Methods For Integration Of Systems Research Articles

An Overview of Digital Engineering Methods for Platform Integration of Power and Energy Systems

US Navy ships, and combatant ships in particular, have requirements for integrated systems that are designed and configured for operational efficiency, redundancy, and survivability. Mission systems today and in the future will not always come with their own energy and many may, at times, require extreme pulse power loads. In addition, the migration away from fossil fuels to hybrid systems with energy storage, or the requirements for autonomous platforms, is challenging our ability to design platforms for these systems. Understanding the interdependencies between components, the systems they support, and the energy domains they are member of is a critical ontological design requirement. This paper will address how we applied digital engineering principles and computer science to the design of ontologies that allow for the modeling of complex operational systems riding on the same shipboard energy network. This system network must support varying levels of detail needed during design while at the same time understanding the impacts of that design on ship system operations and their energy loads over time.

Evaluation and implementation of Lie group integration methods for rigid multibody systems

AbstractAs commonly known, standard time integration of the kinematic equations of rigid bodies modeled with three rotation parameters is infeasible due to singular points. Common workarounds are reparameterization strategies or Euler parameters. Both approaches typically vary in accuracy depending on the choice of rotation parameters. To efficiently compute different kinds of multibody systems, one aims at simulation results and performance that are independent of the type of rotation parameters. As a clear advantage, Lie group integration methods are rotation parameter independent. However, few studies have addressed whether Lie group integration methods are more accurate and efficient compared to conventional formulations based on Euler parameters or Euler angles. In this paper, we close this gap using the $\mathbb{R}^{3}\times SO(3)$ R 3 × S O ( 3 ) Lie group formulation and several typical rigid multibody systems. It is shown that explicit Lie group integration methods outperform the conventional formulations in terms of accuracy. However, it turns out that the conventional Euler parameter-based formulation is the most accurate one in the case of implicit integration, while the Lie group integration method is computationally the more efficient one. It also turns out that Lie group integration methods can be implemented at almost no extra cost in an existing multibody simulation code if the Lie group method used to describe the configuration of a body is chosen accordingly.

Study on the Application of a Multi-Energy Complementary Distributed Energy System Integrating Waste Heat and Surplus Electricity for Hydrogen Production

To improve the recovery of waste heat and avoid the problem of abandoning wind and solar energy, a multi-energy complementary distributed energy system (MECDES) is proposed, integrating waste heat and surplus electricity for hydrogen storage. The system comprises a combined cooling, heating, and power (CCHP) system with a gas engine (GE), solar and wind power generation, and miniaturized natural gas hydrogen production equipment (MNGHPE). In this novel system, the GE’s waste heat is recycled as water vapor for hydrogen production in the waste heat boiler, while surplus electricity from renewable sources powers the MNGHPE. A mathematical model was developed to simulate hydrogen production in three building types: offices, hotels, and hospitals. Simulation results demonstrate the system’s ability to store waste heat and surplus electricity as hydrogen, thereby providing economic benefit, energy savings, and carbon reduction. Compared with traditional energy supply methods, the integrated system achieves maximum energy savings and carbon emission reduction in office buildings, with an annual primary energy reduction rate of 49.42–85.10% and an annual carbon emission reduction rate of 34.88–47.00%. The hydrogen production’s profit rate is approximately 70%. If the produced hydrogen is supplied to building through a hydrogen fuel cell, the primary energy reduction rate is further decreased by 2.86–3.04%, and the carbon emission reduction rate is further decreased by 12.67–14.26%. This research solves the problem of waste heat and surplus energy in MECDESs by the method of hydrogen storage and system integration. The economic benefits, energy savings, and carbon reduction effects of different building types and different energy allocation scenarios were compared, as well as the profitability of hydrogen production and the factors affecting it. This has a positive technical guidance role for the practical application of MECDESs.

Research on system integration and control methods of an apple-picking robot in unstructured environment

PurposeThe purpose of this article is to solve the issue that apple-picking robots are easily interfered by branches or other apples near the target apple in an unstructured environment, leading to grasping failure and apple damage.Design/methodology/approachThis study introduces the system units of the apple-picking robot prototype, proposes a method to determine the apple-picking direction via 3D point cloud data and optimizes the path planning method according to the calculated picking direction.FindingsAfter the field experiments, the average deviation of the calculated picking direction from the desired angle was 11.81°, the apple picking success rate was 82% and the picking cycle was 11.1 s.Originality/valueThis paper describes a picking control method for an apple-picking robot that can improve the success and reliability of picking in an unstructured environment and provides a basis for automated and mechanized picking in the future.

A kind of numerical model combined with genetic algorithm and back propagation neural network for creep-fatigue life prediction and optimization of double-layered annulus metal hydride reactor and verification of ASME-NH code

The safety and stability of metal hydride reactor (MHR) structure are significantly important for normal operations of hydrogen isotope storage and supply system. Moreover, considering that the experiments of studying the fatigue and creep properties of MHR structure are always time, money, difficulty and energy consuming. To further improve the service life of MHR as well as lower the failure risk, this paper proposes a system integration method based on ASME code validation, which combines genetic algorithm (GA) and back propagation neural network (BPNN) for rapid assessment of creep-fatigue life (CFL) and optimal design of structural parameters. First, numerical simulation is applied to perform thermal-mechanical coupled finite element analysis and verified by ASME code. Then, parametric sensitivity analysis and experimental design of parameter-based training set based on Taguchi method were performed, and response values are obtained from physical models combined with numerical simulations. Finally, a parametric optimization procedure combining BPNN and GA is developed based on the training data. In the workflow, parametric data flow is passed through the experimental design, numerical simulation, prediction and optimization processes. The results show that the proposed BPNN proxy model based on ASME code validation has good performance in predicting the life of MHR. Based on this, the life of the MHR is improved by 8% compared to the reference sample.

A new method for finding global solutions to Synge’s electromagnetic problem

Synge’s problem consists in determining the dynamics of two point electrical charges interacting through their electromagnetic fields, without taking into account the radiation terms due to the self-forces in each charge. We discuss how this problem is related to the question on to establish initial conditions for the electromagnetic fields that are compatible with the two point charges system in isolation, that is, the charges are free from the action of external forces. This problem stems from the existence of inter-temporal constraints for the charges trajectories, which implies that the relativistic Newton equations for the charges is not a system of ordinary differential equations (ODEs), but rather a system of functional differential equations (FDEs). We developed a new method to obtain global solutions that satisfies this system of FDEs and a given initial condition for the charges positions and velocities. This method allows the construction of a recursive numerical algorithm that only use integration methods for ODEs systems. Finally, we apply this algorithm to obtain numerical approximations for the quasi-circular solutions that are predicted in Synge’s problem.

Analysis of information systems integration methods

The integration of information systems in a single circuit is of high relevance for the activities of economic entities, since it ensures the effective functioning of the organization's information system, contributes to its competitiveness. In the context of digital transformation, business managers and services responsible for information support are forced to look for optimal methods and technologies for information systems integration. The article discusses modern methods used in the componential integration into a single information space of economic objects. Examples of integration methods’ application of information systems in the Republic of Uzbekistan are given. It is noted that the choice of the most effective integration method depends on the organization’s needs, resources and existing infrastructure.

Rosenbrock-W methods for stochastic Galerkin systems

The stochastic Galerkin approach is a widely used method for quantifying uncertainty in dynamical systems. A polynomial chaos expansion of physical variables is used to represent uncertainty. Thus the evolution equations for the dynamics of physical quantities are replaced by evolution equations for the polynomial chaos coefficients. The dimension of the stochastic Galerkin system is m times larger than the dimension of the original physical system, where m is the number of polynomial chaos coefficients. The cost of implicit time integration methods, required for stiff dynamical systems, increases considerably, for example, by a factor m3 when direct linear solvers are used.This work studies efficient implicit methods for the time integration of stiff stochastic Galerkin systems consisting of ordinary differential equations. Linearly-implicit Rosenbrock–Wanner schemes are considered. A block-diagonal approximation of the Jacobian of the stochastic Galerkin system is employed, where the diagonal blocks are the Jacobian of the physical system, evaluated at the mean solution value. We perform a theoretical study of numerical stability for this approximation, using a stochastic extension of the Dahlquist test equation, and propose a concept of linear stochastic Galerkin stability. A rigorous analysis is done for methods of order one and two. A third-order scheme is designed to investigate the stability properties by numerical experiments. Numerical results confirm the theoretical findings.

Managing engineering challenges in the design and implementation of eco-friendly residential structures

The planning and execution of eco-friendly housing face technical hurdles, particularly in regions like Jordan. This study aims to address primary obstacles in overseeing eco-friendly residential buildings in Jordan. The research highlights the unique ecological, weather-related, and financial factors impacting these difficulties. Various technical issues throughout the eco-friendly building's life cycle, including site selection, design, energy systems integration, water conservation, and construction methods, are recognized. Furthermore, upgrading existing residences to eco-friendly standards is explored. Drawing from these challenges, the study proposes suggestions for handling technical hindrances in Jordan's eco-friendly housing. Recommendations encompass technological progress, policy frameworks, skill enhancement, and awareness initiatives to advance sustainable construction. By managing these challenges, it's possible to boost environmental efficiency, energy effectiveness, and overall sustainability of residential structures, aligning with Jordan's goals of reducing carbon emissions and promoting an ecologically conscious economy.

A multi-physics system integration and modeling method for piezoelectric wave energy harvester

The multiphysics system integration and modeling method, including hydrodynamic, kinematic, and electromechanical models, were developed. A one-way plucking-driven piezoelectric wave energy harvester (OPD-PWEH) was also developed; it consists of a floating cylindrical buoy, a frequency up-conversion mechanism based on a one-way bearing, and a piezoelectric component based on an array of piezoelectric bulk composite cantilever beams. The one-way bearing converts the repetitive clockwise and counterclockwise rotary motion of the input shaft into a single-directional clockwise rotary motion of the output shaft. The OPD-PWEH was tested in a wave flume under wave amplitudes of 50, 37.5, and 25 mm and wave periods of 1.0, 1.5, and 2.0 s. The experimental results showed that the RMS voltage and average power were 4.47 V and 0.4 mW, respectively, and they were obtained at 50 mm wave amplitude and 1 s wave period.

Design of Cascaded Multilevel Inverter and Enhanced MPPT Method for Large-Scale Photovoltaic System Integration

The key goal of this effort is to develop an efficient control system for a three-phase cascaded H-bridge multilevel inverter powered by the photovoltaic (PV) system. The power for the system is generated through the use of PV modules, which serve as DC inputs for the cascaded H-bridge multilevel inverter. The authors aim to achieve a nearly sinusoidal signal at the voltage level and are specifically focused on minimizing the total harmonic distortion (THD) to the smallest possible value. Hence, an advanced N-level space vector modulation (SVM) is developed to ensure an appropriate control for the cascaded inverter. The aim is to design an effective control strategy to increase inverter efficacy and, thus, supply the best output quality. In addition, a robust approach to the maximum power point (MPP) tracking (MPPT) technique is developed based on an adaptive perturb and observe (P&O) algorithm to ensure superior tracking of the MPP. The developed algorithm eliminates 90% of the power curve area in the search space process and only maintains 10% of the area that includes the MPP. Each PV system employs its own improved MPPT control. The numerical results confirm that the enhanced P&O algorithm attains a precise response with superior efficiency and a fast response under the fast alteration of environmental conditions. Hence, the energy loss is reduced. The simulation results validate the effectiveness of this study, highlighting the high efficiency of the control strategy and the enhanced performance of the proposed scheme with lesser THD values.

Investigations on System Integration Method and Optimum Design Method of Electro-Mechanical Actuator System

With technological advances and industrial upgrading, high-performance equipment has put higher demands on the performance of electro-mechanical actuators. With a view to making electro-mechanical actuators more reliable and integrated, firstly, an integrated electro-mechanical actuator module (IEMM) with multiple structural forms was proposed in this paper, and a comparative analysis was performed on the characteristics of different transmission schemes. Then, the feasibility of manufacturing the IEMM’s main bearing components using Carbon Fiber Reinforced Polymer (CFRP) with higher specific stiffness, specific modulus and specific strength was demonstrated by finite element simulation (FEA) software, in a bid to further reduce the weight of the IEMM. Next, a parameter estimation model, a heating power calculation model, and a thermal resistance calculation model were built, so that there is no need to rebuild the whole system model under different demand indexes. On this basis, a multi-objective optimization design model was built with light weight, low power loss, and high level of integration as optimization aims to achieve better comprehensive performance in the early design phase of the IEMM system. However, IEMM’s higher level of integration and its shell made of CFRP with a thermal conductivity of less than 5 W/m°C posed a challenge to the heat dissipation of the motor stator. Therefore, a thermal network model needs to be created in AMESim to evaluate the temperature of IEMM’s parts and components under different working conditions. Finally, the process of IEMM performance optimization design was described and improved, and performance optimization design was conducted by taking one of IEMM’s transmission schemes as an example.

Achievements and prospects of creating systems for determining the orientation of small space satellite

Advances in the development of small satellites, combined with the availability of low-cost launches, have led to an increase in the number of space flights. As space becomes more accessible than ever before, new and innovative missions are emerging.
 A set of achievements in the field of automatic systems, control system devices, computer systems, control system executive bodies, methods and methods of control system integration, which made it possible to create multi-purpose, multi-mode systems with a long active life cycle, systems with maximum autonomy and automation of control processes, is shown.
 This article presents the achievements and prospects of spacecraft control systems over the past three decades. The problematic issues of increasing the accuracy of orientation and stabilization are considered.

Multirate Exponential Rosenbrock Methods

In this paper we propose a novel class of methods for high order accurate integration of multirate systems of ordinary differential equation initial-value problems. The proposed methods construct multirate schemes by approximating the action of matrix $\varphi$-functions within explicit exponential Rosenbrock (ExpRB) methods, thereby called Multirate Exponential Rosenbrock (MERB) methods. They consist of the solution to a sequence of modified "fast" initial-value problems, that may themselves be approximated through subcycling any desired IVP solver. In addition to proving how to construct MERB methods from certain classes of ExpRB methods, we provide rigorous convergence analysis of these methods and derive efficient MERB schemes of orders two through six (the highest order ever constructed infinitesimal multirate methods). We then present numerical simulations to confirm these theoretical convergence rates, and to compare the efficiency of MERB methods against other recently-introduced high order multirate methods.

Two Methods for the Implicit Integration of Stiff Reaction Systems

Abstract We present two methods for the implicit integration of nonlinear stiff systems. Direct application of the Newton method to backward Euler discretization of such systems may diverge. We observe that the solution is recovered by smoothing out certain eigenvalues in the Jacobian matrix. To this end, we introduce a solution-dependent matrix-weighted combination of backward and forward Euler methods. The weight is tuned on each Newton iteration to reproduce the solution with an exponential integrator, whereby a weight function for smoothing eigenvalues is obtained. We apply the proposed techniques, namely quasi-Newton backward Euler and matrix-weighted Euler, to several stiff systems, including Lotka–Volterra, Van der Pol’s, and a blood coagulation cascade.

A new class of G(ϵ)-symplectic general linear methods

A new class of G(ϵ)-symplectic general linear methods for numerical integration of Hamiltonian systems of differential equations is described. Order conditions for these methods are derived using Albrecht approach and the construction of G(ϵ)-symplectic method is described based on solving minimization problems with nonlinear inequality constrains. Examples of methods up to the order four are presented. Numerical experiments confirm that these methods achieve the expected order of accuracy and that they approximately preserve Hamiltonians of differential systems.

Control system integration methods to maintain the position and speed of the robot in spatial forbidden areas

Control system integration methods to maintain the position and speed of the robot in spatial forbidden areas

Integral Fire Protection Analysis of Complex Spatial Steel Structure Based on Optimized Gaussian Transformation Model.

The rapid development of complex space steel structure buildings has brought new challenges to structural fire protection analysis and design. On the basis of analyzing the deficiencies of structural fire protection design in existing normative and performance-based design methods and based on the knowledge and research results of fire science, structural engineering, computer simulation, and other disciplines, this paper proposes an improved Gaussian transformation model and applied it to the overall fire performance analysis of this complex space steel structure. The proposed model is based on theoretical research and practical application of the simulation and analysis of the overall fire performance of complex spatial buildings. The coupled analysis model and system integration method of spatial overall structure fire and structure are established. The improved Gaussian transformation model is used to propose the integrity of complex spatial structures. It is a system analysis model for fire analysis. The experimental results show that the designed algorithm model can effectively realize the overall fire performance analysis of complex spatial steel structures and can provide a useful reference for China's building fire protection research, building fire protection design, fire rescue, emergency plan formulation, and other engineering practical applications.

Small-signal stability analysis of implicit integration methods for power systems with delays

The paper focuses on the accuracy and stability of implicit numerical methods when utilized for the Time Domain Integration (TDI) of power systems with inclusion of time delays. In particular, a small-disturbance analysis technique is proposed to evaluate the numerical distortion that TDI methods induce to the dynamic modes of power systems modeled as Delay Differential Algebraic Equations (DDAEs). The case study illustrates the features of the proposed technique through simulations conducted using the IEEE 14-bus test system, and considering three examples of implicit integration methods, namely Backward Euler Method (BEM), Implicit Trapezoidal Method (ITM), and 2-stage Radau IIA.

Second Derivative Block Hybrid Methods for the Numerical Integration of Differential Systems

The second derivative block hybrid method for the continuous integration of differential systems within the interval of integration was derived. The second derivative block hybrid method maintained the stability properties of the Runge–Kutta methods suitable for solving stiff differential systems. The lack of such stability properties makes the continuous solution not reliable, especially in solving large stiff differential systems. We derive these methods by using one intermediate off-grid point in between the familiar grid points for continuous solution within the interval of integration. The new family had a high accuracy, non-overlapping piecewise continuous solution with very low error constants and converged under the suitable conditions of stability and consistency. The results of computational experiments are presented to demonstrate the efficiency and usefulness of the methods, which also indicate that the block hybrid methods are competitive with some strong stability stiff integrators.