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1.
Wonje Jang Junhyuk Hyun Jhonghyun An Minho Cho Euntai Kim 《IEEE/CAA Journal of Automatica Sinica》2022,9(1):187-204
The essential requirement for precise localization of a self-driving car is a lane-level map which includes road markings (RMs). Obviously, we can build the lane-level map by running a mobile mapping system (MMS) which is equipped with a high-end 3D LiDAR and a number of high-cost sensors. This approach, however, is highly expensive and ineffective since a single high-end MMS must visit every place for mapping. In this paper, a lane-level RM mapping system using a monocular camera is developed. The developed system can be considered as an alternative to expensive high-end MMS. The developed RM map includes the information of road lanes (RLs) and symbolic road markings (SRMs). First, to build a lane-level RM map, the RMs are segmented at pixel level through the deep learning network. The network is named RMNet. The segmented RMs are then gathered to build a lane-level RM map. Second, the lane-level map is improved through loop-closure detection and graph optimization. To train the RMNet and build a lane-level RM map, a new dataset named SeRM set is developed. The set is a large dataset for lane-level RM mapping and it includes a total of 25157 pixel-wise annotated images and 21000 position labeled images. Finally, the proposed lane-level map building method is applied to SeRM set and its validity is demonstrated through experimentation. 相似文献
2.
能源和化学品价格的快速上涨使得制浆工作者尤为关注如何降低纸浆漂白成本。本研究构建了纸浆漂白成本的在线计算模型,并应用于典型ECF漂白技术(D0EpPD1),同时系统分析了影响纸浆漂白成本的主要因素和该模型在漂白工艺条件优化过程中的应用效果。研究发现,化学品成本是影响漂白成本的最主要因素,其次是能源成本、废水处理成本、清水成本;化学品中ClO2用量对纸浆漂白成本的影响最大,其次是H2O2用量,NaOH用量影响最小;能源成本中蒸汽用量对纸浆漂白成本影响最大;而清水成本和废水处理成本影响最小;通过对化学品用量、漂白温度等漂白工艺条件的调整可降低纸浆漂白成本;该模型可实现对漂白工艺条件的优化或能源及化学品价格变化后纸浆漂白成本的在线预测,也是实现纸浆漂白系统全局优化、进一步降低漂白成本的基础。 相似文献
3.
针对轴承振动实时状态监控的需要,从符号动力学角度提出了符号聚合近似与Lempel-ziv复杂度(SAX-LZC)融合的振动监控参数。首先,以Logistic映射和Duffing方程为对象,从理论角度验证了SAX-LZC对动力学结构表征的准确性,并验证了该指标的抗噪能力和计算效率;其次,将SAX-LZC指标与信息熵、样本熵、多分段Lempel-ziv复杂度等动力学参数性能进行了综合对比;最后,从实验角度对轴承早期微弱异常进行了监测,并对轴承典型故障进行了特征提取。理论研究结果表明,SAX-LZC具有动力学结构表征准确、抗噪能力好、计算高效简洁等优点,克服了常规动力学参数工程应用能力弱的问题。实验研究结果表明,SAX-LZC对早期微弱异常有准确的监测,对不同种类故障具有较好的区分度,弥补了时域和频域对轴承微弱故障表征能力不足的缺陷,是一种轴承振动实时状态监控与故障特征提取的有效参数。 相似文献
4.
随着无源光网络的发展,光纤-无线网络能同时支持集中式云和边缘云计算技术,成为一种具有发展前景的网络结构。但是,现有的基于光纤-无线网络的任务协同计算卸载研究主要以最小化移动设备的能耗为目标,忽略了实时性高的任务的需求。针对实时性高的任务,提出了以最小化任务的总处理时间为目标的集中式云和边缘云协同计算卸载问题,并对其进行形式化描述。同时,通过将该问题归约为装箱问题,从而证明其为NP难解问题。提出一个启发式协同计算卸载算法,该算法通过比较不同卸载策略的任务处理时间,优先选择时间最短的任务卸载策略。同时,提出一个定制的遗传算法,获得一个更优的任务卸载策略。实验结果表明,与现有的算法相比,本文提出的启发式算法得到的任务卸载策略平均减少4.34%的任务总处理时间,而定制的遗传算法的卸载策略平均减少18.41%的任务总处理时间。同时,定制的遗传算法的卸载策略与本文提出的启发式算法相比平均减少14.49%的任务总处理时间。 相似文献
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随着经济的发展和市场竞争的加剧,企业必须能够快速且准确地满足市场和用户的各种需求。Web服务组合正是由于单个Web服务不能满足企业及用户的需求而产生的一种技术,而如何确保组合的正确性来实现服务增值是一个尚未完全解决的问题。针对此问题,提出了一种基于符号模型检测器NuSMV对Web服务组合进行验证的方法,并提出了基于消息会话的Web服务有限状态自动机的形式化定义。最后实例验证了Web服务组合交互的正确性和有无死锁状态现象,进一步证明了方法的可行性。 相似文献
7.
Colors can be characterized by three main attributes: hue, value, and saturation. But colors also exhibit other phenomenological qualities. In this study, we identify one such secondary attribute of color: perceived density. We discuss the prevalence of dense colors in Japan starting from the “48 Teas and 100 Mice” colors of the Edo period, and develop the concept of perceived density through this aspect of Japanese color preference. When vivid colors were forbidden to commoners during the Edo period, subtle variations of brownish and grayish colors were created. These colors with base tones were not salient, yet they looked dense. Muted colors with paradoxical richness are still common in Japan today. Japanese commodity design often uses muddy colors with white or gray undertones, and deep colors with black undertones. Together they form distinct groupings of relatively dense color. The perceived density of color corresponds to how dense and filled, or thin and airy a color appears. Colors of higher perceived density appear to be more packed and to have mass. Perceived density of color is unusual in that it does not have a monotonic relationship with one of the primary perceptual attributes. High apparent density is observed in a central region of an equi‐hue plane where value or saturation are at intermediate values. We consider two possible explanations of how high values of density can coincide with middling values of value and saturation: characteristics of the spectral reflectance curves, or the complexity of the neural signals that underlie the emergent property. 相似文献
8.
Bingbing JIANG 《Frontiers of Computer Science》2022,16(1):161809
López-Alt et al.(STOC12)put forward a primitive called multi-key fully homomorphic encryption(MKFHE),in which each involved party encrypts their own data using keys that are independently and randomly chosen whereby arbitrary computations can be performed on these encrypted data by a final collector.Subsequently,several superior schemes based on the standard assumption(LWE)were proposed.Most of these schemes were constructed by expanding a fresh GSW-ciphertext or BGV-ciphertext under a single key to a new same-type ciphertext of the same message under a combination of associated parties’keys.Therefore,the new ciphertext’s size grew more or less linearly with an increase in the number of parties.In this paper,we proposed a novel and simple scheme of MKFHE based on LWE without increasing the size of the ciphertext in the two non-collusion server model.In other words,each party first independently shares their own data between two servers and each server only needs a one-round communication with another to construct a ciphertext of the same plaintext under a sum of associated parties’keys.Our new ciphertext under multiple keys has the same size as that of the original one with only one-round communication between two servers.The communication complexity is O(kmlogq)-bit,where k is the number of input ciphertexts involved,m is the size of a GSW-ciphertext and q is a modulus.In conclusion,we proved that our scheme is CPA-secure against semi-honest adversaries. 相似文献
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10.
序贯模块法广泛应用于化工过程流程模拟。对于具有回路的化工过程,其计算顺序的确定是很重要的问题。本文针对有回路的焦炉气甲烷化流程进行了分析,确定了其模拟计算时的计算顺序,对焦炉气甲烷化流程的研究具有很好的参考价值。 相似文献