对象映射关系型数据库技术研究

Object Relationship Mapping(简称ORMapping)是将数据库表映射为面向对象系统中的类,表中的每一条记录则对应为该类的一个具体对象的技术。通过这种技术,可以在软件开发的过程中采用面向对象的方式来处理与数据库相关的部分,比如记录的增加、修改、删除等。讨论了实现OKMapping的几个关键性技术要点,数据库表字段映射对象属性,数据库操作映射面向对象操作,数据库主键外键关联映射对象之间的关系,映射对象如何来适应表结构的变化,事务管理。讨论了ORMapping的性能问题。     

Simulation-based fully Bayesian experimental design for mixed effects models

Bayesian inference has commonly been performed on nonlinear mixed effects models. However, there is a lack of research into performing Bayesian optimal design for nonlinear mixed effects models, especially those that require searches to be performed over several design variables. This is likely due to the fact that it is much more computationally intensive to perform optimal experimental design for nonlinear mixed effects models than it is to perform inference in the Bayesian framework. Fully Bayesian experimental designs for nonlinear mixed effects models are presented, which involve the use of simulation-based optimal design methods to search over both continuous and discrete design spaces. The design problem is to determine the optimal number of subjects and samples per subject, as well as the (near) optimal urine sampling times for a population pharmacokinetic study in horses, so that the population pharmacokinetic parameters can be precisely estimated, subject to cost constraints. The optimal sampling strategies, in terms of the number of subjects and the number of samples per subject, were found to be substantially different between the examples considered in this work, which highlights the fact that the designs are rather problem-dependent and can be addressed using the methods presented.     

一种XML Schema和ontology间的语义映射算法

语义映射是信息集成的重要基础．提出了一种XML Schema和ontology间的语义映射算法,该算法引入了模式图模型,通过该模型计算概念闽的词义匹配度和概念上下文匹配度的加权来计算概念间的相似度,以判断概念是否匹配,实验结果表明,该算法是有效的,能够匹配XSD、WSDL文档和ontology的相应概念.     

Feature-based design and material blending for free-form heterogeneous object modeling

In this paper, a new feature-based method is proposed to represent and design heterogeneous objects. Material governing features are defined to control material composition inside the objects. Interrelations between the material governing features and material attributes are established in the design process and retained in the object model. Free-form B-spline functions are used to represent complex shapes of geometry and material features. A new material feature blending method is used to determine continuous material variation. To obtain the best material features, an optimization problem is constructed based on the object's functional requirements. Variant models are easily generated by changing the geometric and material features using the constraints between them. Implementation and examples are also presented in this paper.     

ONet对象数据库对象组件的改进和实现

面向对象数据库系统ONet遵循了对象数据库标准ODMG3.0,实现了其中C 语言绑定的部分.介绍了目前ONet系统客户端基本结构,分析了客户端使用流程中静态绑定对象模式的缺陷,针对性地提出一种基于动态对象组件的设计方法,详细阐述了运用接口编程,以及组件间的回调技术对现有系统架构进行改进和拆分的方案,使ONet系统最终实现了对象模式的动态加载.     

Schema manipulation in self-describing and self-documenting data models

This paper integrates data, schema and meta-schema into a uniform model and provides one data language to manipulate and modify both data and schema. The modifications on the schema are then propagated to the schema's extension via propagation rules. The integration and the schema modification are all developed within the framework of self-describing and self-documenting models of data and they are fundamental in capturing the evolution of the database, which includes not only data changes, but schema changes as well.This work has been partially supported by NASA under contract NAS 5-26810.     

带纹理映射的牙膏体构造法及其OpenGL实现

在探讨三维Morphing(形状过渡)技术的基础上,提出了一种带不失真纹理映射的牙膏体构造法,较详尽地阐述了三角网格剖分算法的思想.牙膏体是一个包含帽体和膏体两部分的复杂曲面体,从顶部圆台过渡到中间圆面、最后过渡到底部一条直线,它们在拓扑结构上是同构的,因此能通过OpenGL的顶点数组编程加以实现.这种组合曲面造型法不仅方便,还提供丰富的参数选择,具有一定的应用意义,也能有效应用于二维半形状、火箭体和鱼类等绘制.     

对象概念模式及其数据库技术研究

在 E- R分析、语义对象模型和关系数据库的基础上 ,主要结合面向对象方法和数据库特种技术以及笔者在数据库编程方面的实践经验 ,提出了数据库对象概念模式 ,讨论了其中的主要概念 ,并在此模式上重新定义或说明了一些重要的数据库操作 ,如对象集合、时态数据库、多维分析等等     

MIDS／BUAA的模式管理器与对象管理器的设计

本文首先回顾了ＭＩＤＳ／ＢＵＡＡ总体设计中相关的部分重要内容，ｕｎｉｖＯｂｊｅｃｔ对象定义，持久性规则、库模式和ＭＩＤＳ的功能构成等。然后重点介绍了ＭＩＤＳ／ＢＵＡＡ中两个核心模块；模式管理器ＳＭ和对象管理器ＯＭ的思想，基本任务和实现途径；最后给出了ＭＩＤＳ／ＢＵＡＡ类库的层次结构。     

Supporting the reconciliation of models of object behaviour

This paper presents Reconciliation+, a method which identifies overlaps between models of software systems behaviour expressed as UML object interaction diagrams (i.e., sequence and/or collaboration diagrams), checks whether the overlapping elements of these models satisfy specific consistency rules and, in cases where they violate these rules, guides software designers in handling the detected inconsistencies. The method detects overlaps between object interaction diagrams by using a probabilistic message matching algorithm that has been developed for this purpose. The guidance to software designers on when to check for inconsistencies and how to deal with them is delivered by enacting a built-in process model that specifies the consistency rules that can be checked against overlapping models and different ways of handling violations of these rules. Reconciliation+ is supported by a toolkit. It has also been evaluated in a case study. This case study has produced positive results which are discussed in the paper.     

A systematic mapping study of gamification models oriented to motivational characteristics

ABSTRACT

Context: Gamification focuses on the improvement of users' engagement when performing tasks by making use of game mechanics and elements in order to increase their motivations. Many researches have developed gamification models supporting a variety of motivational characteristics to provide engagement solutions for different areas. Objective: This paper carries out a systematic mapping in the field of gamification, looking for models with motivational characteristics in an attempt to characterise the state of the art of this field, identifying gaps and tendencies for further research. Method: We carried out a systematic mapping aiming at finding the primary studies in the existing literature, which were later classified and analysed according to twelve criteria. Results: We analysed 70 papers that resulted in 17 primary studies, published until September 2016. Most of them focus on Education, making use of Gamification to increase the motivation of a learning process. The gamification mechanics and elements most used were Badges/Achievements and Points/ExperiencePoints(XP), and most of the studies were not validated, thus not providing empirical evidence of the impact of gamification. Conclusions: Existing research in the field is somehow preliminary, and more research effort to analyse the applicability of the models and their respective evaluations would be needed.     

Online learning and fusion of orientation appearance models for robust rigid object tracking

We introduce a robust framework for learning and fusing of orientation appearance models based on both texture and depth information for rigid object tracking. Our framework fuses data obtained from a standard visual camera and dense depth maps obtained by low-cost consumer depth cameras such as the Kinect. To combine these two completely different modalities, we propose to use features that do not depend on the data representation: angles. More specifically, our framework combines image gradient orientations as extracted from intensity images with the directions of surface normals computed from dense depth fields. We propose to capture the correlations between the obtained orientation appearance models using a fusion approach motivated by the original Active Appearance Models (AAMs). To incorporate these features in a learning framework, we use a robust kernel based on the Euler representation of angles which does not require off-line training, and can be efficiently implemented online. The robustness of learning from orientation appearance models is presented both theoretically and experimentally in this work. This kernel enables us to cope with gross measurement errors, missing data as well as other typical problems such as illumination changes and occlusions. By combining the proposed models with a particle filter, the proposed framework was used for performing 2D plus 3D rigid object tracking, achieving robust performance in very difficult tracking scenarios including extreme pose variations.     

Generic object recognition with regional statistical models and layer joint boosting

This paper presents novel regional statistical models for extracting object features, and an improved discriminative learning method, called as layer joint boosting, for generic multi-class object detection and categorization in cluttered scenes. Regional statistical properties on intensities are used to find sharing degrees among features in order to recognize generic objects efficiently. Based on boosting for multi-classification, the layer characteristic and two typical weights in sharing-code maps are taken into account to keep the maximum Hamming distance in categories, and heuristic search strategies are provided in the recognition process. Experimental results reveal that, compared with interest point detectors in representation and multi-boost in learning, joint layer boosting with statistical feature extraction can enhance the recognition rate consistently, with a similar detection rate.     

一种基于对象技术的协同设计方法

研究了虚拟样机概念设计中多用户并发设计的信息存储与设计信息表示,针对最常用的STEP数据交换标准,提出了基于对象的设计信息融合及冲突检测与解决机制,并给出了这项技术在某导弹武器系统总体概念多用户协同设计中的作用。     

A graph mining approach for detecting identical design structures in object-oriented design models

The object-oriented approach has been the most popular software design methodology for the past twenty-five years. Several design patterns and principles are defined to improve the design quality of object-oriented software systems. In addition, designers can use unique design motifs that are designed for the specific application domains. Another commonly used technique is cloning and modifying some parts of the software while creating new modules. Therefore, object-oriented programs can include many identical design structures. This work proposes a sub-graph mining-based approach for detecting identical design structures in object-oriented systems. By identifying and analyzing these structures, we can obtain useful information about the design, such as commonly-used design patterns, most frequent design defects, domain-specific patterns, and reused design clones, which could help developers to improve their knowledge about the software architecture. Furthermore, problematic parts of frequent identical design structures are appropriate refactoring opportunities because they affect multiple areas of the architecture. Experiments with several open-source and industrial projects show that we can successfully find many identical design structures within a project (intra-project) and between different projects (inter-project). We observe that usually most of the detected identical structures are an implementation of common design patterns; however, we also detect various anti-patterns, domain-specific patterns, reused design parts and design-level clones.     

泛关系模式的规范化处理及其实例研究

通过对泛关系理论的分析与研究,提出一种基于泛关系模式的自底向上（Bottom-Up）关系数据库规范化设计方法,利用规范化设计理论,通过模式分解,逐步消除数据依赖中不合适的部分,消除各类操作异常,减少数据的冗余。关键词：泛关系模式;规范化;模式分解     

Adaptive thread mapping strategies for transactional memory applications

Transactional Memory (TM) is a programmer friendly alternative to traditional lock-based concurrency. Although it intends to simplify concurrent programming, the performance of the applications still relies on how frequent they synchronize and the way they access shared data. These aspects must be taken into consideration if one intends to exploit the full potential of modern multicore platforms. Since these platforms feature complex memory hierarchies composed of different levels of cache, applications may suffer from memory latencies and bandwidth problems if threads are not properly placed on cores. An interesting approach to efficiently exploit the memory hierarchy is called thread mapping. However, a single fixed thread mapping cannot deliver the best performance when dealing with a large range of transactional workloads, TM systems and platforms. In this article, we propose and implement in a TM system a set of adaptive thread mapping strategies for TM applications to tackle this problem. They range from simple strategies that do not require any prior knowledge to strategies based on Machine Learning techniques. Taking the Linux default strategy as baseline, we achieved performance improvements of up to 64.4% on a set of synthetic applications and an overall performance improvement of up to 16.5% on the standard STAMP benchmark suite.