time period into a number of micro time periods. Also, we develop an efficient heuristic algorithm by combining a decomposition scheme with a local search procedure. Test results show that the developed heuristic algorithm finds a good quality (in practice, even better) feasible solution using far less computation time compared with the CPLEX, a competitive MIP solver.