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91.
92.
塑料管材用于干式地板供热、供冷的可行性研究 总被引:4,自引:0,他引:4
据塑料管材的力学性能,针对其应用于地板供热、供冷时应注意的问题,从塑料管材使用条件、管材的选择、管壁厚度的确定、地板结构、介质作用温度及供热、供冷运行方式等方面对塑料管材应用于供热、供冷的可行性进行了探讨,提出了一些相应措施和技术方案,并给出了实例。 相似文献
93.
Tiziana Margaria Zongyan Qiu Hongli Yang 《International Journal on Software Tools for Technology Transfer (STTT)》2014,16(4):335-337
Program verification and testing techniques are crucial in fruitfully analyzing and validating complex software systems. This is an active research area and has produced various promising techniques in the last decade. However, many challenges lie ahead. We review the research area and summarize six papers selected from the Sixth International Symposium on Theoretical Aspects of Software Engineering (TASE 2012). 相似文献
94.
Jie Sheng Wang Shuang Han Qiu Ping Guo 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2014,18(3):457-468
Conversion rate in the Polyvinylchloride (PVC) polymerizing process has a certain influence on the molecular weight of PVC, porosity, absorption rate of plasticizer, vinyl chloride monomer (VCM) residue and thermal stability. Therefore, a predictive model based on echo state networks (ESN) method optimized by the artificial fish swarm algorithm (AFSA) is proposed to predict the conversion velocity. Firstly, the hot balancing mechanisms of polymerizer and the influenced factors of convention rate of VCM are analyzed in details. Then the auxiliary variables of the predictive model kernel are selected by using the kernel principal component analysis method for reducing the model dimensionality. Thirdly, the structure parameters of the ESN are optimized by the AFSA to realize the nonlinear mapping between input and output variables of the discussed soft-sensor model. The artificial fish swarm behaviors, such as foraging, swarming, chasing, random, are introduced in details. Finally, simulation results show that the proposed model can significantly enhance the predictive accuracy and robustness of the technical index and satisfy the real-time control requirements of PVC polymerizing production process. 相似文献
95.
A new terrain‐inclination‐based localization technique is proposed in this paper to enable a robot to identify its three‐dimensional location relative to measurable terrain inclinations. Given a topographical map and a planned path, a robot‐terrain‐inclination model (RTI model) is extracted along the path on the terrain upon which the robot is operating. A particle filter is then used to fuse the measurement data with the robot motion based on the extracted RTI model for either a three‐wheeled or a four‐wheeled mobile robot. Experiments were carried out in four outdoor scenarios: one short path with different initial conditions and map resolution, another short path with different surface roughness and sensor accuracy, and two long paths with different types of rigid terrains and multiple loops. Experimental results show that the proposed method could achieve good localization performance on inclined outdoor terrains. 相似文献
96.
97.
Xipeng Pu Xuejian Liu † Fagui Qiu Liping Huang 《Journal of the American Ceramic Society》2004,87(7):1392-1394
A novel method has been developed for the fabrication of silicon nitride reticulated porous ceramics (RPCs) with regulated structure, using polyurethane sponge as the template. This technique includes two centrifuging steps. In the first stage, the polyurethane sponges are coated with thin slurry through high-speed centrifuging. After the slurry on sponges dried, a high-strength green body without filled cells is obtained. In the second stage, because of improved adhesion between the body and the slurry after the first coating, the body with uniformly thick strut is produced by recoating the as-prepared green body with thixotropic slurry and centrifuging again. The loading content of slurry and the pore diameter of the RPCs body greatly depend on the slurry viscosity in the process of recoating. The strut diameter and pore diameter of the RPCs are effectively optimized by modulating the slurry viscosity. 相似文献
98.
99.
Water-soluble single-walled carbon nanotubes (SWNTs) were synthesized by grafting poly(acrylamide) (PAM) from the surface of SWNT via reversible addition-fragmentation chain transfer (RAFT) polymerization. The RAFT agents were covalently attached to the SWNTs by functionalizing SWNTs with in situ generated diazonium compounds. The product was characterized by means of FT-IR, Raman, 1H NMR, TGA and TEM. The results showed that PAM chains had successfully grafted from SWNT by RAFT polymerization. The amount of PAM grown from SWNT increased with the polymerization time. The acrylamide conversion increased linearly with the polymerization time, indicating the “living” characteristics of the RAFT polymerization. TEM was utilized to image PAM-g-SWNT, showing relatively uniform polymer coatings present on the surface of individual, debundled nanotubes. 相似文献
100.
本文介绍了用一种再结晶技术制造高炖、超细Al_2O_3粉体的新方法。 将硫酸铝铵溶液(AA)滴入碳酸氢铵溶液(AHC),经过反应合成一种新的含铝化合物,碳酸氢铝铵(AACH),然后在高温下煅烧,生成超细Al_2O_3粉体。另外还采用了X射线,红外光谱,DTA,以及TEM等手段,研究了反应温度、浓度、PH值和老化条件等对生成物AACH和Al_2O_3的影响。 相似文献