• 제목/요약/키워드: Mid-region

검색결과 668건 처리시간 0.036초

Mid-IR Luminosity Functions of Local Galaxies in the North Ecliptic Pole Field

  • Kim, Seong Jin;Lee, Hyung Mok;Jeong, Woong-Seob
    • 천문학회보
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    • 제40권1호
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    • pp.72.3-72.3
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    • 2015
  • We present the mid-infrared (MIR) luminosity function (LF) of local (z < 0.3) star forming (SF) galaxies based on the AKARI's NEP-Wide Survey data. We utilized a combination of the NEP-Wide point source catalogue containing a large number (114,000) of infrared (IR) sources distributed over the wide (5.4 sq. deg) field and spectroscopic redshift (z) data for 1790 selected targets obtained by optical follow-up surveys with MMT/Hectospec and WIYN/Hydra. The AKARI's continuous 224μm wavelength coverage and the spectroscopic redshifts for sample galaxies enable us to derive accurate spectral energy distributions (SEDs) in the mid-infrared. We carried out SED-fit analysis and employed 1/Vmax method to derive the mid-IR (e.g., 8μm, 12μm, and 15μm rest-frame) luminosity functions. Our results for local galaxies from the NEP region generally consistent with various previous works for other fields over wide luminosity ranges. The comparison with the results of the NEP-Deep data implies the luminosity evolution from higher redshifts towards the present epoch. We attempted to fit our derived LFs to the double power-laws and present the resulting power indices. We also examined the correlation between mid-IR luminosity and total IR luminosity.

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Effect of Transplanting Time on the Physicochemical Properties of Starch in Different Mature Rice Varieties

  • Jong-Hee Shin;Chae-Min Han;Young-Un Song;Sang-Kuk Kim;Jung-Gi Ryu
    • 한국작물학회지
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    • 제68권2호
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    • pp.35-46
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    • 2023
  • The transplanting period limit considering the rice yield in the Dague region, the inland plains of Gyeongsangbuk-do, was estimated to be July 15th for early and mid-maturing rice and July 5th for mid-late maturing rice. However, as the transplanting time was delayed, the characteristics of rice starch changed significantly. In the case of early and mid-maturing rice varieties, the starch granule size increased as the transplanting time was delayed; the opposite tendency was observed for mid-late maturing varieties. In all mature rice types, the late transplanting resulted in a longer pasting time and a higher pasting temperature. In addition, the peak viscosity, breakdown, and gelatinization temperature were significantly lowered, the relative crystallinity degree decreased, and the setback was significantly increased. In the case of Ilpum, a mid-late maturing rice variety, the distribution of amylopectin short chains tended to increase when rice was transplanted on June 30th.

촉매 변환기 내부 유동의 실험적 해석 (Experimental Analysis on the Catalytic Converter Internal Flow)

  • 유성출
    • 한국가시화정보학회지
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    • 제10권2호
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    • pp.20-24
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    • 2012
  • Increasing the active catalyst surface area is important in improving a converter's efficiency. In addition, uniform flow is advantageous in that it produces more efficient catalytic conversion. This results in the ability to use a smaller catalytic converter with uniform flow as opposed to a larger converter requirement for non-uniform flow. Therefore, it is important to characterize the internal flow of the catalytic converter. To characterize the system's flow patterns, velocity measurements were taken at the mid and exit planes of a ceramic honeycomb catalytic converter at flow rates of 37.8 l/s and 94.4 l/s. Measurements were conducted using LDV. The profiles were measured along both the major and minor axis of the planes. Primary flow direction velocities measured along the minor axis, at both flow rates, varied greatly at the mid plane and somewhat at the exit plane. The areas of greatest air flow were seen near the edges of the walls and on the side of the converter opposite the flow's entrance region. It also appears that the high velocities opposite the intake are due to the design of the entrance region. The entrance region is possibly too small to properly redirect the vertically entering fluid into an evenly distributed flow in the primary flow direction.

낙동강 중류 지역의 통합적 유역환경평가 및 유형화 (An Integrated Watershed Environmental Assessment and Classification of the Mid-Nakdong River Region)

  • 정성관;박경훈
    • 환경영향평가
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    • 제13권3호
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    • pp.137-151
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    • 2004
  • Many of today's environmental problems are regional in scope and their effects overlap and interact. The purpose of this paper is to developed a simple method for an integrated assessment of environmental conditions across the Mid-Nakdong River Region, by combining data on land use, impervious cover, roads, streams, riparian areas, forest patches, population, pollutant loadings, soil erosion and topography. A cluster analysis was used to identify groups of sub-watersheds with similar environmental characteristics. The mean value for each group was used to find watershed that may be more vulnerable to future environmental degradation. Watersheds in cluster I and II had high amount of forest, but the amount of riparian vegetation was low. Watersheds in cluster III, which located in the middle Geumho River and the main course of Nakdong River, had a greater proportion of their agriculture, a greater proportion of agriculture on steep slopes, and less forest adjacent to streams. Watersheds in cluster IV and V were in the most urbanized areas of the region. The principal adverse impacts for watersheds in this group were high scores for urban area, impervious cover, pollutant loadings, population density, forest fragmentation, and low amounts of forest and riparian forest cover. Notwithstanding the exploratory nature of cluster analysis, it appears to be a useful tool for grouping watersheds with similar environmental characteristics.

용접 저온균열 감수성에 미치는 중심 편석의 영향 (Effects of Center Segregation on Weld Cold Cracking Susceptibility)

  • 안영호;이종봉;장래웅;소문섭
    • Journal of Welding and Joining
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    • 제12권2호
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    • pp.87-96
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    • 1994
  • Correlation between microstructural features and segregation of elements (Si, Mn, P and S) near the mid of thickness in the base metal and the synthetic HAZ was investigated. Furthermore, the relationship between the degree of center segregation and weld cold cracking susceptibility in the thickness direction was also conducted by evaluating the effect of P concentration on the critical applied stress. The results obtained are as follows: 1) Pearlite band, containing the MnS type inclusion and a locally transformed structure with a higher hardness, was observed in the center segregation region. 2) By the weld thermal cycle, center segregation region was transformed to the white band which had a higher hardness than that of base metal due to a greater hardenability of concentrated Mn, P etc.. 3) Weld cold cracking susceptibility in the thickness direction was mainly dependent on the concentration of impurity elements rather than on the number of the segregated particles near the mid of thickness. 4) During welding, the higher concentrated region was easily changed into white band. Therefore, it could be predicted that the initiation and propagation of a cold crack would be promoted by increasing the restraint stress and hydrogen content.

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녹두 파종기에 따른 수량과 Flavonoid 함량 변화 (Effect of Seeding Times on Yield and Flavonoid Contents of Mungbean)

  • 김동관;천상욱;이경동;김경호;임요섭;정석철
    • 한국작물학회지
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    • 제53권3호
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    • pp.273-278
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    • 2008
  • 본 연구는 남부지역에서 5월 중순부터 7월 중순까지 파종기에 따른 녹두 생육과 수량 변이 및 vitexin과 isovitexin 함량 변화 등을 구명하고자 수행하였다. 1. 파종기가 늦을수록 개화일수, 성숙까지 일수와 재배기간이 짧았다. 반면에1차 성숙 후1차 수확까지(소요)일수, 각 수확기 간 소요일수는 길었다. 2. 수량은 1차 수확기 개체당 협수가 15.3개로 많은 6월 하순 파종이 가장 많았고, 표준 파종기 6월 상순보다 14%가 많았다. 반면에1차 수확기 협당 립수와 천립중은 7월 중순 파종이 가장 높았다. 3. 녹두 파종기별 수확횟수는 6월 하순과 7월 중순 파종이 2회로 가장 적었다. 4. 녹두 종실의 vitexin과 isovitexin 평균 함량은 7월 중순, 6월 하순, 5월 중순 파종 순으로 많았고, 특히 2차 수확 종실에서 이들 함량이 가장 높았다. 5. 이상의 재배기간, 수량, 수확횟수 및 vitexin, isovitexin 함량 등을 감안할 때 남부지역 녹두 파종적기는 6월 하순에서 7월 중순으로 보아진다.

THEORY AND PRINCIPLES OF NEAR INFRARED SPECTROSCOPY

  • Barton, Franklin E.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1012-1012
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    • 2001
  • The elegant early experiments of Herschel demonstrated that there is light after the visible spectrum in a region we call the near infrared (NIR). This was followed by the work which showed that the spectrum went further into what we call the mid infrared (MIR). The MIR has been used for many years as a qualitative and quantitative region to measure constituent values. The MIR region contains the fundamental vibrations which can be theoretically calculated from symmetry rules and harmonic oscillator equations. The NIR is not as straight forward because the region from 400-2500 nm does not contain any of the fundamental vibrations only combination bands and overtones. Over the past fifty years efforts to understand the NIR have largely been ignored while the quantitative aspects of the region have been utilized. This presentation will focus on the efforts to define terms for NIR, examine the calculation of combination bands and overtones and ways to interpret the spectra. The interpretation of the NIR has been aided greatly in recent years by the use of two dimensional spectroscopy which allows the correlation of bands in one spectral region with that of the NIR.

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Mid-Infrared Luminosity Function of Local Galaxies in the North Ecliptic Pole Region

  • 김성진;이형목
    • 천문학회보
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    • 제38권1호
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    • pp.38.1-38.1
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    • 2013
  • We present observational estimation of the infrared (IR) luminosity function (LF) of local (z < 0.3) star-forming (SF) galaxies derived from the AKARI NEP-Wide samples. We made an analysis of the NEP-Wide data with optical spectroscopic information allowing an accurate determination of luminosity function. Spectroscopic redshifts for about 1650 objects were obtained with MMT/Hectospec and WIYN/Hydra, and the median redshifts is about 0.22. To measure the contribution of SF galaxies to the luminosity function, we excluded AGN sample by comparing their SEDs with various model template. Spectroscopic redshifts and the AKARI's continuous filter coverage in the mid-IR (MIR) wavelength (2 ~ 25 micron) enable us to avoid large uncertainties from the mid-IR SED of galaxies and corresponding k-corrections. The 8-micron luminosity function shows a good agreement with the previous works in the bright-end, whereas it seems not easy to constrain the faint-end slope. The comparison with the results of the NEP-Deep data (Goto et al. 2010) suggests the luminosity evolution to the higher redshifts, which is consistent with the down-sizing evolutionary pattern of galaxies.

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소형(小型) 동력경운기(動力耕耘機)의 적정(適正) 설계(設計)에 관한 연구(硏究) - 기관출력(機關出力)과 중량(重量)을 중심(中心)으로 - (Determination of Optimum Size of Power Tiller)

  • 류관희;김경욱;최규홍;박금주
    • Journal of Biosystems Engineering
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    • 제10권1호
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    • pp.1-12
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    • 1985
  • The two agricultural zones, mid-and-northen region and southern region, were established according to the possibility of double cropping in the paddy field. For each agricultural zone typically mechanized farming systems with a power tiller for cultivating rice, barley and soybean were established. A computer program, which determines the optimum size of power tiller for the given farm size, the ratio of paddy area to total area and the ratio of double cropping area to the paddy area, was developed. The computer program was executed for the farm sizes, 1 to 3 ha, and the ratios of paddy area to the total area, 60~80%, and the ratio of double cropping area to the total paddy area, 70%. The following conclusions were drawn from analyzing the computer outputs. 1. In the mid-and-northern region, a smaller power tiller (5 or 6 PS) appeared to be more economical for the farm size up to 3 ha. From the viewpoint of fuel consumption a 6 PS power tiller appeared to be more favorable. 2. In the southern region, a smaller tiller (5 or 6 PS) appeared to be more economical for the farm size up to 1.5 ha. But, a larger power tiller (8 or 10 PS) appeared to become more economical as the farm size and the barley planted area increased. 3. For the southern region where rotary tilling is heavily required due to double cropping, it is recommended to develop a power tiller which weighs light like the conventional 5 or 6 PS small power tiller but has lager power.

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팁간극 영역에서의 동익 표면 열부하 측정 (Measurement of Thermal Load in the Tip-Clearance Region of a Rotor Surface)

  • 이상우;권혁구;박진재
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.187-192
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    • 2003
  • The heat (mass) transfer characteristics in the tip-leakage flow region of a high-turning first-stage turbine rotor blade has been investigated by employing the naphthalene sublimation technique. The heat transfer data in the tip-leakage flow area for the tip clearance-to-span ratio, h/s, of 2.0% are compared with those in endwall three-dimensional flow region without tip clearance (h/s = 0.0 %). The result shows that the thermal load in the tip-leakage flow region for h/s = 2.0% is more severe than that in the endwall flow region for h/s = 0.0%. The thermal loads even at the leading and trailing edges for h/s = 2.0% are found larger than those for h/s = 0.0%. The tip-leakage flow results in heat transfer augmentations near the tip on both pressure and suction sides in comparison with the mid-span results.

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