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991.
探讨公共设施环境陶艺形态的类型、表现手法及特点,指出公共设施中的环境陶艺形态设计要强调实用与审美、环境相统一。 相似文献
992.
A structural model for the cholesterol-phosphatidylcholine complexes in bilayer membranes 总被引:5,自引:0,他引:5
Ching-Hsien Huang 《Lipids》1977,12(4):348-356
Based on the structural properties of phospholipid and cholesterol molecules, and making use of the known structural and motional
effects of cholesterol and its analogs on phospholipid bilayers, a model for the cholesterol-phosphatidylcholine complex is
proposed. In this model, the 3β-hydroxyl group of cholesterol is assumed to engage in hydrogen bonding with the carbonyl oxygen
of the fatty acyl groups in phospholipids. Some specific configurations of the saturated and unsaturated fatty acyl chains
of the phospholipid are suggested to participate in van der Waals attractive interactions with the α and β surface of the
steroid nucleus. 相似文献
993.
We report the results of electron paramagnetic resonance studies of GdX (X=As, Sb, Bi, S, Se). The temperature dependence of the linewidth H and effective g-factorg
eff are discussed. Values for the Néel temperatureT
N are inferred from coincident anomalies in H andg
eff. In the cases of X=S and Se, our estimates ofT
N are significantly lower than theT
N inferred from static susceptibility measurements. A possible source of the discrepancy is discussed.Supported by the National Science Foundation Grant No. DMR-74-08033.Work performed under the auspices of the U.S. ERDA.Supported by the National Science Foundation. 相似文献
994.
本文介绍了一个图形用户接口管理系统——GUIDE-GKS系统中的用户接口描述方法,以及利用这些描述信息而进行的用户接口快速原型和自动生成技术。其中,基于用 户概念模型的思想,它提出了一种新的“引导式”描述技术,该技术使得接口设计者对系统的学习使用更为方便、简洁、有效,增强了接口描述过程的正确性保证,并易于导致好性能接口的开发。 相似文献
995.
Acoustic emission (AE) experiments have been performed on gas-saturated coal specimens under conventional triaxial compression. The AE characteristics were investigated for a methane gas flow through the coal specimen. One AE parameter, AE count, when normalized by the total count number was used to represent the damage evolution in the gassy coal. It is shown that this AE parameter is a reasonable indicator for damage occurring within the coal specimen since its envelope has almost the same shape as the complete stress–strain curve, except for a short time delay. In addition, the change in AE count is highly consistent with the change in coal permeability. Test results also show that methane containing coal emits a small number of AE events before entering the yield stage. AE activity gradually increases during the yield process up to the peak stress. The lowest permeability corresponds to the highest AE activity, implying failure will soon occur. An AE based constitutive model was constructed and the theoretical results agree well with those of experiments. 相似文献
996.
In this paper, the singular value decomposition (SVD) based identification and compensation of the hysteretic phenomenon in piezo actuators are addressed using a Preisach model. First, this paper presents an SVD-based least squares algorithm and a revision approach of the identification through updating the SVD. With the identified parameters and a log of the memory curve, a Preisach-based inversion compensator is constructed which is complemented with a feedback controller to address the inevitable and residual modeling errors. Experimental results are furnished for both the identification and compensation approaches. The Preisach-based feedforward controller significantly improves the tracking performance and reduces the root-mean-square (RMS) tracking error of a PID controller by 76.7% and 89% at 1 Hz and 25 Hz, respectively. With the proposed composite controller, the percent-RMS errors at 1 Hz and 25 Hz are reduced to 0.035% and 0.31%, respectively. 相似文献
997.
In recent years, some Chinese doctors have proposed a new concept, gallstone removal without gallbladder excision, along with transition of the medical model. As there is no specialized endoscope for gallstone removal without gallbladder excision, we designed and produced a new series of gallbladder endoscopes and accessories that have already been given a Chinese invention patent (No. ZL200810199041.2). The design of these gallbladder endoscopes was based on the anatomy and physiology of the gallbladder, characteristics of gallbladder disease, ergonomics, and industrial design. This series of gallbladder endoscopes underwent clinical trials in two hospitals appointed by the State Administration of Traditional Chinese Medicine. The clinical trials showed that surgeries of gallstones, gallbladder polyps, and cystic duct calculus could be smoothly performed with these products. In summary, this series of gallbladder endoscopes is safe, reliable, and effective for gallstone removal without gallbladder excision. This note comprehensively introduces the research and design of this series of gallbladder endoscopes. 相似文献
998.
基于Android的火车票实名检票系统设计 总被引:3,自引:0,他引:3
介绍了一种基于嵌入式平台的实名制检票手持终端的硬件构成和软件实现。采用了Android嵌入式操作系统,对火车票上QR二维码和二代身份证RFID系统采集到的数据进行提取、显示。同时通过WIFI,将采集到的数据与服务器数据进行比对。实际运行表明,系统运行稳定,可正确快速地识别出实名火车票的真伪,实现了系统设计的功能要求。 相似文献
999.
分析了TI公司的TMS320DM355的启动方式和NAND启动流程,使开发者能够根据实际需求改动DVSDK中的UBL与编译U-Boot,并排除开发过程中出现的错误。使开发者通过各种方式下载操作系统内核映像至DM355的Flsah,并建立NFS文件系统,从而建立一个完整的开发环境。 相似文献
1000.