基于双滑动窗口的云服务可信评估

随着云计算的不断发展, 越来越多的云服务商利用云平台提供服务, 供云用户进行使用. 由于云平台无法得知云服务的配置和实现, 所以会产生信任缺失问题. 针对这个问题, 国内外提出了各种方法评估云服务的可信度, 但都较少的考虑了评价的客观性问题. 本文提出环境指标的概念, 使用滑动窗口结合主客观评价的方式对云服务进行可信评估, 并通过实验证明该评估方法提高了云服务可信评估的准确性.     

泾河流域水沙联合分布特征分析及其不确定性评估

径流与泥沙是非独立的二维随机变量,若要对流域实现水沙并举的科学管理方案,开展水沙联合概率分析显得尤为必要。而在联合概率分析中,水沙样本系列容量一般较小,使得联合设计值估计具有不确定性。以泾河流域为例,本文提出基于蒙特卡洛法的两变量联合设计值不确定性量化方法。该方法基于Copula函数建立水沙联合分布模型,推求两变量联合设计值的最可能组合模式,利用蒙特卡洛抽样法分析样本不确定性对水沙联合设计值的影响,计算两变量设计值置信区间。结果表明,OR重现期为20年的情况下,联合设计值95%二元置信区间表现出较大的不确定性,对流域工程设计值的确定提出了巨大挑战,且随着重现期水平的增加,联合设计值的不确定性随之增加。     

城市湖泊生态修复的水质响应研究

生态修复对遏制城市湖泊生态系统的退化意义重大,寻找一种有效且简单的生态修复效果预测方法有利于进一步推动湖泊修复研究的发展。利用综合污染指数法、基于专家调查法的湖泊污染物浓度确定方法及水质提升贡献度分析了生态修复的水质响应,并采用基于污染负荷平衡的水质模型预测了生态修复措施作用下的潜龙渠水质。结果表明:4种污染物浓度均有下降,潜龙渠水质提升显著,但各污染物对不同修复措施的响应程度不同,COD的浓度控制需要污染源控制与修复净化的共同支撑,TN对各项措施的敏感性接近,TP、NH_3—N分别对污染源控制、生态补水敏感性最高。情景预测表明,依据水质响应关系制定的生态修复方案,能够稳定保持潜龙渠的生态修复效果。     

基于Bloom过滤和分块的组合指纹模板保护算法

针对现有的组合指纹模板保护方法存在的认证性较差,导致检索错误率较高的问题,提出了一种基于组合指纹的Bloom过滤和分块的模板保护算法。该算法通过对原有的组合指纹模板进行MCC编码,再分块应用Bloom过滤器进行过滤,形成新的指纹模板。有效地提高了指纹模板的认证性,降低了指纹检索恢复时的错误率,提高了匹配的准确率。通过实验仿真与结果对比表明,该算法在保证了指纹模板私密性的同时,可以有效地提高指纹进行组合构成模板时所下降的认证性,使其在指纹匹配过程中的匹配时错误率降低,提高了指纹匹配的准确性。     

开闭环结合的水肥混灌系统

研发了一种开环和闭环结合的水、液肥混灌的自动控制系统,系统基于无线传感网实现.在系统的闭环部分,节点采集各大棚土壤的湿度,并经路由中继后,传递至协调节点,协调节点根据土壤湿度信息,控制自动灌水.在开环部分,系统接收用户指令,获得目标棚、灌溉量、水液肥比例等信息,然后依此混配水和液肥并将其灌溉至目标棚.本系统开环、闭环无缝结合,且开环、闭环部分均可独立工作,另外系统将业务逻辑功能分散到不同节点,实现了分布式控制.系统有效提高了水、肥的利用率,造价低廉,具有较大的推广、应用价值.     

Water Depth Information Extraction with Multi-spectralRemote Sensing in Coral Reefs Region

Water depth inversion is of great important to coral reefs’ protection and engineering construction of the coral reef region.As the correlation between the remote sensing radiance and the water depth is a very well,so the band ratio transform and the linear combination transform were adopted to the water depth inversion around coral reefs.Based on the complex topography of coral reefs,these two algorithms were optimized for the water depth inversion.Finally,our experimental results show that the improved ratio transform was suitable for retrieving water depths among 3~5 m and 5~10 m.While none of the models that mentioned in this paper performed well in water depth of 5~10 m,the preliminary conclusion was that coral reefs’ special topographic caused it.     

基于DST-PCR5多目标自适应视觉跟踪方法

复杂场景下实现快速稳定地自适应跟踪是视觉领域亟需解决的课题之一, 利用目标的多特征信息进行高效融合是提升跟踪算法鲁棒性能的重要途径。本文首先基于DST(Dempster-Shafer Theory)和PCR5(Proportional Conflict Redistribution No.5)设计一种新的合并策略融合运动目标的颜色和纹理特征,其次在粒子滤波框架下建立复杂场景下的多目标自适应跟踪模型,最终实现了复杂场景下多特征信息融合的自适应视觉跟踪。实验结果及性能分析表明,该方法在不良的跟踪条件下,高冲突证据的自适应处理能力得到明显改善,有效提高了粒子的使用效率和跟踪的鲁棒性,可以较好实现复杂场景下准确、稳定地多目标跟踪。     

基于AR的国家开放大学计算机专业体验式教学软件的设计开发

AR是一种新型多媒体计算机技术,融模式识别技术、机器学习技术、多媒体现实技术、3D建模技术于一体,创建一个具有智能性、交互性、沉浸感的虚实结合的系统。计算机专业体验式教学软件的设计对AR技术的应用与传播提供了有力支持,能够根据实际需求创设一个装配式开发环境,对当前所使用的软件开发环境进行扩展与延伸,借助多种类型建模组件将软件开发过程直观地展现出来,无需购置或者构建大型应用环境,将虚拟世界与真实世界无缝链接,从而提高国家开放大学学生的学习效率。     

Facial micro-expression recognition based on accordion spatio-temporal representation and random forests

Micro-expressions are very brief involuntary facial expressions which appear on the face of humans when they unconsciously conceal an emotion. Creating a solution allowing an automatic recognition of the facial micro-expressions from video sequences has garnered increasing attention from experts across such different disciplines as computer science, security, and psychology. This paper offered a solution to facial micro-expressions recognition, based on accordion spatio-temporal representation and Random Forests. The proposed feature space, called “Uniform Local Binary Patterns on an Accordion 2D representation of sub-regions presented by a Pyramid of levels (LBPAccP^u2)”, exploits the effectiveness of uniform LBP patterns applied on an accordion representation of sub-regions at different sizes. Random Forests were used to select the most discriminating features and reduce the classification ambiguity of similar micro-expressions through a new proximity measure. The main objective of our paper was to demonstrate that the use of few features could be more efficient to produce a strong micro-expression recognition classifier that outperforms the approaches that rely on high dimensional features space. The experimental results across six micro-expression datasets show the effectiveness of the proposed solution with an accuracy rate that can reach 81.38% on CasmeII dataset. Compared to some famous competitive state-of-the-art approaches, the proposed solution proved its performance thanks to its accuracy rate as well as the number of features it uses.     

Nanogel Encapsulated Hydrogels As Advanced Wound Dressings for the Controlled Delivery of Antibiotics

Biocompatible and degradable dual-delivery gel systems based on hyperbranched dendritic−linear−dendritic copolymers (HBDLDs) is herein conceptualized and accomplished via thiol-ene click chemistry. The elasticity of the hydrogels is tunable by varying the lengths of PEG (2, 6, 10 kDa) or the dry weight percentages (20, 30, 40 wt%), and are found to range from 2–14.7 kPa, comparable to human skin. The co-delivery of antibiotics is achieved, where the hydrophilic drug novobiocin sodium salt (NB) is entrapped within the hydrophilic hydrogel, while the hydrophobic antibiotic ciprofloxacin (CIP) is encapsulated within the dendritic nanogels (DNGs) with hydrophobic cores (DNGs-CIP). The DNGs-CIP with drug loading capacity of 2.83 wt% are then physically entrapped within the hybrid hydrogels through UV curing. The hybrid hydrogels enable the quick release of NB and prolonged released of CIP. In vitro cell infection assays showed that the antibiotic-loaded hybrid hydrogels are able to treat bacterial infections with significant bacterial reduction. Hybrid hydrogel band aids are fabricated and exhibited better antibacterial activity compared with commercial antimicrobial band aids. Remarkably, most hydrogels and hybrid hydrogels show enhanced human dermal cell proliferation and could be degraded into non-toxic constituents, showing great promise as wound dressing materials.