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Non-maximum suppression (NMS) plays a key role in many modern object detectors. It is responsible to remove detection boxes that cover the same object. NMS greedily selects the detection box with maximum score; other detection boxes are suppressed when the degree of overlap between these detection boxes and the selected box exceeds a predefined threshold. Such a strategy easily retain some false positives, and it limits the ability of NMS to perceive nearby objects in cluttered scenes. This paper proposes an effective method combining harmony search algorithm and NMS to alleviate this problem. This method regards the task of NMS as a combination optimization problem. It seeks final detection boxes under the guidance of an objective function. NMS is applied to each harmony to remove imprecise detection boxes, and the remaining boxes are used to calculate the fitness value. The remaining detection boxes in a harmony with highest fitness value are chosen as the final detection results. The standard Pattern Analysis, Statistical Modeling and Computational Learning Visual Object Classes dataset and the Microsoft Common Objects in Context dataset are used in all of the experiments. The proposed method is applied to two popular detection networks, namely Faster Region-based Convolutional Neural Networks and Region-based Fully Convolutional Networks. The experimental results show that the proposed method improves the average precision of these two detection networks. Moreover, the location performance and average recall of these two detectors are also improved. 相似文献
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《中国稀土学报(英文版)》2022,40(6):981-987
Based on the new process named “Combination Method” for metallurgy and separation of Baotou mixed rare earth concentrate (BMREC), the aim of this paper is to clearly elucidate the phase change behavior of BMREC without additives during oxidative roasting at 450–800 °C. The results indicate that the bastnaesite in BMREC is decomposed at 450–550 °C, the weight loss is about 10.3 wt%, and the activation energy (E) is 144 kJ/mol. The bastnaesite in BMREC is decomposed into rare earth fluoride, rare earth oxides (La2O3, Ce7O12, Pr6O11 and Nd2O3), and CO2, particularly, with the increase of roasting temperature, bastnaesite in BMREC is more completely decomposed into LaF3, which causes a decrease in leaching rate of La during the HCl leaching process. Additionally, the maximum cerium oxidation efficiency reaches about 60 wt% when the roasting temperature is equal to or above 500 °C, and the oxidation reaction rate of cerium increases with the increasing roasting temperature. 相似文献
4.
荷兰画家维米尔在多幅作品中使用了画中画的创作方法,对画作的最终呈现起到了从形式和到意义的多重作用。本文尝试发现和进入维米尔画中画的多种形式,探究其设置画中画的思考原点,以及讨论这样设置达成的效果。 相似文献
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If all components in a nanoindentation system are well calibrated and a reference material has unique hardness, H and reduced modulus, Er independent of the indentation depths, the load, L and the penetration depth, h in the indentation loading curve of the reference material can be correlated by L=Kh2. Here the constant K is expressed by H, Er and indenter geometry constants. By using H and Er of a fused silica and the Berkovich geometry, an analytical expression for the indentation loading curve could be derived. To compare with this analytical loading curve, experimental indentation data were measured with two commercial nanoindenters. The experimental loading curves shifted leftward or rightward from the analytical loading curve and this depth deviation was attributed to improper calibration of the nanoindenters. Quantitative calibrations of frame compliance and indenter bluntness were tried for the raw nanoindentation data and this resulted in consistent nanoindentation data regardless of the used nanoindenters. 相似文献
6.
The Food Neophobia Scale (FNS) measures reluctance to try novel foods. In describing foods, the term complexity is not well defined. The objective of this work was to assess the acceptability of familiar and novel foods, with varying levels of flavor complexity in both salty and sweet foods, by food neophobics and neophilics and to assess the effect of expectation (frame-of-reference effect) and familiarity on the acceptability of foods. FNS was administered to 864 subjects, who were classified to neophobic, or neophilic based on their FNS scores. Experiment 1, which was replicated twice, focused on four familiar foods, prepared in two versions, an original version and a more flavorful version. Subjects rated foods on complexity, acceptability and expectation. Neophilics gave significantly higher acceptability ratings to complex foods than bland foods and vice versa for neophobics. The different versions of foods did not always meet panelists’ flavor expectations. Experiment 2 included eight commercial foods, four salty and four sweet, with two novel and two familiar foods used within each taste category/quality. One of the foods within the familiar or novel pairs was expected to be flavorful (e.g. chili is typically served as spicy) and the other expected to be bland. Subjects rated foods on complexity, acceptability, familiarity and expectation. Six out of the eight flavorful versions of foods were chosen by subjects as more complex. Significant factors were taste quality, novelty, expectation, and familiarity (p < 0.05). Overall, neophilics were more accepting of novel foods than neophobics. The significant interaction between expectation and neophobia suggests that neophobics and neophilics may have different expectations of foods. Although neophobia × complexity was not significant, the neophobics’ acceptability ratings for bland versions were higher than for the flavorful versions. 相似文献
7.
An innovative prediction method for the combination of failure modes of an arch bridge is proposed for its probabilistic risk assessment and is compared with the conventional system reliability analysis method. The suggested method reveals various combinations of failure modes in significantly reduced time and efforts in comparison to the previous permutation method or the conventional system reliability analysis method. Additionally, the suggested method can be used for the verification of the system reliability with more specific predictions of the failure modes.Component reliabilities of girders have been evaluated by using response surfaces of the design variables at the selected critical sections, i.e. the maximum shear and negative moment locations. Response Surface Method (RSM) is successfully applied for the reliability analyses of complex structure with relatively small probability of failure. Previous methods such as Monte Carlo Simulations or First Order Second Moment method cannot easily calculate the derivative terms of implicit limit state functions. Hence, the target bridge system is modeled as a series-connection system for the analysis of its system reliability. The upper and lower bound of the probabilities of failure for the structural system have been evaluated and are compared with the suggested prediction method for all possible combination of failure modes. 相似文献
8.
随着计算机的应用 ,很多结构设计人员都甩掉了图板 ,采用了高效、准确、快捷的专业软件进行结构计算并绘图 ,PK-PM结构设计软件是其中应用较多的一种 ,本文介绍了 PK-PM使用中的一些经验及技巧 相似文献
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城乡一体化与乡村城市化双轨制探讨 总被引:7,自引:0,他引:7
对城乡一体化与乡村城市化进行探讨,提出二者关系密切又互为区别,其中小城镇在城乡一体化中起着特殊的作用,指出中国国情下的城市化道路应推行乡村城市化与城乡一体化双轨、同步的机制与做法,明确户籍制度改革是城乡一体化的先决条件。 相似文献