Programmable Logic Controller Block Monitoring System for Memory Attack Defense in Industrial Control Systems

Cyberattacks targeting industrial control systems(ICS)are becoming more sophisticated and advanced than in the past.A programmable logic controller(PLC),a core component of ICS,controls and monitors sensors and actuators in the field.However,PLC has memory attack threats such as program injection and manipulation,which has long been a major target for attackers,and it is important to detect these attacks for ICS security.To detect PLC memory attacks,a security system is required to acquire and monitor PLC memory directly.In addition,the performance impact of the security system on the PLC makes it difficult to apply to the ICS.To address these challenges,this paper proposes a system to detect PLC memory attacks by continuously acquiring and monitoring PLC memory.The proposed system detects PLC memory attacks by acquiring the program blocks and block information directly from the same layer as the PLC and then comparing them in bytes with previous data.Experiments with Siemens S7-300 and S7-400 PLC were conducted to evaluate the PLC memory detection performance and performance impact on PLC.The experimental results demonstrate that the proposed system detects all malicious organization block(OB)injection and data block(DB)manipulation,and the increment of PLC cycle time,the impact on PLC performance,was less than 1 ms.The proposed system detects PLC memory attacks with a simpler detection method than earlier studies.Furthermore,the proposed system can be applied to ICS with a small performance impact on PLC.

Design and application of automatic constant temperature moxibustion box

目的:探讨自行设计的全自动恒温艾灸箱的临床应用效果。方法:以2016年6月至2017年1月,我院收治的颈、肩、背、腿疼痛患者150例为研究对象,将患者随机分为对照组和观察组,每组各75例。其中,对照组患者随机接受传统艾灸盒治疗,观察组自动恒温艾灸箱治疗,治疗周期为15天。治疗结束后对患者的安全性、舒适度、满意度、不良反应进行比较,使用SPSS20统计软件对结果进行分析。结果:观察组患者舒适度和满意度均优于对照组患者,差异有统计学意义(P<0.01);在安全性方面,对照组患者发生烫伤的比例为5.3/100,观察组为0。结论:全自动恒温艾灸箱临床使用方便,操作简便,安全性高。对提高临床疗效,防范医疗风险具有重要意义,值得临床应用。

HRPDF: A Software-Based Heterogeneous Redundant Proactive Defense Framework for Programmable Logic Controller

Programmable logic controllers(PLCs)play a critical role in many industrial control systems,yet face increasingly serious cyber threats.In this paper,we propose a novel PLC-compatible software-based defense mechanism,called Heterogeneous Redundant Proactive Defense Framework(HRPDF).We propose a heterogeneous PLC architecture in HRPDF,including multiple heterogeneous,equivalent,and synchronous runtimes,which can thwart multiple types of attacks against PLC without the need of external devices.To ensure the availability of PLC,we also design an inter-process communication algorithm that minimizes the overhead of HRPDF.We implement a prototype system of HRPDF and test it in a real-world PLC and an OpenPLC-based device,respectively.The results show that HRPDF can defend against multiple types of attacks with 10.22%additional CPU and 5.56%additional memory overhead,and about 0.6 ms additional time overhead.

Design and Development of Mechatronic Application in Agricultural Irrigation Device

In order to help the small-scale farmer, an automatic irrigation control system was proposed. This system will provide an irrigation system that will ease the burden of the citizen to take care of the plant. This system will run automatically by referring to the time set by the user. As the name itself is a water control system, this system will only start irrigating when the time set triggered the water control level for the plant to grow healthily. It will automatically stop when the timer is off (1 hour). The brain of the system is the PLC (Programmable Logic Controller). This is the place where all the activities are done. The irrigation will be provided by a pump that is also connected to the microcontroller. The pump will be activated until the timer has reached its time set. This system will continue running until the user presses the OFF button.

Fuzzy Controller-Based Design and Simulation of an Automatic Parking System

With the development of automatic driving and fuzzy theory, people pay more and more attention to the application of fuzzy logic in engineering technology. The automatic parking module in the automatic driving system has always been the focus of research. Automatic parking modules can greatly assist drivers in parking operations, greatly reduce parking difficulties and make people more convenient and fast parking. In this paper, an automatic parking system based on the fuzzy controller is proposed. The fuzzy controller of automatic parking system is constructed by using fuzzy theory, and the robustness of the whole system is examined by fuzzy logic. Firstly, the vehicle motion rules and trajectory changes are analyzed in detail, and the real parking lot model is simulated. Then, the input and output variables of the whole system are analyzed by fuzzy theory and the membership function is constructed. Based on the experience of human experts, the parking rules are tested and summarized, and a reasonable and practical rule base is established. Finally, MATLAB is used to code, build the visual interface of parking lot and vehicles, and draw the cyclic iterative function to detect the vehicle position and direction angle, so as to act as a sensor. The results show that using a fuzzy controller to construct an automatic parking system can effectively improve the parking level.

NIPAD： a non-invasive power-based anomaly detection scheme for programmable logic controllers

工业控制系统广泛应用于关键基础设施的建设中,关系到国计民生,因此,攻击者越来越多地将其作为攻击目标,并造成严重的破坏。可编程逻辑控制器(Programmable logic controller,PLC)作为工业控制系统中的核心组件,能够直接控制现场设备,一旦PLC中运行了恶意程序,则可能直接造成重大财产损失甚至是人员伤亡。近些年来,针对PLC的攻击事件显著增加,这表明PLC存在很大的脆弱性,同时也提醒人们保护PLC安全的重要性。不幸的是,传统的入侵检测系统和杀毒软件并不能很好地保护PLC的安全,因此,针对PLC的有效的安全防护方案有待被研究。基于上述背景,本文提出了一种非侵入式的基于功耗的PLC异常检测方案。该方案通过分析PLC运行时的功耗变化来检测PLC中是否运行异常程序,分为功耗信息获取与功耗分析两部分。采集功耗信息是通过在PLC的供电线上串入一个电阻实现的,当PLC运行时,测量电阻两端的电压即可获取CPU的功耗信息。为了更好的分析功耗信息,本文首先从原始功耗数据中提取有效的特征值组合,然后利用正常样本来训练一个基于长短记忆(long short-term memory,LSTM)单元的神经网络模型,利用该模型对后续正常样本进行预测,通过比较测量到的功耗信息与预测的功耗信息,可以确定当前PLC中运行的程序是否为正常程序。该方案的优点是无需对原工控系统的封装部分进行软硬件的修改,且无需负样本即可实现对未知攻击的检测。我们在实验室测试平台上对该方法进行了评估,实验表明,对于原程序,只需改动0.63%即可达到99.83%的准确率。

Synthesis of Nonlinear Control of Switching Topologies of Buck-Boost Converter Using Fuzzy Logic on Field Programmable Gate Array (FPGA)

An intelligent fuzzy logic inference pipeline for the control of a dc-dc buck-boost converter was designed and built using a semi-custom VLSI chip. The fuzzy linguistics describing the switching topologies of the converter was mapped into a look-up table that was synthesized into a set of Boolean equations. A VLSI chip–a field programmable gate array (FPGA) was used to implement the Boolean equations. Features include the size of RAM chip independent of number of rules in the knowledge base, on-chip fuzzification and defuzzification, faster response with speeds over giga fuzzy logic inferences per sec (FLIPS), and an inexpensive VLSI chip. The key application areas are: 1) on-chip integrated controllers;and 2) on-chip co-integration for entire system of sensors, circuits, controllers, and detectors for building complete instrument systems.

A note on diagnosis and performance degradation detection in automatic control systems towards functional safety and cyber security

This note addresses diagnosis and performance degradation detection issues from an integrated viewpoint of functionality maintenance and cyber security of automatic control systems.It calls for more research attention on three aspects:(i)application of control and detection uni ed framework to enhancing the diagnosis capability of feedback control systems,(ii)projection-based fault detection,and complementary and explainable applications of projection-and machine learning-based techniques,and(iii)system performance degradation detection that is of elemental importance for today's automatic control systems.Some ideas and conceptual schemes are presented and illustrated by means of examples,serving as convincing arguments for research e orts in these aspects.They would contribute to the future development of capable diagnosis systems for functionality safe and cyber secure automatic control systems.

Design of precision variable-rate spray system for unmanned aerial vehicle using automatic control method

In order to reduce the use of chemical pesticides in crop plant protection and improve the utilization efficiency of pesticides,it is necessary to study advanced application machinery and application techniques.The use of unmanned aerial vehicle(UAV)for pesticide spraying has the characteristics of less application,strong penetrability,wide applicability and flexible operation scheduling,and has gradually become one of the important development directions in the field of aviation plant protection.However,the operation process of the UAV is often affected by meteorological factors and human manipulation,resulting in poor actual operation with inaccurate spray volume and uneven application.Therefore,to improve the stability and uniformity of the application of the plant protection UAV under variable operating conditions,in this paper a real-time control method was proposed for the application flow rate,and a precision variable-rate spray system was designed based on single-chip microcomputer and micro diaphragm pump that can controls the flow rate of the pump in real time with the changes of the operating state.The response s-peed of the variable-rate spray system was tested.The average control response time of the system was 0.18 s,and the average stability time of the pump flow change was 0.75 s.The test results showed that the system has a quick response to the working state and the adjustment of the target flow of the pump can be quickly completed to realize the variable-rate spray function.The research results can provide a reference for the practical application of plant protection UAV variable-rate spray system.

Synchro Controller of Radar on FPGA

This paper mainly represents the realization of synchro controller based on the programmable logic devices FPGA by request of HF ground wave radar synchro controller under the instance of making the best of the virtues of FPGA. This design introduces the data communication between PC and synchro controller by PC Bus, which can carry the synchronous signals parameters to RAM of synchro controller, then according to the theory that the result of comparing counter value with signals parameters is the needed wave, we produce all waves HF ground wave radar needs, moreover all waves are produced time-sharing in order to save resources.

Real Time Control System for Metro Railways Using PLC & SCADA

This paper proposes to adopt SCADA and PLC technology for the improvement of the performance of real time signaling&train control systems in metro railways.The main concern of this paper is to minimize the failure in automated metro railways system operator and integrate the information coming from Operational Control Centre(OCC),traction SCADA system,traction power control,and power supply system.This work presents a simulated prototype of an automated metro train system operator that uses PLC and SCADA for the real time monitoring and control of the metro railway systems.Here,SCADA is used for the visualization of an automated process operation and then the whole opera-tion is regulated with the help of PLC.The PLC used in this process is OMRON(NX1P2-9024DT1)and OMRON’s Sysmac studio programming software is used for developing the ladder logic of PLC.The metro railways system has deployed infrastructure based on SCADA from the power supply system,and each station’s traction power control is connected to the OCC remotely which commands all of the stations and has the highest command priority.An alarm is triggered in the event of an emergency or system congestion.This proposed system overcomes the drawbacks of the current centralized automatic train control(CATC)system.This system provides prominent benefits like augmenting services which may enhance a network’s full load capacity and networkflexibility,which help in easy modification in the existing program at any time.

OPTIMAL TORQUE CONTROL STRATEGY FOR PARALLEL HYBRID ELECTRIC VEHICLE WITH AUTOMATIC MECHANICAL TRANSMISSION

In parallel hybrid electrical vehicle （PHEV） equipped with automatic mechanical transmission （AMT）, the driving smoothness and the clutch abrasion are the primary considerations for powertrain control during gearshift and clutch operation. To improve these performance indexes of PHEV, a coordinated control system is proposed through the analyzing of HEV powertrain dynamic characteristics. Using the method of minimum principle, the input torque of transmission is optimized to improve the driving smoothness of vehicle. Using the methods of fuzzy logic and fuzzy-PID, the engaging speed of clutch and the throttle opening of engine are manipulated to ensure the smoothness of clutch engagement and reduce the abrasion of clutch friction plates. The motor provides the difference between the required input torque of transmission and the torque transmitted through clutch plates. Results of simulation and experiments show that the proposed control strategy performs better than the contrastive control system, the smoothness of driving and the abrasion of clutch can be improved simultaneously.

THE DESIGN OF VMEBUS BRIDGE CONTROLLER WITH SHARC BUS

Targeting at the high expense and inflexibility to realize VMEbus bridge controller by professional Integrated Circuit (IC), this paper presents a scheme of adopting CPLD/FPGA (Complicated Programmable Logic Device/Field Programmable Gate Array) to design bridge controller between VMEbus and local bus. SHARC DSP (Digital Signal Processor) bus is an example. It has functions of nearly entire master/slave interface of VMEbus, and can act as DMA (Direct Memory Access) controller and perform block transfer in DMA or master processor initiative way without length limit. External circuit of the design is very simple. In comparison with special ICs, it has high performance to price ratio and can be easily applied to local buses of other processors with quite a little modification.

基于PLC反渗透海水淡化控制系统的设计与开发

针对反渗透海水淡化系统工艺复杂、运维繁琐、对操作人员专业技能要求高的特点,研发了一套反渗透海水淡化控制系统。详细研究整个工艺系统中预处理、反渗透等关键工艺环节的原理及自动控制过程。从系统的硬件设计和软件开发两个方面进行详细阐述。硬件设计方面,根据装置规模和控制需求完成控制系统设备选型。软件开发方面,完成控制器及人机交互界面多套软件的开发。该系统成功应用于高校反渗透海水淡化教学实践课。应用结果表明:该系统设计合理、操作界面简洁方便,在稳定安全运行的同时可实现教学培训、故障处理等目的。该系统在提高海水淡化操作人员专业技能的同时,也对高校创新其他专业的实操培训课程提供了借鉴和技术支撑。

基于5G多接入边缘计算的云化PLC系统架构设计与应用

随着工业控制系统对柔性化、扁平化的要求不断提升,以PLC为构建基础的传统工业控制网络在大规模接入、算力提升和部署灵活性方面均受到限制.针对这些问题,融合5G网络和边缘计算技术,设计了基于5G多接入边缘计算的云化PLC系统架构,阐述了该架构的运行机制和所涉及的关键技术;在此基础上,进行PLC系统的云化部署和调试,实现了工业现场、企业数据中心、5G网络和边缘网络的集成;最后,通过在某汽车制造公司产线改造过程中的应用,验证了所提架构的有效性.

规模化养鸡场鸡粪“两段式”好氧堆肥工艺研究

好氧堆肥是鸡粪资源化利用的重要途径,它不仅能够解决鸡粪污染问题,还能够产生有机肥用于土壤改良,增强土壤肥力。但在工程应用上,传统的槽式堆肥发酵周期长,而罐式堆肥又常因物料含水率过高而难以启动,发酵效果不甚理想。本研究设计了一种“两段式”好氧堆肥工艺,通过初级发酵槽(第一阶段)发酵降低了物料含水率,从而实现了物料在立式发酵罐(第二阶段)内的快速腐熟。应用该工艺的示范工程已完成建设并稳定运行,对发酵完成后的物料进行腐熟度评价,发现物料的pH、含水率、有机质、蛔虫卵死亡率、种子发芽指数等评价指标均已满足要求,可作为肥料使用。

新工科思维在实验课中的应用与实践--以“自动控制原理实验”课程为例

文章以“自动控制原理实验”课程为例,探讨了新工科思维在实验课程中的应用与实践。文章比较了传统教育和新工科思维的区别,强调了后者在跨学科技能、创新和实际应用中的重要性。文中介绍了将新工科思维融入实验课程的方法,并讨论了这种方法如何有效提升学生的问题解决能力、团队合作和创新能力。最后,文章对这种教育方法在适应社会发展需求方面的前景进行了展望。

基于PLC的滤站自动控制系统设计

针对滤站的污水处理流程,设计基于可编程逻辑控制器(Programmable Logic Controller,PLC)的滤站自动控制系统,并详细阐述该系统的硬件设计、软件设计。通过应用自动控制系统,滤站能够自动完成污水处理流程,缩短人工时间,提高工作效率。