• Title/Summary/Keyword: Internal Processes

Search Result 730, Processing Time 0.024 seconds

Analysis on New Research Opportunities and Strategies for Earth Sciences in the United States (미국 지질과학분야 신규 연구주제 및 전략분석)

  • Kim, Seong-Yong;Ahn, Eun-Young;Bae, Jun-Hee;Lee, Jae-Wook
    • Economic and Environmental Geology
    • /
    • v.49 no.1
    • /
    • pp.43-52
    • /
    • 2016
  • The essential role of the Division of Earth Sciences(EAR) in the Directorate of Geoscience(GEO) of National Science Foundation of America(NSF) is to support basic research aimed at acquiring fundamental knowledge of the Earth system that can be directly applied to the United States' strategic needs. The 2011 Committee on New Research Opportunities in the Earth Sciences(NROES) of the National Academy of Sciences(NAS) identified specific areas of the basic earth science research scope of the EAR that were poised for rapid progress during the next decade. Quantified by interdisciplinary approaches, the Committee highlighted the following topics relating to the EAR Deep Earth Processes and Surface Earth Processes sections: (1) the early Earth; (2) thermochemical internal dynamics and volatile distribution; (3) faulting and deformation processes; (4) interactions among climate, the Earth surface processes, tectonics, and deep Earth processes; (5) co-evolution of life, environment, and climate; (6) coupled hydrogeomorphic-ecosystem response to natural and anthropogenic change; and (7) interactions of biogeochemical and water cycles in terrestrial environments. We also promote future research challenges such as the critical zone studies. In order to promote more active such a huge future research challenges, additional research support policies are needed.

Automatic Parameter Tuning for Simulated Annealing based on Threading Technique and its Application to Traveling Salesman Problem

  • Fangyan Dong;Iyoda, Eduardo-Masato;Kewei Chen;Hajime Nobuhara;Kaoru Hirota
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2003.09a
    • /
    • pp.439-442
    • /
    • 2003
  • In order to solve the difficulties of parameter settings in SA algorithm, an improved practical SA algorithm is proposed by employing the threading techniques, appropriate software structures, and dynamic adjustments of temperature parameters. Threads provide a mechanism to realize a parallel processing under a disperse environment by controlling the flux of internal information of an application. Thread services divide a process by multiple processes leading to parallel processing of information to access common data. Therefore, efficient search is achieved by multiple search processes, different initial conditions, and automatic temperature adjustments. The proposed are methods are evaluated, for three types of Traveling Salesman Problem (TSP) (random-tour, fractal-tour, and TSPLIB test data)are used for the performance evaluation. The experimental results show that the computational time is 5% decreased comparing to conventional SA algorithm, furthermore there is no need for manual parameter settings. These results also demonstrate that the proposed method is applicable to real-world vehicle routing problems.

  • PDF

Stellar and Ionized Gas Kinematics of Blue-cored Early-type Dwarf Galaxies in the Virgo Cluster

  • Chung, Jiwon;Rey, Soo-Chang;Kim, Suk;Lee, Youngdae;Lee, Woong;Sung, Eon-Chang
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.40 no.2
    • /
    • pp.49.3-50
    • /
    • 2015
  • Early-type dwarf galaxy (ETDG), the most abundant galaxy type in clusters, were recently shown to exhibit a wide variety in their properties. Particularly, the presence of blue cores in some ETDGs supports the scenario of late-type galaxy infall and subsequent transformation into red, quiescent ETDGs. While several transformation mechanisms for these ETDGs with blue core within cluster environment have been proposed, all these processes are able to explain only some of the observational properties of ETDGs such as stellar populations and structural parameters. In this context, internal kinematic properties of blue-cored ETDGs provide the most crucial evidence to discriminate different processes for the formation of these galaxies. We present a kinematic analysis of two blue-cored ETDGs in the Virgo cluster based on long-slit data obtained from Gemini Multi-Object Spectrographs (GMOS) observations. We find that the observed galaxies show kinematically decoupled sub-components in the velocity profile such as discontinuity or counter-rotating component. We discuss possible scenarios of formation of these transitional galaxies.

  • PDF

The primary cilium as a multiple cellular signaling scaffold in development and disease

  • Ko, Hyuk-Wan
    • BMB Reports
    • /
    • v.45 no.8
    • /
    • pp.427-432
    • /
    • 2012
  • Primary cilia, single hair-like appendage on the surface of the most mammalian cells, were once considered to be vestigial cellular organelles for a past century because of their tiny structure and unknown function. Although they lack ancestral motility function of cilia or flagella, they share common ground with multiciliated motile cilia and flagella on internal structure such as microtubule based nine outer doublets nucleated from the base of mother centrioles called basal body. Making cilia, ciliogenesis, in cells depends on the cell cycle stage due to reuse of centrioles for cell division forming mitotic spindle pole (M phase) and assembling cilia from basal body (starting G1 phase and maintaining most of interphase). Ciliary assembly required two conflicting processes such as assembly and disassembly and balance between these two processes determines the length of cilia. Both process required highly conserved transport system to supply needed substance to grow tip of cilia and bring ciliary turnover product back to the base of cilia using motor protein, kinesin and dynein, and transport protein complex, IFT particles. Disruption of ciliary structure or function causes multiple human disorder called ciliopathies affecting disease of diverse ciliated tissues ranging from eye, kidney, respiratory tract and brain. Recent explosion of research on the primary cilia and their involvement on animal development and disease attracts scientific interest on how extensively the function of cilia related to specific cell physiology and signaling pathway. In this review, I introduce general features of primary cilia and recent progress in understanding of the ciliary length control and signaling pathways transduced through primary cilia in vertebrates.

Economic Evaluations of Direct/indirect Coal Liquefaction Processes (직.간접석탄액화공정의 경제성 평가)

  • Park, Joo-Won;Bae, Jong-Soo;Kweon, Yeong-Jin;Kim, Hak-Joo;Jung, Heon;Han, Choon
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.06a
    • /
    • pp.857-860
    • /
    • 2009
  • This report examines the economic feasibility of a commercial 50,000 barrel per day direct/indirect coal liquefaction (DCL/ICL) facility to produce commercial-grade diesel and naphtha liquids from medium-sulfur bituminous coal. The scope of the study includes capital and operating cost estimates, sensitivity analysis and a comparative financial analysis. Based on plant capacity of 50,000BPD, employing Illinois #6 bituminous coal as feed coal the total capital cost appeared $3,994,858,000(DCL) and $4,942,976,000(ICL). Also, the internal rate of return of DCL/ICL appeared 13.27% and 12.68% on the base condition. In this case, coal price and sale price of products were the most influence factors. And ICL's payback period(6.8 years) was longer than DCL's (6.6 years). According to sensitivity analyses, the important factors on DCL/ICL processes were product sale price, feed coal price and the capital cost in order.

  • PDF

A study for cyclic Process technique of mineral base engine used oil resource (Engine 폐유 자원순환 기술에 관한 연구)

  • 김주항
    • Journal of the Korean Professional Engineers Association
    • /
    • v.18 no.2
    • /
    • pp.6-15
    • /
    • 1985
  • A new process disregraded the H$_2$SO$_4$ treatment process heretofore in use, was developed and substituted for mineral base engine used oil of homemade SAE-30 grade H.V.I., which was used covering 4,500km, as samples, and the following results in research, was obtained. (1) A good quality of rerefinded base oil was obtained through roughly a course of developed processes of vacuum distillation process, solvent extraction process, neutralization treatment process and clay treatment process. (2) Through vacuum distillation process, the size of fine grains of insoluble colloid carbon that is, colloid carbon which was produced by burning of internal combustion engine oil and fuel, could be brought up and precipitated (3) The insoluble matters and admixtures could be easily dispersed and dissolved by mixing and extracting solvent disregarded the H$_2$SO$_4$ treatment process heretofore in use (4) waste matter heretofore called acid sludge in consequence of the process, did not appear at all. accordingly, the environmental pollution could be removed. (5) The troubles of corrosion to copper strip which was faults of the usual used oil refined products and peculiar offensive odor of the rerefined oil, could be solved through the neutralization process. (6) The yield of rerefined oil obtained through a course of processes was over 86 percent, and it is of practical use, not to speak of commercial value.

  • PDF

Numerical Simulation of In-Cylinder Flow for the Axi-symmetric Model Engine by Low Reynolds Number k-ε Turbulence Model (저레이놀즈수 k-ε 난류모형에 의한 축대칭 모형기관 실린더내 유동의 수치해석)

  • Kim, W.K.;Choi, Y.D.
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.2 no.1
    • /
    • pp.38-50
    • /
    • 1994
  • To improve the efficiency of internal combustion engines, it is necessary to understand mixed air-fuel in-cylinder flow processes accurately at intake and compression strokes. There is experimental and numerical methods to analyse in-cylinder flow process. In numerical method, standard $k-{\varepsilon}$ model with wall function was mostly adopted in in-cylinder flow process. But this type model was not efficiently predicted in the near wall region. Therefore in the present study, low Reynolds number $k-{\varepsilon}$ model was adopted near the cylinder wall and standard $k-{\varepsilon}$ model in other region. Also QUICK scheme was used for convective difference scheme. This study takes axisymmetric reciprocating model engine motored at 200rpm with a centrally located valve, incorporated 60 degree seat angie, and flat piston surface excluding inlet port. Because in-cylinder flow processes are undergoing unsteady and compressible, averaged cylinder pressure and inlet velocity at arbitrary crank angle are determined from thermodynamic analytic method and incylinder states at that crank angle are iteratively determined from the numerical analytic method.

  • PDF

Use of modern microscopes in Analyzing fiber and Paper Properties( I )-Use of CLSM in Analyzing Fiber and Paper Properties- (최신 현미경을 이용한 섬유 및 종이의 성질 분석(제1보)-Confocal Laser Scanning Microscope를 이용한 섬유 밑 종이의 성질 분석-)

  • ;Keith Roy Wadhams
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.30 no.1
    • /
    • pp.7-17
    • /
    • 1998
  • With the advent of CLSM in the end of 1980s, it has been applied to the field of pulp and paper science in various ways. This study showed the potentials of CLSM In analyzing a change of pulp fiber and paper properties before and after mechanical treatment. In particular, a quantification of internal fibrillation has been done using cross-sectional images of fibers and image analysis technique, then evaluated the effects of fiber wall delamination on fiber and paper properties. It showed that the delaminated fibers were closely associated to development of the interfiber bonding in a fiber network. The CLSM made it possible to investigate a density profile along the sheet thickness, which was created by some papermaking processes like pressing, drying and calendering. Through the attempt to observe the forming procedure of a fiber network during handsheet making, the CLSM images showed that the pressing stage was considered greatly to contribute to generation of interfiber bonding with removing a free water and partly a bound water between fibers. In addition, the CLSM could be used to illustrate not only a surface profile of paper showing the extent of smoothness or roughness, but also a density profile in a B-direction of the network. Finally it became evident that the CLSM could be used as an excellent tool to predict development in fiber and paper properties before and after mechanical treatment during papermaking processes.

  • PDF

Intrinsic Flux Inequality in Forward Osmosis (FO) and Pressure-Retarded Osmosis (PRO) Processes (수학적 귀납법을 이용한 정삼투 및 압력지연삼투 공정의 투과율 불균형 해석)

  • Kim, Albert S.;Lee, Seung-won
    • Membrane Journal
    • /
    • v.25 no.4
    • /
    • pp.367-372
    • /
    • 2015
  • In pressure-retarded osmosis (PRO) and forward osmosis (FO) processes, solvent (permeate) flux depends on which surface the draw solution faces. There are two operation modes. PRO mode indicates that the active layer faces the draw solution, and FO mode means that the porous substrate fronts the draw stream. It is often observed that the PRO mode produces higher flux than that of FO under the same operating conditions. The current work uses the method of proof by contradiction, and mathematically proves the intrinsic flux inequality between the two modes.

Development a multidimensional assessment scale for work-family spillover in working couples with children (유자녀 맞벌이 부부의 다차원적 일-가족 전이 척도 개발)

  • Jang, Yoon-Ok;Jeong, Seo-Leen
    • Journal of Family Resource Management and Policy Review
    • /
    • v.17 no.3
    • /
    • pp.59-79
    • /
    • 2013
  • The purpose of this study was to develop and validate a scale for the multidimensional assessment of work-family spillover in working couples with children. The subjects of this study were working wives and husbands with children in Daegu. Two surveys were administered, eliciting 243 respondents and 227 respondents, respectively. Then a series of tests were run to analyze the data, including item-to-total correlation, Cramer's V coefficients, item discrimination, Cronbach's ${\alpha}$, and exploratory and confirmatory factor analysis. The results yielded that, first, a preliminary 102 items were developed on the basis of the literature review, and this was narrowed down to 72 items selected with the help of experts. Through preliminary, primary and secondary survey analysis, the scale for the multidimensional assessment of work-family spillover was developed and validated, with a 36 items scale, 18 items for work to family spillover and 18 items for family to work spillover. Furthermore, the scale constructed three spillover processes - time interference, energy depletion, and psychological distraction - and consisted of four different domains of family life into which spillover occurs - namely marital relationship, parent-child relationship, leisure, and housework. The internal reliability was evaluated to show a confidence range of .85 ~.92 for each factor.

  • PDF