The use of object-oriented database principles to help model an image for computer vision, specifically, for line-image analysis, is described. The resulting representation, called thin line code (TLC), is general acr...
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The use of object-oriented database principles to help model an image for computer vision, specifically, for line-image analysis, is described. The resulting representation, called thin line code (TLC), is general across known applications and extensible to new applications. TLC's advantages, and also some difficulties it has in strictly adhering to traditional notions of object orientation, are addressed. A review of relevant aspects of object modeling is included
Some solutions to a programming problem are more elegant or more simple than others and thus more understandable for students. We review desirable properties of example programs from a cognitive and a measurement poin...
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Some solutions to a programming problem are more elegant or more simple than others and thus more understandable for students. We review desirable properties of example programs from a cognitive and a measurement point of view. Certain cognitive aspects of example programs are captured by common software measures, but they are not sufficient to capture a key aspect of understandability: readability. We propose and discuss a simple readability measure for software, SRES, and apply it to object-oriented textbook examples. Our results show that readability measures correlate well with human perceptions of quality. Compared with other readability measures, SRES is less sensitive to commenting and whitespace. These results also have implications for software maintainability measures.
Discussed in this paper is a novel method for the generation of Jacobian matrices which is particularly suitable for object-oriented implementations of multibody dynamics programs. The method starts from a description...
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Discussed in this paper is a novel method for the generation of Jacobian matrices which is particularly suitable for object-oriented implementations of multibody dynamics programs. The method starts from a description of multibody kinematics as a series of general mappings between manifolds, from which the overall Jacobian results-via the chain rule-as a sequence of matrix products. For these matrices, a new sparse-matrix scheme is suggested. Their "elements" are, besides zeroes, the well-known spatial transformation matrices and the local Jacobians of the individual transmission elements. It is shown how the main approaches for calculation of Jacobians in robotics can be viewed as particular decompositions and multiplication schemes of the sparse-matrices discussed above. Furthermore, two new schemes are derived which may be advantageous for dynamics calculations. The exposition is complemented by a comparison of Jacobian-based methods with composite rigid body and recursive methods for the generation of dynamical equations together with some comments on our current C++-implementation.
This paper gives an overview of the development of a distributed object-oriented kernel implemented in Modula-2. The underlying concepts of this kernel are first described. Its main feature consists in using task migr...
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This paper gives an overview of the development of a distributed object-oriented kernel implemented in Modula-2. The underlying concepts of this kernel are first described. Its main feature consists in using task migration in order to achieve communication between distant nodes of the local network. Then, the implementation in Modula-2 is outlined. We emphasise the use of modules for implementing kernel objects and types. We conclude by evaluating the Modula-2 language through this experience.
The recent trend in distributed automation and control systems has been towards event-triggered system architectures such as UML and IEC 61499. Although existing communication protocols (e.g., Ethernet) can support hi...
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The recent trend in distributed automation and control systems has been towards event-triggered system architectures such as UML and IEC 61499. Although existing communication protocols (e.g., Ethernet) can support high-level communication within these systems, there is contention as to which low-level protocol to use, or if any exist that meet the requirements of being event-triggered and hard real-time. This paper proposes a new way to measure communication performance. The goal of the new measurement method is to stress the necessity that a real-time communication protocol needs to be both efficient and fair. This is illustrated by comparing three communication strategies: Controller Area Network (CAN), Time-Triggered CAN (TTCAN) and Escalating Priority CAN (EPCAN). The first two represent the extremes between event-triggered and time-triggered communication strategies;the third is introduced to illustrate the benefits of a new event-based communication protocol proposed by the authors. (c) 2010 Elsevier Ltd. All rights reserved.
Software faults are costly to find and remove from programs. It is better to avoid inserting the faults in the first place. The authors identify requirements-related faults that can arise during the transformation of ...
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Software faults are costly to find and remove from programs. It is better to avoid inserting the faults in the first place. The authors identify requirements-related faults that can arise during the transformation of formal specifications into programs, analyse each to discover its causes, and propose corresponding fault prevention methods. The approach works by analysing a specification, decomposing it into specification fragments with different levels like components, determining the correct implementation order among the components, and enabling automated code generation for the components and other low-level specification fragments. The approach seeks to reduce the faults in programs significantly by guiding programmers to work effectively and productively. The authors evaluate the approach's performance experimentally and compare it to the performance of a fault-prevention method with industry applications.
This paper presents the development of an event-driven control architecture and its implementation in a physical simulator of a computerized manufacturing system using object-oriented techniques. The architecture was ...
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This paper presents the development of an event-driven control architecture and its implementation in a physical simulator of a computerized manufacturing system using object-oriented techniques. The architecture was developed to improve the efficiency of handling concurrent control events in the DOS environment. In the implementation, the control system of the physical simulator consists of four distinct layers of control devices: a PC/386 computer, a microcontroller, I/O modules and the system's control devices such as motors, solenoids and sensors. A control program residing in the PC/386 coordinates system-level tasks such as event scheduling, while a BASIC program running on the microcontroller handles all low-level control tasks such as sensor monitoring and motion control. The concepts and developments presented in this paper should help in implementing an efficient control system for both CIM systems and their physical simulators.
The paper describes a detailed study into the object-oriented implementation of distributed finite element analysis on desktop computers using the NET framework. The software design aspects are described in some detai...
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The paper describes a detailed study into the object-oriented implementation of distributed finite element analysis on desktop computers using the NET framework. The software design aspects are described in some detail for both direct and iterative solution algorithms. The use of interfaces played an important role in the software design. This, together with the NET framework, enabled remote objects to be implemented in a relatively seamless fashion. The solution routines were "blind" to whether the objects were local or remote. Numerical tests were carried out and reasonable speed-up was achieved, particularly for direct solution methods. It is concluded that NET provides a viable framework for implementing distributed computing on networks of personal computers. (c) 2006 Elsevier Ltd. and Civil-Comp Ltd. All rights reserved.
The aim of the paper is to investigate applicability of object-oriented software design patterns in the context of aspect-oriented design. The paper analyses which of the GoF 23 patterns have a meaning in this context...
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The aim of the paper is to investigate applicability of object-oriented software design patterns in the context of aspect-oriented design. The paper analyses which of the GoF 23 patterns have a meaning in this context and how they are affected by it. The main assumption is that there exist design patterns that solve software engineering paradigm independent design problems and that such patterns, in the contrast to the patterns solving paradigm-specific design problems, can be expressed in terms of any software engineering paradigm. However, the paper deals only with two paradigms: aspect-oriented (AO) paradigm and object-oriented (OO) paradigm. It proposes a classification of design problems based on this assumption and a technique for redesigning object-oriented patterns into pure aspect-oriented ones. It presents a number of examples how to apply this technique and discusses the results obtained. The results show that 20 of the GoF 23 design patterns solve such design problems that are common at least for both mentioned paradigms and demonstrate in which way these patterns can be adapted for the needs of aspect-oriented design.
作者：
Deng, LiangZeng, QingkaiNanjing Univ
State Key Lab Novel Software Technol Nanjing 210023 Jiangsu Peoples R China Nanjing Univ
Dept Comp Sci & Technol Nanjing 210023 Jiangsu Peoples R China
Commodity operating system kernels are vulnerable to a wide range of attacks due to the large code base and broad attack surface. Mitigation mechanisms such as code signing, W circle plus X, and code integrity protect...
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Commodity operating system kernels are vulnerable to a wide range of attacks due to the large code base and broad attack surface. Mitigation mechanisms such as code signing, W circle plus X, and code integrity protection have raised the bar for kernel security. In turn, attack mechanisms have also become increasingly advanced. They have evolved from simple injection of malicious code into more sophisticated code-reuse attacks [e.g. return-orientedprogramming (ROP)]. In this study, the authors describe exception-orientedprogramming (EOP), a novel code-reuse method to construct kernel malware. Unlike previous ROP that can only reuse a limited part of existing code (gadgets), EOP is able to reuse any instruction in existing code and chain the instructions in any order to generate malicious programmes. As a result, EOP can provide the attackers with more powerful capabilities and less complexity for building kernel malware.
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