Methods For Integration Of Systems Research Articles

A New Class of High-Order Methods for Multirate Differential Equations

This work focuses on the development of a new class of high-order accurate methods for multirate time integration of systems of ordinary differential equations. The proposed methods are based on a specific subset of explicit one-step exponential integrators. More precisely, starting from an explicit exponential Runge--Kutta method of the appropriate form, we derive a multirate algorithm to approximate the action of the matrix exponential through the definition of modified “fast” initial-value problems. These fast problems may be solved using any viable solver, enabling multirate simulations through use of a subcycled method. Due to this structure, we name these multirate exponential Runge--Kutta (MERK) methods. In addition to showing how MERK methods may be derived, we provide rigorous convergence analysis, showing that for an overall method of order $p$, the fast problems corresponding to internal stages may be solved using a method of order $p-1$, while the final fast problem corresponding to the time-evolved solution must use a method of order $p$. Numerical simulations are then provided to demonstrate the convergence and efficiency of MERK methods with orders three through five on a series of multirate test problems.

A Low Complexity Design Framework for NFC-RFID Inductive Coupled Antennas

Inductive Wireless Power and Data Transfer (WPDT) technology has become a vital enabler to the globalisation of Internet of Things. Driven by an increasing demand for data within applications and by the need to reduce the devices footprint by transmitting data and power with the same antenna, power transfer efficiency has become a barrier to WPDT systems' performance. To overcome the limitations of power transfer efficiency, current research focuses on the design of efficient integrated circuits and does not consider the challenges of inductive antennas' design and system integration. Hence, current system integration methods used in industry to design receivers for WPDT applications still require expensive experimental benchmarking of antennas. This paper introduces a new framework for inductive WPDT systems integration that focuses on the design of inductive coils and tuning capacitances. First, this framework proposes a new planar rectangular coil inductance formula that achieves an average error of 11% based on the testing of one hundred of coils, which out performs the current state of the art. Then, based on a detailed electrical model of both transmitter and receiver of WPDT systems, our design framework computes the coils geometric parameters and tuning capacitances that will optimize the overall efficiency of the WPDT system. Unlike state of the art design approaches, the main advantage of this framework is that it does not require expensive benchmarking of inductive antennas to find the optimal antenna. Verification of our design framework was achieved through a comparative analysis for Very High Bit Rate 13.56 MHz RFID applications. Results indicate an improvement of more than 15% in overall system power transfer efficiency compared to current state of the art methods within a comparatively more cost effective framework. A sensitivity analysis provides an insight and practical guide to implications of manufacturing variances in component parameters.

Rao‐Blackwellised particle filtering for low‐cost encoder/INS/GNSS integrated vehicle navigation with wheel slipping

This study presents a Rao-Blackwellised particle filter (RBPF)-based encoder/inertial navigation system (INS)/global navigation satellite system (GNSS) integration method for improving the navigation performance of an autonomous land vehicle (ALV) with wheel slipping. In contrast to traditional integration methods, the proposed integration method introduces an overall wheel slip consideration for the ALV, which greatly improves the accuracy of the velocity estimation, especially when the inertial sensor is low cost. Additionally, the proposed integrated system uses double-difference pseudorange measurements instead of single point positioning results provided by low-cost GNSS receivers, which greatly improves the accuracy of the position estimation. To verify the navigation performance of the proposed integrated system, comparisons between the states estimated by the proposed system, the EKF-based integrated system and the joint wheel-slip and motion-estimation system are provided. The results of the experiment show that the proposed integrated system has the highest accuracy in both the position estimation and the velocity estimation among the three compared systems, and can improve the navigation performance during GNSS signals outages.

A framework of time integration methods for nonsmooth systems with unilateral constraints

A framework of time integration methods for nonsmooth systems with unilateral constraints is established in this paper, which solves non-impulsive dynamic equations at every step, and deals with impulsive dynamic equations at the end of steps that may involve impacts. The computational procedures of the Generalized-α method and the Bathe method are provided to show this framework, and how to select auxiliary parameters in the procedure is discussed for the benefit of applications. In addition, to avoid high penetration depth and improve the accuracy of detection, an adjustable step size strategy is developed. The provided procedures possess second-order accuracy for smooth motion, and errors caused by the approximate treatment of impacts are controlled by setting an allowable penetration depth. Besides, the observed oscillations of contact forces at contact boundary can be effectively filtered out by the Bathe method. Compared with the classical Moreau-Jean time-stepping scheme, the numerical experiment of the slider-crank mechanism validates that the proposed framework enjoys advantages on accuracy and efficiency.

Research on Configuration Methods of Battery Energy Storage System for Pure Electric Bus Fast Charging Station

With the pervasiveness of electric vehicles and an increased demand for fast charging, stationary high-power fast-charging is becoming more widespread, especially for the purpose of serving pure electric buses (PEBs) with large-capacity onboard batteries. This has resulted in a huge distribution capacity demand. However, the distribution capacity is limited, and in some urban areas the cost of expanding the electric network capacity is very high. In this paper, three battery energy storage system (BESS) integration methods—the AC bus, each charging pile, or DC bus—are considered for the suppression of the distribution capacity demand according to the proposed charging topologies of a PEB fast-charging station. On the basis of linear programming theory, an evaluation model was established that consider the influencing factors of the configuration: basic electricity fee, electricity cost, cost of the energy storage system, costs of transformer and converter equipment, and electric energy loss. Then, a case simulation is presented using realistic operation data, and an economic comparison of the three configurations is provided. An analysis of the impacts of each influence factor in the case study is discussed to verify the case results. The numerical results indicate that the appropriate BESS configuration can significantly reduce the distribution demand and stationary cost synchronously.

Extended MANA Formulation for Time-domain Simulations of Combined Power and Gas Networks

Abstract The promise of improved system efficiency, reliability, and higher renewable energy hosting capability of the Integrated Energy System concept has driven the development of innovative network coupling technologies and energy system integration methods. Co-ordinated design and operation of the traditionally separate energy systems, including electric power, gas, and heat will lead to the optimal use of synergies between energy networks and bring forth numerous benefits to the energy sector. To fully understand the potential and quantitatively assess the operation performance of the combined energy networks, a unified modeling and simulation framework using an extended MANA formulation is proposed in this paper, which is capable of incorporating arbitrary gas network configurations and unbalanced power networks in a systematic manner needed. A case study with combined power and gas networks via EnergyHubs is implemented to demonstrate the application of the proposed method.

Variational Integrators for Parameter Identification of Mechanical Systems

AbstractNumerical methods for parameter identification of dynamical systems are based on matching model outputs to measurements. Computing the model output requires numerical integration techniques, though. In this contribution, we study the role of integration methods for mechanical systems. Since mechanical systems have characteristic properties, using structure‐preserving integration methods suggests itself. First and second order methods are compared in the case study of a damped pendulum.

Method for Measuring Clearance of Automobile Body Panel with Double Structured Light System

According to the changes of the autobody measuring clearance often face the shooting angle problem caused by internal decline caused by the lack of data acquisition accuracy, a high precision and robust measurement of binocular gap line structured light and the system parameter calibration method of system integration. First the mathematical measurement model of the system is established according to the Zhang Zhengyou camera calibration model to calculate the camera parameters, the extrinsic parameters of the camera calibration of the light plane, while the introduction of auxiliary line structured light laser by solving the intersection of two camera coordinate system, finally gives the calculation model of the door gap and combined with the calibration data for the gap size. Compared with a three-dimensional scanning measuring device, the system can measure only two images at the same time. The experimental results show that when the shooting angle is less than 45 degrees at the working distance of 400mm and 50*50 field of view, the accuracy reaches 0.08mm, which meets the needs of fast and real-time measurement gap.

Micromachining integration platform for sub-terahertz and terahertz systems

AbstractWe demonstrate a sub-terahertz (THz) and THz integration platform based on micromachined waveguides on silicon. The demonstrated components in the frequency range 225–325 GHz include waveguides, filters, waveguide vias, and low-loss transitions between the waveguide and the monolithic integrated circuits. The developed process relies on microelectromechanical systems manufacturing methods and silicon wafer substrates, promising a scalable and cost-efficient system integration method for future sub-THz and THz communication and sensing applications. Low-temperature Au/In thermo-compression and Au–Au laser bonding processes are parts of the integration platform enabling integration of millimeter-wave monolithic integrated circuits.

Composite symmetric general linear methods (COSY-GLMs) for the long-time integration of reversible Hamiltonian systems

In choosing a numerical method for the long-time integration of reversible Hamiltonian systems one must take into consideration several key factors: order of the method, ability to preserve invariants of the system, and efficiency of the computation. In this paper, 6th-order composite symmetric general linear methods (COSY-GLMs) are constructed using a generalisation of the composition theory associated with Runge–Kutta methods (RKMs). A novel aspect of this approach involves a nonlinear transformation which is used to convert the GLM to a canonical form in which its starting and finishing methods are trivial. Numerical experiments include efficiency comparisons to symmetric diagonally-implicit RKMs, where it is shown that COSY-GLMs of the same order typically require half the number of function evaluations, as well as long-time computations of both separable and non-separable Hamiltonian systems which demonstrate the preservation properties of the new methods.

Overview of MEA key technology and system integration

More electric aircraft (MEA) becomes a trend for next generation aircraft to respond to the global wide energy shortage. The technological advancement in power electronics makes MEA possible. Airbus and Boeing have advanced their research and application 30 years or earlier than China does. As a major civil aircraft manufacturer in China, COMAC can play an important role in applying and promoting new technologies for next generation aircraft. Based on authors' practice in recent years MEA development project, in this study, the challenge for MEA design is identified and the key technologies for MEA are elaborated from the aircraft, system and component level, and an attempt is made to address the challenge encountered. The method for MEA system integration is given in lieu of ARP 4754A. Finally, an innovative collaboration between original equipment manufacturer (OEM) and suppliers is suggested to achieve win–win situation in developing next generation aircraft.

Packaging without the Package - A More Holistic Moore's Law

Silicon features have scaled by over 1500X for over six decades, and with the adoption of innovative materials delivered better power-performance, density and till recently, cost per function, almost every generation. This has spawned a vibrant system-on-chip (SoC) approach, where progressively more function has been integrated on a single die. The integration of multiple dies on packages and boards has, however, scaled only modestly by a factor of three to five times. However, as SoCs have become bigger and more complex, the Non-Recurring Engineering (NRE) Charge and time to market have both ballooned out of control leading to ever increasing market consolidation. We need to address this problem through novel methods of system Integration. With the well-documented slowing down of scaling and the advent of the Internet of Things, there is a focus on heterogeneous integration and system-level scaling. Packaging itself is undergoing a transformation that focuses on overall system performance through integration rather than on packaging individual components. We propose ways in which this transformation can evolve to provide a significant value at the system level while providing a significantly lower barrier to entry compared with a chip-based SoC approach that is currently used. More importantly it will allow us to re-architect systems in a very significant way. This transformation is already under way with 3-D stacking of dies, Wafer level fan-out processing, and will evolve to make heterogeneous integration the backbone of a new SoC methodology, extending to integrate entire Systems on Wafers (SoWs). We will describe the technology we use and the results to-date. This has implications in redefining the memory hierarchy in conventional systems and in neuromorphic systems. We extend these concepts to flexible and biocompatible electronics.

Integration methods for thermosensitive gel systems in garments

Humans live and work under severe thermophysiological conditions, which are characterized by extreme temperatures and humidities. Furthermore, additional burdens can arise from physical activities of the human body or the work conditions (resulting in psychological stress) [1]. The thermoregulation of the human body compensates such situations and maintains the core body temperature at 37°C (98,6 °F). The currently used systems for supporting human thermoregulation, such as PCM-equipped surface structures or mobile water-based cooling units have the disadvantage that the running cooling process is neither switchable nor reversible. Another promising possibility for a personal cooling is the use of temperature-dependent superabsorbers (so-called LCST and UCST) in garments, which absorb the human sweat and transmit it to the environment by evaporation. Cooling during evaporation results in heat transfer from the human body.

A Safety Management and Signaling System Integration Method for Communication-Based Train Control System

The safety and the correctness of signaling system not only relate to the safety and efficiency of the rail transit operation, but also link with the life safety of passengers. In order to guarantee the safety of a signaling system for metro, the safety certificate for the trial operation with carrying passengers must be obtained. In this paper, a suitable safety management and signaling system integration model are explored according to the CENELEC standards and applied in China. With taking account of the strict safety requirements for the Communication-Based Train Control (CBTC) system, a safety assurance and assessment method based on safety verification and validation process was put forward. This method was applied in every phase of the CBTC system development life cycle to monitor and control each activity in the life cycle and to review each document in system development process. At the same time, this method is also used to ensure the traceability of relevant documents and to test all the functions of the whole system sufficiently and completely. So that the safety operation of train control system can be ensured. Up to now, the independently developed CBTC system with the safety management had been applied in many urban rail transit lines of Beijing, such as Yizhuang Line, Changping Line, Line No. 14, and Line No. 7. The CBTC signaling systems of these projects have been authorized by the safety certification from a third party, e.g., Lloyd Register which is a British company and famous for the safety verification and validation process.

복합유도방식이 적용된 유도탄의 탑재비행시험(CFT) 시스템 구성 및 검증

A Captive Flight Test(CFT) is used to verify the performance of missile component such as seeker and guiding algorithm of missile. Recently most of surface to air missile adapts multi-mode guidance method which include command guidance and active/passive guidance. A CFT system for missile system adapting multi-mode guidance method consists of pod equipment, command transmitting system and measuring system. In this paper, we proposed CFT system and testing method for missile which adapt multi-mode guidance, and system integration procedure by using distributed missile system integration method and procedure. The proposed CFT system and system integration method was applied to CFT of surface to air missile, and brought successful result.

2.3 µm range InP-based type-II quantum well Fabry-Perot lasers heterogeneously integrated on a silicon photonic integrated circuit.

Heterogeneously integrated InP-based type-II quantum well Fabry-Perot lasers on a silicon waveguide circuit emitting in the 2.3 µm wavelength range are demonstrated. The devices consist of a "W"-shaped InGaAs/GaAsSb multi-quantum-well gain section, III-V/silicon spot size converters and two silicon Bragg grating reflectors to form the laser cavity. In continuous-wave (CW) operation, we obtain a threshold current density of 2.7 kA/cm2 and output power of 1.3 mW at 5 °C for 2.35 μm lasers. The lasers emit over 3.7 mW of peak power with a threshold current density of 1.6 kA/cm2 in pulsed regime at room temperature. This demonstration of heterogeneously integrated lasers indicates that the material system and heterogeneous integration method are promising to realize fully integrated III-V/silicon photonics spectroscopic sensors in the 2 µm wavelength range.

Combining solar resource mapping and energy system integration methods for realistic valuation of urban solar energy potential

To increase the use of solar energy in cities, this paper proposes an integrated model for urban solar mapping combining solar resource potential assessment and energy system integration models. Bringing urban solar energy to a system level gives a more realistic estimate of the useable solar potential in cities. The model is intended for a first estimate of the potential and it needs a limited amount of input data, typical in developing countries. The first sub-model comprises a step-by-step approach starting with a global temporal solar radiation pattern to which spatial urban and building topologies are linked to assess solar losses. Next the available solar energy potential is estimated according to type of housing, solar energy technology, and demand patterns. The second sub-model on energy systems uses the output from the solar resource model by putting the building specific solar energy data into the energy system level, considering the energy infrastructure such as the electric grid and finally yielding an estimate of the useable solar potential in a city. We apply the model to the city of Concepción in Chile as a test case to show the versatility of it.

Classification of solutions to Toda systems of types C and B with singular sources

In this paper, the classification in Lin et al. (Invent. Math. 190(1):169–207, 2012) of solutions to Toda systems of type A with singular sources is generalized to Toda systems of types C and B. Like in the A case, the solution space is shown to be parametrized by the abelian subgroup and a subgroup of the nilpotent subgroup in the Iwasawa decomposition of the corresponding complex simple Lie group. The method is by studying the Toda systems of types C and B as reductions of Toda systems of type A with symmetries. The theories of Toda systems as integrable systems as developed in Leznov (Teoret. Mat. Fiz. 42(3):343–349, 1980), Leznov and Saveliev (Group-theoretical methods for integration of nonlinear dynamical systems, Progress in Physics, vol. 15. Birkhauser, Verlag, 1992), Nie (J. Geom. Phys. 62(12):2424–2442, 2012), Nie (J. Nonlinear Math. Phys. 21(1):120–131, 2014), in particular the W-symmetries and the iterated integral solutions, play essential roles in this work, together with certain characterizing properties of minors of symplectic and orthogonal matrices.

Expertise, credibility of system forecasts and integration methods in judgmental demand forecasting

Expert knowledge elicitation lies at the core of judgmental forecasting—a domain that relies fully on the power of such knowledge and its integration into forecasting. Using experts in a demand forecasting framework, this work aims to compare the accuracy improvements and forecasting performances of three judgmental integration methods. To do this, a field study was conducted with 31 experts from four companies. The methods compared were the judgmental adjustment, the 50–50 combination, and the divide-and-conquer. Forecaster expertise, the credibility of system forecasts and the need to rectify system forecasts were also assessed, and mechanisms for performing this assessment were considered. When (a) a forecaster’s relative expertise was high, (b) the relative credibility of the system forecasts was low, and (c) the system forecasts had a strong need of correction, judgmental adjustment improved the accuracy relative to both the other integration methods and the system forecasts. Experts with higher levels of expertise showed higher adjustment frequencies. Our results suggest that judgmental adjustment promises to be valuable in the long term if adequate conditions of forecaster expertise and the credibility of system forecasts are met.

The efficiency of second derivative multistep methods for the numerical integration of stiff systems

A substantial increase in efficiency is achieved by the numerical integration methods which take advantage of the second derivative terms of the differential equation to be solved. The second-derivative of high order accuracy methods are stable, convergent and hence suitable for the numerical integration of stiff systems of initial value problems in ordinary differential equations. The unique feature of the paper is the idea of using all the set of collocation points as additional interpolation points. This desirable feature of the proposed approach actually widens the applicability of the methods, to include many other types of numerical integration methods and has many advantages, including didactic advantages. Furthermore, in this formulation symmetry is retained naturally by the integration identities as equal areas under the various segments of the solution curves over the integration interval. In this way the problem of overlap of solution models usually associated with multistep finite difference methods is overcome. The applications of the second derivative multistep integration methods on a significant class of problems found in the literature produce accurate solutions with low computational cost. Comparison of the efficiency curves obtained seems to be in better agreement with the exact solutions.