Multi-object Optimization Design of Engine Mounting System Parameters

A multi-object optimization model is proposed with respect to the completed vehicle in ergonomics,which takes the root-mean-square value of body in multiple work condition and the decoupled energy of engine mounting system as a general object. The optimization values is given. An example shows that the vibration of an automobile can be reduced effectively by choosing proper parameters of mounting system.Moreover, comfort of automobile can be improved.     

Design of Analysis and Evaluation Application System for Ride Comfort

The stimulation and the optimal design for bus ride comfort have played an importable roles in design and reform of automobile products. The new vibration comfort coefficient is applied to evaluate the ride comfort of automobile, and the software is developed. It is verified that the study has theoretical and practical value significantly.     

Robust H control for vehicle seat suspension systems with stochastic disturbance

The paper proposes the design method of robust H controller of vehicle seat suspension system. The dynamic model of seat suspension is developed,and the parameters uncertainties (mass, stiffness, damping) and stochastic vibration are introduced into the model system. Based on stochastic differential theory and Lyapunov functional, a semi controller is designed, and the controller parameters are solved by linear matrix inequality (LMI) which guarantees H performance index. The simulation results in time domain and frequency domain show that the controller designed for parameter uncertainties and stochastic vibration can attenuate the vertical acceleration of suspension system and improve riding comfort of human.     

Subjective Evaluation of Motorcycle Ride Comfort

The ride comfort of more than ten representative motorcycles is evaluated by the r. m. s acceleration value through road test. Then the investigation on ride comfort, with five grades, is carried out through these motorcycles rode by a dozen drivers. Using statistics and fuzzy mathematical methods, the fuzzy evaluation model of motorcycles ride comfort is built to discuss the relationship between the vibration magnitude and human reaction. Finally, according to this model, two motorcycles ride quality are evaluated.     

Simulation and analysis of all terrain vehicle ride comfort

A multi rigid body dynamic model of an all terrain vehicle (ATV) is established in MSC.ADAMS. The model takes into consideration the body, suspension, frame and the steering system. According to the method of superposition of harmonic wave, a Grade B road file is created in ADAMS for the riding comfort test. The engine excitation is analyzed. The infliction for engine excitation to ADAMS is achieved. The ATV ride comfort simulation is carried out with the excitation of the engine, and the seat vibration is evaluated using an evaluation method programmed via MATLAB. It has laid a good foundation for further analysis.     

体育馆大跨度预应力次梁楼盖竖向振动模态分析

以重庆市铜梁县新城核心区小学建设项目3^#楼（体育馆）工程为背景，对其大跨度预应力次梁楼盖竖向振动模态进行模拟分析，并与实测结果相比较，评价其控制竖向振动舒适度的效果。根据建模思路精确建立的该大跨楼盖有限元模型，其模态分析结果与模态实测结果接近，相对误差约为5%；模拟分析及工程实测结果表明，该大跨楼盖前三阶振型均以竖向振动为主，结构自振基频满足我国现行相关规范的要求，竖向振动舒适度符合标准；与无底板的大跨次梁楼盖相比，增加底板后，其增幅最小的一阶频率增长了19.9%，表明增加底板可有效地控制大跨度预应力次梁楼盖的竖向振动。     

Electre Multi-Attribute Evaluation Model to the Operating Performance of Air Conditioning Systems

An ELECTRE performance evaluation model was developed to outrank the different operating conditions of air conditioning systems. Five evaluation criteria covers total energy consumption, thermal comfort PMV and PPD, indoor air quality indices such as CO2 concentration and TVOC concentration. The performance under seven different operating conditions was outranked on the TRNSYS (transient system) simulation platform. Three assignment alternatives of weight coefficients were selected to calculate the relevant credibility scores respectively. The results indicate that the proposed evaluation model can outrank the different operating conditions and select the optimum one, Moreover different weight assignments have little influence on the outranking scores. Further investigation should focus on the more evaluating criteria such as control performance and others in the comprehensive evaluation of operating conditions.     

Analysis of Fuzzy Control Strategy Based on Energy and Peak Value of Vibration

The effect of damping on vibration is analyzed during the suspension deformation based on the 1/4 vehicle model. The Fuzzy logic control strategy for the semi-active suspension was proposed. By means of dissipating the energy of vibration and decreasing the peak value of the body acceleration via the action of damping, the parameter-self-adjust fuzzy controller was established. The united simulation of ADAMS and Matlab/Simulink were used for demonstrating the efficiency of the controller. Comparing with the practical passive suspension possessing the nonlinear character and the present fuzzy controller, the control system based on the new-style strategy provides better ride comfort and road handling.     

基于累积时数的夏季人居环境舒适度评判模型研究—以宁波市为例

舒适度是人居环境的重要评判指标。利用宁波市1957-2016年逐日气象数据和2005-2016年逐时气象数据,对宁波市夏季舒适度变化特征及其对气温要素的响应进行分析,开展了基于舒适等级累积时数的日舒适度评判模型研究。结果表明：宁波市60a夏季舒适日数年际间波动变化不明显,但夏季不舒适日开始时间提前趋势明显;舒适度指数日变化与气温日变化趋势相似,13时最不舒适;宁波市夏季舒适日数与平均气温、平均最低气温、平均最高气温、极端最高气温和高温日数显著相关;利用线性拟合结果,建立了基于舒适等级累积时数的宁波市夏季日舒适度评判模型,对模型分别进行历史资料回代模拟和2016年一致性验证,舒适和不舒适等级历史回代一致率较高,2016年模型验证中各等级一致率均在91.7%以上,表明新模型评判效果较好,能够满足业务服务需求。     

基于主成分分析的BP神经网络估算藏北高寒草地覆盖度变化

藏北高寒牧区草地是中国高寒草地分布面积最大的地区。为了及时准确地获得该区域草地覆盖度的变化趋势,本研究利用多年气象数据、社会统计数据、GIMMS、MODIS两种归一化植被指数（NDVI）数据作为参数,构建 BP神经网络模型,估算2010—2014年藏北高寒草地年际变化趋势,并用主成分分析方法优化参数来改进模型。结果表明,① BP神经网络模型及其改进模型对藏北高寒草地覆盖度年际变化趋势与遥感值的相关系数为0.16、0.47,表明通过主成分分析优化参数后的BP神经网络模型具有较好的模拟效果。 ②两种BP神经网络估算的植被指数值与NDVI值平均误差率分别为2.36%、2.20%。均有较高的模拟精度。③从神经网络训练步数上看,BP神经网络结果训练收敛步长为5000,基于主成分分析的BP神经网络模型训练收敛步长为454,表明后者提高了计算效率,体现出良好的收敛性。因此,无论从年际变化趋势拟合程度、植被指数估算值精度、还是从计算效率来看,改进的BP神经网络模型对于估算藏北高寒草地覆盖度变化更加行之有效。     

Synthetic Control Strategy for a Car With Hydro-mechanical Continuously Variable Transmission System at Standing Start

Continuously variable transmission (CVT) is the ideal transmission for automobile, it is also one of the most important research items of researchers and automobile companies all over the world. The dynamic simulation model is established and integrated control strategy of standing start is proposed for dual mode CVT vehicle, aiming at automatic vehicle with torque converter as a starter and metal pushing belt as a higher transmission equipment (Dual mode CVT vehicle), on the base of engine and torque converter performance experiment. Simulation result shows that vehicle performance can be improved by using the control strategy proposed. The research results provide the theory method of analyzing and designing for CVT vehicle.     

考虑预估驾驶行为的跟驰模型及其稳定性分析

在OV模型的基础上,进一步考虑预估驾驶行为对车流的影响,提出一个新的跟驰模型以获得预估驾驶行为与交通拥堵的关系。通过对新模型进行稳定性分析得到了系统的临界稳定条件。数值仿真结果表明：新模型能够模拟诸如时停时走、系统临界相变等实际交通现象,较OV模型更贴近于实际。同时,预估驾驶行为增强了交通流稳定性能,提高了车流陷入交通阻塞状态的阈值。最后以车速的平滑度和波动幅度最小为评价指标得到了新模型中预估参数的最优取值范围。     

Objective Evaluation Methods for ATV Ride

To make up the vacancy of the evaluation methods for ATV ride in the world, the pratical feature of ride comfort of ATV are studied and analyzed. Based on the ISO2631 and ISO5349, the objective methods of ride com-fort of ATV are proposed. This method uses the total root mean square of weighed of three axles to evaluate the vibration of the handle and seat. Road tests and experiments on rolling drum experiment table with the test system on ride comfort of some typical ATVs are conducted, the result of the two tests are matched each other, so the evaluation method can well reflect the effects of the vibration on human body.     

Study on Vibration Performance of Engineered Wood Truss Joist Floors

In recent years wood trusses are widely used in buildings due to their excellent performance and ease of construction. As with solid lumber joists, however, the vibration of wood truss joist floors can cause occupants to feel discomfort. To understand the relationship between the vibration performance of wood truss joist floors and the perceptions of occupants, experimental and subjective evaluations were conducted on six truss joist floors. The results show there is close relationship between perceptions of occupants and the fundamental natural frequency, static deflection and vibration acceleration of truss joist floors. The installation of bracings and straps greatly improved the vibration performance of light truss joist floors. We suggest that two or more factors should be included in the design criteria for controlling wood floor vibration, such as static deflection and fundamental natural frequency. Peak acceleration can be adopted as a factor in the evaluation system of vibration performance of wood truss joist floors.     

一种新的符合度算法及其应用

在总结分析了几种常用综合评价方法的基础上, 提出了一种反映观察值与理论值之间相似性的新算法--符合度。该算法就评价信息个体(观察值)与标准值(期望值)的马氏距离, 再由马氏距离转化为评价对象与标准的接近程度, 即符合度(r)。首先进行指标数(p)、相似度(r)与马氏距离(d)的模拟试验, 再通过曲面拟合的方法找出它们之间的关系模型。通过大量抽样试验, 验证符合度的次数分布与原先设定的符合度的良好对应关系, 说明模型的可行性与可靠性。以小麦RVA性状为指标, 利用该算法分析扬麦系统若干品种之间的接近程度, 并评价多变数复杂效应回归分析模拟试验的结果。符合度算法不需要数据标准化处理, 直接利用原始数据, 减少了计算工作量, 降低了因数据标准化处理方法不同而引起的评价结果差异, 同时由于不需要赋权, 排除了主观性的影响, 保证了信息的完整性以及评价结果的可靠性。     

居住建筑室内热环境低能耗营造的多目标设计方法

人居环境改善涉及重大民生问题,节能减排是国家重大战略。因此,有必要寻求合理的居住建筑设计方法,使设计方案既满足居民的室内热舒适需求又能降低建筑能耗。基于多目标遗传优化算法,建立能够对建筑设计方案进行优化、实现增加室内热舒适时间比例的同时降低建筑全年冷热负荷的居住建筑设计双目标优化模型。最后,以重庆典型户型为实例进行优化,优化后的设计方案建筑全年冷热负荷降低了47.74%,室内热舒适时间比例提高了3.94%,验证了模型的可行性和准确性。     

Wind Vibration Analysis on the Large -span Curtain Wall

The large-span structure requires wind vibration analysis when computing the wind load;however,the formula in current code on wind vibration coefficient can hardly be applied in large-span structure,making its computation difficult and troublesome.This paper makes wind vibration analysis on the large-span curtain wall combined with certain engineering background in the methods of both time domain and frequency domain,and then the derived results are compared.The analytical results demonstrate identical distribution and contiguous numerical value of wind vibration coefficient concluded from the two varied methods;furthermore,even if the method in time domain is higher in computational complexity,more data on the response of structure under wind can be obtained,which provides reference for the theoretical analysis and engineering design.     

切割片减振降噪的优化设计

为了研究切割片在工作过程中的振动及噪声问题,基于有限元方法,借助于ANSYS APDL有限元软件建立了切割片有限元模型;采用反转法施加载荷,简化模型及分析过程,在振动特性分析中,得出调整切割片结构参数可以降低切割片振动幅度的结论;基于振动能量与速度的平方关系,以测试点的速度平方和为目标函数,设计了优化程序对切割片模型进行调整优化,获得了一组最优调整数据,为实际生产提供了参考依据。     

Robust Control System for the Optical Extra-precise Vibration Isolation System

The robust control theory is used to solve the uncertainty of the optical extra-precise vibration isolation system. The wavelet theory is used to analyze the random vibration signal in the time-frequency domain and get the low frequency signal from the random vibration signal. The robust controller designed by the robust control theory is used to restrain the low frequency vibration. The active vibration isolation exploits the theory of robust control, which overcomes the uncertainty of model and the disturbance, and makes the control system to restrain the uncertainty of the model and the disturbance of the vibration. The simulation results prove that this method has shown good robustness and control precision in the vibration isolation of the optical extra-precise instrument and have good performance on restraining the low frequency vibration.     

Design Methods to Control Vibration of Solid Lumber Joist Floors

Timber floors are by far the most common structural systems used in wood-framed residential buildings,and are the only systems with which human occupants are in constant physical contact.In dwellings,the floor vibration due to walking often brings discomfort to the occupants.Designing a house that controls the agonizing vibration of floors is a difficult problem.The vibration performance of five solid wood lumber joist floors was studied as were subjective opinions of evaluators.The 1KN static deflection and fundamental natural frequency were selected as two evaluation indexes of the vibration performance.The results show that when the ratio of the fundamental natural frequency to 1KN static deflection's 0.44 power is larger than 20,the solid wood lumber joist floor can be classiified as acceptable.