Closed-Loop System Identification Approach of the Inertial Models

The mathematical model that approximates the dynamics of the industrial process is essential for the efficient synthesis of control algorithms in industrial applications. The model of the process can be obtained according to the identification procedures in the open-loop, or in the closed-loop. In the open-loop, the identification methods are well known and offer good process approximation, which is not valid for the closed-loop identification, when the system provides the feedback output and doesn’t permit it to be identified in the open-loop. This paper offers an approach for experimental identification in the closed-loop, which supposes the approximation of the process with inertial models, with or without time delay and astatism. The coefficients are calculated based on the values of the critical transfer coefficient and period of the underdamped response of the closed-loop system with P controller, when system achieves the limit of stability. Finally, the closed-loop identification was verified by the computer simulation and the obtained results demonstrated, that the identification procedure in the closed-loop offers good results in process of estimation of the model of the process.

The remote sensing composite information of Nansha reef's closed atoll and the model of its spatial structure evolution——Ⅰ

Based on the feature of the growth and the local limitation of the Nansha reef's closed atoll, also the related remote sensing information of it, the composite analysis is made. The closed atoll conception remote sensing system is constructed through the formation mechanism, development law and the space-time distribution of the closed atoll. Solution of the equation consisting of information function value and isostatic value of closed atoll and half-closed atoll using this system, and topologic analysis on the two kinds of atoll's morphologic growth are the basic foundation for the research of their evolutionary comparative model.

An Integrated Multi-Echelon Model for a Sustainable Closed Loop Supply Chain Network Design

The integration of entire supply and value chain into a closed loop network is gaining more importance in recent times in order to ensure a business to be economically and environmentally sustainable with the changing trends in business and social environments, growing environmental consciousness in the society and government legislations to protect the environment as well as the business. In this context, this paper considers a multi-echelon closed loop supply chain network design with forward and reverse logistics components. An attempt has been made to develop a mixed integer non-linear programming model for this problem with different costs so that the sum of the total cost is minimized subject to different constraints pertaining to capacities of the entities of the system, demands of first customers and second customers. A generalized model is presented and then its application is illustrated using an example problem by solving the model using LINGO14. This model forms as a tool to compare future meta-heuristics to check the closeness of their solutions with corresponding optimal solutions.

THE SEPARATION OF LARGE VORTEXES AND THE CLOSED EQUATIONS OF TURBULENCE MODEL

This paper presents a new kind of everage for the loeally-generated large vortexes so that the physieal quantities of the locally-generated large vortexes and the external large vortexes canberigorously separated from the equal ions for the large vortexes proposed in a previous paper[1] To the equations for the two kinds of large vortexes, some auxiliary relations are introduced, and the value, of the length-scale lN of energy dissipation of the external large vortexes may he determined according to the actual circumstances of the disturbance of external sources. Thus the resulting equations of the second moments of turbulent velocity fluctuations for the two kinds of large vortexes can be made closed. Meanwhile, the corresponding coefficients of diffusion in the previous paper[1] are improved,Finally, a closed set of numerically-solvable equations of turbulence model are obtained.

Distribution of Mass and Energy in Closed Model of the Universe

The universe’s horizon distance and volume are constructed in the closed cosmic model. The universe horizon distance distribution increases constantly for t tme and decreases for t > tme. However, the universe’s horizon volume shows a sudden reduction in the range t = 0.5 Gyr - tme due to the change of the universe space from flat to curved then closed in the interval 15.1261 Gyr ≤ t ≤ tme. On the other hand, this distribution exhibits an abrupt rise in the range t = tme - t* due to the change of the universe space from closed then curved to flat in the interval 39.3822 ≤ t ≤ 40.7521 Gyr. The mass of radiation, matter and dark energy within the horizon volume of the universe are also investigated. These distributions reveal similar noticeable changes as the universe’s horizon volume distribution for the same reasons. The mass of radiation dominates up to t = 53221.5 yr, then the mass of matter becomes larger. Afterwards, both distributions of radiation and matter decrease while the distribution of dark energy rises until t = 10.1007 Gyr, where the mass of dark energy prevails up to t = tme. Hence, the distribution of dark energy reduces until t = 40.2892 Gyr, where the mass of matter becomes prominent again. At t = 53.6246 Gyr the masses of both matter and radiation become appreciably high such that the intercluster space will vanish and clusters of galaxies interfere with each other. Furthermore, not only the intergalactic medium will disappear, but also galaxies will collide and merge with each other to form extremely dense and close cosmological bodies. These very dense bodies will undergo further successive collisions and mergers under the action of central gravity, where the interstellar medium will vanish and the universe would develop to big crunch at tbc = 53.6251 Gyr. It is interesting to note that the horizon distance of the universe in the closed model at t = tme is in very good agreement with the maximum horizon distances in the five general cosmic models.

Model Reference Adaptive Control for Switched Systems with Closed-loop Reference Model Under Arbitrary Switching

This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference model and the measurable output error, adaptive laws and controllers are designed for switched systems.Each subsystem may have its individual reference model and controller, which increases the design flexibility.The introduction of the closed-loop reference model is to get a better transient performance of the whole switched systems.A numerical example is provided to verify the effectiveness of the main results.

Two-Phase Flow Modeling in a Single Closed Loop Pulsating Heat Pipes

Mathematical modeling of pulsating heat pipes through ‘first’ principles is a contemporary problem which remains quite elusive. Simplifications and assumptions made in all the modeling approaches developed so far render them unsuitable for engineering design. In this paper, a more realistic modeling scheme is presented which provides considerable try for thought toward the next progressive step. At high enough heat flux level, closed loop pulsating heat pipes experience a bulk internal unidirectional fluid circulation. Under such a condition, conventional two-phase flow modeling in capillary tubes may be applied. This has been attempted for single-loop PHPs. A homogeneous model and a separated two-fluid flow model based on simultaneous conservation of mass, momentum and energy, have been developed for an equivalent ‘open flow’ system. The model allows prediction of two-phase flow parameters in each sub-section of the device thereby providing important insights into its operation. The concept of ‘void fraction constraint’ in pulsating heat pipe operation is introduced and its relevance to future modeling attempts is outlined.

A New Mean Reversion Model of Close-End Fund

On the basis of fractal theory, one of the nonlinear theories, this paper studies the validity of Chinese fund market fractal time sequence through Hurst exponent, calculates the H value and proposes a new close-end fund mean reversion model. Meanwhile, this paper validates the mean reversion time sequence for consecutive 54 week data of fund market. The result indicates that this model can effectively prove that Chinese close-end fund market follows the biased random walk. The research also proves that the fund discount does have mean reversion tendency and averagely the fund with high discount has a higher excess yield than that of the fund with low discount. The mean excess yield and the ratio between discount rate deviation and standard deviation demonstrate a descending relationship. The optimum investment period based on ＂mean reversion＂ is one month. Consequently this model provides a new arbitrage method through the discount of close-end fund.

Changes in neurological and pathological outcomes in a modified rat spinal cord injury model with closed canal

Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively complete spinal canal.Thus,open spinal cord injury models often do not simulate real injuries,and few previous studies have investigated whether having a closed spinal canal after a primary spinal cord injury may influence secondary processes.Therefore,we aimed to assess the differences in neurological dysfunction and pathological changes between rat spinal cord injury models with closed and open spinal canals.Sprague-Dawley rats were randomly divided into three groups.In the sham group,the tunnel was expanded only,without inserting a screw into the spinal canal.In the spinal cord injury with open canal group,a screw was inserted into the spinal canal to cause spinal cord injury for 5 minutes,and then the screw was pulled out,leaving a hole in the vertebral plate.In the spinal cord injury with closed canal group,after inserting a screw into the spinal canal for 5 minutes,the screw was pulled out by approximately 1.5 mm and the flat end of the screw remained in the hole in the vertebral plate so that the spinal canal remained closed;this group was the modified model,which used a screw both to compress the spinal cord and to seal the spinal canal.At 7 days post-operation,the Basso-Beattie-Bresnahan scale was used to measure changes in neurological outcomes.Hematoxylin-eosin staining was used to assess histopathology.To evaluate the degree of local secondary hypoxia,immunohistochemical staining and western blot assays were applied to detect the expression of hypoxia-inducible factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF).Compared with the spinal cord injury with open canal group,in the closed canal group the Basso-Beattie-Bresnahan scores were lower,cell morphology was more irregular,the percentage of morphologically normal neurons was lower,the percentages of HIF-1α-and VEGF-immunoreactive cells were higher,and HIF-1αand VEGF protein expression was also higher.In conclusion,we successfully established a rat spinal cord injury model with closed canal.This model could result in more serious neurological dysfunction and histopathological changes than in open canal models.All experimental procedures were approved by the Institutional Animal Care Committee of Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine,China(approval No.HKDL201810)on January 30,2018.

Critical Behavior of the Energy Gap and Its Relation with the Berry Phase Close to the Excited State Quantum Phase Transition in the Lipkin Model

In our previous work [Phys. Rev. A 85 （2012） 044102], we studied the Berry phase of the ground state and exited states in the Lipkin model. In this work, using the Hellmann-Feynman theorem, we derive the relation between the energy gap and the Berry phase closed to the excited state quantum phase transition （ESQPT） in the Lipkin model. It is found that the energy gap is approximately linearly dependent on the Berry phase being closed to the ESQPT for large N. As a result, the critical behavior of the energy gap is similar to that of the Berry phase. In addition, we also perform a semiclassical qualitative analysis about the critical behavior of the energy gap.

闭环式管理模式对门诊癌痛患者的护理效果评价

目的探索闭环式管理模式对门诊癌痛患者的镇痛效果及可行性。方法收集2019年12月—2020年6月在江苏省肿瘤医院镇痛门诊首诊并使用阿片类药物(羟考酮缓释片)进行镇痛治疗的癌痛患者112例为研究对象。按照组间基本特征具有可比性的原则将患者分为对照组和观察组,每组56例,对照组给予常规管理;观察组接受闭环式管理模式,包括对患者首诊、复诊、定期随访、宣教、用药记录、指导等,同期疼痛门诊专科医师、药师、护士对患者制订个体化规范、合理、有效的镇痛方案及随诊计划,重点解决患者镇痛用药依从性,随诊反馈中存在的问题。两组患者均接受持续1个月的管理,记录并比较两组患者管理前后的服药依从率、数字评分量表(NRS)、爆发痛次数、疼痛控制满意程度,外周血β-内啡肽(β-EP)、前列腺素E-2(PGE-2)、内皮素-1(ET-1)、体质状况(KPS)评分,记录两组患者管理后对护理满意程度及管理期间发生的不良反应。结果管理前,两组患者的服药依从率、NRS、爆发痛次数、β-EP、PGE-2、ET-1、KPS评分比较差异均无统计学意义(P>0.05);管理后,观察组患者的服药依从率、镇痛满意程度、β-EP、护理满意程度和KPS评分高于对照组,差异均有统计学意义(P<0.05)。观察组患者的NRS、PGE-2、ET-1和不良反应发生程度均低于对照组,爆发痛次数少于对照组,差异均有统计学意义(P<0.05)。结论闭环式管理模式可有效提升门诊癌痛患者服药依从,有效控制疼痛,改善患者体质。

贴近摄影与倾斜摄影测量技术在宗教活动场所三维建模的应用

探索了贴近摄影与倾斜摄影测量技术在宗教活动场所三维建模中的应用,通过无人机平台挂载设备对场所进行采集和处理,进行多源数据融合三维建模,实现宗教活动场所的三维模型重建。本文的研究不仅为宗教活动场所的数字化保护利用和文化传承提供了新的思路和技术方法,也为其他文化遗产的数字化保护利用提供了非常有价值的参考。

差额碳税视角下应急产品闭环供应链的协调机制研究

为提高应急产品的资源利用效率并强化应急体系协同绿色发展,构造制造商处主导地位、零售商处从属地位的应急产品闭环供应链博弈模型。从差额碳税视角出发对比分析集中决策和分散决策下应急产品闭环供应链的各个均衡决策,推导出利用“讨价还价”模型实现供应链协调的条件,并进行算例分析。研究结果表明:差额碳税政策可以提高再制造应急产品的市场占比份额,促进资源的高效循环发展;讨价还价模型可以实现闭环供应链的有效协调。研究结果可为应对突发事件提供理论参考。

Subsystem model-based close-loop grey-box identification method for hydraulic stewart platform

In order to solve the problem of difficult modeling and identification caused by time-variable parameters,multiple inputs and outputs and unstable open loop,a subsystem model-based close-loop grey-box identification method was put forward when consider the main coupling effects of hydraulic Stewart platform.Firstly,the whole system is divided into three TITO(Two Input Two Output) subsystems according to the characteristics of the pseudo-mass matrix,hence transfer function matrix model of the subsystem can also be found.Secondly,since the Stewart platform is unstable,the close-loop transfer model of the subsystem is derived under the proportional controllers.The inverse M serial is adopted as the identification signal to get the experimental data.All parameters of the subsystem are determined in close-loop indirect identification by PEM(Prediction Error Method).Finally,a case study validates the correctness and effectiveness of the subsystem model-based close-loop grey-box identification method for hydraulic Stewart platform.

网红打卡点图片能刺激乡村旅游游客出游意愿吗?——“封闭代表圈”理论的验证

网红打卡点图片本质上是“封闭代表圈”理论的现实应用,已成为乡村旅游刺激游客出游意愿的重要营销手段之一。文章基于刺激—个体—反应—结果(SOBC)模型,验证“封闭代表圈”理论在乡村旅游中的适用性。基于结构方程模型的实证结果表明,该理论同样适用于乡村旅游领域,网红打卡点图片的信息量、娱乐性、兴奋度和真实性可以显著提升游客出游意愿与图片分享意愿。此外,乡村旅游目的地品牌效应与适宜距离对出游意愿具有重要作用。但是,网红打卡点图片的刺激作用在自然景观类、人文景观类与休闲活动类乡村旅游目的地中存在差异。据此,文章为乡村旅游目的地管理者的网红打卡点营销提出可行性建议。

突发事件下的封闭空间情绪传播模型研究

为避免突发事件中复杂情绪在封闭空间内无序发酵引发衍生灾害,探索封闭空间的情绪传播规律,基于情绪自发传播模型SISa,考虑封闭空间个体情绪的差异性、群体极化现象、特殊情绪交互方式以及危急情景下的动态感染率,分别改进主体情绪状态、情绪转移路径、交互模式与感染率,提出1种适用于封闭空间的情绪传播模型SE 4Sa,并以武汉地铁2号线为例完成数值仿真与敏感性分析。研究结果表明:情绪自发转移过程对限制负面情绪累积起到关键作用,且情绪极化现象使系统危险性大幅增长;缩减个体情绪感知域使系统稳定时间缩短90.6%、高唤醒负面情绪占比下降27.4%;突发事件下的动态感染率更符合封闭空间情绪传播特性。研究结果可为突发事件下封闭空间的群体行为和群体情绪规律研究提供理论支持。

架空输电线路通用型闭式卡具的研制与应用

在输电线路检修作业中,常使用闭式卡具对单片异常绝缘子进行更换。分析了闭式卡具存在的缺陷;阐述了通用型闭式卡具从设计、3D建模、选材到生产的全过程,并对实物进行了检测;随后介绍了通用型闭式卡具现场作业使用方法,并结合实际案例对应用效果进行了分析;对通用型闭式卡具的研制与应用工作进行了归纳总结,展望了推广前景,并提出了进一步改进意见。通用型闭式卡具可用于更换70~240 kN多种型号瓷质与钢化玻璃绝缘子,并将塔上作业时间较少约58%,极大地提高了作业效率。

利用智慧化管理平台实现患者护理服务体验的闭环管理

持续提升患者就医体验是进一步改善护理服务行动计划的目的。为破解传统患者体验调查方式存在的患者参与率低、问卷有效率低、测评结果无法及时反馈、测评数据无法充分利用等问题,基于技术接受模型理论和“以人为中心”的理念,设计和优化住院患者护理服务体验智慧化管理平台,通过患者体验测评短信自动触发、患者体验数据自动分析与反馈、针对性改进计划提交,实现了患者体验“测评-反馈-提升”闭环管理,改善了患者护理服务体验。

低碳视角下集成式纺织服装闭环供应链运作决策

纺织服装产业的蓬勃发展,不仅有效带动了社会经济的快速发展,同时也造成了废旧服装数量的日益剧增。为有效提高废旧服装回收效率及其利用率,兼顾供应链整体运营与生态环境的目标,文章设计分析了一个由供应商、制造商和零售商组成的三级纺织服装闭环供应链网络,其中零售商集成废旧服装的统一回收,制造商集成废旧服装的统一分类及再利用废旧服装的加工处理。鉴于服装回收处理过程中碳排放量高且分布不均这一现实问题,引入碳配额机制,以供应链整体收益和成本为目标,建立一个双目标决策优化模型,并对模型设计了约束求解方法。最后通过数值实验说明了本文所建模型的有效性和相应运营决策方案的合理最优性。相关研究结果表明:废旧纺织服装的回收处理尽管需要一定的运营成本,但从长期运营视角来看,其能够给供应链整体带来较大的潜在收益。零售商和制造商的集成化运营模式不仅可有效的降低供应链的整体运营成本,同时亦可有效提升供应链整体的协同运作效率。合理的碳配额机制可有效激励相关成员企业去绿色低碳运营,进而提升自身竞争力和可持续发展能力。相关研究成果不仅具有一定的理论价值,同时对政府和服装产业制定合理的碳配额机制,设计构建纺织服装闭环供应链网络具有一定的指导和借鉴意义。

“电力电子技术基础”闭环型教学控制模型分析与实践

自动控制原理中的反馈闭环控制结构可以消除设定值与输出值之间的误差,使输出值跟随设定值或输入值。本文给出几种单闭环或双闭环反馈型教学控制结构,在与自动控制原理中反馈闭环控制结构进行对比分析后,分析了反馈型教学控制结构的工作原理,并给出了过去反馈型教学控制获得的经验,表明反馈型教学控制结构概念清晰,互操作性强,执行效率高,可扩展性强,易于推广应用。