Inflection point identifying of weld seam based on force sensing in tele-teaching

Weld seam inflection points are inevitable in tele-teaching process on many welding occasions. The inflection points identified accurately is one of the prerequisites of ensuring tele-teaching precision. On the basis of the inflection point characters, the concept of inflection point direction coefficient is proposed, the human-simulation intelligent control model of inflection point is established. The algorithms above, the inflection point identifying of box workpiece can be well performed. The experimental results show that the identifying average error of inflection point can be reduced to less than O. 5 mm by using optimal treatment of robot off-line programming system. The identifying control can automatically identify weld seam inflection points which can meet tele-teaching requirements.

Plane Elasticity and Dislocation of One-Dimensional Hexagonal Quasicrystals with Point Group 6

Plane elasticity theory of one-dimensional hexagonal quasicrystals with point group 6 is proposed and established. As an application of this theory, one typical example of dislocation problem in the quasicrystals is investigated and its exact analytic solution is presented. The result obtained indicates that the stress components of (elastic) fields of a straight dislocation in the quasicrystals still first order singularity, which is the same as the (general crystals,) but are related with the Burgers vector of phason fields, which is different from the general (crystals.)

基于Point-to-Plane ICP的点云与影像数据自动配准

针对三维激光点云与二维影像数据的融合问题,采用了一种基于Point-to-Plane ICP的配准方法;该方法仅采用一块普通的平面黑白棋盘格作为标定板,能同时完成单目相机的标定与三维激光扫描仪和相机的联合标定,进而实现三维点云数据与二维影像数据的配准;与以往基于控制点或者边缘对应的配准方法不同,该方法使用RANSAC算法自动提取场景中的标定平面,通过优化点到平面的距离来求取两组数据的变换。实验结果表明,该配准方法减少了人工的干预,并获得了很高的精度。

Research on Algorithm of the Point Set in the Plane Based on Delaunay Triangulation

In the paper, an improved algorithm is presented for Delaunay triangulation of the point-set in the plain. Based on the original algorithm, we propose the notion of removing circle. During the process of triangulation, and the circle dynamically moves, the algorithm which is simple and practical, therefore evidently accelerates the process of searching a new point, while generating a new triangle. Then it shows the effect of the algorithm in the finite element mesh.

Research on the Arrangement of Dew Point Temperature Detectors of Capillary Plane Radiation Air-Conditioning

Based on analysis of the reason and process of condensation on ceiling radiant cooling panels, two kinds of arrangement of detectors are put forward. The physical model is established, the results show that detectors are arranged as the form of triangle is more suitable. It can not only satisfy the use requirement but also it is economical and practical. Finally we can conclude that the inlet water temperature 0.5°C higher than dew point temperature is safe and reliable.

Instantaneous Point, Line, and Plane Motions Using a Clifford Algebra

The motions of points, lines, and planes, embedded in a rigid body are expressed in a unified algebraic framework using a Clifford algebra. A Clifford algebra based displacement operator is addressed and its higher derivatives from which the coordinate-independent characteristic numbers with simple geometric meaning are defined. Because of the coordinate independent feature, no tedious coordinate transformation typically found in the conventional instantaneous invariants methods is needed.

A Graded and Individualized Teaching and Learning method

Taking the programming course as an example,a comprehensive solution for individualized and precise teaching has been proposed.Firstly,graded teaching strategy is performed.The students are divided into three groups according to their base of learning and the degree of acceptance of knowledge.Designed teaching resources are provided for the teaching mode of low starting points and high landing points.Secondly,a process evaluation method combining online and offline has been proposed.An“evaluation-feedback-improvement”mechanism based on the analysis of students’learning data has been adopted.The practice in Harbin Institute of Technology has shown that the proposed method can not only help students achieve individualized learning goals,but also help teachers achieve precise teaching.

Power Generation Expansion Planning Using an Interior Point with Cutting Plane （IP/CP） Method

The generation expansion planning is one of complex mixed-integer optimization problems, which involves a large number of continuous or discrete decision variables and constraints. In this paper, an interior point with cutting plane （IP/CP） method is proposed to solve the mixed-integer optimization problem of the electrical power generation expansion planning. The IP/CP method could improve the overall efficiency of the solution and reduce the computational time. Proposed method is combined with the Bender＇s decomposition technique in order to decompose the generation expansion problem into a master investment problem and a slave operational problem. The numerical example is presented to compare with the effectiveness of the proposed algorithm.

Towards an Antimicrobial Stewardship Program in a Young Tertiary Hospital in Southern Nigeria: A Point Prevalence Survey of Antimicrobial Usage

Background: Antimicrobial resistance (AMR) is one of the top 10 global public health threats facing humanity and this burden is borne largely by low and middle-income countries. As part of efforts to combat AMR, the World Health Organization has identified Antimicrobial Stewardship as one of the strategic objectives of its global action plan on antimicrobial resistance. This survey aimed to observe antimicrobial prescribing and usage patterns in the Rivers State University Teaching Hospital with the purpose of identifying gaps to inform the specific antimicrobial stewardship interventions necessary to address our specific needs. Methodology: A point prevalence survey was conducted using the protocol and web-based automated data management system designed by the Global Point Prevalence Survey of Antimicrobial Consumption and Resistance, University of Antwerp, Belgium, in November 2021. Results: A total of 69 adult medical and surgical patients were surveyed;27 males and 18 females. Antimicrobial prevalence was 65.2%. Third generation cephalosporins (24.4%;33.3%), fluoroquinolones (17.8%;22.2%) and imidazole derivatives (20%;36.1%) were most prescribed on the medical and surgical wards. Antimicrobial guidelines were completely unavailable, most antimicrobials (93.8%) were prescribed empirically and 64.4% of these remained empirical after 72 hours of commencement. Conclusion: Antimicrobial stewardship interventions are necessary to minimize sub-optimal antimicrobial prescribing practices in our facility. Most critical are education on appropriate use of antimicrobials, support for development of antimicrobial guidelines, diagnostic stewardship, and the drive for improved use of the laboratory to guide antimicrobial prescriptions. The antimicrobial stewardship committee and team must drive this, having the requisite support from the management and prescribers, with the primary outcomes being reduced antimicrobial prevalence and improved antimicrobial prescription patterns.

改进的3D-BoNet算法应用于点云实例分割与三维重建

为了更好地利用点云数据重建室内三维模型,本文提出了一种基于3D-BoNet-IAM算法的室内场景三维重建方法。该方法通过改进3D-BoNet算法提高点云数据的实例分割精度。针对点云数据缺失问题,提出了基于平面基元合并优化的拟合平面方法,利用拟合得到的新平面重建建筑表面模型。在S3DIS和ScanNet V2数据集上验证3D-BoNet算法的改进效果。试验结果表明,本文提出的3D-BoNet-IAM算法比原始算法分割精度提高了3.3%;对比本文建模效果与其他建模效果发现,本文方法的建模效果更准确。本文方法能够提高室内点云数据的实例分割精度,同时得到高质量的室内三维模型。

Promotive Measures Adopted in Interactive Bilingual Teaching

Quality assurance is of vital importance to bilingual education.Effective promotive measures adopted in interactive bilingual teaching including key point interaction between students and teacher in class,case teaching,stereoscopic teaching were described in detail.The assessment of bilingual education quality via weight distribution of success factors of bilingual education was proposed practically.

基于三维点云计算的CO_(2)-水-岩反应程度量化表征方法

CO_(2)地质封存是减少大气中CO_(2)排放,降低温室效应的重要途径,CO_(2)注入含水地层中时,CO_(2)-水-岩反应可能引起岩石矿物的侵蚀,对CO_(2)地质封存安全性产生显著影响。在室内实验中,通过表征岩石表面的形貌特征可以有效地评估CO_(2)-水-岩反应程度,为CO_(2)地质封存的安全性评估提供科学依据。通过三维点云计算可以精确量化地表征CO_(2)-水-岩反应程度,这种方法首先运用三维激光扫描技术,构建岩石表面的三维模型,确定CO_(2)-水处理前岩石表面三维模型的基准面,并基于处理前的均方根粗糙度确定处理后岩石表面三维模型的基准面。基于三维模型点云信息,提出了两种不同的体积计算新方法,并通过对规则模型体积的计算比较了两种计算方法的准确性与适用性,可根据实际情况选择两种计算方法量化表征CO_(2)-水处理前后岩石表面的侵蚀体积。最后,以陕西省咸阳市某煤矿煤样为例,开展了CO_(2)-水-岩反应模拟试验,验证了计算的可行性。试验结果表明:该文提出的侵蚀体积计算方法可有效地量化表征CO_(2)-水-岩反应程度,CO_(2)-水处理后岩石表面不同区域的侵蚀差异性明显,岩石表面的侵蚀体积与均方根粗糙度之间存在显著的正比关系,随着均方根粗糙度的增大,侵蚀体积也相应上升。

Design Learning Routines in Bilingual Teaching Environment

This report is written to describe at least three Learning Routines I have used and monitored which promote English as the language of instruction in bilingual teaching environment.It introduces routines for a large group(15 + students),routines for a small group(5-10 students),routine for a pair of learners,and the use of mother tongue.

基于多平面分割和矩阵变换的航摄边坡点云滤波算法

点云滤波是实现地面点与非地面点分离,获取最真实地面点云的重要处理手段,是进行公路边坡点云灾害识别的基础.为了克服传统点云滤波算法在边坡场景下处理速度慢、结果精度低和误差大等问题,提出了基于多平面分割和矩阵变换的航摄边坡点云滤波算法.该方法首先利用基于曲率的区域生长算法对边坡进行多平面分割,得到多个边坡子点云;其次拟合得到边坡子点云平面模型,再利用旋转矩阵将边坡子点云进行空间转换至水平面;然后通过模拟布料下沉并设置距离阈值分离出非地面点;最后再次利用旋转矩阵的逆矩阵进行空间位置还原,进而得到滤波后的边坡点云.利用精细贴近仿地航线设计方法获取高精度点云模型以在不同的边坡场景下进行算法测试,并与其他传统滤波算法结果进行对比,结果表明:在所有的试验中,本文算法的总误差分别为7.11%、4.15%、1.45%、4.41%,在所有测试算法中最小;Kappa系数分别为0.77、0.90、0.96、0.90,在所有测试算法中最大.本文提出的算法在面对地形和植被情况复杂的边坡情景下,有着较高的准确性以及较强的适用性,为公路边坡点云滤波提供了新的解决方案.

基于点云的航发叶片分割及打磨轨迹规划方法

针对航发叶片打磨过程中点云分割效果差和轨迹规划中曲面拟合所带来的计算量大的问题,提出了一种基于点云的航发叶片分割及打磨轨迹规划方法,旨在改善点云分割效果并降低计算量。通过结构光相机采集待打磨叶片点云,进行滤波等预处理,并对随机采样一致性(Random Sample Consensus,RANSAC)平面分割算法进行改进,提升算法效率。设计一种结合点云颜色信息的区域生长分割算法,实现叶片待打磨区域的稳定分割。提出一种直接基于点云的三重截面法,配合B样条曲线拟合算法生成预打磨轨迹,并基于等残高算法优化行距,完成打磨轨迹规划。经实验验证,平面分割算法相较于传统方法效率提升40.25%,数据处理效率大大提高。此外,通过改进的区域生长分割算法,叶片打磨轨迹规划效率得到明显提高,其实现效果显著增强。

飞行器虚拟实验平台开发及其在教学中的应用

为让学生掌握飞行器约束影响、轨迹规划及跟踪制导方法及仿真实验过程,开发飞行器虚拟仿真实验网络平台。该设计基于PostgreSQL数据库的网络平台开发方案,论述飞行器约束影响、轨迹规划和跟踪制导原理,阐述实验仿真过程、结果及在教学中的应用。通过该虚拟实验平台可显著提升学生的学习效率,提高学生的实践和动手能力。

镂空重构手法在服装设计中的创新应用

为了打破镂空工艺对材料、技术的使用界限,丰富其在服装设计中的创新应用,通过梳理服装中镂空构型的起源与发展,在镂空重构概念界定的基础上,结合已有案例归纳分析镂空重构的3类实现手法:连接点式镂空、重塑线式镂空以及剪切面式镂空。以连接点式镂空手法为例,进一步探究镂空重构手法在服装设计中的创新实践:一是镂空构型材料层面的创新,将环保理念融入服装设计,实现废弃物升级利用;二是造型表现技术层面的创新,结合立体塑形进行服装造型表现的拓展实践,并对镂空重构手法在服装设计领域的应用前景作了展望。

“电路原理”混合式智慧教学的探索与实践

“电路原理”混合式智慧教学,以学生为中心,在优化设计教学内容、系统建设教学资源的基础上,将智慧教学平台和群聊工具引入课程,构建“课前预习—课堂学习—课后评价及反馈”知识点闭环教学系统,通过线上学习与线下教学混合、课内学习与课外自学混合、群聊工具与课程教学混合、理论学习与工程应用混合,在实现教与学充分融合的同时,促进学生自主学习能力,有效提高课程的教学质量。

《内科学》教学“痛点”及应对策略

为了培养不断提升自身修养的优秀临床医师,文章探讨了《内科学》教学创新过程中的教学“痛点”及应对策略。文章旨在坚持“以学生为中心”的教学理念,根据学生学习过程中面临的实际问题,探寻痛点,结合教学创新,寻找应对策略。《内科学》在高等医学教育教学过程中发现四大“痛点”,即重外轻内、浅尝辄止、难遇罕见、学不及新。针对以上痛点,创新性地提出并践行“德以明理,笃志好学”的创新教育理念,分析对策,戳痛点、促改革。“德以明理”着重解决“重外轻内”过程中的思想问题。“笃志好学”理念着眼于解决“浅尝辄止”“难遇罕见”“学不及新”三大学习痛点。经过“戳痛点、促改革”的教学创新实践,《内科学》教学质量与教学效果显著提升。

融合思政元素的“高等数学”课程设计与实践——以曲线拐点教学为例

探讨了如何在“高等数学”教育中将思想政治教育融入课堂教学,并以曲线拐点教学为例进行了实践和应用。“高等数学”课程作为培养学生科学素养和解决实际问题能力的关键课程,须注重学生的综合素质培养。思想政治教育的目的是培养学生的思想道德素质和社会责任感,二者的结合对学生的学习具有积极的影响。通过将曲线拐点教学与思想政治教育相结合,可以提高学生的学习兴趣和动力,培养其创新能力和实践能力,促进学科交叉和综合素养的发展。另外,从课堂引入、教学过程和结尾等方面提出了具体的教学方法和建议,以期帮助教师在“高等数学”教育中有效融入思想政治教育。