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The intelligent warehousing control system is a system based on PLC (Programmable Logic Controller) and human-computer interaction (HCI), aiming to improve the efficiency and accuracy of warehousing operations. The system controls the operation and monitoring of storage equipment through PLC, and interacts with operators through human-computer. The system design includes equipment selection, PLC control system design, and human-computer design. In equipment selection, it is necessary to select equipment suitable for automation control to ensure that the system can meet the needs of warehousing operations. This paper introduces a programmable controller design method, that is, using soft and hard to achieve automatic control of memory. The hardware part is mainly composed of PLC, sensor, actuator and so on, which controls the operation of memory and monitors the relevant parameters. In the aspect of software, the related control program is designed by PLC programming language. The test results show that in the traditional warehouse system, the processing time of each commodity is more than 169 seconds; the utilization rate of warehouse is less than 70%, and the logistics operation time of the enterprise using PLC and HCI for intelligent storage control can be reduced to 57 seconds; on this basis, the data processing time of the system is reduced to 43 seconds, and the utilization rate of the warehouse is 93%. Therefore, this paper presents an intelligent warehouse control system based on PLC and man-machine interaction. The system can not only effectively improve the efficiency and accuracy of warehouse operation, but also enhance the safety and reliability of warehouse operation. It provides a reliable and flexible solution for automatic control and monitoring of warehouse. [ABSTRACT FROM AUTHOR]

With the increasing functionality of intelligent programmable controllers and the continuous improvement in power and component density, the problem of rapidly rising temperatures during operation has become increasingly prominent, directly affecting the controller's lifespan and stability[1]. Therefore, improving the heat dissipation efficiency of intelligent programmable controller modules has become a key focus of research. This paper introduces a method of installing aluminum alloy heat sinks on the core chip of the controller and carefully designing the fin shape and size of the heat sink to enhance heat conduction and heat convection effects, improving heat dissipation performance. This paper also constructs a thermal equivalent model of the controller and simulates the impact of different fin parameters on heat dissipation performance. Experimental results show that when the fin height is 5 millimeters, thickness is 2 millimeters, and spacing is 4 millimeters, the heat sink exhibits the highest thermal conductivity and the lowest thermal resistance, achieving optimal heat dissipation effectiveness. [ABSTRACT FROM AUTHOR]

The automation and control of industrial machines and processes is a task traditionally performed by PLCs and SCADA systems. However, with the advent of Industry 4.0 paradigm, which merges OT and IT domains, this task can also be performed inside the IT domain. This paper proposes an edge architecture where a flexible manufacturing line is led by a state machine programmed and running on the IT domain inside the Manufacturing Execution System. Each industrial asset has been modelled as a black-box, where security and hard real-time functionalities are programmed and controlled inside each black-box by traditional OT tools. Functionalities and variables required to synchronize each black-box, have been modelled as inputs and outputs. These input and output variables and methods are available using Industry 4.0 industrial communication protocols, such as OPC UA or MQTT. Then, a state machine programmed on a high-level IT language model inside the MES, automates the manufacturing line reacting to the inputs and outputs of each black-box. This architecture has been successfully validated automating a manufacturing line composed by a conveyor, a robot and a vision based quality control system. [ABSTRACT FROM AUTHOR]

Modern beekeeping uses various technological solutions to control and manage apiaries, but many need help with problems related to energy consumption and the inability to adapt to changing conditions. This article presents the development of the conceptual model of hardware-software complex architecture, focusing on the modularity and flexibility of the system. The main idea is to use a universal programmable logic controller with a modular architecture, which allows users to quickly adapt the system to new tasks by adding or replacing sensors and control mechanisms. The proposed approach considers minimizing energy consumption using energy-efficient LoRa technology for data transmission. Such a system's main advantages and potential risks are considered, and formulas for calculating energy consumption during data transmission are presented. The article can serve as a guide for specialists in the field of beekeeping and developers of automation systems. [ABSTRACT FROM AUTHOR]

Industry 4.0 has driven the need for Information Technology (IT) & Operational Technology (OT) convergence to modernize OT by leveraging IT. The challenges for manufacturing operations are utilizing and converting years of scattered data into valuable information integrated into the company's digital transformation strategy. This paper aims to provide a systematic literature review of current evidence in digital transformation for acquiring automation & control technologies data in manufacturing operations, such as Programmable Logic Controller (PLC), Supervisory Control and Data Acquisition (SCADA), Distributed Control System (DCS), and Manufacturing Execution System (MES), for analytics purposes and identify the current trends and best practices in this area. The findings cover current information on influential researchers, published journals, research trends, industries, industry types, types of analytics applications, methods, and frameworks for acquiring automation & control technologies data from the legacy OT infrastructure. [ABSTRACT FROM AUTHOR]

The production of hydrogen is still a major challenge, due to the high costs and often also environmental burdens it generates. It is possible to produce hydrogen in emission-free way: e.g. using a process of electrolysis powered by renewable energy. The paper presents the concept of a research, experimental stand for the storage of renewable energy in the form of hydrogen chemical energy with the measurement methodology. The research involves the use of proton exchange membrane electrolysis technology, which is characterized by high efficiency and flexibility of energy extraction for the process of electrolysis from renewable sources. The system consist of PV panel, PEM electrolyzer, battery, programmable logic controller system and optional a wind turbine. Preliminary experimental tests results have shown that the electrolyzer can produce in average 158.1 cc/min of hydrogen with the average efficiency 69.87%. • Zero-emission hydrogen production is possible. • Hydrogen production using a proton exchange membrane (PEM) electrolyzer for Polish conditions. • Proposal for experimental studies on hydrogen production. [ABSTRACT FROM AUTHOR]

In industrial hot-dip galvanizing lines, the crossbow flatness defect of steel strips constitutes one of the main sources for coating thickness deviations and inhomogeneities. In this work, a novel algorithm for online minimization of the crossbow flatness defect based on the automatic adjustment of the pot roll intermesh is developed. The devised model-free control algorithm can be easily implemented on an industrial programmable logic controller, even with very limited computational resources. The controller uses measurement data from an electromagnetic strip stabilization device and avoids the use of the delayed measurement data from the downstream radiometric coating thickness gauges. Assuming that a hot-dip galvanizing line is already equipped with an electromagnetic strip stabilization device, additional hardware is not required for implementation. The control algorithm can also be easily adapted to processing lines without an electromagnetic strip stabilizer. A detailed stability analysis allows to derive some basic guidelines to guarantee the convergence of the overall control scheme. A short- and long-term evaluation of measurement results from an industrial hot-dip galvanizing line demonstrates the effectiveness and robustness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Directed control is crucial for implementing controllers on programmable logic controllers. A directed controller is one that actively selects at most one controllable event (control command) to execute at any instant. This study investigates the numerical optimization problem of directed control for discrete-event systems, such as traffic systems and robotic systems. By integrating supervisory control theory and reinforcement learning, an algorithmic procedure is designed to synthesize an optimal directed controller, which minimizes the total cost associated with event execution while ensuring the safety and liveness of the controlled system. Two improved Q-learning algorithms incorporating dynamic parameter adaptation strategies are developed to enhance the global search ability of basic Q-learning. To demonstrate applicability and effectiveness, we apply the proposed method to control a guideway system and a multi-train traffic system, respectively. The experimental results indicate the superiority of the proposed method over the comparison methods. [ABSTRACT FROM AUTHOR]

Abnormal swing angle detection of bucket grabs is crucial for efficient harbor operations. In this study, we develop a practically convenient swing angle detection method for crane operation, requiring only a single standard surveillance camera at the fly-jib head, without the need for sophisticated sensors or markers on the payload. Specifically, our algorithm takes the video images from the camera as input. Next, a fine-tuned 'the fifth version of the You Only Look Once algorithm' (YOLOv5) model is used to automatically detect the position of the bucket grab on the image plane. Subsequently, a novel geometric model is constructed, which takes the pixel position of the bucket grab, the steel rope length provided by the Programmable Logic Controller (PLC) system, and the optical lens information of the camera into consideration. The key parameters of this geometric model are statistically estimated by a novel iterative algorithm. Once the key parameters are estimated, the algorithm can automatically detect swing angles from video streams. Being analytically simple, the computation of our algorithm is fast, as it takes about 0.01 s to process one single image generated by the surveillance camera. Therefore, we are able to obtain an accurate and fast estimation of the swing angle of an operating crane in real-time applications. Simulation studies are conducted to validate the model and algorithm. Real video examples from Qingdao Seaport under various weather conditions are analyzed to demonstrate its practical performance. [ABSTRACT FROM AUTHOR]

Petri nets (PNs) are typically used for design and verification rather than direct control implementation. In this paper, aligning with the Industry 4.0 paradigm's focus on flexible and reconfigurable control systems, we propose a modelling tool for rapidly prototyping feedback-based discrete-event control algorithms on programmable controllers such as PLCs or microcontroller boards. This modelling tool, named Signal Interpreted Coloured Petri Nets (SICPNs), aims to combine the formal modelling expressiveness of Coloured PNs with the capabilities of Signal Interpreted PNs, which are specialised in processing plant measurements and determining actuator commands. This contribution involves: (a) the formal definition of SICPN; (b) the presentation in the IEC61131-3 compliant SCL language of the so-called Token Player , a software entity designed to support feedback-based decision-making within the SICPN; (c) the validation of the effectiveness of the proposed formalism in controlling an extended configuration of the FESTO Modular Processing Station (MPS) using an Arduino microcontroller via two-way UART serial communications; (d) the modelling of a Digital Twin of the FESTO MPS testbed. The tests demonstrate that, during transitions, the colour and signal interpretation conditions enable the microcontroller to accurately schedule and dynamically reconfigure control actions while keeping the size of the PN-based controller small relative to the control problem's complexity. • The formal definition of Signal-Interpreted Coloured Petri Nets. • A new Petri Net model that merges colouring and signal interpretation features. • Token Player designed to support feedback-based decision-making within the SICPN. • Digital Twin of an extended configuration of the FESTO Station using an Arduino. • Modelling of the Digital Twin of the FESTO Modular Processing Station testbed. [ABSTRACT FROM AUTHOR]

• Proving efficacy of no-code systems in labs. • Utilizing cobot and PLC in sample processing. • Developing open-source hardware for automation. • Addressing challenges in handling HPTLC plates. • Demonstrating integration of automated lab stations. Driven by demographic changes and dwindling Science Technology Engineering Mathematics enrolments, our research introduces no-code automation as a strategic response, aimed at mitigating labor shortages while enhancing productivity and safety in the laboratory environment. Employing a user-friendly, no-code software platform, we automated a complex HPTLC assay, enabling laboratory personnel to configure and modify workflows without requiring specialized programming skills. The manuscript outlines the deployment of a collaborative robot (cobot), a programmable logic controller (PLC), and the utilization of self-developed open-source hardware components to establish automated stations for sample handling, incubation, spraying, detection, and storage within the assay process. The research addresses challenges such as the handling of fragile HPTLC plates and the seamless integration of automated stations, solved through innovative design solutions and adaptive programming methods. This investigation demonstrates the feasibility and efficiency of no-code automation in overcoming skilled labor deficits. [ABSTRACT FROM AUTHOR]

• This paper adopts a unified algorithm to handle disturbances at different locations, which has a wider adaptability. • This paper only requires that the disturbance is bounded, which broadens the premise and has good practical engineering application ability. • This paper accelerates the convergence speed of the system after disturbance and improves the dynamic performance of the system. The large-scale application of measurement devices, programmable controllers, and power electronic devices increases the likelihood of distributed energy storage systems suffering from various disturbances, thus affecting the stable operation of the system. In this paper, an adaptive finite time fast resilient control strategy is proposed for the unknown transmission disturbance in the control channel of distributed energy storage system. Firstly, the adverse effects of sensor and actuator disturbances on conventional consensus-based secondary control strategies are quantitatively analyzed. Secondly, an resilient control protocol with adaptive compensation mechanism based on terminal sliding mode is proposed, and the suppression mechanism of the controller to the unknown disturbance of the sensor and the actuator is analyzed, and the finite time convergence of the proposed distributed resilient secondary control strategy is proved theoretically. Experimental results show that the proposed control strategy is correct and effective. [ABSTRACT FROM AUTHOR]

• A novel impact fatigue device based on the split Hopkinson pressure bar. • A novel method to achieve repeated impact loading with constant amplitude. • The method has the advantages of controlling loading waveform and monitoring load. • The loading rate has a significant effect on the fatigue life of Ti-6Al-4 V. The lack of reliable testing methods and standards hinders systematic research on the impact fatigue performance of materials. The aim of developing an impact fatigue test method is to generate repeated impact loads with a constant amplitude, which is difficult to achieve using various existing impact test devices. This study investigated the principles of cyclic loading-resetting and constant-amplitude loading based on the split Hopkinson pressure bar (SHPB) system, established a novel impact fatigue test device, and verified the developed method by testing the impact fatigue life of a Ti-6Al-4V alloy. Electromagnetic valves, laser sensors, and a vacuum pump were used in the developed device to launch and reset the striker bar; a servo motor and laser sensors were used to reset the loading bars and specimen, and the entire system was controlled by a programmable controller to achieve continuously repeated loading. To achieve constant-amplitude loading, the conditions required to ensure that the specimen moves away from the incident bar before the returning stress wave reloads the specimen was derived. It was found that a constant-amplitude repeated impact on the specimen could only be achieved through the precise design of the geometric configuration and material of the loading bars. This method is considerably simpler than various existing methods based on energy absorption and is more applicable to impact fatigue tests. The verification tests showed that the highest loading frequency of the device was 0.5 Hz, the loading rate exceeded 105 kN/s, and the amplitude error of the repeated impact loads did not exceed 2.45 %. Under loads with the same amplitude, the impact fatigue life of a Ti-6Al-4V alloy was considerably shorter than the non-impact (low strain rate) fatigue life, which indicates the necessity of investigating the strain rate effect on the fatigue performance of materials. [ABSTRACT FROM AUTHOR]

The present article introduces an adaptive filter of statistical basis developed for closed-loop control applications, whose goal is to reduce actuator wear while ensuring a similar control performance regarding the original closed-loop system. The main idea is to avoid the rapid change of the filtered signal when the system output has a derivative not statistically significant regarding the expected measurement noise. The adaptation law of the time constant of the filter is model-free, and the only required information is the variance of the additive noise that the measurements are subjected to. The performance of the proposed adaptive method is illustrated through a combined numerical and experimental study, in addition to its application in an operational oil plant. The results indicate that our formulation holds promise for extending the life of actuators and is easy to implement in most programmable logic controllers. • A novel concept of statistical-based filter for control loops. • Negligible impact on system performance while significantly reducing actuator usage. • Model-free and easy-to-use solution for large-scale implementation. • Required design parameter is only the variance of measurement device. • Validated in an experimental apparatus and implemented in an industrial oil plant. [ABSTRACT FROM AUTHOR]

Cyber Physical Systems (CPSs) are considered as an integration of computing, networking, and physical processes. In such systems physical processes are monitored and controlled by the combination of computation, communication, and control technologies. Examples of CPSs include process control systems, medical devices, robots, and critical infrastructures such as water treatment plants, water distribution systems, and power grid. Often, these systems are vulnerable to attacks as the cyber components such as Supervisory Control and Data Acquisition (SCADA) workstations, Human Machine Interface (HMI), and Programmable Logic Controllers (PLCs) are potential targets for attackers. Replay attacks are easy to perform on such systems and can potentially lead to significant damages to the system. Therefore, timely detection of replay attacks is important to mitigate the attack consequences. In this work, we propose a practical watermarking technique to detect the attacks. Experiments are performed on a real WAter DIstribution system (WADI) to explore how to tackle the replay attacks using watermarking signal. • How do we tackle the replay attack using the physical watermark signal. • The challenges faced around the design of a practical watermark technique. • Testing of the proposed technique on a live water distribution system. [ABSTRACT FROM AUTHOR]

In a directly-coupled photovoltaic-powered membrane desalination (PV-membrane) system, the solar power supply must exceed a certain threshold for the pump to generate sufficient hydraulic pressure to overcome the membrane's osmotic barrier. Below this threshold, no appreciable membrane flux is produced, meaning PV power is underutilised or dissipated by the system. In this work, a power control management system (PCMS) is designed to harvest the underutilised PV power into a supercapacitor (SC) to, firstly, buffer the periods of solar irradiance fluctuations during daily operation. Secondly, this also fosters a continuous stable operation of the PV-membrane system across multiple solar days. The investigation compared the performance of the PCMS against two other configurations: "directly-coupled" (passive, no SC) and "semi-active" (with SC, but no PCMS). During a three-day test desalinating brackish water (5 g/L salinity), the PCMS enabled an improvement in water quality, with the permeate electrical conductivity (EC) 46% and 23% lower than the other configurations, respectively. The specific energy consumption (SEC) was reduced by 18% and 6%, respectively, during the same period. During a week-long experiment, the PCMS facilitated the production of 6218 L of potable water at an average EC of 0.52 mS/cm, while maintaining a minimum state-of-charge of the SCs to about 40%, allowing for subsequent use. The system also achieved a maximum load-matching efficiency of 99.6%, surpassing the 94.7%–96.6% observed in the other configurations. These results pave the way for maximising daily PV energy utilisation, ensuring steady and dependable clean water production for the community and improving the water-energy nexus. [Display omitted] • Optimise daily energy use of photovoltaic-powered membrane desalination system • Control algorithms: Directly-coupled & Semi-active, with & w/o supercapacitors (SC) • ∼1000 L per day produced during 3–7 day tests performed under different solar days • Control system with SC afforded: 1) 6–18% lower specific energy consumption (SEC); • 2) 42–83% improved water quality; 3) the highest (99.6%) load-matching efficiency [ABSTRACT FROM AUTHOR]

Nuclear power plant (NPP) cybersecurity research often relies on hardware-in-the-loop (HIL) testbeds that integrate real hardware components into simulated environments. These testbeds allow researchers to identify vulnerabilities, evaluate attack impacts, and test security measures in a controlled setting. However, previous HIL testbeds lacked fidelity to accurately represent real nuclear systems, limiting the scope of cybersecurity analysis. This study presents the creation of a HIL testbed, devised upon a full-scope, high-fidelity NPP simulator, to facilitate realistic and comprehensive cybersecurity research. To demonstrate its capabilities, the control logic for the steam generator water level was migrated from the simulator to an external programmable logic controller. As a practical application of the developed testbed, supply chain attack scenarios were simulated by injecting malicious code into the controller logic, and the effects of manipulating sensor inputs and control commands were observed. While this HIL testbed provides more detailed simulations, enhanced realism, and wider applicability compared to other options utilizing a less complex simulator, it is also more intricate and costly. For this reason, we include a detailed comparison with some alternative architectures to aid fellow researchers and practitioners in the selection of a suitable HIL architecture based on specific research objectives. • A HIL testbed with a high-fidelity simulator for cybersecurity research was built. • The HIL testbed simulates plant behavior and enables PLC control logic cyber-attacks. • A comparative analysis of HIL architectures is presented to guide design choice. [ABSTRACT FROM AUTHOR]

• The safety and interlock protection system constitute integral components of HHFTF's overall control system, providing the capability to manage various subsystems, many of these systems are operated reliably close to their performance limits in order to achieve the desired goals. • Demonstration of an enhanced interlock protection system, encompassing both software and critical hardwired interlocks, within the high heat flux test facility. • Three different types of architecture have been developed: (1) Slow Architecture based on PLCs, for functions where response time of longer than 20 ms is adequate; (2) Fast Architecture based on FPGAs, for functions requiring fast response time beyond the capabilities of the PLC; and (3) Hardwired Architecture for critical functions. • Activation times of interlocks are demonstrated within a range from 100 microseconds to 116 milliseconds. This paper introduces the safety and protection measures implemented in the High Heat Flux Test Facility (HHFTF). The interlock system has been enhanced and integrated into HHFTF to ensure the protection of the facility and the safety of personnel, thereby mitigating risks during operations. The primary purpose of these interlocks is to secure the entire facility under well-defined conditions to prevent accidents. The safety and interlock protection system constitute integral components of HHFTF's overall control system, providing the capability to manage various subsystems, many of these systems are operated reliably close to their performance limits in order to achieve the desired goals. The overall safety, interlock protection and the control system encompasses both hardware components and software, employing Programmable Logic Controllers (PLCs) and Field Programmable Gate Arrays (FPGAs), along with wired logic based on relays and special logic cards. Three different types of architecture have been developed: (1) Slow Architecture based on PLCs, for functions where response time of longer than 20 ms is adequate; (2) Fast Architecture based on FPGAs, for functions requiring fast response time beyond the capabilities of the PLC; and (3) Hardwired Architecture for critical functions. The paper showcases the successful testing and outcomes of an enhanced interlock protection system, encompassing both software and critical hardwired interlocks, within the HHFTF. Key parameters monitored include the maximum allowable job threshold temperature, flow rates (for coolant loss detection), and chamber pressure. Activation times of interlocks were observed within a range from 100 microseconds to 116 milliseconds. [ABSTRACT FROM AUTHOR]

Under the promotion of sustainable development goals, cleaner production (CP) has become an important strategy for energy-intensive manufacturing industries to maintain their competitiveness. Studies have shown that the implementation of Industry 4.0 (I4.0) can effectively promote the CP process in manufacturing. However, existing studies often focus on specific scenarios, limiting a comprehensive assessment of the industry's overall status. This paper aims to provide a comprehensive overview of the main research areas of I4.0 and its key impacts on CP by employing systematic mapping studies. By reviewing 121 studies retrieved from the Web of Science, a hierarchical analysis framework centered on the product life cycle (PLC) has been introduced. This framework provides a holistic analysis of sustainable intelligent manufacturing, summarizing the application of I4.0 and its impact on CP across the PLC stages. The main findings reveal a growing focus on I4.0 and CP, with the manufacturing and maintenance stages of the PLC being primary research scenarios. Moreover, attention should be directed towards integrating clean technologies, bolstering industrial data security, fostering circular economy practices, and exploring emerging fields like Industry 5.0. Moreover, to better explain the impact of this study, management implications are also provided from the three dimensions of theory, practice, and policy. These viewpoints and conclusions are of great significance for guiding future research and practical applications. • A comprehensive review of Industry 4.0 and cleaner production is conducted. • Systematic mapping and bibliometric methods are employed. • A hierarchical framework based on product life cycle is proposed. • The current challenges and future prospects are discussed. • Management implications from theory, practice, and policy are provided. [ABSTRACT FROM AUTHOR]

In this study, a continuously anaerobic two-stage pilot plant was established for bioenergy production, comprising 5 major pieces of equipment: a mixing tank, 1st anaerobic digester (AD), 2nd AD, sediment tank, aeration tank, and final sediment tank, all operating at ambient conditions. The operation of the continuously anaerobic two-stage pilot plant was automatically controlled by a programmable logic controller (PLC) using a designed control logic concept to set the hydraulic retention time (HRT) and inlet substrate concentration. The organic loading rate, pretreatment of hydrolysis pressure, and microbial community analysis were investigated for their effects on biogas production performance using different substrates: soybean residue (SR) and food waste hydrolysate (FWH), respectively. It was found that the peaks of biogas production rate on daily volumetric feeding were 1.20 m³·m⁻³·d⁻1, and the biogas yield on VS added was 760 dm³·kg⁻1 from food waste hydrolysate with a pretreatment hydrolysis pressure of 10 kg cm⁻2, at an OLR in COD concentration of 3.56 kg m⁻³·d⁻1, and an HRT of 11 days, respectively. The Methanobrevibacter genus was found to be abundant in the 1st AD, approximately 6.7 times more abundant than in the 2nd AD. The continuous anaerobic two-stage pilot plant was properly examined for its application in treating food waste and soybean residue with the goal of obtaining renewable bioenergy. [Display omitted] • Analyzing the biogas production performance from soybean residue and FW hydrolysate. • The daily biogas production rate increased with organic loading rate increasing. • Abundance of the Methanobrevibacter genus relatively higher in 1st AD than 2nd AD. • Resulting a biogas production possibility from FWH at high substrate concentration. [ABSTRACT FROM AUTHOR]

Design of digital control systems is often based on use of Programmable Logic Controllers (PLC). Such devices offer a broad variety of functions that can be organized in blocks independently or in hierarchical structures. Such an organization can lead to cumulative delays in reaction time of digital outputs of the control system. In the paper there are described results of research aimed to determine dependencies of various aspects of designing programs for Programmable Logic Control devices influencing the effective time of reaction of digital outputs. Research method is presented, assumptions are made, and experiments are described and discussed. Observations of system behavior are presented for selected control tasks and different control situations. Research results are presented and discussed, conclusion is drawn, and areas of future work are identified. [ABSTRACT FROM AUTHOR]

The conventional CMOS scaling trend faces device scaling limitations, interconnect bottleneck, and signal integrity issues due to crosstalk, which is the unwanted interference of signals between neighboring metal lines. Traditional computing circuits always try to reduce the crosstalk noise by applying various circuit and layout techniques. In contrast, Crosstalk computing is a new computing framework that can leverage this detrimental effect and convert it astutely to a useful feature. The Crosstalk is engineered into a logic computation principle by leveraging deterministic signal interference for innovative circuit implementation. In this paper, we present a comprehensive circuit framework for Crosstalk Computing and derives all the key circuit elements that can enable this computing model for large-scale design. It also performs a comparison study between Crosstalk circuits and existing CMOS-based approaches. The ability to design a wide range of logic circuits (basic and complex logics) and programmable gates compact in design and minimal in transistor count is unique to Crosstalk Computing, which leads to benefits in the circuit density, power, and performance. The circuit simulation results designed at 7 nm show 3.4x improvement density, 62% reduction in Energy-Delay-Product (EDP), and 34.5% improvement in performance compared to counterpart implementation in CMOS circuit style. • Interference based radically new concept to compute logic for digital Integrated Circuits. • Fabricated a proof-of-concept prototype Chip for Crosstalk Computing at TSMC 65 nm technology. • A detailed methodology for large scale circuit implementation and discussed signal integrity aspects of Crosstalk Computing. • Presented a host of circuit styles for quick adaptation of Crosstalk Computing. • A unique hardware-level programmability feature allowing run-time reconfiguration and enabling security, and fault resilience. [ABSTRACT FROM AUTHOR]

Existing monitoring and control of an induction motor systems must be interoperable with next generation products to ensure smart integration in order to update existing system by reducing the cost and increasing the reliability. The best method must be chosen for efficient use of energy in some cases such as speed control, switching-on or switching-off, or in controlling the speed of induction motors, which make up a large part of the load group in industrial field. In this study, the controlling and monitoring of an induction motor parameters were carried out over a computer by using the Profibus (Process Field Bus) communication method through the TIA (Totally Integrated Automation) Portal program used to program all Siemens PLCs (Programmable Logic Controllers). The induction motor parameters were obtained over the frequency converter without using additional cards such as current, voltage, frequency and speed measurement. In this way, cables and electronic cards confusion were avoided and a safer, faster and more functional application was implemented compared to classical methods. KEPServerEx OPC (Ole-for Processing Control) Server program by OPC Foundation was preferred for the communication of computer with a PLC. Profi-Lab editor program was used for monitoring and controlling the system over a computer. • Monitoring and controlling of the electrical parameters of an induction motor. • The SCADA based automation and hardware configuration in TIA portal platform. • Profibus communication feature and the system with ProfiNET communication. • Remote control of the induction motor with frequency converter. • Technical characteristics of Profibus-DP communication. [ABSTRACT FROM AUTHOR]

A fully-submerged bottom-standing 1.5 MW wave energy converter (WEC) equipped with a membrane-pump system is under development for installation at a test site off the coast of Pembrokeshire, Wales, UK. The system comprises several flexible-membrane air cells that are compressed and sucked by the action of the waves, rectifying valves, low-pressure and high-pressure ducts, and a unidirectional air turbine that drives an electrical generator. This two-part paper reports the design and testing of an effective control law to be implemented into the programmable logic controller of the membrane-pump turbine-generator set, allowing efficient and safe operation for the wave climate at the Pembrokeshire test site. Part 1 of this paper concerns developing the design strategy of the control laws, the numerical model, and the performance evaluation of the WEC power take-off system. A genetic algorithm is used to design control laws to maximise each sea state's WEC time-average efficiency. An adaptive control algorithm is devised by cross-correlating the control laws parameters and the rotational speed. The final result is a control law that uses input the rotational speed signal and airflow density. It adapts to the sea state conditions while maximising the time-average total efficiency of the membrane-pump WEC for deployment off the Pembrokeshire coast. • A genetic algorithm used to design control laws. • Torque versus rotational speed control-laws studied using Bézier curves. • Adaptive control devised by correlating control parameters and rotational speed. • The control law uses as input the rotational speed and airflow density. • A one-parameter adaptive control law provides good performance. [ABSTRACT FROM AUTHOR]

Predictive PI (PPI) controllers have demonstrated to exceed traditional PID controllers when they are applied to systems with long delays. This work proposes a new controller structure and tuning that we call Generalized Predictive PI (GPPI) controller which provides greater design flexibility than PI and PPI strategies. To realize a fair comparison, the design and tuning rules for discrete PI and PPI controllers were developed using optimal arguments based on the root-locus, for critically damped response before a step change in the reference. Experimental results, using industrial equipment, have illustrated the tuning methodology and the performance of the proposed controller under real conditions. Flow and water level process in a laboratory flume were considered. For these processes, First Order Plus Time Delay (FOPTD) models are used. The GPPI control results are encouraging, reducing the settling time plus a very small overshoot before step change in the reference regarding the PI and PPI strategies, up to 41.03% for the flow control loop and up to 54.21% for the level control loop. The discrete analysis of the strategies in the Z plane was performed, allowing for a direct translation to recursive equations that can then be programmed into a Programmable Logic Controller (PLC), other industrial controllers such as Distributed Control Systems (DSC), or microcontrollers, such as Arduino, Raspberry or FPGA. This is an important result, since it demonstrates that the increased complexity of the proposed controller does not hamper its implementation in industrial controller systems. In this work, we used a Rockwell ControlLogix \protect \relax \special {t4ht=®} PLC with Structured Text programming language. • Systems with long time delays are particularly challenging for a PID controller. • The Predictive PI controller has been previously proposed as a PID alternative. • The Generalized PPI controller proposed here extends on the PPI controller.. • The Generalized PPI controller offers more performance design freedom. • The Generalized PPI controller introduces a limited increase in complexity. • Experimental verification shows superior performance of the GPPI controller. [ABSTRACT FROM AUTHOR]

This paper presents an approach to automatically amend an erroneous model of an implementation using a safety specification as the basis to ensure safety. Industrially, safety PLCs are common to ensure safe operations. However, before its commissioning, the implemented safety code must be tested for faults caused by spurious transitions and missing safety transitions. Spurious transitions are implemented events that are not prescribed by the safety specification, while missing safety transitions are unimplemented safety events that are prescribed by the safety specification. The presence of these faults can result in material or human damage. The proposed approach requires the model of an implementation to be trace equivalent with the given safety specification only in terms of traces composed of safety events, which is captured by the notion of safe-IOCOS. If the implementation emits other than the specified safety events then the implementation is not safe-IOCOS and requires amendment. This is achieved by removing the spurious transitions and adding the missing safety events in the implementation using synthesis techniques from the supervisory control theory. The infimal controllable superlanguage is used to compute the infimal safety extension , which adds the missing safety transitions. It is shown how the resulting model of an implementation after amendment is both safe-IOCOS and controllable with respect to the specification. [ABSTRACT FROM AUTHOR]

In this paper, a novel approach for fault tolerant control of large-scale manufacturing systems is presented. A specification governor is introduced, which is inspired by the concept of "reference governor" in feedback control systems. The goal is to modify an infeasible sequence of specifications, which can be used to generate a distributed logic controller, in such a way that the desired product requirements are satisfied in case of faults. The procedure considers redundancies in the manufacturing system and has the capability of keeping the modification of the infeasible specification sequence as less as possible. A modeling process is proposed that automatically adapts fault-free models in form of signal interpreted Petri nets (SIPNs) according to the occurring faults. Based on these faulty models, it is possible to find out which of the natural language specifications in the specification sequence cannot be executed. [ABSTRACT FROM AUTHOR]

• Timed process calculi for expressing both genuine and malicious activities within a PLC. • Runtime enforcement based on Ligatti et al.'s edit automata. • Algorithms to synthesise edit automata from PLC specifications. • Simulation and bisimulation proof techniques. • Simulations of a significant use case in Simulink/Matlab. We define a simple process calculus, based on Hennessy and Regan's Timed Process Language , for specifying networks of communicating programmable logic controllers (PLCs) enriched with monitors enforcing specification compliance at runtime. We define a synthesis algorithm that given an uncorrupted PLC returns a monitor that enforces the correctness of the PLC, even when injected with malware that may forge/drop actuator commands and inter-controller communications. Then, we strengthen the capabilities of our monitors by allowing the insertion of actions to mitigate malware activities. This gives us deadlock-freedom monitoring : malware may not drag monitored controllers into deadlock states. Our enforcing monitors represent a formal mechanism for prompt detection of malicious activities within PLCs. Finally, we illustrate our results by implementing in Simulink a non-trivial Water Transmission Network (WTN) system, and testing the effectiveness of our monitors in detecting and mitigating three different attacks targeting the PLCs of our WTN. [ABSTRACT FROM AUTHOR]

The existing Programmable Logic Controller (PLC) based on microprocessors (μ p) or micro-controllers (μ c) are commonly used in the industry for various instrumentation and control applications. PLC exhibits limitations such as less flexibility, poor scanning time, slower speed, and degraded response for high-speed industrial applications due to its fixed hardware and serial execution mechanism. A new Field Programmable Gate Array (FPGA) based PLC multi-channel High Speed Counter (HSC) module has been proposed, enhancing performance and flexibility compared to the existing PLC-HSC module. The proposed FPGA-PLC-HSC module has a 2-phase 2-Input counter with resolutions of 1X, 2X, and 4X which improve performance in terms of accuracy for position speed, and direction measurement applications. The FPGA-PLC-HSC module is implemented with the feedback node method and the shift register method inside LabVIEW FPGA along with device utilization. The simulation results show that the FPGA-PLC-HSC module has faster scanning time, good linearity, better resolution, maximum supporting input frequency, and counting frequency. For experimental purposes, an optical encoder M110960 (E8P-512-118-S-D-M-B) with a signal conditioning circuit is connected to the NI-myRIO-1900 FPGA platform. The experimental results point out that the proposed FPGA-PLC-HSC module offers faster scanning time, better accuracy and linearity in 1X, 2X, and 4X resolution. [Display omitted] • FPGA-PLC-HSC module is proposed with high resolution, linearity, and flexibility. • It is used to enhance performance for speed, position, and direction measurement applications. • The reported accuracy is ± 0.2675%, ± 0.1689%, and ± 0.12% in 1X, 2X and 4X resolution, respectively. • Proposed module offers less scantime, fast speed, and cost-effectiveness solution. [ABSTRACT FROM AUTHOR]

In the production of paper cups in industrial factories, it is tried to print high quality cups with less waste loss with the help of sensors and heating resistances mounted on the paper cup machine. In this study, a system that detects faulty products based on image processing and removes it by controlling the machine with servo motors, asynchronous motors and programmable logic controller (PLC) is designed. For fault product detection, classification has been performed using real-time Haarcascade algorithm and You Only Look Once (YOLO) algorithm which is a deep learning methods, and real-time object detection has been carried out using the OpenCv library. With this study, an effective faulty product detection and removing hardware system was realized by adapting artificial intelligence algorithms to a machine used in industry. Based on the results, a whole system can be applied to systems that involve removing a faulty product from a band in any production, packaging etc. facility is proposed. A hardware consisting of servo motors, asynchronous motors and PLC was designed to separate faulty cups from the existing paper cup production machine in this study. Then, a data set composed of 1068 images was created with images taken from the camera for faulty and faultless paper cups. Using this dataset, the effect of different deep learning methods on performance in the real-time system has been examined and successful results have been obtained. The optimal outcome was achieved, yielding a real-time application accuracy rate of 90.8% through the utilization of the Yolov5x architecture. [ABSTRACT FROM AUTHOR]

Industrial Internet of Things (IIoT) is a product of deep integration between Internet of Things (IoT) and industrial control networks. As an important component of IIoT, Programmable Logic Controller (PLC) has become a springboard for many hackers to disrupt industrial networks by spreading viruses. It is known that worm can cause enormous loss. Therefore, revealing the rules of worm spread in PLC networks and exploring methods to inhibit worm spread are increasingly important. To this end, we propose a new worm spread model named SIHQR with time delay. Additionally, we establish a game model between susceptible and infected nodes in order to express the infection rate by several game parameters. Through analysis, we discuss the conditions for the emergence of three scenarios: disease-free equilibrium, endemic equilibrium and Hopf bifurcation. We study the stability at the equilibrium points and obtain an expression for a threshold value which determines whether the system exhibits endemic equilibrium or Hopf bifurcation. In the experimental section, we analyze the impact of initial values of node states and the magnitude of game parameters on worm spread in the three aforementioned scenarios. Finally, we propose a method to mitigate or even eliminate the Hopf bifurcation. The experimental results show that the proposed model has welldone performance. [ABSTRACT FROM AUTHOR]

A fully-submerged bottom-standing 1.5 MW wave energy converter (WEC) equipped with a membrane-pump system is being developed for installation at a test site off the coast of Pembrokeshire, Wales, UK. The system comprises several flexible-membrane air-cells that are compressed and sucked by the action of the waves, a system of rectifying valves, low-pressure and high-pressure ducts and a unidirectional air turbine that drives an electrical generator. This two-part paper reports the design and testing of an effective control law to be implemented into the programmable logic controller of the membrane-pump turbine-generator set, allowing efficient and safe operation for the wave climate at the Pembrokeshire test-site. Part 2 of this paper focuses on the experimental investigation at the IST variable flow test rig of the real-time control algorithm described in Part 1 of this paper, using a 1:2.4 turbine scale model. Tests were performed for five sea-states and two turbine model average rotational speeds. Experimental results reveal that the control law proposed for the Pembrokeshire mWave turbine-generator set, based only on the turbine rotational speed and airflow density measurements, is effective and of a simple implementation. Fine fitting between the model testing results validates the performed scaling of the variables related to the time-dependent turbine-generator operation, as well as the numerical model of the system described in Part 1. • The turbine-generator set real-time control algorithm was experimentally studied. • Tests were performed for five sea-states and two turbine model average rotational speeds. • The control law based on the turbine rotational speed and airflow density is effective. • Model testing results validate the scaling of the turbine-generator operation time-dependent variables. [ABSTRACT FROM AUTHOR]

Dielectric elastomer actuators (DEAs) are an emerging type of soft actuator that show many advantages including large actuation strains, high energy density and high theoretical efficiency. Due to the inherent elasticity, such actuators can also be used as soft oscillators and, when at resonance, the dielectric elastomer oscillators (DEOs) can exhibit a peak oscillation amplitude and power output with an improved energy efficiency in comparison to non-resonant behaviour. However, most existing DEOs have a fixed pre-defined morphology and demonstrate a single stable equilibrium, which limits their versatility. In this work, a conical DEO is proposed which may exhibit either monostability (i.e. one stable equilibrium point) or bistability (two equilibria). The system demonstrates a transition between two regimes using a voltage control. Such a feature allows the DEO system to have multiple oscillation modes with different equilibrium points and the transition between equilibria is controlled by an effective control strategy proposed in this work. A mathematical model based on the Euler-Lagrange method is developed to investigate the stability of this system and its complex nonlinear dynamic response in unforced and parametrically forced cases. This design has potential in more advanced and versatile DEO applications such as active vibrational controllers/ shakers, active morphing structures, smart energy harvesting and highly programmable robotic locomotion. [ABSTRACT FROM AUTHOR]

Design of the collector in solar air collector dryer (SACD) system is very important factor for high drying performance and the effective use of solar radiation. The main purpose of this study is to increase the thermal efficiency of the solar air collector (SAC) by adding a two-direction solar tracking feature supported by programmable logic controller (PLC) to the SAC. A movable SAC and fixed SAC with same dimensions were designed and integrating both collectors into the drying cabinet, generating two different SACDs. Semielliptical sliced products were dried at similar air flow rate and ambient conditions in both drying systems. The results indicated the highest SAC thermal efficiency was 91% in the SACD with solar tracking feature, while the lowest SAC thermal efficiency was 34% in the other SACD. In addition, the drying process in the solar tracking feature SACD was performed with an average drying efficiency of 66%, while the fixed SACD was performed with an average drying efficiency of 32%. Based on the results, the main role of PLC solar tracking feature in SACD system is to increase the average thermal efficiency by 42% and to double the average drying efficiency. • High thermal efficiency solar air collector (SAC) design. • The SAC with 2-way sun tracking feature thanks to the programmable logic control solar tracking system. • Integration of the fixed and the movable SAC produced in the same dimensions to the drying cabinet. • The movable SAC has 42% more thermal efficiency and 50% more drying efficiency. [ABSTRACT FROM AUTHOR]

How to establish an effective electrical automation control water treatment system, optimize the operation effect, reduce cost investment, of great significance. The design of an electric automatic control water treatment system based on LabVIEW is proposed. Siemens industrial computer is used as the upper computer, and the S7-300 series of Siemens is used in a programmable logic controller (PLC) system. Based on the LabVIEW development platform, the OPC server is set up by Siemens SIMATIC. NET, which can connect with PLC to realize real-time communication. SQL Server is used as a backstage database to realize basic monitoring functions such as data collection, equipment control, real-time curve display, history record, fault alarm, etc. The experimental results show that the system can predict the biological oxygen demand concentration online and compare it with the measured value. It can adjust the control strategy in time, reduce the fault, save the dosage and reach the goal of economical operation. [ABSTRACT FROM AUTHOR]

Smart manufacturing systems are an attractive target for cyber attacks, because they embed valuable data and critical equipment. Despite the market is driving towards integrated and interconnected factories, current smart manufacturing systems are still designed under the assumption that they will stay isolated from the corporate network and the outside world. This choice may result in an internal architecture with insufficient network and system compartmentalization. As a result, once an attacker has gained access, they have full control of the entire production plant because of the lack of network segmentation. With the goal of raising cybersecurity awareness, in this paper we describe a practical case study showing attack scenarios that we have validated on a real modular smart manufacturing system, and suggest practical security counter measures. The testbed smart manufacturing system is part of the Industry 4.0 research laboratory hosted by Politecnico di Milano, and comprises seven assembly stations, each with their programmable logic controllers and human-computer interfaces, as well as an industrial robotic arm that performs pick-and-place tasks. On this testbed we show two indirect attacks to gain initial access, even under the best-case scenario of a system not directly connected to any public network. We conclude by showing two post-exploitation scenarios that an adversary can use to cause physical impact on the production, or keep persistent access to the plant. We are unaware of a similar security analysis performed within the premises of a research facility, following a scientific methodology, so we believe that this work can represent a good first step to inspire follow up research on the many verticals that we touch. [ABSTRACT FROM AUTHOR]

Digital Twin (DT) represents the next wave in modelling, simulation and optimization technology. A key enabling technology of the DT is the real-time coupling of the digital models with the controllers of the physical plant. To implement the DT through real-time coupling, common approaches and vocabularies are desirable for the automation software to facilitate the exchange of information between the PLCs and the digital models. However, the scarce adoption of guidelines and standards within the industrial practice of PLC programming complicates this context. To face this challenge, this paper proposes a methodology for PLC code to standardize the vocabulary and the management of the operational modes of industrial automation systems. The methodology consists of a GEMMA-GRAFCET representation and a Hierarchical Design Pattern. By implementing the approach to a case study, it is demonstrated that the methodology generates a standard interface for the communication between PLCs and digital models within a DT architecture. [ABSTRACT FROM AUTHOR]

Energy efficiency has emerged as one of the most essential design parameters in contemporary computing system design. Approximate computing is a new computing paradigm to achieve energy efficiency by trading-off energy/area/latency improvements with accuracy for error-resilient applications. This paper proposes R econfigurable E nergy-efficient A pproximate D ivider (READ) that achieves several energy–quality configurable modes using fixed restoring array divider architecture. Conventional approximate binary dividers require various divider hardware configurations to achieve distinct energy–quality trade-off points, which decreases the hardware flexibility, especially for modern embedded systems. READ accomplishes energy efficiency while meeting the dynamically varying accuracy requirements of the targeted application. READ uses reconfigurable subtractor cells that can work in either accurate or approximate mode using a subtractor cell controller logic. The paper also introduces the design of overflow detector using minimal hardware resources. A comprehensive accuracy and hardware evaluation on CMOS 45-nm technology node are performed for the proposed dividers as well as other state-of-the- art divider designs. Compared to the accurate 16 ∕ 8 divider design, the proposed divider shows an improvement of 49% in terms of energy efficiency and is 1.26x faster, while introducing minimal errors. The proposed divider design is demonstrated for its efficacy in image processing tasks and shows nominal effect on the output quality. • A fixed restoring array based approximate divider is proposed and presented with detailed error and circuit analysis for CMOS-45 nm technology node. • The approximate divider presented is reconfigurable in runtime which enables accuracy configurability by varying the design parameter. • Reconfigurable half and full subtractor cells are designed and proposed which achieves dual mode of operation — accurate and exact with energy savings. • Overflow detector circuit for divider design is proposed and presented which is scalable and hardware efficient. • The approximate divider designs are evaluated for image processing applications and found to be satisfactory in terms of Quality of Services (QoS). [ABSTRACT FROM AUTHOR]

The development of systems that can predict epileptic seizures in real-time offers great hope for epilepsy patients. These systems aim to prevent accidents that patients may experience caused by the loss of consciousness during seizures. Therefore, patients must use real-time epileptic seizure prediction systems that do not interfere with their daily activities. In this study, using the unipolar EEG data from a surface electrode, a patient-specific estimation system is implemented in real-time on a system on chip (SoC) that contains an embedded processor and programmable logic blocks. The European epilepsy database EPILEPSIAE is used in the scope of this work. In the proposed system, pre-processing is applied to the EEG data. Then, the features of the data in the frequency domain are extracted. The classifier model is trained with the RusBoosted Tree cluster classifier, which is a machine learning algorithm. Testing is carried out using the proposed classification model. Threshold values are determined, and then false alarms and erroneous classifications are prevented by post-processing. At the end of the tests, prediction success, sensitivity (SEN), Specificity (SPE), False Prediction Rate (FPR), and prediction times are obtained as 77.30%, 95.94%, 0.041 h−1, and 33.23 min, respectively. The proposed system outperforms other studies in the literature in the number of electrodes, real-time operation, hardware/software architecture, and FPR performance. A wearable seizure prediction system seems to be commercialized according to the results achieved in this study. [ABSTRACT FROM AUTHOR]

As an application of his Material Theory of Induction, Norton (2018; manuscript) argues that the correct inductive logic for a fair infinite lottery, and also for evaluating eternal inflation multiverse models, is radically different from standard probability theory. This is due to a requirement of label independence. It follows, Norton argues, that finite additivity fails, and any two sets of outcomes with the same cardinality and co-cardinality have the same chance. This makes the logic useless for evaluating multiverse models based on self-locating chances, so Norton claims that we should despair of such attempts. However, his negative results depend on a certain reification of chance, consisting in the treatment of inductive support as the value of a function, a value not itself affected by relabeling. Here we define a purely comparative infinite lottery logic, where there are no primitive chances but only a relation of 'at most as likely' and its derivatives. This logic satisfies both label independence and a comparative version of additivity as well as several other desirable properties, and it draws finer distinctions between events than Norton's. Consequently, it yields better advice about choosing between sets of lottery tickets than Norton's, but it does not appear to be any more helpful for evaluating multiverse models. Hence, the limitations of Norton's logic are not entirely due to the failure of additivity, nor to the fact that all infinite, co-infinite sets of outcomes have the same chance, but to a more fundamental problem: We have no well-motivated way of comparing disjoint countably infinite sets. • Exhibits a comparative theory of chance for label-independent infinite lotteries. • The comparative theory is additive, regular, and finer than Norton's. • Yet, it is not likely to be useful for evaluating multiverse cosmologies. • We have no basis for assigning relative chances to disjoint infinite sets of worlds. [ABSTRACT FROM AUTHOR]

The decision problem for Propositional Projection Temporal Logic (PPTL) has been solved successfully, however time complexity of the procedure is increased exponentially to the length of the formula. To solve the problem, a labeled unified complete normal form is introduced as the intermediate form to rewrite a PPTL formula into its equivalent labeled normal form, based on which the labeled normal form graph is constructed, and an efficient decision procedure for PPTL is formalized with the time complexity linear to the length of the formula and the size of the power set of the atomic propositions in the formula. Besides, an example is given to show how the improved decision procedure works. [ABSTRACT FROM AUTHOR]

Formal methods are introduced into system designing and testing for realizing high-reliability system. However, the use of these techniques still remain restrictive, due to their redundancies. Most engineers fulfill their activities with natural languages, the specifications described in a natural language are indispensable. For applying the formal method, the specifications in natural language should be translated into a formal language expressly. While, the specifications in the formal language should be retranslated once again in the natural language for execution tests using actual software and/or product. Those redundancies are reasons why the formal methods cannot penetrate into actual industries. To solve these redundancies, algorithms for converting sentences in specification documents into semi-formal descriptions automatically, and visualizing logical relations among semi-formal descriptions are proposed in the paper. [ABSTRACT FROM AUTHOR]

In the last years, some extensions of ω -regular languages, namely, ωB -regular (ω -regular languages extended with boundedness), ωS -regular (ω -regular languages extended with strong unboundedness), and ωBS -regular languages (the combination of ωB - and ωS -regular ones), have been proposed in the literature. While the first two classes satisfy a generalized closure property, which states that the complement of an ωB -regular (resp., ωS -regular) language is an ωS -regular (resp., ωB -regular) one, the last class is not closed under complementation. The existence of non- ωBS -regular languages that are the complements of some ωBS -regular ones and express fairly natural asymptotic behaviors motivates the search for other significant classes of extended ω -regular languages. In this paper, we present the class of ωT -regular languages, which includes meaningful languages that are not ωBS -regular. We define this new class of languages in terms of ωT -regular expressions. Then, we introduce a new class of automata (counter-check automata) and we prove that (i) their emptiness problem is decidable in PTIME, and (ii) they are expressive enough to capture ωT -regular languages. We also provide an encoding of ωT -regular expressions into S1S + U. Finally, we investigate a stronger variant of ωT -regular languages (ω T s -regular languages). We characterize the resulting class of languages in terms of ω T s -regular expressions, and we show how to map it into a suitable class of automata, called counter-queue automata. We conclude the paper with a comparison of the expressiveness of ωT - and ω T s -regular languages and of the corresponding automata. [ABSTRACT FROM AUTHOR]

Several type systems have been proposed to statically control the time complexity of lambda-calculus programs and characterize complexity classes such as FPTIME or FEXPTIME. A first line of research stems from linear logic and restricted versions of its !-modality controlling duplication. An instance of this is light linear logic for polynomial time computation [5]. A second approach relies on the idea of tracking the size increase between input and output, and together with a restricted recursion scheme, to deduce time complexity bounds. This second approach is illustrated for instance by non-size-increasing types [8]. However, both approaches suffer from limitations. The first one, that of linear logic, has a limited intensional expressivity, that is to say some natural polynomial time programs are not typable. As to the second approach it is essentially linear, more precisely it does not allow for a non-linear use of functional arguments. In the present work we incorporate both approaches into a common type system, in order to overcome their respective constraints. The source language we consider is a lambda-calculus with data-types and iteration, that is to say a variant of Gödel's system T. Our goal is to design a system for this language allowing both to handle non-linear functional arguments and to keep a good intensional expressivity. We illustrate our methodology by choosing the system of elementary linear logic (ELL) and combining it with a system of linear size types. We discuss the expressivity of this new type system, called sEAL, and prove that it gives a characterization of the complexity classes FPTIME and 2k-FEXPTIME, for k ≥ 0. [ABSTRACT FROM AUTHOR]

• Process Controls, especially programmable logic control, is an area of educational need. • Herein equipment and activities are described for programmable logic controls instruction. • Activities and equipment are shown in sufficient detail for implementation. • Alumni feedback showed the impact and industrial relevance of the activities and equipment. Programmable logic controllers are ubiquitous in automation practice and 74% of process controls job advertisements seek applicant familiarity with this equipment. However, undergraduate training on these devices is lacking, likely due to expense and pedagogical uncertainty. Without a clear view of how to teach logic controllers little justifies the purchase of these devices in teaching laboratories and engineering programs. During the modernization of process control exercises at the University of Colorado Boulder a finite state machine framework, common to engineering practice, was used to teach programmable logic controllers. Herein we describe this approach, which reliably guided an undergraduate activity where actual commercial controllers drove engineering automation. Ultimately, the cost of a single apparatus was $2,294US, which appeared warranted given feedback from 84 alumni and closer curricular alignment with industrial needs. [ABSTRACT FROM AUTHOR]

Data acquisition systems are crucial when implementing control and automation strategies correctly and on time. The knowledge of the sampling time is one of the relevant features to ensure that the sampled data properly represent the process variable. This paper describes the development of a performance index to measure continuously and in real-time the sampling time behavior of typical control and automation systems. To test this index two different architectures are used. The first one uses a data acquisition board plugged directly into the computer bus, and the second one uses a Programmable Logic Controller communicating with a computer through either Industrial Ethernet with OPC or the serial Modbus RTU protocol. In all cases, a custom software application is implemented to calculate the performance index when the sampling time is provided by the Operating System's timer interrupt service. The analysis of the experimental results shows that the proposed performance index can be useful to assess the sampling time behavior or to assist in decision-making about hardware and software choices. • A performance index is proposed to assess the sampling time accuracy • The performance index can capture the effects of outliers, bias and jitter. • The sampling time behavior is affected by the operating system's timer services. • The best values of the index are obtained with a real-time operating system. • Systems with a data acquisition board show a better index than those with a PLC [ABSTRACT FROM AUTHOR]

Maritime transport is an indispensable element of the global logistics network. Most maritime loading-unloading operations are supported by quay cranes, making their availability and condition critical to port operations. This work identifies discordant trends arising during the vibration-based condition monitoring of these quay cranes in one of the busiest container ports in the United Kingdom. This work proposes an unsupervised and constrained discord detection approach for irregular but near real-time time series data obtained from multi-modal IoT-based condition monitoring sensors installed on these cranes and transmitted over a 5G network. Due to the live nature of the seaport's operations, the development of controlled anomaly signatures for a baseline reference was not possible. To address the challenges of incomplete asset health information, irregular and batched time-series sensor data, massive data volumes, and the lack of the assets' vibration signature baselines, this paper proposes an unsupervised, robust, and fast discord detection mechanism that can rapidly highlight discordant time-series chunks in the received vibration data at a central server. A Support Vector Machine based One-Class Classifier (OCC-SVM) is used to identify the discordant vibration signatures in the time series data. During the development of this approach, the timestamped data chunks from the add-on IoT-based vibration sensors were clustered into two weight classes (loaded and unloaded) based on the crane's default Programmable Logic Controller (PLC) sensors. The efficacy of this method is checked against the crane maintenance logs and data from a separate crane's vibration and PLC data. Further, a method for generating synthetic noise-embedded vibration signatures to test the effectiveness of the discord detection method has been devised. Finally, the practicality of the proposed OCC-SVM approach for discord detection was inspected in a constrained environment setting. [ABSTRACT FROM AUTHOR]