Automatic Control of Automobile Transmission Performance Test Stand

To realize automatic control of automobile transmission performance test stand Methods The automatic control technique of the lubricant temperature,the program- controll- edautomaticshifting of the transmission,the continuous adjusting of revolution speed and load, data-acquisition and data real-time processing were adopted.Results The lubricant temperature was controlled at the set temperature ±2℃.The automatic shifting of the trans- mission is simple,reliable and accurate.The automatic adjusting of load and rotation speed is rapidandaccurate,the torque divergence is ±1N·m,the rotation speed divergence is ±5r/min Conclusion The four kinds of techniques are applied into the automobile transmission perfor- mance test stand successfully. mancetest stand successfully.

Tracking performance of large margin classifier in automatic modulation classification with a software radio environment

Automatic modulation classification is the process of identification of the modulation type of a signal in a general environment. This paper proposes a new method to evaluate the tracking performance of large margin classifier against signal-tonoise ratio （SNR）, and classifies all forms of primary user＇s signals in a cognitive radio environment. For achieving this objective, two structures of a large margin are developed in additive white Gaussian noise （AWGN） channels with priori unknown SNR. A combination of higher order statistics and instantaneous characteristics is selected as effective features. Simulation results show that the classification rates of the proposed structures are well robust against environmental SNR changes.

Performance Analysis of Automated Control System for Condenser Water Treatment Unit

The air conditioning system in the Umm Al-Qura University (Albdiya Campus) was conceived to be a district cooling by a remote chilled water plant. Recently, there are two chilled water plants in the university installed strategically to provide chilled water to all the academic and administrative buildings of the university through distribution network with total capacity approximately of 12,000 tons of refrigeration. The plants were built based on cooling towers with open water cycle as heat rejection system. Water treatment chemicals has been used to protect the cooling systems from corrosion, scaling and microbiological fouling accompanied with dissolved and suspended water impurities. Different methods are being used to determine and control the treatment chemical concentrations and system performance indicators. Traditional chemical controller has drawback of indirect measurements and set points. The purpose of this paper is to present a solution to overcome the problems of traditional and conventional chemical treatment and control sys-tems. Central cooling plant number (1) assigned to perform experimental setup using new chemical treatment technology. Advanced automatic chemical treatment controller installed on condensers (1, 2 and 3), and certain key performance indicators were selected and monitored such as chemical and water consumption, power, energy saving, and maintaining system integrity and efficiency. Satisfactory results were obtained in terms of performance and cost of operation.

Effective Methods and Performance Analysis on Data Transmission Security with Blind Source Separation in Space-Based AIS

In space-based Automatic Identification Systems(AIS), due to high satellite orbits, several Ad Hoc cells within the observation range of the satellite are vulnerable to interference by an external signal.To increase efficiency in target detection and improve system security, a blind source separation method is adopted for processing the conflicting signals received by satellites. Compared to traditional methods, we formulate the separation problem as a clustering problem. Since our algorithm is affected by the sparseness of source signals, to get satisfactory results, our algorithm assumes that the distance between two arbitrary mixed-signal vectors is less than the doubled sum of variances of distribution of the corresponding mixtures. Signal sparsity is overcome by computing the Short-Time Fourier Transform, and the mixed source signals are separated using the improved PSO clustering. We evaluated the performance and the robustness of the proposed network architecture by several simulations. The experimental results demonstrate the effectiveness of the proposed method in not only improving satellite signal receiving ability but also in enhancing space-based AIS security.

Automatic Generation Control of Multigeneration Power System

Load frequency Control (LFC) is used for many years as part of Automatic Generation Control (AGC) in power system around the world. In a mixed power system, it is usual to find an area regulated by hydro generation interconnected to another area regulated by thermal generation or in combination of both. In the following study, performance of AGC for Thermal, Hydro and Thermal turbine based power system is examined, including how frequency bias setting influences AGC response and inadvertent interchange. Control performance analysis of three area interconnected systems is simulated and studied through Matlab Simulink software. Integral square error and Integral time absolute error has been used as performance criterion. It is shown that integral time absolute error (ITAE) as performance index leads to faster optimization of controller gain.

Hydraulic and thermal analysis of automatic transmission fluid in the presence of nano-particles and twisted tape:An experimental and numerical study

In the present study,hydraulic and thermal behavior of an automatic transmission nano-fluid(ATNF) inside a tube with a twisted tape has been investigated.The heat transfer improvement and pressure drop of transmission oil for each of case of using twisted tape and nano-particles were also examined separately and compared with each other.The Cu O nano-particles were used to prepare the ATNF.The effects of different Reynolds numbers and different mass fractions of nano-particle were investigated.The results showed that applying nano-particles and twisted tape simultaneously increases both the pressure drop and Nusselt number,on average by about 53% and 76%,respectively.By using a parameter,namely thermal performance index η,the effect of increasing heat transfer and pressure drop was studied simultaneously.The heat transfer improvement predominates the pressure drop increment in all cases.It was observed that the highest thermal performance of 1.9 was obtained at Re=634 and Φ=2%.Furthermore,regarding the increment of the Nu number,it was shown that the use of twisted tapes individually could increase the average Nu number by 41%,while the max increment arising from individual use of 2% nano-particles is 13%,so using twisted tape is a more effective-technique for this case study.

TCP TRAFFIC PERFORMANCE IMPROVING IN LTE-A NETWORKS

This paper presents a novel way to improve Transmission Control Protocol (TCP) performance of the users at the edge areas of the macro cells in Long Term Evolution Advanced (LTE-A) systems. Previous works on improving wireless TCP performance are reviewed and current considerations on TCP in LTE-A are explained. However, those solutions are neither too complex nor limited to some presuppositions which are too restricting for the deployment of LTE-A networks. In this paper a substituted TCP acknowledgement transmission scheme based on Automatic Repeat reQuest (ARQ) information in layer 2 is proposed. The simulation result shows that the proposed method can reduce the delay and improve the throughput of the edging users of the cell, as well as reducing radio resources in LTE-A macro cells.

Hybrid Loader Automatic Shift Strategy Based on Neural Network

Hybrid loader 's comprehensive performance mainly depends on the performance of hydraulic torque converter during its driving and working. Hybrid loader and hydraulic torque converter are taken for the research objects. The primary characteristic curve of hydraulic torque converter and the traction curve of hybrid loader are acquired by analyzing the characteristic parameters of hydraulic torque converter, the characteristic parameters of engine, the characteristic parameters of battery pack and geometric parameters of hybrid loader. The gear shift curves based on the best energy saving performance and the best power performance are acquired respectively with the opening of throttle,the speed of pump wheel and the speed of turbine as parameters. Then the two curves are combined to get the comprehensive gear shift curve. Radical basis function( RBF) neural network is applied to building the gear shift strategy to keep hybrid loader with the best power performance and energy saving performance. The experimental bench is set up for experimental verification. It proves that both of the power performance and energy saving performance of hybrid loader are improved effectively by using the automatic shift strategy.

不同核酸提取方法对HBV-DNA检测性能验证情况分析

目的评估2种乙型肝炎病毒(HBV)-DNA提取方法及2家检测试剂的性能,有助于选择优化提取试剂和检测试剂。方法2023年4月采用达安全自动核酸提取仪提取法(磁珠法)和手工提取法(一步法),并用达安和圣湘2种HBV-DNA试剂检测,对其进行精密度、正确度、线性范围、检出限及抗干扰能力等性能进行验证和评价。结果达安全自动核酸提取仪提取达安试剂检测、手工提取达安试剂检测和手工提取圣湘试剂检测在精密度、正确度、线性范围、检出限方面验证结果均达标;达安全自动核酸提取仪提取圣湘试剂检测在低值检测中变异系数大于5%,最低检测限验证不合格;抗干扰能力方面,全自动核酸提取仪提取的2.0 g/dL血红蛋白浓度的样本用达安和圣湘试剂检测结果均不受影响。手工提取甘油三酯浓度达3000 mg/dL的样本用达安和圣湘试剂检测的结果均不受影响。结论不同厂家的提取和检测试剂避免混用,达安和圣湘试剂对HBV-DNA定量检测的结果均符合要求。

全自动固相萃取—高效液相色谱法测定现制饮料中7种合成着色剂

目的:建立一种全自动固相萃取—高效液相色谱双波长法测定现制饮料中7种合成着色剂的方法。方法:样品经纯水提取2次,离心后,合并上清液,调节pH至3~4。利用全自动固相萃取装置活化Poly-sery色素专用固相萃取小柱,并上样、淋洗、洗脱。洗脱液氮吹浓缩至200μL,用50%流动相A+50%流动相B混合液定容至1.0 mL。色谱柱采用C 18柱,流动相为20 mmol/L乙酸铵—甲醇,梯度洗脱,流速1.0 mL/min,进样量10μL,检测波长254,628 nm。结果:各物质在0.5~50.0μg/mL范围内相关系数均大于0.9999,方法检出限为0.023~0.179 mg/kg,定量限为0.078~0.598 mg/kg,加标回收率为92.4%~96.8%,相对标准偏差(RSD)为1.2%~4.2%。结论:该方法试剂使用量小,操作步骤简便,自动化程度高,回收率高,重复性好,适合于批量样品测定。

自动QuEChERS结合UPLC-MS/MS测定莲雾中苯并咪唑类农药残留

为了建立自动QuEChERS结合高效液相色谱-串联质谱法测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药残留量的检测方法。将莲雾样品采用混合试剂(5.5 g硫酸镁+1.5 g氯化钠+1.0 g柠檬酸钠+0.5 g柠檬酸二钠)进行净化,经QuEChERS自动样品制备系统进行制备后,应用超高效液相色谱-三重四级杆串联质谱法进行分析。结果表明,4种农药在1.00~10.00 ng/mL质量浓度范围内线性关系良好,决定系数(R2)均大于0.99;0.1、1.0、5.0 mg/kg 3个添加水平下,在莲雾基质中添加回收率为84%~105%,相对标准偏差为0.8%~9.5%(n=3),方法检出限和定量限分别为0.1~0.5μg/kg和0.5~10.0μg/kg。综上,该方法简便省时,净化效果好,灵敏度及准确度高,可用于同时测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药的残留量。

迈瑞CX-9000全自动凝血分析仪性能评估

目的:对迈瑞CX-9000全自动凝血分析仪的性能进行验证评估。方法:参照行业标准和国家标准,通过凝血酶原时间(prothrombin time,PT)、活化部分凝血活酶时间(activated partial thromboplastin time,APTT)、纤维蛋白原(fibrinogen,FIB)、凝血酶时间(thrombin time,TT)、D-二聚体5个凝血常规检查项目对迈瑞CX-9000全自动凝血分析仪进行性能验证,评估该仪器的精密度、准确度、线性范围、携带污染率及参考区间能否满足临床需求。结果:5个凝血常规检查项目的批内精密度变异系数(coefficient of variation,CV)均<3%,日间精密度CV均<5%,准确度相对偏差在±10%以内。FIB的线性回归方程斜率k为1.0060,相关系数r为0.9993,D-二聚体的线性回归方程k为1.0132,r为0.9975,线性良好。样本浓度携带污染率CR1为4.6%,项目携带污染率CR2均<2%,参考区间R值均为100%,均符合行业标准要求,验证通过。结论:迈瑞CX-9000全自动凝血分析仪是一款精密度好、准确度高、线性范围宽、携带污染率低的检测系统,能够满足临床需求。

安图A2000全自动化学发光分析仪检测IGFBP3的性能验证及与IGF-1相关性研究

目的:对安图A2000全自动化学发光仪检测血清胰岛素样生长因子结合蛋白3(IGFBP3)的性能进行评价,并探讨其在矮小症、性早熟及垂体性病变中与IGF-1的相关性。方法:对安图A2000系统检测IGFBP3的精密度(CV)、线性范围、可报告范围、参考区间进行验证。选取2023年1月-2023年9月在本院诊断或治疗的矮小症21例、性早熟10例、垂体性病变19例,回顾性分析其胰岛素生长因子-Ⅰ(IGF-1)和IGHBP3水平,并进行Spearman相关性分析。结果:IGFBP3高低水平质控品批内CV为2.019%、2.931%,批间CV为3.818%、4.137%;测定结果在0.3~16.0μg/mL范围内呈线性,线性回归方程为Y=0.9995X~0.0213,R2=0.9974;临床可报告范围为0.3~32.0μg/mL;18~70岁和>70岁健康体检者检测结果均在厂家提供的参考区间内;IGFBP3和IGF-1在矮小症、性早熟和垂体性病变患者中具有较好的相关性(r=0.81,P<0.0001)。结论:安图A2000检测血清IGFBP3的性能能够满足实验室质量要求,且与IGF-1具有较好的相关性。

用于CCUS油藏压井的环境响应型暂堵剂研制与应用

目前我国CCUS技术正在各油田大规模推广应用。由于CO_(2)对井筒腐蚀十分严重,修井工作量逐年增大,亟需研发压井暂堵剂,对井筒目标层段油气进行暂堵,以有效压井,保障顺利完成修井,修井后暂堵剂自动解堵,快速恢复生产。文中提出环境响应型暂堵剂的研究思路,暂堵剂由聚丙烯酰胺(HPAM)、有机铬交联剂A、活性交联剂B、GB-01破胶剂组成,在复合交联剂作用下快速成胶,并保持3 d左右的高强度和稳定性,实现有效暂堵压井。修井完成后,暂堵剂在微量破胶剂作用下迅速实现环境响应破胶(高温、高矿化度、高CO_(2)含量),2~5 d内完全解堵,从而快速恢复生产。该暂堵剂在吉林油田某井进行了现场试验,效果较好。环境响应型暂堵剂的研究思路具有可行性,也为我国CCUS油藏压井暂堵技术的现场应用提供了参考。

基于XGBoost-Bin自动功率极限计算的风电机组健康性能评估及预测

针对数据量较大情形下风电机组健康性能评估区域难划分、健康性能预测精度低等问题,提出基于XGBoost-Bin的自动功率曲线极限算法,建立考虑多数据特征的机组健康性能预测模型。提出一种基于XGBoost-Bin的曲线构建算法,获取表征风电机组运行状态的静态最优功率曲线;提出一种改进自动功率曲线极限计算的风电机组健康性能评估方法,以准确划分机组健康性能评估区域,并通过综合分析实际与理论静态最优功率曲线偏差、发电效能等指标评估机组健康性能;提出基于多数据特征广义回归神经网络的风电机组健康性能预测模型,以提升健康性能的预测精度。最后,以内蒙古塞罕坝风电场20台风电机组为例表明,与传统自动功率曲线极限计算方法相比,所提风电机组健康性能评估方法的评估准确度提升了0.1026,所提预测模型能够提升机组健康性能的预测精度,比传统随机森林预测模型R2提升了0.017。

心电图机性能的对比验评

为客观评估国产和进口心电图机设备的水平和差异情况,该研究深入对比验评了5台国产心电图机和1台进口心电图机的性能指标及可靠性。结果表明,国产样机的低频特性、对心电图波形间期和时限的自动测量准确性次于进口样机,但高频响应、基线稳定性、抗噪声自动测量稳定性优于进口样机。其他项测试的性能指标在国产和进口心电图机样机间并无明显不同。通过分析国产样机和进口心电图机的对比结果,可在一定程度上反映出目前国产心电图机设备与进口设备间的差异,为国产心电图机设备的研发改进提供参考。

基于深度学习的人工智能模型自动量化超声心动图左心室射血分数初步探索

目的 利用超声心动图静态视图,构建一种基于深度学习的人工智能模型,以自动量化左心室射血分数(LVEF)。方法 将1 902例成人左心室收缩末期和舒张末期的多切面超声心动图视图数据纳入本研究。将收集的数据集分为开发集(1 610例,其中1 252例用于模型训练,358例用于参数调整)、内部测试集(177例,用于内部验证)和外部测试集(115例,用于外部验证和泛化性检测)。该模型通过精确识别左心室心内膜边界和关键点检查,实现左心室分割和自动量化LVEF。采用Dice系数评估左心室分割模型的性能;采用Pearson相关系数和组内相关系数评估自动测量的LVEF与参考标准的相关性和一致性。结果 左心室分割模型性能良好,内部和外部独立测试集的Dice系数均≥0.90;自动测量的LVEF与心脏专家人工测量的一致性中等,内部测试集的Pearson相关系数为0.46~0.71,组内相关分析一致性为0.39~0.57;外部测试集的Pearson相关系数为0.26~0.54,组内相关分析一致性为0.23~0.50。结论 本研究构建了一种性能较好的左心室分割和关键点检测模型,但初步应用该模型自动定量LVEF的效能一般,尚需进一步优化算法,提高模型泛化性。

全自动生化分析仪(XC2000)关键性能验证分析

目的:验证分析四川新健康成生物股份有限公司(新健康成)自主研制的全自动生化分析仪(型号:XC2000)的关键性能。方法:按照行业标准YY/T0654-2017的要求,对A、B、C三台XC2000仪器的光学性能、温度控制及临床项目批内重复性等关键性能指标进行验证分析。结果:三台XC2000仪器内外圈的光学性能(如吸光度线性范围、吸光度准确度等)、温度控制(反应区温度准确性与波动)以及临床项目批内重复性(批内变异系数CV)均符合行业标准规定要求。结论:XC2000全自动生化分析的关键性能指标均到达行业标准规定的要求,为医疗机构国产替代进口提供了重要选择依据。

一种综合赋权的算法性能评价体系

针对当前自动目标识别算法的性能评价指标过于单一的问题,以行人检测作为应用背景下进行了相关研究。论文设计了一套基于AHP(层次分析法)与CRITIC赋权法的目标识别算法性能评价指标体系。该指标体系针对目标识别算法的准确性、时效性、适应性设计了多个性能评价指标,并综合主观赋权法与客观赋权法对评价指标进行赋权。实验测试结果与ImageNet等计算机视觉挑战赛中person类别的检测排名基本吻合,证实论文提出的性能评价体系可靠。

城市轨道交通智慧乘务综合服务系统

[目的]为实现司乘管理由人工方式向智能方式转变,实现智能排班、自动派班等功能,进而提升管理效能,提出了适用于城市轨道交通运营管理的智慧乘务综合服务系统。[方法]定义了智慧乘务综合服务系统的系统架构和功能需求,分析了该系统的内外部接口要求,给出了该系统各子模块的技术方案,介绍了该系统在上海轨道交通10号线的示范应用情况。[结果及结论]应用表明,该系统可提高司机生产率,降低人车比,有助于实现乘务管理提质增效。