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高稳定性程序控制固态脉冲激光电源

激光与红外 1972年第1期 32-34页

作者： erickson,l.e Spencer,C.M 太原工学院

本文叙述应用于红宝石激光器的一种高稳定性固态电源。在运转范围高达3000伏时,电源电压可以调节稳定至小于±1伏。电源采用程序控制,以供激光自动运转。

关键词：电源高稳定性充电电流激光头

Numerical studies towards practical large-eddy simulation

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Journal of Thermal Science 2007年第4期16卷 328-336页

作者： J.Boudet J.Caro l.Shao e.lév(?)que lMFA laboratoire

large-eddy simulation developments and validations are presented for an improved simulation of turbulent internal flows. Numerical methods are proposed according to two competing criteria： numerical qualities （precision and spectral characteristics）, and adaptability to complex configurations. First, methods are tested on academic test-cases, in order to abridge with fundamental studies. Consistent results are obtained using adaptable finite volume method, with higher order advection fluxes, implicit grid fil.ering and ＂low-cost＂ shear-improved Smagorinsky model. This analysis particularly focuses on mean flow, fluctuations, two-point correlations and spectra. Moreover, it is shown that exponential averaging is a promising tool for leS implementation in complex geometry with deterministic unsteadiness. Finally, adaptability of the method is demonstrated by application to a configuration representative of blade-tip clearance flow in a turbomachine.

关键词： leS adaptable methods validation

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Downscaling future climate scenarios to fine scales for hydrologic and ecological modeling and analysis

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ecological Processes 2012年第1期1卷 109-123页

作者： lorraine e Flint Alan l Flint U.S.Geological Survey Placer Hall6000 J St.SacramentoCA 95819USA

Introduction:evaluating the environmental impacts of climate change on water resources and biological components of the landscape is an integral part of hydrologic and ecological investigations,and the resultant land and resource management in the twenty-first *** of both climate and simulated hydrologic parameters on ecological processes are relevant at scales that reflect the heterogeneity and complexity of *** present,simulations of climate change available from global climate models[GCMs]require downscaling for hydrologic or ecological ***:Using statistically downscaled future climate projections developed using constructed analogues,a methodology was developed to further downscale the projections spatially using a gradient-inverse-distancesquared approach for application to hydrologic modeling at 270-m spatial ***:This paper illustrates a methodology to downscale and bias-correct national GCMs to subkilometer scales that are applicable to fine-scale environmental *** scenarios were chosen to bracket the range of future emissions put forth by the Intergovernmental Panel on Climate ***-scale applications of downscaled datasets of ecological and hydrologic correlations to variation in climate are ***:The methodology,which includes a sequence of rigorous analyses and calculations,is intended to reduce the addition of uncertainty to the climate data as a result of the downscaling while providing the fine-scale climate information necessary for ecological *** results in new but consistent data sets for the US at 4 km,the southwest US at 270 m,and California at 90 m and illustrates the utility of fine-scale downscaling to analyses of ecological processes infl.enced by topographic complexity.

关键词： downscaling climate change spatial scale scenarios

Advancements and chal.enges in treating advanced gastric cancer in the West

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World Journal of gastrointestinal Oncology 2019年第9期11卷 652-664页

作者： Jennifer l leiting Travis e Grotz Division of Hepatobiliary and Pancreas Surgery Mayo Clinic

gastric cancer is a leading cause of cancer incidence and death *** with advanced gastric cancer benefit from a multi-modality treatment *** oncologic resection with negative margins and complete lymphadenectomy plays a crucial role in long-term survival for patients with resectable *** utilization of minimally invasive techniques for gastric cancer has been slowly increasing and is proving to be both technically and oncologically *** chemotherapy is the current standard of care for advanced gastric cancer.A variety of chemotherapy regimens have been used with the combination of docetaxel,oxaliplatin,5-fluorouracil,and leucovorin being the current recommendation given its superior ability to induce a complete pathologic response and prolong *** use of radiation has been more controversial with its optimal place in the treatment sequence being *** are current ongoing studies assessing the impact of radiation as an adjunct or in place of *** treatments(e.g.,trastuzumab for human epidermal growth factor receptor 2 positive tumors and pembrolizumab for programmed death-ligand 1 positive tumors)are showing promise and are part of a continued emphasis on individualized *** chemotherapy may also play a role in preventing peritoneal recurrences for patients with high risk *** treatment of patients with advanced gastric cancer in the West continues to advance and improve with a better understanding of optimal treatment sequences and the utilization of personalized treatment regimens.

关键词： gastric cancer D2 lymphadenectomy Minimally invasive surgery Neoadjuvant chemotherapy Chemoradiation Targeted treatments

混合物性能的预计——科学研究和工程中混合法则

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塑料 1980年第4期 39-68页

作者： l.e尼尔生徐支祥七机部

第一章绪论§1.引言§2.混合物的分类§5.最简单的混合法则§4.通用的混合法则§5.浓度变量§6.混合法则为何可能不成立§7.参考文献第二章单相二元混合物§1.引言§2.单相混合物的一般方程§3.混合方程的图解§4.实例§5.参考文献第三... 详细信息

第一章绪论§1.引言§2.混合物的分类§5.最简单的混合法则§4.通用的混合法则§5.浓度变量§6.混合法则为何可能不成立§7.参考文献第二章单相二元混合物§1.引言§2.单相混合物的一般方程§3.混合方程的图解§4.实例§5.参考文献第三章具有一个连续相的两相混合物§1.引言§2.理论和一般混合法则§3.实例§4.参考文献第四章具有两个连续相的两相混合物§1.引言§2.混合法则§3.实例§4.参考文献

关键词：方程式标度组份常数方程数学混合法则液体混合物

effect of Modified Atmosphere Packaging on Postharvest Quality of Barangan Banana

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Journal of Food Science and engineering 2012年第1期2卷 38-43页

作者： elisa Julianti Ridwansyah era Yusraini Department of Food Science and Technology Faculty of Agriculture University of Sumatera Utara Medan 20155 Indonesia

An experiment retail film packaging system was used to compare the atmospheric composition within sealed packs containing barangan banana fruits. This research was done in order to study the effect of packaging films with different permeability properties on the physicochemicalproperties of barangan banana during storage at room temperature （28 ± 2 °C） and at 15 °C. The films used were 0.09 mm low density pol.ethylene （lDPe）, 0.04 mm polypropylene and 0.057 mm lDPe compared with unwrapped fruits as control. Barangan bananas were evaluated each 5 days intervals for changes in moisture content, total sugars, vitamin C, hardness and color. Unwrapped barangan bananas were overripe and soft after 15 days at both temperature conditions. Sealed packages especially using lDPe at 15 °C delayed the development of the yellow color of banana until 20 days of storage and had the lowest weight loss.

关键词： Modified atmosphere packaging barangan banana film plastic postharvest.

Opposite Interplay Between the Canonical WNT/β-Catenin Pathway and PPAR gamma： A Potential Therapeutic Target in Gliomas

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Neuroscience Bul.etin 2018年第3期34卷 573-588页

作者： AlexANDre Vall.e Yves lecarpentier Rémy Guil.evin Jean-Noёl Vall.e laboratory of Mathematics and Applications Unites Mixtes de Recherche (UMR) Centre National de la Recherche Scientifique (CNRS) 7348 University of Poitiers PoitiersFrance Delegation a la Recherche Clinique et a l'Innovation (DRCI) Hopital Foch Suresnes France Centre de Recherche Clinique Grand Hopital de l'EstFrancilien Meaux France DACTIM UMR CNRS 7348 University of Poitiers et CHU de Poitiers Poitiers France CHU Amiens Picardie University of Picardie Jules VerneAmiens France

In gliomas, the canonical Wingless/Int（WNT）/b-catenin pathway is increased while peroxisome proliferator-activated receptor gamma（PPAR-c） is *** two systems act in an opposite manner. This review focuses on the interplay between WNT/b-catenin signaling and PPAR-c and their metabolic implications as potential therapeutic target in gliomas. Activation of the WNT/bcatenin pathway stimulates the transcription of genes invol.ed in proliferation, invasion, nucleotide synthesis,tumor growth, and angiogenesis. Activation of PPAR-c agonists inhibits various signaling pathways such as the JAK/STAT, WNT/b-catenin, and PI3 K/Akt pathways,which reduces tumor growth, cell proliferation, cell invasiveness, and angiogenesis. Nonsteroidal anti-inflammatory drugs, curcumin, antipsychotic drugs, adiponectin,and sulforaphane downregulate the WNT/b-catenin pathway through the upregulation of PPAR-c and thus appear to provide an interesting therapeutic approach for ***（TMZ） is an antiangiogenic agent. The downstream action of this opposite interplay may explain the TMZ-resistance often reported in gliomas.

关键词： WNT/beta-catenin pathway PPAR gamma Glioma STAT3 pathway PI3K/Akt pathway NSAID Curcumin

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Neural Network-Based Second Order Reliability Method(NNBSORM)for laminated Composite Plates in Free Vibration

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Computer Modeling in engineering & Sciences 2018年第4期115卷 105-129页

作者： Mena e.Tawfik Peter l.Bishay edward e.Sadek Aerospace engineering Department Faculty of EngineeringCairo UniversityEgypt Mechanical and Aerospace engineering Department Rutgersthe State University of New JerseyNew BrunswickNJUSA Mechanical.engineering Department College of Engineering and Computer ScienceCalifornia State UniversityNorthridgeCAUSA.

Monte Carlo Simulations(MCS),commonly used for reliability analysis,require a large amount of data points to obtain acceptable accuracy,even if the Subset Simulation with Importance Sampling(SS/IS)methods are *** Second Order Reliability Method(SORM)has proved to be an excel.ent rapid tool in the stochastic analysis of laminated composite structures,when compared to the slower MCS ***,SORM requires differentiating the performance function with respect to each of the random variables invol.ed in the *** most suitable approach to do this is to use a symbolic sol.er,which renders the simulations very slow,although still faster than ***,the inability to obtain the derivative of the performance function with respect to some parameters,such as ply thickness,limits the capabilities of the classical *** this work,a Neural Network-Based Second Order Reliability Method(NNBSORM)is developed to replace the finite element algorithm in the stochastic analysis of laminated composite plates in free *** of the ability to obtain expressions for the first and second derivatives of the NN system outputs with respect to any of its inputs,such as material properties,ply thicknesses and orientation angles,the need for using a symbolic sol.er to calculate the derivatives of the performance function no longer *** proposed approach is accordingly much faster,and easily allows for the consideration of ply thickness *** present analysis showed that dealing with ply thicknesses as random variables results in 37%increase in the laminate’s probability of failure.

关键词： Reliability analysis artificial neural network composite laminates subset simulation importance sampling Monte Carlo

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风对柔软茎植物冠层光谱反射率的影响

南京气象学院学报 1990年第2期13卷 213-220页

作者：谈红宝 Hipps l.e 杨海鹰美国犹他州立大学河南省气象局科研所

文章对风导致的苜蓿冠层光谱反射率的变化进行了较细致的分析。分析所用的光谱反射率的取样速度平均为1.5赫。观测表明,大多数情况下苜蓿冠层的光谱反射率有风时比静稳条件下低。偏离的大小依波段而异。相对偏离大于3%的概率分别为:TMA... 详细信息

文章对风导致的苜蓿冠层光谱反射率的变化进行了较细致的分析。分析所用的光谱反射率的取样速度平均为1.5赫。观测表明,大多数情况下苜蓿冠层的光谱反射率有风时比静稳条件下低。偏离的大小依波段而异。相对偏离大于3%的概率分别为:TMA和TMB波段80%;TMC波段100%;TMD波段60%。风影响冠层反射率的机制是复杂的,不能用简单的统计方法如求平均值或中值消除。常用的亮度、绿度、红度和黄度等植被指数对风敏感,不宜在多风地区使用。因此建议在多风地区使用标准差植被指数。

关键词：风植物冠层光谱反射率

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