Multi-level constraints

Meta-modelling and domain-specific modelling languages are supported by multi-level modelling which liberates model-based engineering from the traditional two-level type-instance language architecture. Proponents of this approach claim that multi-level modelling increases the quality of the resulting systems by introducing a second abstraction dimension and thereby allowing both intra-level abstraction via sub-typing and inter-level abstraction via meta-types. Modelling approaches include constraint languages that are used to express model semantics. Traditional languages, such as OCL, support intra-level constraints, but not inter-level constraints. This paper motivates the need for multi-level constraints, shows how to implement such a language in a reflexive language architecture and applies multi-level constraints to an example multi-level model

Multi-level modeling with LML : A contribution to the Multi-level Process Challenge

This paper presents a solution to the MULTI Process Challenge which was first posed to the participants of the MULTI workshop at the MODELS conference in 2019 and subsequently adapted for this special issue of the EMISA Journal. The structure of the paper therefore follows the guidelines laid out in the Challenge description. The models are represented in the Level-agnostic Modeling Language LML and the DOCL constraint language using the Melanee deep modeling tool. After first outlining the case study and documenting which aspects are supported in the LML solution, the paper presents multi-level models for both the insurance and the software engineering domains. This is followed by a discussion of the strengths and weaknesses of the approach. The presented model covers all mandatory and optional aspects of the Challenge case study

The Relevance of Executive Functions in Academic Production in Middle School

The present study investigated the role that executive function plays on academic production in middle school from a prototype perspective. It was hypothesized that middle school teachers\u27 prototypical ratings of the executive function capacities of middle school students who are academically successful would differ significantly from these same middle school teachers\u27 prototypical ratings of the executive function capacities of middle school students who are academically unsuccessful. The study used archival data consisting of items from the Behavior Rating Inventory of Executive Function (BRIEF), a questionnaire that was completed by middle school teachers during a professional in-service workshop at four large urban middle schools. The concept of academic competence was viewed as a category, structured by the similarities of successful middle school students to one another in discrete behavioral manifestations of executive functions and organized around a prototype that represents the central tendency of all the exemplars in the category of successful students, as operationally defined by the BRIEF items. A second prototype was structured in a similar manner for the unsuccessful student category. To examine differences between these two prototypical categories, t tests were conducted using T scores from the eight BRIEF domains. It was postulated that there would be a significant difference between the successful learner prototype and the unsuccessful learner prototype. It was expected that the successful student prototype would possess fewer executive function impairments than the unsuccessful student prototype. Statistically significant findings were obtained, suggesting that teachers\u27 perceptions of prototypical successful students differed from these same teachers\u27 perceptions of prototypical unsuccessful students in their behavioral manifestations of executive function capacities in all eight domains of the BRIEF. Teachers\u27 ratings most consistently produced the expected pattern of T score results for the Inhibit, Initiate, Plan/Organize, Monitor, and Working Memory scales. Teachers were least likely to see large differences between successful and unsuccessful students in behaviors that reflected the executive function capacities of Shift, Emotional Control, and Organization of Materials. The results of the study supported the hypothesis that successful students exhibit very few executive function difficulties, while unsuccessful students exhibit executive function difficulties in the clinically significant range. The present study investigated the role that executive function plays on academic production in middle school from a prototype perspective. It was hypothesized that middle school teachers\u27 prototypical ratings of the executive function capacities of middle school students who are academically successful would differ significantly from these same middle school teachers\u27 prototypical ratings of the executive function capacities of middle school students who are academically unsuccessful. The study used archival data consisting of items from the Behavior Rating Inventory of Executive Function (BRIEF), a questionnaire that was completed by middle school teachers during a professional in-service workshop at four large urban middle schools. The concept of academic competence was viewed as a category, structured by the similarities of successful middle school students to one another in discrete behavioral manifestations of executive functions and organized around a prototype that represents the central tendency of all the exemplars in the category of successful students, as operationally defined by the BRIEF items. A second prototype was structured in a similar manner for the unsuccessful student category. To examine differences between these two prototypical categories, t tests were conducted using T scores from the eight BRIEF domains. It was postulated that there would be a significant difference between the successful learner prototype and the unsuccessful learner prototype. It was expected that the successful student prototype would possess fewer executive function impairments than the unsuccessful student prototype. Statistically significant findings were obtained, suggesting that teachers\u27 perceptions of prototypical successful students differed from these same teachers\u27 perceptions of prototypical unsuccessful students in their behavioral manifestations of executive function capacities in all eight domains of the BRIEF. Teachers\u27 ratings most consistently produced the expected pattern of T score results for the Inhibit, Initiate, Plan/Organize, Monitor, and Working Memory scales. Teachers were least likely to see large differences between successful and unsuccessful students in behaviors that reflected the executive function capacities of Shift, Emotional Control, and Organization of Materials. The results of the study supported the hypothesis that successful students exhibit very few executive function difficulties, while unsuccessful students exhibit executive function difficulties in the clinically significant range

Ecology, Problem Framing and Local Land Use Controls: A Case Study of Socio-Ecological Governance in Franklin County, Idaho

Due to the continuity of energy and material flows, the persistence of an ecological network necessarily includes a linking of ecological units from local and immediate to regional and broad-ranging scales. Humans are an integral part of ecosystems acting as resource consumers and agents of change, and all systems can be considered combined \u27socio-ecological\u27 systems. Where environmental and social systems lack coordination, mismatches between the temporal, spatial or functional scales at which these systems operate lead to resource use inefficiencies and the loss of ecosystem components and functioning. This case study of Franklin County, Idaho documents a recent land use ordinance revision process to offer a critical evaluation of local institutional actions in the face of change. The case study serves to identify scale mismatches between institutional (social) and ecological facets of county governance and to develop potential solutions for those discrepancies. Because no clear framing of complex land use issues served to coordinate a regulatory strategy for the County, the Comprehensive Plan and Land Development Code remained organized around individual land use issues rather than recognizing multi-scale linkages and limited the potential for cross-scale, cohesive governance of that social-ecological system. Two main influences emerged- the institutional framework and the nature of information used to make decisions. These were significant in contributing to scale mismatch because they shaped institutional problem framing which subsequently set policy outcomes. Despite such institutional limitations and limited problem framing, the findings of this case study imply that the Franklin County government possesses a basic organizational and communicative potential that could be harnessed to improve flexibility and synchronization in the regional governance of linked socioecological processes

Optimization of Operation Sequencing in CAPP Using Hybrid Genetic Algorithm and Simulated Annealing Approach

In any CAPP system, one of the most important process planning functions is selection of the operations and corresponding machines in order to generate the optimal operation sequence. In this paper, the hybrid GA-SA algorithm is used to solve this combinatorial optimization NP (Non-deterministic Polynomial) problem. The network representation is adopted to describe operation and sequencing flexibility in process planning and the mathematical model for process planning is described with the objective of minimizing the production time. Experimental results show effectiveness of the hybrid algorithm that, in comparison with the GA and SA standalone algorithms, gives optimal operation sequence with lesser computational time and lesser number of iterations

Optimization of Operation Sequencing in CAPP Using Hybrid Genetic Algorithm and Simulated Annealing Approach

In any CAPP system, one of the most important process planning functions is selection of the operations and corresponding machines in order to generate the optimal operation sequence. In this paper, the hybrid GA-SA algorithm is used to solve this combinatorial optimization NP (Non-deterministic Polynomial) problem. The network representation is adopted to describe operation and sequencing flexibility in process planning and the mathematical model for process planning is described with the objective of minimizing the production time. Experimental results show effectiveness of the hybrid algorithm that, in comparison with the GA and SA standalone algorithms, gives optimal operation sequence with lesser computational time and lesser number of iterations

Autonomous Navigation of Automated Guided Vehicle Using Monocular Camera

This paper presents a hybrid control algorithm for Automated Guided Vehicle (AGV) consisting of two independent control loops: Position Based Control (PBC) for global navigation within manufacturing environment and Image Based Visual Servoing (IBVS) for fine motions needed for accurate steering towards loading/unloading point. The proposed hybrid control separates the initial transportation task into global navigation towards the goal point, and fine motion from the goal point to the loading/unloading point. In this manner, the need for artificial landmarks or accurate map of the environment is bypassed. Initial experimental results show the usefulness of the proposed approach.COBISS.SR-ID 27383808

Autonomous Navigation of Automated Guided Vehicle Using Monocular Camera

This paper presents a hybrid control algorithm for Automated Guided Vehicle (AGV) consisting of two independent control loops: Position Based Control (PBC) for global navigation within manufacturing environment and Image Based Visual Servoing (IBVS) for fine motions needed for accurate steering towards loading/unloading point. The proposed hybrid control separates the initial transportation task into global navigation towards the goal point, and fine motion from the goal point to the loading/unloading point. In this manner, the need for artificial landmarks or accurate map of the environment is bypassed. Initial experimental results show the usefulness of the proposed approach.COBISS.SR-ID 27383808

Studies related to the process of program development

The submitted work consists of a collection of publications arising from research carried out at Rhodes University (1970-1980) and at Heriot-Watt University (1980-1992). The theme of this research is the process of program development, i.e. the process of creating a computer program to solve some particular problem. The papers presented cover a number of different topics which relate to this process, viz. (a) Programming methodology programming. (b) Properties of programming languages. aspects of structured. (c) Formal specification of programming languages. (d) Compiler techniques. (e) Declarative programming languages. (f) Program development aids. (g) Automatic program generation. (h) Databases. (i) Algorithms and applications