Surface reflectance adjusted for atmospheric effects is a primary input for land cover change detection and for developing many higher level surface geophysical parameters. With the development of automated atmospheri...
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Surface reflectance adjusted for atmospheric effects is a primary input for land cover change detection and for developing many higher level surface geophysical parameters. With the development of automated atmospheric correction algorithms, it is now feasible to produce large quantities of surface reflectance products using Landsat images. Validation of these products requires in situ measurements, which either do not exist or are difficult to obtain for most Landsat images. The surface reflectance products derived using data acquired by the Moderate Resolution Imaging Spectroradiometer (MOD'S), however, have been validated more comprehensively. Because the MODIS on the Terra platform and the Landsat 7 are only half an hour apart following the same orbit, and each of the 6 Landsat spectral bands overlaps with a MODIS band, good agreements between MODIS and Landsat surface reflectance values can be considered indicators of the reliability of the Landsat products, while disagreements may suggest potential quality problems that need to be further investigated. Here we develop a system called Landsat-MODIS Consistency Checking System (LMCCS). This system automatically matches Landsat data with MODIS observations acquired on the same date over the same locations and uses them to calculate a set of agreement metrics. To maximize its portability, Java and open-source libraries were used in developing this system, and object-oriented programming (OOP) principles were followed to make it more flexible for future expansion. As a highly automated system designed to run as a stand-alone package or as a component of other Landsat data processing systems, this system can be used to assess the quality of essentially every Landsat surface reflectance image where spatially and temporally matching MODIS data are available. The effectiveness of this system was demonstrated using it to assess preliminary surface reflectance products derived using the Global Land Survey (GLS) Landsat i
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.
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.
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.
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.
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.
Simulation-based optimization for industrial process lines is discussed in this paper. Our approach combines multidisciplinary modeling, modern sensitivity analysis methodology as well as multiobjective optimization b...
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Simulation-based optimization for industrial process lines is discussed in this paper. Our approach combines multidisciplinary modeling, modern sensitivity analysis methodology as well as multiobjective optimization by means of object-oriented software design principles. As a result, a simulation and optimization approach that can be extended and modified due to users' needs can be developed. Our approach is illustrated by a real-world example from papermaking industry.
Semantic Web applications share a large portion of development effort with database-driven Web applications. Existing approaches for development of these database-driven applications cannot be directly applied to Sema...
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Semantic Web applications share a large portion of development effort with database-driven Web applications. Existing approaches for development of these database-driven applications cannot be directly applied to Semantic Web data due to differences in the underlying data model. We develop a mapping approach that embeds Semantic Web data into object-oriented languages and thereby enables reuse of existing Web application frameworks. We analyse the relation between the Semantic Web and the Web, and survey the typical data access patterns in Semantic Web applications. We discuss the mismatch between object-oriented programming languages and Semantic Web data, for example in the semantics of class membership, inheritance relations, and object conformance to schemas. We present ActiveRDF, an object-oriented API for managing RDF data that offers full manipulation and querying of RDF data, does not rely on a schema and fully conforms to RDF( S) semantics. ActiveRDF can be used with different RDF data stores: adapters have been implemented to generic SPARQL endpoints, Sesame, Jena, Redland and YARS and new adapters can be added easily. We demonstrate the usage of ActiveRDF and its integration with the popular Ruby on Rails framework which enables rapid development of Semantic Web applications. (c) 2008 Elsevier B. V. All rights reserved.
We describe implementation of a modular system of computer codes for inversion of electromagnetic geophysical data, referred to as ModEM. The system is constructed with a fine level of modular granularity, with basic ...
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We describe implementation of a modular system of computer codes for inversion of electromagnetic geophysical data, referred to as ModEM. The system is constructed with a fine level of modular granularity, with basic components of the inversion - forward modeling, sensitivity computations, inversion search algorithms, model parametrization and regularization, data functionals - interchangeable, reusable and readily extensible. Modular sensitivity computations and generic interfaces to parallelized inversion algorithms provide a ready framework for rapid implementation of new applications or inversion algorithms. We illustrate the code's versatility and capabilities for code reuse through implementation of 3D magnetotelluric (MT) and controlled-source EM (CSEM) inversions, using essentially the same components. (C) 2014 Elsevier Ltd. All rights reserved.
The aim of this paper is to describe an efficient method to connect two independent softwares so as to jointly use best qualities of each software around a complex problem solved by the finite element emethod (FEM). T...
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The aim of this paper is to describe an efficient method to connect two independent softwares so as to jointly use best qualities of each software around a complex problem solved by the finite element emethod (FEM). This connection makes it possible to extend quickly and easily the applicability of new models developed in academic softwares, by their simultaneous use with commercial softwares. This is particularly interesting when these models are vey difficult to implement directly in commercial softwares. Most of the commercial FEM applications allow users to add additional features, physical models or boundary conditions via a programing interface. Within these user routines, access to internal data structures is possible, either through subroutine parameters and global variables, or via internal modules for reading and storing data. We use these capabilities to link the commercial software ABAQUS and an academic object-oriented C++ software HEREZH++, via the user-defined mechanical material behaviour (Umat). In this interface, HEREZH++ computes the mechanical behaviour of material and the code coupling performs a communication procedure between ABAQUS and HEREZH++. This paper describes this architecture which allows to implement easily original behaviour law and an interface written in c/C++. Several test samples are presented to show the efficiency and accuracy of the proposed implementations concernning the computational time. In particular, an industrial test is carried out with an original behaviour model of clasto-viscohysteresis which would have been very difficult to implement directly in ABAQUS. (c) 2008 Elsevier Ltd. All rights reserved.
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