Kinematic calibration under the expectation maximization framework for exoskeletal inertial motion capture system

This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters are calibrated by the traditional calibration method at first. Then, in order to calibrate the parameters affected by the random colored noise, the expectation maximization (EM) algorithm is introduced. Through the use of geometric parameters calibrated by the traditional calibration method, the iterations under the EM framework are decreased and the efficiency of the proposed method on embedded system is improved. The performance of the proposed kinematic calibration method is compared to the traditional calibration method. Furthermore, the feasibility of the proposed method is verified on the EI-MoCap system. The simulation and experiment demonstrate that the motion capture precision is significantly improved by 16.79%and 7.16%respectively in comparison to the traditional calibration method.

Parental Educational Expectations,Academic Pressure,and Adolescent Mental Health:An Empirical Study Based on CEPS Survey Data

Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based on the baseline data of the China Education Panel Survey,which was collected within one school year during 2013–2014.It included 19,958 samples from seventh and ninth graders,who ranged from 11 to 18 years old.After removing missing values and conducting relevant data processing,the effective sample size for analysis was 16344.The OLS(Ordinary Least Squares)multiple linear regression analysis was used to examine the relationship between parental educational expectations,academic pressure,and adolescents’mental health problems.In addition,we established an interaction term between parents’educational expectations and academic pressure to investigate the moderating effect of academic stress.Results:The study found that adolescents whose parents had high educational expectations reported less mental health problems.(β=−0.195;p<0.001).Additionally,adolescents who had high academic pressure reported more mental health problems.(β=0.649;p<0.001).Furthermore,the study found that academic pressure had a significant moderating effect on the relationship between parental educational expectations and adolescents’mental health problems(β=0.082;p<0.001).Conclusion:Parental educational expectations had a close relationship with adolescents’mental health problems,and academic pressure moderated this relationship.For those adolescents with high levels of academic pressure,the association between high parental educational expectations and mental health problems became stronger.On the contrary,for those adolescents with low levels of academic pressure,the association between high parental educational expectations and mental health problems became weaker.These findings shed new light on how parental educational expectations affected adolescent mental health problems and had significant implications for their healthy development.

Exact controllability of rational expectations model with multiplicative noise and input delay

This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a sufficient condition for the exact controllability of the rational expectations model.In particular,we derive a sufficient Gramian matrix condition and a rank condition for the delay-free case.The key is the solvability of the backward stochastic difference equations with input delay which is derived from the forward and backward stochastic system.

Exceeding Expectations

The Chinese economy continued to rebound and made solid progress in 2023,despite the complex international situation and numerous risks and challenges.The accelerated economic structural transformation and upgrade,coupled with increasing economic resilience,has resulted in various highlights.

The study of a neutron spectrum unfolding method based on particle swarm optimization combined with maximum likelihood expectation maximization

The neutron spectrum unfolding by Bonner sphere spectrometer(BSS) is considered a complex multidimensional model,which requires complex mathematical methods to solve the first kind of Fredholm integral equation. In order to solve the problem of the maximum likelihood expectation maximization(MLEM) algorithm which is easy to suffer the pitfalls of local optima and the particle swarm optimization(PSO) algorithm which is easy to get unreasonable flight direction and step length of particles, which leads to the invalid iteration and affect efficiency and accuracy, an improved PSO-MLEM algorithm, combined of PSO and MLEM algorithm, is proposed for neutron spectrum unfolding. The dynamic acceleration factor is used to balance the ability of global and local search, and improves the convergence speed and accuracy of the algorithm. Firstly, the Monte Carlo method was used to simulated the BSS to obtain the response function and count rates of BSS. In the simulation of count rate, four reference spectra from the IAEA Technical Report Series No. 403 were used as input parameters of the Monte Carlo method. The PSO-MLEM algorithm was used to unfold the neutron spectrum of the simulated data and was verified by the difference of the unfolded spectrum to the reference spectrum. Finally, the 252Cf neutron source was measured by BSS, and the PSO-MLEM algorithm was used to unfold the experimental neutron spectrum.Compared with maximum entropy deconvolution(MAXED), PSO and MLEM algorithm, the PSO-MLEM algorithm has fewer parameters and automatically adjusts the dynamic acceleration factor to solve the problem of local optima. The convergence speed of the PSO-MLEM algorithm is 1.4 times and 3.1 times that of the MLEM and PSO algorithms. Compared with PSO, MLEM and MAXED, the correlation coefficients of PSO-MLEM algorithm are increased by 33.1%, 33.5% and 1.9%, and the relative mean errors are decreased by 98.2%, 97.8% and 67.4%.

Iterative Receiver for Orthogonal Time Frequency Space with Index Modulation via Structured Prior-Based Hybrid Belief and Expectation Propagation

Orthogonal Time Frequency Space(OTFS)signaling with index modulation(IM)is a promising transmission scheme characterized by high transmission efficiency for high mobility scenarios.In this paper,we study the receiver for coded OTFS-IM system.First,we construct the corresponding factor graph,on which the structured prior incorporating activation pattern constraint and channel coding is devised.Then we develop a iterative receiver via structured prior-based hybrid belief propagation(BP)and expectation propagation(EP)algorithm,named as StrBP-EP,for the coded OTFS-IM system.To reduce the computational complexity of discrete distribution introduced by structured prior,Gaussian approximation conducted by EP is adopted.To further reduce the complexity,we derive two variations of the proposed algorithm by using some approximations.Simulation results validate the superior performance of the proposed algorithm.

Self-Frustration of Expectations in Major Depressive Disorder: The Syncytiopathy Hypothesis of Depression Revisited

This paper is a further elaboration of my model of the pathophysiology of major depressive disorder focusing on imbalances of glial-neuronal interactions in tripartite synapses and the glial network (syncytium). Basically, it is proposed that the connexin proteins building gap junctions in the glial syncytium are underexpressed or dysfunctional in major depression, called syncytiopathy. As a compensatory effect the astrocytic receptors in tripartite synapses are overexpressed. This leads to protracted synaptic information processing because of a relative lack of neurotransmitter substances for the occupancy of astrocytic receptors. Based on a new biophysical formal description of astrocytic receptors as expectation variables it can be shown that the protracted processing of sensory information frustrate the full comprehension of the expected event, since it cannot be grasped in time. Moreover, expectation frustration may stress the glial syncytium aggravating memory impairment. This cyclic process of dysbalanced synaptic information processing is characterized as self-frustration of expectations explanatory for the main cognitive dysfunctions in major depression as slowing down processing speed, deficits in attention and working memory. The main result of the study is that patients with major depression cannot fully acknowledge the existence of an intended event.

Complete moment convergence for ND random variables under the sub-linear expectations

In this article,we establish a general result on complete moment convergence for arrays of rowwise negatively dependent(ND)random variables under the sub-linear expectations.As applications,we can obtain a series of results on complete moment convergence for ND random variables under the sub-linear expectations.

The Effects of Job Insecurity, Emotional Exhaustion, and Met Expectations on Hotel Employees’ Pro-Environmental Behaviors: Test of a Serial Mediation Model

There are a plethora of empirical pieces about employees’pro-environmental behaviors.However,the extant literature has either ignored or not fully examined various factors(e.g.,negative or positive non-green workplace factors)that might affect employees’pro-environmental behaviors.Realizing these voids,the present paper proposes and tests a serial mediation model that examines the interrelationships of job insecurity,emotional exhaustion,met expectations,and proactive pro-environmental behavior.We used data gathered from hotel customer-contact employees with a time lag of one week and their direct supervisors in China.After presenting support for the psychometric properties of the measures via confirmatory analysis in LISREL 8.30,the abovementioned linkages were gauged using the PROCESS plug-in for statistical package for social sciences.The findings delineated support for the hypothesized associations.Specifically,emotional exhaustion and met expectations partly mediated the effect of job insecurity on proactive pro-environmental behavior.More importantly,emotional exhaustion and met expectations serially mediated the influence of job insecurity on proactive pro-environmental behavior.These findings have important theoretical implications as well as significant implications for diminishing job insecurity,managing emotional exhaustion,increasing met expectations,and enhancing ecofriendly behaviors.

Exceeding Expectations

Despite of the negative impact of the COVID-19 pandemic,China’s economic growth remained stable in 2022,which will benefit China-Africa economic cooperation this year.China’s GDP growth reached 3 percent year on year in 2022,the National Bureau of Statistics said on 16 January.

The Current Situation and Future Expectationsof China's Pilot Boatsl

Pilots need to board the ship for pilotage,but there are risks or potential dangers in the transfer of pilot.The author reviewed the history of the development of pilot boats,analyzed the potential risks or dangers of transferring pilot,proposed that pilot boat shall have the function of ensuring the safety of pilot when embarking or disembarking the ships,some suggestions on the future design and manufacture of Chinese pilot boats are also given according to the advantages and disadvantages of domestic and foreign pilot boats.

政策感知、组织创新氛围与人才创新绩效——人才自我创新期待的中介作用

在创新驱动发展背景下,区域创新与组织创新的最终落脚点是人才创新。以人才自我创新期待为中介变量,结合东部城市调查数据构建结构方程模型,系统考察政策感知与组织创新氛围对人才创新绩效的作用机制。研究结果表明,政策感知和组织创新氛围均对人才创新绩效具有显著正向影响;人才自我创新期待在政策感知与人才创新绩效之间、组织创新氛围与人才创新绩效之间均发挥中介作用;与政策感知相比,组织创新氛围对人才创新绩效的影响更显著。上述研究结论为解释政策感知和组织创新氛围影响人才创新绩效的内在机理提供了新思路,有助于政策制定者和组织管理者通过激发人才自我创新期待提高创新绩效。

医患共同决策对患者家属诊疗期望值及满意度的影响

应用病例对照研究方法对拟行冠状动脉旁路移植术的患者进行医患共同决策干预。研究发现,经过医患共同决策干预的患者和家属,沟通后对诊疗结果的期望值明显减低,且沟通诊疗期望值低于传统方式沟通的患者和家属;在满意度测评中,干预组满意度和患者参与满意度调查的比例高于对照组,且干预组患者主导的满意度得分高于对照组和干预组家属主导的满意度得分。积极应用医患共同决策能够合理调控患者及其家属对诊疗行为的期望值,提升患者满意度,值得在国内医疗机构推广。

基于期望核密度离群因子的离群点检测算法

针对基于密度的离群点检测方法在不同分布的数据集上检测精度低的问题,提出了一种基于期望核密度离群因子的离群点检测算法。首先,引入k近邻和反向k近邻扩展邻域空间(ENS)代替传统的k邻域范围,更加全面地考虑数据对象的邻域信息;其次,在传统核密度估计(KDE)方法的基础上引入多元高斯函数,在扩展邻域空间内估计数据对象的密度,同时借鉴自适应核带宽的思想,更好地适应不同数据集的数据分布;然后,给出期望距离的概念,进一步区分局部离群点和位于低密度区域的正常点;最后,定义了期望核密度离群因子刻画数据对象离群程度。在人工数据集和真实数据集上对所提算法进行实验验证,并与部分传统算法进行对比,验证了所提算法的有效性。

老年膝骨性关节炎患者治疗期望及其影响因素分析

目的探讨老年膝骨性关节炎(knee osteoarthritis,KOA)患者治疗期望及其影响因素。方法将2021年10月至2022年12月180例老年KOA患者作为研究对象,采用可信度/期望问卷(CEQ)中期望量表评估治疗期望,并评估不同人口特征间治疗期望差异;采用多元线性回归分析老年KOA患者治疗期望的影响因素。结果所有老年KOA患者治疗期望得分(16.64±3.00)分,其中年龄>75岁、KOA严重程度Kellgren-Lawrence(KL)为Ⅲ~Ⅳ级、焦虑评分<8分、疼痛灾难化评分<38分者治疗期望得分较年龄60~75岁、KOA严重程度为Ⅰ~Ⅱ级、焦虑评分≥8分及疼痛灾难化评分≥38分者高(P<0.05)。以治疗期望为因变量,年龄、焦虑、KOA严重程度、疼痛灾难化为自变量进行多元线性逐步回归,结果显示,年龄、KOA严重程度与老年KOA患者治疗期望呈正相关(β=0.048、0.992),焦虑、疼痛灾难化与老年KOA患者治疗期望呈负相关(β=-0.272、-0.068)(P<0.05)。结论老年KOA患者治疗期望与年龄、焦虑程度、KOA严重程度及疼痛灾难化有关。

生鲜电商平台消费者购菜意愿多元提升路径及适配组态研究

基于南昌市519份调查数据,运用技术接受模型3和期望确认理论模型,采用fsQCA方法对生鲜电商平台消费者购菜意愿进行组态分析,探讨消费者购菜意愿适配组态的要素构成条件及提升策略。结果表明:单一条件变量均不是生鲜电商平台消费者购菜意愿的必要条件,说明变量间可能存在替代作用;存在乐趣性与顾客认可型路径、适应性与情感导向型路径、体验感与顾客评价型路径、个性化与挑战导向型路径、影响力与便利导向型路径等5条产生高购菜意愿的路径;其中,高主观规范和高满意度作为核心条件存在于4条路径中,对生鲜电商平台消费者产生购菜意愿发挥着更普适的作用。基于此,建议整合多元路径,根据组态效应调整购菜意愿提升策略;确保产品质量,提升售后服务,重视满意度的普适性作用;建立良好口碑,发挥社交圈的积极作用,以实现平台发展的良性循环。

基于期待视野的小学语文“整本书阅读”教学模式构建

《义务教育语文课程标准(2022年版)》明确将“整本书阅读”设置为首位学习任务群,“整本书阅读”的地位明显提升,重要性更加凸显。“整本书阅读”的成效关乎小学语文教学质量与水平,要确保“整本书阅读”的成效,就需要具有主体性、差异性、能动性等特征的“期待视野”理论的融入与融通。基于“期待视野”理论,构建课前、课中、课后三维一体的“整本书阅读”教学模式,才能体现学生学习主体的重要性,有效提升“整本书阅读”教学质量,实现不断巩固提升学生阅读水平与语文素养的目标。

驾驶疲劳对危险化学品道路运输事故风险的影响规律

近年来,随着危险化学品使用量的急剧攀升,危险化学品道路运输事故率也呈现上升的趋势,且此类事故的发生往往会导致严重后果。为研究危险化学品道路运输事故动态风险变化规律,在修正贝叶斯网络模型基础上,利用2017—2021年历史数据进行机器学习,根据驾驶疲劳程度计算得到“驾驶人行为”动态节点的状态转移概率矩阵,建立基于动态贝叶斯网络(Dynamic Bayesian Network,DBN)的危险化学品道路运输动态风险预测模型并进行推理分析。研究显示:在驾驶3 h内,驾驶人“疲劳驾驶”发生概率随时间推移而增加,但增幅有所下降;在最常见情境下,随驾驶人“疲劳驾驶”概率增加,“侧翻”和“碰撞”事故类型的发生概率明显增加,进而导致“泄漏”事故后果的发生概率有所增加;驾驶人“疲劳驾驶”概率增加会导致“有伤亡事故”发生概率增加,即加重事故的严重程度;在驾驶3 h内,“侧翻”“碰撞”“泄漏”和“有伤亡事故”发生概率的变化趋势与驾驶人“疲劳驾驶”发生概率的变化趋势一致。

备孕女性HPV筛查及其疫苗接种状况调查

目的:调查备孕女性人乳头瘤病毒(HPV)感染情况并分析HPV疫苗接种影响因素。方法:收集2022年1月-2023年1月本院健康检查的211例备孕女性宫颈样本,采用聚合酶链式反应-反向点杂交法进行HPV感染亚型分型,通过问卷调查备孕女性HPV疫苗接种情况,分析影响备孕女性HPV疫苗接种影响因素。结果:备孕女性HPV感染率为22.7%,其中高危型HPV感染率为81.25%,主要HPV感染亚型为HPV52(18.8%)、HPV16(10.4%)。HPV单一型感染率为20.6%,多重感染率为14.6%。211例HPV疫苗接种率为14.7%,文化水平低、不知道HPV疫苗是影响备孕女性HPV疫苗接种的影响因素(P<0.05)。结论:本次调查的备孕女性HPV感染率为22.7%,以HPV52、HPV16为主要感染亚型;HPV疫苗接种率较低,应加强对备孕女性相关知识宣传,提高HPV疫苗接种率。