Topic
Duty cycle
About: Duty cycle is a research topic. Over the lifetime, 29008 publications have been published within this topic receiving 299389 citations. The topic is also known as: duty factor & on time.
Papers published on a yearly basis
Papers
More filters
05 Nov 2003
TL;DR: T-MAC, a contention-based Medium Access Control protocol for wireless sensor networks, introduces an adaptive duty cycle in a novel way: by dynamically ending the active part of it to handle load variations in time and location.
Abstract: In this paper we describe T-MAC, a contention-based Medium Access Control protocol for wireless sensor networks. Applications for these networks have some characteristics (low message rate, insensitivity to latency) that can be exploited to reduce energy consumption by introducing an activesleep duty cycle. To handle load variations in time and location T-MAC introduces an adaptive duty cycle in a novel way: by dynamically ending the active part of it. This reduces the amount of energy wasted on idle listening, in which nodes wait for potentially incoming messages, while still maintaining a reasonable throughput.We discuss the design of T-MAC, and provide a head-to-head comparison with classic CSMA (no duty cycle) and S-MAC (fixed duty cycle) through extensive simulations. Under homogeneous load, T-MAC and S-MAC achieve similar reductions in energy consumption (up to 98%) compared to CSMA. In a sample scenario with variable load, however, T-MAC outperforms S-MAC by a factor of 5. Preliminary energy-consumption measurements provide insight into the internal workings of the T-MAC protocol.
2,844 citations
TL;DR: The goal of this paper is not to suggest that the conversion of vibrations is the best or most versatile method to scavenge ambient power, but to study its potential as a viable power source for applications where vibrations are present.
2,727 citations
08 Jun 1976
TL;DR: A new canonical circuit model is proposed, whose fixed topology contains all the essential inputr-output and control properties of any dc-todc switching converter, regardless of its detailed configuration, and by which different converters can be characterized in the form of a table conveniently stored in a computer data bank to provide a useful tool for computer aided design and optimization.
Abstract: A method for modelling switching-converter power stages is developed, whose starting point is the unified state-space representation of the switched networks and whose end result is either a complete state-space description or its equivalent small-signal low<-f requency linear circuit model. A new canonical circuit model is proposed, whose fixed topology contains all the essential inputr-output and control properties of any dc-todc switching converter, regardless of its detailed configuration, and by which different converters can be characterized in the form of a table conveniently stored in a computer data bank to provide a useful tool for computer aided design and optimization. The new canonical circuit model predicts that, in general;switching action introduces both zeros and poles into the duty ratio to output transfer function in addition to those from the effective filter network.
2,042 citations
TL;DR: In this article, a canonical circuit model is proposed, whose fixed topology contains all the essential input-output and control properties of any d.c.-to-d.c. switching converter, regardless of its detailed configuration, and by which different converters can be characterized in the form of a table conveniently stored in a computer data bank.
Abstract: A method for modelling switching-converter power stages is developed, whose starting-point is the unified state-space representation of the switched notworks and whose end result is either a complete state-space description or its equivalent small-signal low-frequency linear circuit model. A new canonical circuit model is proposed, whose fixed topology contains all the essential input-output and control properties of any d.c.-to-d.c. switching converter, regardless of its detailed configuration, and by which different converters can be characterized in the form of a table conveniently stored in a computer data bank to provide a useful tool for computer-aided design and optimization. The new canonical circuit model predicts that, in general, switching action introduces both zeros and poles into the duty ratio to output transfer function in addition to those from the effective filter network.
1,827 citations
Patent•
19 Jun 1996TL;DR: In this article, the authors present a controller that can cause the generator to supply a blended output signal alternating constantly between a first output signal across the output connections in which the radio frequency output voltage developed across output connections is limited to at least a first predetermined threshold value for cutting or vaporization of tissue, and a second output signal with a power supply coupled to the output stage for supplying power to output stage.
Abstract: In an electrosurgical generator for generating radio frequency power, the generator includes a radio frequency output stage having two or more output connections, and a power supply coupled to the output stage for supplying power to the output stage. A controller is operable to cause the generator to supply a blended output signal alternating constantly between a first output signal across the output connections in which the radio frequency output voltage developed across the output connections is limited to at least a first predetermined threshold value for cutting or vaporisation of tissue, and a second output signal across the output connections in which the radio frequency output voltage developed across the output connections is limited to a second threshold value for coagulation. There is also provided adjustment means, operable by a user of the electrosurgical generator, for changing between various preset settings for the blended signal, the preset settings each having a predetermined duty cycle of the blended signal that is limited to the first threshold value for cutting or vaporisation, and a predetermined duty cycle of the blended signal that is limited to the second threshold value for coagulation.
1,486 citations