The auxiliary feedwater electric pump, which is vital in nuclear power units, demands exceptional seismic reliability. The impact of the seismic excitation direction on the seismic response of the complex auxiliary feedwater electric pump structure remains inadequately understood, thereby introducing uncertainties into seismic analysis and equipment installation procedures. To address this challenge, this study centers on a representative horizontal multi-stage centrifugal pump based on the finite element model and modal analysis. Utilizing the response spectrum method and the square root of the sum of the squares (SRSS) vibration pattern superposition principle, the research comprehensively explores the seismic response characteristics of individual pressure-bearing components and key rotor positions under seismic excitation from various angles. Findings reveal intricate variations in maximum stress and displacement responses for each pressure-bearing component under safe shutdown earthquake (SSE) level seismic excitation, corresponding to different input angles of seismic spectra. In assessing the seismic operability of the clearance between the impeller and the stator, the direction near 45° exhibits the maximum displacement response, highlighting the need for focused attention in testing and verification checks. The methodologies and conclusions presented in this paper offer valuable insights for designing, optimizing, and installing horizontal multi-stage centrifugal pumps, including auxiliary feedwater electric pumps, providing valuable guidance for future applications in the field.

颗粒饲料接触参数是获得渔业投饲装置与颗粒饲料之间相互作用的关键因素.为得到草鱼颗粒饲料离散元参数,选取漏斗法进行堆积角实际试验和仿真试验,应用MATLAB图像处理和EDEM软件自带的量角器功能提取饲料堆休止角,使用响应面优化的方法对草鱼颗粒饲料离散元参数进行标定.通过Plackett-Burman试验挑选对颗粒堆休止角有显著影响的参数,根据最陡爬坡试验快速进入显著性参数最优点的附近区域,再Box-Behnken试验建立休止角与参数之间的数学模型,最后寻优得到一组最优的显著性参数.使用最优参数进行仿真试验,对比仿真值与实测值,得到两者之间没有显著性差异(P>0.05),表明应用响应面优化标定颗粒饲料离散元仿真中所需的参数是可行的;同时,基于堆积试验得到的离散元参数可为研究自动投饲机的性能与优化提供理论基础.

基于激光制造的现代加工技术是工科学生的必修课程,由于受实验场地、实验设备、安全性等条件的限制而不能满足实验教学需求.为了构建以学生为中心、以能力培养为核心的实验教学平台,介绍了一种基于Unity3D开发的激光切割虚拟仿真实验教学系统.该系统采用图形用户界面和对话框驱动,能够模拟真实的激光切割加工过程,包括实验原理、部件认知、加工参数、激光制造过程、工艺参数对切缝宽度的影响、实验结果分析等内容,弥补了实验条件、实验成本、交互性、安全性等诸多不足,有助于提高学生的学习积极性、创新精神和实践能力.

立式V型曲面开缝网板在拖网捕捞中应用广泛,网板的水动力性能研究有助于了解网板的最佳工作冲角、网板的升力系数和阻力系数随工作冲角的数值变化.通过研究网板的最佳工作冲角能够提高网板的使用性能,提高网板的渔获效益.通过数值仿真的方法对网板的水动力性能进行研究,主要研究在5种流速下的升力系数、阻力系数、升阻比在冲角范围为10°～90°的变化及网板周围的流线型与涡流图.研究表明网板的阻力系数随着冲角的增加持续上升,而升力系数与升阻比呈先上升后下降的趋势,网板在45°时取得最大升力系数,表明临界冲角为45°,在20°时,升阻比取得最大值.网板升力系数在冲角45°之前不断上升,冲角45°之后,升力系数不断下降,冲角45°时网板背流面出现了流动分离,所以45°是网板的最佳工作冲角.

材料在扭转、弯曲组合变形条件下的力学问题是材料力学的重要教学内容,目前由于受实验场地、设备台套数不足等条件限制而不能满足教学需求.为了构建以学生为中心的虚实结合教学新模式,基于Unity 3D程序开发了一套材料组合变形虚拟仿真实验系统.该系统采用图形用户界面和对话框驱动,能够模拟真实实验的操作过程.在此基础上,提出了课堂理论教学、虚拟仿真实验、实操实验相结合的教学模式,实践表明,这种教学模式能够提高教学质量,并有助于培养学生的创新精神和实践能力.

本文基于当前课程思政建设的社会大背景,从教学内容、教学方法等方面,比较具体地阐述了《工程力学》课程思政的实施方法,为工程力学思政教学提供了一定参考.

为方便在极地开展南极磷虾的科学研究,设计并制作了南极磷虾生态模拟暂养系统.该系统由多功能可拆卸暂养箱和基于多传感器检测的生态环境模拟控制系统组成.暂养箱通过可变化的分隔结构设计为磷虾暂养提供了多变的暂养空间,极大地方便对磷虾个体、群体行为观察研究.生态环境模拟控制系统实现了暂养箱水体环境,如溶氧量、盐度、pH、温度等多参数的监测和自动控制调节.该生态模拟暂养系统已在南极科考站点试验使用.利用该系统实现了南极磷虾的暂养,并完成了南极磷虾个体、群体行为观察和生态环境参数改变磷虾生态性能变化等试验.试验结果表明该系统可满足南极磷虾在南极科考研究使用需求.

《工程流体力学》课程主要阐述流体平衡和运动的基本规律及其有关的基本概念、基本理论、基本计算方法和基本实验技能.要求学生不仅要掌握流体力学相关知识和理论,还要学习流体力学中蕴含的唯物主义哲学思想及科学精神等思想政治教育相关内容.文章以上海海洋大学《工程流体力学》课程为例,探讨《工程流体力学》课程中所蕴含的思政教育内容以及德育实施情况.

以飞行炮弹的六自由度刚体动力学建模与仿真为例,介绍了一种将MATLAB/Simulink可视化仿真试验引入理论力学课堂的教学方法.该方法倡导以理解理论知识为基础,以直观的数值模拟为手段,注重提高学生的学习兴趣,有助于培养学生的力学建模和分析解决实际工程问题的能力.

为了优化某种轴流式浪流发电机导流罩的加速性能,研究其主要的结构参数对加速性能的影响.采用数值模拟与实验设计相结合的方法,选取扩口段长度、中间段长度和开口张角为主要因素.选取L9(34)正交表,得到9组方案,在FLUENT中建立出不同结构参数的下的导流罩数值模型,以导流罩的增速性能为评价指标,对直线型导流罩进行正交试验.通过极差分析法,探索主要结构参数对其加速性能影响规律,得出对其加速性能影响的主次顺序,最终得出当扩口段长为1000 mm、中间段长度为800 mm、开口张角为15°时为最优的参数组合.为轴流式浪流发电机的导流罩设计提供参考依据.

本文针对当前普通高校理论力学讲授学时大量减少的问题,根据多年的教学实践,从教材、教学内容、教学方法和教学手段等方面,归纳总结了普通高校理论力学少学时教学的几点切实可行的教改措施,为理论力学的教学提供建设性意见和建议.

In order to study the mechanical properties of tuna longline hooks,and to verify the accuracy of the finite element analysis method,this study conducted tensile test and ANSYS simulation on the ring hook (Type:3.4-4.5).The results of tensile test and ANSYS simulation were compared and tested by ANOVA.The results showed that:(1) there were no significant differences of the mechanical characteristics e.g.displacement or strain,measured by two methods (P ＞ 0.05).The maximum strain area was around the back bent and rear side.The maximum total displacement area was around the front bent and front axle.The maximum displacement in Ⅹ direction was around the bottom and rear side.The maximum displacement in Y direction was around the back bend and back axle;(2) when the tension was 500,800,and 1200N,the ring hook's strain was 0.002 76,0.008 14,and 0.069 94;the displacement in Ⅹ direction was 1.8,3.5,and 7.2 mm;the displacement in Y direction was-2.4,-4.6,and-8.7 mm;the total displacement was 2.8,5.4,and 10.6 mm,respectively;(3) there was a significant linear relationship between the results of tensile test and those of the ANSYS simulation.The displacement in total,X,Y direction,and strain of tensile test were 1.018 9,1.027 2,1.019 5,and 1.088 3 times the ANSYS simulation.This study suggested that the ANSYS finite element could be used to analyze tuna longline hooks' mechanical property.

A recombinant peptide Pro-Pro-[Arg11]hPTH(1-34)-Pro-Pro, was designed, biosynthesized, and purified in our lab (generated by substituting Arg for Leu at position 11 and adding -Pro-Pro to the carboxyl terminus of hPTH(1-34)-peptide), and reported to be capable of enhancing serum calcium level in chicken. In this investigation, we studied its impact on the structure, component, and biomechanical properties of rat bones. The pharmacological effect of Pro-Pro-[Arg11]hPTH(1-34)-Pro-Pro was investigated to evaluate its therapeutic potential for the treatment of osteoporosis, one of the most prevalent and rapidly spreading diseases in the world. 3-month-old normal female rats were sham-ovariectomized or ovariectomized, then fed for 14 weeks. Small doses of Pro-Pro-[Arg11]hPTH(1-34)-Pro-Pro were given to the rats afterward (daily subcutaneous injection of 0.4-0.9nmol/100g body weight for 16 weeks). Values of various parameters, including the body weight, the bone mass, the bone geometry, the bone biomechanics, the bone histology, the bone histomorphology, and the serum biochemistry, were collected before or after animal sacrifice. Daily subcutaneous injection of Pro-Pro-[Arg11]hPTH(1-34)-Pro-Pro induced 37.0-42.4% increase in vertebral BMD, 28.5-47.9% increase in femoral BMD, 30.7-43.7% decrease in marrow cavity or increase in trabecular bone area. The peptide also increased calcium, phosphorus, and collagen in bone by 52.1-59.7%, 24.5-34.7%, and 26.3-28.0%, respectively. In terms of mechanic properties, peptide administration elevated bone rigidity by 55.7-84.5%, decreased the deflection by 14.8-26.7%, and improved modulus of elasticity by 28.1-76.4%. These data suggest Pro-Pro-[Arg11]hPTH(1-34)-Pro-Pro has a positive effect on bone mass accumulation and microstructure improvement, fortifies bone strength, and possesses anti-aging capability, which may merit further investigation.

Fluid simulation software FLUENT was used to study the flow distribution of vertical SLAT type otter board, when the SLAT angle (0) ranging from 28 to 40 degree, and analyzed the relationship between SLAT angle and lift coefficient, drag coefficient, lift-to-drag ratio. Simulated the flow distribution in different attack angles (alpha) when the velocity at 1.54 m/s, analyzed the relationship between attack angles and lift coefficient, drag coefficient, lift-to-drag ratio. Also simulated the dynamics parameters when the velocity changing from 0.51 to 2.57 m/s, analyzed the relationship between Reynolds and lift coefficient, drag coefficient, lift-to-drag ratio. Aimed at provided theoretical help for the design and improvement of the otter board.

为了在我国金枪鱼延绳钓渔业中推广应用圆型钓钩,必须掌握圆型钓钩、环型钓钩受力时的位移和应变等力学性能.实验对环型钓钩3.4～4.5和圆型钓钩14/0～4.5采用万能实验机进行拉伸实验,利用数字图像相关测试系统对实验过程中钓钩的位移、应变等进行动态测量.结果显示:(1)当拉力为0～500 N、500～800 N时,圆型钩14/0～4.5最大应变分别为0.012、0.018,环型钩3.4～4.5最大应变分别为0.010、0.025;(2)当拉力为0～500 N、500～800 N时,圆型钩14/0～4.5最大位移分别为5.16 mm、8.50 mm,环型钩3.4～4.5最大位移分别为4.36 mm、6.01 mm.环型钓钧3.4～4.5为4.36 mm.对环型钓钩3.4～4.5和圆型钓钩14/0～4.5应变、位移进行卡方检验,发现环型钓钩3.4～4.5、圆型钓钩14/0～4.5力学性能无显著性差异.研究建议今后在金枪鱼延绳钓渔业中推广应用圆型钓钩.

Automatic cotton picker was widely used in contemporary cotton production operations, moreover, the farmers prefer to small cotton picker, and picking mechanism is the most important parts of cotton picker, therefore, the research on the movement of picking mechanism is very important. This paper introduced a new kind of the opposite-two-rows type automatic cotton picker, analyzed its operating principle, and made a theoretical derivation of the equations of motion of the picking mechanism, the obtained results can provide theoretical guidance for the design of picking mechanism of cotton picker.

基于教师教学评价和学生学习效果评价两层面,分析了高校教学质量评价方案以及指标因素,给出了评价包含的指标体系与分类,为高校教学质量评价的改革与完善、评价指标的构建提供支持与参考.

The course of 《Logistics Mechanical Course Design》 is an important link of the course of《Logistics Machine Design Foundation 》.it playing the role of a bridge in transition from theory to practice and basic course to specialized course. and it can develop the students' comprehensive design ability extremely. However, there are many problems during teaching process. In this paper, the characteristics and problems of the course of 《 Logistics Mechanical Course Design 》 during teaching are analyzed. in order to improve the students' learning interest, learning initiative and teaching quality, the improve methods such as change the single method of topic selection, reduce students' duplicate work,improve object designing, reform the academic evaluation system and increase the process of prototype fabrication, are developed.

本文通过对《工程材料及机械制造基础》课程性质和特点的分析，提出了课程改革的思路和做法。重视教学内容的优化，改变传统的教学方法，灵活多样地利用多种教学手段，新增设计性实验和进行考核方式的改革。通过上述的改革和创新，提高了教学质量，激发了学生的学习兴趣，增强了学生的学习主动性，取得了良好的教学效果。

普通院校二本学生对力学课程有畏难情绪，尤其是对理论力学课程普遍感觉难学。究其原因，教师对力学课程学习的课下练习环节重视、研究不够，学生课下练习质量不高是主要问题。针对这些问题摸索出一些具有可操作性的措施。