Function Block Research Articles

Software Reliability definition in the modern information system structure

The subject of research is the use of modern approaches to determine aimed at improving the reliability of software security and quality of the information system. The object of research is a model determining the reliability of the software. The author examines in detail aspects such topics as: the use of a functional approach to the study of the reliability of the software component is the sum of the aggregate reliability to achieve each function block; Use a systematic approach to the study of the reliability of the software in the information system structure. Particular attention is paid to the comparison of existing models and methods of determining the reliability. The proposed method of estimating software reliability based on the allocation of the function blocks and to guarantee quality and reliability of the final result of software development. Key findings of the study: the use of a systematic approach makes it possible to identify the quality of the following interconnections between the constituent elements of the program, which define modern ways to improve software reliability. The paper proposed to adapt the major principles of the system improve the reliability of software proved useful effect of their introduction. The novelty of the research lies in the joint use of the functional and systemic approach in order to identify ways to increase the quality and reliability that takes into account the characteristics within the structural elements of the program and their interaction.

Wind Energy Dynamics of the Separately Excited Induction Generator

This paper covers the analysis, dynamic modelling and control of an isolated self-excited induction generator (SEIG) driven by a wind turbine. The proposed dynamic model consists of induction generator, self-excitation capacitance and load model which are expressed in stationary d-q reference frame. The dynamic performance of SEIG is investigated under no load and on load. To predict the performance of the system, a MATLAB based simulation study using matlab embedded function block was carried out. Simulations from the variations of the speed and load display the dynamic behavior of the generator. A constant capacitor value of 100 micro-farads was used in this work. The simulation results obtained illustrate the changes in the voltage, currents, torque and magnetizing inductance of the generator. The wind velocity increase led to the increase in mechanical input from the wind turbine. This results in the increased rotor speed leading also to increased stator phase voltage. The obtained simulations also show that the output voltage of the induction generator depends greatly on its shaft speed and load; this poses a potential threat as it is capable of causing a significant variation in the power consumption in the load of the machine.

Unified and Integrated Circuit Antenna in Front End—A Proof of Concept

A concept of seamlessly colocated and cointegrated antennas and front-end chain circuits in the form of a unified and integrated design space is proposed, studied, and demonstrated in this paper, which strives to create future joint circuiting-radiating front-end analog functional blocks. To show the proposed concept, the building elements involving dual-function amplifier antenna are highlighted as an example and arranged in a series-connected array, each acting simultaneously as a matching circuit and transmitting antenna. In other words, a single geometrical space serves as both circuits and antennas, meaning a space overlap in which the circuit is an antenna and the antenna is a circuit. This reflects both the harmony and harmonious relationship of the circuit antenna. In this paper, the spacing between two neighboring array elements is utilized to accommodate active devices, such as transistors, in this example. As the first theoretical and experimental demonstration, this paper involves the design of patch antennas, the analysis of mutual coupling, and the placement of amplifying transistors in different operation modes. The modeling procedure for a $1 \times N$ amplifier-antenna system is presented. The proposed concept is experimentally validated by prototyping a $1 \times 2$ amplifier-antenna array at 5 GHz with rectangular patches and off-the-shell HJ-FET. An equivalent circuit network is established for the proposed dual function block. Measured results show that the experimental block has −10 dB matching bandwidth of 125 MHz at the steering angle of +30° with an amplifying gain of 11.5 dB. It is also experimentally illustrated that frequency tuning and beam steering can easily be enabled by varying the dc bias. The design of $1 \times 4$ amplifier-antenna array at 5 GHz is also discussed to generalize the proposed theory and guide the design of higher order amplifier arrays.

Function Block Finite-State Model Identification Using SAT and CSP Solvers

We propose a two-stage exact approach for identifying finite-state models of function blocks based on given execution traces. First, a base finite-state model is inferred with a method based on translation to the Boolean satisfiability problem, and then, the base model is generalized by inferring minimal guard conditions of the state machine with a method based on translation to the constraint satisfaction problem.

A Novel Systolic Parallel Hardware Architecture for the FPGA Acceleration of Feedforward Neural Networks

New chips for machine learning applications appear, they are tuned for a specific topology, being efficient by using highly parallel designs at the cost of high power or large complex devices. However, the computational demands of deep neural networks require flexible and efficient hardware architectures able to fit different applications, neural network types, number of inputs, outputs, layers, and units in each layer, making the migration from software to hardware easy. This paper describes novel hardware implementing any feedforward neural network (FFNN): multilayer perceptron, autoencoder, and logistic regression. The architecture admits an arbitrary input and output number, units in layers, and a number of layers. The hardware combines matrix algebra concepts with serial-parallel computation. It is based on a systolic ring of neural processing elements (NPE), only requiring as many NPEs as neuron units in the largest layer, no matter the number of layers. The use of resources grows linearly with the number of NPEs. This versatile architecture serves as an accelerator in real-time applications and its size does not affect the system clock frequency. Unlike most approaches, a single activation function block (AFB) for the whole FFNN is required. Performance, resource usage, and accuracy for several network topologies and activation functions are evaluated. The architecture reaches 550 MHz clock speed in a Virtex7 FPGA. The proposed implementation uses 18-bit fixed point achieving similar classification performance to a floating point approach. A reduced weight bit size does not affect the accuracy, allowing more weights in the same memory. Different FFNN for Iris and MNIST datasets were evaluated and, for a real-time application of abnormal cardiac detection, a ${\hspace{-0.112em}\times \hspace{-0.112em}}256$ acceleration was achieved. The proposed architecture can perform up to 1980 Giga operations per second (GOPS), implementing the multilayer FFNN of up to 3600 neurons per layer in a single chip. The architecture can be extended to bigger capacity devices or multi-chip by the simple NPE ring extension.

Reduction of EMI Noise Due to Nonideal Interleaving in a 100 kW SiC PV Converter

A Grid-tied inverter utilizing wide bandgap devices can achieve higher switching frequency resulting in a power filter with reduced size and weight. However, the increased switching frequency may lead to more switching harmonics entering the electromagnetic interference (EMI) frequency range, which will increase the size of EMI filter. Interleaving paralleled converters can cancel some of the switching harmonics and reduce the size of EMI filter. However, nonideal interleaving will deteriorate the harmonic canceling effect. In this research, the nonideal effects are found to be from the small mismatch of the pulsewidth of the interleaving legs and the mismatch of the impedance between the interleaving legs. A modulation method is proposed to completely eliminate the pulsewidth mismatch. Compared with other solutions, the proposed method does not require the information of filter parameters, neither gate driver synchronization, and nor a special function block of the digital controller. The proposed modulation was implemented on a 150 MHz digital signal processor and a 100 MHz field-programmable gate array, and was experimentally verified on a 100 kW parallel coupled SiC PV inverter prototype.

Dynamic Modelling and Simulation of an Induction Motor with Completely Reduced Stator Transients

Dynamic modelling and simulation of an induction motor is of great significance both in the academic and in the industrial world. The characteristics of an induction motor are represented mathematically. The mathematical representation is modeled with MATLAB/SIMULINK software. The main advantage of this software over other programming soft wares is that, instead of compilation of program code, the simulation model is built up systematically by means of basic function blocks. The dynamic properties of the induction motor are determined from the graphs obtained from the software. A reduced model of the induction motor is modeled by setting the stator transients to zero. In this paper, the complete model and the reduced model are compared. From the results obtained, the reduced model can sufficiently represent the dynamic characteristics of an induction motor - the currents, and rotor speed of the induction motor. Equally, from the results obtained, the torque dynamic characteristics of the motor are however not satisfactorily represented by the reduced model.

FPGA-based implementation of bistable function blocks defined in the IEC 61131

This article discusses the possibilities of using FPGAs in order to construct fast PLCs that execute serial-cyclic program control loop. The PLCs bistable function blocks of the IEC 61131-3 standard with particular emphasis on the possible FPGA implementations are presented. The FPGA hardware support is implemented in such a way that it does not interfere with the normal, serial-cyclic program execution. It enables a significant reduction in the timing of the result execution after loading new input data in the memory cells. Moreover, such an implementation of bistable function blocks allows for seamless use in any programming language. Both the IL text language and the graphical languages (LD and FBD) can freely use the advantages of such a solution.

Implementation of IEC 61499 and Model Checking for Drill Simulator

Reusability of control codes is one of the basic angles in mechanical robotization, especially for the advancement of high dependable control frameworks. In this paper, we examine a general structure and usage of IEC 61499 standard that can be utilized to speak to conveyed control frameworks and rebuilding the control programs. This paper likewise expects to change the current IEC 61131 based model of computerization framework into the models that pursues IEC 61499 standard. We utilize a bore test system as precedent by mimicking the model utilizing Function Block Development Kit (FBDK) in light of IEC 61499. Accordingly, a piece of the control codes can be used for reusable reason to accomplish framework control objective.

Design Considerations for Energy-Efficient and Variation-Tolerant Nonvolatile Logic

Systems powered by harvested energy must consume very low power and withstand frequent interruptions in power. Nonvolatile logic (NVL) addresses the latter by saving the system state in flipflops enhanced with spin-transfer torque magnetic tunnel junctions (STT-MTJs) as the nonvolatile storage devices. Manufacturing variations in the STT-MTJs and in CMOS transistors significantly reduce yield, leading to overdesign and high-energy consumption. A detailed analysis of the design tradeoffs in the driver circuitry for performing backup and restore, and a novel method to design the energy optimal driver for a given yield is presented. Next, efficient designs of two nonvolatile flip-flop (NVFF) circuits are presented, in which the backup time is determined on a per-chip basis, resulting in minimizing the energy wastage and satisfying the yield constraint. To achieve a yield of 98%, the conventional approach would have to expend nearly $5\times $ more energy than the minimum required, whereas the proposed tunable approach expends only 26% more energy than the minimum. Also included are the energy consumption of the proposed NVFF designs when used in two larger function blocks. Experimental results were based on a commercial 40-nm process design kit, and HSPICE simulations with foundry supplied statistical models and data.

ИССЛЕДОВАНИЕ МУЛЬТИЭНЕРГЕТИЧЕСКОГО ОБЪЕКТА МЕТОДАМИ ИМИТАЦИОННОГО МОДЕЛИРОВАНИЯ

The purpose of the paper is to consider the design principles of the multi-power hub simulation model, study the power facility by the methods of simulation modeling, analyze the economic efficiency of accumulation of electric power and its conversion into heat energy. The set problem is solved using the theory of energy hubs and the principles of simulation modeling in the MatLab system. The article describes the technical feasibility of a multi-power system implementation. The function block diagram of a multi-power facility made in the MatLab environment is presented. The economic efficiency of multi-power hub principle application is analyzed on example of electric energy accumulation and conversion into heat. The case study shows the efficiency of the developed software for energy hub modeling. The article presents the construction principles of the simulation model of the integrated multi-power system of power supply based on the concept of a power hub. An example of developed simulation model application is given. The proposed approach offers a broad perspective for the study of many significant problems in the integrated power systems with multiple carriers including their properties, features of their growth and operation. This article makes the first small contribution to the discussed important research direction.

Feature-based function block control framework for manufacturing equipment in cloud environments

The ability to adaptively control manufacturing equipment in cloud environments is becoming increasingly more important. Industry 4.0, supported by Cyber Physical Systems and the concept of on-demand, scalable and pay-for-usage resource-sharing in cloud environments offers many promises regarding effective and flexible manufacturing. For implementing the concept of manufacturing services in a cloud environment, a cloud control approach for the sharing and control of networked manufacturing resources is required. This paper presents a cloud service-based control approach which has a product perspective and builds on the combination of event-driven IEC 61499 Function Blocks and product manufacturing features. Distributed control is realised through the use of a networked control structure of such Function Blocks as decision modules, enabling an adaptive run-time behaviour. The control approach has been developed and implemented as prototype systems for both local and distributed manufacturing scenarios, in both real and virtual applications. An application scenario is presented to demonstrate the applicability of the control approach. In this scenario, Assembly Feature-Function Blocks for adaptive control of robotic assembly tasks have been used.

Improvement of Upper Limb Motor Control and Function After Competitive and Noncompetitive Volleyball Exercises in Chronic Stroke Survivors: A Randomized Clinical Trial

ObjectivesTo investigate the effects of competitive and noncompetitive volleyball exercises on the functional performance and motor control of the upper limbs in chronic stroke survivors. DesignRandomized clinical trial. SettingOutpatient rehabilitation center. ParticipantsChronic stroke survivors (N=48). InterventionsParticipants were randomly assigned to competitive (n=16) or noncompetitive (n=16) volleyball exercise groups (60min/d volleyball exercise+30min/d traditional rehabilitation, 3d/wk for 7wk) and control group (n=16). Main Outcome MeasuresReach and grasp motor control measures were evaluated through kinematic analysis. Functional outcomes were assessed via Motor Activity Log, Wolf Motor Function Test (WMFT), Box and Block Test, and Wrist Position Sense Test. ResultsSignificant improvement of functional performance was observed in both competitive (P<.0001) and noncompetitive volleyball exercise groups (P<.01), but not in the control group (P>.05), with the exception of WMFT score. Volleyball training, in general, resulted in more efficient spatiotemporal control of reach and grasp functions, as well as less dependence on feedback control as compared to the control group. Moreover, the competitive volleyball exercise group exhibited greater improvement in both functional performance and motor control levels. ConclusionsVolleyball team exercises, especially in a competitive format, resulted in enhancing the efficacy of the preprogramming and execution of reach and grasp movements, as well as a shift from feedback to feedforward control of the affected upper limb in chronic stroke survivors. This may well be a potential underlying mechanism for improving functional performance.

Majority and Minority Voted Redundancy Scheme for Safety-Critical Applications with Error/No-Error Signaling Logic

In the era of nanoelectronics, multiple faults or failures of function blocks are likely to occur. To withstand these, higher levels of redundancy are suggested to be employed in at least the sensitive portions of a circuit or system. In this context, the N-modular redundancy (NMR) scheme may be used to guard against the multiple faults or failures of function blocks. However, the NMR scheme would exacerbate the weight, cost, and design metrics to implement higher-order redundancy. Hence, as an alternative to the NMR, the majority and minority voted redundancy (MMR) scheme was proposed recently. However, the proposal was restricted to the basic implementation with no provision for indicating the correct or the incorrect operation of the MMR. Hence in this work, we present the MMR scheme with the error/no-error signaling logic (ESL). Example NMR circuits without and with the ESL (NMRESL), and example MMR circuits without and with the proposed ESL (MMRESL) were implemented to achieve similar degrees of fault tolerance using a 32/28-nm CMOS technology. The results show that, on average, the proposed MMRESL circuits have 18.9% less critical path delay, dissipate 64.8% less power, and require 49.5% less silicon area compared to their counterpart NMRESL circuits.

Feature-based adaptive machining for complex freeform surfaces under cloud environment

Abstract Freeform surfaces are used more and more widely in products of aerospace, automotive and watercraft due to excellent aerodynamic and hydrodynamic performance. Could manufacturing provides a promising solution to satisfy the increasing demands in high quality freeform surface machining capability but significantly increase the shop-floor uncertainties, which necessitates adaptive planning and execution of machining services. To address this issue, this paper first introduces the concept of surface dynamic machining feature (SDMF) which considers feature dynamics across different machining steps and uncertain machining resources. Then a machining service modeling method for feature-based freeform surface machining is put forward by combing SDMF with function blocks (FB). Based on the event-driven mechanism of SDMF-FB, the adaptive response of the machining service to machining resource changes could be started from feature model adjusting for a real optimal machining result. At last, a surface part from the real industry is selected as the case to show the advantages of the proposed method.

TORUS

Cyber-Physical Systems (CPS) contain intertwined and distributed software, hardware, and physical components to control complex physical processes. They find wide application in industrial systems, such as smart grid protection systems, which face increasingly complex communication and computation needs. Due to the scale and complexity of the interactions that occur within CPS, tracing requirements through to the system components and software code that implement them is often hard. Existing requirements management systems do not scale well, and traceability is difficult to implement and maintain in highly heterogeneous systems. However, the information trace that links provide is crucial for supporting testing and certification activities in safety-critical environments such as smart grids. The well-formed models of power systems provided by the IEC 61850 standard and the software design structure provided by the IEC 61499 Function Blocks standard can be leveraged to automate many traceability operations. We present Traceability of Requirements Using Splices (TORUS), a novel traceability framework for the development of large-scale safety-critical CPS. TORUS introduces splices , autonomous graph-based data structures that automatically create and manage trace links between requirements and components through the inevitable changes that occur during system development. The formal, graph-based structure of TORUS lends itself well to the development of sophisticated algorithms to automate the extraction of useful traceability information such as historical records and metrics for requirements coverage and component coupling. By capturing not only the current state of the system but also historical information, TORUS allows project teams to see a much richer view of the system and its artifacts. We apply TORUS to the development of a protection system for smart grid substations. In addition, through a number of experiments in splice creation, modification, and application of automated algorithms, we show that TORUS scales easily to large systems containing hundreds of thousands of requirements and system components and millions of possible trace links.

Design and Realization of a Stepper Motor Driver with PLC

The paper is giving a simple and economical solution but with high performance for programming and controlling of Stepper Motor ( SM ) by using an industrial Programmable Logic Controller ( PLC ). PLC is advanced as a control device without any interface or drive circuits, thereby reducing the number of circuit components lowering the cost and improving the whole reliability of the system. SM is precise and accurate in creating discrete stationary angular revolutions, and for this characteristic, it has been used in numerous applications. The interested applications its usage in Robotic Arm Controller ( RAC ). The proposed control algorithm involves the control of SM speed, direction ( both clockwise &amp; counter-clockwise ), and the number of step of rotation. The SM that is proposed to be controlled in experimental is four phase ( 6 wires ), with hybrid coil category, unipolar connection of stator winding, 24V rated voltage, 1.5A rated current, and it has step angle equal to 1.8º. Function Block Diagram ( FBD ) program design language is used to realize the proposed PLC control program for SM. Wave Stepping Excitation Method ( WSEM ) was employed for driving the SM.

The effects of vest type dynamic elastomeric fabric orthosis on sitting balance and gross manual dexterity in children with cerebral palsy: a single-blinded randomised controlled study*

Purpose: To evaluate the effects of vest type dynamic elastomeric fabric orthosis on posture and balance during sitting and gross manual dexterity and to compare the efficacy of daily wearing time of 2 h versus 6 h.Method: Twenty-four children with cerebral palsy (CP) aged 3–9 years with GMFCS levels III and IV were randomised to either of three groups: (i) a control group who received only conventional exercise therapy, (ii) dynamic elastomeric fabric orthosis 2 h group who wore the orthosis for 2 h during therapy and dynamic elastomeric fabric orthosis 6 h group who wore the orthosis for 4 h in addition to the 2 h of wear along with therapy during hospital inpatient stay for 2 weeks. Children continued to use dynamic elastomeric fabric orthosis during the post-discharge period. The primary outcome measure was the Sitting Assessment Scale. The secondary outcome measurements were the sitting dimension of Gross Motor Function Measure, Box and Block Test and Parent Satisfaction Survey. Assessments were made before treatment, at post-treatment, at 1-month post-treatment, and at 3-months post-treatment. Sitting Assessment Scale and Box and Block Test were also assessed when immediately after wearing the orthosis. This trial is registered with Clinicaltrials.gov, under number NCT03191552.Results: All groups showed similar improvements except the control group which showed less improvement in Sitting Assessment Scale scores compared to the dynamic elastomeric fabric orthosis groups. Dynamic elastomeric fabric orthosis groups showed greater improvements compared to the control group in the Sitting Assessment Scale but not in the sitting dimension of Gross Motor Function Measure and Box and Block Test at post-treatment, at 1-month post-treatment and at 3-months post-treatment. When the dynamic elastomeric fabric orthosis groups (2 h versus 6 h) were compared, there were no significant differences in any of the assessments. The Sitting Assessment Scale and Box and Block Test scores also improved immediately after the patients put on the orthosis. At 1-month post-treatment, parents of children in the control group reported less satisfaction than parents of the children in dynamic elastomeric fabric orthosis groups.Conclusions: Dynamic elastomeric fabric orthosis vest has an immediate effect on the sitting balance and gross manual dexterity. It also provides improvements in posture and balance during sitting. Wearing dynamic elastomeric fabric orthosis vest for 2 h during therapy is as much effective as wearing it for 6 h in children with CP in addition to therapy to improve sitting balance.Implications for rehabilitationDynamic elastomeric fabric orthosis vest provides improvements in sitting balance when used in addition to conventional therapy in children with cerebral palsy.Wearing dynamic elastomeric fabric orthosis for 2 h and wearing dynamic elastomeric fabric orthosis vest for 6 h resulted in similar clinical outcomes.Dynamic elastomeric fabric orthosis vest has an immediate effect on sitting balance and gross manual dexterity in children with cerebral palsy.

Gold nanorods-based thermosensitive hydrogel produces selective long-lasting regional anesthesia triggered by photothermal activation of Transient Receptor Potential Vanilloid Type-1 channels.

Long-lasting regional anesthesia and selective sensory block are useful in post-operative analgesia and treatment of pathological pain. Previous studies have demonstrated that activation of TRPV1 (Transient Receptor Potential Vanilloid Type-1) channels facilitated the potency of QX-314 for selective long-lasting regional anesthesia in vivo. Hydrogel is a solid jelly-like material covering a wide range of properties from soft and weak to hard and tough. Gold nanorods are nanoparticles, which can be used for hyperthermia by exposure to near-infrared radiation. We fabricated a gold nanorods and QX-314 containing hydrogel. The molecular weight of hydrogel was adjusted to achieve a targeted phase transition temperature. Gold nanorods with a desired photothermal conversion efficacy and QX-314 were mixed with hydrogel to produce a gold nanorods-QX-314/hydrogel nanocomposite. A rat model of sciatic nerve block was applied to evaluate the regional anesthetic effect of the gold nanorods-QX-314/hydrogel nanocomposite. Upon exposure to near-infrared irradiation, the gold nanorods-QX-314/hydrogel nanocomposite activated TRPV1 channels through photothermal conversion and release of QX-314 at the same time. The gold nanorods and QX-314 loaded hydrogel exhibited a long-lasting regional anesthetic effect with selective sensory function block. Sensory block duration of the nanocomposite was significantly longer than of 1% lidocaine (90.0 ± 12.2 vs. 37.5 ± 12.5 min, P < 0.01). Motor block by the nanocomposite was observed for only 40% of rats with significantly shorter duration than its sensory block (42.5 ± 17.1 vs. 90.0 ± 12.2 min, P < 0.01). The gold nanorods-QX-314/hydrogel nanocomposite can produce a selective long-lasing regional anesthetic effect in a rat model of sciatic nerve block.

O 075 – Exploration of the role of forearm muscles during activities of daily living

Instrumented gloves are motion capture systems that are widely used due to the simplicity of the setup required and the absence of occlusion problems when manipulating objects. Nevertheless, the effect of their use on manipulation capabilities has not been studied to date. Therefore, the aim of this work is to quantify the effect of wearing CyberGlove instrumented gloves on these capabilities when different levels of precision are required. Thirty healthy subjects were asked to perform three standardised dexterity tests twice: bare-handed and wearing instrumented gloves. The tests were the Sollerman Hand Function Test (to evaluate capability of performing activities of daily living), the Box and Block Test (to evaluate gross motor skills) and the Purdue Pegboard Test (to evaluate fine motor skills). Scores obtained in the test evaluating fine motor skills decreased by an average of 29% when wearing gloves, while scores obtained on those evaluating gross motor skills and capability to perform activities of daily living were reduced by an average of 8% and 3%, respectively. The use of instrumented gloves to record hand kinematics is only recommended when performing tasks requiring medium and gross motor skills.