Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework

This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular spacing.In addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any overshoots.The significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient profiles.Furthermore,all variables existing in the entire system are analyzed to be convergent.Simulation and experimental results are provided to validate the utility of suggested solution.

A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles

The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled vehicle.In this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol approach.Furthermore,the interdependence among the pre-scribed parameters is discussed.To validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach.

Environmental Impact Assessment Follow-Up of Seismic Survey Offshore Activities in Brazil

Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest from scientists and practitioners, though it is recognized as one of the weakest points of EIA systems globally. Also, EIA follow-up is influenced by the context, mainly in terms of the types of projects or activities and their related impacts on the environment. Therefore, the present paper is focused on the investigation of the follow-up stage applied to the activity of seismic survey coupled with offshore oil & gas exploitation in Brazil. Research was based on a qualitative approach that included document analysis and semi-structured interviews with analysts involved in EIA processes, and sought to generate evidence of effectiveness of the EIA follow-up as conducted by the Federal Environment Agency (Ibama) in order to situate the practice of follow-up in the broader context of international best practice principles. Based on the findings, it was concluded that, due to the peculiarities of offshore seismic survey, it is necessary to promote adaptations in the procedures for monitoring impacts in order to ensure proper alignment with the principles and conceptual foundations that guide EIA practice. Specifically, the timing of the execution of the activity imposes challenges for its integration into the “conventional” cycle that has guided the monitoring of the impacts in the EIA of projects.

Parent-Reported Reasons for Loss-to-Follow Up in Patients Hospitalized at the Neonatology Unit at Laquintinie

Introduction: Despite the known benefits of newborn follow-up clinics, attendance has historically been difficult. Infants with reported follow-up difficulty have a greater incidence of severe sensorimotor and cognitive deficits and poorer access to early intervention programs. Our objective was to determine the parent-reported reasons for loss-to-follow up in patients hospitalised at the neonatology unit of Laquintinie Hospital. Methodology: We carried out a cross-sectional study through phone interviews with parents/caregivers of patients hospitalised at Laquintinie over a 2-year period from 1st January 2021 to 31st December 2022. A non-standardised structured interview guide was used for data collection. Loss-to-follow up referred to absence to at least one visit as recorded in the neonatal follow-up chart. All necessary administrative and ethical considerations were duly respected. Results: Most neonates were born through vaginal delivery (n = 313, 69.45%). The neonates were admitted at a median gestational age of 33 weeks (Q1-Q3;32 - 35) and the median duration of hospitalisation was 12 days (Q1 - Q3;8 - 18). A total of 23 neonates had died at the time of interview giving a mortality rate of 5.1%. The three most reported reasons for loss-to-follow-up was lack of money (n = 310, 68.13%), assumption that follow-up had ended (n = 37, 8.13%), and newborn that died (n = 23, 5.1%). Conclusion: This study highlights the significant impact of financial constraints and absence of a robust follow-up system on poor uptake of neonatal follow-up post-discharge in resource limited settings like Cameroon. Our results serve as advocacy for national health insurance especially in neonates.

Finite-Time Sideslip Differentiator-Based LOS Guidance for Robust Path Following of Snake Robots

This paper presents a finite-time sideslip differentiator-based line-of-sight(LOS)guidance method for robust path following of snake robots.Firstly,finite-time stable sideslip differentiator and adaptive LOS guidance method are proposed to counteract sideslip drift caused by cross-track velocity.The proposed differentiator can accurately observe the cross-track error and sideslip angle for snake robots to avoid errors caused by calculating sideslip angle approximately.In our method,the designed piecewise auxiliary function guarantees the finite-time stability of position errors.Secondly,for the case of external disturbances and state constraints,a Barrier Lyapunov functionbased backstepping adaptive path following controller is presented to improve the robot’s robustness.The uniform ultimate boundedness of the closed-loop system is proved by analyzing stability.Additionally,a gait frequency adjustment-based virtual velocity control input is derived to achieve the exponential convergence of the tangential velocity.At last,the availability and superiority of this work are shown through simulation and experiment results.

Constrained Moving Path Following Control for UAV With Robust Control Barrier Function

This paper studies the moving path following(MPF)problem for fixed-wing unmanned aerial vehicle(UAV)under output constraints and wind disturbances.The vehicle is required to converge to a reference path moving with respect to the inertial frame,while the path following error is not expected to violate the predefined boundaries.Differently from existing moving path following guidance laws,the proposed method removes complex geometric transformation by formulating the moving path following problem into a second-order time-varying control problem.A nominal moving path following guidance law is designed with disturbances and their derivatives estimated by high-order disturbance observers.To guarantee that the path following error will not exceed the prescribed bounds,a robust control barrier function is developed and incorporated into controller design with quadratic program based framework.The proposed method does not require the initial position of the UAV to be within predefined boundaries.And the safety margin concept makes error-constraint be respected even if in a noisy environment.The proposed guidance law is validated through numerical simulations of shipboard landing and hardware-in-theloop(HIL)experiments.

LSTM-DPPO based deep reinforcement learning controller for path following optimization of unmanned surface vehicle

To solve the path following control problem for unmanned surface vehicles(USVs),a control method based on deep reinforcement learning(DRL)with long short-term memory(LSTM)networks is proposed.A distributed proximal policy opti-mization(DPPO)algorithm,which is a modified actor-critic-based type of reinforcement learning algorithm,is adapted to improve the controller performance in repeated trials.The LSTM network structure is introduced to solve the strong temporal cor-relation USV control problem.In addition,a specially designed path dataset,including straight and curved paths,is established to simulate various sailing scenarios so that the reinforcement learning controller can obtain as much handling experience as possible.Extensive numerical simulation results demonstrate that the proposed method has better control performance under missions involving complex maneuvers than trained with limited scenarios and can potentially be applied in practice.

Knowledge,perceptions,and practice towards adverse events following immunization surveillance among vaccination workers in Zhejiang province,China

Objective:To access the level of knowledge,perceptions,and practice towards adverse events following immunization(AEFI)surveillance among vaccination workers in Zhejiang province,China.Methods:This was a cross-sectional survey involving 768 vaccination workers.Data were collected using self-administered questionnaires and analyzed by using SAS 9.3 software.Knowledge,perceptions,and practice on AEFI surveillance were summarized using frequency tables.The mean±SD value was used as the cut-off for defining good(values≥mean)and poor(values<mean)knowledge,perceptions or practice.Binary logistic regression analysis was used to determine sociodemographic variables associated with knowledge,perceptions,and practice towards AEFI.Results:The proportions of good knowledge,perceptions and practice on AEFI surveillance were 78.13%,57.81%and 66.15%,respectively.Having a higher education background,longer years of experience,previous training on AEFI and≥30 years of age were factors associated with good knowledge,perceptions and practice on AEFI surveillance among vaccination workers.Conclusions:Over half of the respondents had good knowledge,perceptions and practice on AEFI surveillance work.Interventions on improving the vaccination workers’knowledge,perceptions and practice on AEFI surveillance should be considered in order to develop a more effective surveillance system.

Investigating the characteristic delay time in the leader–follower behavior in children single-file movement

The single-file movement experiment offered a convenient way to investigate the one-dimensional leader–follower behavior of pedestrians. This study investigated the time delays of children pedestrians in the leader–follower behavior by introducing a time-dependent delayed speed correlation. A total of 118 German students from the fifth grade(aged11–12 years old) and the 11th grade(aged 17–18 years old) participated the single-file experiment. The characteristic delay time for each pedestrian was identified by optimising the time-dependent delayed speed correlation. The influences of the curvature of the experimental scenario, density, age, and gender on the delay time were statistically examined. The results suggested that to a large extent, the revealed characteristic delay time was a density-dependent variable, and none of the curvatures, the age and gender of the individual, and the age and gender of the leader had a significant influence on it. The findings from this study are variable resources to understand the leader–follower behavior among children pedestrians and to build related simulation models.

Trade credit financing for supply chain coordination under financial challenges:a multi‑leader–follower game approach

This study is designed to solve supply chain inefficiencies caused by some members’financial problems,such as capital shortages and financing restrictions in a stochastic environment.To this end,we have established a supply chain finance framework by designing two novel coordinating contracts based on trade credit financing for different problem settings.These contracts are modeled in the form of multi-leader Stackelberg games that address horizontal and vertical competition in a supply chain consisting of multiple suppliers and a financially constrained manufacturer.However,previous studies in the trade credit literature have addressed only simple vertical competition,that is,seller-buyer competition.To solve the proposed models,two algorithms were developed by combining population-based metaheuristics,the Nash-domination concept,and the Nikaido-Isoda function.The results demonstrate that the proposed supply chain finance framework can eliminate supply chain inefficiencies and make a large profit for suppliers,as well as the financially constrained manufacturer.Furthermore,the results of the contracts’analysis showed that if the manufacturer is required to settle its payments to suppliers before the end of the period,the trade credit contract cannot coordinate the supply chain because of a lack of incentive for suppliers.However,if the manufacturer is allowed to extend its payments to the end of the period,the proposed trade credit financing contract can coordinate the supply chain.Finally,the sensitivity analysis results indicate that the worse the financial status of the manufacturer,the more bargaining power suppliers have in determining the contract parameters for more profit.

综合心理行为护理对后续精神分裂症患者负性情绪和认知功能的影响

目的:探讨综合心理行为护理对精神分裂症后续情绪行为反应和功能情况的影响。方法:选择2022年10月1日~2023年11月30日收治的248例精神分裂症患者,根据随机数字表法分为对照组和研究组各124例,两组均按照医嘱服用药物治疗,对照组采用常规护理,研究组采用综合心理行为护理;比较两组护理前后认知功能[采用MATRICS共识认知成套测验(MCCB)]、负性情绪[采用焦虑自评量表(SAS)、抑郁自评量表(SDS)],患者对护理的满意度。结果:护理后,研究组MCCB中语言流畅性、连线、数字序列、空间广度、语言记忆、持续操作管理、情绪管理维度均高于护理前(P<0.01,P<0.05),对照组语言流畅性、连线、数字序列、空间广度、持续操作管理、情绪管理维度评分均高于护理前(P<0.01,P<0.05),研究组语言流畅性、连线、数字序列、空间广度、语言记忆、视觉记忆、持续操作管理、情绪管理维度评分均高于对照组(P<0.01,P<0.05);护理后,两组SDS、SAS评分均低于护理前(P<0.01),且研究组低于对照组(P<0.01);研究组患者对护理的满意度高于对照组(P<0.01)。结论:综合心理行为护理对后续神经分裂症患者负性情绪、认知功能均具有改善作用,提高患者对护理的满意度。

新疆某健康体检机构重要异常结果分析与随访结果研究

目的研究新疆某健康体检机构重要异常结果人群分布特征及随访结果。方法选取2022年在新疆医科大学健康管理中心参加健康体检的受检者65045例,检出4665例有重要异常结果的受检者,制定重要异常结果A类B类随访规则,进行电话通知及1月、6月随访,使用随访信息系统进行提醒及表单记录。结果4665例重要异常结果受检者中A类重要异常结果447例(9.58%),B类4218例(90.42%);男性2815例(60.34%)、女性1850例(39.66%),男性高于女性(P<0.05);年龄与重要异常结果存在相关性(P<0.05);41~50岁(1114例)、51~60岁(1211例)这两个年龄段重要段异常结果人数占比高。有效通知4457例(95.54%),通知后有效随访4397例(98.65%),失访60例(1.35%);电话随访后就诊2118例(48.17%),未就诊2279例(51.83%);未就诊男性1562(58.57%)高于女性717(41.45%),性别与是否就诊有统计学意义(P<0.05)。就诊后非肿瘤性疾病1194例(56.40%),恶性肿瘤性疾病97例(4.5%),未明确827例(39.1%)。结论重要异常结果男性高于女性,随年龄增长重要异常结果发生率增高。随访路径实施中通知及随访成功率还应提高。受检者对重要异常结果指标理解不够及重视程度不高(60.44%),未按随访建议进行及时就诊,需加强健康宣教提高其健康意识,督促其重视及时治疗,对提高疾病“早筛查,早评估,早干预”有重要意义。

基于数据驱动的快速路合流区加速车道长度的研究

设计长度合理的加速车道能有效地缓解快速路合流区频繁出现的交通瓶颈问题,因此采用数据驱动方法对快速路合流区的加速车道长度进行研究。利用无人机设备测取了快速路合流区的交通数据,从交通流特性及车辆汇入行为这两个角度对实测数据进行分析,得到了合流区车辆的驾驶行为;根据合流区交通流特点,对数据集进行聚类分析,使用生成对抗式网络训练不同合流区汇入行为车辆的跟驰换道模型,并与实测数据和SUMO仿真软件中内置模型进行对比分析;应用生成对抗式网络模型进行交通环境仿真,选取速度、交通密度、交通冲突率指标建立奖励评价函数,得出了加速车道长度设计的推荐值。研究结果表明:采用主线车辆提前减速和向内侧车道换道这两种手段,可实现协同换道避让匝道汇入的车辆;相比SUMO软件内置模型,生成对抗式网络模型更加贴近实际情况;仿真得出的单车道平行式加速车道长度分别在100、80、60 km/h情况下的推荐值为280、240、200 m。

基于随访系统的延续性护理干预在酒精依赖患者中的应用

目的探讨基于随访系统的延续性护理干预在酒精依赖患者中的应用效果。方法采用方便抽样法,选取2021年3月-2022年8月在我院成瘾医学科住院治疗的酒精依赖患者120例,采用随机数字表法分为对照组和干预组,各60例。对照组出院后接受常规药物治疗,干预组在对照组基础上接受为期6个月的基于随访系统的延续性护理干预。比较2组患者干预前后对酒精的渴求程度和生活质量,以及干预后1个月、3个月和6个月对酒精的依赖状态和复饮率。结果干预前,2组患者对酒精的渴求程度和生活质量比较,差异无统计学意义(P>0.05);干预后,干预组对酒精的渴求程度和生活质量显著优于对照组(P<0.05)。干预后1个月、3个月、6个月,干预组对酒精的依赖状态和复饮率均显著优于对照组(P<0.05)。结论基于随访系统的延续性护理干预能降低酒精依赖患者对酒精的渴求和依赖程度,降低复饮率,改善患者生活质量,为酒精依赖患者院外康复管理提供了新的护理理念及干预方法。

Precious Scrolls of Chinese Devout Women Buddhist Followers:A Case Study of Wilt Idema’s Pitfalls of Piety for Married Women

Deeply-rooted in China’s popular culture,precious scrolls(Baojuan)are the golden material to display popular religious belief of the mass.Based on the rare texts sorted and annotated by Shang Lixin,Dutch Sinologist Wilt L.Idema continues his journey of translating precious scrolls.Focused on the theme of devoted women Buddhist followers in Ming dynasty,he explores the ethical choices of married women in facing the betrayal of servants or concubines.His translations not only add important reading material to Western readers in the field of Chinese popular literature,but also set standard for the coming translators in rendering Chinese ballads.

Follow-Up Care of HIV-Positive Pregnant Women in North Central Nigerian: A 15-Year Review

Background: Pregnant women bear the greatest burden of people living with HIV in the West Africa sub-region, and the country requires continuous optimal follow-up care for their disease after delivery. Documentation of such very important services is rarely done in this high-burden environment, and hence the present study. Method: A 15-year retrospective review of medical records of HIV-positive pregnant women who attended antenatal care services from January 2006 to December 2020 at the prevention of the mothers-to-child transmission unit of the health facility was carried out to document the HIV service provided at the unit, and the follow-up care at the adult HIV special treatment clinic for the continuation of their HIV treatment. Results: Of the 1245 HIV-positive pregnant mothers reviewed during the period, 702 (56.4%) were between the ages of 26 - 35 years, 1043 (83.8%) were on HIV treatment before their index pregnancy, 202 (16.2%) were diagnosed of HIV infection during their last trimester and labor, while 878 (70.5%) continued their HIV services at adult HIV special treatment clinic after delivery. The predictors of continuous care include: maternal parity with [OR] 0.51 (0.35 - 0.73), p = 0.02, time of presentation in trimester with [OR] 1.54 (1.15 - 2.06), p = 0.003, duration on antiretroviral therapy [OR] 2.14 (1.57 - 2.9) p Conclusion: The high rate of optimal follow-up care of HIV-positive mothers after delivery in the adult special treatment clinic in this study speaks of the preparedness and good supportive services provided to these mothers in the health facility. However, the high rate of loss to follow-up among this cohort of women requires a more focused intervention during their postpartum period for a better outcome.

Determinants of the Ophthalmological Follow-Up of Sickle Cell Patients at the National Center of Research and Care for Sickle Cell Patients in Lome-Togo

Objectives: To assess the factors influencing the ophthalmological follow-up of sickle cell patients in Togo. Materials and Methods: The national center of research and care for sickle cell patients (CNRSD) served as study setting. It was a descriptive and analytical study by interview over a three-month period from December 01, 2020 to March 02, 2021. Was included in the study, any patient with sickle cell disease genotype SS or SC, age ≥ 17 years, regularly followed at the CNRSD and having accepted the interview by a survey sheet. Excluded were patients with sickle cell trait genotype AS or AC or with a disability that prevented them from being interviewed. Results: Two hundred and fifty (250) patients with sickle cell disease were interviewed. The mean age was 29.1 years ± 11.12 years [17 years;67 years] and the sex ratio = 0.52. Nine patients over ten (9/10) attended at least secondary school. The jobless represented 25.60% of the total population followed respectively by students and laborers in 20.40% and 16% of cases. Twenty-four percent (24%) of patients were followed up in ophthalmology department. Statistically, there was no significant relationship between level of education (p = 0.4083), occupation (p = 0.6441) and knowledge of the ocular complications of sickle cell disease. Statistically, there was a significant relationship between knowledge of the ocular complications of sickle cell disease and compliance with ophthalmological follow-up (p = 0.0009). Conclusion: The knowledge of eye disorders related to sickle cell disease by patients with sickle cell disease improves their ophthalmological follow-up. Greater awareness on eye disorders related to sickle cell disease by medical staff towards patients with sickle cell disease would improve ophthalmological follow-up. .

Postpartum Intrauterine Device: Use and Follow-Up of Users in the Maternity Ward of the Ratoma Communal Medical Center in Conakry, Guinea

Objective: The aim of this study was to describe the use of the postpartum intrauterine device in the maternity ward of the Ratoma communal medical center in Conakry. Methods: This was a descriptive cross-sectional study carried out between July 1st 2015 and June 30 2016, i.e. a duration of one year. Results: A total of 551 patients received advice on various contraceptive methods. Most of this advice was given in the post-partum period (40.2%) and during antenatal care (39.1%). Of the patients advised, 87 (15.8%) used the intrauterine device. The majority of users (93%) were married and uneducated (63.2%), and 39.1% were poor. The majority (56.3%) of intra-uterine devices were inserted in the immediate post-partum period. The majority of women had no adverse events either during the first six weeks (n = 57;65.5%) or at 3rd months (n = 75;86.2%) or 6th months (n = 76;87.4%) after IUD insertion. Most users remained complication-free throughout the follow-up period (n = 76;87.4% at 6th weeks and 3rd months, and n = 77;88.5% at 6th months). The continuation rate was 89.7% at 6 weeks and 3rd months, and 87.4% at 6th months after insertion. The majority of users (87.0%) were satisfied with the care they received. Conclusion: This study showed very few complications among intrauterine device users, and high continuation and satisfaction rates. The intrauterine device is a long-acting, effective, reversible and safe contraceptive that can be used by most women for birth spacing in Guinea, where women do not regularly visit health facilities.

Evolution of HBV Viral Load during Clinical and Biological Follow-Up of Chronic Hepatitis B Patients at the Saint Camille Hospital in Ouagadougou

Hepatitis B virus (HBV) infection is a major public health problem worldwide. The aim of this study was to document the dynamics of HBV viral load during the follow-up of chronic hepatitis B patients at the Saint Camille Hospital in Ouagadougou (HOSCO) from 2017 to 2021. This descriptive retrospective study was carried out in the Hepato-Gastro-Enterology Department of HOSCO and focused on patients who were undergoing treatment for chronic viral hepatitis B. A total of 260 cases of chronic hepatitis B were included in the study. The most affected age group was 21 to 30 years, accounting for 48.08% of the cases. Lifestyle factors included alcohol consumption (3.08%) and tobacco use (2.69%). Major risk factors for transmission included lack of vaccination (98.46%), family history of HBV infection (68.00%) and engagement in high-risk activities (28.00%). Patients requiring treatment were prescribed Tenofovir 300 mg tablets. FibroScan® showed the presence of stage F3-F4 fibrosis (2.14%) and S3 steatosis (13.33%). After one year of follow-up, 6.92% of patients achieved an undetectable viral load with normalized transaminase levels. The majority of other patients had a detectable viral load but below 20,000 IU/mL. The prevalence of viral hepatitis B remains significant worldwide. Although effective and well-monitored treatment can lead to undetectable viremia, prevention remains the most effective strategy for successful management of this disease.

Adult Congenital Lumbar Kyphosis Requiring Anteroposterior Correction and Fusion: A Case Report with 32-Year Follow-Up

Congenital pure kyphosis due to failure of vertebral body segmentation is a relatively rare entity, and surgical intervention is infrequent compared to that for failure of vertebral body formation [1] [2]. There are very few reports of long-term follow-up of surgical treatment in patients with congenital pure kyphosis, and all the reported cases were diagnosed as failure of formation and had an age at the time of surgery of less than 18 years. It is important for orthopedic surgeons to follow the postoperative course of rare cases over 30 years. Here, we present a surgically treated case with ultra-long term follow-up of a 50-year-old patient with congenital pure kyphosis of the lumbar spine. Imaging of the lumbar spine showed six vertebrae and an unsegmented bar at L3-4 causing a pure kyphosis of 54°. The wedge-shaped block vertebra had 4 pedicles with the neural foramen between the pedicles without concomitant disc space, with compensatory thoracic hypokyphosis and lower lumbar hyperlordosis. One-stage correction and fusion surgery using anterior opening and posterior closing osteotomy was successfully performed. Both clinical and radiographic results were excellent and have been maintained for over 30 years postoperatively. The basic principle in the surgical treatment of adult spinal deformity is to achieve and maintain a good global sagittal balance over time. This case reaffirms the importance of spinopelvic harmony.