• Title/Summary/Keyword: D.B.H. analysis

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Regional Stem Curve and Volume Function Model of Pinus densiflora in Kangwon-Province (강원도 지방 소나무의 지역(地域) 간곡선(幹曲線) 및 재적식(材積式) 모델)

  • Kim, Joon Soon;Lee, Woo Kyun;Byun, Woo Hyuk
    • Journal of Korean Society of Forest Science
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    • v.83 no.4
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    • pp.521-530
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    • 1994
  • Voume functions, which are usually expressed by the function of dbh and height, are estimated commonly through the regression analysis with the highest statistical accuracy considered. In Korea, general volume functions for each tree species were prepared by means of the regression analysis with the exponential function ($V=aD^bH^c$) having the dbh(D) and height(H) as independent variables. In this study, regional stem curve functions for the Pinus densiflora in Kangwon-province were derived and a regional volume function model, in which the stem volume can be directly estimated through the rotational integral of the regional stem curve functions, was prepared. The regional volume estimated by the prepared model was more accurate than the volume by the general volume table for the Pinus densiflora in Kangwon-province. Additionary, the form of stem curves derived by the regional stem curve functions showed difference from each other. The stem in Youngwol and Wonju taper down more fast in upper part than that in other regions. These various stem forms also led to the regional difference in volume estimates.

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Convective Heat Transfer Correlations for the Compact Heat Exchanger with Circular Tubes and Flat Tubes-Plate Fins (원형관 및 납작관-평판휜 형상의 밀집형 열교환기에 대한 대류열전달 상관관계식)

  • Moh, Jeong-Hah
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.3
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    • pp.291-299
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    • 2010
  • Aspect-ratio-based numerical analysis is carried out to investigate the air-side convective heat transfer characteristics in compact heat exchangers with circular tubes and flat tubes-plate fins. The RNG $k-{\varepsilon}$ model is adopted for turbulence analysis. The numerical analysis is carried out for aspect ratios ranging from 3.06 to 5.44 and for Reynolds numbers ranging from 1,000 to 10,000. The calculated results indicate a correlation between the friction factor and Colburn j factor in the compact heat exchanger system for the range of aspect ratios under consideration. The results obtained for circular tubes and flat tubes-plate fins in this study can be utilized to realize the optimal design of an air conditioning system.

Economic Analysis of the Livestock Manure Treatment System Using Life-Cycle Cost Technique (LCC 기법을 통한 가축분뇨처리시설의 경제성 분석)

  • Kim, J.H.;Cho, S.H.;Kwag, J.H.;Choi, D.Y.;Jeong, K.H.;Chung, U.S.;Chung, M.S.;Park, S.K.
    • Journal of Animal Environmental Science
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    • v.17 no.sup
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    • pp.61-68
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    • 2011
  • To assess the total cost with all stages of facilities, the feasibility of Life Cycle Cost (LCC) analysis was examined in this study to estimate the livestock manure treatment system and optimal decision making process. For the economic evaluation, the plant/equipment investment and annual operation cost of four Public Livestock Recycling Facilities, whose treatment capacity is 100 ton piggery manure per day, was compared. The initial cost was in the range of 2,699 million won to 3,202 million won, where T and E methods were highest and lowest, respectively. The annual operation cost was in the level of 378 million to 498 million won, which decreased in the following order : T method > J method > E method > B method. For the LCC analysis, 4.7% of interest rate, 3.13% of inflation rate, and 1.52% of net discount rate was considered by the data received from Bank of Korea and Statics Korea in the period of 2000 to 2009. Also, for the calculation of present value factor, the durable years of civil engineering & construction, machinery and electric instrument was 30 years, 10 years and 15 years, respectively. Based on these consideration, operation cost was in the range of 17,570 won/ton to 20,661 won/ton, and E method (17,570 won/ton) was economical and B method (20,661 won/ton) was non-economical. Though initial cost of T method was higher than that of B method, LCC analysis of T method was lower than that of T method due to the lower operation cost. Therefore, LCC analysis, which considers both initial cost and operation cost, is more reasonable evaluation method than either initial cost or annual operation cost. For the change of LCC analysis according to the uncertainty, the sensitivity analysis was carried out using fluctuation magnitude of discount rate in the period of 2000 to 2009. As a result, LCC analysis evaluated by discount rate was stable for the uncertain factors since the cost leadership did not change even though the sensitivity analysis varied. In summary, the economic evaluation using LCC analysis could be an efficient reference to choose the suitable livestock manure treatment plants. Furthermore, standardization of statement calculation for the actual cost analysis should be conducted and more detailed study is necessary to validate this summary. Therefore, the application of comprehensive technology evaluation, which considers LCC analysis, should contribute in obtaining objectivity and enhancing reliability for the 'Evaluation of Livestock Manure Treatment System and its Technology'.

A Calculation of C-V characteristics for HgCdTe Semiconductor material (HgCdTe 반도체 재료의 C-V 특성 계산)

  • Lee, S.D.;Kang, H.B.;Kim, B.H.;ADD, ATRC, D.H.Kim;Kim, J.M.
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.813-815
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    • 1992
  • Accurate Capacitance-Voltage characteristics of Metal-Insulator-Semiconductor (MIS) devices in narrow band-gap semiconductors are presented. The unique band structure of narrow band-gap semiconductors is taken into account such as non-parabolicity and degeneracy. Compensated and partially ionized impurities either in the bulk or the space charge region are also considered. HgCdTe is a defect semiconductor, so this approach is very important for characterization and analysis of MIS devices.

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Antioxidant Activity with Flavonoidal Constituents from Aerva persica

  • Ahmed Ejaz;Imran Muhammad;Malik Abdul;Ashraf Muhammad
    • Archives of Pharmacal Research
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    • v.29 no.5
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    • pp.343-347
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    • 2006
  • A new flavanone Persinol (1) and the new flavanone glucosides persinosides A (2) and B (3), along with known flavonoids (4 and 5) have been isolated from the ethyl acetate soluble fraction of the whole plants of Aerva persica. Their structures were elucidated on the basis of extensive analysis of nuclear magnetic resonance (1D & 2D-NMR) spectral data. All of them showed profound antioxidative activities by DPPH and cytochrome-c-reduction assays using the HL-60 cell culture system.

Structural Analysis of Cu Binding Site in [Cu(I)·d(CpG)·d(CpG)-2H]-1 Complex

  • Im, Yu-Jin;Jung, Sang-Mi;Kang, Ye-Song;Kim, Ho-Tae
    • Bulletin of the Korean Chemical Society
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    • v.34 no.4
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    • pp.1232-1236
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    • 2013
  • The Cu cation binding sites of $[Cu(I){\cdot}d(CpG){\cdot}d(CpG)-2H]^{-1}$ complex have been investigated to explain the $[Cu{\cdot}DNA]$ biological activity caused by the Cu association to DNA. The structure of $[Cu(I){\cdot}d(CpG){\cdot}d(CpG)-2H]^{-1}$ complex was investigated by electrospray ionization mass spectrometry (ESI-MS). The fragmentation patterns of $[Cu(I){\cdot}d(CpG){\cdot}d(CpG)-2H]^{-1}$ complex were analyzed by MS/MS spectra. In the MS/MS spectra of $[Cu(I){\cdot}d(CpG){\cdot}d(CpG)-2H]^{-1}$ complex, three fragment ions were observed with the loss of d(CpG), {d(CpG) + Cyt}, and {d(CpG) + Cyt + dR}. The Cu cation binds to d(CpG) mainly by substituting the $H^+$ of phosphate group. Simultaneously, the Cu cation prefers to bind to a guanine base rather than a cytosine base. Five possible geometries were considered in the attempt to optimize the $[Cu(I){\cdot}d(CpG){\cdot}d(CpG)-2H]^{-1}$ complex structure. The ab initio calculations were performed at B3LYP/6-31G(d) level.