A conceptual framework for requirements engineering

A framework for assessing research and practice in requirements engineering is proposed. The framework is used to survey state of the art research contributions and practice. The framework considers a task activity view of requirements, and elaborates different views of requirements engineering (RE) depending on the starting point of a system development. Another perspective is to analyse RE from different conceptions of products and their properties. RE research is examined within this framework and then placed in the context of how it extends current system development methods and systems analysis techniques.     

A mathematical framework for active steganalysis

A mathematical framework for steganalysis is presented in this Paper, with linear steganography being the main focus. A mathematically formal definition of steganalysis is given. Then active steganalysis, defined as the extraction of a hidden message with little or no a priori information, is formulated as a blind system identification problem within this framework. Conditions for identifiability (i.e., successful steganalysis) are derived. A procedure to systematically exploit any available spatial and temporal diversity information for efficient steganalysis is also discussed. Experimental results are given for steganalysis of Gaussian distributed, spread spectrum image steganography and watermarking. The proposed technique is observed to produce impressive results for a variety of performance measures. Based on the results we conclude that a common belief, namely, spread spectrum steganography/watermarking, is secure because the low strength, noise-like message carrier is no longer valid within the current context. Therefore, new questions regarding steganography security that differ from the standard information theoretic notion are raised and some answers are provided.     

A conceptual framework for society-oriented decision support

Inspired by the operation of human social organisation, this paper presents a new architecture—a pyramid-committee—for developing society-oriented intelligence, whose structure imitates the organisation of human society in its decision making. The system takes a pyramid-like hierarchical structure with links in the pyramid forming a semi-lattice, which relate not only to nodes in the same layer, but also to others in different layers. The output of the system is a result of the negotiation and balancing of different interests. For such a system to function, the main difficulties concern the complicated relationships between different factors or agents. Focussing on the airport environment audit, we discuss the development of a model framework and the role of neural networks.     

A methodological framework for viewpoint-oriented conceptual modeling

To solve any nontrivial problem, it first needs to be conceptualized, taking into account the individual who has the problem. However, a problem is generally associated with more than one individual, as is usually the case in software development. Therefore, this process has to take into account different viewpoints about the problem and any discrepancies that could arise as a result. Traditionally, conceptualization in software engineering has omitted the different viewpoints that the individuals may have of the problem and has inherently enforced consistency in the event of any discrepancies, which are considered as something to be systematically rejected. The paper presents a methodological framework that explicitly drives the conceptualization of different viewpoints and manages the different types of discrepancies that arise between them, which become really important in the process. The definition of this framework is generic, and it is therefore independent of any particular software development paradigm. Its application to software engineering means that viewpoints and their possible discrepancies can be considered in the software process conceptual modeling phase. This application is illustrated by means of what is considered to be a standard problem: the IFIP case.     

A conceptual modeling quality framework

The goal of any modeling activity is a complete and accurate understanding of the real-world domain, within the bounds of the problem at hand and keeping in mind the goals of the stakeholders involved. High-quality representations are critical to that understanding. This paper proposes a comprehensive Conceptual Modeling Quality Framework, bringing together two well-known quality frameworks: the framework of Lindland, Sindre, and S?lvberg (LSS) and that of Wand and Weber based on Bunge’s ontology (BWW). This framework builds upon the strengths of the LSS and BWW frameworks, bringing together and organizing the various quality cornerstones and then defining the many quality dimensions that connect one to another. It presents a unified view of conceptual modeling quality that can benefit both researchers and practitioners.     

A low-latency computing framework for time-evolving graphs

The Journal of Supercomputing - The demand to deliver fast responses in processing time-evolving graphs is higher than ever before in a large number of big data applications. This problem promotes...     

Compiling conceptual graphs

The paper addresses problems in conceptual graph implementation: subsumption and classification in a taxonomy. Conceptual graphs are typically stored using a directed acyclic graph data structure based on the partial order over conceptual graphs. We give an improved algorithm for classifying conceptual graphs into this hierarchy. It prunes the search space in the database using the information gathered while searching. We show how conceptual graphs in this hierarchy can be compiled into instructions which represent specialized cases of the canonical formation rules. This compiles subsumption of conceptual graphs and compresses knowledge in a knowledge base. Conceptual graphs are compiled as differences between adjacent graphs in the hierarchy. The differences represent the rules used in deriving the graph from the adjacent graphs. We illustrate how the method compresses knowledge bases in some experiments. Compilation is effected in three ways: removal of redundant data, use of simple instructions which ignore redundant checks when performing matching, and by sharing common processing between graphs     

A framework for reviewing domain specific conceptual models

Conceptual models are used in understanding and communicating the domain of interest during analysis phase of system development. As they are used in early phases, errors and omissions may propagate to later phases and may be very costly to correct. This paper proposes a framework for evaluating conceptual models when represented in a domain specific language based on UML constructs. The framework describes the main aspects to be considered when conceptual models are represented in a domain specific language, presents a classification of semantic issues and some evaluation indicators. The indicators can, in principle, identify situations in the models where inconsistencies or incompleteness might occur. Whether these are real concerns might depend on domain semantics, hence these are semantic, not syntactic checks. The use of the proposed review framework is illustrated in the context of two conceptual models in a domain specific notation, KAMA. With reviews based on the framework, it is possible to spot semantic issues which are not noticed by case tools and help the analyst to identify more information about the domain.     

A reverse logistics decisions conceptual framework

This research work proposes a reverse logistics decisions conceptual framework that offers flexibility and covers a wide variety of situations that may arise in the practical working environment. The methodology adopted in this paper is inspired by and taken from the various research papers published in the literature. The proposed framework considers seven important elements of the reverse logistics system. It is divided into three hierarchical levels (strategic, tactical, and operational). By carrying out experimentation with the proposed conceptual model, all three levels were tested in different industrial sectors during its development. Three real-world case studies are presented to test and to show the flexibility and applicability of the framework. The proposed conceptual framework will help practitioners in the field to structure their reverse logistics activities and also help academics in developing better decision models.     

A framework for empirical evaluation of conceptual modeling techniques

The paper presents a framework for the empirical evaluation of conceptual modeling techniques used in requirements engineering. The framework is based on the notion that modeling techniques should be compared via their underlying grammars. The framework identifies two types of dimensions in empirical comparisons—affecting and affected dimensions. The affecting dimensions provide guidance for task definition, independent variables and controls, while the affected dimensions define the possible mediating variables and dependent variables. In particular, the framework addresses the dependence between the modeling task—model creation and model interpretation—and the performance measures of the modeling grammar. The utility of the framework is demonstrated by using it to categorize existing work on evaluating modeling techniques. The paper also discusses theoretical foundations that can guide hypothesis generation and measurement of variables. Finally, the paper addresses possible levels for categorical variables and ways to measure interval variables, especially the grammar performance measures.     

Line-drawing interpretation: A mathematical framework

We report progress toward a mathematical theory of line-drawing interpretation. A working framework is developed, and a variety of tools and techniques are demonstrated within it. We begin with a concise review of related work. Then, we detail our assumptions—the imaging geometry is well approximated by orthographic or perspective projection, the viewpoint is general, the world is composed of piecewise C³ surfaces, and continuous-surface-normal depth discontinuities are the only viewpoint-dependent edges. This is followed by the presentation of a projective mapping which we expect will find considerable use in the extension of results derived for orthographic projection to perspective projection. Next, Whitney's definition of an excellent mapping is reviewed and it is shown that both orthographic and perspective projections of piecewise C³ surfaces are excellent under general viewpoint. It is thus demonstrated that there are basically only two different types of local singularities—folds and cusps—associated with the projection of a C³ surface. The loci of the singular values are C³ curves in the line drawing, except for cusps at their nonjunction terminations. All previous work based on Whitney's results on excellent mappings has needed to assume stability under perturbation of the viewed surface. This assumption, which is unverifiable by a remote observer, is rendered unnecessary by our results. After characterizing viewpoint-dependent edges as folds and cusps, we turn our attention to the modes of interaction between viewpoint-independent and viewpoint-dependent edges. It is shown that only isolated points on viewpoint-dependent edges may lie on surface-patch boundaries, and that viewpoint-independent and viewpoint-dependent edges are always cotangent at their nonocclusion junctions in line drawings, but have different curvatures. Finally, we investigate continuity constraints imposed on the scene by its line drawing. We show that a viewpoint-independent edge in a line drawing is C³ if and only if the edge is C³ in space, and that a viewpoint-dependent edge in a line drawing is C³ if and only if the surface on which it lies in space is C³ along the edge.This work was supported in part by the Defense Advanced Research Projects Agency under Contract N00039-84-C-0211.     

A conceptual framework for trajectory-based medical analytics with IoT contexts

With the increasing availability of medical IoT devices, it becomes feasible to collect health contexts from personal IoT devices and perform analytics to assess the health conditions and identify potential diseases. However, there exist technical challenges in developing such personal healthcare applications; transforming disease diagnosis methods of physicians in machine-readable forms and software implementation of the medical analytic schemes. In this paper, we present a methodology foundation for analyzing medical contexts. That is, we formalize five representative medical diagnosis schemes for personal healthcare application.     

A knowledge-based framework for creative conceptual design of multi-disciplinary systems

Designers often have difficulty in fulfilling creative conceptual designs of multi-disciplinary systems due to the lack of sufficient multi-disciplinary knowledge. Therefore, this paper proposes a knowledge-based framework for the creative conceptual design of multi-disciplinary systems through reusing and synthesizing known principle solutions in various disciplines together. It comprises a formal constraints-based approach for representing the desired functions, a domain-independent approach for modeling functional knowledge of known principle solutions, and a heterogeneous-object-state-search-based approach for synthesizing known principle solutions together for achieving the desired functions. A design case illustrates that the proposed framework can successfully achieve creative conceptual design of multi-disciplinary systems. A prototype system, called the Intelligent Creative Conceptual Design Platform, is implemented based on this framework.     

A formal mathematical framework for modeling probabilistic hybrid systems

The development of autonomous agents, such as mobile robots and software agents, has generated considerable research in recent years. Robotic systems, which are usually built from a mixture of continuous (analog) and discrete (digital) components, are often referred to as hybrid dynamical systems. Traditional approaches to real-time hybrid systems usually define behaviors purely in terms of determinism or sometimes non-determinism. However, this is insufficient as real-time dynamical systems very often exhibit uncertain behavior. To address this issue, we develop a semantic model, Probabilistic Constraint Nets (PCN), for probabilistic hybrid systems. PCN captures the most general structure of dynamic systems, allowing systems with discrete and continuous time/variables, synchronous as well as asynchronous event structures and uncertain dynamics to be modeled in a unitary framework. Based on a formal mathematical paradigm exploiting abstract algebra, topology and measure theory, PCN provides a rigorous formal programming semantics for the design of hybrid real-time embedded systems exhibiting uncertainty.      

面向虚拟采办的智能决策支持系统概念框架

提出一种面向虚拟采办全寿命周期、全系统、全方位决策的智能决策支持系统SBA—IDSS概念框架．作为真实世界采办最终需求的抽象描述,它属于与实现无关的规范性模型体系,由它定义应用领域、用户概念和环境特征．同时它是数字世界中拟实现的初始工程模型,包括与实现无关的设计可行性模型、规划模型及功能顶层分解．该框架支持系统的自组织、自适应智能行为,预期可按需组成模型与仿真、文件、知识、通信及数据驱动的各类实用决策支持系统．该框架通过一项SBA实例的验证,得到可用性的正面评价．     

A content-search information retrieval process based on conceptual graphs

An intelligent information retrieval system is presented in this paper. In our approach, which complies with the logical view of information retrieval, queries, document contents and other knowledge are represented by expressions in a knowledge representation language based on the conceptual graphs introduced by Sowa. In order to take the intrinsic vagueness of information retrieval into account, i.e. to search documents imprecisely and incompletely represented in order to answer a vague query, different kinds of probabilistic logic are often used. The search process described in this paper uses graph transformations instead of probabilistic notions. This paper is focused on the content-based retrieval process, and the cognitive facet of information retrieval is not directly addressed. However, our approach, involving the use of a knowledge representation language for representing data and a search process based on a combinatorial implementation of van Rijsbergen’s logical uncertainty principle, also allows the representation of retrieval situations. Hence, we believe that it could be implemented at the core of an operational information retrieval system. Two applications, one dealing with academic libraries and the other concerning audiovisual documents, are briefly presented.     

Distributed environment: A conceptual framework using objects

We present a conceptual framework for a distributed office system using concepts inherent to object-oriented formalism. The functions of the active object and the procedure servers are described. So are the attributes of the objects stored in these two servers. In order to endow the individual workstations with as much autonomy as possible, we develop a coarse-grained algorithm for active and procedural object distribution. An office model should have a high level of evolvability. To accommodate this phenomenon we devise a mechanism to enable the model to transit one state to another with a minimum level of perturbation.