基于多目标遗传算法的8×8 S盒的优化设计方法

混沌系统具有非线性、伪随机性、初始值敏感等特性,为基于动力系统构造性能良好的S盒提供了基础,进一步保证了分组加密算法安全性.目前,基于混沌构造S盒的方法大多数针对单个性能指标进行优化,难以获得全面的性能提升.针对此问题,结合混沌映射与多目标遗传算法,提出了一种新的S盒设计方法.首先,利用混沌映射的特性产生初始S盒种群;然后,以S盒的非线性度和差分均匀性为优化目标,基于遗传算法框架对上述两指标进行优化.针对S盒的特点,在优化算法中引入了交换操作,设计了新的变异操作以及非支配序集计算,有效提升了S盒的非线性度和差分均匀性.实验结果表明该算法产生的S盒其差分均匀度为6,非线性度值至少为110,有效提升了S盒的综合性能.

基于数据流的K-S变化检测的动态多目标规划算法

为了更加准确地判断环境是否发生变化并快速追踪动态多目标规划问题(dynamicmulti-objectiveoptimization problem,DMOP)当前时刻的Pareto前沿,提出了一种基于数据流的Kolmogorov-Smirnov(K-S)变化检测的动态多目标规划(DSK-SDMOP)算法。该算法以NSGA-Ⅱ为基础,通过数据流建立2个时刻的检验窗口,再利用K-S检验基于数据流的Pareto最优前沿是否发生变化,检测2个窗口的数据是否服从同一分布来判断环境是否发生变化,并就环境变化的剧烈程度实行相应的应答机制,以提高对环境的适应程度。利用基于数据流的K-S检测方法,对环境变化不会过于敏感,而且不用提前假设对应目标值的分布,易于操作。通过5个动态多目标规划标准测试函数对该算法进行测试,并和现有的2种算法进行对比分析,结果表明该算法处理动态多目标规划问题具有良好的性能。

基于改进YOLOX-S的轻量化煤矸石检测方法研究

目的 为了探索基于现有机器视觉煤矸石检测方法的模型参数量、计算量对检测速度和嵌入式设备的影响,方法 提出一种基于改进的无锚框YOLOX-S轻量化煤矸石检测模型。为使模型能提取更真实的煤矸石特征信息,收集分选现场煤矸石样本,保证实际环境下的煤矸石检测效果,适应实际生产环境。结合CSPNet,将输入的特征图分割成两个分支,实现更丰富的梯度组合,同时减少模型计算量;之后在其中一条分支使用Ghost轻量化卷积,通过少量常规卷积生成一组特征图,达到初次减少计算量和参数量的效果,然后在此特征图基础上经过简单线性变化操作,生成一组新的特征图,将两组特征图进行融合,降低对计算资源需求的同时,也达到了常规卷积相同的特征提取效果;引入LeakyReLU激活函数减弱模型梯度消失的影响,提取更深更多的特征信息;最后融合两个分支特征,保证较高的检测精度,提升模型检测速度。采用CIOU Loss(complete IOU loss)优化目标边界框回归损失函数,使模型回归损失收敛更快,提高模型目标定位能力。结果 与原模型相比,本文改进模型在保证较高的平均精度均值90.51%情况下,模型参数减少47%,计算量减少49%,检测速度达到50帧/s。结论 轻量化煤矸石检测模型使智能化煤矸石检测在实际生产环境中具有一定的应用前景。

基于NSGA-Ⅱ算法的S-CO_(2)再压缩再热燃煤系统多目标优化

以S-CO_(2)再压缩再热循环燃煤发电热力系统为研究对象,以循环热效率ηt和平准化度电成本C LCOE为系统的热力性能和经济性能指标,分析了系统关键参数对系统热力和经济性能的影响规律。基于非支配排序遗传(NSGA-II)算法建立了S-CO_(2)再压缩再热循环燃煤发电热力系统的多目标优化模型,以系统的热力学性能和经济性为目标,得到了系统关键参数的最优解。最后,以再热温度、透平入口温度、主压缩机出口压力、再热压力、主压缩机入口压力、主压缩机入口温度、分流系数为决策变量,对系统进行多目标优化。结果表明:透平入口温度、再热温度的升高会使系统的循环效率和平准化度电成本同时增大,系统的热力性和经济性不能同时达到最优;多目标优化后ηt和C LCOE分别为53.07%、453.43元/(MW·h),相较于设计工况,ηt提高了5.42%,C_(LCOE)降低了5.91%。

基于改进YOLOX-S的苹果成熟度检测方法

准确检测果园中未成熟与成熟的苹果对果园早期作物的负荷管理至关重要,提出一种能够实时检测苹果成熟度,并估算出整棵果树果实数量的方法。为提高YOLOX-S网络在复杂场景下的检测能力,在FPN(特征金字塔)的残差连接处增加了CoordinateAttention(位置注意力);为更好地检测图像中生长密集、存在遮挡、尺寸较小的苹果,将位置损失函数IoU_Loss更换为CIoU_Loss。试验结果表明,所提出的改进YOLOX-S检测算法相较于原算法,mAP值提高约1.97%,苹果低成熟度、中等成熟度和高等成熟度的AP值分别为90.85%、95.10%和80.50%。

基于YOLOv5s的轻量化架空输电线路鸟巢检测网络

架空输电线路上的鸟巢侵占会对铁塔上的电力设备造成安全隐患,间接可能影响整个电力系统的稳定运行。针对目前架空输电线路鸟巢检测模型在复杂场景以及小目标场景下检测精度不高,检测效率低,模型复杂等问题。本研究提出一种基于YOLOv5s框架的轻量化架空输电线路鸟巢检测网络。首先在主干部分采用Fasternet重构YOLOv5s特征提取网络,降低模型复杂度,提高运行速度;然后在特征融合网络部分嵌入ConvMixer层,ConvMixer层的结构设计有助于在特征信息中更好的捕捉空间和通道的关系,提升模型对于小目标的检测能力;最后在特征融合网络部分引入ODConv模块,令送入检测头的特征图包含更多有效特征,提高模型对复杂场景和小目标的检测性能。实验结果表明,本文与基线模型YOLOv5s相比,计算量和模型体积分别减少了86%和72%,平均精度均值达到96.4%,检测速度达到104.2帧/s,验证了本文改进模型的有效性和可行性。

Transcranial Direct Current Stimulation: Effects on Motor and Non-Motor Symptoms of Parkinson’s Disease

Introduction: In the last thirty years, brain neuromodulation techniques have been used as an alternative to pharmacological treatment of neurological disorders. Parkinson’s disease (PD) is a neurodegenerative disorder leading to bradykinesia, rest tremor, postural changes, and non-motor symptoms such as depression, anxiety, sleep disorders, pain, and cognitive decline that compromises executive functions (EFs), responsible for the orderly execution of behaviors and tasks of daily life and intentional and directed actions. To this date, a few studies with transcranial direct current stimulation (tDCS) have shown beneficial effects in PD patients concerning specific motor and non-motor symptoms, targeting the motor cortex and/or prefrontal regions. Objective: The main objective of this study was to evaluate the effects of left prefrontal tDCS across a broad spectrum of motor and non-motor symptoms of PD using established validated scales. Method: Single-blind randomized clinical trial with 18 volunteers with PD, aged between 45 and 80 years (66.1 ± 9.65), who met inclusion and exclusion criteria. Participants were submitted to assessments of motor and non-motor functions employing psychometric scales and tests to evaluate EFs and were randomly divided into two groups: control (sham stimulation) and experimental (active stimulation). All participants were involved in three separate tDCS sessions. The anode was positioned over the left dorsolateral prefrontal cortex and the cathode over the right supraorbital region, with a direct current intensity of 2 mA, lasting 20 minutes. At the end of the three sessions, all participants were reassessed. Results: Significant effects of tDCS on non-motor functions were observed for cognition (verbal fluency of actions, clock copy test, appointment by visual confrontation, and verbal memory with immediate free recall) and subjective assessment of sleep quality (overall restlessness and discomfort in the arms and legs at night, leg and arm cramps at night and distressing dreams). There was also an improvement in the rate of errors and successes for congruent and incongruent stimuli of the Stroop Test. The beneficial effects on motor function were decreased rigidity, improved gait, and greater agility in the finger-tapping test. Conclusion: Three tDCS sessions showed positive results for participants with PD, producing significant improvements in various motor and non-motor functions, including sleep quality, cognition, and EFs. Additionally, the present results indicate that tDCS neuromodulation of the left dorsolateral prefrontal cortex region is feasible, safe, and provides significant objective benefits for PD patients.

基于Map Objects的广东省林火监测地理信息系统开发

阐述了在VisualBasic环境下利用MapObjects控件进行广东省林火监测地理信息系统的开发。分析了该系统的主要特点,即借助卫星遥感技术提供的经纬度信息,可以将火点信息直观显示在电子地图上,为防火部门提供详细的地理信息和资源分布信息,对快速准确的火灾扑救工作起到了辅助决策作用。

基于改进DeepSORT和FastReID的室内多目标人员跨镜识别与跟踪

为解决利用视频分析实现目标检测、目标跟踪和行人重识别存在的诸如目标框重框、遮挡等问题,提出了一种基于改进DeepSORT和FastReID的室内多目标人员跨镜追踪的方法。该方法使用YOLOv5s进行人员检测、DeepSORT进行人员跟踪、FastReID进行人员重识别。采用EIOU-NMS算法解决了YOLOv5s人员检测过程中出现的重框问题;在FastReID的特征提取网络中引入了NEUFA注意力机制,并使用优化后的FastReID的特征提取网络替换了DeepSORT原有特征提取网络,降低了DeepSORT跟踪过程中由于遮挡导致的ID跳变的次数;结合注意力机制、人员动态图像库与运动估计的方法减少了人员识别过程中因遮挡导致的人员无法识别和错误识别的次数。结果表明:EIOU-NMS算法将人员检测准确率提升了0.8%,召回率提升了0.4%;替换了特征网络后的DeepSORT将人员跟踪中的ID跳变次数降低了38.46%;结合注意力机制、人员动态图像库和运动估计方法之后,None的次数减少了79.8%,误识别次数减少了91.2%。研究结果能够提升人员识别与跟踪的准确性,降低遮挡对人员跟踪和识别带来的影响。

苜蓿体内H_(2)S信号与Ca^(2+)调节气孔运动的作用机制

为探究H_(2)S信号在苜蓿(Medicago sativa)体内调节气孔运动的作用,及在此过程中H_(2)S与Ca^(2+)的关系,以蒺藜苜蓿(Medicago truncatula)的野生型和钙离子转运体突变体为试验材料,分别从转录水平、细胞水平和生理水平开展研究。采用qRT-PCR比较相关基因的表达量变化、荧光探针显示体内Ca^(2+)含量、电极法测定H_(2)S含量、光学显微镜观察和测量气孔孔径等。结果表明:蒺藜苜蓿突变体NF3011和NF2734体内H_(2)S的含量与野生型相比极显著降低(P<0.01);H_(2)S信号在一定程度上抑制钙离子转运体编码基因MTR_6g027580的表达;外源生理浓度H_(2)S熏蒸可诱导蒺藜苜蓿气孔关闭,与Ca^(2+)通道阻断剂LaCl_(3)联合处理对野生型气孔运动未产生影响,而在突变体中的结果截然相反;利用荧光探针测定保卫细胞内的Ca^(2+)含量,所得结果与气孔孔径的变化规律完全一致。综上所述,H_(2)S信号促进叶片保卫细胞内Ca^(2+)的含量增加,最终表现为植物气孔孔径变小,在此过程中胞内Ca^(2+)含量变化主要通过Ca^(2+)转运体进行,少部分依赖Ca^(2+)离子通道。该研究结果不仅在理论上丰富了H_(2)S信号的作用机制,更具应用于苜蓿生产实践并推广于其他作物的潜力。

基于SuperMap Objects荆州市旅游地理信息系统的设计与实现

对荆州市旅游地理信息系统的设计与实现进行描述和分析,利用SuperMap Objects组件、VB6.0和SQL Server2000,实现了荆州市旅游地理信息系统,这对于发展荆州市旅游经济具有重要的意义。

Recent crustal movement and great earthquakes in Qinghai-Tibet sub-plate

Crustal movement and incremental-movement data observed repeatedly at GPS stations during 1999 -2009 were analyzed to study the effect of two earthquakes of Ms8.1 and Ms8.0 that occurred in 2001 and 2008, respectively, in Qinghai-Tibet sub-plate and its eastern margin. The result revealed certain anoma- lous pre-earthquake deformation and some large co-seismic changes. Prior to the 2008 Wcnchuan Ms8.0 earthquake, the seismogenic Kunlunshan fault zone became a geographic boundary between different regional movements. At the time of the earthquake, there was an average cross-fault crustal shortening of - 1.04 m and an average right-lateral strike slip of 0.76 m along the ruptured segment, as well as a strain-energy release of -62.66 ×10.7.

The Modulation and Control of the Gecko's Foot Movement

The modulation and control of gecko＇s foot movements were studied electrophysiologically in order to design the motor control system of a gecko-mimic robot. In this study （1） the anatomy of the peripheral nerves controlling the gecko＇s foot movements was determined; （2） the relationship between the limb nerves of the gecko and its foot motor patterns was studied; （3） the afferent impulses of the nerves evoked by rubbing the gecko＇s toes and palm were recorded; （4） copying the natural patterns of movement of the gecko＇s foot （abduction, adduction, flexion, and revolution） and its limb nerve modulation and control mechanism, the nerves were stimulated under computer control, and the results recorded by CCD. Results suggest that gecko＇s foot movements can be successfully controlled by artificial electrical signals.

Molecular imaging of movement disorders

Positron emission tomography measures the activity of radioactively labeled compounds which distribute and accumulate in central nervous system regions in proportion to their metabolic rate or blood flow. Specific circuits such as the dopaminergic nigrostriatal projection can be studied with ligands that bind to the pre-synaptic dopamine transporter or post-synaptic dopamine receptors (D1 and D2). Single photon emission computerized tomography (SPECT) measures the activity of similar tracers labeled with heavy radioactive species such as technetium and iodine. In essential tremor, there is cerebellar hypermetabolism and abnormal GABAergic function in premotor cortices, dentate nuclei and ventral thalami, without significant abnormalities in dopaminergic transmission. In Huntington&#x02019;s disease, there is hypometabolism in the striatum, frontal and temporal cortices. Disease progression is accompanied by reduction in striatal D1 and D2 binding that correlates with trinucleotide repeat length, disease duration and severity. In dystonia, there is hypermetabolism in the basal ganglia, supplementary motor areas and cerebellum at rest. Thalamic and cerebellar hypermetabolism is seen during dystonic movements, which can be modulated by globus pallidus deep brain stimulation (DBS). Additionally, GABA-A receptor activity is reduced in motor, premotor and somatosensory cortices. In Tourette&#x02019;s syndrome, there is hypermetabolism in premotor and sensorimotor cortices, as well as hypometabolism in the striatum, thalamus and limbic regions at rest. During tics, multiple areas related to cognitive, sensory and motor functions become hypermetabolic. Also, there is abnormal serotoninergic transmission in prefrontal cortices and bilateral thalami, as well as hyperactivity in the striatal dopaminergic system which can be modulated with thalamic DBS. In Parkinson&#x02019;s disease (PD), there is asymmetric progressive decline in striatal dopaminergic tracer accumulation, which follows a caudal-to-rostral direction. Uptake declines prior to symptom presentation and progresses from contralateral to the most symptomatic side to bilateral, correlating with symptom severity. In progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), striatal activity is symmetrically and diffusely decreased. The caudal-to-rostral pattern is lost in PSP, but could be present in MSA. In corticobasal degeneration (CBD), there is asymmetric, diffuse reduction of striatal activity, contralateral to the most symptomatic side. Additionally, there is hypometabolism in contralateral parieto-occipital and frontal cortices in PD; bilateral putamen and cerebellum in MSA; caudate, thalamus, midbrain, mesial frontal and prefrontal cortices in PSP; and contralateral cortices in CBD. Finally, cardiac sympathetic SPECT signal is decreased in PD. The capacity of molecular imaging to provide in vivo time courses of gene expression, protein synthesis, receptor and transporter binding, could facilitate the development and evaluation of novel medical, surgical and genetic therapies in movement disorders.

Small objects detection in UAV aerial images based on improved Faster R-CNN

In order to solve the problem of small objects detection in unmanned aerial vehicle(UAV)aerial images with complex background,a general detection method for multi-scale small objects based on Faster region-based convolutional neural network(Faster R-CNN)is proposed.The bird’s nest on the high-voltage tower is taken as the research object.Firstly,we use the improved convolutional neural network ResNet101 to extract object features,and then use multi-scale sliding windows to obtain the object region proposals on the convolution feature maps with different resolutions.Finally,a deconvolution operation is added to further enhance the selected feature map with higher resolution,and then it taken as a feature mapping layer of the region proposals passing to the object detection sub-network.The detection results of the bird’s nest in UAV aerial images show that the proposed method can precisely detect small objects in aerial images.

基于遥感影像的震后避难空间快速提取模型研究——以2021年云南漾濞M_(S)6.4地震为例

震后避难空间是居民遭遇地震时紧急疏散、避难、临时生活的重要区域。以无人机影像为基础,采用影像面向对象分类与GIS栅格化的分析方法,构建震后避难空间评价指标,建立基于遥感影像的震后避难空间快速提取模型,并以2021年云南漾濞M_(S)6.4地震为例,将避难空间提取的结果与震后居民实际选取的避难空间进行比较。结果表明:模型共计提取可用避难空间70个,根据目标函数F得到最优避难空间5个,其中每个避难空间在漾濞M_(S)6.4地震中实际帐篷数量分别为72、55、54、30、44顶,模型计算结果与实际结果匹配。

Assessing gray matter volume in patients with idiopathic rapid eye movement sleep behavior disorder

Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients(male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls(male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume(GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Ethics Committee of Huashan Hospital(approval No. KY2013-336) on January 6, 2014. This trial was registered in the ISRCTN registry(ISRCTN18238599).

Development Progress of China’s First Mars Exploration Mission:Its Scientific Objectives and Payloads

China’s first Mars exploration mission is scheduled to be launched in 2020.It aims not only to conduct global and comprehensive exploration of Mars by use of an orbiter but also to carry out in situ observation of key sites on Mars with a rover.This mission focuses on the following studies:topography,geomorphology,geological structure,soil characteristics,water-ice distribution,material composition,atmosphere and ionosphere,surface climate,environmental characteristics,Mars internal structure,and Martian magnetic field.It is comprised of an orbiter,a lander,and a rover equipped with 13 scientific payloads.This article will give an introduction to the mission including mission plan,scientific objectives,scientific payloads,and its recent development progress.

How non-rapid eye movement sleep and Alzheimer pathology are linked

Alzheimer's disease(AD)is a multifactorial neurodegenerative disorder characterized by the presence of senile plaques and neurofibrillary tangles.Research attempts to identify characteristic factors that are associated with the presence of the AD pathology on the one hand and that increase the risk of developing AD on the other.Changes in non-rapid eye movement(NREM)sleep may meet both requirements for various reasons.First,NREM-sleep is important for optimal memory function.In addition,studies report that the presence of AD pathology is associated with NREM-sleep changes.Finally,more and more results appear to suggest that sleep problems are not only a symptom of AD but can also increase the risk of AD.Several of these studies suggest that it is primarily a lack of NREM-sleep that is responsible for this increased risk.However,the majority investigated sleep only through subjective reporting,as a result of which NREMsleep could not be analyzed separately.The aim of this literature study is therefore to present the results of the studies that relate the AD pathology and NREM-sleep(registered by electroencephalography).Furthermore,we try to evaluate whether NREM-sleep analysis could be used to support the diagnosis of AD and whether NREM-sleep deficiency could be a causal factor in the development of AD.

渤海湾盆地中部428构造带近S-N向走滑断裂的形成时期及其在中生代期间的调节转换作用

渤海湾盆地中部428构造带自印支期以来经历了多期次构造运动叠加改造过程,区域内发育了大量的近S-N向与近EW向褶皱、断层构造,并控制了潜山的形成。然而目前对428构造带的研究仅局限于探索区域内潜山构造成因及其油气圈闭特性,对区域内的断裂系统,尤其是发育的大量近S-N向断裂的形成时期及其后期演化过程中所起到的调控作用尚不明确。鉴于此,为明确其形成时期、探索其对区域构造格局演化模式所产生的影响,基于前人的研究成果,以石臼坨凸起东侧428构造带为主要研究对象,通过对该区域典型的地震剖面进行精确解析,对其展开了系统性的研究。研究结果表明:(1) 428构造带与石臼坨凸起东侧连接处存在一条近S-N向走滑断裂;(2)该走滑断裂的形成最早可追溯至印支期。根据古生界褶皱和薄底构造的分布特征可知,该走滑断裂最初为近E-W向逆冲推覆断裂的侧向断坡;(3)近S-N向走滑断裂阻挡了燕山期NWW向的逆冲推覆作用,从而控制古生界和中生界大量协调褶皱的发育。而近E-W向断裂表现为压扭性质,控制了中生界雁列式褶皱的形成。基于以上认识,认为该近S-N向走滑断裂在印支-燕山期均起到了重要的调控作用,是一个重要的调节转换带。