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991.
In this paper we propose a novel deep spatial transformer convolutional neural network (Spatial Net) framework for the detection of salient and abnormal areas in images. The proposed method is general and has three main parts: (1) context information in the image is captured by using convolutional neural networks (CNN) to automatically learn high-level features; (2) to better adapt the CNN model to the saliency task, we redesign the feature sub-network structure to output a 6-dimensional transformation matrix for affine transformation based on the spatial transformer network. Several local features are extracted, which can effectively capture edge pixels in the salient area, meanwhile embedded into the above model to reduce the impact of highlighting background regions; (3) finally, areas of interest are detected by means of the linear combination of global and local feature information. Experimental results demonstrate that Spatial Nets obtain superior detection performance over state-of-the-art algorithms on two popular datasets, requiring less memory and computation to achieve high performance. 相似文献
992.
In this paper, the equivalent disturbance rejection (EDR) in QFT design methodology is proposed for dealing with sampled-data systems with time-delay. This EDR is mainly to overcome the non-minimum phase zero generated by the first order Pade' approximation of the time-delay factor. Due to plant parameter uncertainty, the analogue controller is to be designed so that the system response lies within permissible bounds. By approximate Z-transform, the analogue controller can be transformed directly into a digital one and then the analogue plant is transformed into the digital plant, with sampling time as a free parameter. By adjusting the sampling time, the uncertain sampled-data system can be stabilized. In comparison with other approaches, our design framework is much more systematic by using only algebraic manipulations and transparent enough to guide the designer to realize the physical controller for the plant with prescribed bounds on its parameters. 相似文献
993.
Stabilization of epoxidized soybean oil‐plasticized poly(vinyl chloride) blends via thermal curing with genistein
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In an effort to alleviate the well‐known toxicity effect of phthalate derivatives on human health, genistein (G) modified epoxidized soybean oil (ESBO) has been investigated as an alternative “green” plasticizer for poly(vinyl chloride) (PVC) with potential application in medical products. As evidenced by a single glass transition that shifts systematically with composition in conjunction with the melting point depression of G crystals, ESBO is not only a good plasticizer to PVC, but also miscible with G. Moreover, ESBO is an excellent compatibilizer to the immiscible PVC/G pair. Furthermore, PVC/ESBO/G ternary blends revealed complete miscibility in the amorphous state. Of particular interest is that ESBO‐plasticized PVC is thermally curable with G at elevated temperatures above 220 °C and affords relatively stable G modified ESBO‐plasticized PVC for blood contact medical applications such as blood bags and hemodialysis tubings. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46472. 相似文献
994.
用新思维设计自动充填包装生产流水线,解决了胶粘剂灌装难题,流水线主要由灌装体气缸阀总成,输送带,无级变速电动机,电器控制箱四部分构成。 相似文献
995.
Sha Wang Tian Li Chaoji Chen Weiqing Kong Shuze Zhu Jiaqi Dai Alfredo J. Diaz Emily Hitz Santiago D. Solares Teng Li Liangbing Hu 《Advanced functional materials》2018,28(24)
Cellulose nanofibrils are attractive as building blocks for advanced photonic, optoelectronic, microfluidic, and bio‐based devices ranging from transistors and solar cells to fluidic and biocompatible injectable devices. For the first time, an ultrastrong and ultratough cellulose film, which is composed of densely packed bacterial cellulose (BC) nanofibrils with hierarchical fibril alignments, is successfully demonstrated. The molecular level alignment stems from the intrinsic parallel orientation of crystalline cellulose molecules produced by Acetobacter xylinum. These aligned long‐chain cellulose molecules form subfibrils with a diameter of 2–4 nm, which are further aligned to form nanofibril bundles. The BC film yields a record‐high tensile strength (≈1.0 GPa) and toughness (≈25 MJ m?3). Being ultrastrong and ultratough, yet the BC film is also highly flexible and can be folded into desirable shapes. The BC film exhibits a controllable manner of alignment and is highly transparent with modulated optical properties, paving the way to enabling new functionalities in mechanical, electrical, fluidic, photonics, and biocompatible applications. 相似文献
996.
Meiling?WangEmail authorView authors OrcID profile Wenfeng?Bian Zhaochun?Jiang 《Polymer Bulletin》2017,74(10):4143-4151
According to the Weibull theory, the micropore sizes were used to analyze the stress intensity factor of carbon fiber monofilament crack tip stress field. Based on the analysis of carbon fiber monofilament and multifilament tensile strength, diameter and micropore size get the relationship between carbon fiber monofilament tensile strength and the pore radius by the Guinier principle and Griffith fracture theory, thus to estimate carbon fiber fracture toughness. The results show that this method can implement the estimation of fracture toughness on the basis without destroying the structure of the carbon fibers; the fracture toughness of T300 estimated by the average pore size was 1.34 MPa·m1/2, in accordance with data 1.25 and 1.32 MPa·m1/2 by producing defects, errors are 7.2 and 1.5%, respectively. 相似文献
997.
采用射频(RF)磁控溅射工艺于玻璃衬底沉积了镓钛 共掺杂氧化锌(GZO:Ti)半导体薄膜,研究了沉积 温度对薄膜微观结构和光学性质的影响。通过X射线衍射仪(XRD)和紫外分光光度计对其晶体 结构和透射光谱特 性进行表征,同时利用光谱拟合法获取了薄膜的光学常数。研究结果表明,所有薄膜均具备 六角纤锌矿结 构和c轴择优取向特性,沉积温度对薄膜的微结构参数、光学 常数和光学带隙具有明显调控作用,当沉积 温度为653K时,GZO:Ti薄膜的晶粒尺寸最大(82.12nm)、位错密度最低(1.48×10-4 nm-2) 、微应变最小(0.001)、可见光区平均透射 率 最高(82.06%)及光学带隙值最大(3.57eV )。 相似文献
998.
999.
Wanqun Chen Xiangyu Teng Dehong Huo Quanlong Wang 《The International Journal of Advanced Manufacturing Technology》2017,93(9-12):3005-3016
Micro milling, as a versatile micro machining process, is kinematically similar to conventional milling; however, it is significantly different from conventional milling with respect to chip formation mechanisms and uncut chip thickness modelling, due to the comparable size of the edge radius to the chip thickness, and the small per-tooth feeding. Considering tool runout and dynamic displacement between the tool and the workpiece, the contour of the workpiece left by previous tool paths is typically in a wavy form, and the wavy surface provides a feedback mechanism to cutting force generation because the instantaneous uncut chip thickness changes with both the vibration during the current tool path and the surface left by the previous tool paths. In this study, a more accurate uncut chip thickness model was established including the precise trochoidal trajectory of the cutting edge, tool runout and dynamic modulation caused by the machine tool system vibration. The dynamic regenerative effect is taken into account by considering the influence of all the previous cutting trajectories using numerical iteration; thus, the multiple time delays (MTD) are considered in this model. It is found that transient separation of the tool-workpiece occurring at a low feed per tooth, caused by MTD and the existing cutting force models, is no longer applicable when transient tool-workpiece separation occurs. Based on the proposed uncut chip thickness model, an improved cutting force model of micro milling is developed by full consideration of the ploughing effect and elastic recovery of the workpiece material. The proposed cutting force model is verified by micro end milling experiments, and the results show that the proposed model is capable of producing more accurate cutting force prediction than other existing models, particularly at small feed per tooth. 相似文献
1000.