Capacity-based performance measurements for loading equipment in open pit mines

The purpose of this study is to develop an integrated framework for capacity analysis to address the influence of systematic hazardous factors on the haulage fleet nominal capacity.The proposed model was made to capture unexpected risks for mining equipment based upon data-driven method considering different scenarios.Probabilistic risk assessment(PRA)was employed to quantify the loss of production capacity by focusing on severity of failure incidents and maintainability measurements.Discrete-event simulation was configured to characterize the nominal capacity for mining operation.Accordingly,the system capacity was analyzed through the comparison of nominal and actual capacity.A case study was completed to validate the research methodology.The past operation and maintenance field data were collected for shovel operation.The discrete-event simulation was developed to estimate the rate of shovel nominal capacity.Then,the effects of undesirable scenarios were assessed by developing the PRA approach.The research results provide significant insights into how to enhance the production capacity in mines.The analyst gets a well judgment for the crucial elements dealing with high risk levels.A holistic maintenance plan can be developed to mitigate and control the losses.

Coordinating and Evaluating of Multiple Key Performance Indicators for Manufacturing Equipment: Case Study of Distillation Column

Manufacturing equipment takes the task of operation and directly effects on the manufacturing process. One single Key Performance Indicator （KPI） is mainly employed to evaluate equipment in most studies, neither integrating the KPIs into a completed evaluation system nor considering the impact and conflict among KPIs. In this paper, a KPI evaluation architecture is presented to define and analyze KPIs, and then a common structure for KPI to obtain the KPI set of manufacturing equipment is introduced. An available multi-KPl coordination model is proposed to discern and balance the relationship among multi-KPl. Finally, a case study is introduced to illustrate the applicability of the coordination model by using multi-objective optimization strategy and an efficient solution is obtained.

Shaking table test study on performance and functionality of a typical telecommunication room after earthquakes

Large numbers of basic transceiver stations,where the telecommunication room is one of the main components,comprise an important part of the telecommunication system.After earthquakes,considerable economic loss from telecommunication systems is often associated with seismic damage and functional loss of the telecommunication room.However,research related to this has been limited.In this study,shaking table tests were conducted for a full-scale typical telecommunication room,including a light-steel house and the necessary communication and power supply equipment.The tests not only focused on the seismic damage to all the structures but also considered the functions of the communication and power supply of the equipment.The interactions between these facilities and their effects on communication function were also investigated.Compared with the damage to structures,the interruption of the power supply due to earthquakes is a weak link.Finally,the damage indexes,together with their threshold values of different damage states for the communication and power supply equipment,were derived from the test results.The results of this research can contribute to the literature gaps regarding seismic performance studies of telecommunication rooms,and can serve as a valuable reference for future research on its seismic fragility and economic losses evaluation.

Study on a conical bearing for acceleration-sensitive equipment

Seismic isolation effectively reduces seismic demands on building structures by isolating the superstructure from ground vibrations during earthquakes.However,isolation strategies give less attention to acceleration-sensitive systems or equipment.Meanwhile,as the isolation layer’s displacement grows,the stiffness and frequency of traditional rolling and sliding isolation bearings increases,potentially causing self-centering and resonance concerns.As a result,a new conical pendulum bearing has been selected for acceleration-sensitive equipment to increase self-centering capacity,and additional viscous dampers are incorporated to enhance system damping.Moreover,the theoretical formula for conical pendulum bearings is supplied to analyze the device’s dynamic parameters,and shake table experiments are used to determine the proposed device’s isolation efficiency under various conditions.According to the test results,the newly proposed devices have remarkable isolation performance in terms of minimizing both acceleration and displacement responses.Finally,a numerical model of the isolation system is provided for further research,and the accuracy is demonstrated by the aforementioned experiments.

Off-Design Performance Analysis of Axial Flow Fan in Helicopter

A theoretical calculation method of off-design performance is developed for an axial flow fan of oil cooling system in helicopter,including calculation of aerodynamic parameters and performance parameters.When calculating inlet shock loss,the shock loss coefficient is obtained by comparing results of theoretical calculation,experimental and numerical calculation.The theoretical results and numerical results show that all air velocity components increase from hub to shroud in main flow area at rated condition.Tip leakage vortex moves downstream as flow rate increases.When flow rate decreases,Re decreases,and boundary layer thickness from hub to shroud area all increases gradually.Tip leakage vortex moves upstream,and secondary loss increases.Low speed area in the passage is widened along with high speed area moving to hub area,influenced by boundary layer separation.Consequently wake area and jet area at fan outlet are both larger than rated condition.Therefore optimization design for off-design performance of the fan is required on aerodynamic parameters influencing fan loss.A reliable method is supplied for estimating altitude performance of lubricating system in helicopter.

Energy and Exergy Analysis, and Thermoeconomic Performance of a BCHP System

Building cooling, heating and power (BCHP) systems should play an important role in achieving the goals of energy efficient use and environment protection in China. It will make big sense when this type of system shows a good performance energetically and economically. An on-site BCHP system being the first in the country was installed and put to use five years ago. As the first step to evaluate the project, computations were made based on thermodynamic and thermoeconomic theories to evaluate the system on full load and off-design conditions in summer. Discussion and analyses are made mainly in terms of exergetic efficiency and costs of unit amount of useful exergy produced in this paper.

Test Apparatus for Performance Evaluation of Compressed Air End-Use Applications

Compressed air is an integral utility part of industrial utility systems. Any improvement in compressed air system will lead to reduction in utility cost. The effectiveness of utilization side of compressed air is usually dependent upon operator’s discretion. There are no performance testing methods available for testing existing end use equipments. A test apparatus for estimation of compressed air flow based on measurement of pressure reduction in a fixed volume cylinder in a given time is developed. The test apparatus is easy to build and simple to operate in an industrial environment. This can be used for measuring performance of any pneumatic end-use equipment and for benchmarking the performance. The test apparatus was used in a foundry for quantifying the performance of the old and new blow guns.

Supercritical CO_(2) Cycles for Nuclear-Powered Marine Propulsion:Preliminary Conceptual Design and Off-Design Performance Assessment

Using the efficient,space-saving,and flexible supercritical carbon dioxide(sCO_(2)) Brayton cycle is a promising approach for improving the performance of nuclear-powered ships.The purpose of this paper is to design and compare sCO_(2) cycle power systems suitable for nuclear-powered ships.Considering the characteristics of nuclear-powered ships,this paper uses different indicators to comprehensively evaluate the efficiency,cost,volume,and partial load performance of several nuclear-powered sCO_(2) cycles.Four load-following strategies are also designed and compared.The results show that the partial cooling cycle is most suitable for nuclear-powered ships because it offers both high thermal efficiency and low volume and cost,and can maintain relatively high thermal efficiency at partial loads.Additionally,the new load-following strategy that adjusts the turbine speed can keep the compressor away from the surge line,making the cycle more flexible and efficient compared to traditional inventory and turbine bypass strategies.

基于DEMATEL&CIM的化工企业特种设备双重预防机制运行绩效灰色评估

针对化工企业特种设备双重预防机制特点和绩效评价影响因素的复杂性和指标的不确定性,提出基于DEMATEL&Grey-CIM的方法,用于双重预防机制运行绩效评价。建立了特种设备双重预防机制运行绩效评价的结构模型,采用DEMATEL法确定指标权重,运用Grey-CIM方法进行评价。该方法既能给出运行绩效等级分布概率,还可对双重预防机制运行的配置和调整给予指导。

分立式开关电源系统抗震性能的振动台试验研究

开关电源是通信机楼和通信基站中最重要的设备之一,相当于机楼和基站内供电系统的“心脏”,若在地震作用下发生功能失效将导致通信机楼和基站完全停止工作。开关电源的抗震性能研究是通信系统抗震韧性评估研究的基础。本文以通信机楼内常用的分立式开关电源系统为研究对象,通过振动台试验研究其在地震下的特征损伤模式、损伤发展过程以及其供电功能在地震作用下的变化等。试验过程中为了模拟开关电源在通信机楼中的实际使用状态,为开关电源连接了380 V电压输入和一台模拟负载,组成了一个完整的用电系统。试验中台面激励采用了1条人工地震动、1条天然地震动和1条正弦拍波,逐步增大台面PGA直至振动台位移超限停止试验。从试验结果看:当PGA达到1.0 g时电源柜开始损伤,表现为柜门与主框架磨损掉漆,PGA在1.2~1.5 g时,电源柜顶部连接松动,面板连接螺丝松动,螺栓孔发生冲切破坏,PGA达到2.0 g时,试验结束,电源柜的主体未发生严重破坏,交流柜与直流柜前门轴变形;另外即使在较大PGA下,正弦拍波也无法对电源柜激起较大位移而造成破坏。试验过程中电气信号始终稳定,该开关电源柜抗震性能良好。

绩效目标分层管理模式在医疗设备采购过程管理中的价值研究

目的:构建绩效目标分层管理模型,探讨其在医疗设备采购过程管理中的应用价值。方法:从医疗设备采购申报层、过程层、使用层和处置层筛选采购绩效评价指标,采用熵权法和数据包络分析(DEA)法制定综合评价模型,形成人员、制度、数据和设备层面的过程管理方案。选取2019—2022年北京佑安医院采购的717台医疗设备,根据绩效目标评价方法不同分别采用传统管理模式(348台)和分层管理模式(369台)管理,对比不同管理模式下医疗设备采购的绩效目标完成度、采购过程管理质量和临床配置管理满意度。结果:采用分层管理模式的369台设备包括手术室设备、实验室设备、住院治疗设备、消毒供应设备及其他医疗设备,其采购的绩效目标完成度分别为(96.10±3.46)%、(96.76±2.65)%、(95.59±2.52)%、(96.06±2.34)%和(96.88±1.75)%,均高于传统管理模式,差异有统计学意义(t=2.663、2.801、2.858、4.111、3.548,P<0.05);采用分层管理模式的医疗设备采购申报层、过程层、使用层和处置层的综合评价DEA有效率分别为96.7%、98.6%、94.6%和99.7%,均高于传统管理模式,差异有统计学意义(χ^(2)=10.983、9.327、7.270、12.309,P<0.05);临床科室使用管理人员对采用分层管理模式的设备采购和使用平均满意度分别为(95.82±2.83)%和(97.25±1.96)%,均高于传统管理模式,差异有统计学意义(t=5.575、5.248,P<0.05)。结论:分层管理模式能够有效落实医疗设备采购绩效目标,提高医疗设备采购过程管理质量,提升采购后配置临床科室使用和管理人员满意度,保障设备运行质量。

载人航天舱内设备单机插拔装置设计及验证

为提高载人航天舱内电子设备的在轨维修性和可操作性,综合考虑轻量化便携、人因工程学和结构动力学性能等因素,采用分体式可调节设计技术设计一种新型的舱内电子设备单机在轨安装与脱离的插拔装置。采用多刚体动力学仿真分析对装置结构动力学性能进行验证,采用有限元仿真分析对曲柄抗扭性能进行验证。最后,通过实物操作验证装置在真实工作状态下的可行性和有效性。

医疗设备管理系统的构建与实践

目的为助力医院高质量发展,构建一套高效能的医疗装备管理系统。方法使用波特价值链模型梳理医疗设备全生命周期管理的模块需求,运用B/S架构结合射频识别技术,采用JAVA开发工具和Oracle数据库,构建集“购+管+养+控”于一体的医疗设备全生命周期管理系统,实现设备的申请购置、档案管理、维护保养、质量控制等功能,并对其应用效果进行评价。结果系统应用后,设备申请购置的工作效率提升显著,用时缩短了75%;多项设备管理工作平均用时显著缩短,差异有统计学意义(P<0.05);生命支持类设备维修率同比大幅下降;临床对软件的满意度较高,整体满意度在80%以上。结论医疗设备全生命周期管理系统的构建与实践提升了医疗设备管理效率,降低了运维成本,实现了医疗设备规范化、精细化和智能化管理,助力了医院的高质量发展。

体育领域用超纤革制备及其性能研究

为改善体育领域用超纤革综合应用性能,提高超纤革手感与质感,本文以高收缩纤维切片与聚酰胺切片混合制备了体育领域用高收缩聚酯纤维超纤革基布与成革,并与聚酯纤维超纤革基布与成革进行了性能对比分析。结果发现,体育领域用高收缩聚酯纤维超纤革力学性能与卫生性能存在显著性差异;相比聚酯纤维超纤革基布,高收缩聚酯纤维超纤革基布纤维间孔径较小;相较于聚酯纤维超纤革,高收缩聚酯纤维超纤革纵向与横向断裂强力偏低,而纵向与横向断裂伸长率较大,柔软度更大,透气率和透湿率更高,吸水量更大,表明其力学性能相对较优,且卫生性能整体更佳。

运动康复器械用高性能胶粘剂的粘接性能研究

为了提高运动康复器械用胶粘剂的粘接性能,以线性T1胶粘剂和非线性Tc胶粘剂为原料对运动康复器械用钢管和碳纤维增强基复合材料(CFRP)板进行了粘接,考察了胶粘剂厚度对粘接性能和破坏模式的影响,并采用计算模拟的方法对粘接强度进行了预测。结果表明,相较于线性T1胶粘剂,非线性Tc胶粘剂的拉伸强度和弹性模量相对较小,而最大应变相对较大。无论是线性T1胶粘剂还是非线性Tc胶粘剂试样,界面极限承载力试验值与界面极限承载力计算值都较为相近;线性方程斜率为0.93,相关性系数R2=0.86。可以采用胶粘剂试样的断裂能公式对极限承载力进行预测。

民用建筑电线电缆阻燃耐火性能应用研究

通过分析比对不同电线电缆阻燃耐火性能分类及试验标准,提出设计标准中阻燃类别选择存在的问题及建议。建筑物发生火灾的严重程度与建筑规模功能用途密切相关,不同建筑物的消防用电设备所需连续供电的时间也不同,消防设备配电及控制线路应满足建筑火灾延续时间内能连续供电的要求,电线电缆耐火性能的选择应与之相适应。

Design Optimization and Operating Performance of S-CO_(2) Brayton Cycle under Fluctuating Ambient Temperature and Diverse Power Demand Scenarios

The supercritical CO_(2)(S-CO_(2)) Brayton cycle is expected to replace steam cycle in the application of solar power tower system due to the attractive potential to improve efficiency and reduce costs.Since the concentrated solar power plant with thermal energy storage is usually located in drought area and used to provide a dispatchable power output,the S-CO_(2) Brayton cycle has to operate under fluctuating ambient temperature and diverse power demand scenarios.In addition,the cycle design condition will directly affect the off-design performance.In this work,the combined effects of design condition,and distributions of ambient temperature and power demand on the cycle operating performance are analyzed,and the off-design performance maps are proposed for the first time.A cycle design method with feedback mechanism of operating performance under varied ambient temperature and power demand is introduced innovatively.Results show that the low design value of compressor inlet temperature is not conductive to efficient operation under low loads and sufficient output under high ambient temperatures.The average yearly efficiency is most affected by the average power demand,while the load cover factor is significantly influenced by the average ambient temperature.With multi-objective optimization,the optimal solution of designed compressor inlet temperature is close to the minimum value of35℃ in Delingha with low ambient temperature,while reaches 44.15℃ in Daggett under the scenario of high ambient temperature,low average power demand,long duration and large value of peak load during the peak temperature period.If the cycle designed with compressor inlet temperature of 35℃ instead of 44.15℃ in Daggett under light industry power demand,the reduction of load cover factor will reach 0.027,but the average yearly efficiency can barely be improved.

面向设备性能退化监测的分步参数估计策略

为通过预防性定期维护提升化工装置的精细化管理水平,探讨了关键设备的在线性能监测原理,针对设备性能参数可估计性差的问题,提出了一种基于机理模型分析设备性能退变的分步参数估计策略,根据灵敏度分析确定参数处理规则。首先以工业装置的严格机理模型为基础给出在线的粗粒度模型候选项,以历史数据拟合误差最小为目标完成初步参数估计,给出最优模型和各参数初值。然后基于灵敏度分析矩阵特征给模型参数排序,以表征性能退变的时变参数为界,前后不同顺位的定常参数采用不同策略依次处理。最后以滑动时间窗方式估计时变参数,实现设备性能监测。以反应釜夹套换热器的传热性能监测为例,按照分步策略获得设备性能参数的退变,剥离操作变量的影响,结果与工厂操作周期符合。表示该策略可以用于设备性能监测。

双转子连续混炼设备的进展

双转子连续混炼机由于具有稳定、高效和节能的特点,在聚合物材料加工领域得到了广泛的应用。首先综述了双转子连续混炼机的国内外研发历程,梳理了双转子连续混炼机系统结构设计、转子结构优化和加工机理等的研究进展,并系统地分析了转子的楔入角、转子的螺棱数和转子的相位角等重要转子结构参数对聚合物材料结构与性能的影响。另外,总结了双转子连续混炼机在高填充母料、超高分子量聚乙烯(UHMWPE)加工和回收橡胶等领域的应用进展。最后,概述了双转子连续混炼设备的发展趋势,需要深入研究其加工机理,并且,不断朝着大型化、专业化、绿色化和智能化方向发展。

输液设备用一次性使用防回流阀的阻断性能测试方法探究

对比了YY 0585.4—2009和ISO 8536-12:20212个标准中对输液设备用一次性使用防回流阀的阻断性能测试方法,分析了根据YY 0585.4—2009进行防回流阀阻断性能测试时的影响因素和可能存在的操作误区,指出了ISO 8536-12:2021中防回流阀阻断性能的测试方法更加完善合理、科学有效,为标准修订及检测人员的实际操作提供了借鉴和指引。