The article studies the possibility of using the LabVIEW programming environment to develop real-time dynamic models of continuous processes. The principle of data flow implemented in the LabVIEW ...environment makes it possible to abandon the direct solution of differential equations when developing a dynamic simulation of a technological object. It is proposed to present the simulation object as a set of dynamic elements, the main of which is the integrating element. The block diagrams of the proportional, integrating, inertial, and delay elements are given. The applicability of the LabVIEW platform for modeling continuous processes is demonstrated on the example of a simple heat exchanger model, which hydrodynamic flows structure corresponds to the ideal mixing model. The schematic and block diagrams of the developed model are given. In order to test the heat exchanger model, a numerical experiment was carried out in static and dynamic modes. The results of testing of the model confirmed its consistency, sensitivity and validity, which are signs of adequacy.
Developing autonomous vehicles (AVs) that operate in diverse and demanding environments is a difficult challenge. Two fundamental tools that can accelerate this process are testing an AV in diverse ...simulated environments and identifying core system weaknesses. While most efforts focus on improving these tools for on-road AVs, this letter focuses on an analogous set of tools for off-road AVs. A method called Black-Box Adversarially Compounding Regret Through Evolution (BACRE) is proposed for identifying adversarial scenarios using an evolutionary algorithm guided by a novel regret-based metric for general navigation tasks. A black-box approach is often preferable when system complexity can be diverse, like with off-road AVs, and when whole-system testing is required. A custom simulation platform is also provided to assist with the automated testing of AVs in diverse, unstructured environments. Numerical experiments demonstrate that BACRE's evolutionary process gradually increases scenario complexity to degrade vehicle performance (an effective and explainable process that comparable methods cannot achieve). Consequently, BACRE can streamline AV development by finding weaknesses at any development stage.
While using security tools to resolve security defects, software developers must apply considerable effort. Success depends on a developer's ability to interact with tools, ask the right questions, ...and make strategic decisions. To build better security tools and subsequently help developers resolve defects more accurately and efficiently, we studied the defect resolution process—from the questions developers ask to their strategies for answering them. In this paper, we report on an exploratory study with novice and experienced software developers. We equipped them with Find Security Bugs, a security-oriented static analysis tool, and observed their interactions with security vulnerabilities in an open-source system that they had previously contributed to. We found that they asked questions not only about security vulnerabilities, associated attacks, and fixes, but also questions about the software itself, the social ecosystem that built the software, and related resources and tools. We describe the strategic successes and failures we observed and how future tools can leverage our findings to encourage better strategies.
Two powerful and versatile code packages (Agros Suite and Ārtap) are presented for design and optimization of technical devices and systems. Agros Suite represents an environment for numerical ...solution of systems consisting of partial differential equations (PDEs) of the second order by a higher-order finite element method with a lot of further advanced features such as full adaptivity and selected optimization techniques. Ārtap is a robust design optimization toolbox that provides a simple and efficient programming environment for a wide-range of optimization methods, integrated and external PDE solvers and well-established machine learning tools. Both packages are described in a sufficient detail and their power is illustrated with solution of three problems from the domain of technical sciences.
There has recently been a renewed interest in integrating programming into the curriculum of primary education, partly due to the availability of the visual programming environment (VPE) designed for ...educational purposes. While substantial progress on exploring the potential benefits of VPE has been achieved, much remains to be done to understand students' acceptance of VPE and whether gender difference plays a role in their acceptance. This study was thus designed to extend the technology acceptance model to identify determinants influencing boys' and girls' behavioural intention to use VPE in the primary school context. It used a mixed method approach to evaluate the proposed model using questionnaire and interview data collected from 431 students (296 boys and 135 girls) in 38 primary schools. Among boys and girls, computer self-efficacy is shown to be the external factor significantly influencing both perceived usefulness and perceived ease of use of VPE, while attitude towards VPE is found to have a significant effect on behavioural intention to use VPE. In addition, gender differences are found in the impact of social influence and external encouragement on students' perceptions towards VPE, and also in the impact of students' perceptions towards VPE on their behavioural intention to use it. Based on the findings, several recommendations are made to encourage primary students to use VPE for programming.
•There is a lack of studies exploring gender and acceptance of VPE in primary schools.•Computer self-efficacy has the largest effect on students' perceptions of VPE.•Social influence tends to impact on boys' perceived usefulness of VPE.•External encouragement tends to impact on girls' perceived usefulness of VPE.•Gender differences in the determinants of behavioural intention to use VPE are found.
The results of creating a hardware-software complex based on a precision LCR Agilent E4980A meter and a measuring cell 16454A using the LabVIEW programming environment for automated measurements of ...the frequency dependences of materials permeability are presented. Spectra of the real and imaginary parts of the magnetic permeability of ferrimagnets were obtained in the frequency range from 2 kHz to 2 MHz. A comparison of the measurement results with known data is performed.
Abstract
Modern manufacturing systems consist of a sequence of robotic systems, such as robotic cells, which are widely used in the industry. As they become commonplace and play important roles in ...modern industrial production, efficient modelling and use of robotic cells become a necessity. Robotization brings many measurable benefits. It enables effective utilization of both human resources and the possessed machine park and thus contributing to the improvement of product quality and efficiency. Industrial robots not only increase the growth of productivity, by replacing man in monotonous works, requiring enormous, not achievable for human precision but above all ensure the accuracy and repeatability of the product quality. Appropriate design and modelling of robotic manufacturing systems are crucial in the efficient integration of work cell components and proper maintenance of robotic production systems. Therefore, new solutions for programming environments in industrial applications are sought which not only allow reprogramming of industrial robots but also enable the virtual design of new production lines, which in turn allows the faster introduction of higher quality products. This article presents the modelling and programming of robotic work cells in the Siemens Process Simulate environment.
The aim of this document is to present the topic of operational optimization in District Heating (DH) systems, with special focus on different kinds of thermal energy storage. An optimization ...solution based on solving multiple Mixed Integer Linear Programming (MILP) problems has been proposed and implemented in the R programming environment.
The operational optimization in a DH system, especially if this system is supplied from a combined heat and power (CHP) plant, is a difficult and complicated task. Finding a global financial optimum requires considering long periods of time and including thermal energy storage possibilities into consideration. There are three important solutions for thermal energy storage: hot water tanks, utilization of thermal inertia of the network itself and utilization of thermal inertia of buildings. Each of these solutions has its advantages and disadvantages, and they can be combined to reach the maximum flexibility at lowest cost. However, modeling of operation with all of the thermal energy storage possibilities in place is a complicated task, since they influence the transient behavior of the network in different ways, and affect each other. On the other hand, optimal planning of heat production can be done only if simple and robust simulation models are available. Proposed solution allows simulation of three kinds of thermal energy storage, with their specific transient behaviors and interactions, at the same time keeping the model simple and ready to be used with a MILP solver. An iterative approach has been applied to non-linear phenomena, which allows solving a non-linear problem by multiple MILP optimizations. It has been successfully implemented in the “R” programming environment and tested on a simple example. The results can prove useful for DH system operators in the near future.
•Mathematical model for operational optimization in district heating is proposed.•Combined heat and power generation with thermal energy storage is simulated.•Storage in hot water tank, network pipelines and buildings' inertia is considered.•Example of heat load shifting to balance the electricity production is demonstrated.•Effects of utilization of particular thermal energy storage solutions are presented.
Evaluating the in situ concrete compressive strength by means of cores cut from hardened concrete is acknowledged as the most ordinary method, however, it is very difficult to predict the compressive ...strength of concrete since it is affected by many factors such as different mix designs, methods of mixing, curing conditions, compaction, etc. In this paper, considering the experimental results, three different models of multiple linear regression model （MLR）, artificial neural network （ANN）, and adaptive neuro-fuzzy inference system （ANFIS） are established, trained, and tested within the Matlab programming environment for predicting the 28 days compressive strength of concrete with 173 different mix designs. Finally, these three models are compared with each other and resulted in the fact that ANN and ANFIS models enables us to reliably evaluate the compressive strength of concrete with different mix designs, however, multiple linear regression model is not feasible enough in this area because of nonlinear relationship between the concrete mix parameters. Finally, the sensitivity analysis （SA） for two different sets of parameters on the concrete compressive strength prediction are carried out.
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