Simulation on a Car Interior Aerodynamic Noise Control Based on Statistical Energy Analysis

How to simulate interior aerodynamic noise accurately is an important question of a car interior noise reduction. The unsteady aerodynamic pressure on body surfaces is proved to be the key effect factor of car interior aerodynamic noise control in high frequency on high speed. In this paper, a detail statistical energy analysis （SEA） model is built. And the vibra-acoustic power inputs are loaded on the model for the valid result of car interior noise analysis. The model is the solid foundation for further optimization on car interior noise control. After the most sensitive subsystems for the power contribution to car interior noise are pointed by SEA comprehensive analysis, the sound pressure level of car interior aerodynamic noise can be reduced by improving their sound and damping characteristics. The further vehicle testing results show that it is available to improve the interior acoustic performance by using detailed SEA model, which comprised by more than 80 subsystems, with the unsteady aerodynamic pressure calculation on body surfaces and the materials improvement of sound/damping properties. It is able to acquire more than 2 dB reduction on the central frequency in the spectrum over 800 Hz. The proposed optimization method can be looked as a reference of car interior aerodynamic noise control by the detail SEA model integrated unsteady computational fluid dynamics （CFD） and sensitivity analysis of acoustic contribution.

基于混合马尔科夫树模型的ICS异常检测算法

针对工业控制系统中现有异常检测算法在语义攻击检测方面存在的不足,提出一种基于混合马尔科夫树模型的异常检测算法,充分利用工业控制系统的阶段性和周期性特征,构建系统正常运行时的行为模型|混合马尔科夫树.该模型包含合法的状态事件、合法的状态转移、正常的概率分布以及正常的转移时间间隔等4种信息,基于动态自适应的方法增强状态事件的关联度并引入时间间隔信息以实现对复杂语义攻击的检测,语义建模时设计一种剪枝策略以去除模型中的低频事件、低转移事件以及冗余节点,当被检测行为使得模型的以上4种信息产生的偏差超过阈值时,判定该行为异常.最后,基于OMNeT++网络仿真环境构建一个简化的污水处理系统对本文算法进行功能性验证,并利用真实物理测试床的数据集对算法的检测准确度进行性能验证.验证结果表明,本文算法能有效消除人机交互和常规诊断等操作带来的噪声影响,对复杂语义攻击具有较高的检出率,且能识别传统的非语义攻击.

SP800-82《工业控制系统(ICS)安全指南》研究

介绍了SP 800-82《工业控制系统(ICS)安全指南》的主要内容,分析了工业控制系统的漏洞和主要威胁,以及如何为ICS建立安全程序,详细阐述了ICS如何应用SP 800-82。

EICS信息安全内涵及与传统IT系统差异分析

为了准确研究电力工业控制系统(Electric Industry Control System,EICS)信息安全,文章从狭义信息安全和广义信息安全角度,分别分析其内涵和外延,对于狭义信息安全提出一种形式化定义,对于广义信息安全提出图形化表示;通过对比分析EICS与传统信息技术(Information Technology,IT)系统在信息安全方面的区别,提出EICS不同于传统IT系统的主要特点,阐述了EICS信息安全内涵,最后描述推荐的EICS信息安全定义。文章的研究将有助于相关研究工作的全面深入开展。

基于G1-ICS算法的磁流变半主动悬架最优控制

根据车辆行驶动力学特性,建立了包含座椅的三自由度1/4半主动悬架模型,采用BP神经网络建立了磁流变阻尼器逆向模型。针对磁流变半主动悬架各项性能指标,以座椅性能为主要优化目标,应用最优控制理论设计了线性二次型最优控制器。分别采用序关系分析法(G1法)以及与改进布谷鸟搜索算法(G1-ICS)相结合的方法确定了各性能指标加权系数,并在Matlab/Simulink中对磁流变半主动、被动悬架模型进行了仿真验证。结果表明:与被动悬架相比,两种算法均能在一定程度上改善悬架系统的性能,尤其是悬架系统座椅性能;同时,采用两种方法相结合的方式能更进一步提高磁流变半主动悬架性能。

Application of neural networks for permanent magnet synchronous motor direct torque control

Neural networks require a lot of training to understand the model of a plant or a process. Issues such as learning speed, stability, and weight convergence remain as areas of research and comparison of many training algorithms. The application of neural networks to control interior permanent magnet synchronous motor using direct torque control （DTC） is discussed. A neural network is used to emulate the state selector of the DTC. The neural networks used are the back-propagation and radial basis function. To reduce the training patterns and increase the execution speed of the training process, the inputs of switching table are converted to digital signals, i.e., one bit represent the flux error, one bit the torque error, and three bits the region of stator flux. Computer simulations of the motor and neural-network system using the two approaches are presented and compared. Discussions about the back-propagation and radial basis function as the most promising training techniques are presented, giving its advantages and disadvantages. The system using back-propagation and radial basis function networks controller has quick parallel speed and high torque response.

A 1.1GHz LC VCO with Automatic Amplitude Control for Tuner Applications

This paper presents an LC VCO with auto-amplitude control （AAC）, in which pMOS FETs are used,and the varactors are directly connected to ground to widen the linear range of Kvco. The AAC circuitry adds little noise to the VCO but provides it with robust performance over a wide temperature and carrier frequency range.The VCO is fabricated in a chartered 50GHz 0.35μm SiGe BiCMOS process. The measurements show that it has - 127. 27dBc/Hz phase noise at 1MHz offset and a linear gain of 32.4MHz/V between 990MHz and 1.14GHz.The whole circuit draws 6. 6mA current from 5V supply.

Active Noise Control of the Heavy Truck Interior Cab

In order to control the noise of the heavy truck interior cab effectively, the active noise control methods are employed. First, an interior noise field test for the heavy truck is performed, and frequencies of interior noise of this vehicle are analyzed. According to the spectrum analysis of acquired noise signal, it is found out that the main frequencies of interior noise are less than 800Hz. Then the least squares lattice （LSL） algorithm is used as signal processing algorithm of the controller and a closed-loop control DSP system, based on TMS 320VC5416, is developed. The residual signal at driver＇s ear is used as feedback signal. Lastly, the developed ANC system is loaded into the heavy truck cab, and controlling the noise at driver＇ s ear for that truck at different driving speeds is attempted. The noise control test results indicate that the cab interior noise is reduced averagely by 0.9 dBA at different driving speeds.

Nonlinear Control of Interior PMSM Using Control Lyapunov Functions

In this paper, we introduce a non-linear torque control for an interior permanent-magnet synchronous motor (IPMSM). The nonlinear control is based on a Control Lyapunov Function (CLF) technique. The proposed stabilizing feedback law for the IPMSM drive is a damping control method and is shown to be globally asymptotically stable. The CLF method takes the system nonlinearities into account in the control system design stage. Such nonlinearities are due to the cross coupling between the q and the q currents in addition to the system parameters like the inductances and the flux linkages. The complete IPMSM drive incorporating the proposed CLF has been successfully simulated in a plant model for both motor and inverter. The performance of the proposed drive is investigated in simulation at different operating conditions. It is found that the proposed control technique provides a good torque control performance for the IPMSM drive ensuring the global stability. In later work, we are planning to investigate other phenomena such as magnetic saturation, nonlinear loads, mechanical friction and flexibilities.

RRCNN: Request Response-Based Convolutional Neural Network for ICS Network Traffic Anomaly Detection

Nowadays,industrial control system(ICS)has begun to integrate with the Internet.While the Internet has brought convenience to ICS,it has also brought severe security concerns.Traditional ICS network traffic anomaly detection methods rely on statistical features manually extracted using the experience of network security experts.They are not aimed at the original network data,nor can they capture the potential characteristics of network packets.Therefore,the following improvements were made in this study:(1)A dataset that can be used to evaluate anomaly detection algorithms is produced,which provides raw network data.(2)A request response-based convolutional neural network named RRCNN is proposed,which can be used for anomaly detection of ICS network traffic.Instead of using statistical features manually extracted by security experts,this method uses the byte sequences of the original network packets directly,which can extract potential features of the network packets in greater depth.It regards the request packet and response packet in a session as a Request-Response Pair(RRP).The feature of RRP is extracted using a one-dimensional convolutional neural network,and then the RRP is judged to be normal or abnormal based on the extracted feature.Experimental results demonstrate that this model is better than several other machine learning and neural network models,with F1,accuracy,precision,and recall above 99%.

ICS Trusted系统在旋转机械安全控制中的应用

简要介绍了安全控制系统的核心,详细介绍了ICS Trusted系统的硬件、软件、防喘振控制软件包、综合机组控制(ITCC)、紧急停车装置(ESD)的功能特点和主要组成。并基于ICS Trusted系统设计实现了某压缩机组的安全控制,在运行过程中展现了良好的控制性能和经济性。

The Non-Singular Fast Terminal Sliding Mode Control of Interior Permanent Magnet Synchronous Motor Based on Deep Flux Weakening Switching Point Tracking

This paper presents a novel non-singular fast terminal sliding mode control(NFTSMC)based on the deep flux weakening switching point tracking method in order to improve the control performance of permanent interior magnet synchronous motor(IPMSM)drive systems.The mathematical model of flux weakening(FW)control is established,and the deep flux weakening switching point is calculated accurately by analyzing the relationship between the torque curve and voltage decline curve.Next,a second-order NFTSMC is designed for the speed loop controller to ensure that the system converges to the equilibrium state in finite time.Then,an extended sliding mode disturbance observer(ESMDO)is designed to estimate the uncertainty of the system.Finally,compared with both the PI control and sliding mode control(SMC)by simulations and experiments with different working conditions,the method proposed has the merits of accelerating convergence,improving steady-state accuracy,and minimizing the current and torque pulsation.

T-Helper I Cell/T-Helper 2 Cell Balance with Anti Inflammatory Therapy in Partly Controlled Asthmatic Children

The authors aimed to assess Thl （T-helper cell 1）/Th2 （T-helper cell 2） balance, through evaluation of serum IFN-γ （interferon gamma） and IL-4 （interleukin 4）, during asthma exacerbation and study the effect of anti inflammatory therapy. A randomized prospective case-control study was designed. The sludy included 30 asthmatic patients, aging 8-14 years. All were diagnosed as partly controlled asthmatics. Twenty, age and sex matched, healthy children were included in the study as control group All participants were subjected to medical history, clinical examination, pulmonary function testing, eosinophilic blood counting, estimation of serum interleukine-4 and interferon gamma. Patients were treated for 6 weeks with 2 different anti inflammatory drugs. All methods were then repeated for follow up. IL-4 serum level was significantly higher in subjects with partly controlled asthma than in control subjects （P = 0.01）, and then in asthmatic patients after therapy （P = 0.0000）, while IFN-）, serum level was significantly lower in subjects with partly controlled asthma than in control subjects （P = 0.01）, and than in asthmatic patients after therapy （P = 0.0000）. Interferon gamma showed a significant negative correlation with IL-4 among the healthy control group （r = -0.559, P = 0.010）. Both LTA （leukotriene antagonist） and ICS （inhaled corticosteroids） therapy lead to significant improvement, but there were no statistically significant differences （P 〉 0.05） between them as regard the pulmonary functions and the laboratory evaluating parameters. Both serum levels of IL-4 and IFN-γ, could be used as a reliable inflammatory biomarker for the evaluation and follow up of asthmatic patients.

GENETIC TYPES AND CHARACTERISTICS OF GROUND ICE IN NORTHEAST CHINA

The southern limit of permafrost in northeast China oversteps that in the other regions of Eurasia by a few degrees of latitude. There are 11 types of ground ice found within the studied region, including vein ice, massive bedrock ice, lava caves ice and so on. The water for the formation of the ground ice comes from various sources: precipitation, surface water, soil water, and ground water. The ground ice types coexist with the surrounding environment. The correlation and distribution features of the original types of ground ice, their surrounding environments are analyzed for the theoretical study of ground ice formation, engineering control of hazards in ice rich areas and the prediction of changing conditions.

Energy-Saving and Control of General Indoor Lighting Elements Fed from a Micro-Controlled Hybrid Power Generation System

In this study, an off grid wind-solar hybrid power generation system was established at Afyon Kocatepe University to meet the energy need of lighting system of three different laboratories. It is planned to efficiently use the energy obtained from the designed hybrid power generation system. For this purpose, PIC 16F877 was used in controlling of lighting load of laboratories. The off-grid wind-solar hybrid power generation system consists of 570 W 24 V mono crystal solar panels, 600 W wind power generation system and accumulator groups. The load control circuit made with PIC 16F877 is designed in a manner that will control the lighting armature groups individually activate and deactivate the armature groups according to intensity of illumination in environment. Besides, separately from generation and storing units constituting the hybrid power generation system, data in kWh are recorded by means of software in 10 seconds intervals. With the obtained power generation and storing data, analyzing of power consumption data when the load control system in active or passive position is made. According to analysis results, with controlling of lighting load and using of energy obtained from off grid wind-solar hybrid power generation system, 20.6% energy saving has been ensured.

Numerical Simulation of Turret Moored Ship Performance in Variable Ice Drift Based on Heading Control

The frequent change in ice drift direction poses a significant challenge for turret moored ship in ice. Variability in ice drift is mainly caused by the winds and currents. To solve this problem, a new method with numerical simulation based on heading control is applied to reduce the risk of operation of The Arctic Tandem Offloading Terminal(ATOT),which includes an offloading icebreaker(OIB) moored to a submerged turret and a shuttle tanker moored at the stern of the OIB in this paper. An icebreaking tanker, MT Uikku, was modeled in a simulation program. Then the level ice load on the tanker was calculated with different ice thicknesses and drift speeds, after which a heading controller assisted with mooring system is used to simulate the horizontal motion of the tanker under the ice action.

昂宝电子推出一系列高性能CCFL Controller IC

近日，昂宝电子推出一系列CCFL Controller IC，可广泛用于LCD-Monitor、LCD—TV、Notebook以及工业设备、汽车、手持设备中的液晶显示器。昂宝的系列芯片具有其鲜明的特点：整个系列芯片具有高精度的电压参考和频率控制，均支持系统宽电压输入，灵活的系统参数设定可以满足客户对系统设计的不同要求。

Self-Structured Organizing Single-Input CMAC Control for De-icing Robot Manipulator

This paper presents a self-structured organizing single-input control system based on differentiable cerebellar model articulation controller (CMAC) for an n-link robot manipulator to achieve the high-precision position tracking. In the proposed scheme, the single-input CMAC controller is solely used to control the plant, so the input space dimension of CMAC can be simplified and no conventional controller is needed. The structure of single-input CMAC will also be self-organized;that is, the layers of single-input CMAC will grow or prune systematically and their receptive functions can be automatically adjusted. The online tuning laws of single-input CMAC parameters are derived in gradient-descent learning method and the discrete-type Lyapunov function is applied to determine the learning rates of the proposed control system so that the stability of the system can be guaranteed. The simulation results of three-link De-icing robot manipulator are provided to verify the effectiveness of the proposed control methodology.

简述XLX ROV的ICE控制系统及其应用

文章主要讲述了一款全球主流使用重工作级XLX ROV的ICE(integrated controls engine)控制系统信号的传输方式,介绍了该系统内各模块的运作方式、作用及内部联系。此外,文中详细介绍了指令如何从水上传递至水下进而控制ROV的动作,文中还结合实际应用中的案例分析了其在应用中的众多优缺点。

维护ICS14式皮带秤日常使用精度的分析和措施

ICS皮带秤作为计量设备的重要一员,被广泛应用于大宗散货计量工作中,是装卸、堆存管理、交易等活动的重要依据。在日常使用过程中不难发现,无论皮带秤本身精度多高,安装多标准,都会或多或少的出现实际计量精度超标的情况,不符合使用需求。本文从实际应用出发,着重分析影响ICS皮带秤使用精度的主要因素,提出了对应的解决方案,对维护使用精度有较大的作用。