Research on modeling and self-excited vibration mechanism in magnetic levitation-collision interface coupling system

The modeling and self-excited vibration mechanism in the magnetic levitation-collision interface coupling system are investigated.The effects of the control and interface parameters on the system's stability are analyzed.The frequency range of self-excited vibrations is investigated from the energy point of view.The phenomenon of self-excited vibrations is elaborated with the phase trajectory.The corresponding control strategies are briefly analyzed with respect to the vibration mechanism.The results show that when the levitation objects collide with the mechanical interface,the system's vibration frequency becomes larger with the decrease in the collision gap;when the vibration frequency exceeds the critical frequency,the electromagnetic system continues to provide energy to the system,and the collision interface continuously dissipates energy so that the system enters the self-excited vibration state.

Experimental and Numerical Evaluation of the Cavitation Performances of Self-Excited Oscillating Jets

Self-excited oscillating jets(SOJ)are used in several practical applications.Their performances are significantly affected by structural parameters and the target distance.In this study,a geometric model of the SOJ nozzle accounting for multiple structural parameters is introduced,then the related cavitation performances and the optimal target distance are investigated using a Large-Eddy Simulation(LES)approach.Results are also provided about an experiment,which was conducted to validate the simulation results.By analyzing the evolution of the vapor volume fraction at the nozzle outlet,a discussion is presented about the effect of the aforementioned structural parameters on the cavitation performances and the target distance.It is shown that the distribution of cavitation clouds at the outlet of the SOJ nozzle displays a non-monotonic trend(first increasing,then decreasing).Under working conditions with an inlet pressure of 4 MPa,a SOJ nozzle outlet/inlet diameter ratio(D_(1)/D_(2))of 1.2,and a chamber diameter ratio(D/L)close to 1.8,the nozzle outlet cavitation performance attains a maximum.The optimal structural parameters correspond to the optimal target distance,which is near 50 mm.The experiments have revealed that the SOJ nozzle with the above parameters displays a good cavitation erosion effect at the target distance of 50 mm,in satisfactory agreement with the numerical simulation results.

Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment

The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery.

基于Altair Inspire的四旋翼无人机机身部件轻量化设计方法

无人机的续航能力是其性能优劣的一个重要指标,而影响续航的最主要因素是机身的质量,为了减轻无人机机身部件质量,利用Altair Inspire轻量化设计软件,对一种四旋翼无人机机身部件进行拓扑优化,几何重构、强度校核、并自动拟合重构得到优化模型,优化后的该模型仍存在一些缺陷,最后通过手动拟合重构得到进一步优化,达到在强度、最大位移和最小安全系数满足条件的情况下,尽可能减轻模型的质量,以达到轻量化的设计目的。结果表明,在满足强度、最大位移和最小安全系数要求的条件下,实现了71.8%的减重,有效减轻了质量,提高了无人机的续航能力,为无人机的轻量化设计提供了一种可行的方法。

Dynamical analysis and anti-synchronization of a new 6D model with self-excited attractors

A novel 6D dissipative model with an unstable equilibrium point is introduced herein.Some of the dynamic characteristics of the proposed model were explored via analyses and numerical simulations including critical points,stability,Lyapunov exponents,time phase portraits,and circuit implementation.Also,anti-synchronization phenomena were implemented on the new system.Firstly,the error dynamics is found.Then,four different controllers are adopted to stabilize this error relying on the nonlinear control technique with two main ways:linearization and Lyapunov stability theory.In comparison with previous works,the present controllers realize anti-synchronization based on another method/linearization method.Finally,a comparison between the two ways was made.The simulation results show the effectiveness and accuracy of the first analytical strategy.

Inspiration and Innovative Approach in Creating Textile Designs and Prints from Sekondi-Takoradi’s Masquerade Costume Designs

Masquerade culture is an essential part of Sekondi-Takoradi cultural embodiment. The masquerade festival titled Ankos displays interesting costumes that have artistic elements of potent colour display and performances. The masquerade costumes manifest intricate fabric decoration techniques for example pleating, folding, gathering, smocking, hand and machine stitching and the use of varied colour schemes. These decorative techniques make costume production laborious, tedious and downtime constraints. In contributing to the innovative approaches to creating textile designs and prints, the study explored the inspirational possibilities of surface designs of the masquerade costume for textile designs and prints. The art-based research design and direct observation as research instrumentation were employed in the artistic creation for the study. Adobe Photoshop was used in the simulation design processes. The study revealed that the simulation design processes produced an innovative imitated visual appearance of the masquerade costume and production processes from a machine-stitched work to a hand-printed fabric. It is recommended that costume makers adopt the contemporary possibility of using hand screen to print hitherto the traditional laborious and tedious process of producing masquerade costumes.

Impact frequency variation of self-excited oscillation pulsed supercritical carbon dioxide jets

In order to obtain the impact frequency of resonant coal breaking by self-excited oscillation pulsed supercritical carbon dioxide(SC-CO_(2))jet,large eddy simulation was used to analyze the formation and development process of self-excited oscillation pulsed SC-CO_(2)jet,the variation of jet impact frequency in the nozzle and the free flow field,and the variation of jet impact frequency at different positions in the jet axis and under different cavity lengths.The test device of jet impact frequency was developed,and experiments were performed to verify the conclusions of the numerical simulations.The results show that the frequency of the self-excited oscillation pulsed SC-CO_(2)jet is different in the nozzle and the free flow field.In the nozzle,the frequency generated by the fluid disturbance is the same,and the jet frequency at the exit of the nozzle is consistent with that inside the nozzle.In the free flow field,due to the compressibility of CO_(2),the pressure,velocity and other parameters of SC-CO_(2)jets have obvious fluctuation patterns.This feature causes the impact frequency of the self-excited oscillation pulsed SC-CO_(2)jet to decrease gradually in the axis.Changing the cavity length allows the adjustment of the jet impact frequency in the free flow field by affecting the disturbance frequency of the self-excited oscillation pulsed SC-CO_(2)jet inside the nozzle.

基于Inspire软件的汽车减震器结构轻量化设计

在现代汽车工业中,悬挂系统的性能直接关联到行车的平稳性与舒适性,而减震器作为其核心组件,在减少震动、提升乘坐体验方面发挥着至关重要的作用。文章借助Inspire软件和拓扑优化技术,在优化步骤中引入了反馈机制以实现设计过程的动态调整,同时设计一套三阶段方案的筛选流程,保证对减震器结构进行高效且有效的轻量化设计,从而提升减震器设计的性能与材料利用率。通过控制变量法探索不同方案下最优的轻量化设计为汽车减震器的创新及设计提供了可行方案。

从“烟士披里纯”到“灵感”——汉语语境中“inspiration”的译介与变异

由于不同文化语境的影响,外来语词在进入汉语语境的过程中总是会伴随着各式的“变异”情形,“inspiration”在译介中的语义演化即是典型的例证。日语的“インスピレーション”音译沿用的是英语对该词本有的古希腊-拉丁语语义的转义,梁启超的汉语音译“烟士披里纯”虽隐含了“人人可得/天才独具”的潜在矛盾,却为其在汉语语境中的重新解释预留了开阔的空间;“灵感”的定译在祛除“神/灵”的神秘性的同时,逐步实现了其与中国传统文化中“感兴”等范畴的对接与转换。对于“灵感”的心理生成机制及其现实生活来源的探究,最终构建起了“灵感”作为文艺理论专门术语的基本知识模型。寻绎这一概念的译介流脉,目的不在于订正“词义”;概念意蕴的流变,本身就隐含着衍生出新的思想与学术的诸多可能。

基于Inspire的新能源汽车轮毂轻量化设计

新能源汽车的轻量化设计旨在减少汽车的整体重量,提高新能源汽车的能源利用效率,增加行驶里程,是实现其长期发展的重要途径。本文利用Solidworks建立新能源汽车轮毂模型,在分析其实际受力情况的基础上,运用Altair Inspire软件以最大化刚度为目标对其进行轻量化设计,得到三种不同设计方案的位移、安全系数和米塞斯等效应力值,对比分析优缺点后,选取最佳优化设计方案。优化分析结果显示,轮毂质量为7.409,较优化前减轻了10.2%,在满足轮毂强度要求和安全性的前提下,实现了轮毂的轻量化,为后续优化设计提供了参考。

Application of Deep Inspiration Breath Hold Technique in Radiotherapy After Breast- Conserving Surgery for Left Breast Cancer and Its Improvement on Cardiac Dose

Objective:To analyze the application of deep inspiration breath hold technique in radiotherapy after breast-conserving surgery for left breast cancer and the improvement of cardiac dose.Methods:A total of 45 patients with left breast cancer treated in our hospital after breast-conserving surgery were selected,and the selection time was set from January 2020 to August 2022.All patients received radiotherapy.The right breast,heart,and lung volumes,and dose parameters of the heart,lungs,right breast,and left anterior descending coronary artery were compared under free breathing(FB)and deep inspiration breath hold(DIBH)technical modes.Results:The heart volume of the DIBH group was smaller than that of the FB group,and the left and right lung volumes were significantly larger than those of the FB group.In the DIBH group,the heart dose parameters V5,proper lung dose parameters,and left anterior descending coronary artery dose parameters were found lower than that of the FB group,and the differences were statistically significant(P<0.05).Conclusion:Compared with FB,the DIBH technique can reduce the heart’s size and increase the lung volume when used for radiotherapy after breast-conserving surgery for left breast cancer.It also reduces the dose to the heart,right lung,and left anterior descending coronary artery,thus protecting the heart and lungs.

Adaptive Network Sustainability and Defense Based on Artificial Bees Colony Optimization Algorithm for Nature Inspired Cyber Security

Cyber Defense is becoming a major issue for every organization to keep business continuity intact.The presented paper explores the effectiveness of a meta-heuristic optimization algorithm-Artificial Bees Colony Algorithm(ABC)as an Nature Inspired Cyber Security mechanism to achieve adaptive defense.It experiments on the Denial-Of-Service attack scenarios which involves limiting the traffic flow for each node.Businesses today have adapted their service distribution models to include the use of the Internet,allowing them to effectively manage and interact with their customer data.This shift has created an increased reliance on online services to store vast amounts of confidential customer data,meaning any disruption or outage of these services could be disastrous for the business,leaving them without the knowledge to serve their customers.Adversaries can exploit such an event to gain unauthorized access to the confidential data of the customers.The proposed algorithm utilizes an Adaptive Defense approach to continuously select nodes that could present characteristics of a probable malicious entity.For any changes in network parameters,the cluster of nodes is selected in the prepared solution set as a probable malicious node and the traffic rate with the ratio of packet delivery is managed with respect to the properties of normal nodes to deliver a disaster recovery plan for potential businesses.

基于Inspire的采摘机械臂结构优化设计

【目的】现有油茶采摘机的机械臂普遍存在设计冗杂且自重较大的问题,导致整体体积过大而无法在低矮的林区间隙穿行,亟需进一步推进采摘机械小型化、轻量化发展。【方法】以采摘机械臂的主臂为研究对象,从材料选型和结构优化两方面进行轻量化研究,以最大化刚度为设计目标,采用Altair Inspire软件的OptiStruct拓扑优化求解器,分析主臂零件的载荷工况和受力约束,对设计空间内的材料重新布局。【结果】1)铝合金材料的优化重构模型质量减轻了32%。2)优化后主臂的最大米塞斯应力为7.770 MPa,最大位移为0.07091 mm,虽然这两个参数有稍许提高,但仍远小于材料的屈服应力,且安全系数仍在较高水平。【结论】优化效果显著,有效地降低了零件的重量和成本,提高了零件的强度和耐用度,进一步提高了采摘机械臂的结构效益和经济效益。

基于Altair Inspire的飞机襟翼支架轻量化优化设计

飞机襟翼支架是与其机翼连接的重要运动部件,为优化飞机襟翼支架结构,运用Altair Inspire软件对襟翼支架进行轻量化设计。在满足飞机机翼使用性能的条件下选用襟翼支架的材料为AL2014-AREO,依据10%、15%、30%体积约束目标下襟翼支架的优化结果,通过Poly NURBS自动拟合和手动拟合对优化模型进行几何重构与强度校核,得到最优轻量化模型。优化后的飞机襟翼支架的质量为46.31 g,比优化前下降了77.59%,极大地减轻了飞机襟翼结构的整体质量,并且优化后飞机襟翼支架的位移量、安全系数、米塞斯等效应力均符合设计要求。该研究为飞机襟翼支架的设计与改进提供了一种新思路。

Inspiration功能特点及其在教学中的应用

Inspiration作为一种简单易用的概念图创作软件,目前还没有广泛的推广开来,本文首先介绍了概念图的涵义和概念图软件Inspiration的主要功能特点,然后详细说明了Inspiration在实际教学中的具体应用,即它可以作为记录和整理集体思维过程的工具、培养发散思维和创新思维的工具、进行建构主义教学的支架和教学评价的工具。

利用Inspiration培养学生创造性思维

素质教育、创新教育强调对学习者的创造性思维能力的培养,利用现代化的教学辅助工具是通向此目标的途径之一。本文结合教学实例,介绍优秀的教学辅助软件In-spiration的主要功能及特点,探讨它在对培养学习者创造性思维方面的价值,并提出在教学中的使用建议。

Inspiration在网络课程站点规划中的应用

介绍利用概念图软件Inspiration作为超文本网站结构设计的工具,帮助教师方便快捷地规划网络课程网站,它改变了以往线性脚本式的网站规划方法,很好地实现了教师与网页技术人员之间的有效协作,为网站的规划与网络课程的开发提供了方法与技术支持.

概念图软件Inspiration功能特点及其在教学中的应用

Inspiration作为一种简单易用的概念图创作软件，目前还没有广泛推广开来，本文首先介绍了概念图的涵义和概念图软件Inspiration的主要功能特点，然后详细说明了Inspiration在实际教学中的具体应用，即它可以作为记录和整理集体思维过程的工具、培养发散思维和创新思维的工具、进行建构主义教学的支架和教学评价的工具。

概念图软件Inspiration功能特点及其在教学中的应用

本文介绍了概念图的涵义和概念图软件Inspiration的主要功能特点,详细说明了Inspiration在实际教学中的具体应用,即它可以作为记录和整理集体思维过程的工具、培养发散思维和创新思维的工具、进行建构主义教学的支架和教学评价的工具。

概念图及其软件Inspiration在教学中的应用

本文在简要介绍概念图相关知识背景的基础上，结合一线教学实例，论述了概念图及其软件平台Inspiration在教学中的应用方式与积极影响。