Aperiodic structures in optics and integrated optics and the transverse Bragg reflector laser

The first part of this work describes the uses of aperiodic structures in optics and integrated optics. In particular, devices are designed, fabricated, tested and analyzed which make use of a chirped grating corrugation on the surface of a dielectric waveguide. These structures can be used as input-output couplers, multiplexers and demultiplexers, and broad band filters.

Next, a theoretical analysis is made of the effects of a random statistical variation in the thicknesses of layers in a dielectric mirror on its reflectivity properties. Unlike the intentional aperiodicity introduced in the chirped gratings, the aperiodicity in the Bragg reflector mirrors is unintentional and is present to some extent in all devices made. The analysis involved in studying these problems relies heavily on the coupled mode formalism. The results are compared with computer experiments, as well as tests of actual mirrors.

The second part of this work describes a novel method for confining light in the transverse direction in an injection laser. These so-called transverse Bragg reflector lasers confine light normal to the junction plane in the active region, through reflection from an adjacent layered medium. Thus, in principle, it is possible to guide light in a dielectric layer whose index is lower than that of the surrounding material. The design, theory and testing of these diode lasers are discussed.

五自由度纳米级定位工作台的设计研究

提出一种新型的五自由度精密定位平台的工作原理及其设计方法。工作台采用柔性导向机构实现平移及转动功能，采用压电陶瓷作为驱动元件，外置纳米级电容传感器作为位移量测量反馈元件，采用数字PID控制方法，可以实现纳米级精度的定位。给出了多种形式柔性导向机构刚度计算公式及设计实例。

Tipografia pintada no Centro do Rio de Janeiro

Esta pesquisa tem como objetivo analisar a tipografia pintada no centro da cidade do Rio de Janeiro. A escolha da área de pesquisa busca mensurar a importância da pintura manual como técnica de produção de elementos tipográficos na paisagem urbana de um bairro central de uma grande cidade, bem como a situação atual do ofício dos pintores de letras, principais responsáveis pela sua produção. Foi realizado um levantamento fotográfico extensivo por toda área, assim como uma série de entrevistas com os pintores. Uma revisão bibliográfica buscou identificar onde outros trabalhos dessa natureza são contextualizados à luz da teoria do design, principalmente através da investigação do vernacular como categoria analítica. Foram buscadas referências históricas relacionadas ao ofício da pintura de letras, a fim de comparações com o discurso dos pintores atuais, do qual foram apropriados elementos que, juntamente com a teoria do design e da tipografia, foram utilizados para a construção de um sistema de análise, que incluiu entre suas diretrizes a produção de dados quantitativos que permitam identificar os recursos mais recorrentes que constituem a linguagem gráfica pesquisada.

A framework for designing product service systems

In this competitive globalizing scenario, manufacturers are adopting a strategy of bundling products and services into an integrated solution to create sustainable competitive advantage. Servitizing manufacturers are increasingly transforming their processes and practices to build product-service systems (PSS). During this transformation they require substantial support to face stringent challenges. Research in the PSS domain is heading towards the development of a design theory and methodology that facilitates the systematic creation of viable PSS conceptual designs. In this paper, various proposed design methods are reviewed and research gaps are summarized. Primarily, it has been observed that the importance of the capabilities of the stakeholders involved in designing PSS has not been noted in the proposed methods. Regarding this capability view point, a framework for designing PSS has been proposed. This framework highlights the important features required in designing PSS such as co-creation, responsibilities and competences. Every step in the framework has been explained with a case study involving laser systems used for manufacturing cutting operation.

Function propagation through nested systems

Concepts of function are central to design but statements about a device's functions can be interpreted in different ways. This raises problems for researchers trying to clarify the foundations of design theory and for those developing design support-tools that can represent and reason about function. By showing how functions relate systems to their sub-systems and super-systems, this article illustrates some limitations of existing function terminology and some problems with existing function statements. To address these issues, a system-relative function terminology is introduced. This is used to demonstrate that systems function not only with respect to their most local super-system, but also with respect to their more global super-systems. © 2012 Elsevier Ltd. All rights reserved.

并联结构制造装备设计理论与建模方法研究

并联结构制造装备（Parallel Kinematic Machine简称PKM）是近年发展起来的一种新型制造装备，它以承载能力强、动态性能好、刚度重量比大等优点而受到广大学者及机床制造商的重视并正在成为制造领域的一个研究热点。本文就有关PKM的结构、位置分析、速度关系、工作空间分析、奇异位形分析以及标定方法等问题进行了深入的研究，具体内容包括以下几个方面：1．根据现有PKM的结构特点，将它们划分为“腿伸缩”的6条腿结构、“腿滑动’夕的6条腿结构、“腿伸缩”的3条腿结构、“腿滑动”的3条腿结构等类型，这种划分佩方面能够较准确地反映PK.M的结构特征以及复杂程度，另一方面也易于为广大工程技术人员理解和使用。2．将少自由度并联机构分为满阶机构以及欠阶机构，而欠阶机构又进一步分为非期望输出为常量和非期望输出为变量两种类型，这样的分类反映了机构的本质特征以及对其进行研究的复杂程度。3．提出利用演化关系研究各种典型并联机构之间的内在联系，建立了一些典型并联机构之间的演化关系，为利用演化关系进行并联机构的运动学性能分析奠定了基础。根据演化原理，提出了几种实现两维平动、两维转动的4自由度 (2T-2R, 4-DOF）并联机构新构型，并用杆一副关系图进行描述。4．基于机构演化关系建立了典型并联机构位置分析数学描述的统一表达形式，并对所提出的几种2T-2R, 4-DOF并联机构的位置正、逆解进行了详细的讨论。对并联机构速度、静力传递关系的对偶性以及串联与并联之间的对偶关系进行了总结。5．提出具有灵巧度指标要求的适用工作空间概念，对考虑灵巧度指标要求的全姿态工作空间的确定进行了详细分析，给出了几种机构工作空间求解的具体结果。分析了现有奇异位形分析方法应用于少自由度并联机构时可能会出现的问题，并基于前面所述机构演化关系，提出一种进行少自由度并联机构奇异位形分析的新途径。6.分析了PKM运动学标定的研究现状，提出了一种新的运动学参数识别方法。该方法利用运动学逆解模型建立目标函数，并且不需要测量运动平台的姿态参数。7.初步完成了一个适用于PKM的基于“IPC+PMAC”的双CPU开放式数控系统的开发。对于不同构型的PKM，可以方便地更换虚实空间映射模块，并方便地扩展各种新的功能模块。通过本文的工作，对并联结构制造装备的若干问题进行了系统的研究，为新型并联结构制造装备研究和走向工程应用提供了设计思想、建模方法和关键技术，对于推进并联结构制造装备的发展具有重要意义。

The use of ICT in the course “Photography” in university education. First results of a teaching innovation project at the University of Murcia

The new pedagogical framework arisen since the Bologna Declaration,the Prague Communiquéand the introduction of the European Higher Education Area (EHEA), encourages, significantly, the use of new Communication and Information Technology to evolve teaching methodologies. The different ways teachers relate to learners have undergone a staggering change from which educational initiatives have emerged. Many of them are based on contents’ democratization through the use of ICT. The current article is intended to show the results obtained until the 2012/2013 academic course, since the implementation of the teaching innovation project entitled “The use of ICT for the students’ autonomous learning in the university education of the course Photography. Elaboration of a virtual classroom and results’ analysis related to the acquisition of skills and competencies” that has been developed in the course called Draw with light: Photography, belonging to the Fine Arts Degree at the University of Murcia.

Pull-out forces in shear connectors in composite beams with large web openings

Composite beams with large web openings are often used, and their design is controlled by Vierendeel bending at the four corners of each opening, which is assisted by local composite action with the floor slab. Development of this Vierendeel bending resistance may be limited by pull-out failure of the shear connectors. In this paper, a non-linear elasto-plastic finite element model of a composite beam with web openings was used to investigate this mode of pull-out failure. A test was performed on a typical composite slab in which the shear connectors were subject to pure tension and the failure load was 67 kN, which is approximately 70% of the longitudinal shear resistance. The results of the finite element model are compared against those obtained using the established design theory, that does not limit the vertical pull-out resistance of the shear connectors. It is shown that the local bending resistance due to composite action should be reduced when limited by pull-out of the shear connectors. A parametric study investigated the effect of openings of 600 to 1200 mm length. A simple model is developed to establish the Vierendeel bending resistance, when limited by pull-out of the shear connectors.

Construction of I-Deletion-Correcting Ternary Codes

Finding large deletion correcting codes is an important issue in coding theory. Many researchers have studied this topic over the years. Varshamov and Tenegolts constructed the Varshamov-Tenengolts codes (VT codes) and Levenshtein showed the Varshamov-Tenengolts codes are perfect binary one-deletion correcting codes in 1992. Tenegolts constructed T codes to handle the non-binary cases. However the T codes are neither optimal nor perfect, which means some progress can be established. Latterly, Bours showed that perfect deletion-correcting codes have a close relationship with design theory. By this approach, Wang and Yin constructed perfect 5-deletion correcting codes of length 7 for large alphabet size. For our research, we focus on how to extend or combinatorially construct large codes with longer length, few deletions and small but non-binary alphabet especially ternary. After a brief study, we discovered some properties of T codes and produced some large codes by 3 different ways of extending some existing good codes.

Reinforcement Learning by Policy Search

One objective of artificial intelligence is to model the behavior of an intelligent agent interacting with its environment. The environment's transformations can be modeled as a Markov chain, whose state is partially observable to the agent and affected by its actions; such processes are known as partially observable Markov decision processes (POMDPs). While the environment's dynamics are assumed to obey certain rules, the agent does not know them and must learn. In this dissertation we focus on the agent's adaptation as captured by the reinforcement learning framework. This means learning a policy---a mapping of observations into actions---based on feedback from the environment. The learning can be viewed as browsing a set of policies while evaluating them by trial through interaction with the environment. The set of policies is constrained by the architecture of the agent's controller. POMDPs require a controller to have a memory. We investigate controllers with memory, including controllers with external memory, finite state controllers and distributed controllers for multi-agent systems. For these various controllers we work out the details of the algorithms which learn by ascending the gradient of expected cumulative reinforcement. Building on statistical learning theory and experiment design theory, a policy evaluation algorithm is developed for the case of experience re-use. We address the question of sufficient experience for uniform convergence of policy evaluation and obtain sample complexity bounds for various estimators. Finally, we demonstrate the performance of the proposed algorithms on several domains, the most complex of which is simulated adaptive packet routing in a telecommunication network.

Asymmetrically fair rules for an indivisible good problem with a budget constraint

We study a particular restitution problem where there is an indivisible good (land or property) over which two agents have rights: the dispossessed agent and the owner. A third party, possibly the government, seeks to resolve the situation by assigning rights to one and compensate the other. There is also a maximum amount of money available for the compensation. We characterize a family of asymmetrically fair rules that are immune to strategic behavior, guarantee minimal welfare levels for the agents, and satisfy the budget constraint.

Contribución metodológica en técnicas de diseñar para fabricación

En el proceso de diseño se toman decisiones que pueden afectar a la fabricabilidad del producto. Cuando el diseñador es experto, considera las limitaciones, las propiedades y el coste de fabricación en la fase de materialización o de detalle. El problema surge cuando el diseñador no es experto o cuando no hay suficiente información y conocimiento de fabricación disponible. Tomando como referencia la teoría de Diseño Axiomático y las técnicas de DFM, se propone una metodología para identificar, definir y formalizar la información de fabricación que debería estar disponible en el diseño para diseñar para fabricar (DFM). También se propone un prototipo de modelo de información para desarrollar una futura herramienta informática que facilitaría la aplicación de esta metodología y que permitiría guiar al diseñador durante el diseño. La metodología ha sido aplicada a una biela de un motor de combustión interna alternativo (MCIA), y a los procesos que se están usando actualmente para fabricarla: forja en matriz cerrada y forja de polvo de metal.