自动对焦显微镜系统设计及仿真

设计了一种基于条纹投影的自动对焦显微镜系统。通过红外光源将光栅掩膜板投射到被测物表面,用于对焦判断。通过白光光源进行系统照明。使用带通滤光片分离出由红外光源投射的光栅像,并由线阵CCD采集,用于离焦量和离焦方向的判断。由白光光源照射得到被测物的像,并由面阵CCD接受用于直接观测。使用Tracepro对设计的系统进行仿真,分析得到适用于线阵CCD采集的光栅图的一维清晰度评价函数,并使用系统对不同被测物进行仿真对焦实验与误差分析。仿真结果表明,本系统可对不同被测物进行自动对焦。     

Conceptual design of aeroelastic structures by topology optimization

A topology optimization methodology is presented for the conceptual design of aeroelastic structures accounting for the fluid–structure interaction. The geometrical layout of the internal structure, such as the layout of stiffeners in a wing, is optimized by material topology optimization. The topology of the wet surface, that is, the fluid–structure interface, is not varied. The key components of the proposed methodology are a Sequential Augmented Lagrangian method for solving the resulting large-scale parameter optimization problem, a staggered procedure for computing the steady-state solution of the underlying nonlinear aeroelastic analysis problem, and an analytical adjoint method for evaluating the coupled aeroelastic sensitivities. The fluid–structure interaction problem is modeled by a three-field formulation that couples the structural displacements, the flow field, and the motion of the fluid mesh. The structural response is simulated by a three-dimensional finite element method, and the aerodynamic loads are predicted by a three-dimensional finite volume discretization of a nonlinear Euler flow. The proposed methodology is illustrated by the conceptual design of wing structures. The optimization results show the significant influence of the design dependency of the loads on the optimal layout of flexible structures when compared with results that assume a constant aerodynamic load.     

Parallel algorithm for calculation of the exact partition function of a lattice polymer

We develop a parallel algorithm that calculates the exact partition function of a lattice polymer, by enumerating the number of conformations for each energy level. An efficient parallelization of the calculation is achieved by classifying the conformations according to the shape of the box spanned by a conformation, and enumerating only those in a given box at a time. The calculation time for each box is reduced by preventing the conformations related by symmetries from being generated more than once. The algorithm is applied to study the collapse transition of a lattice homopolymer on a square lattice, by calculating the specific heat for chain lengths up to 36.     

Solutions of equations in languages

A context-free grammar corresponds to a system of equations in languages. The language generated by the grammar is the smallest solution of the system. We give a necessary and sufficient condition for an arbitrary solution to be the smallest one. We revive an old criterion to decide that a grammar has a unique solution. All this fits in an approach to search for a grammar for an arbitrary language that is given by other means. The approach is illustrated by the derivation of a grammar for a certain set of bit strings. The approach is used to give an elegant derivation of the grammar for a language accepted by a pushdown automaton.     

Optimization-based computation of analytic interpolants of bounded complexity

This paper provides a unifying algorithm for computing any analytic interpolant of bounded complexity. Such computation can be performed by solving an optimization problem, due to a theorem by Georgiou and Lindquist. This optimization problem is numerically solvable by a continuation method. The proposed numerical algorithm is useful, among other cases, for designing a low-degree controller for a benchmark problem in robust control. The algorithm unifies previously developed algorithms for the Carathéodory extension and the Nevanlinna–Pick interpolation to one for more general interpolation problems.     

Modeling and simulation of an artificial muscle and its application to biomimetic robot posture control

The shape memory effect exhibited by Nitinol wire can be utilized to construct an artificial muscle. The muscle is activated by an electric current, which produces heat and initiates a phase transformation. The Nitinol artificial muscle stress–strain–power relationship was determined by experiments, and a mathematical model was developed. The artificial muscle model was utilized for the posture control of a biomimetic underwater robot. The optimal activation patterns for height, pitch, and roll postures were determined. Simulation results for the height postures are in agreement with the experiments. The separation between the center of gravity and the centroid of the robot has a stabilizing effect on pitch and roll postures.     

Highly serial architecture for a microprocessor

The paper describes the derivation of an architecture for a microcomputer intended for educational applications. The derivation of the microprogrammable architecture given is followed by one possible instruction set and format of the computer for the user. The microinstructions and their sequence that achieve this view for the user are described in some detail. The architecture is fluid and not only is the microinstruction sequence defined by programmable elements but also a programmable element defines the meanings of the microinstructions and many of the interconnections within the processor. Wherever possible steps have been taken to minimize chip area usually by sacrificing parallel for serial operation.     

A Knowledge Engineering Framework for Intelligent Retrieval of Legal Case Studies

Juris-Data is one of the largest case-study base in France. The case studies are indexed by legal classification elaborated by the Juris-Data Group. Knowledge engineering was used to design an intelligent interface for information retrieval based on this classification. The aim of the system is to help users find the case-study which is the most relevant to their own.The approach is potentially very useful, but for standardising it for other legal document bases it is necessary to extract a legal classification of the primary documents. Thus, a methodology for the construction of these classifications was designed together with a framework for index construction. The project led to the implementation of a Legal Case Studies Engineering Framework based on the accumulated experimentation and the methodologies designed. It consists of a set of computerised tools which support the life-cycle of the legal document from their processing by legal experts to their consultation by clients.     

并行文件系统集中式元数据管理高可用系统设计

本文针对并行文件系统集中式元数据管理存在单一失效点的问题，设计了一种双元服务器高可用系统。通过元数据镜像生成冗余副本，保证了元数据的可靠性；通过故障屏蔽，实现了对客户端的连续服务。所有功能都是用内核模块来实现，因此对用户是完全透明的。最后，本文阐述了各个模块的实现，并对该系统进行了可靠性分析。     

Evolution of regulation errors in the diffusion layer in electrodeposition process control

A random field induced by infinitely many noises emerges in numerous processes, such as a mixed boundary electrochemical deposition process, which is determined by the main reaction and several side reactions. Since the process is controlled on one boundary without knowledge of the side reactions, a model error emerges and the regulation error trails. The model considered in this paper allows for general settings and is defined for white noise and colour noise. The white noise is responsible for unpredictable model errors and the colour noise for systematic errors. A relatively simple boundary control is applied that, when lifted into the domain, acts as a smooth function. The paper demonstrates that the regulation error can be suppressed effectively even if the correlation of random noises is relatively weak. The regulation error is suppressed by the double effects of the Laplacian and noise correlation. The traces of covariance operators are found for several categories of the domain noises and for the boundary noises. A similar trace function in general settings satisfies a Kolmogorov equation in infinitely many state variables. The solution for the Kolmogorov equation is simplified to a form that makes numerical treatment possible. The regulation errors induced by white noise are compared with the errors induced by coloured noise in the numerical analysis.     

Measuring and modelling sewer pipes from video

This article presents a system for the automatic measurement and modelling of sewer pipes. The system recovers the interior shape of a sewer pipe from a video sequence which is acquired by a fish-eye lens camera moving inside the pipe. The approach is based on tracking interest points across successive video frames and posing the general structure-from-motion problem. It is shown that the tracked points can be reliably reconstructed despite the forward motion of the camera. This is achieved by utilizing a fish-eye lens with a wide field of view. The standard techniques for robust estimation of the two- and three-view geometry are modified so that they can be used for calibrated fish-eye lens cameras with a field of view less than 180°. The tubular arrangement of the reconstructed points allows pipe shape estimation by surface fitting. Hence, a method for modelling such surfaces with a locally cylindrical model is proposed. The system is demonstrated with a real sewer video and an error analysis for the recovered structure is presented.     

Production of Various Vocal Cord Vibrations Using a Mechanical Model for an Anthropomorphic Talking Robot

We developed a three-dimensional mechanical vocal cord model for Waseda Talker No. 7 (WT-7), an anthropomorphic talking robot, for generating speech sounds with various voice qualities. The vocal cord model is a cover model that has two thin folds made of thermoplastic material. The model self-oscillates by airflow exhausted from the lung model and generates the glottal sound source, which is fed into the vocal tract for generating the speech sound. Using the vocal cord model, breathy and creaky voices, as well as the modal (normal) voice, were produced in a manner similar to the human laryngeal control. The breathy voice is characterized by a noisy component mixed with the periodic glottal sound source and the creaky voice is characterized by an extremely low-pitch vibration. The breathy voice was produced by adjusting the glottal opening and generating the turbulence noise by the airflow just above the glottis. The creaky voice was produced by adjusting the vocal cord tension, the sub-glottal pressure and the vibration mass so as to generate a double-pitch vibration with a long pitch interval. The vocal cord model used to produce these voice qualities was evaluated in terms of the vibration pattern as measured by a high-speed camera, the glottal airflow and the acoustic characteristics of the glottal sound source, as compared to the data for a human.     

CLAUSE MANAGEMENT SYSTEMS (CMS)

This paper provides an extension to the study of the clause management system (CMS) proposed by Reiter and de Kleer. The CMS is adapted specifically for aiding a reasoning system in explanations generation. The reasoning system transmits propositional formulae representing its knowledge to the CMS and in return, it requests the CMS for minimal and consistent explanations of a query with respect to the CMS knowledge base. The CMS knowledge base is represented by a set of prime implicates. The classification of implicates as minimal, prime, trivial, and minimal trivial is carefully examined. Similarly, the notion of a support for a clause including minimal, prime, trivial, and minimal trivial is also elaborated. The methods to compute these supports from implicates and a preference ordering scheme expressible by logical specificity for the set of supports for a given clause are also presented. The generalization of the notion of a minimal support for a conjunction of clauses is also shown. Finally, two logic-based diagnostic reasoning paradigms aided by the CMS are shown to exemplify the functionality of the CMS.     

Human-like fault diagnosis using a neural network implementation of plausibility and relevance

In real systems, fault diagnosis is performed by a human diagnostician, and it encounters complex knowledge associations, both for normal and faulty behaviour of the target system. The human diagnostician relies on deep knowledge about the structure and the behaviour of the system, along with shallow knowledge on fault-to-manifestation patterns acquired from practice. This paper proposes a general approach to embed deep and shallow knowledge in neural network models for fault diagnosis by abduction, using neural sites for logical aggregation of manifestations and faults. All types of abduction problems were considered. The abduction proceeds by plausibility and relevance criteria multiply applied. The neural network implements plausibility by feed-forward links between manifestations and faults, and relevance by competition links between faults. Abduction by plausibility and relevance is also used for decision on the next best test along the diagnostic refinement. A case study on an installation in a rolling mill plant is presented.     

The optimisation of space structures using evolution strategies with functional networks

In this work, the input for large space structures is created using the Formex algebra of the Formian software. The different search and optimisation algorithm known as evolution strategies (ESs) has been applied to find the optimal design of the space trusses considering the areas of the members of the space structures as discrete variables. The objective function is obtained for first few generations by using a structural analysis package such as Feast and for other generations by functional networks (FNs). Initially, to obtain the data for a functional network, a structural package such as Feast is used. The use of a functional network is motivated by time consuming repeated analyses required by evolution strategies during the optimisation process. In addition, a multilevel optimisation approach is implemented by reducing the size of the search space for individual design variables in each successive level of the optimisation process for the first example; for the remaining three examples, a functional network has been combined with evolution strategies to get away with the use of a structural analysis package and a multilevel optimisation technique. The numerical tests presented demonstrate the computational advantage of the proposed approach of ESs combined with functional networks (FNs) which become pronounced for fairly large scale optimisation problems involving about 700 degrees of freedom.     

Boundary integral method for multispecies 1-D convection-diffusion-reaction problems

Boundary integral method has been proposed to solve a system of differential equations with a convection-diffusion operator and a nonlinear rate term for each equation. The operator part can be eliminated by using an inverse formulation by a proper choice of the weighting function for each differential equation. This reduces the problem to an integral formulation which is then solved by approximating the dependent variables by cubic osculation. The method has been demonstrated to a packed bed reactor with heat and mass dispersion and for a countercurrent heat exchanger.     

On the efficiency of categorical combinators as a rewriting system

Categorical combinators form a formal system similar to Curry's combinatory logic. The original system was developed by Curien, inspired by the equivalence of the theories of typed λ-calculus and Cartesian closed categories, as shown by Lambek and Scott. A new system for categorical combinators was introduced by the author. This system uses a more compact notation for the code and needs a smaller set of rewriting rules. The aim of this paper is to analyse these two different rewriting systems for categorical combinators as a basis for implementation of applicative languages, and compare them with the classical approach due to Turner, using combinatory logic.