General System Configuration Research Articles

Characterizing three-dimensional general arrangements and distributed system configurations utilizing an architecturally normalized current representation

Designing ships involves intricate layouts and multifaceted systems—ranging from mechanical to operational—that must be interdependent and thus precisely arranged. Traditional automated tools, though effective, are often too resource-intensive to be feasibly employed during the critical early stages of design. This paper builds on prior work that introduced an innovative solution: a network-based, architecturally normalized current representation, which offers a computational method to predict system arrangements in two dimensions without generating detailed vessel models. Our method’s advantage lies in its ability to guide early stage design decisions, thereby optimizing the use of subsequent, more resource-intensive design tools. This study extends the method to a three-dimensional framework, capturing more nuanced system-to-system interactions and yielding more realistic ship arrangements. A methodology was proposed to support this three-dimensional extension and demonstrate its applicability through a case study focused on the conceptual design of a naval frigate.

Studies Regarding the Modeling of a Wind Turbine with Energy Storage

This paper presents the modeling in Matlab-Simulink of a stand-alone wind turbine system with energy storage dedicated for small power wind turbines of 3kW with a variable speed permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge controller, transformer, inverter, ac loads and energy storage devices. Are presented the general system configuration, the Simulink block diagram and the main simulated characteristics resulting from the dynamic performances during the wind speed variation.

Artificial Noise-Aided Secure Relay Communication With Unknown Channel Knowledge of Eavesdropper

In this article, a new relay-aided secure communication system is investigated, where a transmitter sends signals to a destination via an amplify-and-forward (AF) relay in the presence of an eavesdropper. We consider a general system configuration, where the source, relay, destination, and eavesdropper are all equipped with multiple antennas. In the practical scenarios of unknown eavesdropper's channel state information (CSI) and uncertainty of the eavesdropper's location, we aim to maximize the expected value of the system secrecy rate over the presumed distribution of the eavesdropper's channels, by exploiting the artificial noise (AN) transmitted by the source and relay nodes. The system design issue is formulated as a nonconvex stochastic optimization problem with a source transmission power constraint and a nonconvex relay transmission power constraint. A novel computational method is proposed to solve this challenging problem. The new method is developed based on an exact penalty function method together with a parallel stochastic decomposition algorithm. Numerical simulations are performed to study the effectiveness of the proposed scheme at various locations of the eavesdropper. Simulation results show that for most cases, secure communication can be achieved without the CSI knowledge of eavesdropper's channels, and the achievable secrecy rate follows the trend of a benchmark system where the eavesdropper's full CSI is available. In particular, the achievable system secrecy rate increases with the number of antennas at the legitimate users. Moreover, the optimal power allocated for the transmission of the AN increases with the system signal-to-noise ratio. The proposed computational method achieves a higher system secrecy rate than a conventional penalty function based approach.

Seismic Fragility Assessment of Base-Isolated Steel Water Storage Tank

Steel water storage tanks (WSTs) are among the important components of water treatment industry facilities that are expected to remain functional and applicable after strong earthquakes. In this study, the seismic vulnerability of base-isolated steel WST is investigated. A three-dimensional finite element stick model of the targeted tank is created using OpenSees. This model is capable of reproducing convective, impulsive, and rigid responses of fluid-tank systems. Time-history responses of convective displacement, bearing displacement, and base shear force for base-isolated tank subjected to a typical ground motion are compared. Furthermore, time-history analysis based on a suite of 80 ground motions is conducted. The seismic demand models for various responses are established and the most efficient intensity measure (IM) is determined based on the dispersion and coefficient of determination. Seismic fragility curves for different responses are derived for all three damage states using cloud analysis. The results from this study reveal that (i) the convective displacement is significantly greater than bearing displacement; (ii) peak ground displacement (PGD) is the most efficient and sufficient IM for the targeted tank; and (iii) the characteristic of isolation bearing significantly influences the seismic fragilities of convective displacement and bearing displacement and has a little impact on base shear force, which makes the selection of the proper characteristic parameters for isolation bearing very essential. The analysis technique and procedure mentioned above as well as derived insights are of significance to general liquid storage tank system configuration.

The impact of conditional dependence on checked baggage screening

Checked baggage screening, an important layer of an aviation security system, has gained a lot of research interest in the literature. Due to the different characteristics (for example, cost, capacity, and efficiency) of various screening devices, several cost-benefit models have been proposed to help select screening devices to include in a checked baggage screening system. Almost all cost-benefit models involving multiple devices implicitly assume that, given that a bag carries a threat or not, the responses from different screening devices are conditionally independent. This assumption may not hold in real situations because one device’s response may be positively or negatively correlated with another device’s response. In this paper, we bridge this research gap and address the impact of conditional dependence on checked baggage screening based on a more general system configuration and an existing cost-benefit model. The cost-benefit model investigates a two-device screening system with the objective of minimizing the expected cost per bag. Our detailed numerical results suggest that (1) the higher the correlation coefficient, the higher the optimal expected cost per bag, (2) incorporating correlation coefficients may even alter the choice of devices to include in the optimal screening system, and (3) the more the responses are correlated, the higher the relative increase of the optimal expected cost per bag when ignoring conditional dependence.

Characterizing general arrangements and distributed system configurations in early-stage ship design

General arrangement and distributed system design is a complex problem that is a fundamental aspect of ship design. Current approaches to this design problem employ a paradigm of using automated tools to generate and analyze potential vessel solutions. These approaches rely on the generation and optimization of vessel models based on design parameters. Created vessel models are then evaluated and compared to understand how parameters influence possible vessel characteristics. This process is time and resource intensive, which limits its application in early-stage design when many critical arrangement and distributed system design decisions are made. In this paper a new approach is proposed to complement the automated tool-based paradigm. For a vessel with a defined set of systems to be arranged and connected, the approach measures the probabilistic arrangement and distributed system configuration, without generating vessel models. This efficiently provides leading indicators of the expected design outcomes and resultant vessel characteristics, which can help guide early-stage decisions and lead to better applications of resource-intensive design tools. In this paper, methods supporting this approach are presented and application is demonstrated on a naval frigate concept design.

Anyonic entanglement and topological entanglement entropy

We study the properties of entanglement in two-dimensional topologically ordered phases of matter. Such phases support anyons, quasiparticles with exotic exchange statistics. The emergent nonlocal state spaces of anyonic systems admit a particular form of entanglement that does not exist in conventional quantum mechanical systems. We study this entanglement by adapting standard notions of entropy to anyonic systems. We use the algebraic theory of anyon models (modular tensor categories) to illustrate the nonlocal entanglement structure of anyonic systems. Using this formalism, we present a general method of deriving the universal topological contributions to the entanglement entropy for general system configurations of a topological phase, including surfaces of arbitrary genus, punctures, and quasiparticle content. We analyze a number of examples in detail. Our results recover and extend prior results for anyonic entanglement and the topological entanglement entropy.

Seismic Performance of a Soil-Pile-Bridge: Three-Dimensional Finite Element Simulation

Soil-Structure Interaction (SSI) is involved in the seismic performance of pile-supported bridge. Such effect includes soil-pile interaction driven by the deformation of pile and surrounding soil. This interaction might be further pronounced due to large soil deformation during earthquake. To capture this characteristic, a three-dimensional (3D) finite element (FE) simulation is conducted considering soil-pile interaction along with the corresponding numerical details. The prototype system of a two-span reinforced concrete bridge with a single pier is demonstrated in multi-layered clay. The overall seismic response of the coupled soil-pile-bridge system are systematically investigated. The simulated results showed that the inertial effect of superstructure and transversal configuration of bridge significantly influence the pile response. The analysis technique as well as the derived insights are of significance to general pile-supported bridge system configurations.

Comprehensive Study of Equalization-Enhanced Phase Noise in Coherent Optical Systems

A thorough analysis of equalization-enhanced phase noise (EEPN) and its impact on the coherent optical system is presented. We show with a time-domain analysis that EEPN is caused due to the interference of multiple delayed versions of the dispersed signal, generated by intermixing of the received dispersed signal, and the noise side bands of the local oscillator (LO) in the photodetectors. We derive statistical properties such as the mean, variance, and error vector magnitude of the received signal influenced with EEPN. We show that in coherent optical systems utilizing electronic dispersion compensation, this noise corresponds to multipath fading in wireless communication systems. Closed-form expressions of necessary LO linewidth and/or mitigation bandwidth for a general system configuration and specified OSNR penalty are given. The expressions for system design parameters, validated with system simulations, show that higher order modulation formats, such as 16-quadrature amplitude modulation and beyond, put stringent demands on the LO linewidth unless a mitigation technique is used.

Mixed Autonomous/Teleoperation Control of Asymmetric Robotic Systems

This paper presents a unified framework for system design and control in human-in-the-loop asymmetric robotic systems. It introduces a highly general teleoperation system configuration involving any number of operators, haptic interfaces, and robots with possibly different degrees of mobility. The proposed framework allows for mixed teleoperation/autonomous control of user-defined subtasks by establishing position/force tracking as well as kinematic constraints among relevant teleoperation control frames. The control strategy is hierarchical comprising of a high-level teleoperation coordinating controller and low-level joint velocity controllers. The approach utilizes idempotent, generalized pseudoinverse and weighting matrices in order to achieve new performance objectives that are defined for such asymmetric semi-autonomous teleoperation systems. Three layers of velocity-based autonomous control at different priority levels with respect to human teleoperation are integrated into the framework. A detailed analysis of system performance and stability is presented. Experimental results with a single-master/dual-slave system configuration demonstrate an application of the proposed system design and control strategy.

Feedback Bit Allocation Schemes for Multi-User Distributed Antenna Systems

In this paper, we propose a feedback bit allocation algorithm for multi-user downlink distributed antenna systems with limited feedback. We consider a composite fading channel with small scale fadings and path loss, and assume the case where each user is served by only one distributed antenna (DA) port while each DA port can support any number of users. In order to efficiently determine bit allocation, we propose an iterative algorithm which minimizes an upper bound of a mean rate loss. Compared to conventional bit allocation methods, the proposed algorithm can be applied to more general system configurations. Simulation results show that our proposed algorithm offers a performance gain of 20% over an equal bit allocation scheme.

Design of Mobility System for Ground Model of Planetary Exploration Rover

In recent years, a number of missions have been planned and conducted worldwide on the planets such as Mars, which involves the unmanned robotic exploration with the use of rover. The rover is an important system for unmanned planetary exploration, performing the locomotion and sample collection and analysis at the exploration target of the planetary surface designated by the operator. This study investigates the development of mobility system for the rover ground model necessary to the planetary surface exploration for the benefit of future planetary exploration mission in Korea. First, the requirements for the rover mobility system are summarized and a new mechanism is proposed for a stable performance on rough terrain which consists of the passive suspension system with 8 wheeled double 4-bar linkage (DFBL), followed by the performance evaluation for the mechanism of the mobility system based on the shape design and simulation. The proposed mobility system DFBL was compared with the Rocker-Bogie suspension system of US space agency National Aeronautics and Space Administration and 8 wheeled mobility system CRAB8 developed in Switzerland, using the simulation to demonstrate the superiority with respect to the stability of locomotion. On the basis of the simulation results, a general system configuration was proposed and designed for the rover manufacture.

Estimation of reliability characteristics of general system configuration

PurposeThe purpose of this paper is to consider a General System Configuration (GSC), whose particular cases are all the popular system configurations. In reliability engineering one comes across various system configurations, for example, series, parallel and k‐out of‐m system models, which consist of a number of components.Design/methodology/approachThe paper gives a general approach to express the reliability properties of the whole system in terms of component parameters. The reliability of a GSC is expressed as a polynomial of the component reliability. Lifetime data on components have been used to estimate the system reliability characteristics through classical and Bayes estimation procedures.FindingsThe paper finds that the underlying distribution is assumed to be Weibull and, in view of cost constraints, Type‐II censored information has been used.Practical implicationsThe paper is useful for reliability practitioners as well as theoreticians. It provides an easy method to estimate the reliability of any system configuration.Originality/valueThree types of estimation procedures for a general system configuration have been developed for the first time. The lifetimes of components are assumed to follow widely used Weibull distribution, whose particular case is the most popular exponential distribution.

ＧＰＳブイアレーによる波浪情報観測システム

In this paper, the wave observation system by arrayed buoys whose three dimensional movements are measured precisely by the kinematic GPS is proposed. Firstly, the general concept and system configuration of this observation system are described. The proposed wave observation system measures the three-dimensional movements of each observational buoy relative to the fixed reference station by the kinematic GPS. Because the distance between the reference station and each buoy is about several kilometers at most, the measurement error of the kinematic GPS can be estimated less than a few centimeters. The data of each observational buoy are sent to the reference station by radio telemetry system, and then the data are used to estimate effective information about wave such as period, wavelength, height and direction. Finally, it is shown that this proposed system is able to estimate the propagation directions of waves of the same period propagated from various directions by high resolution and analyzing ability.

A model for combustion instability involving vortex shedding

Vigorous burning of vortices, formed behind flame stabilizers, can drive significant pressure oscillations inside premixed-type combustors. The goal of this work is to derive a reduced-order model for interaction among vortex shedding, chamber acoustics, and combustion process. A dump combustor is considered a general system configuration. Formation of vortices at the sudden expansion in a chamber is affected by the oscillatory flow. A new quasi-steady model is proposed for determining the moment of vortex separation. Vortex burning is assumed to be localized in space and time. A "kicked" oscillator model is utilized for deriving the appropriate dynamical system. The moment of burning and the corresponding vortex location are dependent on the chamber geometry, velocity field, and characteristic chemical and hydrodynamic times. If Rayleigh's criterion is satisfied, acoustic waves can develop in the chamber. Model and experimental results are compared for a chosen configuration. A study of model performance for a realistic system is carried out by variation of parameters where the mean flow velocity and the number of modes are treated as variables.

A hybrid push/pull control algorithm for multi-stage, multi-line production systems

In this research, a hybrid push/pull production control algorithm is developed and tested for use in a multi-stage, multi-line, assembly-type repetitive manufacturing environment. The algorithm is primarily based on a just-in-time (JIT) approach, but uses dependent demand aspects of manufacturing resources planning (MRP II) to manage the intermediate inventories. A simulation model is then developed to test the algorithm on general system configurations, on the bases of output, lead time and WIP. The simulation results show the algorithm to be effective in minimizing WIP while sustaining output capacity, with relatively little sacrifice in total lead times from the best observed values.

Analytical Expressions of the Stability and Bifurcation Boundaries for General Spread Mooring Systems

Spread mooring systems (SMS) are labeled as general when they are not restricted by conditions of symmetry. The six necessary and sufficient conditions for stability of general SMS are derived analytically. The boundaries where static and dynamic loss of stability occur also are derived in terms of the system eigenvalues, thus providing analytical means for defining the morphogenesis that occurs when a bifurcation boundary is crossed. The equations derived in this paper provide analytical expressions of elementary singularities and routes to chaos for general mooring system configurations. Catastrophe sets are generated first by the derived expressions and then numerically using nonlinear dynamics and codimension-one and -two bifurcation theory; agreement is excellent. The mathematical model consists of the nonlinear, third-order maneuvering equations without memory of the horizontal plane, slow-motion dynamics—surge, sway, and yaw—of a vessel moored to several terminals. Mooring lines can be modeled by synthetic nylon ropes, chains, or steel cables. External excitation consists of time-independent current, wind, and mean wave drift forces. The analytical expressions derived in this paper apply to nylon ropes and current excitation. Expressions for other combinations of lines and excitation can be derived.

A generalized design and performance analysis model for end-of-aisle order-picking systems

In this paper we present an analytical design algorithm to determine the near-minimum number of pickers required in an end-of-aisle order-picking operation based on a miniload automated storage/retrieval system. The algorithm is based on an approximate analytical model we developed to estimate the expected picker utilization (and the storage/retrieval machine utilization) for general system configurations with two or more pick positions per aisle and/or two or more aisles per picker. For systems with two pick positions, we also investigate the possibility of improving the picker utilization by sequencing container retrievals within each order.

Error analysis of 3D shape construction from structured lighting

In this paper, we present a detailed model and analysis of several error sources and thier effects on measuring three-dimensional (3D) surface properties using the structured lighting technique. The analysis is based on a general system configuration and identifies three types of error surces—system modeling error, image processing error and experimental error. Absolute and relative error bounds in obtaining 3D surface orientation and curvature measurements using structured lighting are derived in terms of the system parameters and likely error sources. In addition to the quantization error, other likely error sources in system modeling and experimental setup are also considered. Even though our analysis is on structured lighting, the results are readily applicable to other triangulation-based techniques such as stereopsis. Finally, our analysis focuses on error in inferring surface orientation and principal surface curvature. Such analyses, to our knowledge, have never been attempted before.

Sensory guidance of seam tracking robots

The primary goal of a seam tracking robot, based on sensory feedback, is to maintain a prescribed relationship between the end effector and the workpiece throughout the whole motion of the manipulator along the nominal path. The purpose of this article is to present the essential conceptual and theoretical features of a high-speed seam tracking controller for sealant application. The general system configuration is discussed, followed by a brief account of the key aspects involved with the sensing of the seam location and subsequent correction command generation for the guidance of the robot. The theoretical considerations are followed by a detailed account of the physical implementation of the proposed system, with performance evaluation data obtained under actual working conditions. © 1994 John Wiley & Sons, Inc.