• Title/Summary/Keyword: Cluster Reduction

Search Result 216, Processing Time 0.031 seconds

A Progress Report on the MMT/Hectospec Observation for M81 Fields

  • Sohn, Jubee;Ko, Youkyung;Lim, Sungsoon;Jang, In Sung;Lee, Myung Gyoon;Hwang, Narae;Kim, Sang Chul;Park, Hong Soo
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.39 no.2
    • /
    • pp.53.1-53.1
    • /
    • 2014
  • The M81 group is a nearby galaxy group hosted by M81, a twin galaxy of Milky Way. This galaxy group is considered as an ideal laboratory for near-field cosmology to understand mass assembly and evolution of galaxies in the group environment. We designed a project to investigate spectroscopic properties of globular cluster candidates in this group. We obtained spectra of globular cluster candidates using the MMT/Hectospec as a part of the K-GMT Science Program. Our main targets include globular cluster candidates of the M81 group member galaxies and those wandering in the intragroup region. We also observed supernova remnants and some background galaxies. Observing fields covered about 2 square degrees including three main galaxies of the M81 group. Using these spectra, we will identify globular clusters in the M81 group, and investigate their properties including age and metallicity. We will discuss the MMT/Hectospec data reduction processes, and future plan for this project.

  • PDF

APPLICATIONS OF SELF-REFERENCING METHOD TO THE VIRGO CLUSTER SPIRALS

  • Chung, Eun-Jung;Kim, Hyo-Young;Rhee, Myung-Hyun
    • Journal of The Korean Astronomical Society
    • /
    • v.38 no.4
    • /
    • pp.371-384
    • /
    • 2005
  • Self-referencing method in revised-OTFTOOL is a new method in On-The-Fly(OTF) observation mode. It uses the source free regions of the observed frame as references instead of the OFFs references. We already analyzed and discussed its proprieties and advantages in the previous paper. In this paper, we make a statistical study about the self-referencing method by applying it to OTF mapping data of 27 Virgo spiral galaxies. We found that the self-referencing method solves the crooked baseline problem for every datacube. It straightens the baseline, and conserves the emissions. Compared with other data processing, the median filtering task 'mwflt' in AIPS, to use self-referencing method is more effective and safe not only to straighten the baseline but also to conserve the emission. For the strong CO galaxies, the data obtained by self-referencing method shows scarcely any difference from those reduced by conventional OFFs references and AIPS median filtering in the range of uncertainties. Undetected CO emissions in datacubes of conventional OFFs references are also not detected in those of self-referencing method. The self-referencing method is expected to save the observing time and simplify data reduction processes. Besides this, using self-referencing method will offer emission-free references more safely.

A Study of CPLD Low Power Algorithm using Reduce Glitch Power Consumption (글리치 전력소모 감소를 이용한 CPLD 저전력 알고리즘 연구)

  • Hur, Hwa Ra
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.5 no.3
    • /
    • pp.69-75
    • /
    • 2009
  • In this paper, we proposed CPLD low power algorithm using reduce glitch power consumption. Proposed algorithm generated a feasible cluster by circuit partition considering the CLB condition within CPLD. Glitch removal process using delay buffer insertion method for feasible cluster. Also, glitch removal process using same method between feasible clusters. The proposed method is examined by using benchmarks in SIS, it compared power consumption to a CLB-based CPLD low power technology mapping algorithm for trade-off and a low power circuit design using selective glitch removal method. The experiments results show reduction in the power consumption by 15% comparing with that of and 6% comparing with that of.

The Improvement of Surface Roughness of Poly-$Si_{1-x}Ge_x$Thin Film Using Ar Plasma Treatment (아르곤 플라즈마처리에 의한 다결정 $Si_{1-x}Ge_x$박막의 표면거칠기 개선)

  • 이승호;소명기
    • Journal of the Korean Ceramic Society
    • /
    • v.34 no.11
    • /
    • pp.1121-1128
    • /
    • 1997
  • In this study, the Ar plasma treatment was used to improve the surface roughness of Poly-Si1-xGex thin film deposited by RTCVD. The surface roughness and the resistivity of Si1-xGex thin film were investigated with variation of Ar plasma treatment parameters (electrode distance, working pressure, time, substrate temperature and R.F power). When the Ar plasma treatment was used, the cluster size decreased by the surface etching effect due to the increasing surface collision energy of particles (ion, neutral atom) in plasma under the conditions of decreasing electrode distance and increasing pressure, time, temperature, and R. F power. Although the surface roughness value decreased by the reduction of the cluster size due to surface etching effect, however, the resistivity increased. This may be due to the surface damage caused by the increasing surface collision energy. It was concluded that the surface roughness could be improved by the Ar plasma treatment, while the resistivity was increased by the surface damage on the substrate.

  • PDF

An Experimental Suggestion on the Transformation of Korean Energy Policies (한국 에너지 정책체계의 전환방안 연구)

  • Park, Jung-Gu
    • Journal of Energy Engineering
    • /
    • v.19 no.1
    • /
    • pp.1-7
    • /
    • 2010
  • This experimental study suggests some alternatives for stable growth and environmental conservation, responding to the unstability of global energy market and the regulations to greenhouse gas reduction. It introduces the energy-chain approach optimizing the whole processes extending energy production, transfer, and exploitation. And the alternatives are covered from low-carbon & environment-friendly energy-specific innovation system, transformation of major industries to low-carbon & environment-friendly industries, upgrading of energy efficiency, procurement of energy sources to policy cluster.

Analysis of Food Industry Cluster and Value-chain Network in the Northern Area of the Korean Peninsula (한반도 북방지역의 식량산업 클러스터 및 가치사슬 네트워크 분석)

  • Moon, Seung-Woon;Kim, Euijune
    • Journal of Korean Society of Rural Planning
    • /
    • v.23 no.3
    • /
    • pp.147-161
    • /
    • 2017
  • Climate changes from global warming and reduction in agricultural land result in volatility of prices of agricultural products, causing a imbalance of food market in Korea. It is necessary to develop a transnational food industry cooperation system among Korea, China and Russia that directly or indirectly affect food industry in terms of the whole industrial network. This study analyzes the value chain and linkage in the agriculture, forestry and fisheries industries in three nations. The unit structure and the industrial patterns of three nations were derived using the World Input-output Table (WIOT) from 2004 to 2014 every five years. This paper is expected to contribute to develop food security cooperation in the northern part of the Korean peninsula and to promote the mutual growth of food industry through industry linkage and cooperation.

RF Plasma Processes Monitoring for Fluorocarbon Polluted Plasma Chamber Cleaning by Optical Emission Spectroscopy and Multivariate Analysis (Optical Emission Spectra 신호와 다변량분석기법을 통한 Fluorocarbon에 의해 오염된 반응기의 RF 플라즈마 세정공정 진단)

  • Jang, Hae-Gyu;Lee, Hak-Seung;Chae, Hui-Yeop
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2015.11a
    • /
    • pp.242-243
    • /
    • 2015
  • Fault detection using optical emission spectra with modified K-means cluster analysis and principal component anal ysis are demonstrated for inductive coupl ed pl asma cl eaning processes. The optical emission spectra from optical emission spectroscopy (OES) are used for measurement. Furthermore, Principal component analysis and K-means cluster analysis algorithm is modified and applied to real-time detection and sensitivity enhancement for fluorocarbon cleaning processes. The proposed techniques show clear improvement of sensitivity and significant noise reduction when they are compared with single wavelength signals measured by OES. These techniques are expected to be applied to various plasma monitoring applications including fault detections as well as chamber cleaning endpoint detection.

  • PDF

$^{13}C$ and $^{57}Fe$ END OR of Nitrogenase: Can it Tell the Substrate-Binding Site in the Active Site?

  • 이홍인
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 2002.06b
    • /
    • pp.18-18
    • /
    • 2002
  • Nitrogenase, comprised of the MoFe and Fe proteins, catalyzes the reduction of dinitrogen to ammonia at ambient temperature and pressure. The MoFe protein contains two metal centers, the P-cluster (Fe8S7-8) and the FeMo-cofactor (Fe7S9:homocitrate), the substrate binding site. Despite the availability of the crystal structure of the MoFe protein, suprisingly little is known about the molecular details of catalysis at the active site, and no small-molecule substrate or inhibitor had ever been shown to directly interact with a protein-bound cluster of the functioning enzyme, until our electron-nuclear double resonance(ENDOR) study of CO-inhibited nitrogenase.(omitted)

  • PDF

Morphology of the Inclusion as the Al Deoxidation Product of Molten Iron (용융철에서 알루미늄 탈산 생성 개재물의 형상)

  • Lee, Bong-Ok;Lee, Kyung-Ku
    • Journal of Korea Foundry Society
    • /
    • v.19 no.6
    • /
    • pp.466-471
    • /
    • 1999
  • To investigate inclusions(oxides) which cause some trouble in the quality of the metal and a steel-making process, samples were manufactured. The molten irons were deoxidized using Al deoxidizer, and the morphology of the deoxidation products and the process of deoxidation were investigated by optical microscope, scanning electron microscope (SEM) and energy dispersive X-ray spectrometer(EDS). The reactions between Fe melt and Al deoxidizer formed deoxidation product, and those reaction may accelerates the reduction of oxide in Fe melt. According to the results of SEM analysis after deoxidizing treatment, it was found that deoxidation products had spherical cluster shape when 1% Al was added and dendritic shape with $2{\sim}3%$ A1 addition. The deoxidation products were globular, dendritic, polygonal(square) and cluster shape.

  • PDF

A Study on the Optimization of Stowage Planning for Container Terminal Considered by Hatch (Hatch를 고려한 컨테이너 터미널 적재순서 최적화 연구)

  • Lee, Sang-Heon;Kim, Moon-Gyu;Ahn, Tae-Ho
    • IE interfaces
    • /
    • v.19 no.4
    • /
    • pp.270-280
    • /
    • 2006
  • The shipping plan for an efficient augmentation of terminal is NP-hard problem which is subordinate to a shipping quantity. The load location problem and stowage planning problem are two important tactical problems for the efficient operations of container terminals. This paper is concerned with reduction of feasible region in constraints for stowage planning. After designing model which minimizes the number of shifting and the travel distance of the transfer crane, the simulated annealing algorithm is employed to search optimal solution quickly and accurately. In order to apply more realistic approach, the partial restriction through adding hatch is complemented to stowage planning decision problem applied in cluster. A variety of numerical experiments demonstrated that solutions by simulated annealing algorithm are useful and applicable in practice.