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991.
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In order to provide statistically reliable information of a wind energy site, accurate analysis on the atmospheric stability and climate characteristics in a certain area is a prerequisite. Two 2-D ultrasonic anemometers and one cup anemometer, located perpendicular to the prevailing wind direction, were used to measure the atmospheric wind environment at a height of 4.5 m in coastal region of the Wol–Ryong, Jeju, South Korea. The study is aiming to understand the atmospheric stability about a coastal region, and the effect of roughness length. We calculate the Monin–Obukhov length for division of atmospheric stability about unstable regime, neutral regime and stable regime. The distribution of diurnal Monin–Obukhov length is highly sporadic in the coastal region due to the effect of radiant heat from the surface or other environmental effects. In order to calculate the roughness length in coastal region, three different methods are applied in terms of the surface roughness, flow fluctuation and gust wind, which are called logarithmic profile, standard deviation and gust factor methods. In the study, the atmospheric stability was insignificant when applying these three methods. In the results, three different roughness length scales sufficiently showed the effect of obstacle and surface conditions around the measurement position. On the basis of an overall analysis of the short-term data measured in the Wol–Ryong area, Jeju Island, it is concluded that for the development of future wind energy resources, the Wol–Ryong site could be a good candidate for a future wind energy site. 相似文献
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994.
Shuai Liu Yujie Wu Teng Lin Robert Abel Jonathan P. Redmann Christopher M. Summa Vivian R. Jaber Nathan M. Lim David L. Mobley 《Journal of computer-aided molecular design》2013,27(9):755-770
Alchemical free energy calculations hold increasing promise as an aid to drug discovery efforts. However, applications of these techniques in discovery projects have been relatively few, partly because of the difficulty of planning and setting up calculations. Here, we introduce lead optimization mapper, LOMAP, an automated algorithm to plan efficient relative free energy calculations between potential ligands within a substantial library of perhaps hundreds of compounds. In this approach, ligands are first grouped by structural similarity primarily based on the size of a (loosely defined) maximal common substructure, and then calculations are planned within and between sets of structurally related compounds. An emphasis is placed on ensuring that relative free energies can be obtained between any pair of compounds without combining the results of too many different relative free energy calculations (to avoid accumulation of error) and by providing some redundancy to allow for the possibility of error and consistency checking and provide some insight into when results can be expected to be unreliable. The algorithm is discussed in detail and a Python implementation, based on both Schrödinger’s and OpenEye’s APIs, has been made available freely under the BSD license. 相似文献
995.
Jooyoung Chung Jihyun Myoung Jisook Oh Sangwoo Lim 《Journal of Physics and Chemistry of Solids》2012,73(4):535-539
Thin ZnSe layers were deposited on ZnO nanowires by a novel successive ionic layer adsorption and reaction technique in order to solve recombination problems in ZnO nanowire-based dye-sensitized solar cells (DSSCs). Cell efficiency increased from 0.1 to 1.3–1.4% with the deposition of a 9- to13-nm-thick ZnSe shell on ZnO nanowires due to a large increase in JSC. The dramatic increase in JSC and cell efficiency is due to the facilitation of electron transfer related to ambipolar diffusion by the formation of a type II band alignment and the suppression of recombination in the presence of the ZnSe shell. 相似文献
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Study of three-dimensional deformation of a pallet using phase-shiff shadow moiré and finite-element analysis 总被引:3,自引:0,他引:3
We present the results of a comparative study on the static deformation of a pallet, made from oil-palm fiberreinforced composite
material, using the phase-shift shadow moiré method and finite-element analysis (FEA). The pallet was designed and analyzed
using a commerical software package. The effect of various joint types on the deformation profile was studied to obtain a
simplified model to represent the actual design. A one-fifth scale model of the pallet was fabricated and the deformation
due to static loading was measured using the phase-shift shadow moiré method. The comparison between the measurement and FEA
results on the deformed profile showed a maximum difference of 13.7% at the center of the some of the deck boards, but a smaller
difference at other deck boards. The FEA results also produced a larger deformation gradient compared to the measurements. 相似文献