Hierarchical Block Diagrams Research Articles

Increasing the construction production efficiency based on the use of cyber-physical systems and technologies

Objective: The article proposes a classification of cyber-physical systems and technologies at the stages of the life cycle of a construction project, considers an algorithm for choosing these technologies depending on the effectiveness of the project. Theoretical framework: The study is based on the review of publications in international scientific journals, methodological literature on the topic of the use of digital tools in construction. The experience of different countries in the application of cyber-physical systems and technologies in construction was represented. Method: The study was conducted based on materials published in open sources, including scientific articles, reports, regulatory documents. In addition, the study used the experience of several companies operating in the construction industry. Results and conclusion: The main approaches to planning construction projects at the stage of the life cycle are studied. Approaches to the formation of a graphical hierarchical block diagram of a simulation model, consisting of different levels of nesting, are proposed. The results may be of interest to manufacturing companies that decide to implement digital technologies in construction, as well as individual scientists who study the problem of increasing the efficiency of production organization at the stages of the construction projects life cycles. Implications of the research: The results of the study can be used by construction companies when planning the choice of cyber-physical systems and technologies at the stages of the life cycle of construction objects Originality/value: The authors propose an approach that allows choosing tools for designing and building objects using cyber-physical systems and technologies at the stages of the life cycle. A hierarchical block diagram of the simulation model is proposed, which contains more than a dozen child diagrams that combine several hundred smaller typical modules.

Design and implementation of a dynamic system simulation framework for plasma control system verification platform

The plasma control system (PCS) is a key part in tokamak operations, which requires test and verification. Dynamic system simulation tools have been widely utilized to build a simulation environment to verify the design of plasma control systems as well as other parts of tokamak systems under various operation scenarios, save the time and cost of real discharges, improve the efficiency of deployment and reduce risks. To provide a simulation platform based on open-source software as part of the infrastructure of the PCS-VP (Verification Platform) of the China Fusion Engineering Test Reactor (CFETR), a framework named DSSim (Dynamic System Simulation) is proposed. It is an environment for dynamic system simulation based on Python, which enables users to build and simulate hierarchical block diagram models with interconnected systems that corresponds to different dynamic systems. Solutions for special tasks that helps improve the accuracy of simulation like flattening the model hierarchy, scheduling system execution order and solving continuous systems are implemented and will be automatically invoked in different phases of simulation. A GUI client with the DSSim framework built in is developed to allow for constructing and simulating block diagram models in a more user-friendly way. A model of the vacuum field system of the Experimental and Advanced Superconducting Tokamak (EAST) is built and simulated with DSSim and the result is compared with that of the same model in MATLAB/Simulink to test the framework's precision and usability.

Structure of the information management system of cereal crops cultivation

The problems of constructing and implementing the structure of the information management system (IMS) for the cultivation of grain crops based on the optimization of the choice of agricultural technologies in view of the methods of the management theory, system and compartmental approaches are considered. The objects of management are soil, a cultivated crop and ecology of the agricultural landscape area used. It is concluded that the IMS belongs to the class of adaptive control systems with prediction by a multidimensional dynamic stochastic object. A new quality of the management system, which significantly determines its structure, is shown, namely the presence of a control loop for maintaining soil fertility and ecology in crop rotation and a control loop for the agrocenosis of the crop. A hierarchical block diagram of the object management system with forecasting is proposed, which implements functional transformations of the information flow in the IMS. As a criterion for choosing an alternative agricultural technology, environmental and economic efficiency was used, modified in view of the management goals and the composition of the machine and tractor fleet. The analytical description of the processes of the agrobiosystem at the modern level is based on the compartmental approach with the description of phenomena in the form of differential equations. The content of the compartment describes the process of energy and mass transfer in the system: soil – vegetation cover – ground layer of the air based on functional (theoretical) dynamic simulation. Based on the results of the information review, the possibility of implementation of such a management system has not been currently identified. The use of empirical simulation models in the IMS is unacceptable, since a change in a crop or natural-climatic zone will require the development of a new empirical model. The systems for simulating biophysical processes WOFOST, DSSAT, DSSAT Cropping System (CSM), APSIM and AGROTOOL, using methods of functional dynamic simulation within the framework of the compartmental approach, have been analyzed. The developed IMS structure using the AGROTOOL crop productivity model is implemented on condition that new modules of compartments are created.

PowerDEVS: a tool for hybrid system modeling and real-time simulation

In this paper we introduce a general-purpose software tool for discrete event system specification (DEVS) modeling and simulation oriented to the simulation of hybrid systems. The environment, called PowerDEVS, allows atomic DEVS models to be defined in C++ language that can then be coupled graphically in hierarchical block diagrams to create more complex systems. The environment automatically translates the graphically coupled models into a C++ code which executes the simulation. A remarkable feature of PowerDEVS is the possibility to perform simulations under a real-time operating system (RTAI) synchronizing with a real-time clock, which permits the design and automatic implementation of synchronous and asynchronous digital controllers. Combined with its continuous system simulation library, PowerDEVS is also an efficient tool for real-time simulation of physical systems. Another feature is the interconnection between PowerDEVS and the numerical package Scilab. PowerDEVS simulations can make use of Scilab workspace variables and functions, and the results can be sent back to Scilab for further processing and data analysis. In addition to describing the main features of the software tool, the article also illustrates its use with some examples which show its simplicity and efficiency.

Modular code generation from synchronous block diagrams

We study modular, automatic code generation from hierarchical block diagrams with synchronous semantics. Such diagrams are the fundamental model behind widespread tools in the embedded software domain, such as Simulink and SCADE. Code is modular in the sense that it is generated for a given composite block independently from context (i.e., without knowing in which diagrams the block is to be used) and using minimal information about the internals of the block. In previous work, we have shown how modular code can be generated by computing a set of interface functions for each block and a set of dependencies between these functions that is exported along with the interface. We have also introduced a quantified notion of modularity in terms of the number of interface functions generated per block, and showed how to minimize this number, which is essential for scalability. Finally, we have exposed the fundamental trade-off between modularity and reusability (set of diagrams the block can be used in). In this paper we explore another trade-off: modularity vs. code size. We show that our previous technique, although it achieves maximal reusability and is optimal in terms of modularity, may result in code replication and therefore large code sizes, something often unacceptable in an embedded system context. We propose to remedy this by generating code with no replication, and show that this generally results in some loss of modularity. We show that optimizing modularity while maintaining maximal reusability and zero replication is an intractable problem (NP-complete). We also show that this problem can be solved using a simple iterative procedure that checks satisfiability of a sequence of propositional formulas. We report on a new prototype implementation and experimental results. The latter demonstrate the practical interest in our methods.

見張り支援ニューラルネットワークに関する基礎研究

It is an important solution to construct the lookout support neural network system for navigation at sea in order to raise a ship operation support level. This paper is concerned with a systematization of lookout function and with a picture recognition neural network system for a course and a type of ship estimation. The neural network topology is three-layered network, which consists of 36 units for input layer, 108 units for hidden layer and 26 units for output layer. Pictures of three-dimensional computer graphics which display ten kinds of ship design drawings are used for supervised training pictures. The summary of the results are shown below. (1) The lookout function which consists of a circumstances watch sub-function and a decision making sub-function is shown in a hierarchical block diagram. (2) Correct recognition rate of the course estimation and the type of ship estimation is 55.5% and 44.4% respectively. (3) Information of a navigational circumstance picture segmentation system building is obtained.

The Beacon Block-diagram Environment

BEACON is a Computer Aided Engineering environment which allows the user to graphically design a real time control system as a series of hierarchical block diagrams. The diagrams constitute a complete documentation of the designed system. These diagrams can thereafter be used to automatically generate both simulation and real-time computer code. BEACON has been used within the General Electric Company to generate production code since the first quarter of 1992. This paper will present the BEACON block-diagram editor, its graphical user interface, and its different modes of operation. The extensive hierarchical modeling capabilities of BEACON will be discussed.

Simulator for dynamical systems using graphics and equations for modeling

A prototype simulator for dynamical systems, called Hibliz (hierarchical block diagrams with information zooming), which explores some features of modern computer graphics, is presented. Hibliz supports hierarchical block diagrams to describe the model decomposition and interconnection structure. The user can scroll, pan, and zoom the block diagram continuously in real time. Zooming controls the amount of information displayed. Zooming in a block changes it from an annotated box to a representation showing internal structure with increasing detail. Since the block diagrams can be hierarchical, it is possible to make the description at each level simple and clear. Hibliz also simplifies model development by allowing submodels in the form or ordinary differential and algebraic equations rather than assignment statements for derivations and algebraic variables.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Gabriel: a design environment for DSP

Gabriel is a software system intended to manage the complete development of real-time digital signal processing (DSP) applications, from conception and experimentation to implementation in real-time hardware. It performs non-real-time simulations as well as code synthesis for real-time hardware. It is intended to ease code development for architectures that are not easy targets for conventional compilers, such as multiprocessor systems built with very high-performance microcoded DSPs. The system is designed to be retargetable in two ways. First, it can synthesize code for a variety of multi-DSP architectures where the user specifies the salient features of the architecture. Second, it can target different DSPs. The authors have concentrated on code generation for the Motorola DSP56001, although code generation for the AT&T DSP32 has been demonstrated. At the highest level, an algorithm is described using a hierarchical block diagram. At the lowest level, the user can either simulate the algorithm locally on the workstation, simulate the target architecture running the generated code, or download the code into hardware and run it in real time. Gabriel is capable of handling multiple sample rates, iteration, and recurrences. >