文化符号视角下的澳门旅游纪念品设计研究

目的 以文化符号的象征性含义为切入点,探索澳门旅游纪念品设计的有效方法,促进澳门文化传播和旅游纪念品产业发展。方法 首先,对澳门旅游产业发展进行必要介绍,并梳理分析国内外学者对旅游纪念品属性与开发设计方面的研究成果,得出从文化符号角度进行澳门旅游纪念品设计研究的必要性;其次,通过对符号概念的阐述,定义文化符号的主题类别,继而在文化符号借用象征方式和隐喻象征方式中构建旅游纪念品的设计架构;最后,调查和分类澳门文化符号的内容,给出澳门旅游纪念品的设计方法,同时通过设计实例加以说明。结论 文化符号的借用与隐喻设计方法能有效帮助设计师从象征角度完成旅游纪念品的设计,关键是找到文化符号与旅游纪念品之间的象征性联系。这对设计理论研究和旅游纪念品设计创新具有重要价值。     

Symmetric Level Index Arithmetic in Simulation and Modeling

This paper begins with a general introduction to the symmetric level-index, SLI, system of number representation and arithmetic. This system provides a robust framework in which experimental computation can be performed without the risk of failure due to overflow/underflow or to poor scaling of the original problem. There follows a brief summary of some existing computational experience with this system to illustrate its strengths in numerical, graphical and parallel computational settings. An example of the use of SLI arithmetic to overcome graphics failure in the modeling of a turbulent combustion problem is presented. The main thrust of this paper is to introduce the idea of SLI-linear least squares data fitting. The use of generalized logarithm and exponential functions is seen to offer significant improvement over the more conventional linear regression tools for fitting data from a compound exponential decay such as the decay of radioactive materials.     

Three‐dimensional time‐harmonic Green's functions for a triclinic full‐space using a symbolic computation system

Time‐harmonic Green's functions for a triclinic anisotropic full‐space are evaluated through the use of a symbolic computation system.This procedure allows evaluation of the Green's functions for the most general anisotropic materials. The proposed computational algorithms are programmed in a MATLAB environment by incorporating symbolic calculations performed using Maple Computer Algebra System. Extensive testing of the numerical results has been performed for both displacement and stress fields. The tests demonstrate the accuracy of the proposed algorithm in evaluating the Green's functions. Copyright © 2001 John Wiley & Sons, Ltd.     

Algorithms for optoelectronic implementation of modified signed-digit division, square-root, logarithmic, and exponential functions

Algorithms for computing complex elementary functions based on the modified signed-digit (MSD) number system representations are proposed. An arithmetic unit that performs parallel one-step addition (subtraction), multiplication, and division is proposed to achieve the computation of complex functions such as the square-root, logarithm, exponential, and other related operations. An optoelectronic correlator-based architecture is suggested for implementing the proposed MSD algorithms to compute the above-mentioned elementary functions. We utilized the symbolic substitution technique to reduce the number of computation rules involved.     

Value function approximation via linear programming for FMS scheduling

In this paper, we develop a linear programming framework for computing a quadratic approximation to the value function, which constitutes the off-line computation of a hierarchical FMS scheduling approach previously developed by us. In contrast to previous work, where relatively crude value functions were used, we develop a quadratic approximation that is a prior fit. We consider the multiple part multiple machine discounted cost case and illustrate the approach via a simulation example in the context of an industrial setting.     

Parallel computing of high‐speed compressible flows using a node‐based finite‐element method

An efficient parallel computing method for high‐speed compressible flows is presented. The numerical analysis of flows with shocks requires very fine computational grids and grid generation requires a great deal of time. In the proposed method, all computational procedures, from the mesh generation to the solution of a system of equations, can be performed seamlessly in parallel in terms of nodes. Local finite‐element mesh is generated robustly around each node, even for severe boundary shapes such as cracks. The algorithm and the data structure of finite‐element calculation are based on nodes, and parallel computing is realized by dividing a system of equations by the row of the global coefficient matrix. The inter‐processor communication is minimized by renumbering the nodal identification number using ParMETIS. The numerical scheme for high‐speed compressible flows is based on the two‐step Taylor–Galerkin method. The proposed method is implemented on distributed memory systems, such as an Alpha PC cluster, and a parallel supercomputer, Hitachi SR8000. The performance of the method is illustrated by the computation of supersonic flows over a forward facing step. The numerical examples show that crisp shocks are effectively computed on multiprocessors at high efficiency. Copyright © 2003 John Wiley & Sons, Ltd.     

Computation of periodic Green's functions of Stokes flow

Methods of computing periodic Green's functions of Stokes flow representing the flow due to triply-, doubly-, and singly-periodic arrays of three-dimensional or two-dimensional point forces are reviewed, developed, and discussed with emphasis on efficient numerical computation. The standard representation in terms of Fourier series requires a prohibitive computational effort for use with singularity and boundary-integral-equation methods; alternative representations based on variations of Ewald's summation method involving various types of splitting between physical and Fourier space with partial sums that decay in a Gaussian or exponential manner, allow for efficient numerical computation. The physical changes undergone by the flow in deriving singly- and doubly-periodic Green's functions from their triply-periodic counterparts are considered.     

Computing Switching Surfaces in Optimal Control Based on Triangular Decomposition

Various algorithms for optimal control require the explicit determination of switching surfaces. However, switching strategies may be very complicated, such that the computation of switching surfaces is quite challenging. General methods are proposed here to compute switching surfaces systematically, based on algebraic computational tools such as triangular decomposition. Our methods are highly complex compared to some widely-used numerical options, but they can be made feasible for real-time applications by moving the computational burden off-line. The tutorial-style presentation is intended to introduce potentially powerful symbolic computation methods to system scientists in particular, and an illustrative example of time-optimal control is given to show the effectiveness and generality of our approach.     

Efficient Computation Offloading in Mobile Cloud Computing for Video Streaming Over 5G

In this paper, we investigate video quality enhancement using computation offloading to the mobile cloud computing (MCC) environment. Our objective is to reduce the computational complexity required to covert a low-resolution video to high-resolution video while minimizing computation at the mobile client and additional communication costs. To do so, we propose an energy-efficient computation offloading framework for video streaming services in a MCC over the fifth generation (5G) cellular networks. In the proposed framework, the mobile client offloads the computational burden for the video enhancement to the cloud, which renders the side information needed to enhance video without requiring much computation by the client. The cloud detects edges from the upsampled ultra-high-resolution video (UHD) and then compresses and transmits them as side information with the original low-resolution video (e.g., full HD). Finally, the mobile client decodes the received content and integrates the SI and original content, which produces a high-quality video. In our extensive simulation experiments, we observed that the amount of computation needed to construct a UHD video in the client is 50%-60% lower than that required to decode UHD video compressed by legacy video encoding algorithms. Moreover, the bandwidth required to transmit a full HD video and its side information is around 70% lower than that required for a normal UHD video. The subjective quality of the enhanced UHD is similar to that of the original UHD video even though the client pays lower communication costs with reduced computing power.     

Robust chaotic communications exploiting waveform diversity. part 1: Correlation detection and implicit coding

A correlation receiver is presented for communication using the symbolic dynamics of a chaotic system. A chaotic system offers the potential for power efficient transmitters but many proposals to date have either been susceptible to noise and distortion in the channel, or are spectrally inefficient. The proposed system has a spectrum efficiency equivalent to conventional BPSK and offers a 2 dB performance improvement in AWGN. This is achieved by exploiting diversity in the transmitted signal, whereby each data symbol influences the transmitted pulse shape for the preceding symbols. Correlation detection over multiple symbols allows full exploitation of this diversity. In addition, each symbol can be detected multiple times and so a decoding gain is possible without the need for parity symbols. The diversity mechanism is investigated and the performance gains demonstrated.     

Quasi‐Hodgkin–Huxley Neurons with Leaky Integrate‐and‐Fire Functions Physically Realized with Memristive Devices

Artificial neurons with functions such as leaky integrate‐and‐fire (LIF) and spike output are essential for brain‐inspired computation with high efficiency. However, previously implemented artificial neurons, e.g., Hodgkin–Huxley (HH) neurons, integrate‐and‐fire (IF) neurons, and LIF neurons, only achieve partial functionality of a biological neuron. In this work, quasi‐HH neurons with leaky integrate‐and‐fire functions are physically demonstrated with a volatile memristive device, W/WO₃/poly(3,4‐ethylenedioxythiophene): polystyrene sulfonate/Pt. The resistive switching behavior of the device can be attributed to the migration of protons, unlike the migration of oxygen ions normally involved in oxide‐based memristors. With multifunctions similar to their biological counterparts, quasi‐HH neurons are advantageous over the reported HH and LIF neurons, demonstrating their potential for neuromorphic computing applications.     

Brute force meets Bruno force in parameter optimisation: introduction of novel constraints for parameter accuracy improvement by symbolic computation

Recent remarkable advances in computer performance have enabled us to estimate parameter values by the huge power of numerical computation, the so-called 'Brute force', resulting in the high-speed simultaneous estimation of a large number of parameter values. However, these advancements have not been fully utilised to improve the accuracy of parameter estimation. Here the authors review a novel method for parameter estimation using symbolic computation power, 'Bruno force', named after Bruno Buchberger, who found the Gro?bner base. In the method, the objective functions combining the symbolic computation techniques are formulated. First, the authors utilise a symbolic computation technique, differential elimination, which symbolically reduces an equivalent system of differential equations to a system in a given model. Second, since its equivalent system is frequently composed of large equations, the system is further simplified by another symbolic computation. The performance of the authors' method for parameter accuracy improvement is illustrated by two representative models in biology, a simple cascade model and a negative feedback model in comparison with the previous numerical methods. Finally, the limits and extensions of the authors' method are discussed, in terms of the possible power of 'Bruno force' for the development of a new horizon in parameter estimation.     

Modeling complex crack problems using the numerical manifold method

In the numerical manifold method, there are two kinds of covers, namely mathematical cover and physical cover. Mathematical covers are independent of the physical domain of the problem, over which weight functions are defined. Physical covers are the intersection of the mathematical covers and the physical domain, over which cover functions with unknowns to be determined are defined. With these two kinds of covers, the method is quite suitable for modeling discontinuous problems. In this paper, complex crack problems such as multiple branched and intersecting cracks are studied to exhibit the advantageous features of the numerical manifold method. Complex displacement discontinuities across crack surfaces are modeled by different cover functions in a natural and straightforward manner. For the crack tip singularity, the asymptotic near tip field is incorporated to the cover function of the singular physical cover. By virtue of the domain form of the interaction integral, the mixed mode stress intensity factors are evaluated for three typical examples. The excellent results show that the numerical manifold method is prominent in modeling the complex crack problems.     

Symbolic processes in the implementation of technological change: a symbolic interactionist study of work computerization.

This study examined the symbolic processes involved in the computerization of work in a health maintenance organization. Guided by symbolic interaction as a methodological framework, this inductive study used the methods of participant observation and in-depth interviewing for gathering data. It documents the multiple symbols associated with computerization in the organization and discusses local interpretations of those symbolic realities. It also explores the influence of this symbolism on the computerization process.     

Comparing Reliability-Redundancy Tradeoffs for Two von Neumann Multiplexing Architectures

Nanoelectronic systems are anticipated to be highly susceptible to computation and communication noise. Interestingly, von Neumann addressed the issue of computation in the presence of noisy gates in 1952 and developed a technique called multiplexing. He proposed multiplexing architectures based on two universal logic functions, nand and maj. Generalized combinatorial models to analyze such multiplexing architectures were proposed by von Neumann and extended later by others. In this work, we describe an automated method for computing the effects of noise in both the computational and interconnect hardware of multiplexing-based nanosystems-a method employing a probabilistic model checking tool and extending previous modeling efforts, which only considered gate noise. This method is compared with a recently proposed automation methodology based on probabilistic transfer matrices and used to compute and compare the reliability of individual nand and maj multiplexing systems, both in the presence of gate and interconnect noise. Such a comparative study of nand and maj multiplexing is needed to provide quantitative guidelines for choosing one of the multiplexing schemes. The maximum device failure probabilities that can be accommodated by multiplexing-based fault-tolerant nanosystems are also computed by this method and compared with theoretical results from the literature. This paper provides a framework that can capture probabilistically quantified fault models and provide quick reliability evaluation of multiplexing architectures     

Towards error bounds of the failure probability of elastic structures using reduced basis models

Structural reliability methods aim at computing the probability of failure of systems with respect to prescribed limit state functions. A common practice to evaluate these limit state functions is using Monte Carlo simulations. The main drawback of this approach is the computational cost, because it requires computing a large number of deterministic finite element solutions. Surrogate models, which are built from a limited number of runs of the original model, have been developed, as substitute of the original model, to reduce the computational cost. However, these surrogate models, while decreasing drastically the computational cost, may fail in computing an accurate failure probability. In this paper, we focus on the control of the error introduced by a reduced basis surrogate model on the computation of the failure probability obtained by a Monte Carlo simulation. We propose a technique to determine bounds of this failure probability, as well as a strategy of enrichment of the reduced basis, based on limiting the bounds of the error of the failure probability for a multi‐material elastic structure. Copyright © 2017 John Wiley & Sons, Ltd.     

The partition of unity quadrature in meshless methods

In dealing with mesh‐free formulations a major problem is connected to the computation of the quadratures appearing in the variational principle related to the differential boundary value problem. These integrals require, in the standard approach, the introduction of background quadrature subcells which somehow make these methods not ‘truly meshless’. In this paper a new general method for computing definite integrals over arbitrary bounded domains is proposed, and it is applied in particular to the evaluation of the discrete weak form of the equilibrium equations in the framework of an augmented Lagrangian element‐free formulation. The approach is based on splitting the integrals over the entire domain into the sum of integrals over weight function supports without modifying in any way the variational principle or requiring background quadrature cells. The accuracy and computational cost of the technique compared to standard Gauss subcells quadrature are discussed. Copyright © 2002 John Wiley & Sons, Ltd.     

A computationally efficient metamodeling approach for expensive multiobjective optimization

This paper explores a new metamodeling framework that may collapse the computational explosion that characterizes the modeling of complex systems under a multiobjective and/or multidisciplinary setting. Under the new framework, a pseudo response surface is constructed for each design objective for each discipline. This pseudo response surface has the unique property of being highly accurate in Pareto optimal regions, while it is intentionally allowed to be inaccurate in other regions. In short, the response surface for each design objective is accurate only where it matters. Because the pseudo response surface is allowed to be inaccurate in other regions of the design space, the computational cost of constructing it is dramatically reduced. An important distinguishing feature of the new framework is that the response surfaces for all the design objectives are constructed simultaneously in a mutually dependent fashion, in a way that identifies Pareto regions for the multiobjective problem. The new framework supports the puzzling notion that it is possible to obtain more accuracy and radically more design space exploration capability, while actually reducing the computation effort. This counterintuitive metamodeling paradigm shift holds the potential for identifying highly competitive products and systems that are well beyond today’s state of the art.     

A two-scale FE-FFT approach to nonlinear magneto-elasticity

Fourier-based approaches are a well-established class of methods for the theoretical and computational characterization of microheterogeneous materials. Driven by the advent of computational homogenization techniques, Fourier schemes gained additional momentum over the past decade. In recent contributions, the interpretation of Green operators central to Fourier solvers as projections opened up a new perspective. Based on such a viewpoint, the present work addresses a multiscale framework for magneto-mechanically coupled materials at finite strains. The key ingredient for the solution of magneto-mechanic boundary value problems at the microscale is the construction of suitable operators in Fourier space that project vector fields onto either curl-free or divergence-free subspaces. The resulting linear system of equations is solved by a conjugate gradient method. In addition to that, we describe the computation of the consistent macroscopic tangent operator based on the same linear operators as the microscopic equilibrium with appropriately defined right-hand sides. We employ the framework for the simulation of representative two-scale boundary value problems and compare the results with pure finite element schemes.