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41.
Hwansoo Lee Dongwon Lim Hyerin Kim Andrew P. Ciganek 《Behaviour & Information Technology》2015,34(1):45-56
Many e-commerce companies collect users’ personal data for marketing purposes despite privacy concerns. Information-collecting companies often offer a monetary reward to users to alleviate privacy concerns and ease the collection of personal information. This study focused on the negative effects of monetary rewards on both information privacy concerns (IPC) and information disclosure. A survey approach was used to collect data and 370 final responses were analysed using a two-way analysis of variance and a binomial logistic regression model. The results show that monetary rewards increase IPC when an information-collecting company requires sensitive information. Additional results indicate that building trust is a more effective way of collecting personal data. This study identifies how organisations can best execute information-collection activities and contributes additional insights for academia and practitioners. 相似文献
42.
A new matching cost computation method based on nonsubsampled contourlet transform (NSCT) for stereo image matching is proposed in this paper. Firstly, stereo image is decomposed into high frequency sub-band images at different scales and along different directions by NSCT. Secondly, by utilizing coefficients in high frequency domain and grayscales in RGB color space, the computation model of weighted matching cost between two pixels is designed based on the gestalt laws. Lastly, two types of experiments are carried out with standard stereopairs in the Middlebury benchmark. One of the experiments is to confirm optimum values of NSCT scale and direction parameters, and the other is to compare proposed matching cost with nine known matching costs. Experimental results show that the optimum values of scale and direction parameters are respectively 2 and 3, and the matching accuracy of the proposed matching cost is twice higher than that of traditional NCC cost. 相似文献
43.
为解决依赖装维上门鉴别光网络单元故障带来的不便,可以从机器视觉入手实现自动化故障识别。近年,ImageNet挑战赛的成功推动了物体识别技术的跨越式发展,特别是基于卷积的深度学习技术在视觉识别方面已经达到人类水平,为光网络单元故障的自动识别提供了技术基础。文章对识别光网络单元的工作状态进行了研究,将设备工作状态分为7个场景,提出了利用手机APP采集图片识别故障的解决方案并投入了实际生产;重点阐述了深度学习模块的设计与实现,提出一种通过算法整合的方式综合运用物体检测和图像分类算法,分3阶段逐步求精,解决了图片过滤,光网络单元型号和状态识别等问题,实现了基于计算机视觉自动识别光网络单元故障。从数据上看产品的端到端准确率超过84%,识别速度达到10 FPS,月均提供服务超过1万人次,在减少用户等待的同时节约了人力资源。 相似文献
44.
45.
Nutritional warnings are rapidly gaining relevance, particularly in the region of the Americas, as a front-of-package nutrition labelling scheme that facilitate the identification of products with high content of nutrients associated with non-communicable diseases (NCDs). Several graphic designs are being developed as countries discuss the implementation of nutritional warnings, which makes it necessary to develop research to evaluate their efficacy. In this context, the aim of the present work was to compare the efficacy of a series of nutritional warnings that are being considered by Brazilian national authorities for the country with two of the most studied schemes: the guidelines daily amounts (GDA) and the traffic light system. Two studies were conducted. In the first one, visual search was conducted with 62 participants to evaluate the time needed by them to identify the schemes on food labels and to identify whether a product had high nutrient content. In the second study, an online survey with 1932 participants was used to evaluate their ability to use FOP nutrition labelling schemes to correctly identify the most healthful product in a set, as well as high nutrient content in a product. In addition, the influence of FOP nutrition labelling schemes on perceived healthfulness was evaluated. Finally, consumers’ perception of the schemes was gathered using an open-ended question. Results confirmed the advantages of nutritional warnings compared to the GDA and the traffic-light system to facilitate the identification of products with high content of nutrients associated with NCDs. In addition, the use of familiar signs frequently used to convey a ‘warning message’ outperformed other unfamiliar signs in terms of their ability to facilitate the interpretation of nutrition information. Regarding colour, black signs tended to required significantly less time to be detected when included on colour food labels compared to red signs. 相似文献
46.
Ali Mohamed 《Journal of Modern Optics》2019,66(13):1392-1407
Anisoplanatic electromagnetic (EM) propagation across a turbulent atmosphere has been recently examined for an unmodulated carrier propagating over an image-bearing transparency through optical lensing, and for the embedded information inside a carrier recovered using heterodyning and digital demodulation. Carrier modulation yielded better recovery than simple lens-based imaging. A possible mitigation strategy is proposed whereby the image information is encrypted on an RF chaotic carrier, thereafter secondarily embedded onto an optical carrier. Results based on the modified von Karman (MVKS) and the Hufnagel-Valley (H-V) models showed that the signal/image recovery under turbulence is improved compared with non-chaotic propagation. The case of time-varying/dynamic images is also taken up; it is demonstrated via cross-correlation products that turbulence is mitigated by the use of chaotic carrier encryption. Overall, transmission via chaos offers mitigation against distortions due to turbulence along with the security feature inherent via the chaos keys which prevent signal recovery without key-matching. 相似文献
47.
针对基于规则和统计的传统中文简历解析方法效率低、成本高、泛化能力差的缺点,提出一种基于特征融合的中文简历解析方法,即级联Word2Vec生成的词向量和用BLSTM(Bidirectional Long Short-Term Memory)建模字序列生成的词向量,然后再结合BLSTM和CRF(Conditional Random Fields)对中文简历进行解析(BLSTM-CRF)。为了提高中文简历解析的效率,级联包含字序列信息的词向量和用Word2Vec生成的词向量,融合成一个新的词向量表示;再由BLSTM强大的学习能力融合词的上下文信息,输出所有可能标签序列的分值给CRF层;再由CRF引入标签之间约束关系求解最优序列。利用梯度下降算法训练神经网络,使用预先训练的词向量和Dropout优化神经网络,最终完成对中文简历的解析工作。实验结果表明,所提的特征融合方法优于传统的简历解析方法。 相似文献
48.
如今我国信息化技术全面发展,尤其对于工程测量工作领域来讲,不管是在工程建设和管理方面都产生不小的支撑引导效用。由此,笔者具体结合如今工程建设信息化测绘核心任何以及设备布置细节,进行结构整体安全管理周期和周边地理空间信息技术发展能效整理解析,试图将工程测量最新发展机遇和技术挑战问题处理完全。希望能够借此为日后一定时期范围内相关工程测量规划主体提供合理指导性建议内容,最终为我国各类工程事业可持续发展前景绽放奠定深刻适应基础。 相似文献
49.
Simulating the psychological experience of human vision,a road extraction model based on the format tower is proposed to extract the road in the high resolution remote sensing image from the perspective of morphology.Firstly,based on the spectral and texture information,the suspected road targets are extracted by using segmentation technology.Then these targets are classified according to their reliability and extract the road targets for each category.Finally,three types of identified road information are verified and merged,and the continuous smooth road extraction results are obtained.Experiments on real high resolution images show that the results are consistent with the visual perception of the human eye,and the overall classification accuracy is higher,indicating that the algorithm is effective and feasible and has good use value. 相似文献
50.
Haibo Zhang Guohua Geng Kang Li Cheng Liu Yuqing Hou 《Journal of Modern Optics》2018,65(20):2278-2289
Cone-beam X-ray luminescence computed tomography (CB-XLCT) is an attractive hybrid imaging modality, and it has the potential of monitoring the metabolic processes of nanophosphors-based drugs in vivo. However, the XLCT imaging suffers from a severe ill-posed problem. In this work, a sparse nonconvex Lp (0?p?1) regularization was utilized for the efficient reconstruction for early detection of small tumour in CB-XLCT imaging. Specifically, we transformed the non-convex optimization problem into an iteratively reweighted scheme based on the L1 regularization. Further, an iteratively reweighted split augmented lagrangian shrinkage algorithm (IRW_SALSA-Lp) was proposed to efficiently solve the non-convex Lp (0?p?1) model. We studied eight different non-convex p-values (1/16, 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, 7/8) in both 3D digital mouse experiments and in vivo experiments. The results demonstrate that the proposed non-convex methods outperform L2 and L1 regularization in accurately recovering sparse targets in CB-XLCT. And among all the non-convex p-values, our Lp(1/4?p?1/2) methods give the best performance. 相似文献