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91.
拱坝的智能优化辅助设计系统:ADIOCAD 总被引:3,自引:0,他引:3
笔者把专家系统。优化方法和计算机辅助设计三者熔为一体,建立了一个拱坝体形设计的集成系统-ADIOCAD,利用它可以选择拱坝的类型,坝轴线和坝的体形,求出给定条件下的最佳方案,并自动输出设计图纸,数据和设计报告,显著地提高了拱坝体形设计的效率和水平。 相似文献
92.
Yisheng Chen Xueming Xu Baocai Xu Zhengyu Jin Ruixin Lim Mohanad Bashari Na Yang 《European Food Research and Technology》2010,231(5):719-726
This study highlights the microwave-assisted biosynthesis of glycerol monolaurate catalyzed by Novozym 435 in reverse microemulsion
system dispersed by Aerosol-OT. Optimization of key parameters including catalyst/surfactant loading and temperature showed
that under microwave irradiation, 125.9 mol L−1 (36 wt%) of glycerol monolaurate was achieved within 30 min, which had improved 150% compared with that of water bath under
the same conditions (60 °C, 1 wt% enzyme, 5 wt% AOT). Also, a synergistic effect of microwave irradiation and Aerosol-OT on
reaction and a decline of optimum temperature (from 70 to 60 °C) were observed in comparison with traditional heating. More
importantly, further comparative studies on morphology and chemicophysical profiles of reaction system heated by different
thermal modes revealed the following: (1) due to the volumetric and selective heating character of molecular heating, superiorly
larger interface of reaction system was formed under microwave irradiation, directly accelerating the reaction course investigated;
and (2) microwave irradiation more favored a less compact state of enzyme. And faster mobilities of lid structure of enzyme
were evident under microwave irradiation. This enhancement might facilitate the transition of conformational states, which
is of key importance for the activation of bioactivity of Novozym 435. Moreover, the stepwise changes in steady-state fluorescent
profiles demonstrated that the thermal-induced variation was not two-state transition but involves intermediate states, which
was further supported by activity measurements reflected in glycerol monolaurate yield. 相似文献
93.
94.
城市水系统控制与规划原理 总被引:11,自引:1,他引:10
城市水资源的开发利用和保护涉及自然科学、社会科学和工程技术的许多领域,是一项非常复杂的系统工程。本文试图以系统科学理论为指导,构建城市水系统的理论框架,对城市水系统的内涵、要素、结构、功能和特征等进行分析,对城市水系统控制的依据、途径、类型和战略等进行探讨,并提出了加强城市水系统规划的建议。 相似文献
95.
Swaminathan J Krishnan A Gandour JT Xu Y 《IEEE transactions on bio-medical engineering》2008,55(1):281-287
This paper presents a new application of the dynamic iterated rippled noise (IRN) algorithm by generating dynamic pitch contours representative of those that occur in natural speech in the context of EEG and the frequency following response (FFR). Besides IRN steady state and linear rising stimuli, curvilinear rising stimuli were modeled after pitch contours of natural productions of Mandarin Tone 2. Electrophysiological data on pitch representation at the level of the brainstem, as reflected in FFR, were evaluated for all stimuli, static or dynamic. Autocorrelation peaks were observed corresponding to the fundamental period (tau) as well as spectral bands at the fundamental and its harmonics for both a low and a high iteration step. At the higher iteration step, both spectral and temporal FFR representations were more robust, indicating that both acoustic properties may be utilized for pitch extraction at the level of the brainstem. By applying curvilinear IRN stimuli to elicit FFRs, we can evaluate the effects of temporal degradation on 1) the neural representation of linguistically-relevant pitch features in a target population (e.g., cochlear implant) and 2) the efficacy of signal processing schemes in conventional hearing aids and cochlear implants to recover these features. 相似文献
96.
Xianjing Jia Yunfeng Yan A. Basak Kayitmazer Yongsheng Li Yisheng Xu 《Advanced functional materials》2021,31(32):2100452
Photothermal-chemotherapeutic nanoparticles (NPs) are attracting increasing attention and becoming more widely used for cancer therapy in the clinic due to their noninvasiveness, notable tissue penetration abilities, and low systemic adverse effects. However, functional ligands are conventionally modified onto photothermal NPs to well stabilize the inorganic particles suffering from complex chemical modifications, low productivity, and batch-to-batch inconsistencies, and thus significantly restricting their clinical applications. Herein, flash nanoprecipitation (FNP) is taken advantage of to afford rapid and uniform mixing for generating local supersaturated CuS clusters for small and highly stable CuS NPs effectively stabilized by polyacrylic acid through a continuous strategy. It greatly reduces the complexity for CuS NPs synthesis and functionalization in a facile intensified mixing process. These as-synthesized particles are high-drug loading, scalable, and most importantly, it is easy to control their sizes and charges through external conditions. Toxicity and tumor inhibition experiments confirm the high cell toxicity and good suppression of tumor growth under near-infrared irradiation indicating a promising prospect of FNP in the large-scale and continuous yielding of highly stable and high-performing photothermal-chemotherapeutic NPs for cancer therapy. 相似文献
97.
A class of multi‐input multi‐output (MIMO) block lower‐triangular systems are considered with the dynamic and static uncertainties related to the states of the former subsystems. A design procedure of robust tracking controller is presented, which avoids the problem of the “explosion of complexity” and can be implemented very simply. The closed‐loop system possesses robust properties that, 1) all signals involved are semi‐global uniformly ultimately bounded for bounded differentiable reference inputs; 2) for given initial tracking errors and uncertainty boundary, controller parameters can be found to guarantee that the tracking errors can be smaller than a specific positive constant after a limited time. Two numerical instances are given at last. 相似文献
98.
A robust control approach is presented for vertical manoeuvring helicopters with aerodynamics acting on the main rotor. An induced inflow observer is applied which only requires the measured values of the vertical accelerator in the body frame. The controller consists of three parts: a feedback linearisation controller, a nominal controller and a robust compensator. Feedback linearisation is applied to decouple the vertical motion dynamics and the rotor speed dynamics; the nominal controller aims to achieve desired performances for the nominal system without external disturbances or uncertainties; and the robust compensator is designed to restrain the effect of the external disturbance and the uncertainties. It is proven that all the states involved are bounded and the tracking error of the actual system can converge into an arbitrary specified boundary in a finite time for any given initial state. The results of outdoor flight experiments show that the robust tracking performances are consistent with the theory analysis conclusions. 相似文献
99.
100.
海表面盐度遥感是海洋遥感研究的重要内容之一。针对大气对海表面盐度遥感的影响,根据大气辐射传输理论,对大气影响进行仿真分析及修正,进而通过神经网络模型反演了海表面盐度。研究结果表明:大气对海表面盐度遥感存在一定的影响,需进行校正;当大气温度和压强精度分别达到2℃和10 hPa时,可以去除大气影响;训练样本集选取数量的不同将对神经网络反演精度造成一定的影响;SMAP卫星海表面盐度遥感反演结果相对误差较小,残差基本集中在0.6以内,但在盐度值低于34.4‰的区域误差较大。 相似文献