Search results for "GRASP"
showing 10 items of 84 documents
Heuristics and meta-heuristics for 2-layer straight line crossing minimization
2003
AbstractThis paper presents extensive computational experiments to compare 12 heuristics and 2 meta-heuristics for the problem of minimizing straight-line crossings in a 2-layer graph. These experiments show that the performance of the heuristics (largely based on simple ordering rules) drastically deteriorates as the graphs become sparser. A tabu search metaheuristic yields the best results for relatively dense graphs, with a GRASP implementation as close second. Furthermore, the GRASP approach outperforms all other approaches when tackling low-density graphs.
The Psychology of Thinking in Creating AI
2021
The broad-scale emergence of AI in industry calls forth basic questions in terms of the knowledge bases and approaches relevant for its design. Engineering design has been mainly developed for electromechanical artifacts. In practice, this has meant that the scientific knowledge required for creating technical artifacts such as engines, cars, ships, cranes, telephones, radios, TVs, and simple data processing units has been natural science. However, one cannot find intelligent processes by means of physics and chemistry. Natural scientific phenomena follow their deterministic laws, but intelligence is based on selection and decision processes. The conceptual landscape of natural science is o…
Seeking for the Grasp : An Iterative Subdivision Model of Conceptualisation
2019
Concepts are fundamental collective constructs of individual items that are capable of abstracting meaningfully homogeneous groupings of phenomena. This capability is a prerequisite for communication and action and gives structure to learning and memory. Our study is aligned with the vast paradigm that assumes embodied cognition, rooted in Merleau-Ponty (Phenomenology of perception (trans: C. Smith). Routledge and Kegan Paul, London, 1962), seminally articulated by Varela et al. (Embodied mind: cognitive science and human experience. MIT Press, Cambridge, MA, 1991) and existing today in a number of variants that have been reviewed by Wilson (Six views of embodied cognition. Springer. Psycho…
A Taxonomy for App-Enabled Devices: Mastering the Mobile Device Jungle
2018
While the term application is known for a long time, what we now refer to as mobile apps has facilitated task-oriented, interoperable software. The term was initially only used for smartphones and tablets, but desktop software now is also referred to as apps. More important than the wording, however, is the trend towards app-enablement of many further kinds of devices such as smart TVs and wearables. App-enabled devices usually share some characteristics and developing apps is often similar. However, many complexities must be mastered: Device fragmentation and cross-platform app development already are challenging when only considering smartphones. When trying to grasp the field as a whole,…
Tactile input of the hand and the control of reaching to grasp movements
1997
The role of tactile information of the hand in the control of reaching to grasp movements was investigated. The kinematics of both reaching (or transport) and grasp components were studied in healthy subjects in two experimental conditions. In one condition (control condition) subjects were required to reach and grasp an object that could have two sizes and that could be located at two distances from the viewer. In the other condition (anaesthesia condition) the same movements were executed, but anaesthesia was provided to the subjects' fingertips. In both conditions vision of the hand was prevented during movement. Anaesthesia affected mainly the kinematics of the first phase of grasping, …
M-GRASP: A GRASP With Memory for Latency-Aware Partitioning Methods in DVE Systems
2009
A necessary condition for providing quality of service to distributed virtual environments (DVEs) is to provide a system response below a maximum threshold to the client computers. In this sense, latency-aware partitioning methods try to provide response times below the threshold to the maximum number of client computers as possible. These partitioning methods should find an assignment of clients to servers that optimizes system throughput, system latency, and partitioning efficiency. In this paper, we present a new algorithm based on greedy randomized adaptive search procedure with memory for finding the best solutions as possible to this problem. We take into account several different alt…
Classification based on Iterative Object Symmetry Transform
2004
The paper shows an application of a new operator named the iterated object transform (IOT) for cell classification. The IOT has the ability to grasp the internal structure of a digital object and this feature can be usefully applied to discriminate structured images. This is the case of cells representing chondrocytes in bone tissue, giarda protozoan, and myeloid leukaemia. A tree classifier allows us to discriminate the three classes with a good accuracy.
Iterative Symmetry Detection: Shrinking vs. Decimating Patterns
2005
This paper introduces a new mechanism that consists of applying a symmetry operator on an iteratively transformed version of the input image. The nature of the transformation characterizes the operator. Here, we consider the Object Symmetry Transform combined with the morphological operator erosion and the pyramid decimation respectively. The derived operators have been applied on both binary and gray levels images, comparing their ability to grasp the internal structure of a digital object. We present some experiments to evaluate their performances and check them for result quality versus computing complexity.
Branch and bound for the cutwidth minimization problem
2013
The cutwidth minimization problem consists of finding a linear arrangement of the vertices of a graph where the maximum number of cuts between the edges of the graph and a line separating consecutive vertices is minimized. We first review previous approaches for special classes of graphs, followed by lower bounds and then a linear integer formulation for the general problem. We then propose a branch-and-bound algorithm based on different lower bounds on the cutwidth of partial solutions. Additionally, we introduce a Greedy Randomized Adaptive Search Procedure (GRASP) heuristic to obtain good initial solutions. The combination of the branch-and-bound and GRASP methods results in optimal solu…
A computational study of LP-based heuristic algorithms for two-dimensional guillotine cutting stock problems
2002
In this paper we develop and compare several heuristic methods for solving the general two-dimensional cutting stock problem. We follow the Gilmore-Gomory column generation scheme in which at each iteration a new cutting pattern is obtained as the solution of a subproblem on one stock sheet. For solving this subproblem, in addition to classical dynamic programming, we have developed three heuristic procedures of increasing complexity, based on GRASP and Tabu Search techniques, producing solutions differing in quality and in time requirements. In order to obtain integer solutions from the fractional solutions of the Gilmore-Gomory process, we compare three rounding procedures, rounding up, t…