65 research outputs found
Psychophysical or spinal reflex measures when assessing conditioned pain modulation?
Background:
Assessing conditioning pain modulation (CPM) with spinal reflex measures may produce more objective and stable CPM effects than using psychophysical measures. The aim of the study was to compare the CPM effect and testâretest reliability between a psychophysical protocol with thermal testâstimulus and a spinal reflex protocol with electrical testâstimulus.
Methods:
Twentyâfive healthy volunteers participated in two identical experiments separated by minimum 1 week. The thermal testâstimulus was a constant heat stimulation of 120 s on the subjectsâ forearm with continuous ratings of pain intensity on a 10 cm visual analogue scale. The electrical testâstimulus was repeated electrical stimulation on the arch of the foot for 120 s, which elicited a nociceptive withdrawal reflex recorded from the anterior tibial muscle. Conditioning stimulus was a 7°C water bath. Differences in the magnitude and testâretest reliability were investigated with repeatedâmeasures analysis of variance and by relative and absolute reliability indices.
Results:
The CPM effect was â46% and 4.5% during the thermal and electrical testâstimulus (p < 0.001) respectively. Intraclass correlation coefficient of 0.5 and 0.4 was found with the electrical and thermal testâstimulus respectively. Wide limits of agreement were found for both the electrical (â3.4 to 3.8 mA) and the thermal testâstimulus (â3.2 to 3.6 cm).
Conclusions:
More pronounced CPM effect was demonstrated when using a psychophysical protocol with thermal testâstimulus compared to a spinal reflex protocol with electrical testâstimulus. Fair relative reliability and poor absolute reliability (due to high intraindividual variability) was found in both protocols.
Significance:
The large difference in CPM effect between the two protocols suggests that the CPM effect relates to pain perception rather than nociception on the spinal level. Due to poor absolute intrarater reliability, we recommend caution and further research before using any of the investigated CPM protocols in clinical decision making on an individual level
Non-functional properties in the model-driven development of service-oriented systems
Systems based on the service-oriented architecture (SOA) principles have become an important cornerstone of the development of enterprise-scale software applications. They are characterized by separating functions into distinct software units, called services, which can be published, requested and dynamically combined in the production of business applications. Service-oriented systems (SOSs) promise high flexibility, improved maintainability, and simple re-use of functionality. Achieving these properties requires an understanding not only of the individual artifacts of the system but also their integration. In this context, non-functional aspects play an important role and should be analyzed and modeled as early as possible in the development cycle. In this paper, we discuss modeling of non-functional aspects of service-oriented systems, and the use of these models for analysis and deployment. Our contribution in this paper is threefold. First, we show how services and service compositions may be modeled in UML by using a profile for SOA (UML4SOA) and how non-functional properties of service-oriented systems can be represented using the non-functional extension of UML4SOA (UML4SOA-NFP) and the MARTE profile. This enables modeling of performance, security and reliable messaging. Second, we discuss formal analysis of models which respect this design, in particular we consider performance estimates and reliability analysis using the stochastically timed process algebra PEPA as the underlying analytical engine. Last but not least, our models are the source for the application of deployment mechanisms which comprise model-to-model and model-to-text transformations implemented in the framework VIATRA. All techniques presented in this work are illustrated by a running example from an eUniversity case study
Distributed Control for a Task-Level Programmable Multi-Arm Robotic Assembly Cell
NRC publication: Ye
Absolute Position Measurement Using Pseudo-Random Binary Encoding
Abstract: This paper presents a new absolute position measurement method using pseudo-random binary sequences. This encoding technique has the notable advantage of requiring only one code-symbol per quantization interval. This compact encoding method offers an economical solution to very-highresolution absolute position applications: shaft encoders, linear encoders, and "automated guided vehicle" (AGV) navigation
- âŠ