Comparative Studies between Picard’s and Taylor’s Methods of Numerical Solutions of First Ordinary Order Differential Equations Arising from Real-Life Problems

To solve the first-order differential equation derived from the problem of a free-falling object and the problem arising from Newton’s law of cooling, the study compares the numerical solutions obtained from Picard’s and Taylor’s series methods. We have carried out a descriptive analysis using the MATLAB software. Picard’s and Taylor’s techniques for deriving numerical solutions are both strong mathematical instruments that behave similarly. All first-order differential equations in standard form that have a constant function on the right-hand side share this similarity. As a result, we can conclude that Taylor’s approach is simpler to use, more effective, and more accurate. We will contrast Rung Kutta and Taylor’s methods in more detail in the following section.

Evaluation of IoT Measurement Solutions from a Metrology Perspective

To professionally plan and manage the development and evolution of the Internet of Things(IoT),researchers have proposed several IoT performance measurement solutions.IoT performance measurement solutions can be very valuable for managing the development and evolution of IoT systems,as they provide insights into performance issues,resource optimization,predictive maintenance,security,reliability,and user experience.However,there are several issues that can impact the accuracy and reliability of IoT performance measurements,including lack of standardization,complexity of IoT systems,scalability,data privacy,and security.While previous studies proposed several IoT measurement solutions in the literature,they did not evaluate any individual one to figure out their respective measurement strengths and weaknesses.This study provides a novel scheme for the evaluation of proposed IoT measurement solutions using a metrology-coverage evaluation based on evaluation theory,metrology principles,and software measurement best practices.This evaluation approach was employed for 12 IoT measure categories and 158 IoT measurement solutions identified in a Systematic Literature Review(SLR)from 2010 to 2021.The metrology coverage of these IoT measurement solutions was analyzed from four perspectives:across IoT categories,within each study,improvement over time,and implications for IoT practitioners and researchers.The criteria in this metrology-coverage evaluation allowed for the identification of strengths and weaknesses in the theoretical and empirical definitions of the proposed IoT measurement solutions.We found that the metrological coverage varies significantly across IoT measurement solution categories and did not show improvement over the 2010–2021 timeframe.Detailed findings can help practitioners understand the limitations of the proposed measurement solutions and choose those with stronger designs.These evaluation results can also be used by researchers to improve current IoT measurement solution designs and suggest new solutions with a stronger metrology base.

A Computational Solution of Natural Convection Flow in a Rotating Fluid with Radiative Heat Transfer

An analysis of the hydromagnetic free convective flow past a vertical infinite porous plate in a rotating fluid is carried out. The temperatures involved are assumed to be very large so that the radiative heat transfer is significant, which renders the problem very non-linear even on the assumption of a differential approximation for the radiative flux. The temperature and velocity fields are computed using a generic software tool based on the Nakamura finite difference scheme. The genericity of the software tool is in the sense that it is a common solution to the category of time dependent laminar fluid flows expressed in one spatial coordinate. The input equations, together with other relevant parameters, are transformed into postfix code which will be farther interpreted in the computation process. The influence of the various parameters entering into the problem is shown graphically followed by a discussion of results.

The Application of Synthetic Fuzzy Assessing Method in Measurement and Control System of Plating Solution Evaporator

The synthetic fuzzy assessing method is usually applied to sensory evaluation. The method has simple and reliable virtue, and it is consistent with objective evaluation results. Using this method, system status of plating solution evaporator is evaluated, and the result is applied to compensate a fuzzy controller. Experimental results have shown the correctness and the validity of the proposed approach.

基于Ventsim的超深部多中段同时开采通风系统优化

矿井通风系统与井下各作业点相联合,对全矿井的通风安全状况具有全局性的影响,长期以来矿井通风系统优化是地下深部开采面临的重要难题。某大型地下超深部开采铜矿生产过程中存在矿体走向短、倾角大,多中段同时开采导致采区工作面分散,通风系统风路复杂的难题。基于此,利用Ventsim软件建立该矿井三维通风系统仿真模型,以矿井需风量为出发点,提出针对三、四、五采区的通风系统优化方案,模拟-300~-700 m深度内9个通风最不利中段同时开采情况,并进行通风系统网络解算。结果表明:矿井最不利通风条件下总风量为405.3 m^(3)/s,满足计算的矿井需风量395.5 m^(3)/s的要求。研究成果对矿山安全高效生产,提高矿山经济效益具有重要参考价值。

运动微分方程数值求解的一般方法分析

分析了常见物体运动微分方程的建立过程以及利用科学软件对方程数值求解的技术基础,对撒克逊碗、磁场中的弹簧摆和三摆混沌系统进行了数值求解和分析讨论,给出了解决这类问题的一般思路和方法步骤.

铁路信号机房外部冲击电流监测原理及软件分析策略

针对铁路信号机房应用场景下常见的外部冲击电流问题,从基本监测原理、软件分析策略两方面提出具体解决方案,基于该方案可实现对多频段冲击电流的综合采集以及冲击电流详情自动化分析,实现对设备管理单位的指导性建议,提升铁路信号机房运行的安全性。

A Unified Measurement Solution of Software Trustworthiness Based on Social-to-Software Framework

As trust becomes increasingly important in software domain, software trustworthiness--as a complex high- composite concept, has developed into a big challenge people have to face, especially in the current open, dynamic and ever-changing Internet environment. Furthermore, how to recognize and define trust problem from its nature and how to measure software trustworthiness correctly and effectively play a key role in improving users＇ trust in choosing software. Based on trust theory in the field of humanities and sociology, this paper proposes a measurable S2S （Social-to-Software） software trustworthiness framework, introduces a generalized indicator loss to unify three parts of trustworthiness result, and presents a whole metric solution for software trustworthiness, including the advanced J-M model based on power function and time-loss rate for ability trustworthiness measurement, the fuzzy comprehensive evaluation advanced-model considering effect of multiple short boards for basic standard trustworthiness, and the identity trustworthiness measurement method based on the code homology detecting tools. Finally, it provides a case study to verify that the solution is applicable and effective.

区域注浆扰动下渗流场−化学场演化及耦合作用

在淮北煤田普遍采用地面定向钻高压注浆技术治理煤系底板岩溶水害。注浆后渗流场补径排路径发生变化,且注浆实施中注浆高压以及浆液析水会在一定时期内改变受注目标含水层地下水渗流场和化学场的分布特征。以淮北煤田桃园煤矿为研究对象,利用Feflow软件,构建了区域注浆扰动下目标层渗流场与化学场(简称“双场”)演化模型,探讨了“双场”耦合机制,选择受环境影响较小的Cl−为模拟因子,开展了“双场”耦合作用下溶质运移影响因素分析,在此基础上构建了区域注浆扰动下溶质扩散预测模型。研究结果表明:识别验证后渗流场模型中,模拟水位与实测水位误差小于3 m的点占71.9%,模拟效果较好;识别验证后化学场模型中,Ⅱ4采区溶质运移模拟效果较好,Ⅱ1采区模拟值偏低约14.4 mg/L,误差约为实际值的6.6%,低于10%,总体模拟效果较好。渗透系数相对较大的Ⅱ4采区和Ⅱ2采区Cl−较容易运移扩散;而渗透系数较小的Ⅱ1采区岩石致密,渗透性较差,模型运行50 a期间,其基本以“滞水”状态存在。基于注浆扰动下Ⅱ4采区局部渗流场演化特征,认为溶质运移主要受渗透系数、弥散度、水力梯度、渗透流速、注浆时间、浆液相对密度等参数控制,并发现在注浆结束后18~22 a Cl−质量浓度达到峰值,随后Cl−质量浓度开始降低,约在40 a后达到区域注浆之前的平衡状态。基于多次设参运行获得数据,建立了“双场”耦合作用下溶质扩散的预测模型,误差率小于10%的数据占比达81.4%,说明所建立的溶质扩散预测模型基本可靠。研究可为区域注浆扰动下受注目标含水层水环境演化研究以及煤矿水害预测预警提供科学依据,具有重要的理论和实践意义。

(2-PUR/UPS)&R混联式颈椎外骨骼的设计及运动性能分析

针对颈椎病患者的颈部牵引康复训练,提出了一种混联式(2-PUR/UPS)&R颈椎康复机器。该机器具有3R1T共4个自由度,符合人体颈椎的活动度要求;通过对该机器的运动学性能分析,验证其是否可以应用在人体颈椎康复领域。首先,利用螺旋理论和修正的Kutzbach-Grvble公式对机构的自由度进行求解和验证;其次,通过求解机构的位置反解,得到机构的杆长,编写求解工作空间的程序,利用数值搜索法得到机构的工作空间;最后,通过Adams软件对该机构进行了仿真分析。结果显示,该机构能够达到颈椎活动所需的范围,其中,前倾后仰为-55°~35°,左旋右旋为-52°~52°,左右侧屈为-45°~45°,能够为颈椎病患者提供牵引治疗。

文物信息系统数据管理方法研究

针对当前文物信息系统在文件上传过程中存在的文件接收不全、文字乱码、传输无法随时终止等缺陷,研究了一种效率更高的文件上传解决方案。首先,该方案基于FTP协议对文件上传的可控性,保证了目录文件的完整传输,其次,通过断点续传技术解决了服务端大文件传输时的中断响应问题;最后利用ConcurrentQueue分段存储技术和文件复位技术优化了客户端接收文件的完整性和精准度。经过大量测试,所提方案能有效修复了文物信息系统中关于文件传输功能的漏洞,提高文件上传效率。

地下水溶质运移软件(GTS)设计与实现

随着全球工业的快速发展,生态环境遭到严重破坏,环境污染日益加剧。地下水污染对生态环境有着消极的影响,地下水污染研究已成为水文地质和环境保护的一个重要研究课题。地下水溶质运移软件(GTS)被设计用于精准预测地下水溶质物质的运移路径、时空分布及运移速率,从而指导地下水污染防治与制定环境保护策略。本文介绍了GTS软件的基本功能及其实现原理,包括地下水模型和运移系数模型、地下水溶质数据处理程序和模拟结果图形化显示程序。本文综述了GTS软件的设计与开发思路,介绍了GTS软件的系统架构及整体架构,探讨了GTS软件的系统设计方法。此外,本文还对GTS软件的实现进行了一些案例分析,以验证GTS软件的有效性和可靠性。

4-CPS/UPU并联机构运动学分析与仿真

提出了一种用于并联机床领域的4-CPS/UPU并联机构。基于旋量理论,建立了该并联机构的运动和约束螺旋系,该机构具有5个自由度,可实现三移两转功能;通过修正的K-G公式对其自由度进行了验证;进一步分析了并联机构的位置正逆解、工作空间;运用Adams软件对其进行了仿真分析。该机构工作空间连续,形状近似四棱台,规则对称,无空洞,且仿真得到的位移和速度曲线光滑,表明该机构具有良好的运动性能。研究结果为其在并联机床领域的参数化设计提供了一定的理论基础。

GNSS软件在地质灾害监测中的精度分析及思考

GNSS地表位移监测是地质灾害监测中的重要内容之一,GNSS解算软件的精度直接影响监测成果的可靠性。本文以南方SMOS软件作为测试软件,通过在稳定区域搭建测试环境,验证解算软件的内符合精度;研制可伸缩移动式刻度支架,通过上、下、左、右移动一定距离,验证解算软件的外符合精度。选取典型环境的地质灾害监测站点,分析卫星数据质量,通过合理配置解算参数以保证解算效果达到最优状态。

基于Phyphox验证朗伯-比尔定律和测多溶质溶液的浓度

利用红/绿激光笔、手机、水槽等简单器材,搭建了光度计模拟实验装置.基于Phyphox软件,利用手机的光敏传感器测量透射光的光强,获得溶液层的吸光度随溶液浓度和厚度的变化关系.结果表明:溶液层的吸光度与溶液浓度及厚度成正比,验证了朗伯-比尔定律.以Fe_(2)(SO_(4))3溶液和KCr(SO_(4))_(2)溶液为例,测量了含有2种溶质的混合溶液各溶质的浓度.

Hydrus-1D软件模拟污染土壤重金属溶质运移

为了研究污染物在不同性质土层中的运移规律,以某化工厂污染土壤中的重金属为研究对象,选取土壤中的Cr^(6+)、Hg^(2+)、Cd^(2+)为污染物预测因子,应用Hydrus-1D软件建立重金属溶质运移模型,模拟重金属溶质在土壤中的运移变化过程,得到其在不同时间段的下渗最大距离和在不同土层的浓度平衡时间。结果表明:所建立的模型能够模拟重金属溶质在土壤中的分布和运移的时空变化规律;当下渗时间为200、1000 d时,Cr^(6+)、Hg^(2+)、Cd^(2+)的最大下渗距离分别为1.78、2.23、2.09 m和4.55、5.70、5.54 m;在杂填土和重壤土中,Cr^(6+)、Hg^(2+)、Cd^(2+)到达平衡所需的时间分别为1025、1430、1410 d和2280、3000、3019 d。

基于Isight软件的白车身多目标优化方法

白车身(BIW)是汽车的重要组成部分,对驾乘人员的安全起到最直接的保护作用,其基本性能尤为重要,然而各性能之间往往存在冲突性,某一项性能的提升往往对其他项性能产生消极作用。为了在汽车车身设计过程中,更好地权衡某些性能,找到与设计车型目标性能更为匹配的设计参数,文章以某一小型纯电动汽车的白车身为例,通过有限元方法仿真分析其性能,再应用Isight软件采集数据并建立模型,找到多目标最优解,以供设计师选择满足设计目标且性能尽可能优异的设计参数,该设计方法对白车身参数设计具有一定的参考意义。

四阶偏微分方程的数值解法可视化软件仿真

为了实现对仿真目标的可视化绘制,提出基于四阶偏微分方程数值解法的可视化软件仿真方法。结合仿真目标参数域设计用于仿真目标属性求解的四阶偏微分方程,采用MATLAB数值解法求解偏微分方程,并设计属性精确值求解的边界条件。在MATLAB偏微分方程工具箱中,通过对应的操作指令,设计仿真目标初始曲面后,准确提取仿真目标属性的精确解,在初始曲面的基础之上绘制仿真目标的可视化图像。测试结果显示,上述方法应用后,绘制的可视化仿真图像画面光滑,可优化仿真目标可视化图像绘制效果。

支撑综合能源业务开展的移动辅助工具开发及应用

综合能源自身业务的复杂性要求相关从业人员具有很高的专业性,而实际上与综合能源客户最接近的前端人员却很难具备这个能力。针对这一问题,文章通过汇总分析不同类型用户的能效需求,抽象出生产节能、冷热站建设等典型的综合能源能效业务场景;分析不同场景的核心解决方案,形成“输入-计算-输出”的个性化定制方案。结果表明,该移动辅助工具可以极大提高前端人员的工作效率,促进综合能源项目的落地。

关于商用GPS平差软件相关问题的分析

GPS定位技术测量精度高、效率高,广泛应用于控制测量中,各种型号的GPS接收机的测量数据一般使用其随机所带的商用平差软件进行平差计算,但均与现行的《全球定位系统(GPS)测量规范》相关要求存在不一致的情况。本文结合实际测量案例,从GPS控制网平差入手,探讨分析商用GPS平差软件计算结果在数据质量检核方面与国家标准要求不一致之处,并提出合理的解决方案。