EDGE MATCHING RATE BASED ON GENERALIZED ACREAGE FOR IMAGES REGISTRATION

This paper proposes an enhanced Edge Matching Rate (EMR) to gain good image regis-tration based on Generalized Acreage (GA). Traditional EMR considers only matched pixels sum without concerns of the cause of unmatched pixels and the relationship between matched pixels. The modified EMR introduces the new concept of generalized acreage to measure the overlaying parts between the target image and the model. It also defines similarity of local occlusion and of local dithering to measure interference degree. Not only edge points are considered but also non-edge points, occlusion, and dithering. Using the same preprocessing, the experiments match images based on tra-ditional EMR and the proposed EMR separately. Based on the proposed EMR the paper achieves more stable registration and higher precision.

Matching Pursuits视频编码中原子匹配块搜索中的权值设计

基于 Matching Pursuits的误差图像编码算法因其基函数的灵活性 ,是一种在低码率视频编码应用中较为理想的算法 ,块能量搜索算法被用于减少该算法的编码复杂度 .针对固定权值加权块搜索算法的不足之处 ,提出了一种自适应加权块搜索算法 ,在不增加算法复杂度的情况下 ,对不同的被编码序列采用不同的权值表完成加权块能量算法 ;在各种情况下均得到了较理想的编码效果 .

Progress in hepatitis B virus-related acute-on-chronic liver failure treatment in China:A large,multicenter,retrospective cohort study using a propensity score matching analysis

Background:Hepatitis B virus-related acute-on-chronic liver failure(HBV-ACLF)has a high short-term mortality.However,the treatment progression for HBV-ACLF in China in the past decade has not been well characterized.The present study aimed to determine whether the HBV-ACLF treatment has significantly improved during the past decade.Methods:This study retrospectively compared short-term(28/56 days)survival rates of two different nationwide cohorts(cohort I:2008-2011 and cohort II:2012-2015).Eligible HBV-ACLF patients were enrolled retrospectively.Patients in the cohorts I and II were assigned either to the standard medical therapy(SMT)group(cohort I-SMT,cohort II-SMT)or artificial liver support system(ALSS)group(cohort IALSS,cohort II-ALSS).Propensity score matching analysis was conducted to eliminate baseline differences,and multivariate logistic regression analysis was used to explore the independent factors for 28-day survival.Results:Short-term(28/56 days)survival rates were significantly higher in the ALSS group than those in the SMT group(P<0.05)and were higher in the cohort II than those in the cohort I(P<0.001).After propensity score matching,short-term(28/56 days)survival rates were higher in the cohort II than those in the cohort I for both SMT(60.7%vs.53.0%,50.0%vs.39.8%,P<0.05)and ALSS(66.1%vs.56.5%,53.0%vs.44.4%,P<0.05)treatments.The 28-day survival rate was higher in patients treated with nucleos(t)ide analogs than in patients without such treatments(P=0.046).Multivariate logistic regression analysis revealed that ALSS(OR=0.962,95%CI:0.951-0.973,P=0.038),nucleos(t)ide analogs(OR=0.927,95%CI:0.871-0.983,P=0.046),old age(OR=1.028,95%CI:1.015-1.041,P<0.001),total bilirubin(OR=1.002,95%CI:1.001-1.003,P=0.004),INR(OR=1.569,95%CI:1.044-2.358,P<0.001),COSSH-ACLF grade(OR=2.683,95%CI:1.792-4.017,P<0.001),and albumin(OR=0.952,95%CI:0.924-0.982,P=0.002)were independent factors for 28-day mortality.Conclusions:The treatment for patients with HBV-ACLF has improved in the past decade.

Egg-spot matching in common cuckoo parasitism of the oriental reed warbler: effects of host nest availability and egg rejection

Background: The success of cuckoo parasitism is thought to depend largely on the extent of egg matching between cuckoo and host eggs, since poor-matching cuckoo egg would lead to more frequent egg rejection by the host. In this study, we investigated how egg-spot matching between the Common Cuckoo(Cuculus canorus) and its host, the Oriental Reed Warbler(Acrocephalus orientalis) is affected by the local parasitism rate, nest availability in breeding synchronization and egg rejection.Methods: We used the paired design of parasitized and their nearest non-parasitized nests where breeding occurred simultaneously to compare egg-spot matching. The image analysis was used to compare four eggshell pattern variables, namely spot size, density, coverage on the different areas of egg surface, and the distribution on the whole egg surface. Egg recognition experiments were conducted to test the effect of egg spots on egg rejection by the host.Results: Our results show that much better matching in almost all spot parameters tested on the side of the egg and the spot distribution on the whole egg occurred in parasitized nests than in non-parasitized nests. Matching of spot density between cuckoo and host eggs in parasitized nests increased with the synchronization between temporal availability of nests and the egg-laying period of female cuckoos. Egg recognition experiments in which the warbler eggs were deliberately painted with extra spots led to a significantly higher egg rejection rate(78.3%) than of unpainted eggs.Conclusion: Our data suggest that both the high temporal encounter rate between cuckoo and warbler nests as well as the high egg rejection ability of the host are important factors for egg-spot matching of the cuckoos.

Resource Allocation Based on User Pairing and Subcarrier Matching for Downlink Non-Orthogonal Multiple Access Networks

The traditional orthogonal multiple access(OMA)is unable to satisfy the needs of large number of smart devices.To increase the transmission rate in the limited spectrum resource,implementation of both non-orthogonal multiple access(NOMA)and successive interference cancelation(SIC)is essential.In this paper,an optimal resource allocation algorithm in NOMA is proposed to maximize the total system rate in a multi-sector multi-subcarrier relay-assisted communication network.Since the original problem is a non-convex problem with mixed integer programming which is non-deterministic polynomial-time(NP)-hard,a three-step solution is proposed to solve the primal problem.Firstly,we determine the optimal power allocation of the outer users by using the approach of monotonic discrimination,and then the optimal user pairing is determined.Secondly,the successive convex approximation(SCA)method is introduced to transform the non-convex problem involving central users into convex one,and the Lagrangian dual method is used to determine the optimal solution.Finally,the standard Hungarian algorithm is utilized to determine the optimal subcarrier matching.The simulation results show that resource allocation algorithm is able to meet the user performance requirements with NOMA,and the total system rate is improved compared to the existing algorithms.

Grouping pilot allocation scheme based on matching algorithm in massive MIMO system

Pilot allocation is one of the effective means to reduce pilot pollution in massive multiple-input multiple-output(MIMO)systems.The goal of this paper is to improve the uplink achievable sum rates of strong users,and ensure the quality of service(QoS)requirements of weak users at the same time,so that the sum rates of system can be improved.Combining with the technical advantage of pilot grouping,a low complexity pilot allocation scheme based on matching algorithm is proposed,which divides the users in the target cell into weak user group and strong user group,and adopts the minimum-maximum matching method to allocate pilots in weak user group.Through the introduction of Hungarian algorithm,a pilot allocation method is designed to ensure the fairness of the strong users.The simulation results show that,compared with the smart pilot allocation scheme,the pilot allocation scheme based on Hungarian algorithm,the pilot allocation scheme based on user grouping and the random pilot allocation scheme,the system performance of the proposed scheme has been effectively improved.

Stochastic Modeling and Assisted History-Matching Using Multiple Techniques of Multi-Phase Flowback from Multi-Fractured Horizontal Tight Oil Wells

In this paper, the methods developed by?[1] are used to analyze flowback data, which involves modeling flow both before and after the breakthrough of formation fluids. Despite the versatility of these techniques, achieving an optimal combination of parameters is often difficult with a single deterministic analysis. Because of the uncertainty in key model parameters, this problem is an ideal candidate for uncertainty quantification and advanced assisted history-matching techniques, including Monte Carlo (MC) simulation and genetic algorithms (GAs) amongst others. MC simulation, for example, can be used for both the purpose of assisted history-matching and uncertainty quantification of key fracture parameters. In this work, several techniques are tested including both single-objective (SO) and multi-objective (MO) algorithms for history-matching and uncertainty quantification, using a light tight oil (LTO) field case. The results of this analysis suggest that many different algorithms can be used to achieve similar optimization results, making these viable methods for developing an optimal set of key uncertain fracture parameters. An indication of uncertainty can also be achieved, which assists in understanding the range of parameters which can be used to successfully match the flowback data.

求解TSP的离散野马优化算法

针对求解TSP问题,提出一种新的元启发式算法离散野马优化算法(DWHO),应用最小位置匹配值法(MPMV)对求解结果进行离散化解码;为提高算法搜索能力,结合野马放牧、交配、领导者交流与选拔行为,引入变邻域搜索策略,增强了算法的局部搜索能力、加快算法收敛速度。选取TSPLIB标准库33个算例进行实验,并与交换序列人工蜂群算法(ABCSS)、离散蜘蛛猴优化算法(DSMO)两种算法进行比较。实验结果表明,DWHO求得的最优解与ABCSS、DSMO两种算法的最优解相比,最优解改进率最大值分别达到4.52%和3.41%。同时,将离散野马优化算法求解TSP收敛速度与以上两种算法进行比较,其收敛速度具有一定的优势。结果表明离散野马优化算法求解能力和精度具有优势。

基于表面增强拉曼光谱的牛肝菌主成分分析及快速鉴定

2021年《中国疾病预防控制中心周报》指出蘑菇中毒是我国最严重的食品安全问题之一,2021年发生蘑菇中毒事件327次,涉及923例患者,其中20例死亡,总死亡率为2.17%,事件中共鉴定出毒蘑菇74种。牛肝菌由于味道鲜美,是人们最喜爱的菌类之一。由于烹调不当或是混入有毒牛肝菌,就会发生牛肝菌中毒事件。如何快速得出牛肝菌的主成分并进行鉴定,成为了一个迫切需要解决的问题。该研究从楚雄市鸿福农贸市场上购买的10个新鲜牛肝菌样品,使用菌盖进行徒手切片,用微波法制备的纳米银溶胶制成银胶装片,置于DXR显微拉曼光谱仪的10倍物镜下,获得10个样品的表面增强拉曼光谱(SERS)。通过对SERS的分析发现10个样品中,样品7、8、10主成分相同,样品6、9主成分相同,其余样品主成分各不相同。以样品1为例,主成分有L-苯基丙氨酸(1583 cm^(-1)环内C—C伸缩振动、1199 cm^(-1)NH 2摇摆振动)、L-组氨酸(1572 cm^(-1)C C伸缩振动、COO-不对称伸缩、1229 cm^(-1)面内环变形振动)、异亮氨酸(1342 cm^(-1)C—H、N—H变形振动、486 cm^(-1)COOH摇摆振动、353 cm^(-1)骨架振动)、L-天冬氨酸(1136 cm^(-1)C—N伸缩振动)、甘氨酸(1386 cm^(-1)COO-变形振动、889 cm^(-1)C—C伸缩振动)、蛋氨酸(681 cm^(-1)C—S反对称伸缩振动)、吡喃糖化幌物(973 cm^(-1)对称环振动)。采用光谱软件OMNIC Specta的建库功能随机挑选10个样品的一条谱线进库,建库后可快速进行光谱匹配度的检索,通过匹配度的高低鉴定待测样品。在10个样品中,除2、10号样品的匹配度小于60%外,其余样品的匹配度都大于60%。样品7、8的匹配度接近且有交叉,说明样品7、8是同一品种,而样品6、9的匹配度接近而交叉项少,说明这两个样品是同一品种或相近品种。DNA检测结果表明样品7、8、10同为白牛肝菌,而样品6、9同为薄瓤假美柄牛肝菌。该实验为牛肝菌的主要成分检测和快速鉴定提供了一种简单可靠的方法。同时,该方法对野生蘑菇的物种鉴定具有很大的应用潜力,在野生菌中毒病例中,迅速确定毒蘑菇种类,从而为抢救病人赢得时间具有重要的意义。为此首次对野生蘑菇子实体进行SERS研究。

产能分享平台企业的盈利模式选择与定价研究

在分享经济背景下,考虑交叉网络外部性效用及平台匹配率,研究产能分享平台的盈利模式选择与定价问题。基于两阶段博弈方法,分析并比较了平台在利润最大化和社会福利最大化条件下选择服务费模式与注册费模式时获得的最大利润。研究发现,在目标时间段内,当平台以利润最大化为目标时,多数情况下选择注册费模式获得的最大利润高于选择服务费模式获得的利润。在特定条件下,也存在平台采取两种盈利模式会获得相同利润的情况。此外,平台最大利润在一定条件下与交叉网络外部性系数和平台对制造能力供应方的匹配率正相关,与对制造能力需求方的匹配率负相关。当平台以社会福利最大化为目标时,选择服务费模式获得的利润高于选择注册费模式时的利润。最后,通过数值算例对上述结果进行了验证。

基于双目视觉技术的茶叶嫩芽定位方法研究

进一步提升茶叶嫩芽定位的准确性及茶叶嫩芽采摘的作业效率,选取双目视觉技术作为切入点,针对其识别、定位、采摘等环节展开设计研究。考虑茶叶嫩芽采摘的基础特征和双目视觉技术的应用条件,合理搭建双目视觉模型,选用立体匹配的核心定位算法,完成茶叶嫩芽的定位方法与采摘功能优化,并布置相应的试验机构,展开定位采摘验证试验。结果表明:基于双目视觉技术的茶叶嫩芽定位方法应用具有显著的优越性,较普通定位方法而言,识别误匹配率可降低至4.01%,平均漏采率为3.20%,嫩芽采摘完整率达93.40%,可以很好地促进茶叶嫩芽的后续处理加工,是采摘茶叶嫩芽的品质化的重要基础保障。

预制UHPC永久模板钢筋混凝土组合梁抗剪性能有限元分析

为了研究预制超高性能混凝土永久模板钢筋混凝土组合梁抗剪性能,选取合适的U型UHPC预制单元本构关系,建立了钢筋混凝土梁的有限元永久模型,并与已有的试验数据进行比较,验证了模型的可靠性,并分析配箍率、剪跨比等参数对超高性能混凝土组合梁抗剪性能的影响。结果显示:超高性能混凝土预制单元可显著提高斜向开裂荷载和极限荷载;预制单元会限制箍筋的作用,所以配箍率对组合梁影响小;剪跨比对组合梁抗剪性能影响大,但是和配箍率一样都会影响其延性。

考虑兴趣序列和特征交互的司机点击率预测模型

车货匹配平台中存在着大量的车货信息,通过对历史数据的分析和处理,能够预测司机点击货物的概率(司机点击率预测),从而为司机推荐货物。据了解,目前还没有研究项目将点击率预测与车货匹配结合起来,更不要说基于此来考虑车货信息中的兴趣序列和特征交互问题。因此,在车货匹配的背景下,文章提出了一种考虑兴趣序列和特征交互的司机点击率预测模型——深度兴趣交互网络(Deep Interest Interaction Network,DIIN)。一方面,在司机兴趣抽取模块中利用Bi-GRU和SENet从司机的历史行为中推断出司机的兴趣点;另一方面,在车货特征交互模块中利用FM和Res Net同时建模低阶和高阶特征交互。通过对某车货匹配平台的数据集进行实验,结果表明模型DIIN与基准模型相比具有更好的性能,即使与DIEN模型相比,在AUC和Log Loss两个评价指标上,模型DIIN分别提升了3.5个百分点和1.8个百分点。这不仅证明了将深度学习和点击率预测用于车货匹配的可行性,也证明了挖掘历史数据中的序列关系和特征交互有助于预测车货匹配中司机点击货物的概率。

鳖龙软肝片联合抗病毒药治疗乙型肝炎肝硬化的回顾性临床研究

目的探讨鳖龙软肝片联合抗病毒药治疗乙型肝炎肝硬化的临床疗效及安全性。方法采用回顾性临床研究,收集湖南中医药大学第一附属医院肝病科2014年1月1日至2016年12月31日诊断为乙型肝炎肝硬化患者的临床资料,共纳入匹配前治疗组216例、匹配前对照组78例。依据基线资料将两组患者进行倾向性评分匹配(propensity score matching,PSM),得到治疗组和对照组各69例。观察PSM后两组患者1年、3年、5年生存率及生存时间,5年内肝硬化临床终点事件发生率和发生所需时间,以评价其疗效;分别观察PSM后两组患者上消化道出血发生率、不同血小板(platelet,PLT)计数层次的两组患者上消化道出血发生率以及其他不良反应,以评价其安全性。结果(1)1年、3年、5年总体生存率比较,治疗组分别为97%、77%、68%,对照组分别为91%、57%、52%,平均生存时间治疗组长于对照组(P<0.05)。(2)肝硬化临床终点事件发生所需平均时间比较,治疗组长于对照组(P<0.05);腹水发生率治疗组低于对照组(P<0.05)。(3)PSM后,两组上消化道出血发生率比较,差异无统计学意义(P>0.05);两组患者按PLT计数不同各分为PLT<30×10^(9)/L、30×10^(9)/L≤PLT<50×10^(9)/L、50×10^(9)/L≤PLT<100×10^(9)/L、PLT≥100×10^(9)/L,各层次上消化道出血发生率差异无统计学意义(P>0.05)。(4)部分患者服用鳖龙软肝片后出现胃脘不适、腹泻、腹胀等不良反应,程度轻微,可自行缓解。结论鳖龙软肝片能提高乙型肝炎肝硬化患者生存率,减少肝硬化腹水事件发生,延缓肝硬化终点事件的发生,有较好的远期疗效,临床安全性较好,不增加上消化道出血的风险。

基于分数阶Fourier变换的chirp-rate调制解调方法研究

本文提出了一种基于分数阶Fourier变换的chirp-rate调制(CRM)非相干解调方法,并导出了其解调器的输出峰值;其次,从多普勒频移和码同步误差两个方面,将本文方法与匹配滤波相干解调方法进行了对比分析,得到了相应的对解调性能影响的解析表达,可以发现chirp-rate调制具有很强的抗多普勒频移能力,但是对码同步误差较为敏感.最后,通过仿真分析,验证了上述理论推导的正确性,并对比了本文方法和匹配滤波相干解调的误码性能.由于本文方法是一种非相干解调,所以相较匹配滤波相干解调差了约3dB.

2008年M_(W)7.9汶川地震早期余震频度衰减速率空间分布特征分析

深入认识余震频度衰减及其影响因素对理解余震触发机理和震后应急救援具有重要意义.然而,由于强震后余震数量庞大,波形相互叠加导致了目录中余震缺失,进而影响了余震频度衰减速率的估计.本研究采用模板匹配技术对2008年M_(W)7.9汶川地震后约50天内连续数据进行扫描,检测余震数量约为模板地震数量的5倍,完备震级由M3.0降低到M2.3.根据余震沿映秀—北川断裂走向优势深度分布的变化,以映秀、汶川、茂县、北川、南坝为界,余震活动大致可分为6个区域.本研究利用最大似然法分别计算了各个区域的余震频度衰减速率,结果显示:以茂县、青川为界,余震频度衰减速率表现出映秀—北川断裂西南段较快、中间段居中、东北段较慢的特征.将余震频度衰减速率和余震空间分布、断裂类型、震后形变、同震形变等进行对比分析,本研究得到以下结论:1、余震频度衰减速率分区与断裂类型分区吻合.其中,映秀—北川断裂西南段余震频度较快衰减速率区域断裂以逆冲为主,中间段为经过各种震源机制类型交替出现的过渡带,映秀—北川断裂东北段余震频度较慢衰减速率区域断裂以右旋走滑为主;2、余震频度衰减速率西南段较快、东北段较慢的空间分布特征与震后形变特征相一致;3、余震频度衰减速率与同震形变相关性不强.结合本研究观测到的同震滑移量较大区域余震分布较少、部分区域余震数目和震后形变空间分布一致性等特征,我们推测汶川地震早期余震可能主要与震后余滑相关,余震频度衰减速率的空间分布差异主要与不同类型断裂震间滑移速率不同相关,震间滑移速率较快的区域余震频度衰减速率较快及震后形变较大.

基于能量传输效率控制的现场混装炸药与岩石匹配方法

炸药与岩石的匹配关系对于提高炸药能量利用率、提升爆破效果与降低成本至关重要。首先分析了钻孔爆破中爆破能量的分配规律,然后考虑现场混装炸药的非理想爆轰特性和岩石应变率效应对岩石钻孔爆破破坏分区计算模型进行了修正,在此基础上建立了基于能量传输效率控制的现场混装炸药-岩石匹配模型,最后结合现场试验对新的炸药-岩石匹配方法的合理性进行验证。结果表明:新方法综合考虑了现场混装炸药非理想爆轰特性和岩石应变率效应对爆破破坏分区范围的影响,可以直观地反映爆破破碎效果及能量有效利用率,更加科学合理。不同炸药-岩石匹配条件下的爆破块度试验证实了匹配结果与传统波阻抗理论并不总是一致,采用新的现场混装炸药-岩石匹配方法,爆破粉矿率较原有炸药参数有明显的降低,爆破大块率从6.7%下降至1%以下,进一步验证了新方法的合理性。

基于改进ORB-FLANN算法的工件图像识别方法

针对传统图像识别算法匹配正确率低、运行时间较长等问题,文中提出了基于改进ORB-FLANN(Oriented FAST and Rotated BRIEF-Fast Library for Approximate Nearest Neighbors)的工件图像识别方法。对ORB算法特征描述、图像特征匹配算法进行修改,解决传统图像识别算法在图像存在尺度和旋转变换情况下存在的弊端并降低误匹配率。该方法对ORB算法检测到的特征点采用SURF(Speeded Up Robust Features)算法添加方向信息并完成特征描述,得到旋转尺度不变性的特征点,结合FLANN算法并引入双向匹配策略进行特征点粗匹配,最后利用渐进采样一致算法进一步剔除误匹配点对完成精匹配。实验结果表明,与其他方法相比,改进算法在处理尺度、旋转等变换图像时,匹配正确率分别提高了2.6%~18.8%和29.5%~43.9%,运行时长均在4 s以内,提高了对工件图像的识别效率和精准性。

考虑供需匹配特性的冷热电联供系统运行策略研究

针对以电定热和以热定电运行策略能量冗余以及混合热电运行策略能源不足的特性,在热电负荷平衡运行策略的基础上,提出了改进的热电负荷平衡运行策略。以北方某酒店为研究对象,并以最大化能源利用率为目标对系统的装机容量进行了优化,同时提出了能源综合指数,研究了在5种运行策略下购买能量和冗余能量对系统性能的影响。然后分析了在不同运行策略下系统的供需匹配特性和改进的热电负荷平衡策略下系统的能量平衡关系。最后,通过算例探究了改进的热电负荷平衡策略对提高系统经济性的作用,并经过对比分析验证了研究的合理性与有效性。研究结果表明,与其他4种运行策略相比,改进的热电负荷平衡运行策略下系统的能源利用率分别提高了4.3%、4.38%、4.75%、4.73%;能源综合指数分别降低了6.58%、5.96%、2.23%、3.45%;系统的年总成本分别降低了11.65%、2.74%、1.64%、0.74%。其中,改进的热电负荷平衡策略下系统的供需匹配性能最优(为0.9382)。

重型柴油机二级增压系统匹配仿真研究

为了降低重型柴油机的燃油消耗率,采用GT-POWER软件建立仿真模型,在一台单级可变截面涡轮增压器(variable geometry turbocharger,VGT)柴油机上开展了二级增压匹配与增压系统参数优化工作。仿真结果表明,所提出的二级增压系统在匹配点能够以最高效率运行,在全工况都能提供足够的进气流量;完全关闭低压级废气旁通阀,正交优化高压级废气旁通阀开度和米勒循环度,能够进一步降低二级增压发动机的燃油消耗率;降低级间中冷温度能够降低泵气损失,提高增压压力,温度由100℃降至50℃在标定点能够使燃油消耗率降低约3 g/(kW·h)。对二级增压及参数优化工作的燃油消耗率改善效果进行了试验验证,低速工况燃油消耗率整体有所下降,高效点燃油消耗率下降4.1%。