Function Block Research Articles

Use of a Hybrid Cardiac Resynchronisation-P/Subcutaneous Implantable Cardioverter Defibrillator System to Avoid High-Risk Defibrillator Lead Extraction

A 71-year-old man with sinus node disease initially had a dual-chamber pacemaker implanted in 2007. Six months later, ventricular tachycardia was detected on interrogation of his pacemaker and a transthoracic echocardiogram confirmed moderate global left ventricular (LV) dysfunction. Following exclusion of coronary ischaemia, he underwent an upgrade to an implantable cardioverter defibrillator (ICD). In 2011, he underwent an end-of-life generator replacement; he was in complete heart block at that time. Both leads demonstrated satisfactory parameters. In 2012, he had a ventricular tachycardia storm resulting in numerous deliveries of therapy. Owing to persistent New York Heart Association-III symptoms with moderately impaired LV function and pacing-induced left bundle branch block, a cardiac resynchronisation defibrillator was indicated. At implant, an ipsilateral venogram revealed subclavian stenosis; however, a coronary sinus lead was able to be advanced to provide LV pacing. On disconnecting the DF1 right ventricular (RV) shock lead from the device, an insulation breach close to the RV distal coil pin was noted. Owing to subclavian stenosis, a new DF4 lead could not be advanced, and lead extraction was deemed high risk. Thus, the pace/sense IS-1 pin, right atrial, and LV leads were attached to a cardiac resynchronisation-P, all demonstrating satisfactory parameters. The following day, he underwent screening and subsequent implantation of a subcutaneous defibrillator. At 1-year follow-up, both device parameters were satisfactory, he was free of heart failure signs and symptoms, without any arrhythmias detected or therapies delivered.

Emulation of Cyber-Physical Systems Using IEC-61499

Automation systems used in smart grids, transportation, and medical electronics are cyber physical in nature. Automation standards, such as IEC-61499, while well suited to the design of discrete controllers, are not ideally suited to model the dynamics of the plant. Such modeling is essential for emulation-based validation of the controllers in the cyber-physical systems (CPS) domain. We use a well-known formal model for CPS, called hybrid input output automata (HIOA), as the main vehicle in the proposed formulation. A physical process (the plant) may be described as a synchronous composition of a network of such HIOA. We provide an approach to transform such a network to a composite function block (CFB) in IEC-61499. This transformation is shown to be semantics preserving. Code generated from such plant models can be executed on a computer chip to provide real-time response to their adjoining controllers. Through practical examples, we illustrate the scalability and practicability of the proposed approach. The developed approach enables the emulation of physical processes in industrial automation without using the actual plant.

Software behaviour analysis method based on behaviour template

This paper proposes a software behaviours analysis method based on behaviour template (SABT), which according to the context of source code, builds a behaviour template to detect software malicious behaviour based on function transfer map and minimum function blocks. In the present research, many methods used state transfer diagram to build software behaviour model. Our method is based on the corresponding relationship between the functions and system call sequence, which ensures the accuracy of the malicious behaviour detection. Compared with traditional methods, such as N-gram, FSA, and Var-gram, SABT can get higher cover rate of code and detect abnormal behaviour more effectively and efficiently.

Unbalance Level Regulating Algorithm in Power Distribution Networks

The paper dwells on the unified power quality indexes characterizing the phenomenon of voltage unbalance in three-phase systems. Voltage unbalance is one of the commonest occurrences in the town mains of 0.38 kV voltage. The phenomenon describes as inequality of vector magnitude of phase voltage and shearing angle between them. Causes and consequences of the voltage unbalance in distribution networks have been considered. The algorithm, which allows switching one-phase load, has been developed as one of the methods of reducing the unbalance level. The algorithm is written in the function block diagram programming language. For determining the duration and magnitude of the unbalance level it is proposed to introduce the forecasting algorithm. The necessary data for forecasting are accumulated in the course of the algorithm based on the Function Block Diagram. The algorithm example is given for transforming substation of the urban electrical power supply system. The results of the economic efficiency assessment of the algorithm implementation are shown in conclusion. The use of automatic switching of the one-phase load for explored substation allows reducing energy losses (active electric energy by 7.63%; reactive energy by 8.37%). It also allows improving supply quality to a consumer. For explored substation the average zero-sequence unbalance factor has dropped from 3.59% to 2.13%, and the negative-sequence unbalance factor has dropped from 0.61% to 0.36%.

Conducting functional control of field-programmable gate arrays

Approaches to accomplishing functional control of field-programmable gate arrays (FPGA) are described. The first part of the article describes the existing equipment that allows conducting functional tests of FPGAs. A table comparing the main parameters of the equipment available in the market is given. The table contains the main parameters of the equipment that make it possible to simplify the process of conducting functional tests of FPGAs. The main advantages and disadvantages of using this equipment are shown on the basis of the analysis. In the second part of the article the author describes the main methods of conducting functional tests of FPGAs. When developing algorithms, the author divides all the internal structure of a FPGA into two functionally independent parts. The first part is the internal programmable logic, and the second part contains functional blocks built into a FPGA. The article gives examples of algorithms developed on the basis of the methods described and configuration firm-ware produced with the help of these algorithms. The developed algorithms carry out functional control of the internal logic, as well as of function blocks built into a FPGA. To develop algorithms for functional control of internal logic the author uses the method of iterative logic arrays. A method of creating built- in self-test structures is used for the control of function blocks built into a FPGA. In the final part the author draws conclusions and describes the directions of his further research.

Construction of CFC-Programs by LTL-Specification

This article continues a cycle of papers, which describe an approach to construction and verification of discrete PLC-programs by an LTL-specification. The approach provides a possibility of PLC-program correctness analysis by the model checking method. For the specification of the program behaviour the linear-time temporal logic LTL is used. The correctness analysis of an LTL specification is performed automatically by the symbolic model checking tool Cadence SMV. It was previously shown how ST-, LD- and IL-programs are constructed by a correct (with verified program properties) LTL-specification. In this article, a technology of CFC-program construction by an LTL-specification is described. The language CFC (Continuous Function Chart) is a variation of FBD (Function Block Diagram). FBD is a graphical language for microcircuits. CFC provides a possibility of free allocation of program components and connections on a screen. The approach to construction of CFC-programs is shown by an example. PLC-program representation on CFC within the approach to programming by LTLspecification differs from other representations. It gives the visualization of a data flow from inputs to outputs. The influence and dependence among variables is explicitly shown during the program execution within one PLC working cycle. In fact, CFC-program is a scheme of PLC-program data flow.

Mechanical dispersion is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks

Objectives: Bundle branch blocks (BBB)-related mechanical dyssynchrony and dispersion may improve patient selection for device therapy, but their effect on the natural history of this patient population is unknown.Methods: A total of 155 patients with LVEF ≤ 35% and BBB, not treated with device therapy, were included. Mechanical dyssynchrony was defined as the presence of either septal flash or apical rocking. Contraction duration was assessed as time interval from the electrocardiographic R-(Q-)wave to peak longitudinal strain in each of 17 left ventricular segments. Mechanical dispersion was defined as either the standard deviation of all time intervals (dispersionSD) or as the difference between the longest and shortest time intervals (dispersiondelta). Patients were followed for cardiac mortality during a median period of 33 months.Results: Mechanical dyssynchrony was not associated with survival. More pronounced mechanical dispersiondelta was found in patients with dyssynchrony than in those without. In the multivariate regression analysis, patients’ functional class, diabetes mellitus and dispersiondelta were independently associated with mortality.Conclusions: Mechanical dispersion, but not dyssynchrony, was independently associated with mortality and it may be useful for risk stratification of patients with heart failure (HF) and BBB.Key MessagesMechanical dispersion, measured by strain echocardiography, is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks.Mechanical dispersion may be useful for risk stratification of patients with heart failure and bundle branch blocks.

Programming a Pneumatic Processes Sequence based on PLC by Demonstration

Abstract
 Pneumatic processes sequence (PPS) is used widely in industrial applications. It is common to do a predetermined PPS to achieve a specific larger task within the industrial application like the PPS achieved by the pick and place industrial robot arm. This sequence may require change depending on changing the required task and usually this requires the programmer intervention to change the sequence’ sprogram, which is costly and may take long time. In this research a PLC-based PPS control system is designed and implemented, in which the PPS is programmed by demonstration. The PPS could be changed by demonstrating the new required sequence via the user by following simple series of manual steps without having to change the PLC’s original program, which leads to decreasing the cost and time.
 Keywords: FIFO function block, Programming by Demonstration (PbD), System Frame.

Function Block for Rotary Kiln Coating Disintegration Detection

Condition monitoring is an important field that can boost manufacturing processes to produce high quality and more quantities. This work presents the design of new Programmable Logic Controller (PLC) Function Block (FB) dedicated to the instantaneous detection of any coating piece disintegration from the wall coating formed by the processed material sticking naturally on the inner side of the cement rotary kiln. The detection is based on the on-line analysis of the kiln spinning electrical motor’s signal. The FB makes use of differences between the adjacent signal’s measurements values and logic functions to hide false alarms for the user whenever they break out due to kiln velocity set point abrupt changes. In steady state process operation, the technique provides highly reliable and accurate detection. Its application can be extended to any similar instantaneous abrupt changes occurring in other manufacturing processes.

A Combined Voltage Control Strategy for Fuel Cell

Control of output voltage is critical for the power quality of solid oxide fuel cells (SOFCs), which is, however, challenging due to electrochemical nonlinearity, load disturbances, modelling uncertainties, and actuator constraints. Moreover, the fuel utilization rate should be limited within a safety range during the voltage regulation transient. The current research is usually appealing to model predictive control (MPC) by formulating the difficulties into a constrained optimization problem, but its huge computational complexity makes it formidable for real-time implementation in practice. To this end, this paper aims to develop a combined control structure, with basic function blocks, to fulfill the objectives with minor computation. Firstly, the disturbance, nonlinearity and uncertainties are lumped as a total disturbance, which is estimated and mitigated by active disturbance rejection controller (ADRC). Secondly, a feed-forward controller is introduced to improve the load disturbance rejection response. Finally, the constraints are satisfied by designing a cautious switching strategy. The simulation results show that the nominal performance of the proposed strategy is comparable to MPC. In the presence of parameter perturbation, the proposed strategy shows a better performance than MPC.

Formal verification considering a systematic modeling approach for function blocks

Formal verification of automation systems controller software is a complex task. This happens mainly because this kind of systems need to be programmed by highly skilled designers as results obtained from formal verification are highly dependent of the “quality” of the developed models. In this paper, is explained and presented an approach for modeling a series of function blocks from IEC 61 131-3 standard and, in the same context, is proposed an approach for developing the respective Timed Automata model for formal verification purposes, by model-checking, using UPPAAL model-checker. Some interesting results are achieved and the proposed approach is user friendly.

Restoration of TET2 Function Blocks Aberrant Self-Renewal and Leukemia Progression

Loss-of-function mutations in TET2 occur frequently in patients with clonal hematopoiesis, myelodysplastic syndrome (MDS), and acute myeloid leukemia (AML) and are associated with a DNA hypermethylation phenotype. To determine the role of TET2 deficiency in leukemia stem cell maintenance, we generated a reversible transgenic RNAi mouse to model restoration of endogenous Tet2 expression. Tet2 restoration reverses aberrant hematopoietic stem and progenitor cell (HSPC) self-renewal invitro and invivo. Treatment with vitamin C, a co-factor of Fe2+ and α-KG-dependent dioxygenases, mimics TET2 restoration by enhancing 5-hydroxymethylcytosine formation in Tet2-deficient mouse HSPCs and suppresses human leukemic colony formation and leukemia progression of primary human leukemia PDXs. Vitamin C also drives DNA hypomethylation and expression of a TET2-dependent gene signature in human leukemia cell lines. Furthermore, TET-mediated DNA oxidation induced by vitamin C treatment in leukemia cells enhances their sensitivity to PARP inhibition and could provide a safe and effective combination strategy to selectively target TET deficiency in cancer. PAPERCLIP.

Proximal arm non-use when reaching after a stroke.

After a stroke, many people "cannot and do not" use their paretic upper limb. With recovery, some people "can but do not" use their paretic upper limb and this non-use should be counteracted with specific rehabilitation. The aim of the study was to quantify one aspect of the non-use: proximal arm non-use when reaching within one's arm length in 45 post-stroke and 45 age matched controls. Arm use refers to the contribution of the shoulder and elbow motion to the hand movement towards the target. Proximal arm non-use is calculated as the ratio of the difference between spontaneous arm use and maximal arm use. We found that proximal arm non-use has very good test-retest reliability, does not depend on time since stroke, increases with impairment (Fugl-Meyer) and loss of function (Box & Block), and most importantly, that 61% of patients with lower impairment (Fugl-Meyer >28/42) exhibit proximal arm non-use. We conclude that quantifying proximal arm non-use in post-stroke individuals provides novel information that complements routine clinical measures. It is likely that proximal arm non-use quantifies one aspect of the motor reserve that therapists can target in patient specific rehabilitation programs.

P1440Mechanical dispersion but not dyssynchrony is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks

P1440Mechanical dispersion but not dyssynchrony is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks

An innovative approach for modeling and simulation of an automated industrial robotic arm operated electro-pneumatically

The article is focused on modeling an automated industrial robotic arm operated electro-pneumatically and to simulate the robotic arm operation. It is used the graphic language FBD (Function Block Diagram) to program the robotic arm on Zelio Logic automation. The innovative modeling and simulation procedures are considered specific problems regarding the development of a new type of technical products in the field of robotics. Thus, were identified new applications of a Programmable Logic Controller (PLC) as a specialized computer performing control functions with a variety of high levels of complexit.

A cloud-based, knowledge-enriched framework for increasing machining efficiency based on machine tool monitoring

The ever-increasing complexity in manufacturing systems caused by the fluctuating customer demands has highly affected the contemporary shop-floors. The selection of the appropriate cutting parameters is becoming more and more challenging due to the increasing complexity of products. Until now, the knowledge of the machine operators concerning the modification of the machining parameters and the monitoring information is not sufficiently exploited by the optimization systems. Web and Cloud technologies together with wireless sensor networks are required to capture the shop-floor data and enable the ubiquitous access from multiple IT tools. For addressing these challenges, this research work proposes a Cloud-based, knowledge-enriched framework for machining efficiency based on machine tool monitoring. More precisely, it focuses on the optimization of the machining parameters and moves through an event-driven optimization algorithm, utilizing the existing machining knowledge captured by the monitoring system. Based on the features of a new part, a similarity mechanism retrieves the cutting parameters of successfully executed past parts that have been machined. Afterwards, the optimization module, using event-driven function blocks, adapts these parameters to efficiently optimize the moves and the cutting parameters. The monitoring system uses a wireless sensor network and a human operator input via mobile devices. A case study from the mould-making industry is used for validating the proposed framework.

Implementación de sistemas distribuidos de bajo costo bajo norma IEC-61499, en la estación de clasificación y manipulación del MPS 500

<p>El desarrollo de las tecnologías, los requerimientos de nuevas prestaciones y las limitantes dadas por los fabricantes de software y hardware para la automatización ha hecho que nuevos estándares sean desarrollados. El presente trabajo tiene como propósito la implantación de un sistema distribuido de bajo costo, usando la norma IEC-61499 en la estación de clasificación y manipulación del MPS-500. En estos módulos se pueden dar problemas de aplicaciones industriales reales. IEC-61499 estandariza un entorno de programación para sistemas distribuidos y tiene un alto nivel de versatilidad para el diseño de sistemas, pues combina software y hardware de manera independiente. Se utilizó el <em>softwar</em>e 4DIAC y se crearon nuevos bloques de función (FB) para el control del proceso y el <em>runtime</em> FORTE fue ejecutado en una tarjeta Raspberry Pi. La norma IEC-61499 permite al diseñador del sistema crear un modelo de ejecución de bloques de función conducido por eventos, de esta manera, puede dar prioridad a la orden de ejecución y modificar fácilmente algún parámetro de la planta.</p>

SLAE-CPS: Smart Lean Automation Engine Enabled by Cyber-Physical Systems Technologies.

In the context of Industry 4.0, the demand for the mass production of highly customized products will lead to complex products and an increasing demand for production system flexibility. Simply implementing lean production-based human-centered production or high automation to improve system flexibility is insufficient. Currently, lean automation (Jidoka) that utilizes cyber-physical systems (CPS) is considered a cost-efficient and effective approach for improving system flexibility under shrinking global economic conditions. Therefore, a smart lean automation engine enabled by CPS technologies (SLAE–CPS), which is based on an analysis of Jidoka functions and the smart capacity of CPS technologies, is proposed in this study to provide an integrated and standardized approach to design and implement a CPS-based smart Jidoka system. A set of comprehensive architecture and standardized key technologies should be presented to achieve the above-mentioned goal. Therefore, a distributed architecture that joins service-oriented architecture, agent, function block (FB), cloud, and Internet of things is proposed to support the flexible configuration, deployment, and performance of SLAE–CPS. Then, several standardized key techniques are proposed under this architecture. The first one is for converting heterogeneous physical data into uniform services for subsequent abnormality analysis and detection. The second one is a set of Jidoka scene rules, which is abstracted based on the analysis of the operator, machine, material, quality, and other factors in different time dimensions. These Jidoka rules can support executive FBs in performing different Jidoka functions. Finally, supported by the integrated and standardized approach of our proposed engine, a case study is conducted to verify the current research results. The proposed SLAE–CPS can serve as an important reference value for combining the benefits of innovative technology and proper methodology.

Ubiquitous manufacturing system based on Cloud: A robotics application

Modern manufacturing industry calls for a new generation of production system with better interoperability and new business models. As a novel information technology, Cloud provides new service models and business opportunities for manufacturing industry. In this research, recent Cloud manufacturing and Cloud robotics approaches are reviewed. Function block-based integration mechanisms are developed to integrate various types of manufacturing facilities. A Cloud-based manufacturing system is developed to support ubiquitous manufacturing, which provides a service pool maintaining physical facilities in terms of manufacturing services. The proposed framework and mechanisms are evaluated by both machining and robotics applications. In practice, it is possible to establish an integrated manufacturing environment across multiple levels with the support of manufacturing Cloud and function blocks. It provides a flexible architecture as well as ubiquitous and integrated methodologies for the Cloud manufacturing system. A ubiquitous manufacturing system based on Cloud manufacturing.Industrial robots utilized as implementation applications in the Ubiquitous manufacturing environment.Systematic analysis and guidelines for adpoting advanced manufacturing technologies.Multiple deployment models for private, community and public scenarios.Proposed system is implemented and evaluated in the near-real manufacturing environment.

Translation of IEC 61131-3 Function Block Diagrams to PVS for Formal Verification with Real-Time Nuclear Application

The trip computers for the two reactor shutdown systems of the Ontario Power Generation (OPG) Darlington Nuclear Power Generating Station are being refurbished due to hardware obsolescence. For one of the systems, the general purpose computer originally used is being replaced by a programmable logic controller (PLC). The trip computer application software has been rewritten using function block diagrams (FBDs), a commonly used PLC programming language defined in the IEC 61131-3 standard. The replacement project’s quality assurance program requires that formal verification be performed to compare the FBDs against a formal software requirements specification written using tabular expressions (TEs). The PVS theorem proving tool is used in formal verification. Custom tools developed for OPG are used to translate TEs and FBDs into PVS code. In this paper, we present a method to rigorously translate the graphical FBD language to a mathematical model in PVS using an abstract syntax to represent the FBD constructs. We use an example from the replacement project to demonstrate the use of the model to translate a FBD module into a PVS specification. We then extend that example to demonstrate the method’s applicability to a Simulink-based design.