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Lifetime Improvement of Wireless Sensor Network using Network Coded Adaptive Duty Cycle

Lifetime Improvement of Wireless Sensor Network using Network Coded Adaptive Duty Cycle

Wireless sensor network consists of automatic sensors, which have a limited power battery. Nodes which are present near the centralized collecting point will be in demand of much power which limits the overall network life time. The active area near to the sink node makes a bottleneck zone because of large traffic- flow which minimize the network lifetime in wireless sensor network. In this project, we introduce an adaptive duty cycle and encoding technique for minimizing energy consumption in the bottleneck zone .An efficient communication technique has been adopted in the bottleneck zone by combining adaptive duty cycle and encoding technique. Energy efficiency of the bottleneck zone increases due to more volume of data will be transmitted to the sink with the same number of transmissions. Hence the lifetime of wireless sensor network is enhanced. This work archive to enhance the energy efficiency of the bottleneck zone which leads to overall improvement of the network lifetime by considering a network coded adaptive duty cycle WSN. Linear Network coding is not simply relaying the packets of information they receive, the sensor nodes of a network take several packets and combine them together for transmission and applied in bottleneck zone. By applying the above techniques the overall life time of the node will finally increases. This proposed system investigates life time improvement approximately 8% - 14%, and minimizing energy consumption.
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Research on Maximum Power Point Algorithm Based on Adaptive Duty Cycle

Research on Maximum Power Point Algorithm Based on Adaptive Duty Cycle

or right side of MPP. Then we begin to calculate the value of ∆U*∆P. If ∆U*∆P>0, it indicates that the operating point is on the left side of MPP. To track the MPP, it is necessary to increase the operating voltage. On the other hand, if ∆U*∆P<0, the operating voltage should decrease. The operating voltage change in this paper is done by adjusting a step size ∆D ( b ! & ) to the duty cycle D of a DC-DC converter. The step size can be adjusted itself. When the operating point is far away from the maximum power point, a large step size can be used to improve the tracking speed (at this moment b & ! determines to use a big step size). When it is approaching the maximum power point, b ! & determines to use a small step size to ensure the tracking accuracy. So the modified P&O method can balance the contradiction between tracking speed and steady oscillation in traditional perturbation observation method. The flow chart of the modified perturbation observation algorithm is shown in Figure 2.
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Energy-Efficient Forest Fire Prediction Model based on Two-Stage Adaptive Duty-Cycled Hybrid X-MAC Protocol

Energy-Efficient Forest Fire Prediction Model based on Two-Stage Adaptive Duty-Cycled Hybrid X-MAC Protocol

Abstract: This paper proposes an adaptive duty cycle hybrid asynchronous MAC (ADX-MAC) protocol for energy-efficient forest fire prediction. The Asynchronous sensor network protocol, X- MAC protocol acquires additional environmental status details from each forest fire monitoring sensor for a given period, and then changes the duty cycle sleep interval to efficiently calculate forest fire occurrence risk according to the environment. Performance was verified experimentally, and the proposed ADX-MAC protocol improved throughput by 19% and was 24% more energy efficient compared to X-MAC protocol. The duty cycle was shortened as forest fires probability increased, ensuring forest fires were detected at faster cycle rate.
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Energy Constrained Duty Cycle Optimization for Wireless Implanted Communication Devices

Energy Constrained Duty Cycle Optimization for Wireless Implanted Communication Devices

Energy minimization is an important goal in wireless implanted communication devices. In this context, a cross-layer method is used to optimize parameters in different layers of OSI model, but, there are still several challenges affecting the optimization algorithm. The first point is the accurate energy model, and the second point is the suitable channel model exclude traditional free space channel model. In this paper, we establish a system level accurate energy consump- tion model and build a suitable channel model for implanted communication devices; analysis the energy-constrained duty cycle optimization with a cross-layer method. Simulation results reveal that adaptive duty cycle to minimize the energy consumption of the wireless implanted communication system is implemented based on accurate energy con- sumption model and channel model. Simulation results show a good performance on energy saving.
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Power at the expense of efficiency in contraction of white muscle fibres from dogfish Scyliorhinus canicula

Power at the expense of efficiency in contraction of white muscle fibres from dogfish Scyliorhinus canicula

Dependence of efficiency and power on stimulation phase For each stimulus duty cycle (duration of stimulation/cycle duration), the stimulus phase (timing of the start of stimulation relative to the start of shortening) was varied to find the stimulus phase that gave the highest efficiency. Fig. 2 shows these stimulation patterns in relation to the sinusoidal movement. Each horizontal bar shows, for one preparation, the period of stimulation in the position giving the highest efficiency. Results for different duty cycles are shown; the stimulus bars are arranged with the larger duty cycles at the top in each graph. The experiments were made with peak-to- peak amplitudes of 0.5 mm (0.067L 0 , solid stimulus bars) and
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Divergent mechanisms of acoustic mate recognition between closely related field cricket species (Teleogryllus spp )

Divergent mechanisms of acoustic mate recognition between closely related field cricket species (Teleogryllus spp )

selectivity for the pulse duty cycle in the trill portion of the calling song means and standard.. errors are presented.[r]

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A Novel Energy Efficient Routing for Data Intensive MANETs

A Novel Energy Efficient Routing for Data Intensive MANETs

ABSTRACT: Mobile ad hoc networks (MANETs) consist of a collection of wireless mobile nodes which dynamically exchange data among themselves without the need of fixed infrastructure or a wired backbone network. Energy consumption in MANET is one of the important issues in this research. Reliable data delivery in MANET consumes lot of energy. The efficient node-energy consumption in wireless ad hoc networks is essential as ad-hoc nodes operate with limited battery power. Routing protocol scheme for wireless networks are support by two essential requirements, minimize energy metrics or maximize network throughput. The objective of this paper is to minimise the energy expenditure of the network by using the concept of duty cycle and thereby increasing the throughput. The performance analysis and simulation are carried out using Network Simulator-2.
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Sliding   Mode  MPPT   Based Control For a Solar Photovoltaic system

Sliding   Mode  MPPT   Based Control For a Solar Photovoltaic system

MPPT operation. MPPT function controls DC-DC converter that accepts a DC input voltage and outputs a DC voltage higher, lower or same as the input voltage. For a boost converter, the output of the DC voltage will be higher than that of the input voltage. These converters uses intermediate energy storage components which includes inductors and capacitors which control the energy flow from the PV module to the load by continuously opening and closing of switch. The switch is an electronic device which operates in two states: on or off state. The input to the SMC-MPPT is the tracking error term i.e, the change in the reference voltage and PV voltage and the output to the SMC is the change in the duty ratio which will be given to the PWM generator.
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Tiger moth responses to a simulated bat attack: timing and duty cycle

Tiger moth responses to a simulated bat attack: timing and duty cycle

Assuming a fixed intensity of a single microclick and that bats function as perfect power integrators, an additional microclick within the bat receiver’s integration window would increase the perceived intensity of the moth signal by approximately 3·dB (Zwislocki, 1960; Au et al., 1988). However, given the large variation in microclick intensity and duration both across species and even within a single modulation cycle of one moth, the relationship between number of microclicks and intensity is not that clearcut. As in the regression model, an animal receiver would perceive more microclicks per unit time as more intense. The details of such a relationship would also depend upon the behavioral integration time of the receiver. Using a double click paradigm this value has been estimated at 0.2·ms in Megaderma lyra (Weißenbacher et al., 2002) and 2.4·ms in Eptesicus fuscus (Surlykke and Bojesen, 1996). In humans, integration time may depend upon stimulus type (for a review, see Brown and Maloney, 1986). Although, in M. lyra integration time has been shown to be independent of echolocation use (Weißenbacher et al., 2002), it remains unclear how different stimulus types influence these processes in bats. The above studies have also shown some variation across individuals. Taken together these results indicate that integration time likely varies both across species and situations. Our use of 100·ms to standardize intensity measurements allows a comparison of relative values but cannot predict the perceived intensity by the bat receiver.
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A Bi Polar Triple Output Converter with Duty Cycle Estimation

A Bi Polar Triple Output Converter with Duty Cycle Estimation

This paper proposes a triple output converter with buck, boost and inverted outputs and con- trolled through duty cycle estimation. In the existing converter, to generate the negative output, the power flows from load to the supply (from the boost output to the supply) during a part of the cycle, which increases cycle time and losses, and reduces the power level. To overcome this, a modified converter with a main and an auxiliary inductance and with reduced number of switches is proposed. The converter can operate in continuous and discontinuous conduction modes and the outputs can be independently controlled. An analysis of the converter is done for both modes. A simplified control of the converter through duty cycle estimation is suggested to regulate the outputs, which does not have the constraint that the current ripple has to be small. The control works both in the continuous and discontinuous modes. The simulation results closely match with the analysis. A prototype of the converter is constructed with a Spartan FPGA system and results have been presented.
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A Wide Range All Digital Feedback Duty Cycle Corrector

A Wide Range All Digital Feedback Duty Cycle Corrector

Initially the duty cycle adjuster does not execute any operation. It passes input as output. Duty cycle detector detects the duty rate of an output clock and checks whether the duty rate is greater or lesser than 50%. Based on that it will produce output signal as comp. When the MSAR controller completes their binary search algorithm it will automatically enters into a counter mode. Therefore, closed loop operation has been maintained. Finally, the signal End goes to

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Energy optimal scheduling in low duty cycle sensor networks

Energy optimal scheduling in low duty cycle sensor networks

Abstract—Energy consumption of a wireless sensor node mainly depends on the amount of time the node spends in each of the high power active (e.g., transmit, receive) and low power sleep modes. It has been well established that in order to prolong node’s lifetime the duty-cycle of the node should be low. However, low power sleep modes usually have low current draw but high energy cost while switching to the active mode with a higher current draw. In this work, we investigate a MaxWeight- like opportunistic sleep-active scheduling algorithm that takes into account time- varying channel and traffic conditions. We show that our algorithm is energy optimal in the sense that the proposed ESS algorithm can achieve an energy consumption which is arbitrarily close to the global minimum solution. Simulation studies are provided to confirm the theoretical results.
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Design of PWM with Variable Duty Cycle for Efficient Power Analysis

Design of PWM with Variable Duty Cycle for Efficient Power Analysis

This paper proposes to spread the switching of clock tree drivers in an try to decrease the peakcurrent, while preserving the clock sign pleasant and low skew [r]

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Driving cycle for small and medium duty engine: case study of Ipoh

Driving cycle for small and medium duty engine: case study of Ipoh

P.Khumla et al.,(2010) construct driving cycle to fuel consumption and emission of motorcycle using data logger during weekend, weekend and weekday-weekend periods by the statistical method. For developed driving cycle, it collecting data using micro-trip technique and generated nine target parameter such as average speed, average running speed, time spent in acceleration, time spent in deceleration, time spent at idle, time spent at cruise, average acceleration, average deceleration and positive acceleration kinetic energy. There are four steps that involved in methodology; (1) road selection, (2) collection of speed time data, (3) data analysis and, (4) generation of driving cycle. The resulting of the cycle is 7.647 km in length, maximum velocity 70 km/h, maximum acceleration 3.6 , maximum deceleration -2.22 , and 1145 s in time duration and involves 6 intermediate stops as shown in (Figure 2.15)
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Timing matters: tuning the mechanics of a muscle–tendon unit by adjusting stimulation phase during cyclic contractions

Timing matters: tuning the mechanics of a muscle–tendon unit by adjusting stimulation phase during cyclic contractions

Recent muscle-level studies of terrestrial gait have observed that in the distal, more compliant MTUs of many species, including humans, CEs (i.e. active muscle) are in fact used as a strut to allow the SEEs (i.e. tendon, aponeurosis) within MTUs to stretch and recoil during cyclic limb motions (Roberts et al., 1997; Biewener et al., 1998; Fukunaga et al., 2001; Ishikawa et al., 2005; Takeshita et al., 2006; Dean and Kuo, 2011; Farris and Sawicki, 2012; Farris et al., 2013). In other words, CE length changes are decoupled from MTU trajectories via SEE compliance, and CE – SEE interaction is ‘ tuned ’ to cycle large amounts of energy in tendons and aponeuroses while the CE itself remains relatively isometric (Robertson and Sawicki, 2014). This ‘ tuned ’ pattern facilitates length change dynamics suitable for high CE force production, which, in turn, require relatively smaller active volumes of muscle to generate force during each stride (Roberts et al., 1997; Gabaldon et al., 2008).
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Light-Duty Vehicle Emissions Control: A Brief Introduction to the China 6 Emissions Standard269-278

Light-Duty Vehicle Emissions Control: A Brief Introduction to the China 6 Emissions Standard269-278

China has been the world’s largest new vehicle market since 2009 and new vehicle sales exceeded 28 million in 2016, among which more than 87% were light-duty vehicles (LDV). In order to reduce emissions and control air pollution China has recently adopted the China 6 emissions standard for LDV which is 50% more stringent than China 5. Besides strengthening the tailpipe emissions limits, China 6 changes the emissions test driving cycle to the Worldwide Harmonised Light-Duty Vehicle Test Cycle (WLTC), adds real road emissions requirements and significantly strengthens evaporative emissions control. This paper introduces the standard development background, summarises the key technical improvements and discusses the areas for further improvements in future.
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Enhancement of Lifetime Using Network Coding and Duty Cycle at Wireless Sensor Network

Enhancement of Lifetime Using Network Coding and Duty Cycle at Wireless Sensor Network

The key challenge in networks of energy constrained wireless integrated sensor nodes is maximizing network lifetime. In a wireless sensor network (WSN), the area around the Sink forms a bottleneck zone where the traffic flow is maximum. Thus, the lifetime of the WSN network is dictated by the lifetime of the bottleneck zone. By combining duty cycle and network coding it gives better results than individual network coding and duty cycle. As existing methods consist single hop communication between network coder node and sink this paper focused on the multi-hop system between network coder nodes and sink with same coding as in existing methods. In single hop network coder it transmits more number of packets. So more energy required to transmit packets. In multi hop system less number of packets are transmitted than single hop so that energy consumption is also less. In both methods retransmissions are saved and that are approximately same. It may provide efficient solution for large networks for enhance the life.
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FPGA-Based Analog-to-Digital Conversion via   Optimal Duty-Cycle Modulation

FPGA-Based Analog-to-Digital Conversion via Optimal Duty-Cycle Modulation

ADC architecture founded on the DCM (duty-cycle modulation) principle, has been studied and well tested with satisfactory results in [4, 5]. However, the following technological problems were outlined: Use of a PC (personal computer) as the DSP (digital-signal-processing) core for real-time oversampling high frequency on/off modulating signals, unreliability of the PC-based clock required for the oversampling process, and implementation of the digital decimation process as a Visual Basic application program. Given these technological problems, it is worth noting that the limitations related to the DCM-ADC architecture, relies on the PC-based environment used for digital signal processing tasks. Indeed, many studies conducted in most recent papers indicate that, the DCM principle provides numerous relevant technical properties and high quality [6, 7], while numerous intricate weaknesses are hidden behind the popular sigma-delta ADC architecture, e.g., higher structural complexity, higher order n-bit decimation filter for reaching a good accuracy, lack of exact analytical models for rigorous design and analysis purposes, and more. It is worth noting also that, although the DCM principle has also been used satisfactory beyond ADC application areas, e.g., DAC (digital-to-analog converters) [8-11], signal transmission [12, 13], and power electronics [14-16], little attention has been devoted to the ODCM problem studied in [17], under Matlab/Simulink framework.
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Voltage Regulation and Over Voltage Protection for High Gain High-Efficiency DC-DC Converter

Voltage Regulation and Over Voltage Protection for High Gain High-Efficiency DC-DC Converter

Fig.3. is a High step-up converter with coupled inductor is proposed in [5]. A coupled inductor is a device primarily used for energy storage during a power converter switching cycle; the power entering the coupled-inductor is not the same as the power leaving it in a given instant. Coupled inductor can serve as a transformer that is used to enlarge the voltage gain in non-isolated DC-DC converter [6]. Converter with coupled inductors can easily achieve high step-up voltage gain utilising low R DS - ON switches at low power level. The coupled inductor based DC-DC
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Effect of the duty cycle on the spark-plug plasma synthetic jet actuator

Effect of the duty cycle on the spark-plug plasma synthetic jet actuator

In order to present characteristic of the developed SPSJ actuators, instantaneous velocity measurement is being carried out with the help of the hot wire anemometer in quiescent air at the probe location above 6 mm from the top surface of the cap. As illustrated in figure 4, the instantaneous velocity distribution as a function of time was presented for different duty cycle changing between 10% and 90% in driving frequency of 0.5 Hz. Peak instantaneous velocity is as high as 175 m/s which was obtained at duty cycle of 90%. On the other hand, in the velocity time history, some of the jet velocities weren’t exactly acquired rightly because of insufficient sampling frequency of the hot-wire anemometer. Therefore, the peak jet velocities obtained randomly due to very small jet formation time according to efficient sampling period. As clearly shown in figure 4, the used low-cost high voltage power supply has instable characteristic during the elapsed time. It sometimes provides enough energy to SPSJ actuator but it doesn’t. In this case, instantaneous velocities acutely change. As duty cycle decrease from 90% to 10%, peak velocities significantly diminish. At the low duty cycle, the discharge time is too short in order to obtain enough energy for producing plasma in comparison with other duty cycle rate; therefore the produced plasma by giving energy to the cavity volume generates the low jet velocity.
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