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81.
Handling occlusion is a very challenging problem in object detection. This paper presents a method of learning a hierarchical model for X-to-X occlusion-free object detection (e.g., car-to-car and person-to-person occlusions in our experiments). The proposed method is motivated by an intuitive coupling-and-decoupling strategy. In the learning stage, the pair of occluding X?s (e.g., car pairs or person pairs) is represented directly and jointly by a hierarchical And–Or directed acyclic graph (AOG) which accounts for the statistically significant co-occurrence (i.e., coupling). The structure and the parameters of the AOG are learned using the latent structural SVM (LSSVM) framework. In detection, a dynamic programming (DP) algorithm is utilized to find the best parse trees for all sliding windows with detection scores being greater than the learned threshold. Then, the two single X?s are decoupled from the declared detections of X-to-X occluding pairs together with some non-maximum suppression (NMS) post-processing. In experiments, our method is tested on both a roadside-car dataset collected by ourselves (which will be released with this paper) and two public person datasets, the MPII-2Person dataset and the TUD-Crossing dataset. Our method is compared with state-of-the-art deformable part-based methods, and obtains comparable or better detection performance.  相似文献   
82.
In this paper, we make use of biologically inspired selective attention to improve the efficiency and performance of object detection under clutter. At first, we propose a novel bottom-up attention model. We argue that heuristic feature selection based on bottom-up attention can stably select out invariant and discriminative features. With these selected features, performance of object detection can be improved apparently and stably. Then we propose a novel concept of saccade map based on bottom-up attention to simulate the saccade (eye movements) in vision. Sliding within saccade map to detect object can significantly reduce computational complexity and apparently improve performance because of the effective filtering for distracting information. With these ideas, we present a general framework for object detection through integrating bottom-up attention. Through evaluating on UIUC cars and Weizmann–Shotton horses we show state-of-the-art performance of our object detection model.  相似文献   
83.
DTPA-双(3,5-二甲氧基-4''''-氨基二苯乙烯)的合成   总被引:2,自引:0,他引:2  
以3,5-二甲氧基苄溴为起始原料,通过Witting-Hornor反应,再经Fe/HCl还原,合成了3,5-二甲氧基-4'-氨基二苯乙烯.再与DTPAA反应得到标题化合物,其结构经IR、MS、1HNMR、元素分析确证.  相似文献   
84.
上海地区不同商品粉煤灰水泥浆体的流变性能   总被引:1,自引:0,他引:1  
采集了上海地区不同种类,等级和加工方式的7种商品粉煤灰,测定了种各种粉煤灰水泥浆体的流变性能,研究了商品粉煤灰品质与掺量对浆体流变参数的影响,并分析了影响浆体流变性能的粉煤灰主要品质因素。  相似文献   
85.
A series of heterocyclically conjugated polymer–clay nanocomposite (PCN) materials that consisted of organic poly(3‐hexylthiophene) (P3HT) and inorganic montmorillonite (MMT) clay platelets were prepared by in situ oxidative polymerization with FeCl3 as an oxidant. The as‐synthesized PCN materials were characterized by Fourier transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (WAXRD), and transmission electron microscopy (TEM). The effects of the material composition on the anticorrosion, gas barrier, thermal stability, flammability, mechanical strength, and electrical conductivity properties of the P3HT and PCN materials were studied by electrochemical corrosion measurements, gas‐permeability analysis (GPA), thermogrametric analysis (TGA), limiting oxygen index (LOI) measurements, dynamic mechanical analysis (DMA), and a four‐point probe technique, respectively. The molecular weights of extracted and bulk P3HT were determined by gel permeation chromatography (GPC) with THF as an eluant. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3438–3446, 2004  相似文献   
86.
Blends of polyethylene terephthalate (PET) and ethylene‐ethyl acrylate‐maleic anhydride terpolymer (E‐EA‐MAH) were dynamically crosslinked in a one‐step extrusion process. An amine‐terminated glycol reacting with MAH moieties was used as the crosslinking agent. The effect of blend composition and dynamic crosslinking on the microstructure and mechanical properties were investigated. Blend ratios ranging from 80:20 to 20:80 PET/E‐EA‐MAH were studied. The region of phase inversion was located for uncrosslinked and dynamically crosslinked blends. The rheological characterization was also carried out for these blends in comparison with the neat materials. After dynamic crosslinking, the phase inversion is shifted from the 30–40% range to the 70–80% range of elastomer content. This shift is induced by the increase of viscosity and elasticity of the network formed. Dynamically crosslinked blends show significant improvements in impact strength but also exhibit a decrease in elongation at break.  相似文献   
87.
裴永中 《中国陶瓷》2006,42(8):45-46
着重论述写实人物瓷画创作要获得形神兼备的艺术效果,必须掌握的问题和运用的有效方法。  相似文献   
88.
如何使得一个不具备ABAP编程语言基础的财务用户能在SAP系统中快速有效地配置财务报表,并灵活定义输出格式,是许多实施SAP ERP系统的公司都会遇到的问题。本文介绍的财务模块报表定制功能旨在SAP ERP中构建一个可视化图形界面,在这个界面中定义报表、报表版本,以及每个版本的输出布局、报表行、报表列、报表单元格的取数逻辑等要素,使得用户在不使用编程工具的前提下实现报表的灵活定制。  相似文献   
89.
在氟化铝母液中添加氯化铝等可溶性铝盐,可有效地阻止钠,氟,铝间冰晶石固体物质的形成,从而达到防止氟化铝脱硅工艺中铝,氟的损耗,确保氟硅酸钠的产品质量,同时提高母液利用的经济效益。  相似文献   
90.
Rejection of nasturtium,Tropaeolum majus, by cabbage-reared larvae ofPieris rapae has been explained by the presence of feeding deterrents in the nastrutium foliage. Sensitivity to the deterrents develops as neonate larvae feed on cabbage. The most prominent deterrent compound, which is present in nasturtium at a concentration of 40 mg/100 g fresh leaves, was identified as chlorogenic acid. When neonate larvae were fed on a cabbage leaf treated with high concentrations of deterrent-containing extracts of nasturtium foliage, they remained insensitive to the deterrents, so they accepted nasturtium when transferred as second instars. When neonate larvae were reared on a cabbage leaf treated with 0.1 mg chlorogenic acid, ca. 35% of the second instars accepted nasturtium. Similar dietary exposure of neonates to the subunits of chlorogenic acid, caffeic acid and quinic, acid resulted in much less or no effect on the rejection behavior of second instars. The results suggest that the combined effects of specific chemical constituents of nasturtium can explain the rejection of this plant by larvae ofP. rapae, but if larvae are continuously exposed to these compounds immediately after hatching, they apparently become habituated to the feeding deterrents. The lack of activity of the subunits of chlorogenic acid suggests that specific structural features are necessary for a dietary constituent to cause such habituation or suppression of sensitivity development.  相似文献   
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