966,227 research outputs found
Multi-objective Optimal Kinematic Design of 3-TPS/TP Parallel Robot
Abstract. The purpose of this research work is to find the optimized kinematic structural parameters of the 3-TPS/TP parallel manipulator while taking into consideration the workspace, kinematic properties and other factors. The Ranked Pareto Particle Swarm Optimization (RP-PSO) approach is applied to solve the multi-objective optimization problems. Firstly, the structure of the parallel manipulator and its kinematic model are devised. Then, we set up the kinematical performance indices for the evaluation of manipulator working properties, including Local Condition Index (LCI), Global Condition Index (GCI) and Good Condition Workspace (GCW). The optimization is further carried out in a Parameter Design Space (PDS) with normalized geometry parameters. Then the geometry optimization problems are solved using a PDS based RP-PSO approach. Finally, the feasibility of this approach is supported by examples given this paper
Describing Scholarly Works with Dublin Core: A Functional Approach
This article describes the development of the Scholarly Works Application Profile (SWAP)—a Dublin Core application profile for describing scholarly texts. This work provides an active illustration of the Dublin Core Metadata Initiative (DCMI) “Singapore Framework” for Application Profiles, presented at the DCMI Conference in 2007, by incorporating the various elements of Application Profile building as defined by this framework—functional requirements, domain model, description set profile, usage guidelines, and data format. These elements build on the foundations laid down by the Dublin Core Abstract Model and utilize a preexisting domain model (FR-BR—Functional Requirements for Bibliographic Records) in order to support the representation of complex data describing multiple entities and their relationships. The challenges of engaging community acceptance and implementation will be covered, along with other related initiatives to support the growing corpus of scholarly resource types, such as data objects, geographic data, multimedia, and images whose structure and metadata requirements introduce the need for new application profiles. Finally, looking to other initiatives, the article will comment on how Dublin Core relates to the broader scholarly information world, where projects like Object Re-use and Exchange are attempting to better equip repositories to exchange resources
Transforming ASN.1 Specifications into CafeOBJ to assist with Property Checking
The adoption of algebraic specification/formal method techniques by the
networks' research community is happening slowly but steadily. We work towards
a software environment that can translate a protocol's specification, from
Abstract Syntax Notation One (ASN.1 - a very popular specification language
with many applications), into the powerful algebraic specification language
CafeOBJ. The resulting code can be used to check, validate and falsify critical
properties of systems, at the pre-coding stage of development. In this paper,
we introduce some key elements of ASN.1 and CafeOBJ and sketch some first steps
towards the implementation of such a tool including a case study.Comment: 8 pages, 12 figure
Recommended from our members
Learning-based constraints on schemata
Schemata are frequently used in cognitive science as a descriptive framework for explaining the units of knowledge. However, the specific properties which comprise a schema are not consistent across authors. In this paper we attempt to ground the concept of a schema based on constraints arising from issues of learning. To do this, we consider the different forms of schemata used in computational models of learning. We propose a framework for comparing forms of schemata which is based on the underlying representation used by each model, and the mechanisms used for learning and retrieving information from its memory. Based on these three characteristics, we compare examples from three classes of model, identified by their underlying representations, specifically: neural network, production-rule and symbolic network models
Engineering design in a different way: cognitive perspective on the contact and channel model approach
Engineering design often involves the integration of new design ideas into existing products, requiring designers to think simultaneously about abstract properties and functions as well as concrete solution constraints. Often designers struggle to reason with functional descriptions, while not fixating on existing solutions. This paper introduces the Contact & Channel Model (C&CM) approach, which combines abstract functional models of technical systems with the concrete geometric descriptions that many designers are familiar with. By locating functions at working surface pairs, they receive a concrete location in mental models. The C&CM approach can be applied to analyze existing product descriptions and synthesize creative new solutions for parts of the system or for entire new systems. At the moment the approach is being developed into an complete modeling and problem solving approach. C&CM has been used for several years in undergraduate engineering teaching at the University of Karlsruhe (TH) and is increasingly being introduced into industry by its use in research and development projects, by its students and its alumni
On the construction of hierarchic models
One of the main problems in the field of model-based diagnosis of technical systems today is finding the most useful model or models of the system being diagnosed. Often, a model showing the physical components and the connections between them is all that is available. As systems grow larger and larger, the run-time performance of diagnostic algorithms decreases considerably when using these detailed models. A solution to this problem is using a hierarchic model. This allows us to first diagnose the system using an abstract model, and then use this solution to guide the diagnostic process using a more detailed model. The main problem with this approach is acquiring the hierarchic model. We give a generic hierarchic diagnostic algorithm and show how the use of certain classes of hierarchic models can increase the performance of this algorithm. We then present linear time algorithms for the automatic construction of these hierarchic models, using the detailed model and extra information about cost of probing points and invertibility of components
- …