Optimization of ultra-low-power CMOS transistors

International Nuclear Information System (INIS)

Stockinger, M.

2000-01-01

Ultra-low-power CMOS integrated circuits have constantly gained importance due to the fast growing portable electronics market. High-performance applications like mobile telephones ask for high-speed computations and low stand-by power consumption to increase the actual operating time. This means that transistors with low leakage currents and high drive currents have to be provided. Common fabrication methods will soon reach their limits if the on-chip feature size of CMOS technology continues to shrink at this very fast rate. New device architectures will help to keep track with the roadmap of the semiconductor industry. Especially doping profiles offer much freedom for performance improvements as they determine the 'inner functioning' of a transistor. In this work automated doping profile optimization is performed on MOS transistors within the TCAD framework SIESTA. The doping between and under the source/drain wells is discretized on an orthogonal optimization grid facilitating almost arbitrary two-dimensional shapes. A linear optimizer issued to find the optimum doping profile by variation of the doping parameters utilizing numerical device simulations with MINIMOS-NT. Gaussian functions are used in further optimization runs to make the doping profiles smooth. Two device generations are considered, one with 0.25 μm, the other with 0.1 μm gate length. The device geometries and source/drain doping profiles are kept fixed during optimization and supply voltages are chosen suitable for ultra-low-power purposes. In a first optimization study the drive current of NMOS transistors is maximized while keeping the leakage current below a limit of 1 pA/μm. This results in peaking channel doping devices (PCD) with narrow doping peaks placed asymmetrically in the channel. Drive current improvements of 45 % and 71 % for the 0.25 μm and 0.1 μm devices, respectively, are achieved compared to uniformly doped devices. The PCD device is studied in detail and explanations for

Design of an ultra-low-power digital processor for passive UHF RFID tags

Energy Technology Data Exchange (ETDEWEB)

Shi Wanggen; Zhuang Yiqi; Li Xiaoming; Wang Xianghua; Jin Zhao; Wang Dan, E-mail: wanggen_shi@163.co [Key Laboratory of the Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, Institute of Microelectronics, Xidian University, Xi' an 710071 (China)

2009-04-15

A new architecture of digital processors for passive UHF radio-frequency identification tags is proposed. This architecture is based on ISO/IEC 18000-6C and targeted at ultra-low power consumption. By applying methods like system-level power management, global clock gating and low voltage implementation, the total power of the design is reduced to a few microwatts. In addition, an innovative way for the design of a true RNG is presented, which contributes to both low power and secure data transaction. The digital processor is verified by an integrated FPGA platform and implemented by the Synopsys design kit for ASIC flows. The design fits different CMOS technologies and has been taped out using the 2P4M 0.35 mum process of Chartered Semiconductor.

Ultra low power signal oriented approach for wireless health monitoring.

Science.gov (United States)

Marinkovic, Stevan; Popovici, Emanuel

2012-01-01

In recent years there is growing pressure on the medical sector to reduce costs while maintaining or even improving the quality of care. A potential solution to this problem is real time and/or remote patient monitoring by using mobile devices. To achieve this, medical sensors with wireless communication, computational and energy harvesting capabilities are networked on, or in, the human body forming what is commonly called a Wireless Body Area Network (WBAN). We present the implementation of a novel Wake Up Receiver (WUR) in the context of standardised wireless protocols, in a signal-oriented WBAN environment and present a novel protocol intended for wireless health monitoring (WhMAC). WhMAC is a TDMA-based protocol with very low power consumption. It utilises WBAN-specific features and a novel ultra low power wake up receiver technology, to achieve flexible and at the same time very low power wireless data transfer of physiological signals. As the main application is in the medical domain, or personal health monitoring, the protocol caters for different types of medical sensors. We define four sensor modes, in which the sensors can transmit data, depending on the sensor type and emergency level. A full power dissipation model is provided for the protocol, with individual hardware and application parameters. Finally, an example application shows the reduction in the power consumption for different data monitoring scenarios.

Design and Analysis of Double-Gate MOSFETs for Ultra-Low Power Radio Frequency Identification (RFID: Device and Circuit Co-Design

Directory of Open Access Journals (Sweden)

Tony T. Kim

2011-07-01

Full Text Available Recently, double-gate MOSFETs (DGMOSFETs have been shown to be more optimal for ultra-low power circuit design due to the improved subthreshold slope and the reduced leakage current compared to bulk CMOS. However, DGMOSFETs for subthreshold circuit design have not been much explored in comparison to those for strong inversion-based design. In this paper, various configurations of DGMOSFETs, such as tied/independent gates and symmetric/asymmetric gate oxide thickness are explored for ultra-low power and high efficient radio frequency identification (RFID design. Comparison of bulk CMOS with DGMOSFETs has been conducted in ultra-low power subthreshold digital logic design and rectifier design, emphasizing the scope of the nano-scale DGMOSFET technology for future ultra-low power systems. The DGMOSFET-based subthreshold logic improves energy efficiency by more than 40% compared to the bulk CMOS-based logic at 32 nm. Among the various DGMOSFET configurations for RFID rectifiers, symmetric tied-gate DGMOSFET has the best power conversion efficiency and the lowest power consumption.

Design of an ultra-low-power digital processor for passive UHF RFID tags

International Nuclear Information System (INIS)

Shi Wanggen; Zhuang Yiqi; Li Xiaoming; Wang Xianghua; Jin Zhao; Wang Dan

2009-01-01

A new architecture of digital processors for passive UHF radio-frequency identification tags is proposed. This architecture is based on ISO/IEC 18000-6C and targeted at ultra-low power consumption. By applying methods like system-level power management, global clock gating and low voltage implementation, the total power of the design is reduced to a few microwatts. In addition, an innovative way for the design of a true RNG is presented, which contributes to both low power and secure data transaction. The digital processor is verified by an integrated FPGA platform and implemented by the Synopsys design kit for ASIC flows. The design fits different CMOS technologies and has been taped out using the 2P4M 0.35 μm process of Chartered Semiconductor.

Ultra-Low-Power Design and Hardware Security Using Emerging Technologies for Internet of Things

Directory of Open Access Journals (Sweden)

Jiann-Shiun Yuan

2017-09-01

Full Text Available In this review article for Internet of Things (IoT applications, important low-power design techniques for digital and mixed-signal analog–digital converter (ADC circuits are presented. Emerging low voltage logic devices and non-volatile memories (NVMs beyond CMOS are illustrated. In addition, energy-constrained hardware security issues are reviewed. Specifically, light-weight encryption-based correlational power analysis, successive approximation register (SAR ADC security using tunnel field effect transistors (FETs, logic obfuscation using silicon nanowire FETs, and all-spin logic devices are highlighted. Furthermore, a novel ultra-low power design using bio-inspired neuromorphic computing and spiking neural network security are discussed.

An ultra-low power output capacitor-less low-dropout regulator with slew-rate-enhanced circuit

Science.gov (United States)

Cheng, Xin; Zhang, Yu; Xie, Guangjun; Yang, Yizhong; Zhang, Zhang

2018-03-01

An ultra-low power output-capacitorless low-dropout (LDO) regulator with a slew-rate-enhanced (SRE) circuit is introduced. The increased slew rate is achieved by sensing the transient output voltage of the LDO and then charging (or discharging) the gate capacitor quickly. In addition, a buffer with ultra-low output impedance is presented to improve line and load regulations. This design is fabricated by SMIC 0.18 μm CMOS technology. Experimental results show that, the proposed LDO regulator only consumes an ultra-low quiescent current of 1.2 μA. The output current range is from 10 μA to 200 mA and the corresponding variation of output voltage is less than 40 mV. Moreover, the measured line regulation and load regulation are 15.38 mV/V and 0.4 mV/mA respectively. Project supported by the National Natural Science Foundation of China (Nos. 61401137, 61404043, 61674049).

Power optimization in body sensor networks: the case of an autonomous wireless EMG sensor powered by PV-cells.

Science.gov (United States)

Penders, J; Pop, V; Caballero, L; van de Molengraft, J; van Schaijk, R; Vullers, R; Van Hoof, C

2010-01-01

Recent advances in ultra-low-power circuits and energy harvesters are making self-powered body sensor nodes a reality. Power optimization at the system and application level is crucial in achieving ultra-low-power consumption for the entire system. This paper reviews system-level power optimization techniques, and illustrates their impact on the case of autonomous wireless EMG monitoring. The resulting prototype, an Autonomous wireless EMG sensor power by PV-cells, is presented.

Magnetic Random Access Memory based non-volatile asynchronous Muller cell for ultra-low power autonomous applications

Science.gov (United States)

Di Pendina, G.; Zianbetov, E.; Beigne, E.

2015-05-01

Micro and nano electronic integrated circuit domain is today mainly driven by the advent of the Internet of Things for which the constraints are strong, especially in terms of power consumption and autonomy, not only during the computing phases but also during the standby or idle phases. In such ultra-low power applications, the circuit has to meet new constraints mainly linked to its changing energetic environment: long idle phases, automatic wake up, data back-up when the circuit is sporadically turned off, and ultra-low voltage power supply operation. Such circuits have to be completely autonomous regarding their unstable environment, while remaining in an optimum energetic configuration. Therefore, we propose in this paper the first MRAM-based non-volatile asynchronous Muller cell. This cell has been simulated and characterized in a very advanced 28 nm CMOS fully depleted silicon-on-insulator technology, presenting good power performance results due to an extremely efficient body biasing control together with ultra-wide supply voltage range from 160 mV up to 920 mV. The leakage current can be reduced to 154 pA thanks to reverse body biasing. We also propose an efficient standard CMOS bulk version of this cell in order to be compatible with different fabrication processes.

Magnetic Random Access Memory based non-volatile asynchronous Muller cell for ultra-low power autonomous applications

Energy Technology Data Exchange (ETDEWEB)

Di Pendina, G., E-mail: gregory.dipendina@cea.fr, E-mail: eldar.zianbetov@cea.fr, E-mail: edith.beigne@cea.fr; Zianbetov, E., E-mail: gregory.dipendina@cea.fr, E-mail: eldar.zianbetov@cea.fr, E-mail: edith.beigne@cea.fr [Univ. Grenoble Alpes, INAC-SPINTEC, F-38000 Grenoble (France); CNRS, SPINTEC, F-38000 Grenoble (France); CEA, INAC-SPINTEC, F-38000 Grenoble (France); Beigne, E., E-mail: gregory.dipendina@cea.fr, E-mail: eldar.zianbetov@cea.fr, E-mail: edith.beigne@cea.fr [Univ. Grenoble Alpes, CEA, LETI, F-38000 Grenoble (France)

2015-05-07

Micro and nano electronic integrated circuit domain is today mainly driven by the advent of the Internet of Things for which the constraints are strong, especially in terms of power consumption and autonomy, not only during the computing phases but also during the standby or idle phases. In such ultra-low power applications, the circuit has to meet new constraints mainly linked to its changing energetic environment: long idle phases, automatic wake up, data back-up when the circuit is sporadically turned off, and ultra-low voltage power supply operation. Such circuits have to be completely autonomous regarding their unstable environment, while remaining in an optimum energetic configuration. Therefore, we propose in this paper the first MRAM-based non-volatile asynchronous Muller cell. This cell has been simulated and characterized in a very advanced 28 nm CMOS fully depleted silicon-on-insulator technology, presenting good power performance results due to an extremely efficient body biasing control together with ultra-wide supply voltage range from 160 mV up to 920 mV. The leakage current can be reduced to 154 pA thanks to reverse body biasing. We also propose an efficient standard CMOS bulk version of this cell in order to be compatible with different fabrication processes.

Magnetic Random Access Memory based non-volatile asynchronous Muller cell for ultra-low power autonomous applications

International Nuclear Information System (INIS)

Di Pendina, G.; Zianbetov, E.; Beigne, E.

2015-01-01

Micro and nano electronic integrated circuit domain is today mainly driven by the advent of the Internet of Things for which the constraints are strong, especially in terms of power consumption and autonomy, not only during the computing phases but also during the standby or idle phases. In such ultra-low power applications, the circuit has to meet new constraints mainly linked to its changing energetic environment: long idle phases, automatic wake up, data back-up when the circuit is sporadically turned off, and ultra-low voltage power supply operation. Such circuits have to be completely autonomous regarding their unstable environment, while remaining in an optimum energetic configuration. Therefore, we propose in this paper the first MRAM-based non-volatile asynchronous Muller cell. This cell has been simulated and characterized in a very advanced 28 nm CMOS fully depleted silicon-on-insulator technology, presenting good power performance results due to an extremely efficient body biasing control together with ultra-wide supply voltage range from 160 mV up to 920 mV. The leakage current can be reduced to 154 pA thanks to reverse body biasing. We also propose an efficient standard CMOS bulk version of this cell in order to be compatible with different fabrication processes

Development of Ultra-Low Power Metal Oxide Sensors and Arrays for Embedded Applications

Science.gov (United States)

Lutz, Brent; Wind, Rikard; Kostelecky, Clayton; Routkevitch, Dmitri; Deininger, Debra

2011-09-01

Metal oxide semiconductor sensors are widely used as individual sensors and in arrays, and a variety of designs for low power microhotplates have been demonstrated.1 Synkera Technologies has developed an embeddable chemical microsensor platform, based on a unique ceramic MEMS technology, for practical implementation in cell phones and other mobile electronic devices. Key features of this microsensor platform are (1) small size, (2) ultra-low power consumption, (3) high chemical sensitivity, (4) accurate response to a wide-range of threats, and (5) low cost. The sensor platform is enabled by a combination of advances in ceramic micromachining, and precision deposition of sensing films inside the high aspect ratio pores of anodic aluminum oxide (AAO).

An ultra-small, low-power, all-optical flip-flop memory on a silicon chip

DEFF Research Database (Denmark)

Liu, Liu; Kumar, R.; Huybrechts, K.

2010-01-01

Ultra-small, low-power, all-optical switching and memory elements, such as all-optical flip-flops, as well as photonic integrated circuits of many such elements, are in great demand for all-optical signal buffering, switching and processing. Silicon-on-insulator is considered to be a promising......-flop working in a continuous-wave regime with an electrical power consumption of a few milliwatts, allowing switching in 60 ps with 1.8 fJ optical energy. The total power consumption and the device size are, to the best of our knowledge, the smallest reported to date at telecom wavelengths. This is also...

Experiences of ultra-low-crud high-nickel control in Onagawa nuclear power station

International Nuclear Information System (INIS)

Saito, M.; Goto, Y.; Shinomiya, T.; Sato, M.; Yamazaki, K.; Hirasawa, H.; Yotsuyanagi, T.

2002-01-01

We have adopted various countermeasures for worker dose reduction to plants in Onagawa Nuclear Power Station. ''Ni/Fe ratio control'' has been adopted to Unit 1, and ''ultra-low-crud high-nickel control'' has been adopted to Unit 2 and 3, along with other countermeasures like wide utilization of low Co materials, for the purpose of dose rate reduction of primary recirculation piping which is thought to be one of the main exposure sources. In this paper, we describe, first, the reason and background that ultra-low-crud high-nickel control has been adopted to Unit 2, and, second, water chemistry of Unit 2 up to the 5. cycle under ultra-low-crud high-nickel control compared to that of Unit 1 under Ni/Fe ratio control. Following those, we show brief analysis of the fuel crud of Unit 2 and water chemistry of Unit 3 only at the startup stage. (authors)

An Analog Circuit Approximation of the Discrete Wavelet Transform for Ultra Low Power Signal Processing in Wearable Sensor Nodes

OpenAIRE

Casson, Alexander J.

2015-01-01

Ultra low power signal processing is an essential part of all sensor nodes, and particularly so in emerging wearable sensors for biomedical applications. Analog signal processing has an important role in these low power, low voltage, low frequency applications, and there is a key drive to decrease the power consumption of existing analog domain signal processing and to map more signal processing approaches into the analog domain. This paper presents an analog domain signal processing circuit ...

An Analog Circuit Approximation of the Discrete Wavelet Transform for Ultra Low Power Signal Processing in Wearable Sensor Nodes.

Science.gov (United States)

Casson, Alexander J

2015-12-17

Ultra low power signal processing is an essential part of all sensor nodes, and particularly so in emerging wearable sensors for biomedical applications. Analog signal processing has an important role in these low power, low voltage, low frequency applications, and there is a key drive to decrease the power consumption of existing analog domain signal processing and to map more signal processing approaches into the analog domain. This paper presents an analog domain signal processing circuit which approximates the output of the Discrete Wavelet Transform (DWT) for use in ultra low power wearable sensors. Analog filters are used for the DWT filters and it is demonstrated how these generate analog domain DWT-like information that embeds information from Butterworth and Daubechies maximally flat mother wavelet responses. The Analog DWT is realised in hardware via g(m)C circuits, designed to operate from a 1.3 V coin cell battery, and provide DWT-like signal processing using under 115 nW of power when implemented in a 0.18 μm CMOS process. Practical examples demonstrate the effective use of the new Analog DWT on ECG (electrocardiogram) and EEG (electroencephalogram) signals recorded from humans.

An Analog Circuit Approximation of the Discrete Wavelet Transform for Ultra Low Power Signal Processing in Wearable Sensor Nodes

Directory of Open Access Journals (Sweden)

Alexander J. Casson

2015-12-01

Full Text Available Ultra low power signal processing is an essential part of all sensor nodes, and particularly so in emerging wearable sensors for biomedical applications. Analog signal processing has an important role in these low power, low voltage, low frequency applications, and there is a key drive to decrease the power consumption of existing analog domain signal processing and to map more signal processing approaches into the analog domain. This paper presents an analog domain signal processing circuit which approximates the output of the Discrete Wavelet Transform (DWT for use in ultra low power wearable sensors. Analog filters are used for the DWT filters and it is demonstrated how these generate analog domain DWT-like information that embeds information from Butterworth and Daubechies maximally flat mother wavelet responses. The Analog DWT is realised in hardware via g m C circuits, designed to operate from a 1.3 V coin cell battery, and provide DWT-like signal processing using under 115 nW of power when implemented in a 0.18 μm CMOS process. Practical examples demonstrate the effective use of the new Analog DWT on ECG (electrocardiogram and EEG (electroencephalogram signals recorded from humans.

Ultra-low power anti-crosstalk collision avoidance light detection and ranging using chaotic pulse position modulation approach

International Nuclear Information System (INIS)

Hao Jie; Gong Ma-li; Du Peng-fei; Lu Bao-jie; Zhang Fan; Zhang Hai-tao; Fu Xing

2016-01-01

A novel concept of collision avoidance single-photon light detection and ranging (LIDAR) for vehicles has been demonstrated, in which chaotic pulse position modulation is applied on the transmitted laser pulses for robust anti-crosstalk purposes. Besides, single-photon detectors (SPD) and time correlated single photon counting techniques are adapted, to sense the ultra-low power used for the consideration of compact structure and eye safety. Parameters including pulse rate, discrimination threshold, and number of accumulated pulses have been thoroughly analyzed based on the detection requirements, resulting in specified receiver operating characteristics curves. Both simulation and indoor experiments were performed to verify the excellent anti-crosstalk capability of the presented collision avoidance LIDAR despite ultra-low transmitting power. (paper)

Capacitively coupled EMG detection via ultra-low-power microcontroller STFT.

Science.gov (United States)

Roland, Theresa; Baumgartner, Werner; Amsuess, Sebastian; Russold, Michael F

2017-07-01

As motion artefacts are a major problem with electromyography sensors, a new algorithm is developed to differentiate artefacts to contraction EMG. The performance of myoelectric prosthesis is increased with this algorithm. The implementation is done for an ultra-low-power microcontroller with limited calculation resources and memory. Short Time Fourier Transformation is used to enable real-time application. The sum of the differences (SOD) of the currently measured EMG to a reference contraction EMG is calculated. The SOD is a new parameter introduced for EMG classification. The satisfactory error rates are determined by measurements done with the capacitively coupling EMG prototype, recently developed by the research group.

A fully integrated, wide-load-range, high-power-conversion-efficiency switched capacitor DC-DC converter with adaptive bias comparator for ultra-low-power power management integrated circuit

Science.gov (United States)

Asano, Hiroki; Hirose, Tetsuya; Kojima, Yuta; Kuroki, Nobutaka; Numa, Masahiro

2018-04-01

In this paper, we present a wide-load-range switched-capacitor DC-DC buck converter with an adaptive bias comparator for ultra-low-power power management integrated circuit. The proposed converter is based on a conventional one and modified to operate in a wide load range by developing a load current monitor used in an adaptive bias comparator. Measurement results demonstrated that our proposed converter generates a 1.0 V output voltage from a 3.0 V input voltage at a load of up to 100 µA, which is 20 times higher than that of the conventional one. The power conversion efficiency was higher than 60% in the load range from 0.8 to 100 µA.

FY 2000 report on the development of ultra low loss power element technology. Commercialization of next generation power semiconductor device; 2000 nendo choteisonshitsu denryoku soshi gijutsu kaihatsu seika hokokusho. Jisedai power handotai device jitsuyoka chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

For the purpose of contributing to the promotion of development of ultra low loss power element technology, survey was conducted on the present situation, future, etc. of various technologies/systems related to power semiconductor devices. In the industrial equipment field, it is predicted that power semiconductor devices will be increased in the field of application by enlargement of the defense field of IGBT, new MOS structure elements, etc. In the field of home appliances, possibilities are expected of switching loss reduction and electric noise reduction by making SiC high speed diode. As to the space photovoltaic power generation, SiC is expected for various semiconductors such as solar cells, FET for transmitter/amplifier of radio power electric transmission use micro waves, etc. Concerning the radio communication system plan using stratosphere platform, there are technical problems on communication equipment such as antenna and RF circuit, and the role of SiC device is expected to be large. The society where the electrification rate is 80% and fuel cell vehicles are used is a new paradigm, and it is necessary and indispensable to commercialize ultra low loss power elements using SiC. (NEDO)

A Comparative Study of Analog Voltage-mode Control Methods for Ultra-Fast Tracking Power Supplies

DEFF Research Database (Denmark)

Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

2007-01-01

This paper presents a theoretical and experimental comparison of the standard PWM/PID voltage-mode control method for single-phase buck converters with two highperformance self-oscillating (a.k.a. sliding mode) control methods. The application considered is ultra-fast tracking power supplies...... (UFTPSs) for RF power amplifiers, where the switching converter needs to track a varying reference voltage precisely and quickly while maintaining low output impedance. The small-signal analyses performed on the different controllers show that the hysteretic-type controller can achieve the highest loop...

ePave: A Self-Powered Wireless Sensor for Smart and Autonomous Pavement.

Science.gov (United States)

Xiao, Jian; Zou, Xiang; Xu, Wenyao

2017-09-26

"Smart Pavement" is an emerging infrastructure for various on-road applications in transportation and road engineering. However, existing road monitoring solutions demand a certain periodic maintenance effort due to battery life limits in the sensor systems. To this end, we present an end-to-end self-powered wireless sensor-ePave-to facilitate smart and autonomous pavements. The ePave system includes a self-power module, an ultra-low-power sensor system, a wireless transmission module and a built-in power management module. First, we performed an empirical study to characterize the piezoelectric module in order to optimize energy-harvesting efficiency. Second, we developed an integrated sensor system with the optimized energy harvester. An adaptive power knob is designated to adjust the power consumption according to energy budgeting. Finally, we intensively evaluated the ePave system in real-world applications to examine the system's performance and explore the trade-off.

Stretchers and compressors for ultra-high power laser systems

Energy Technology Data Exchange (ETDEWEB)

Yakovlev, I V [Institute of Applied Physics, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

2014-05-30

This review is concerned with pulse stretchers and compressors as key components of ultra-high power laser facilities that take advantage of chirped-pulse amplification. The potentialities, characteristics, configurations and methods for the matching and alignment of these devices are examined, with particular attention to the history of the optics of ultra-short, ultra-intense pulses before and after 1985, when the chirped-pulse amplification method was proposed, which drastically changed the view of the feasibility of creating ultra-high power laser sources. The review is intended primarily for young scientists and experts who begin to address the amplification and compression of chirped pulses, experts in laser optics and all who are interested in scientific achievements in the field of ultra-high power laser systems. (review)

Power Management and SRAM for Energy-Autonomous and Low-Power Systems

Science.gov (United States)

Chen, Gregory K.

We demonstrate the two first-known, complete, self-powered millimeter-scale computer systems. These microsystems achieve zero-net-energy operation using solar energy harvesting and ultra-low-power circuits. A medical implant for monitoring intraocular pressure (IOP) is presented as part of a treatment for glaucoma. The 1.5mm3 IOP monitor is easily implantable because of its small size and measures IOP with 0.5mmHg accuracy. It wirelessly transmits data to an external wand while consuming 4.70nJ/bit. This provides rapid feedback about treatment efficacies to decrease physician response time and potentially prevent unnecessary vision loss. A nearly-perpetual temperature sensor is presented that processes data using a 2.1muW near-threshold ARMRTM Cortex-M3(TM) muP that provides a widely-used and trusted programming platform. Energy harvesting and power management techniques for these two microsystems enable energy-autonomous operation. The IOP monitor harvests 80nW of solar power while consuming only 5.3nW, extending lifetime indefinitely. This allows the device to provide medical information for extended periods of time, giving doctors time to converge upon the best glaucoma treatment. The temperature sensor uses on-demand power delivery to improve low-load dc-dc voltage conversion efficiency by 4.75x. It also performs linear regulation to deliver power with low noise, improved load regulation, and tight line regulation. Low-power high-throughput SRAM techniques help millimeter-scale microsystems meet stringent power budgets. VDD scaling in memory decreases energy per access, but also decreases stability margins. These margins can be improved using sizing, VTH selection, and assist circuits, as well as new bitcell designs. Adaptive Crosshairs modulation of SRAM power supplies fixes 70% of parametric failures. Half-differential SRAM design improves stability, reducing VMIN by 72mV. The circuit techniques for energy autonomy presented in this dissertation enable

Energy scavenging sensors for ultra-low power sensor networks

Science.gov (United States)

O'Brien, Dominic C.; Liu, Jing Jing; Faulkner, Grahame E.; Vachiramon, Pithawat; Collins, Steve; Elston, Steven J.

2010-08-01

The 'internet of things' will require very low power wireless communications, preferably using sensors that scavenge power from their environment. Free space optics allows communications over long ranges, with simple transceivers at each end, offering the possibility of low energy consumption. In addition there can be sufficient energy in the communications beam to power simple terminals. In this paper we report experimental results from an architecture that achieves this. A base station that tracks sensors in its coverage area and communicates with them using low divergence optical beams is presented. Sensor nodes use modulated retro-reflectors to communicate with the base station, and the nodes are powered by the illuminating beam. The paper presents design and implementation details, as well as future directions for this work.

Extreme low-power mixed signal IC design

CERN Document Server

Tajalli, Armin

2010-01-01

This book describes a completely novel class of techniques for designing ultra-low-power integrated circuits (ICs). In many applications such as battery operated systems and battery-less (energy-scavenging) systems, power dissipation is a critical parameter. As a result, there is a growing demand for reducing the power (energy) consumption in ICs to extremely low levels, not achievable by using classical ""subthreshold CMOS"" techniques. This book introduces a new family of ""subthreshold circuits"" called ""source-coupled circuits"". This family of circuits can be used for implementing digita

New-generation low-power radiation survey instruments

International Nuclear Information System (INIS)

Waechter, D.A.; Bjarke, G.O.; Wolf, M.A.; Trujillo, F.; Umbarger, C.J.

1983-01-01

A number of new, ultra-low-powered radiation instruments have recently been developed at Los Alamos. Among these are two instruments which use a novel power source to eliminate costly batteries. The newly developed gamma detecting radiac, nicknamed the Firefly, and the alpha particle detecting instrument, called the Simple Cordless Alpha Monitor, both use recent advances in miniaturization and power-saving electronics to yield devices which are small, rugged, and very power-frugal. The two instruments consume so little power that the need for batteries to run them is eliminated. They are, instead, powered by a charged capacitor which will operate the instruments for an hour or more. Both line power and mechanical sources are used to charge the storage capacitors which power the instruments

Wake-up receiver based ultra-low-power WBAN

CERN Document Server

Lont, Maarten; Roermund, Arthur van

2014-01-01

This book presents the cross-layer design and optimization of wake-up receivers for wireless body area networks (WBAN), with an emphasis on low-power circuit design. This includes the analysis of medium access control (MAC) protocols, mixer-first receiver design, and implications of receiver impairments on wideband frequency-shift-keying (FSK) receivers. Readers will learn how the overall power consumption is reduced by exploiting the characteristics of body area networks. Theoretical models presented are validated with two different receiver implementations, in 90nm and 40nm CMOS technology.   • Provides an overview of wireless body area network design from the network layer to the circuit implementation, and an overview of the cross-layer design trade-offs; • Discusses design at both the network or MAC-layer and circuit-level, with an emphasis on circuit design; • Covers the design of low-power frequency shift keying (FSK) wake-up-receivers; • Validates theory presented with two different recei...

Adaptive Reactive Power Control of PV Power Plants for Improved Power Transfer Capability under Ultra-Weak Grid Conditions

DEFF Research Database (Denmark)

Yang, Dongsheng; Wang, Xiongfei; Liu, Fangcheng

2018-01-01

with the unity power factor. Then, considering the reactive power compensation from PV inverters, the minimum SCR in respect to Power Factor (PF) is derived, and the optimized coordination of the active and reactive power is exploited. It is revealed that the power transfer capability of PV power plant under...... of a 200 MW PV power plant demonstrate that the proposed method can ensure the rated power transfer of PV power plant with the SCR of 1.25, provided that the PV inverters are operated with the minimal PF=0.9.......This paper analyzes the power transfer limitation of the PV power plant under the ultra-weak grid condition, i.e., when the Short-Circuit Ratio (SCR) is close to 1. It explicitly identifies that a minimum SCR of 2 is required for the PV power plant to deliver the rated active power when operating...

Advanced Power Ultra-Uprates of Existing Plants (APPU) Final Scientific/Technical Report

Energy Technology Data Exchange (ETDEWEB)

Rubiolo, Pablo R. [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Science and Technology Dept.; Conway, Lawarence E. [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Science and Technology Dept.; Oriani, Luca [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Science and Technology Dept.; Lahoda, Edward J. [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Science and Technology Dept.; DeSilva, Greg [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Science and Technology Dept.; Hu, Min H. [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Nuclear Services Division; Hartz, Josh [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Nuclear Services Division; Bachrach, Uriel [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Nuclear Services Division; Smith, Larry [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Nuclear Services Division; Dudek, Daniel F. [Westinghouse Electric Company LLC, Pittsburgh, PA (United States). Nuclear Services Division; Toman, Gary J. [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Feng, Dandong [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Hejzlar, Pavel [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Kazimi, Mujid S. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

2006-03-31

This project assessed the feasibility of a Power Ultra-Uprate on an existing nuclear plant. The study determined the technical and design limitations of the current components, both inside and outside the containment. Based on the identified plant bottlenecks, the design changes for major pieces of equipment required to meet the Power Ultra-Uprate throughput were determined. Costs for modified pieces of equipment and for change-out and disposal of the replaced equipment were evaluated. These costs were then used to develop capital, fuel and operating and maintenance cost estimates for the Power Ultra-Uprate plant. The cost evaluation indicates that the largest cost components are the replacement of power (during the outage required for the uprate) and the new fuel loading. Based on these results, the study concluded that, for a standard 4-loop plant, the proposed Power Ultra-Uprate is technically feasible. However, the power uprate is likely to be more expensive than the cost (per Kw electric installed) of a new plant when large capacity uprates are considered (>25%). Nevertheless, the concept of the Power Ultra-Uprate may be an attractive option for specific nuclear power plants where a large margin exists in the steam and power conversion system or where medium power increases (~600 MWe) are needed. The results of the study suggest that development efforts on fuel technologies for current nuclear power plants should be oriented towards improving the fuel performance (fretting-wear, corrosion, uranium load, manufacturing, safety) required to achieve higher burnup rather focusing on potential increases in the fuel thermal output.

Advanced Power Ultra-Uprates of Existing Plants (APPU) Final Scientific/Technical Report

International Nuclear Information System (INIS)

Rubiolo, Pablo R.; Conway, Lawarence E.; Oriani, Luca; Lahoda, Edward J.; DeSilva, Greg; Hu, Min H.; Hartz, Josh; Bachrach, Uriel; Smith, Larry; Dudek, Daniel F.; Toman, Gary J.; Feng, Dandong; Hejzlar, Pavel; Kazimi, Mujid S.

2006-01-01

This project assessed the feasibility of a Power Ultra-Uprate on an existing nuclear plant. The study determined the technical and design limitations of the current components, both inside and outside the containment. Based on the identified plant bottlenecks, the design changes for major pieces of equipment required to meet the Power Ultra-Uprate throughput were determined. Costs for modified pieces of equipment and for change-out and disposal of the replaced equipment were evaluated. These costs were then used to develop capital, fuel and operating and maintenance cost estimates for the Power Ultra-Uprate plant. The cost evaluation indicates that the largest cost components are the replacement of power (during the outage required for the uprate) and the new fuel loading. Based on these results, the study concluded that, for a ''standard'' 4-loop plant, the proposed Power Ultra-Uprate is technically feasible. However, the power uprate is likely to be more expensive than the cost (per Kw electric installed) of a new plant when large capacity uprates are considered (>25%). Nevertheless, the concept of the Power Ultra-Uprate may be an attractive option for specific nuclear power plants where a large margin exists in the steam and power conversion system or where medium power increases (∼600 MWe) are needed. The results of the study suggest that development efforts on fuel technologies for current nuclear power plants should be oriented towards improving the fuel performance (fretting-wear, corrosion, uranium load, manufacturing, safety) required to achieve higher burnup rather focusing on potential increases in the fuel thermal output

Development of ultra supercritical (USC) power plant

Energy Technology Data Exchange (ETDEWEB)

Chang, Sung Ho; Kim, Bum Soo [KEPCO Research Institute, Daejeon (Korea, Republic of); Min, Taek Ki [Chung Nat' l Univ., Cheongwon (Korea, Republic of)

2012-02-15

For environmental reasons and because of our limited energy resources, high efficiency power generation technology will be necessary in the future. Ultra supercritical (USC) power generation technology is the key to managing the greenhouse gas problems and energy resource problems discussed in the Kyoto Protocol to the United Nations Framework Convention on Climate Change. Other countries and manufacturers are trying to build commercial power plants. In this paper, an efficient method of achieving near zero emission operation of a high efficiency fossil power plant using USC power generation is discussed. Development of USC power generation in Korea has been supported by the Korean government in two phases: Phase I was USC key technology development from 2002 to 2008, and Phase II is USC development and technology optimization from 2010 to 2017.

III-V Ultra-Thin-Body InGaAs/InAs MOSFETs for Low Standby Power Logic Applications

Science.gov (United States)

Huang, Cheng-Ying

As device scaling continues to sub-10-nm regime, III-V InGaAs/InAs metal- oxide-semiconductor ?eld-e?ect transistors (MOSFETs) are promising candidates for replacing Si-based MOSFETs for future very-large-scale integration (VLSI) logic applications. III-V InGaAs materials have low electron effective mass and high electron velocity, allowing higher on-state current at lower VDD and reducing the switching power consumption. However, III-V InGaAs materials have a narrower band gap and higher permittivity, leading to large band-to-band tunneling (BTBT) leakage or gate-induced drain leakage (GIDL) at the drain end of the channel, and large subthreshold leakage due to worse electrostatic integrity. To utilize III-V MOSFETs in future logic circuits, III-V MOSFETs must have high on-state performance over Si MOSFETs as well as very low leakage current and low standby power consumption. In this dissertation, we will report InGaAs/InAs ultra-thin-body MOSFETs. Three techniques for reducing the leakage currents in InGaAs/InAs MOSFETs are reported as described below. 1) Wide band-gap barriers: We developed AlAs0.44Sb0.56 barriers lattice-match to InP by molecular beam epitaxy (MBE), and studied the electron transport in In0.53Ga0.47As/AlAs 0.44Sb0.56 heterostructures. The InGaAs channel MOSFETs using AlAs0.44Sb0.56 bottom barriers or p-doped In0.52 Al0.48As barriers were demonstrated, showing significant suppression on the back barrier leakage. 2) Ultra-thin channels: We investigated the electron transport in InGaAs and InAs ultra-thin quantum wells and ultra-thin body MOSFETs (t ch ~ 2-4 nm). For high performance logic, InAs channels enable higher on-state current, while for low power logic, InGaAs channels allow lower BTBT leakage current. 3) Source/Drain engineering: We developed raised InGaAs and recessed InP source/drain spacers. The raised InGaAs source/drain spacers improve electrostatics, reducing subthreshold leakage, and smooth the electric field near drain, reducing

New generation low power radiation survey instruments

International Nuclear Information System (INIS)

Waechter, D.A.; Bjarke, G.O.; Trujillo, F.; Umbarger, C.J.; Wolf, M.A.

1984-01-01

A number of new, ultra-low-powered radiation instruments have recently been developed at Los Alamos. Among these are two instruments which use a novel power source to eliminate costly batteries. The newly developed gamma detecting radiac, nicknamed the Firefly, and the alpha particle detecting instrument, called the Simple Cordless Alpha Monitor, both use recent advances in miniaturization and powersaving electronics to yield devices which are small, rugged, and very power-frugal. The two instruments consume so little power that the need for batteries to run them is eliminated. They are, instead, powered by a charged capacitor which will operate the instruments for an hour or more. Use of a capacitor as a power source eliminates many problems commonly associated with battery-operated instruments, such as having to open the case to change batteries, battery storage life, availability of batteries in the field, and some savings in weight. Both line power and mechanical sources are used to charge the storage capacitors which power the instruments

A Long-Distance RF-Powered Sensor Node with Adaptive Power Management for IoT Applications.

Science.gov (United States)

Pizzotti, Matteo; Perilli, Luca; Del Prete, Massimo; Fabbri, Davide; Canegallo, Roberto; Dini, Michele; Masotti, Diego; Costanzo, Alessandra; Franchi Scarselli, Eleonora; Romani, Aldo

2017-07-28

We present a self-sustained battery-less multi-sensor platform with RF harvesting capability down to -17 dBm and implementing a standard DASH7 wireless communication interface. The node operates at distances up to 17 m from a 2 W UHF carrier. RF power transfer allows operation when common energy scavenging sources (e.g., sun, heat, etc.) are not available, while the DASH7 communication protocol makes it fully compatible with a standard IoT infrastructure. An optimized energy-harvesting module has been designed, including a rectifying antenna (rectenna) and an integrated nano-power DC/DC converter performing maximum-power-point-tracking (MPPT). A nonlinear/electromagnetic co-design procedure is adopted to design the rectenna, which is optimized to operate at ultra-low power levels. An ultra-low power microcontroller controls on-board sensors and wireless protocol, to adapt the power consumption to the available detected power by changing wake-up policies. As a result, adaptive behavior can be observed in the designed platform, to the extent that the transmission data rate is dynamically determined by RF power. Among the novel features of the system, we highlight the use of nano-power energy harvesting, the implementation of specific hardware/software wake-up policies, optimized algorithms for best sampling rate implementation, and adaptive behavior by the node based on the power received.

A Long-Distance RF-Powered Sensor Node with Adaptive Power Management for IoT Applications

Directory of Open Access Journals (Sweden)

Matteo Pizzotti

2017-07-01

Full Text Available We present a self-sustained battery-less multi-sensor platform with RF harvesting capability down to −17 dBm and implementing a standard DASH7 wireless communication interface. The node operates at distances up to 17 m from a 2 W UHF carrier. RF power transfer allows operation when common energy scavenging sources (e.g., sun, heat, etc. are not available, while the DASH7 communication protocol makes it fully compatible with a standard IoT infrastructure. An optimized energy-harvesting module has been designed, including a rectifying antenna (rectenna and an integrated nano-power DC/DC converter performing maximum-power-point-tracking (MPPT. A nonlinear/electromagnetic co-design procedure is adopted to design the rectenna, which is optimized to operate at ultra-low power levels. An ultra-low power microcontroller controls on-board sensors and wireless protocol, to adapt the power consumption to the available detected power by changing wake-up policies. As a result, adaptive behavior can be observed in the designed platform, to the extent that the transmission data rate is dynamically determined by RF power. Among the novel features of the system, we highlight the use of nano-power energy harvesting, the implementation of specific hardware/software wake-up policies, optimized algorithms for best sampling rate implementation, and adaptive behavior by the node based on the power received.

Development of high sensitivity transimpedance amplifier module for self powered neutron detectors

International Nuclear Information System (INIS)

Khan, T.K.; Tamboli, P.K.; Antony, J.; Balasubramanian, R.; Agilandaeswari, K.; Pramanik, M.

2010-01-01

This paper describes design and development of a Transimpedance Amplifier for amplification of very low current from in core Self Powered Neutron Detectors (SPND). Measurement of neutron flux is very important for operation, control and protection of Nuclear Power Plant (NPP). SPND is used to measure Reactor incore flux/power. Based on sensitivity of emitter material used in SPND, pitch length and neutron flux (power level); the current output from SPND varies from few pA to few μA. The described amplifier is suitable to use for this current range. The amplifier provides a very high gain using a resistive T network feedback topology. The amplifier is designed in two stages using ultra low bias current FET OPAMPs. Design of Transimpedance amplifier is carefully done to include ultra low input bias current, low offset voltage and noise. The amplifier has in built test facility for calibration and on line test facility for measurement of insulation resistance (IR). The amplifier module has on board isolated DC-DC converter circuit complying MIL/STD/461C/D which generate isolated +/-15V and +12V supply to provide parameter to parameter ground isolation and independence among each module/signal.The output from the amplifier is 0V to 6V for 0 to 150%FP. The design is simulated in computer and amplifier used at TAPS-3 was modified as per new design and has been tested at TAPS-3 site. The amplifier performed satisfactorily. The results showed that the IR measurement technique adopted in the design can tolerate lower IR of SPND in existing design. (author)

Ultra Low-Power Acoustic Detector Applicable in Ambient Assistance Living Systems

Directory of Open Access Journals (Sweden)

Iliev I.

2009-12-01

Full Text Available Ambient Assisted Living (AAL includes methods, concepts, systems, devices as well as services, which provide unobtrusive support for daily life based on the context and situation of the assisted person. The technologies applied for AAL are user-centric, i.e. oriented towards the needs and capabilities of the particular user. They are also integrated into the immediate personal environment of the user. As a consequence, the technology is adapting to the user rather than the other way around. The in-house monitoring of elderly or disabled people (hard of hearing, deaf, with limited movement ability, using intelligent sensors is a very desirable service that may potentially increase the user's autonomy and independence while minimizing the risks of living alone. The described ultra low-power acoustic detector allows upgrade of the presented warning systems. It features long-term autonomy and possibility to use it as an element of the wireless personal area network (WPAN.

Experimental verification of a novel MEMS multi-modal vibration energy harvester for ultra-low power remote sensing nodes

Science.gov (United States)

Iannacci, J.; Sordo, G.; Serra, E.; Kucera, M.; Schmid, U.

2015-05-01

In this work, we discuss the verification and preliminary experimental characterization of a MEMS-based vibration Energy Harvester (EH) design. The device, named Four-Leaf Clover (FLC), is based on a circular-shaped mechanical resonator with four petal-like mass-spring cascaded systems. This solution introduces several mechanical Degrees of Freedom (DOFs), and therefore enables multiple resonant modes and deformation shapes in the vibrations frequency range of interest. The target is to realize a wideband multi-modal EH-MEMS device, that overcomes the typical narrowband working characteristics of standard cantilevered EHs, by ensuring flexible and adaptable power source to ultra-low power electronics for integrated remote sensing nodes (e.g. Wireless Sensor Networks - WSNs) in the Internet of Things (IoT) scenario, aiming to self-powered and energy autonomous smart systems. Finite Element Method simulations of the FLC EH-MEMS show the presence of several resonant modes for vibrations up to 4-5 kHz, and level of converted power up to a few μW at resonance and in closed-loop conditions (i.e. with resistive load). On the other hand, the first experimental tests of FLC fabricated samples, conducted with a Laser Doppler Vibrometer (LDV), proved the presence of several resonant modes, and allowed to validate the accuracy of the FEM modeling method. Such a good accordance holds validity for what concerns the coupled field behavior of the FLC EH-MEMS, as well. Both measurements and simulations performed at 190 Hz (i.e. out of resonance) showed the generation of power in the range of nW (Root Mean Square - RMS values). Further steps of this work will include the experimental characterization in a full range of vibrations, aiming to prove the whole functionality of the FLC EH-MEMS proposed design concept.

Power affects performance when the pressure is on: evidence for low-power threat and high-power lift.

Science.gov (United States)

Kang, Sonia K; Galinsky, Adam D; Kray, Laura J; Shirako, Aiwa

2015-05-01

The current research examines how power affects performance in pressure-filled contexts. We present low-power-threat and high-power-lift effects, whereby performance in high-stakes situations suffers or is enhanced depending on one's power; that is, the power inherent to a situational role can produce effects similar to stereotype threat and lift. Three negotiations experiments demonstrate that role-based power affects outcomes but only when the negotiation is diagnostic of ability and, therefore, pressure-filled. We link these outcomes conceptually to threat and lift effects by showing that (a) role power affects performance more strongly when the negotiation is diagnostic of ability and (b) underperformance disappears when the low-power negotiator has an opportunity to self-affirm. These results suggest that stereotype threat and lift effects may represent a more general phenomenon: When the stakes are raised high, relative power can act as either a toxic brew (stereotype/low-power threat) or a beneficial elixir (stereotype/high-power lift) for performance. © 2015 by the Society for Personality and Social Psychology, Inc.

Self-powered integrated systems-on-chip (energy chip)

KAUST Repository

Hussain, Muhammad Mustafa

2010-04-23

In today\\'s world, consumer driven technology wants more portable electronic gadgets to be developed, and the next big thing in line is self-powered handheld devices. Therefore to reduce the power consumption as well as to supply sufficient power to run those devices, several critical technical challenges need to be overcome: a. Nanofabrication of macro/micro systems which incorporates the direct benefit of light weight (thus portability), low power consumption, faster response, higher sensitivity and batch production (low cost). b. Integration of advanced nano-materials to meet the performance/cost benefit trend. Nano-materials may offer new functionalities that were previously underutilized in the macro/micro dimension. c. Energy efficiency to reduce power consumption and to supply enough power to meet that low power demand. We present a pragmatic perspective on a self-powered integrated System on Chip (SoC). We envision the integrated device will have two objectives: low power consumption/dissipation and on-chip power generation for implementation into handheld or remote technologies for defense, space, harsh environments and medical applications. This paper provides insight on materials choices, intelligent circuit design, and CMOS compatible integration.

Self-powered integrated systems-on-chip (energy chip)

Science.gov (United States)

Hussain, M. M.; Fahad, H.; Rojas, J.; Hasan, M.; Talukdar, A.; Oommen, J.; Mink, J.

2010-04-01

In today's world, consumer driven technology wants more portable electronic gadgets to be developed, and the next big thing in line is self-powered handheld devices. Therefore to reduce the power consumption as well as to supply sufficient power to run those devices, several critical technical challenges need to be overcome: a. Nanofabrication of macro/micro systems which incorporates the direct benefit of light weight (thus portability), low power consumption, faster response, higher sensitivity and batch production (low cost). b. Integration of advanced nano-materials to meet the performance/cost benefit trend. Nano-materials may offer new functionalities that were previously underutilized in the macro/micro dimension. c. Energy efficiency to reduce power consumption and to supply enough power to meet that low power demand. We present a pragmatic perspective on a self-powered integrated System on Chip (SoC). We envision the integrated device will have two objectives: low power consumption/dissipation and on-chip power generation for implementation into handheld or remote technologies for defense, space, harsh environments and medical applications. This paper provides insight on materials choices, intelligent circuit design, and CMOS compatible integration.

Self-powered detectors for power reactors: an overview

International Nuclear Information System (INIS)

Ma, J.

2006-01-01

In this paper, Self-Powered Detectors (SPDs) for applications in nuclear power reactors have been reviewed. Based on their responses to radiation, these detectors can be divided into delayed response Self-Powered Neutron Detector (SPND), prompt response SPND and Self-Powered Gamma Detector (SPGD). The operational principles of these detectors are presented and their distinctive characteristics are examined accordingly. The analytical models and Monte Carlo method to calculate the responses of these detectors to neutron flux and external gamma rays are reviewed. The paper has also considered some related signal processing techniques, such as detector calibrations and detector signal compensations. Furthermore, a couple of failure modes have also been analyzed. Finally, applications of SPD in nuclear power reactors are summarized. (author)

Self-powered detectors for power reactors: an overview

Energy Technology Data Exchange (ETDEWEB)

Ma, J. [Univ. of Western Ontario, Dept. of Mechanical and Materials Engineering, London, Ontario (Canada)]. E-mail: jma64@uwo.ca

2006-07-01

In this paper, Self-Powered Detectors (SPDs) for applications in nuclear power reactors have been reviewed. Based on their responses to radiation, these detectors can be divided into delayed response Self-Powered Neutron Detector (SPND), prompt response SPND and Self-Powered Gamma Detector (SPGD). The operational principles of these detectors are presented and their distinctive characteristics are examined accordingly. The analytical models and Monte Carlo method to calculate the responses of these detectors to neutron flux and external gamma rays are reviewed. The paper has also considered some related signal processing techniques, such as detector calibrations and detector signal compensations. Furthermore, a couple of failure modes have also been analyzed. Finally, applications of SPD in nuclear power reactors are summarized. (author)

Ultra-Low Power Consuming Direct Radiation Sensors Based on Floating Gate Structures

Directory of Open Access Journals (Sweden)

Evgeny Pikhay

2017-07-01

Full Text Available In this paper, we report on ultra-low power consuming single poly floating gate direct radiation sensors. The developed devices are intended for total ionizing dose (TID measurements and fabricated in a standard CMOS process flow. Sensor design and operation is discussed in detail. Original array sensors were suggested and fabricated that allowed high statistical significance of the radiation measurements and radiation imaging functions. Single sensors and array sensors were analyzed in combination with the specially developed test structures. This allowed insight into the physics of sensor operations and exclusion of the phenomena related to material degradation under irradiation in the interpretation of the measurement results. Response of the developed sensors to various sources of ionizing radiation (Gamma, X-ray, UV, energetic ions was investigated. The optimal design of sensor for implementation in dosimetry systems was suggested. The roadmap for future improvement of sensor performance is suggested.

Threshold self-powered gamma detector for use as a nuclear reactor power monitor

International Nuclear Information System (INIS)

LeVert, F.E.

1977-01-01

A study of a threshold self-powered gamma detector for use as a nuclear reactor power monitor was conducted. Measurements were performed to ascertain whether certain detector material arrangements could be used to obtain significant discrimination against low energy gammas. Results indicating agreement between detector response and reactor power output are presented. Evidence of rejection of low energy gammas by the detector is presented. The simplicity of construction and ruggedness of the detector are also discussed

Low-power operation using self-timed circuits and adaptive scaling of the supply voltage

DEFF Research Database (Denmark)

Nielsen, Lars Skovby; Niessen, C.; Sparsø, Jens

1994-01-01

Recent research has demonstrated that for certain types of applications like sampled audio systems, self-timed circuits can achieve very low power consumption, because unused circuit parts automatically turn into a stand-by mode. Additional savings may be obtained by combining the self......-timed circuits with a mechanism that adaptively adjusts the supply voltage to the smallest possible, while maintaining the performance requirements. This paper describes such a mechanism, analyzes the possible power savings, and presents a demonstrator chip that has been fabricated and tested. The idea...... of voltage scaling has been used previously in synchronous circuits, and the contributions of the present paper are: 1) the combination of supply scaling and self-timed circuitry which has some unique advantages, and 2) the thorough analysis of the power savings that are possible using this technique.>...

Towards self-sustainable power systems

DEFF Research Database (Denmark)

Angjelichinoski, Marko; Danzi, Pietro; Stefanovic, Cedomir

2017-01-01

We propose use of a “modemless” communication solution, termed power talk, tailored for optimization and monitoring, i.e., upper layer control in low voltage DC MicroGrids (MGs). Specifically, the exchange of the information required for the upper control among control agents is achieved by modul......We propose use of a “modemless” communication solution, termed power talk, tailored for optimization and monitoring, i.e., upper layer control in low voltage DC MicroGrids (MGs). Specifically, the exchange of the information required for the upper control among control agents is achieved...... of minimizing the cost of the generation. The simulation results prove the feasibility of power talk as enabler of fully self-sustainable DC MicroGrids....

Characteristics of self-powered neutron detectors used in power reactors

International Nuclear Information System (INIS)

Todt, W.H.

1997-01-01

Self-Powered Neutron Detectors have been used effectively as in-core flux monitors for over twenty-five years in nuclear power reactors world-wide. The basic properties of these radiation sensors are described including their nuclear, electrical and mechanical characteristics. Recommendations are given for the proper choice of the self-powered detector emitter to provide the proper response time and radiation sensitivity desired for use in an effective in-core radiation monitoring system. Examples are shown of specific self-powered detector designs which are being effectively used in in-core instrumentation systems for pressurised water, heavy water and graphite moderated light water reactors. Examples are also shown of the mechanical configurations of in-core assemblies of self-powered detectors combined with in-core thermocouples presently used in pressurised water and heavy water reactors worldwide. This paper is a summary of a new IEC standard to be issued in 1996 describing the characteristics and test methods of self-powered detectors used in nuclear power reactors. (author)

Ultra-low power sensor for autonomous non-invasive voltage measurement in IoT solutions for energy efficiency

Science.gov (United States)

Villani, Clemente; Balsamo, Domenico; Brunelli, Davide; Benini, Luca

2015-05-01

Monitoring current and voltage waveforms is fundamental to assess the power consumption of a system and to improve its energy efficiency. In this paper we present a smart meter for power consumption which does not need any electrical contact with the load or its conductors, and which can measure both current and voltage. Power metering becomes easier and safer and it is also self-sustainable because an energy harvesting module based on inductive coupling powers the entire device from the output of the current sensor. A low cost 32-bit wireless CPU architecture is used for data filtering and processing, while a wireless transceiver sends data via the IEEE 802.15.4 standard. We describe in detail the innovative contact-less voltage measurement system, which is based on capacitive coupling and on an algorithm that exploits two pre-processing channels. The system self-calibrates to perform precise measurements regardless the cable type. Experimental results demonstrate accuracy in comparison with commercial high-cost instruments, showing negligible deviations.

Self-Powered WSN for Distributed Data Center Monitoring

Directory of Open Access Journals (Sweden)

Davide Brunelli

2016-01-01

Full Text Available Monitoring environmental parameters in data centers is gathering nowadays increasing attention from industry, due to the need of high energy efficiency of cloud services. We present the design and the characterization of an energy neutral embedded wireless system, prototyped to monitor perpetually environmental parameters in servers and racks. It is powered by an energy harvesting module based on Thermoelectric Generators, which converts the heat dissipation from the servers. Starting from the empirical characterization of the energy harvester, we present a power conditioning circuit optimized for the specific application. The whole system has been enhanced with several sensors. An ultra-low-power micro-controller stacked over the energy harvesting provides an efficient power management. Performance have been assessed and compared with the analytical model for validation.

Design of a 300-Watt Isolated Power Supply for Ultra-Fast Tracking Converters

DEFF Research Database (Denmark)

Nguyen-Duy, Khiem; Ouyang, Ziwei; Petersen, Lars Press

2015-01-01

This paper presents the design of a medium-powerrating isolated power supply for ultra-fast tracking converters and MOS-gate driver circuits in medium and high voltage applications. The key feature of the design is its very low circuit input-to-output parasitic capacitance, which maximizes its...

Ultra-capacitors in power conversion systems analysis, modeling and design in theory and practice

CERN Document Server

Grbovic, Petar J

2014-01-01

Divided into five parts, this book is focused on ultra-capacitors and their applications in power conversion systems. It discusses ultra-capacitor analysis, modelling and module design from a macroscopic (application) perspective. It also describes power conversion applications, interface dc-dc converter design and entire conversion system design. Part One covers the background of energy storage technologies, with particular attention on state-of-the-art ultra-capacitor energy storage technologies. In Chapter four of this part, power conversion systems with integrated energy storage is discus

Low-Power Built-In Self-Test Techniques for Embedded SRAMs

Directory of Open Access Journals (Sweden)

Shyue-Kung Lu

2007-01-01

Full Text Available The severity of power consumption during parallel BIST of embedded memory cores is growing significantly. In order to alleviate this problem, a row bank-based precharge technique based on the divided wordline (DWL architecture is proposed for low-power testing of embedded SRAMs. The memory cell array is first divided into row banks. The effectiveness of the row bank-based precharge technique is due to the predictable address sequence during test. In low-power test mode, instead of precharging the entire memory array, only the current accessed row bank is precharged. This will result in significant power saving for the precharge circuitry. The precharge power can be reduced to 1/b of that of the traditional precharge techniques, where b denotes the number of row banks in the memory array. With simple transmission gates and inverters, the modified precharge control circuitry was also designed. The hardware overhead for implementing the low-power technique is almost negligible. Moreover, the corresponding BIST design to implement the low-power technique is almost the same as the conventional BIST designs. It is also notable that the inherent low-power characteristics of the DWL architecture can be preserved. According to experimental results, 48.9% power reduction can be achieved for a 256 × 256 bit-oriented SRAM. The memory is divided into 8 row banks. Moreover, if the number of row banks increases, the power saving will also increase.

Design of Low Inductance Switching Power Cell for GaN HEMT Based Inverter

Energy Technology Data Exchange (ETDEWEB)

Gurpinar, Emre [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Power Electronics and Electric Machinery Research Group; Iannuzzo, Francesco [Aalborg Univ., Aalborg (Denmark). Dept. of Energy Technology; Yang, Yongheng [Aalborg Univ., Aalborg (Denmark). Dept. of Energy Technology; Castellazzi, Alberto [Univ. of Nottingham (United Kingdom). Power Electronics, Machines and Control (PEMC); Blaabjerg, Frede [Aalborg Univ., Aalborg (Denmark). Dept. of Energy Technology

2017-11-23

Here in this paper, an ultra-low inductance power cell is designed for a three-Level Active Neutral Point Clamped (3LANPC) based on 650 V gallium nitride (GaN) HEMT devices. The 3L-ANPC topology with GaN HEMT devices and the selected modulation scheme suitable for wide-bandgap (WBG) devices are presented. The commutation loops, which mainly contribute to voltage overshoots and increase of switching losses, are discussed. The ultra-low inductance power cell design based on a fourlayer Printed Circuit Board (PCB) with the aim to maximize the switching performance of GaN HEMTs is explained. The design of gate drivers for the GaN HEMT devices is presented. Parasitic inductance and resistance of the proposed design are extracted with finite element analysis and discussed. Common mode behaviours based on the SPICE model of the converter are analyzed. Experimental results on the designed 3L-ANPC with the output power of up to 1 kW are presented, which verifies the performance of the proposed design in terms of ultra-low inductance.

Design of Low Inductance Switching Power Cell for GaN HEMT Based Inverter

International Nuclear Information System (INIS)

Gurpinar, Emre; Iannuzzo, Francesco; Yang, Yongheng; Castellazzi, Alberto; Blaabjerg, Frede

2017-01-01

Here in this paper, an ultra-low inductance power cell is designed for a three-Level Active Neutral Point Clamped (3LANPC) based on 650 V gallium nitride (GaN) HEMT devices. The 3L-ANPC topology with GaN HEMT devices and the selected modulation scheme suitable for wide-bandgap (WBG) devices are presented. The commutation loops, which mainly contribute to voltage overshoots and increase of switching losses, are discussed. The ultra-low inductance power cell design based on a fourlayer Printed Circuit Board (PCB) with the aim to maximize the switching performance of GaN HEMTs is explained. The design of gate drivers for the GaN HEMT devices is presented. Parasitic inductance and resistance of the proposed design are extracted with finite element analysis and discussed. Common mode behaviours based on the SPICE model of the converter are analyzed. Experimental results on the designed 3L-ANPC with the output power of up to 1 kW are presented, which verifies the performance of the proposed design in terms of ultra-low inductance.

Technology breakthroughs in high performance metal-oxide-semiconductor devices for ultra-high density, low power non-volatile memory applications

Science.gov (United States)

Hong, Augustin Jinwoo

Non-volatile memory devices have attracted much attention because data can be retained without power consumption more than a decade. Therefore, non-volatile memory devices are essential to mobile electronic applications. Among state of the art non-volatile memory devices, NAND flash memory has earned the highest attention because of its ultra-high scalability and therefore its ultra-high storage capacity. However, human desire as well as market competition requires not only larger storage capacity but also lower power consumption for longer battery life time. One way to meet this human desire and extend the benefits of NAND flash memory is finding out new materials for storage layer inside the flash memory, which is called floating gate in the state of the art flash memory device. In this dissertation, we study new materials for the floating gate that can lower down the power consumption and increase the storage capacity at the same time. To this end, we employ various materials such as metal nanodot, metal thin film and graphene incorporating complementary-metal-oxide-semiconductor (CMOS) compatible processes. Experimental results show excellent memory effects at relatively low operating voltages. Detailed physics and analysis on experimental results are discussed. These new materials for data storage can be promising candidates for future non-volatile memory application beyond the state of the art flash technologies.

A smart mobile pouch as a biomechanical energy harvester towards self-powered smart wireless power transfer applications.

Science.gov (United States)

Chandrasekhar, Arunkumar; Alluri, Nagamalleswara Rao; Sudhakaran, M S P; Mok, Young Sun; Kim, Sang-Jae

2017-07-20

A Smart Mobile Pouch Triboelectric Nanogenerator (SMP-TENG) is introduced as a promising eco-friendly approach for scavenging biomechanical energy for powering next generation intelligent devices and smart phones. This is a cost-effective and robust method for harvesting energy from human motion, by utilizing worn fabrics as a contact material. The SMP-TENG is capable of harvesting energy in two operational modes: lateral sliding and vertical contact and separation. Moreover, the SMP-TENG can also act as a self-powered emergency flashlight and self-powered pedometer during normal human motion. A wireless power transmission setup integrated with SMP-TENG is demonstrated. This upgrades the traditional energy harvesting device into a self-powered wireless power transfer SMP-TENG. The wirelessly transferred power can be used to charge a Li-ion battery and light LEDs. The SMP-TENG opens a wide range of opportunities in the field of self-powered devices and low maintenance energy harvesting systems for portable and wearable electronic gadgets.

When Power Shapes Interpersonal Behavior: Low Relationship Power Predicts Men’s Aggressive Responses to Low Situational Power

Science.gov (United States)

Overall, Nickola C.; Hammond, Matthew D.; McNulty, James K.; Finkel, Eli J.

2016-01-01

When does power in intimate relationships shape important interpersonal behaviors, such as psychological aggression? Five studies tested whether possessing low relationship power was associated with aggressive responses, but (1) only within power-relevant relationship interactions when situational power was low, and (2) only by men because masculinity (but not femininity) involves the possession and demonstration of power. In Studies 1 and 2, men lower in relationship power exhibited greater aggressive communication during couples’ observed conflict discussions, but only when they experienced low situational power because they were unable to influence their partner. In Study 3, men lower in relationship power reported greater daily aggressive responses toward their partner, but only on days when they experienced low situational power because they were either (a) unable to influence their partner or (b) dependent on their partner for support. In Study 4, men who possessed lower relationship power exhibited greater aggressive responses during couples’ support-relevant discussions, but only when they had low situational power because they needed high levels of support. Study 5 provided evidence for the theoretical mechanism underlying men’s aggressive responses to low relationship power. Men who possessed lower relationship power felt less manly on days they faced low situational power because their partner was unwilling to change to resolve relationship problems, which in turn predicted greater aggressive responses to their partner. These results demonstrate that fully understanding when and why power is associated with interpersonal behavior requires differentiating between relationship and situational power. PMID:27442766

Self-Powered Functional Device Using On-Chip Power Generation

KAUST Repository

Hussain, Muhammad Mustafa

2012-01-26

An apparatus, system, and method for a self-powered device using on-chip power generation. In some embodiments, the apparatus includes a substrate, a power generation module on the substrate, and a power storage module on the substrate. The power generation module may include a thermoelectric generator made of bismuth telluride.

Self-Powered Functional Device Using On-Chip Power Generation

KAUST Repository

Hussain, Muhammad Mustafa

2012-01-01

An apparatus, system, and method for a self-powered device using on-chip power generation. In some embodiments, the apparatus includes a substrate, a power generation module on the substrate, and a power storage module on the substrate. The power generation module may include a thermoelectric generator made of bismuth telluride.

Ultra-Low-Power Analog-to-Digital Converters for Medical Applications

OpenAIRE

Zhang, Dai

2014-01-01

Biomedical systems are commonly attached to or implanted into human bodies, and powered by harvested energy or small batteries. In these systems, analog-to-digital converters (ADCs) are key components as the interface between the analog world and the digital domain. Conversion of the low frequency bioelectric signals does not require high speed, but ultralow- power operation. This combined with the required conversion accuracy makes the design of such ADCs a major challenge. Among prevalent A...

When dispositional and role power fit: implications for self-expression and self-other congruence.

Science.gov (United States)

Chen, Serena; Langner, Carrie A; Mendoza-Denton, Rodolfo

2009-03-01

Integrating and extending the literatures on social power and person-environment fit, 4 studies tested the hypothesis that when people's dispositional beliefs about their capacity to influence others fit their assigned role power, they are more likely to engage in self-expression-that is, behave in line with their states and traits-thereby increasing their likelihood of being perceived by others in a manner congruent with their own self-judgments (i.e., self-other congruence). In Studies 1-3, dispositionally high- and low-power participants were randomly assigned to play a high- or low-power role in an interaction with a confederate. When participants' dispositional and role power fit (vs. conflicted), they reported greater self-expression (Study 1). Furthermore, under dispositional-role power fit conditions, the confederate's ratings of participants' emotional experiences (Study 2) and personality traits (Study 3) were more congruent with participants' self-reported emotions and traits. Study 4's results replicated Study 3's results using an implicit manipulation of power and outside observers' (rather than a confederate's) ratings of participants. Implications for research on power and person perception are discussed.

Characteristics of self-powered neutron detectors used in power reactors

International Nuclear Information System (INIS)

Todt, William H. Sr.

1998-01-01

Self-powered neutron detectors have been used effectively as in-core flux monitors for over twenty-five years in nuclear power reactors worldwide. This paper describes the basic properties of these radiation sensors including their nuclear, electrical and mechanical characteristics. Recommendations are given for the proper choice of the self-powered detector emitter to provide the proper response time and radiation sensitivity desired for use in an effective in-core radiation monitoring system. Examples are shown of specific self-powered detector designs, which are being effectively, used in in-core instrumentation systems for pressurized water, heavy water and graphite moderated light water reactors. Also examples are shown of the mechanical configurations of in-core assemblies of self-powered detectors combined with in-core thermocouples presently used in pressurized water and heavy water reactors worldwide. (author)

Thermoelectric self-cooling for power electronics: Increasing the cooling power

International Nuclear Information System (INIS)

Martinez, Alvaro; Astrain, David; Aranguren, Patricia

2016-01-01

Thermoelectric self-cooling was firstly conceived to increase, without electricity consumption, the cooling power of passive cooling systems. This paper studies the combination of heat pipe exchangers and thermoelectric self-cooling, and demonstrates its applicability to the cooling of power electronics. Experimental tests indicate that source-to-ambient thermal resistance reduces by around 30% when thermoelectric self-cooling system is installed, compared to that of the heat pipe exchanger under natural convection. Neither additional electric power nor cooling fluids are required. This thermal resistance reaches 0.346 K/W for a heat flux of 24.1 kW/m"2, being one order of magnitude lower than that obtained in previous designs. In addition, the system adapts to the cooling demand, reducing this thermal resistance for increasing heat. Simulation tests have indicated that simple system modifications allow relevant improvements in the cooling power. Replacement of a thermoelectric module with a thermal bridge leads to 33.54 kW/m"2 of top cooling power. Likewise, thermoelectric modules with shorter legs and higher number of pairs lead to a top cooling power of 44.17 kW/m"2. These results demonstrate the applicability of thermoelectric self-cooling to power electronics. - Highlights: • Cooling power of passive systems increased. • No electric power consumption. • Applicable for the cooling of power electronics. • Up to 44.17 kW/m"2 of cooling power, one order of magnitude higher. • Source-to-ambient thermal resistance reduces by 30%.

Design and implementation of an ultra-low power passive UHF RFID tag

International Nuclear Information System (INIS)

Shen Jinpeng; Wang Xin'an; Liu Shan; Zong Hongqiang; Huang Jinfeng; Yang Xin; Feng Xiaoxing; Ge Binjie

2012-01-01

This paper presents a fully integrated passive UHF RFID tag chip complying with the ISO18000-6B protocol. The tag chip includes an RF/analog front-end, a baseband processor, and a 512-bit EEPROM memory. To improve power conversion efficiency, a Schottky barrier diode based rectifier is adopted. A novel voltage reference using the peaking current source is discussed in detail, which can meet the low-power, low-voltage requirement while retaining circuit simplicity. Most of the analog blocks are designed to work under sub-1 V to reduce power consumption, and several practical methods are used to further reduce the power consumption of the baseband processor. The whole tag chip is implemented in a TSMC 0.18 μm CMOS process with a die size of 800 × 800 μm 2 . Measurement results show that the total power consumption of the tag chip is only 7.4 μW with a sensitivity of −12 dBm. (semiconductor integrated circuits)

Error Immune Logic for Low-Power Probabilistic Computing

Directory of Open Access Journals (Sweden)

Bo Marr

2010-01-01

design for the maximum amount of energy savings per a given error rate. Spice simulation results using a commercially available and well-tested 0.25 μm technology are given verifying the ultra-low power, probabilistic full-adder designs. Further, close to 6X energy savings is achieved for a probabilistic full-adder over the deterministic case.

Wireless powering for low-power distributed sensors

Directory of Open Access Journals (Sweden)

Popović Zoya B.

2006-01-01

Full Text Available In this paper, an overview of the field of wireless powering is presented with an emphasis on low-power applications. Several rectenna elements and arrays are discussed in more detail: (1 a 10-GHz array for powering sensors in aircraft wings; (2 a single antenna in the 2.4-GHz ISM band for low-power assisted-living sensors; and (3 a broadband array for power harvesting in the 2-18GHz frequency range.

Self-oscillating modulators for direct energy conversion audio power amplifiers

DEFF Research Database (Denmark)

Ljusev, Petar; Andersen, Michael Andreas E.

2005-01-01

Direct energy conversion audio power amplifier represents total integration of switching-mode power supply and Class D audio power amplifier into one compact stage, achieving high efficiency, high level of integration, low component count and eventually low cost. This paper presents how self-oscillating...

Low power and self-reconfigurable WBAN controller for continuous bio-signal monitoring system

NARCIS (Netherlands)

Lee, S.; Yoo, H.J.

2013-01-01

The WBAN controller with Branched Bus (BB) topology and Continuous Data Transmission (CDT) protocol with low power consumption and self- reconfigurability is proposed for wearable healthcare applications. The BB topology and CDT protocol is a combination of conventional Bus and Star topology and a

A 3D paper-based enzymatic fuel cell for self-powered, low-cost glucose monitoring.

Science.gov (United States)

Fischer, Christopher; Fraiwan, Arwa; Choi, Seokheun

2016-05-15

In this work, we demonstrate a novel low-cost, self-powered paper-based biosensor for glucose monitoring. The device operating mechanism is based on a glucose/oxygen enzymatic fuel cell using an electrochemical energy conversion as a transducing element for glucose monitoring. The self-powered glucose biosensor features (i) a 3D origami paper-based structure for easy system integration onto paper, (ii) an air-cathode on paper for low-cost production and easy operation, and (iii) a screen printed chitosan/glucose oxidase anode for stable current generation as an analytical signal for glucose monitoring. The sensor showed a linear range of output current at 1-5mM glucose (R(2)=0.996) with a sensitivity of 0.02 µA mM(-1). The advantages offered by such a device, including a low cost, lack of external power sources/sophisticated external transducers, and the capacity to rapidly generate reliable results, are well suited for the clinical and social settings of the developing world. Copyright © 2015 Elsevier B.V. All rights reserved.

Silicon on ferroelectic insulator field effect transistor (SOF-FET) a new device for the next generation ultra low power circuits

Science.gov (United States)

Es-Sakhi, Azzedin D.

Field effect transistors (FETs) are the foundation for all electronic circuits and processors. These devices have progressed massively to touch its final steps in sub-nanometer level. Left and right proposals are coming to rescue this progress. Emerging nano-electronic devices (resonant tunneling devices, single-atom transistors, spin devices, Heterojunction Transistors rapid flux quantum devices, carbon nanotubes, and nanowire devices) took a vast share of current scientific research. Non-Si electronic materials like III-V heterostructure, ferroelectric, carbon nanotubes (CNTs), and other nanowire based designs are in developing stage to become the core technology of non-classical CMOS structures. FinFET present the current feasible commercial nanotechnology. The scalability and low power dissipation of this device allowed for an extension of silicon based devices. High short channel effect (SCE) immunity presents its major advantage. Multi-gate structure comes to light to improve the gate electrostatic over the channel. The new structure shows a higher performance that made it the first candidate to substitute the conventional MOSFET. The device also shows a future scalability to continue Moor's Law. Furthermore, the device is compatible with silicon fabrication process. Moreover, the ultra-low-power (ULP) design required a subthreshold slope lower than the thermionic-emission limit of 60mV/ decade (KT/q). This value was unbreakable by the new structure (SOI-FinFET). On the other hand most of the previews proposals show the ability to go beyond this limit. However, those pre-mentioned schemes have publicized a very complicated physics, design difficulties, and process non-compatibility. The objective of this research is to discuss various emerging nano-devices proposed for ultra-low-power designs and their possibilities to replace the silicon devices as the core technology in the future integrated circuit. This thesis proposes a novel design that exploits the

Low-Power Silicon-based Thermal Sensors and Actuators for Chemical Applications

NARCIS (Netherlands)

Vereshchagina, E.

2011-01-01

In the Hot Silicon project low and ultra-low-power Si-based hot surface devices have been developed, i.e. thermal sensors and actuators, for application in catalytic gas micro sensors, micro- and nano- calorimeters. This work include several scientific and technological aspects: • Design and

Ultra-low power circuits based on tunnel FETs for energy harvesting applications

OpenAIRE

Cavalheiro, David

2017-01-01

There has been a tremendous evolution in integrated circuit technology in the past decades. With the scaling of complementary metal-oxide-semiconductor (CMOS) transistors, faster, less power consuming and more complex chips per unit area have made possible electronic gadgets to evolve to what we see today. The increasing demand in electronic portability imposes low power consumption as a key metric to analog and digital circuit design. While dynamic power consumption decreases quadraticall...

Loss optimizing low power 50 Hz transformers intended for AC/DC standby power supplies

DEFF Research Database (Denmark)

Nielsen, Nils

2004-01-01

This paper presents the measured efficiency on selected low power conventional 50 Hz/230 V-AC transformers. The small transformers are intended for use in 1 W@5 V-DC series- or buck-regulated power supplies for standby purposes. The measured efficiency is compared for cheap off-the-self transformer...

Analysis of Opportunity to Create Self-Regulating Reactor Facility of Extra-Low Power

International Nuclear Information System (INIS)

Kazansky, Y.A.; Levtchenko, V.A.; Yuriev, Y.S.

2002-01-01

This paper deals with fundamental possibilities (economy, safety, self-regulation) of creating an extra-low power reactor facility for heat supply. It contains the results of calculations for thermal and fast neutron reactors. The concept of this type of a reactor had been developed by the contributors earlier

Design of an ultra low power third order continuous time current mode ΣΔ modulator for WLAN applications.

Science.gov (United States)

Behzadi, Kobra; Baghelani, Masoud

2014-05-01

This paper presents a third order continuous time current mode ΣΔ modulator for WLAN 802.11b standard applications. The proposed circuit utilized feedback architecture with scaled and optimized DAC coefficients. At circuit level, we propose a modified cascade current mirror integrator with reduced input impedance which results in more bandwidth and linearity and hence improves the dynamic range. Also, a very fast and precise novel dynamic latch based current comparator is introduced with low power consumption. This ultra fast comparator facilitates increasing the sampling rate toward GHz frequencies. The modulator exhibits dynamic range of more than 60 dB for 20 MHz signal bandwidth and OSR of 10 while consuming only 914 μW from 1.8 V power supply. The FoM of the modulator is calculated from two different methods, and excellent performance is achieved for proposed modulator.

Ultra low power CMOS-based sensor for on-body radiation dose measurements

KAUST Repository

Arsalan, Muhammad

2012-03-01

For the first time, a dosimeter employing two floating gate radiation field effect transistors (FGRADFET) and operating at mere 0.1 V is presented. The novel dosimeter requires no power during irradiation and consumes only 1 μ Wduring readout. Besides the low power operation, structural changes at the device level have enhanced the sensitivity of the dosimeter considerably as compared to previous designs. The dosimeter is integrated with a wireless transmitter chip, thus eliminating all unwanted communication and power cables. It has been realized monolithically in DALSA\\'s 0.8 μ m complementary metal-oxide-semiconductor process and characterized with X-ray and γ-ray sources. A maximum sensitivity of 5 mV/rad for X-rays and 1.1 mV/rad for gamma;-rays have been achieved in measurements. Due to its small size, low-power, and wireless operation, the design is highly suitable for miniaturized, wearable, and battery operated dosimeters intended for radiotherapy and space applications. © 2012 IEEE.

Ultra low power CMOS-based sensor for on-body radiation dose measurements

KAUST Repository

Arsalan, Muhammad; Shamim, Atif; Shams, Maitham; Tarr, Nathan Garry; Roy, Langis

2012-01-01

For the first time, a dosimeter employing two floating gate radiation field effect transistors (FGRADFET) and operating at mere 0.1 V is presented. The novel dosimeter requires no power during irradiation and consumes only 1 μ Wduring readout. Besides the low power operation, structural changes at the device level have enhanced the sensitivity of the dosimeter considerably as compared to previous designs. The dosimeter is integrated with a wireless transmitter chip, thus eliminating all unwanted communication and power cables. It has been realized monolithically in DALSA's 0.8 μ m complementary metal-oxide-semiconductor process and characterized with X-ray and γ-ray sources. A maximum sensitivity of 5 mV/rad for X-rays and 1.1 mV/rad for gamma;-rays have been achieved in measurements. Due to its small size, low-power, and wireless operation, the design is highly suitable for miniaturized, wearable, and battery operated dosimeters intended for radiotherapy and space applications. © 2012 IEEE.

Back End of Line Nanorelays for Ultra-low Power Monolithic Integrated NEMS-CMOS Circuits

KAUST Repository

Lechuga Aranda, Jesus Javier

2016-05-01

Since the introduction of Complementary-Metal-Oxide-Semiconductor (CMOS) technology, the chip industry has enjoyed many benefits of transistor feature size scaling, including higher speed and device density and improved energy efficiency. However, in the recent years, the IC designers have encountered a few roadblocks, namely reaching the physical limits of scaling and also increased device leakage which has resulted in a slow-down of supply voltage and power density scaling. Therefore, there has been an extensive hunt for alternative circuit architectures and switching devices that can alleviate or eliminate the current crisis in the semiconductor industry. The Nano-Electro-Mechanical (NEM) relay is a promising alternative switch that offers zero leakage and abrupt turn-on behaviour. Even though these devices are intrinsically slower than CMOS transistors, new circuit design techniques tailored for the electromechanical properties of such devices can be leveraged to design medium performance, ultra-low power integrated circuits. In this thesis, we deal with a new generation of such devices that is built in the back end of line (BEOL) CMOS process and is an ideal option for full integration with current CMOS transistor technology. Simulation and verification at the circuit and system level is a critical step in the design flow of microelectronic circuits, and this is especially important for new technologies that lack the standard design infrastructure and well-known verification platforms. Although most of the physical and electrical properties of NEM structures can be simulated using standard electronic automation software, there is no report of a reliable behavioural model for NEMS switches that enable large circuit simulations. In this work, we present an optimised model of a BEOL nano relay that encompasses all the electromechanical characteristics of the device and is robust and lightweight enough for VLSI applications that require simulation of thousands of

Beginning Power BI with Excel 2013 self-service business intelligence using Power Pivot, Power View, Power Query, and Power Map

CERN Document Server

Clark, Dan

2014-01-01

Understanding your company's data has never been easier than with Microsoft's new Power BI package for Excel 2013. Consisting of four powerful tools-Power Pivot, Power View, Power Query and Power Maps-Power BI makes self-service business intelligence a reality for a wide range of users, bridging the traditional gap between Excel users, business analysts and IT experts and making it easier for everyone to work together to build the data models that can give you game-changing insights into your business. Beginning Power BI with Excel 2013 guides you step by step through the process of analyzin

A 600-µW ultra-low-power associative processor for image pattern recognition employing magnetic tunnel junction-based nonvolatile memories with autonomic intelligent power-gating scheme

Science.gov (United States)

Ma, Yitao; Miura, Sadahiko; Honjo, Hiroaki; Ikeda, Shoji; Hanyu, Takahiro; Ohno, Hideo; Endoh, Tetsuo

2016-04-01

A novel associative processor using magnetic tunnel junction (MTJ)-based nonvolatile memories has been proposed and fabricated under a 90 nm CMOS/70 nm perpendicular-MTJ (p-MTJ) hybrid process for achieving the exceptionally low-power performance of image pattern recognition. A four-transistor 2-MTJ (4T-2MTJ) spin transfer torque magnetoresistive random access memory was adopted to completely eliminate the standby power. A self-directed intelligent power-gating (IPG) scheme specialized for this associative processor is employed to optimize the operation power by only autonomously activating currently accessed memory cells. The operations of a prototype chip at 20 MHz are demonstrated by measurement. The proposed processor can successfully carry out single texture pattern matching within 6.5 µs using 128-dimension bag-of-feature patterns, and the measured average operation power of the entire processor core is only 600 µW. Compared with the twin chip designed with 6T static random access memory, 91.2% power reductions are achieved. More than 88.0% power reductions are obtained compared with the latest associative memories. The further power performance analysis is discussed in detail, which verifies the special superiority of the proposed processor in power consumption for large-capacity memory-based VLSI systems.

Applications of energy harvesting for ultralow power technology

Science.gov (United States)

Pop-Vadean, A.; Pop, P. P.; Barz, C.; Chiver, O.

2015-06-01

Ultra-low-power (ULP) technology is enabling a wide range of new applications that harvest ambient energy in very small amounts and need little or no maintenance - self-sustaining devices that are capable of perpetual or nearly perpetual operation. These new systems, which are now appearing in industrial and consumer electronics, also promise great changes in medicine and health. Until recently, the idea of micro-scale energy harvesting, and collecting miniscule amounts of ambient energy to power electronic systems, was still limited to research proposals and laboratory experiments.Today an increasing number of systems are appearing that take advantage of light, vibrations and other forms of previously wasted environmental energy for applications where providing line power or maintaining batteries is inconvenient. In the industrial world, where sensors gather information from remote equipment and hazardous processes; in consumer electronics, where mobility and convenience are served; and in medical systems, with unique requirements for prosthetics and non-invasive monitoring, energy harvesting is rapidly expanding into new applications.This paper serves as a survey for applications of energy harvesting for ultra low power technology based on various technical papers available in the public domain.

Resonator-Based Silicon Electro-Optic Modulator with Low Power Consumption

Science.gov (United States)

Xin, Maoqing; Danner, Aaron J.; Eng Png, Ching; Thor Lim, Soon

2009-04-01

This paper demonstrates, via simulation, an electro-optic modulator based on a subwavelength Fabry-Perot resonator cavity with low power consumption of 86 µW/µm. This is, to the best of our knowledge, the lowest power reported for silicon photonic bandgap modulators. The device is modulated at a doped p-i-n junction overlapping the cavity in a silicon waveguide perforated with etched holes, with the doping area optimized for minimum power consumption. The surface area of the entire device is only 2.1 µm2, which compares favorably to other silicon-based modulators. A modulation speed of at least 300 MHz is detected from the electrical simulator after sidewall doping is introduced which is suitable for sensing or fiber to the home (FTTH) technologies, where speed can be traded for low cost and power consumption. The device does not rely on ultra-high Q, and could serve as a sensor, modulator, or passive filter with built-in calibration.

Self-powered neutron detector

International Nuclear Information System (INIS)

Goldstein, N.P.; Todt, W.H.

1976-01-01

A self-powered neutron detector is detailed wherein a thin conductive layer of low neutron cross section, high density material is disposed about an emitter core of material which spontaneously emits radiation on neutron capture. The high density material is absorptive of beta radiation emitted by decay of the emitter core activation product, but is substantially transmissive to the high average energy prompt electrons emitted by the emitter core material. (author)

Design of low power and low area passive sigma delta modulators for audio applications

CERN Document Server

Fouto, David

2017-01-01

This book presents the study, design, modulation, optimization and implementation of low power, passive DT-ΣΔMs for use in audio applications. The high gain and bandwidth amplifier normally used for integration in ΣΔ modulation, is replaced by passive, switched-capacitor branches working under the Ultra Incomplete Settling (UIS) condition, leading to a reduction of the consumed power. The authors describe a design process that uses high level models and an optimization process based in genetic algorithms to achieve the desired performance.

Hybrid NEMS-CMOS Architectures for Ultra Low Power Smart Systems : Architectures for Ultra Low Power Smart Systems

NARCIS (Netherlands)

Enachescu, M.

2016-01-01

The availability of inexpensive and powerful processors provides the means for the computation ecosystem to change its fundamental paradigm towards the Internet of Things (IoT) where ubiquitous nanosystems add intelligence to every object that surrounds us. The new trend for most of those systems is

Self-Powered, Flexible, and Solution-Processable Perovskite Photodetector Based on Low-Cost Carbon Cloth.

Science.gov (United States)

Sun, Haoxuan; Lei, Tianyu; Tian, Wei; Cao, Fengren; Xiong, Jie; Li, Liang

2017-07-01

Flexible perovskite photodetectors are usually constructed on indium-tin-oxide-coated polymer substrates, which are expensive, fragile, and not resistant to high temperature. Herein, for the first time, a high-performance flexible perovskite photodetector is fabricated based on low-cost carbon cloth via a facile solution processable strategy. In this device, perovskite microcrystal and Spiro-OMeTAD (hole transporting material) blended film act as active materials for light detection, and carbon cloth serves as both a flexible substrate and a conductive electrode. The as-fabricated photodetector shows a broad spectrum response from ultraviolet to near-infrared light, high responsivity, fast response speed, long-term stability, and self-powered capability. Flexible devices show negligible degradation after several tens of bending cycles and at the extremely bending angle of 180°. This work promises a new technique to construct flexible, high-performance photodetectors with low cost and self-powered capability. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A wide range ultra-low power Phase-Locked Loop with automatic frequency setting in 130 nm CMOS technology for data serialisation

International Nuclear Information System (INIS)

Firlej, M.; Fiutowski, T.; Idzik, M.; Moroń, J.; Świentek, K.

2015-01-01

The design and measurements results of a wide frequency range ultra-low power Phase-Locked Loop (PLL) for applications in readout systems of particle physics detectors are presented. The PLL was fabricated in a 130 nm CMOS technology. To allow the implementation of different data serialisation schemes multiple division factors (6, 8, 10, 16) were implemented in the PLL feedback loop. The main PLL block—VCO works in 16 frequency ranges/modes, switched either manually or automatically. A dedicated automatic frequency mode switching circuit was developed to allow simple frequency tuning. Although the PLL was designed and simulated for a frequency range of 30 MHz–3 GHz, due to the SLVS interface limits, the measurements were done only up to 1.3 GHz. The full PLL functionality was experimentally verified, confirming a very low and frequency scalable power consumption (0.7 mW at 1 GHz)

A wide range ultra-low power Phase-Locked Loop with automatic frequency setting in 130 nm CMOS technology for data serialisation

Science.gov (United States)

Firlej, M.; Fiutowski, T.; Idzik, M.; Moroń, J.; Świentek, K.

2015-12-01

The design and measurements results of a wide frequency range ultra-low power Phase-Locked Loop (PLL) for applications in readout systems of particle physics detectors are presented. The PLL was fabricated in a 130 nm CMOS technology. To allow the implementation of different data serialisation schemes multiple division factors (6, 8, 10, 16) were implemented in the PLL feedback loop. The main PLL block—VCO works in 16 frequency ranges/modes, switched either manually or automatically. A dedicated automatic frequency mode switching circuit was developed to allow simple frequency tuning. Although the PLL was designed and simulated for a frequency range of 30 MHz-3 GHz, due to the SLVS interface limits, the measurements were done only up to 1.3 GHz. The full PLL functionality was experimentally verified, confirming a very low and frequency scalable power consumption (0.7 mW at 1 GHz).

Self-oscillating modulators for direct energy conversion audio power amplifiers

Energy Technology Data Exchange (ETDEWEB)

Ljusev, P.; Andersen, Michael A.E.

2005-07-01

Direct energy conversion audio power amplifier represents total integration of switching-mode power supply and Class D audio power amplifier into one compact stage, achieving high efficiency, high level of integration, low component count and eventually low cost. This paper presents how self-oscillating modulators can be used with the direct switching-mode audio power amplifier to improve its performance by providing fast hysteretic control with high power supply rejection ratio, open-loop stability and high bandwidth. Its operation is thoroughly analyzed and simulated waveforms of a prototype amplifier are presented. (au)

Self-powered wireless disposable sensor for welfare application.

Science.gov (United States)

Douseki, Takakuni; Tanaka, Ami

2013-01-01

A self-powered urinary incontinence sensor consisting of a flexible urine-activated battery and a wireless transmitter has been developed as an application for wireless biosensor networks. The flexible urine-activated battery is embedded in a disposal diaper and makes possible both the sensing of urine leakage and self-powered operation. An intermittent power-supply circuit that uses an electric double-layer capacitor (EDLC) with a small internal resistance suppresses the supply voltage drop due to the large internal resistance of the battery. This circuit supplies the power to a wireless transmitter. A 315-MHz-band wireless transmitter performs low-power operation. To verify the effectiveness of the circuit scheme, we fabricated a prototype sensor system. When 80 cc of urine is poured onto the diaper, the battery outputs a voltage of 1 V; and the sensor can transmit an ID signal over a distance of 5 m.

Review of the coal-fired, over-supercritical and ultra-supercritical steam power plants

Science.gov (United States)

Tumanovskii, A. G.; Shvarts, A. L.; Somova, E. V.; Verbovetskii, E. Kh.; Avrutskii, G. D.; Ermakova, S. V.; Kalugin, R. N.; Lazarev, M. V.

2017-02-01

The article presents a review of developments of modern high-capacity coal-fired over-supercritical (OSC) and ultra-supercritical (USC) steam power plants and their implementation. The basic engineering solutions are reported that ensure the reliability, economic performance, and low atmospheric pollution levels. The net efficiency of the power plants is increased by optimizing the heat balance, improving the primary and auxiliary equipment, and, which is the main thing, by increasing the throttle conditions. As a result of the enhanced efficiency, emissions of hazardous substances into the atmosphere, including carbon dioxide, the "greenhouse" gas, are reduced. To date, the exhaust steam conditions in the world power industry are p 0 ≈ 30 MPa and t 0 = 610/620°C. The efficiency of such power plants reaches 47%. The OSC plants are being operated in Germany, Denmark, Japan, China, and Korea; pilot plants are being developed in Russia. Currently, a project of a power plant for the ultra-supercritical steam conditions p 0 ≈ 35 MPa and t 0 = 700/720°C with efficiency of approximately 50% is being studied in the EU within the framework of the Thermie AD700 program, project AD 700PF. Investigations in this field have also been launched in the United States, Japan, and China. Engineering solutions are also being sought in Russia by the All-Russia Thermal Engineering Research Institute (VTI) and the Moscow Power Engineering Institute. The stated steam parameter level necessitates application of new materials, namely, nickel-base alloys. Taking into consideration high costs of nickel-base alloys and the absence in Russia of technologies for their production and manufacture of products from these materials for steam-turbine power plants, the development of power plants for steam parameters of 32 MPa and 650/650°C should be considered to be the first stage in creating the USC plants as, to achieve the above parameters, no expensive alloys are require. To develop and

Nanogenerators for Self-Powered Gas Sensing

Science.gov (United States)

Wen, Zhen; Shen, Qingqing; Sun, Xuhui

2017-10-01

Looking toward world technology trends over the next few decades, self-powered sensing networks are a key field of technological and economic driver for global industries. Since 2006, Zhong Lin Wang's group has proposed a novel concept of nanogenerators (NGs), including piezoelectric nanogenerator and triboelectric nanogenerator, which could convert a mechanical trigger into an electric output. Considering motion ubiquitously exists in the surrounding environment and for any most common materials used every day, NGs could be inherently served as an energy source for our daily increasing requirements or as one of self-powered environmental sensors. In this regard, by coupling the piezoelectric or triboelectric properties with semiconducting gas sensing characterization, a new research field of self-powered gas sensing has been proposed. Recent works have shown promising concept to realize NG-based self-powered gas sensors that are capable of detecting gas environment without the need of external power sources to activate the gas sensors or to actively generate a readout signal. Compared with conventional sensors, these self-powered gas sensors keep the approximate performance. Meanwhile, these sensors drastically reduce power consumption and additionally reduce the required space for integration, which are significantly suitable for the wearable devices. This paper gives a brief summary about the establishment and latest progress in the fundamental principle, updated progress and potential applications of NG-based self-powered gas sensing system. The development trend in this field is envisaged, and the basic configurations are also introduced.

Design, control and power management of a battery/ultra-capacitor hybrid system for small electric vehicles

DEFF Research Database (Denmark)

Li, Zhihao; Onar, Omer; Khaligh, Alireza

2009-01-01

This paper introduces design, control, and power management of a battery/ultra-capacitor hybrid system, utilized for small electric vehicles (EV). The batteries are designed and controlled to work as the main energy storage source of the vehicle, supplying average power to the load; and the ultra...

Towards Flexible Self-powered Micro-scale Integrated Systems

KAUST Repository

Rojas, Jhonathan Prieto

2014-04-01

Today’s information-centered world leads the ever-increasing consumer demand for more powerful, multifunctional portable devices. Additionally, recent developments on long-lasting energy sources and compliant, flexible systems, have introduced new required features to the portable devices industry. For example, wireless sensor networks are in urgent need of self-sustainable, easy-to-deploy, mobile platforms, wirelessly interconnected and accessible through a cloud computing system. The objective of my doctoral work is to develop integration strategies to effectively fabricate mechanically flexible, energy-independent systems, which could empower sensor networks for a great variety of new exciting applications. The first module, flexible electronics, can be achieved through several techniques and materials. Our main focus is to bring mechanical flexibility to the state-of-the-art high performing silicon-based electronics, with billions of ultra-low power, nano-sized transistors. Therefore, we have developed a low-cost batch fabrication process to transform standard, rigid, mono-crystalline silicon (100) wafer with devices, into a thin (5-20 m), mechanically flexible, optically semi-transparent silicon fabric. Recycling of the remaining wafer is possible, enabling generation of multiple fabrics to ensure lowcost and optimal utilization of the whole substrate. We have shown mono, amorphous and poly-crystalline silicon and silicon dioxide fabrics, featuring industry’s most advanced high-/metal-gate based capacitors and transistors. The second module consists on the development of efficient energy scavenging systems. First, we have identified an innovative and relatively young technology, which can address at the same time two of the main concerns of human kind: water and energy. Microbial fuel cells (MFC) are capable of producing energy out the metabolism of bacteria while treating wastewater. We have developed two micro-liter MFC designs, one with carbon

Wide and ultra-wide bandgap oxides: where paradigm-shift photovoltaics meets transparent power electronics

Science.gov (United States)

Pérez-Tomás, Amador; Chikoidze, Ekaterine; Jennings, Michael R.; Russell, Stephen A. O.; Teherani, Ferechteh H.; Bove, Philippe; Sandana, Eric V.; Rogers, David J.

2018-03-01

Oxides represent the largest family of wide bandgap (WBG) semiconductors and also offer a huge potential range of complementary magnetic and electronic properties, such as ferromagnetism, ferroelectricity, antiferroelectricity and high-temperature superconductivity. Here, we review our integration of WBG and ultra WBG semiconductor oxides into different solar cells architectures where they have the role of transparent conductive electrodes and/or barriers bringing unique functionalities into the structure such above bandgap voltages or switchable interfaces. We also give an overview of the state-of-the-art and perspectives for the emerging semiconductor β- Ga2O3, which is widely forecast to herald the next generation of power electronic converters because of the combination of an UWBG with the capacity to conduct electricity. This opens unprecedented possibilities for the monolithic integration in solar cells of both self-powered logic and power electronics functionalities. Therefore, WBG and UWBG oxides have enormous promise to become key enabling technologies for the zero emissions smart integration of the internet of things.

An Electronic System for Ultra-low Power Hearing Implants

Science.gov (United States)

2013-02-15

Battery Charger Circuit ," IEEE Transactions on Biomedical Circuits and Systems, Vol. 5, No.2, pp. 131-137,2011. [6] K. H. Wee, L. Turicchia, and R...analyzers [1], [2], useful in several hearing systems. 4) We have designed and built a lithium-ion battery -recharging circuit that exploits a novel analog...lab and the use of intelligent low-power filters and circuits have been successful in reducing noise exposure while improving speech intelligibility

Low-Power and Reliable Communications for UWB-Based Wireless Monitoring Sensor Networks in Underground Mine Tunnels

OpenAIRE

Abou El-Nasr, Mohamad; Shaban, Heba

2015-01-01

This paper investigates the bit-error-rate (BER) and maximum allowable data throughput (MADTh) performance of a novel low-power mismatched Rake receiver structure for ultra wideband (UWB) wireless monitoring sensor networks in underground mine tunnels. This receive node structure provides a promising solution for low-power and reliable communications in underground mine tunnels with more than 90% reduction in power consumption. The BER and MADTh of the proposed receive nodes are investigated ...

Ultra-low power, highly uniform polymer memory by inserted multilayer graphene electrode

International Nuclear Information System (INIS)

Jang, Byung Chul; Kim, Jong Yun; Koo, Beom Jun; Yang, Sang Yoon; Choi, Sung-Yool; Seong, Hyejeong; Im, Sung Gap; Kim, Sung Kyu

2015-01-01

Filament type resistive random access memory (RRAM) based on polymer thin films is a promising device for next generation, flexible nonvolatile memory. However, the resistive switching nonuniformity and the high power consumption found in the general filament type RRAM devices present critical issues for practical memory applications. Here, we introduce a novel approach not only to reduce the power consumption but also to improve the resistive switching uniformity in RRAM devices based on poly(1,3,5-trimethyl-3,4,5-trivinyl cyclotrisiloxane) by inserting multilayer graphene (MLG) at the electrode/polymer interface. The resistive switching uniformity was thereby significantly improved, and the power consumption was markedly reduced by 250 times. Furthermore, the inserted MLG film enabled a transition of the resistive switching operation from unipolar resistive switching to bipolar resistive switching and induced self-compliance behavior. The findings of this study can pave the way toward a new area of application for graphene in electronic devices. (paper)

Adiabatic superconducting cells for ultra-low-power artificial neural networks

Directory of Open Access Journals (Sweden)

Andrey E. Schegolev

2016-10-01

Full Text Available We propose the concept of using superconducting quantum interferometers for the implementation of neural network algorithms with extremely low power dissipation. These adiabatic elements are Josephson cells with sigmoid- and Gaussian-like activation functions. We optimize their parameters for application in three-layer perceptron and radial basis function networks.

Does power corrupt or enable? When and why power facilitates self-interested behavior.

Science.gov (United States)

DeCelles, Katherine A; DeRue, D Scott; Margolis, Joshua D; Ceranic, Tara L

2012-05-01

Does power corrupt a moral identity, or does it enable a moral identity to emerge? Drawing from the power literature, we propose that the psychological experience of power, although often associated with promoting self-interest, is associated with greater self-interest only in the presence of a weak moral identity. Furthermore, we propose that the psychological experience of power is associated with less self-interest in the presence of a strong moral identity. Across a field survey of working adults and in a lab experiment, individuals with a strong moral identity were less likely to act in self-interest, yet individuals with a weak moral identity were more likely to act in self-interest, when subjectively experiencing power. Finally, we predict and demonstrate an explanatory mechanism behind this effect: The psychological experience of power enhances moral awareness among those with a strong moral identity, yet decreases the moral awareness among those with a weak moral identity. In turn, individuals' moral awareness affects how they behave in relation to their self-interest. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

BioRadioTransmitter: a self-powered wireless glucose-sensing system.

Science.gov (United States)

Hanashi, Takuya; Yamazaki, Tomohiko; Tsugawa, Wakako; Ikebukuro, Kazunori; Sode, Koji

2011-09-01

Although an enzyme fuel cell can be utilized as a glucose sensor, the output power generated is too low to power a device such as a currently available transmitter and operating system, and an external power source is required for operating an enzyme-fuel-cell-based biosensing system. We proposed a novel biosensor that we named BioCapacitor, in which a capacitor serves as a transducer. In this study, we constructed a new BioCapacitor-based system with an added radio-transmitter circuit and a miniaturized enzyme fuel cell. A miniaturized direct-electron-transfer-type compartmentless enzyme fuel cell was constructed with flavin adenine dinucleotide-dependent glucose dehydrogenase complex-based anode and a bilirubin-oxidase-based cathode. For construction of a BioRadioTransmitter wireless sensing system, a capacitor, an ultra-low-voltage charge-pump-integrated circuit, and Hartley oscillator circuit were connected to the miniaturized enzyme fuel cell. A radio-receiver circuit, comprising two field-effect transistors and a coil as an antenna, was used to amplify the signal generated from the biofuel cells. Radio wave signals generated by the BioRadioTransmitter were received, amplified, and converted from alternate to direct current by the radio receiver. When the capacitor discharges in the presence of glucose, the BioRadioTransmitter generates a radio wave, which is monitored by a radio receiver connected wirelessly to the sensing device. Magnitude of the radio wave transmission frequency change observed at the radio receiver was correlated to glucose concentration in the fuel cells. We constructed a stand-alone, self-powered, wireless glucose-sensing system called a BioRadioTransmitter by using a radio transmitter in which the radio wave transmission frequency changes with the glucose concentration in the fuel cell. The BioRadioTransmitter is a significant advance toward construction of an implantable continuous glucose monitor. © 2011 Diabetes Technology Society.

Ultra Clean 1.1MW High Efficiency Natural Gas Engine Powered System

Energy Technology Data Exchange (ETDEWEB)

Zurlo, James; Lueck, Steve

2011-08-31

Dresser, Inc. (GE Energy, Waukesha gas engines) will develop, test, demonstrate, and commercialize a 1.1 Megawatt (MW) natural gas fueled combined heat and power reciprocating engine powered package. This package will feature a total efficiency > 75% and ultra low CARB permitting emissions. Our modular design will cover the 1 – 6 MW size range, and this scalable technology can be used in both smaller and larger engine powered CHP packages. To further advance one of the key advantages of reciprocating engines, the engine, generator and CHP package will be optimized for low initial and operating costs. Dresser, Inc. will leverage the knowledge gained in the DOE - ARES program. Dresser, Inc. will work with commercial, regulatory, and government entities to help break down barriers to wider deployment of CHP. The outcome of this project will be a commercially successful 1.1 MW CHP package with high electrical and total efficiency that will significantly reduce emissions compared to the current central power plant paradigm. Principal objectives by phases for Budget Period 1 include: • Phase 1 – market study to determine optimum system performance, target first cost, lifecycle cost, and creation of a detailed product specification. • Phase 2 – Refinement of the Waukesha CHP system design concepts, identification of critical characteristics, initial evaluation of technical solutions, and risk mitigation plans. Background

Power management circuits for self-powered systems based on micro-scale solar energy harvesting

Science.gov (United States)

Yoon, Eun-Jung; Yu, Chong-Gun

2016-03-01

In this paper, two types of power management circuits for self-powered systems based on micro-scale solar energy harvesting are proposed. First, if a solar cell outputs a very low voltage, less than 0.5 V, as in miniature solar cells or monolithic integrated solar cells, such that it cannot directly power the load, a voltage booster is employed to step up the solar cell's output voltage, and then a power management unit (PMU) delivers the boosted voltage to the load. Second, if the output voltage of a solar cell is enough to drive the load, the PMU directly supplies the load with solar energy. The proposed power management systems are designed and fabricated in a 0.18-μm complementary metal-oxide-semiconductor process, and their performances are compared and analysed through measurements.

Self-powered radiation detectors

International Nuclear Information System (INIS)

Goldstein, N.P.; Todt, W.H.

1982-01-01

A self-powered nuclear radiation detector has an emitter electrode of an alloy of a first major constituent metal having a desired high radiation response, and a second minor constituent which imparts to the alloy a desired thermal or mechanical characteristic without diminishing the desired high radiation response. A gamma responsive self-powered detector is detailed which has an emitter with lead as the major constituent, with the minor constituent selected from aluminum, copper, nickel, platinum, or zinc. (author)

Low Power Design with High-Level Power Estimation and Power-Aware Synthesis

CERN Document Server

Ahuja, Sumit; Shukla, Sandeep Kumar

2012-01-01

Low-power ASIC/FPGA based designs are important due to the need for extended battery life, reduced form factor, and lower packaging and cooling costs for electronic devices. These products require fast turnaround time because of the increasing demand for handheld electronic devices such as cell-phones, PDAs and high performance machines for data centers. To achieve short time to market, design flows must facilitate a much shortened time-to-product requirement. High-level modeling, architectural exploration and direct synthesis of design from high level description enable this design process. This book presents novel research techniques, algorithms,methodologies and experimental results for high level power estimation and power aware high-level synthesis. Readers will learn to apply such techniques to enable design flows resulting in shorter time to market and successful low power ASIC/FPGA design. Integrates power estimation and reduction for high level synthesis, with low-power, high-level design; Shows spec...

Optimal Self-Tuning PID Controller Based on Low Power Consumption for a Server Fan Cooling System.

Science.gov (United States)

Lee, Chengming; Chen, Rongshun

2015-05-20

Recently, saving the cooling power in servers by controlling the fan speed has attracted considerable attention because of the increasing demand for high-density servers. This paper presents an optimal self-tuning proportional-integral-derivative (PID) controller, combining a PID neural network (PIDNN) with fan-power-based optimization in the transient-state temperature response in the time domain, for a server fan cooling system. Because the thermal model of the cooling system is nonlinear and complex, a server mockup system simulating a 1U rack server was constructed and a fan power model was created using a third-order nonlinear curve fit to determine the cooling power consumption by the fan speed control. PIDNN with a time domain criterion is used to tune all online and optimized PID gains. The proposed controller was validated through experiments of step response when the server operated from the low to high power state. The results show that up to 14% of a server's fan cooling power can be saved if the fan control permits a slight temperature response overshoot in the electronic components, which may provide a time-saving strategy for tuning the PID controller to control the server fan speed during low fan power consumption.

Optimal Self-Tuning PID Controller Based on Low Power Consumption for a Server Fan Cooling System

Directory of Open Access Journals (Sweden)

Chengming Lee

2015-05-01

Full Text Available Recently, saving the cooling power in servers by controlling the fan speed has attracted considerable attention because of the increasing demand for high-density servers. This paper presents an optimal self-tuning proportional-integral-derivative (PID controller, combining a PID neural network (PIDNN with fan-power-based optimization in the transient-state temperature response in the time domain, for a server fan cooling system. Because the thermal model of the cooling system is nonlinear and complex, a server mockup system simulating a 1U rack server was constructed and a fan power model was created using a third-order nonlinear curve fit to determine the cooling power consumption by the fan speed control. PIDNN with a time domain criterion is used to tune all online and optimized PID gains. The proposed controller was validated through experiments of step response when the server operated from the low to high power state. The results show that up to 14% of a server’s fan cooling power can be saved if the fan control permits a slight temperature response overshoot in the electronic components, which may provide a time-saving strategy for tuning the PID controller to control the server fan speed during low fan power consumption.

Exergoeconomic Evaluation of a Modern Ultra-Supercritical Power Plant

Directory of Open Access Journals (Sweden)

Lingnan Wu

2012-09-01

Full Text Available In this paper, the exergoeconomic analysis was conducted to an existing ultra-supercritical coal-fired power plant in China to understand the cost-formation process, to evaluate the economic performance of each component and to find possible solutions for more cost-effective designs. The total revenue requirement (TRR and the specific exergy costing (SPECO methods were applied for economic analysis and exergy costing, respectively. Quantitative balances of exergy and exergetic costs as well as necessary auxiliary equations for both individual component and the overall system were established. The results show that the exergoeconomic factors of the furnace and heat exchangers at low temperature levels, including air preheater and low-pressure feedwater preheaters, are rather small; while those of other components are relatively large. Moving more heat absorption into furnace to use the effective radiation heat transfer, increasing the air preheating temperature and adding more low pressure feedwater preheaters can be promising solutions for future design.

Low power constant fraction discriminator

International Nuclear Information System (INIS)

Krishnan, Shanti; Raut, S.M.; Mukhopadhyay, P.K.

2001-01-01

This paper describes the design of a low power ultrafast constant fraction discriminator, which significantly reduces the power consumption. A conventional fast discriminator consumes about 1250 MW of power whereas this low power version consumes about 440 MW. In a multi detector system, where the number of discriminators is very large, reduction of power is of utmost importance. This low power discriminator is being designed for GRACE (Gamma Ray Atmospheric Cerenkov Experiments) telescope where 1000 channels of discriminators are required. A novel method of decreasing power consumption has been described. (author)

Low power arcjet performance

Science.gov (United States)

Curran, Francis M.; Sarmiento, Charles J.

1990-01-01

An experimental investigation was performed to evaluate arcjet operation at low power. A standard, 1 kW, constricted arcjet was run using nozzles with three different constrictor diameters. Each nozzle was run over a range of current and mass flow rates to explore stability and performance in the low power regime. A standard pulse-width modulated power processor was modified to accommodate the high operating voltages required under certain conditions. Stable, reliable operation at power levels below 0.5 kW was obtained at efficiencies between 30 and 40 percent. The operating range was found to be somewhat dependent on constrictor geometry at low mass flow rates. Quasi-periodic voltage fluctuations were observed at the low power end of the operating envelope. The nozzle insert geometry was found to have little effect on the performance of the device. The observed performance levels show that specific impulse levels above 350 seconds can be obtained at the 0.5 kW power level.

Power Efficient Design of DisplayPort (7.0) Using Low-voltage differential signaling IO Standard Via UltraScale Field Programming Gate Arrays

DEFF Research Database (Denmark)

Das, Bhagwan; Abdullah, M.F.L.; Hussain, Dil muhammed Akbar

2017-01-01

Port (7.0) need be reduced. In this paper, a power efficient design for DisplayPort (7.0) is proposed using LVDS IO Standard. The proposed design is tested for different frequencies; 500 MHz, 700 MHz, 1.0 GHz, and 1.6 GHz. The design is implemented using vhdl in UltraScale FPGA. It is determined...... the designed vhdl based design of DisplayPort (7.0) can reduced 92% using LVDS IO Standard for all frequencies; 500 MHz, 700 MHz, 1.0 GHz, and 1.6 GHz, compared to vhdl based design of DisplayPort (7.0) without using IO Standard. The proposed design of vhdl based design of DisplayPort (7.0) using LVDS IO...... Standard offers no power consumption for DisplayPort (7.0) in standby mode. The vhdl based design of DisplayPort (7.0) using LVDS IO Standard will be helpful to process the high resolution video at low power consumption....

An ultra-low-power area-efficient non-volatile memory in a 0.18 μm single-poly CMOS process for passive RFID tags

International Nuclear Information System (INIS)

Jia Xiaoyun; Feng Peng; Zhang Shengguang; Wu Nanjian; Zhao Baiqin; Liu Su

2013-01-01

This paper presents an ultra-low-power area-efficient non-volatile memory (NVM) in a 0.18 μm single-poly standard CMOS process for passive radio frequency identification (RFID) tags. In the memory cell, a novel low-power operation method is proposed to realize bi-directional Fowler—Nordheim tunneling during write operation. Furthermore, the cell is designed with PMOS transistors and coupling capacitors to minimize its area. In order to improve its reliability, the cell consists of double floating gates to store the data, and the 1 kbit NVM was implemented in a 0.18 μm single-poly standard CMOS process. The area of the memory cell and 1 kbit memory array is 96 μm 2 and 0.12 mm 2 , respectively. The measured results indicate that the program/erase voltage ranges from 5 to 6 V The power consumption of the read/write operation is 0.19 μW/0.69 μW at a read/write rate of (268 kb/s)/(3.0 kb/s). (semiconductor integrated circuits)

Energy Harvesting for Self-Powered, Ultra-Low Power Microsystems With a Focus on Vibration-Based Electromechanical Conversion

Science.gov (United States)

2009-09-01

capacitor responsible for charge. Figure 25. Half Bridge Power Harvester with Leakage Resistance [From 70] The resistor accounts for the voltage...REV PAP, 1996. [63] M. Umeda, K. Nakamura, and S. Ueha, “Energy storage characteristics of a piezo - generator using impact induced vibration...Japanese journal of applied physics, vol. 36, pp. 3146–3151, 1997. [64] M. Kimura, “ Piezo -electricity generation device,” U.S. Patent 812070, September

Sexual aggression when power is new: Effects of acute high power on chronically low-power individuals.

Science.gov (United States)

Williams, Melissa J; Gruenfeld, Deborah H; Guillory, Lucia E

2017-02-01

Previous theorists have characterized sexually aggressive behavior as an expression of power, yet evidence that power causes sexual aggression is mixed. We hypothesize that power can indeed create opportunities for sexual aggression-but that it is those who chronically experience low power who will choose to exploit such opportunities. Here, low-power men placed in a high-power role showed the most hostility in response to a denied opportunity with an attractive woman (Studies 1 and 2). Chronically low-power men and women given acute power were the most likely to say they would inappropriately pursue an unrequited workplace attraction (Studies 3 and 4). Finally, having power over an attractive woman increased harassment behavior among men with chronic low, but not high, power (Study 5). People who see themselves as chronically denied power appear to have a stronger desire to feel powerful and are more likely to use sexual aggression toward that end. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Ultra-long-pulse microwave negative high voltage power supply with fast protection

International Nuclear Information System (INIS)

Xu Weihua; Wu Junshuan; Zheng Guanghua; Huang Qiaolin; Yang Chunsheng; Zhou Yuanwei; Chen Yonghao

1998-01-01

Two 1.4 MW high voltage power supply (HVPS) modules with 3-5 s pulse duration have been developed for LHCD experiment in the HT-7 tokamak. The power source consists of a pulsed generator and the electric circuit. Duration of the ultra-long-pulse is controlled by switching-on dc relay immediately and switching-off ac contactor after a given time, and the fast protection is executed by a crowbar. Due to the soft starting of the power source, the problem of overvoltage induced by dc relay switching-on has been solved. Each power supply module outputs a rated power (-35 kV, 40 A) on the dummy load. With the klystrons connected as the load of the power supply modules, LHCD experiments have been conducted successfully in the HT-7 tokamak

Design and fabrication of self-powered micro-harvesters rotating and vibrated micro-power systems

CERN Document Server

Pan, C T; Lin, Liwei; Chen, Ying-Chung

2013-01-01

Presents the latest methods for designing and fabricating self-powered micro-generators and energy harvester systems Design and Fabrication of Self-Powered Micro-Harvesters introduces the latest trends of self-powered generators and energy harvester systems, including the design, analysis and fabrication of micro power systems. Presented in four distinct parts, the authors explore the design and fabrication of: vibration-induced electromagnetic micro-generators; rotary electromagnetic micro-generators; flexible piezo-micro-generator with various widths; and PVDF electrospunpiezo-energy with

Wireless, Ultra-Low-Power Implantable Sensor for Chronic Bladder Pressure Monitoring.

Science.gov (United States)

Majerus, Steve J A; Garverick, Steven L; Suster, Michael A; Fletter, Paul C; Damaser, Margot S

2012-06-01

The wireless implantable/intracavity micromanometer (WIMM) system was designed to fulfill the unmet need for a chronic bladder pressure sensing device in urological fields such as urodynamics for diagnosis and neuromodulation for bladder control. Neuromodulation in particular would benefit from a wireless bladder pressure sensor which could provide real-time pressure feedback to an implanted stimulator, resulting in greater bladder capacity while using less power. The WIMM uses custom integrated circuitry, a MEMS transducer, and a wireless antenna to transmit pressure telemetry at a rate of 10 Hz. Aggressive power management techniques yield an average current draw of 9 μ A from a 3.6-Volt micro-battery, which minimizes the implant size. Automatic pressure offset cancellation circuits maximize the sensing dynamic range to account for drifting pressure offset due to environmental factors, and a custom telemetry protocol allows transmission with minimum overhead. Wireless operation of the WIMM has demonstrated that the external receiver can receive the telemetry packets, and the low power consumption allows for at least 24 hours of operation with a 4-hour wireless recharge session.

Self-powered flux detectors

International Nuclear Information System (INIS)

Shields, R.B.

1983-02-01

This bibliography attempts to cover the published literature on the class of radiation detectors most often referred to as 'self-powered'. For this purpose, self-powered detectors are defined as those that have two or more conducting electrodes separated by solid insulation and that generate a signal current without an external power source. Primary sensitivity is unrestricted, but it is usually to neutrons or gamma-rays. The main application is in the core of a nuclear reactor. All relevant facets of the subject are covered including: theory, experiment, development, design, manufacture, instrumentation and application. In addition to the usual reference information, various other designations are included where available, such as CONF-and abstract serial numbers. Where possible, a summary of the content is given with emphasis on specific results and conclusions. Indexing is by author and subject

Design of Low Inductance Switching Power Cell for GaN HEMT Based Inverter

DEFF Research Database (Denmark)

Gurpinar, Emre; Iannuzzo, Francesco; Yang, Yongheng

2018-01-01

. The design of gate drivers for the GaN HEMT devices is presented. Parasitic inductance and resistance of the proposed design are extracted with finite element analysis and discussed. Common-mode behaviours based on the SPICE model of the converter are analyzed. Experimental results on the designed 3L......In this paper, an ultra-low inductance power cell is designed for a three-Level Active Neutral Point Clamped (3LANPC) based on 650 V gallium nitride (GaN) HEMT devices. The 3L-ANPC topology with GaN HEMT devices and the selected modulation scheme suitable for wide-bandgap (WBG) devices...... are presented. The commutation loops, which mainly contribute to voltage overshoots and increase of switching losses, are discussed. The ultra-low inductance power cell design based on a four-layer Printed Circuit Board (PCB) with the aim to maximize the switching performance of GaN HEMTs is explained...

Authenticity as a Mediator of the Relationship Between Power Contingent Self-Esteem and Subjective Well-Being

Directory of Open Access Journals (Sweden)

Yi’nan Wang

2018-06-01

Full Text Available Drawing on Eastern wisdom and Self-Determination Theory (Deci and Ryan, 1995, the current study conceptualized a new form of maladaptive self-esteem, the power contingent self-esteem, which is extremely contingent on one’s sense of power, and posits it is related to low subjective well-being by making people experience less authenticity. In Study 1, we found that general power contingent self-esteem was consistently linked to low subjective well-being. More importantly, the negative relationship between power contingent self-esteem and subjective well-being was mediated by authenticity. Study 2 further confirmed the mediation effect between power contingent self-esteem role and satisfaction through authenticity across four different roles (work, romance, friendship, and parent–child relationships. The finding of the negative relationship between power contingent self-esteem and subjective well-being via authenticity contributes to understanding the complicated association between power, self-esteem, and life satisfaction.

Report on achievement in developing an ultra low loss power element technology. Survey on practical application of the next generation power semiconductor devices; 1998 nendo choteisonshitsu denryoku soshi gijutsu kaihatsu seika hokokusho. Jisedai power handotai device jitsuyoka chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

Trends were surveyed for development of an ultra low loss power element. Performance improvement has been progressed on power semiconductor elements by using Si as the raw material, but loss reduction has come close to the physical limit. SiC is expected of possibility to go beyond this limit. SiC is so very excellent that its band gap is two to three times greater, insulation breakdown electric field is 7.5 times higher, temperature to become a true semiconductor is three to four times higher than those of Si. The wide gap can reduce high temperature leaking current in p-n junctions, and the increased authenticity temperature can increase the upper limit for operation temperature. The insulation breakdown strength being higher by one digit can reduce the drift layer thickness, and is expected to dramatically reduce the loss. The problem is that high quality crystals have not been obtained to date. One of the promising application fields is electric vehicle. The device currently using the power element in the largest scale is used in frequency converting stations to link the 50-Hz power network in the eastern part of Japan to the 60-Hz network in the western part of Japan. Surveys were carried out on the Sakuma frequency converting station and the New Shinano substation. (NEDO)

A low power 20 GHz comparator in 90 nm COMS technology

Science.gov (United States)

Kai, Tang; Qiao, Meng; Zhigong, Wang; Ting, Guo

2014-05-01

A low power 20 GHz CMOS dynamic latched regeneration comparator for ultra-high-speed, low-power analog-to-digital converters (ADCs) is proposed. The time constant in both the tracking and regeneration phases of the latch are analyzed based on the small signal model. A dynamic source-common logic (SCL) topology is adopted in the master-slave latch to increase the tracking and regeneration speeds. Implemented in 90 nm CMOS technology, this comparator only occupies a die area of 65 × 150 μm2 with a power dissipation of 14 mW from a 1.2 V power supply. The measurement results show that the comparator can work up to 20 GHz. Operating with an input frequency of 1 GHz, the circuit can oversample up to 20 Giga-sampling-per-second (GSps) with 5 bits resolution; while operating at Nyquist, the comparator can sample up to 20 GSps with 4 bits resolution. The comparator has been successfully used in a 20 GSps flash ADC and the circuit can be also used in other high speed applications.

A low power 12-bit ADC for nuclear instrumentation

International Nuclear Information System (INIS)

Adachi, R.; Landis, D.; Madden, N.; Silver, E.; LeGros, M.

1992-10-01

A low power, successive approximation, analog-to-digital converter (ADC) for low rate, low cost, battery powered applications is described. The ADC is based on a commercial 50 mW successive approximation CMOS device (CS5102). An on-chip self-calibration circuit reduces the inherent differential nonlinearity to 7%. A further reduction of the differential nonlinearity to 0.5% is attained with a four bit Gatti function. The Gatti function is distributed to minimize battery power consumption. All analog functions reside with the ADC while the noisy digital functions reside in the personal computer based histogramming memory. Fiber optic cables carry afl digital information between the ADC and the personal computer based histogramming memory

Ultra-low-frequency dust-electromagnetic modes in self-gravitating magnetized dusty plasmas

International Nuclear Information System (INIS)

Mamun, A.A.

1999-07-01

Obliquely propagating ultra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized two fluid dusty plasma system have been investigated. Two special cases, namely, dust-Alfven mode propagating parallel to the external magnetic field and dust-magnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that these effects of self-gravitational field and dust/ion fluid temperature play no role in parallel propagating dust-Alfven mode, but in obliquely propagating dust-Alfven mode or perpendicular propagating dust-magnetosonic mode the effect of self-gravitational field plays a destabilizing role whereas the effect of dust/ion fluid temperature plays a stabilizing role. (author)

True Low-Power Self-Locking Soft Actuators.

Science.gov (United States)

Kim, Seung Jae; Kim, Onnuri; Park, Moon Jeong

2018-03-01

Natural double-layered structures observed in living organisms are known to exhibit asymmetric volume changes with environmental triggers. Typical examples are natural roots of plants, which show unique self-organized bending behavior in response to environmental stimuli. Herein, light- and electro-active polymer (LEAP) based actuators with a double-layered structure are reported. The LEAP actuators exhibit an improvement of 250% in displacement and hold an object three times heavier as compared to that in the case of conventional electro-active polymer actuators. Most interestingly, the bending motion of the LEAP actuators can be effectively locked for a few tens of minutes even in the absence of a power supply. Further, the self-locking LEAP actuators show a large and reversible bending strain of more than 2.0% and require only 6.2 mW h cm -2 of energy to hold an object for 15 min at an operating voltage of 3 V. These novel self-locking soft actuators should find wide applicability in artificial muscles, biomedical microdevices, and various innovative soft robot technologies. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Self-powered radiation detector

International Nuclear Information System (INIS)

Playfoot, K.C.; Bauer, R.F.; Goldstein, N.P.

1980-01-01

This invention relates to a self powered radiation detector requiring no excitation potential to generate a signal indicating a radiation flux. Such detectors comprise two electrically insulated electrodes, at a distance from each other. These electrodes are made of conducting materials having a different response for neutron and/or gamma ray radiation flux levels, as in nuclear power stations. This elongated detector generates an electric signal in terms of an incident flux of radiations cooperating with coaxial conductors insulated from each other and with different radiation reaction characteristics. The conductor with the greatest reaction to the radiations forms the central emitting electrode and the conductor with the least reaction to the radiations forms a tubular coaxial collecting electrode. The rhodium or cobalt tubular emitting electrode contains a ductile central conducting cable placed along the longitudinal axis of the detector. The latter is in high nickel steel with a low reaction to radiation [fr

Compact, self-regulating nuclear power source

International Nuclear Information System (INIS)

Peterson, Otis G.; Kimpland, Robert H.

2008-01-01

An inherently safe nuclear power source has been designed, that is self-stabilizing and requires no moving mechanical components. Unlike conventional designs, the proposed reactor is self-regulating through the inherent properties of uranium hydride, which serves as a combination fuel and moderator. The temperature driven mobility of the hydrogen contained in the hydride will control the nuclear activity. If the core temperature increases over the set point, the hydrogen is driven out of the core, the moderation drops and the power production decreases. If the temperature drops, the hydrogen returns and the process is reversed. Thus the design is inherently fail-safe and requires only minimal human oversight. The compact nature and inherent safety opens the possibility for low-cost mass production and operation of the reactors. This design has the capability to dramatically alter the manner in which nuclear energy is harnessed for commercial use. (author)

Ultra-low power thin film transistors with gate oxide formed by nitric acid oxidation method

International Nuclear Information System (INIS)

Kobayashi, H.; Kim, W. B.; Matsumoto, T.

2011-01-01

We have developed a low temperature fabrication method of SiO 2 /Si structure by use of nitric acid, i.e., nitric acid oxidation of Si (NAOS) method, and applied it to thin film transistors (TFT). A silicon dioxide (SiO 2 ) layer formed by the NAOS method at room temperature possesses 1.8 nm thickness, and its leakage current density is as low as that of thermally grown SiO 2 layer with the same thickness formed at ∼900 deg C. The fabricated TFTs possess an ultra-thin NAOS SiO 2 /CVD SiO 2 stack gate dielectric structure. The ultrathin NAOS SiO 2 layer effectively blocks a gate leakage current, and thus, the thickness of the gate oxide layer can be decreased from 80 to 20 nm. The thin gate oxide layer enables to decrease the operation voltage to 2 V (cf. the conventional operation voltage of TFTs with 80 nm gate oxide: 12 V) because of the low threshold voltages, i.e., -0.5 V for P-ch TFTs and 0.5 V for N-ch TFTs, and thus the consumed power decreases to 1/36 of that of the conventional TFTs. The drain current increases rapidly with the gate voltage, and the sub-threshold voltage is ∼80 mV/dec. The low sub-threshold swing is attributable to the thin gate oxide thickness and low interface state density of the NAOS SiO 2 layer. (authors)

A CMOS self-powered front-end architecture for subcutaneous event-detector devices

CERN Document Server

Colomer-Farrarons, Jordi

2011-01-01

A CMOS Self-Powered Front-End Architecture for Subcutaneous Event-Detector Devices presents the conception and prototype realization of a Self-Powered architecture for subcutaneous detector devices. The architecture is designed to work as a true/false (event detector) or threshold level alarm of some substances, ions, etc. that are detected through a three-electrodes amperometric BioSensor approach. The device is conceived as a Low-Power subcutaneous implantable application powered by an inductive link, one emitter antenna at the external side of the skin and the receiver antenna under the ski

A 6.45 μW Self-Powered SoC With Integrated Energy-Harvesting Power Management and ULP Asymmetric Radios for Portable Biomedical Systems.

Science.gov (United States)

Roy, Abhishek; Klinefelter, Alicia; Yahya, Farah B; Chen, Xing; Gonzalez-Guerrero, Luisa Patricia; Lukas, Christopher J; Kamakshi, Divya Akella; Boley, James; Craig, Kyle; Faisal, Muhammad; Oh, Seunghyun; Roberts, Nathan E; Shakhsheer, Yousef; Shrivastava, Aatmesh; Vasudevan, Dilip P; Wentzloff, David D; Calhoun, Benton H

2015-12-01

This paper presents a batteryless system-on-chip (SoC) that operates off energy harvested from indoor solar cells and/or thermoelectric generators (TEGs) on the body. Fabricated in a commercial 0.13 μW process, this SoC sensing platform consists of an integrated energy harvesting and power management unit (EH-PMU) with maximum power point tracking, multiple sensing modalities, programmable core and a low power microcontroller with several hardware accelerators to enable energy-efficient digital signal processing, ultra-low-power (ULP) asymmetric radios for wireless transmission, and a 100 nW wake-up radio. The EH-PMU achieves a peak end-to-end efficiency of 75% delivering power to a 100 μA load. In an example motion detection application, the SoC reads data from an accelerometer through SPI, processes it, and sends it over the radio. The SPI and digital processing consume only 2.27 μW, while the integrated radio consumes 4.18 μW when transmitting at 187.5 kbps for a total of 6.45 μW.

Ultra-Short-Term Wind Power Prediction Using a Hybrid Model

Science.gov (United States)

Mohammed, E.; Wang, S.; Yu, J.

2017-05-01

This paper aims to develop and apply a hybrid model of two data analytical methods, multiple linear regressions and least square (MLR&LS), for ultra-short-term wind power prediction (WPP), for example taking, Northeast China electricity demand. The data was obtained from the historical records of wind power from an offshore region, and from a wind farm of the wind power plant in the areas. The WPP achieved in two stages: first, the ratios of wind power were forecasted using the proposed hybrid method, and then the transformation of these ratios of wind power to obtain forecasted values. The hybrid model combines the persistence methods, MLR and LS. The proposed method included two prediction types, multi-point prediction and single-point prediction. WPP is tested by applying different models such as autoregressive moving average (ARMA), autoregressive integrated moving average (ARIMA) and artificial neural network (ANN). By comparing results of the above models, the validity of the proposed hybrid model is confirmed in terms of error and correlation coefficient. Comparison of results confirmed that the proposed method works effectively. Additional, forecasting errors were also computed and compared, to improve understanding of how to depict highly variable WPP and the correlations between actual and predicted wind power.

Ultra-low-frequency dust-electromagnetic modes in self-gravitating magnetized dusty plasmas

International Nuclear Information System (INIS)

Banerjee, A.K.; Alam, M.N.; Mamun, A.A.

2001-01-01

Obliquely propagating ultra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized, two fluid dusty plasma system have been investigated. Two special cases, namely, dust-Alfven mode propagating parallel to the external magnetic field and dust- magnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that in parallel propagating dust-Alfven mode these effects play no role, but in obliquely propagating dust-Alfven mode or perpendicular propagating dust-magnetosonic mode the effect of self-gravitational field plays destabilizing role whereas the effect of dust/ion fluid temperature plays stabilizing role. (author)

Low power interface IC's for electrostatic energy harvesting applications

Science.gov (United States)

Kempitiya, Asantha

interest where the storage capacitor can be optimized to produce almost 70% of the ideal power taken as the power harvested with synchronous converters when neglecting the power consumption associated with synchronizing control circuitry. Theoretical predictions are confirmed by measurements on an asynchronous EHC implemented with a macro-scale electrostatic converter prototype. Based on the preceding analysis, the design of a novel ultra low power electrostatic integrated energy harvesting circuit is proposed for efficient harvesting of mechanical energy. The fundamental challenges of designing reliable low power sensing circuits for charge constrained electrostatic energy harvesters with capacity to self power its controller and driver stages are addressed. Experimental results are presented for a controller design implemented in AMI 0.7muM high voltage CMOS process using a macro-scale electrostatic converter prototype. The EHC produces 1.126muW for a power investment of 417nW with combined conduction and controller losses of 450nW which is a 20-30% improvement compared to prior art on electrostatic EHCs operating under charge constrain. Inherently dual plate variable capacitors harvest energy only during half of the mechanical cycle with the other half unutilized for energy conversion. To harvest mechanical energy over the complete mechanical vibration cycle, a low power energy harvesting circuit (EHC) that performs charge constrained synchronous energy conversion on a tri-plate variable capacitor for maximizing energy conversion is proposed. The tri-plate macro electrostatic generator with capacitor variation of 405pF to 1.15nF and 405pF to 1.07nF on two complementary adjacent capacitors is fabricated and used in the characterization of the designed EHC. The integrated circuit fabricated in AMI 0.7muM high voltage CMOS process, produces a total output power of 497nW to a 10muF reservoir capacitor from a 98Hz vibration signal. In summary, the thesis lays out the

Developing Low-Power Transceiver Technologies for In Situ Communication Applications

Science.gov (United States)

Lay, N.; Cheetham, C.; Mojaradi, H.; Neal, J.

2001-07-01

For future deep-space missions, significant reductions in the mass and power requirements for short-range telecommunication systems will be critical in enabling a wide variety of new mission concepts. These possibilities include penetrators, gliders, miniature rovers, balloons, and sensor networks. The recent development activity reported in this article has focused on the design of ultra-low-mass and -power transceiver systems and subsystems suitable for operation in a flight environment. Under these efforts, the basic functionality of the transceiver has been targeted towards a Mars microprobe communications scenario. However, the overall transceiver architecture is well suited to any short- or medium-range application where a remote probe will aperiodically communicate with a base station, possibly an orbiter, for the eventual purpose of relaying science information back to Earth. Additionally, elements of the radio architecture can be applied in situations involving surface-to-surface communications, thereby enabling different mission communications topologies. Through a system analysis of these channels, both the applicability and benefit of very low power communications will be quantitatively addressed.

Low-power laser therapy for carpal tunnel syndrome: effective optical power

Directory of Open Access Journals (Sweden)

Yan Chen

2016-01-01

Full Text Available Low-power laser therapy has been used for the non-surgical treatment of mild to moderate carpal tunnel syndrome, although its efficacy has been a long-standing controversy. The laser parameters in low-power laser therapy are closely related to the laser effect on human tissue. To evaluate the efficacy of low-power laser therapy, laser parameters should be accurately measured and controlled, which has been ignored in previous clinical trials. Here, we report the measurement of the effective optical power of low-power laser therapy for carpal tunnel syndrome. By monitoring the backside reflection and scattering laser power from human skin at the wrist, the effective laser power can be inferred. Using clinical measurements from 30 cases, we found that the effective laser power differed significantly among cases, with the measured laser reflection coefficient ranging from 1.8% to 54%. The reflection coefficient for 36.7% of these 30 cases was in the range of 10–20%, but for 16.7% of cases, it was higher than 40%. Consequently, monitoring the effective optical power during laser irradiation is necessary for the laser therapy of carpal tunnel syndrome.

Self-powered neutron flux detector

International Nuclear Information System (INIS)

Kroon, J.

1979-01-01

A self-powered neutron flux detector having an emitter electrode, at least a major portion of which is, 95 Mo encased in a tubular collector electrode and separated therefrom by dielectric material. The 95 Mo emitter electrode has experimentally shown a 98% prompt response, is primarily sensitive to neutron flux, has adequate sensitivity and has low burn up. Preferably the emitter electrode is molybdenum which has been enriched 75% to 99% by weight with 95 Mo

Implantable Self-Powered Low-Level Laser Cure System for Mouse Embryonic Osteoblasts' Proliferation and Differentiation.

Science.gov (United States)

Tang, Wei; Tian, Jingjing; Zheng, Qiang; Yan, Lin; Wang, Jiangxue; Li, Zhou; Wang, Zhong Lin

2015-08-25

Bone remodeling or orthodontic treatment is usually a long-term process. It is highly desirable to speed up the process for effective medical treatment. In this work, a self-powered low-level laser cure system for osteogenesis is developed using the power generated by the triboelectric nanogenerator. It is found that the system significantly accelerated the mouse embryonic osteoblasts' proliferation and differentiation, which is essential for bone and tooth healing. The system is further demonstrated to be driven by a living creature's motions, such as human walking or a mouse's breathing, suggesting its practical use as a portable or implantable clinical cure for bone remodeling or orthodontic treatment.

Record power, ultra-broadband supercontinuum source based on highly GeO2 doped silica fiber

DEFF Research Database (Denmark)

Jain, Deepak; Sidharthan, R.; Moselund, Peter M.

2016-01-01

the potential of germania based photonic crystal fiber or a step-index fiber supercontinuum source for high power ultra-broad band emission being by pumped a 1060 nm or a 1550 nm laser source. To the best of our knowledge, this is the record power, ultra-broadband, and all-fiberized supercontinuum light source...... based on silica and germania fiber ever demonstrated to the date. (C) 2016 Optical Society of America......We demonstrate highly germania doped fibers for mid-infrared supercontinuum generation. Experiments ensure a highest output power of 1.44 W for a broadest spectrum from 700 nm to 3200 nm and 6.4 W for 800 nm to 2700 nm from these fibers, while being pumped by a broadband Erbium-Ytterbium doped...

Dual-functional on-chip AlGaAs/GaAs Schottky diode for RF power detection and low-power rectenna applications.

Science.gov (United States)

Hashim, Abdul Manaf; Mustafa, Farahiyah; Rahman, Shaharin Fadzli Abd; Rahman, Abdul Rahim Abdul

2011-01-01

A Schottky diode has been designed and fabricated on an n-AlGaAs/GaAs high-electron-mobility-transistor (HEMT) structure. Current-voltage (I-V) measurements show good device rectification, with a Schottky barrier height of 0.4349 eV for Ni/Au metallization. The differences between the Schottky barrier height and the theoretical value (1.443 eV) are due to the fabrication process and smaller contact area. The RF signals up to 1 GHz are rectified well by the fabricated Schottky diode and a stable DC output voltage is obtained. The increment ratio of output voltage vs input power is 0.2 V/dBm for all tested frequencies, which is considered good enough for RF power detection. Power conversion efficiency up to 50% is obtained at frequency of 1 GHz and input power of 20 dBm with series connection between diode and load, which also shows the device's good potential as a rectenna device with further improvement. The fabricated n-AlGaAs/GaAs Schottky diode thus provides a conduit for breakthrough designs for RF power detectors, as well as ultra-low power on-chip rectenna device technology to be integrated in nanosystems.

Power generation using photovoltaic induction in an isolated power network

International Nuclear Information System (INIS)

Kalantar, M.; Jiang, J.

2001-01-01

Owing to increased emphasis on renewable resources, the development of suitable isolated power generators driven by energy sources, the development of suitable isolated power generators driven by energy sources such as photovoltaic, wind, small hydroelectric, biogas and etc. has recently assumed greater significance. A single phase capacitor self excited induction generator has emerged as a suitable candidate of isolated power sources. This paper presents performance analysis of a single phase self-excited induction generator driven by photovoltaic (P V) system for low power isolated stand-alone applications. A single phase induction machine can work as a self-excited induction generator when its rotor is driven at suitable speed by an photovoltaic powered do motor. Its excitation is provided by connecting a single phase capacitor bank at a stator terminals. Either to augment grid power or to get uninterrupted power during grid failure stand-alone low capacity ac generators are used. These are driven by photovoltaic, wind power or I C engines using kerosene, diesel, petrol or biogas as fuel. Self-excitation with capacitors at the stator terminals of the stator terminals of the induction machines is well demonstrated experimentally on a P V powered dc motor-induction machine set. The parameters and the excitation requirements of the induction machine run in self-excited induction generator mode are determined. The effects of variations in prime mover speed,terminal capacitance and load power factor on the machine terminal voltage are studied

Hybrid nanogenerators for low frequency vibration energy harvesting and self-powered wireless locating

Science.gov (United States)

Yuan, Ying; Zhang, Hulin; Wang, Jie; Xie, Yuhang; Khan, Saeed Ahmed; Jin, Long; Yan, Zhuocheng; Huang, Long; Pan, Taisong; Yang, Weiqing; Lin, Yuan

2018-01-01

Hybrid energy harvesters based on different physical effects is fascinating, but a rational design for multiple energy harvesting is challenging. In this work, a spring-magnet oscillator-based triboelectric-electromagnetic generator (EMG) with a solar cell cap is proposed. A power was produced by a triboelectric nanogenerator (TENG) and an EMG independently or simultaneously by using a shared spring-magnet oscillator. The oscillator configuration enables versatile energy harvesting with the excellent size scalability and self-packaged structure which can perform well at low frequency ranging from 3.5 to 5 Hz. The solar cell cap mounted above the oscillator can harvest solar energy. Under vibrations at the frequency of 4 Hz, the TENG and the EMG produced maximum output power of 5.46 nW cm-3 and 378.79 μW cm-3, respectively. The generated electricity by the hybrid nanogenerator can be stored in a capacitor or Li-ion battery, which is capable of powering a wireless locator for real-time locating data reporting to a personal cell phone. The light-weight and handy hybrid nanogenerator can directly light a caution light or play as a portable flashlight by shaking hands at night.

Self-Powered Sun Sensor Microsystems

NARCIS (Netherlands)

Wu, H.; Emadi, A.; Graaf, G. de; Leijtens, J.A.P.; Wolffenbuttel, R.F.

2009-01-01

An analog sun sensor has been designed based on shade profile proportional to the angle of incidence of incoming light projected onto a 2×2 array of photodiodes. This concept enables an autonomous self-powered optical system with two the main functions (electrical power generation for the amplifier

Characterization and design of a low-power wireless power delivery system

Science.gov (United States)

Falkenstein, Erez Avigdor

There is an increased demand for wireless sensors for data gathering and transmission where running wires to power a device or changing/charging batteries is difficult. Often the data is gathered at locations that are difficult to access, that need to be covert, and/or where the sensors cannot be easily maintained. Some examples are implanted sensors for medical diagnostics and therapy, structural monitoring sensors, sensors inside hazardous manufacturing or other hazardous environments, etc. For any low power sensor that operates at a low duty cycle, and in an environment with low levels of light or vibration, RF wireless powering offers the potential for maintenance-free operation. The thesis focuses on a design methodology for low-power non-directional far-field wireless powering. The power receiver consists of one or more antennae which receive plane waves transmitted by the powering source, and deliver the RF power to a rectifying element. The resulting DC power is optimally transferred to the electronic application via a power management circuit. The powering is independent of the electronic application which can include wireless transmission of sensor data. The design and implementation of an integrated rectifier-antenna at low incident power densities (from 25--200 muW/cm2) is presented. Nonlinear source-pull measurements and harmonic balance simulations are used for finding the optimal rectifying device RF and DC impedances for efficient rectification. Experimental results show that an antenna design with a specific complex impedance reaches the highest rectification efficiency. Several examples of the design methodology will be shown. In specific, characterization of a rectifying patch antenna at frequency of 2.45GHz will be detailed, with an optimal RF impedance of 137+j149O and an optimal DC load of 365O resulting in RF to DC conversion efficiency of 63% for the rectifier alone and 56% for the total rectifying antenna.

Ultra-Low Power Memory Design in Scaled Technology Nodes

DEFF Research Database (Denmark)

Zeinali, Behzad

that the proposed SRAM reduces access time and leakage current by 40% and 20%, respectively, compared to the standard 8T-SRAM cell without any degradation in read and write margins. The second solution is an asymmetric Schottky barrier device, which can mitigate the read–write conflict of the 6T-SRAM cell in scaled...... technology nodes i.e. sub-50 nm. The 6T-SRAM designed based on the proposed device shows 18% leakage reduction and 54%, 6.6% and 3.1X improvement in read margin, write margin and write time, respectively, compared to the conventional 6T-SRAM cell. To address the standby power issue of SRAMs in scaled...... technology nodes, this thesis also investigates emerging non-volatile spintronics memories. In this respect, STT-MRAMs and SOT-MRAMs are studied and their design challenges are explored. To improve the read performance of STT-MRAMs, a novel non-destructive self-reference sensing scheme is proposed enabling...

Low-Power Wireless Sensor Network Infrastructures

DEFF Research Database (Denmark)

Hansen, Morten Tranberg

Advancements in wireless communication and electronics improving form factor and hardware capabilities has expanded the applicability of wireless sensor networks. Despite these advancements, devices are still limited in terms of energy which creates the need for duty-cycling and low-power protocols...... peripherals need to by duty-cycled and the low-power wireless radios are severely influenced by the environmental effects causing bursty and unreliable wireless channels. This dissertation presents a communication stack providing services for low-power communication, secure communication, data collection......, and network management which enables construction of low-power wireless sensor network applications. More specifically, these services are designed with the extreme low-power scenarios of the SensoByg project in mind and are implemented as follows. First, low-power communication is implemented with Auto...

Research on self-powered detectors for gamma-ray monitoring

International Nuclear Information System (INIS)

Cho, S.W.; Lee, Y.J.

1984-01-01

Self-powered neutron detectors are used extensively in power reactors both for flux mapping and for power control and over-power protection, because of their small size, ruggedness and simplicity. But they have a few disadvantages such as high burn-up rate and background signal produced by the gamma-rays from the reactor itself. In order to overcome these disadvantages and to achieve a better understanding of gamma-ray effects of self-power detectors, a new type of self-powered detectors was designed and fabricated by the author,and experiments have carried out in the 10kCi sup(60)Co gamma irradiation facility in Korea Advanced Energy Research Institute. The configuration of the new type detectors is not of coaxial type but of paralled plate in order to obtain directional effects of gamma-ray incidence. Detector materials and dimensions are so chosen that the output current signal is large enough to be detected using some commercial measuring divice even at low dose rate and the contribution of the lead cable to the total signal is negligibly small. The results are 1)sensitivity is depended primarily on the materials of the insulator, 2)output signal has a good linearity to gamma dose rate, 3) response of detectors is prompt, but not perfect, 4) critical thickness for satusation of the output current is thinner than the range of photoelectron in the materials. (Author)

Research on self-powered detectors for gamma-ray monitoring

International Nuclear Information System (INIS)

Cho, S.W.

1983-01-01

Self-powered neutron detectors are used extensively in power reactors both for flux mapping and for power control and over-power protection, because of their small size, ruggedness and simplicity. But they have a few disadvantages such as high burn-up rate and background signal produced by the gamma-rays from the reactor itself. In order to overcome these disadvantages and to achieve a better understanding of gamma-ray effects of self-powered detectors, a new type of self-powered detectors was designed and fabricated by the author, and experiments have been carried out in the 10kCi sup(60)Co gamma irradiation facility in Korea Advanced Energy Research Institute. The configuration of the new type detectors is not of coaxial type but of paralled plate in order to obtain directional effects of gamma-ray incidence. Detector materials and dimensions are so chosen that the output current signal is large enough to be detected using some commercial measuring divice even at low dose rate and the contribution of the lead cable to the totel signal is negligibly small. The results are 1) sensitivity is depended primarily on the materials of the insulator, 2) output signal has a good linearity to gamma dose rate, 3) response of detectors is prompt, but not perfect, 4) critical thickness for satusation of the output current is thinner than the range of photoelectron in the materials. (Author) πT

Cost-effectiveness of low-power nuclear power plants

International Nuclear Information System (INIS)

Mitenkov, F.M.; Vostokov, V.S.; Drozhkin, V.N.; Samoilov, O.B.

1994-01-01

Many potential consumers of electricity and heat, consuming several thousands of kilowatts (up to 10-15 MW), have now been identified. This is significant primarily for regions far from power grids and other centralized sources of energy, such as, for example, Yakutiya, Northeastern Siberia, and elsewhere. These consumers are now supplied with fossil fuel, which is often difficult and expensive to deliver. For this reason it is very important to develop low-power nuclear power plants for remote regions

Ultra-low power transmitter for encoding non-MR signals in Magnetic Resonance (MR) recordings

DEFF Research Database (Denmark)

Petersen, Jan Raagaard; Pedersen, Jan Ole; Zhurbenko, Vitaliy

collection of data from non-MRI sensors. The transmitter consumes only 1.3mW while transmitting 2.7µW at 120MHz with high frequency stability. The presented design is useful in low power applications requiring high frequency stability and is intended for wireless transmission of non-MR signal recordings......Advancing Magnetic Resonance Imaging (MRI) technology requires integration of the MRI scanners with sensors and systems for monitoring various non-MRI signals. In this paper, we present design and integration of a low power AM radio transmitter into a 3T MRI scanner, which can be used for efficient...

Wearable and Implantable Mechanical Energy Harvesters for Self-Powered Biomedical Systems.

Science.gov (United States)

Hinchet, Ronan; Kim, Sang-Woo

2015-08-25

In this issue of ACS Nano, Tang et al. investigate the ability of a triboelectric nanogenerator (TENG) to self-power a low-level laser cure system for osteogenesis by studying the efficiency of a bone remodeling laser treatment that is powered by a skin-patch-like TENG instead of a battery. We outline this field by highlighting the motivations for self-powered biomedical systems and by discussing recent progress in nanogenerators. We note the overlap between biomedical devices and TENGs and their dawning synergy, and we highlight key prospects for future developments. Biomedical systems should be more autonomous. This advance could improve their body integration and fields of action, leading to new medical diagnostics and treatments. However, future self-powered biomedical systems will need to be more flexible, biocompatible, and biodegradable. These advances hold the promise of enabling new smart autonomous biomedical systems and contributing significantly to the Internet of Things.

Self-powered radiation detector

International Nuclear Information System (INIS)

Goldstein, N.P.; Todt, W.H.

1979-01-01

Self-powered gamma radiation detector composed of a conducting emitter surrounded by an insulating medium and a conducting tubular collector, the emitter being a hollow tube containing an electrical insulator [fr

Self-oscillating resonant power converter

DEFF Research Database (Denmark)

2014-01-01

The present invention relates to resonant power converters and inverters comprising a self-oscillating feedback loop coupled from a switch output to a control input of a switching network comprising one or more semiconductor switches. The self-oscillating feedback loop sets a switching frequency...... of the power converter and comprises a first intrinsic switch capacitance coupled between a switch output and a control input of the switching network and a first inductor. The first inductor is coupled in-between a first bias voltage source and the control input of the switching network and has...... a substantially fixed inductance. The first bias voltage source is configured to generate an adjustable bias voltage applied to the first inductor. The output voltage of the power converter is controlled in a flexible and rapid manner by controlling the adjustable bias voltage....

Low Power/Low Voltage Interface Circuitry for Capacitive Sensors

DEFF Research Database (Denmark)

Furst, Claus Efdmann

This thesis focuses mainly on low power/low voltage interface circuits, implemented in CMOS, for capacitive sensors. A brief discussion of demands and possibilities for analog signal processing in the future is presented. Techniques for low power design is presented. This is done by analyzing power...... power consumption. It is shown that the Sigma-Delta modulator is advantageous when embedded in a feedback loop with a mechanical sensor. Here a micro mechanical capacitive microphone. Feedback and detection circuitry for a capacitive microphone is presented. Practical implementations of low power....../low voltage interface circuitry is presented. It is demonstrated that an amplifier optimized for a capacitive microphone implemented in a standard 0.7 micron CMOS technology competes well with a traditional JFET amplifier. Furthermore a low power/low voltage 3rd order Sigma-Delta modulator is presented...

A Self-Powered Insole for Human Motion Recognition

Directory of Open Access Journals (Sweden)

Yingzhou Han

2016-09-01

Full Text Available Biomechanical energy harvesting is a feasible solution for powering wearable sensors by directly driving electronics or acting as wearable self-powered sensors. A wearable insole that not only can harvest energy from foot pressure during walking but also can serve as a self-powered human motion recognition sensor is reported. The insole is designed as a sandwich structure consisting of two wavy silica gel film separated by a flexible piezoelectric foil stave, which has higher performance compared with conventional piezoelectric harvesters with cantilever structure. The energy harvesting insole is capable of driving some common electronics by scavenging energy from human walking. Moreover, it can be used to recognize human motion as the waveforms it generates change when people are in different locomotion modes. It is demonstrated that different types of human motion such as walking and running are clearly classified by the insole without any external power source. This work not only expands the applications of piezoelectric energy harvesters for wearable power supplies and self-powered sensors, but also provides possible approaches for wearable self-powered human motion monitoring that is of great importance in many fields such as rehabilitation and sports science.

Rhodium self-powered neutron detector's lifetime for korean standard nuclear power plants

International Nuclear Information System (INIS)

Yoo, Choon Sung; Kim, Byoung Chul; Park, Jong Ho; Fero, Arnold H.; Anderson, S. L.

2005-01-01

A method to estimate the relative sensitivity of a self-powered rhodium detector for an upcoming cycle is developed by combining the rhodium depletion data from a nuclear design with the site measurement data. This method can be used both by nuclear power plant designers and by site staffs of Korean standard nuclear power plants for determining which rhodium detectors should be replaced during overhauls

Dual-Functional On-Chip AlGaAs/GaAs Schottky Diode for RF Power Detection and Low-Power Rectenna Applications

Directory of Open Access Journals (Sweden)

Abdul Manaf Hashim

2011-08-01

Full Text Available A Schottky diode has been designed and fabricated on an n-AlGaAs/GaAs high-electron-mobility-transistor (HEMT structure. Current-voltage (I-V measurements show good device rectification, with a Schottky barrier height of 0.4349 eV for Ni/Au metallization. The differences between the Schottky barrier height and the theoretical value (1.443 eV are due to the fabrication process and smaller contact area. The RF signals up to 1 GHz are rectified well by the fabricated Schottky diode and a stable DC output voltage is obtained. The increment ratio of output voltage vs input power is 0.2 V/dBm for all tested frequencies, which is considered good enough for RF power detection. Power conversion efficiency up to 50% is obtained at frequency of 1 GHz and input power of 20 dBm with series connection between diode and load, which also shows the device’s good potential as a rectenna device with further improvement. The fabricated n-AlGaAs/GaAs Schottky diode thus provides a conduit for breakthrough designs for RF power detectors, as well as ultra-low power on-chip rectenna device technology to be integrated in nanosystems.

Self powered neutron detectors

International Nuclear Information System (INIS)

Passe, J.; Petitcolas, H.; Verdant, R.

1975-01-01

The self-powered neutron detectors (SPND) enable to measure continuously high fluxes of thermal neutrons. They are particularly suitable for power reactor cores because of their robustness. Description of two kinds of SPND's characterized by the electrical current production way is given here: the first SPND's which present a V, Ag or Rh emitter are sensitive enough but they offer a few minute delay time: the second SPND's which are depending on the gamma activation have a short delay time. The emitter is made of Co or Pt. In any case, the signal is linear with reaction rates. Finally, the applications are briefly repeated here: irradiation facility monitor in research reactors, and flux map and space instability control in power reactors [fr

Novel partial-subsidence tower-type boiler design in an ultra-supercritical power plant

International Nuclear Information System (INIS)

Xu, Gang; Xu, Cheng; Yang, Yongping; Fang, Yaxiong; Zhou, Luyao; Zhang, Kai

2014-01-01

Highlights: • The two-pass type and tower-type boilers were compared. • A novel partial-subsidence tower-type boiler design was proposed. • Thermodynamic and economic analyses were quantitatively conducted. • The application of the partial-subsidence boiler to a 700 °C stage unit was further analyzed. - Abstract: An increasing number of tower-type boilers have been applied to ultra-supercritical power plants because of the simple design of the membrane walls and the smooth increase in temperature of such boilers. Nevertheless, the significant height and long steam pipelines of this boiler type will expand the power plant investment cost and increase steam-side pressure losses, especially for higher parameters units requiring high costs of nickel-based alloy materials. Thus, a novel partial-subsidence tower-type boiler design was proposed. In this boiler type, nearly 1/2–2/3 of the boiler height was embedded underground to reduce the height of the boiler and the length of the steam pipelines significantly. Thermodynamic and economic analyses were conducted on a state-of-the-art 1000 MW ultra-supercritical power plant and a prospective 700 °C-stage double reheat power plant. Results showed that the proposed tower-type boiler design could result in a 0.1% point increase in net efficiency and a $0.56/MW h reduction in the cost of electricity in a 1000 MW power plant. This economic benefit was enhanced for power plants with higher steam parameters and larger capacity. The concept of the proposed boiler design may provide a promising method for tower-type boiler applications, especially in new-generation double reheat plants with higher parameters

Ultra low-power biomedical signal processing : An analog wavelet filter approach for pacemakers

NARCIS (Netherlands)

Pavlík Haddad, S.A.

2006-01-01

The purpose of this thesis is to describe novel signal processing methodologies and analog integrated circuit techniques for low-power biomedical systems. Physiological signals, such as the electrocardiogram (ECG), the electroencephalogram (EEG) and the electromyogram (EMG) are mostly

Low-power low-noise analog circuits for on-focal-plane signal processing of infrared sensors

Science.gov (United States)

Pain, Bedabrata; Mendis, Sunetra K.; Schober, Robert C.; Nixon, Robert H.; Fossum, Eric R.

1993-10-01

On-focal-plane signal processing circuits for enhancement of IR imager performance are presented. To enable the detection of high background IR images, an in-pixel current-mode background suppression scheme is presented. The background suppression circuit consists of a current memory placed in the feedback loop of a CTIA and is designed for a thousand-fold suppression of the background flux, thereby easing circuit design constraints, and assuring BLIP operation even with detectors having large response non-uniformities. For improving the performance of low-background IR imagers, an on-chip column-parallel analog-to-digital converter (ADC) is presented. The design of a 10-bit ADC with 50 micrometers pitch and based on sigma-delta ((Sigma) -(Delta) ) modulation is presented. A novel IR imager readout technique featuring photoelectron counting in the unit cell is presented for ultra-low background applications. The output of the unit cell is a digital word corresponding to the incident flux density and the readout is noise free. The design of low-power (noise, high-gain (> 100,000), small real estate (60 micrometers pitch) self-biased CMOS amplifiers required for photon counting are presented.

Sensitivity Calculation of Vanadium Self-Powered Neutron Detector

International Nuclear Information System (INIS)

Cha, Kyoon Ho

2011-01-01

Self-powered neutron detector (SPND) is being widely used to monitor the reactor core of the nuclear power plants. The SPND contains a neutron-sensitive metallic emitter surrounded by a ceramic insulator. Currently, the rhodium SPND has been used in many nuclear power plants. The lifetime of rhodium is too short (about 3∼5 years) to operate the nuclear power plant economically. The vanadium (V) SPND is also primarily sensitive to neutrons like rhodium, but is a somewhat slower reaction time as that of a rhodium SPND. The benefit of vanadium over rhodium is its low depletion rate, which is a factor of 7 times less than that of rhodium. For this reason, a vanadium SPND has been being developed to replace the rhodium SPND which is used in OPR1000. Some Monte Carlo simulations were accomplished to calculate the initial sensitivity of vanadium emitter material and alumina (Al 2 O 3 ) insulator with a cylindrical geometry. An MCNP-X code was used to simulate some factors (neutron self shielding factor and electron escape probability from the emitter) necessary to calculate the sensitivity of vanadium detector. The simulation results were compared with some theoretical and experimental values. The method presented here can be used to analyze the optimum design of the vanadium SPND

Self-powered in-core neutron detector assembly with uniform perturbation characteristics

International Nuclear Information System (INIS)

Todt, W.H.; Playfoot, K.C.

1979-01-01

Disclosed is a self-powered in-core neutron detector assembly in which a plurality of longitudinally extending self-powered detectors have neutron responsive active portions spaced along a longitudinal path. A low neutron absorptive extension extends from the active portions of the spaced active portions of the detectors in symmetrical longitudinal relationship with the spaced active detector portions of each succeeding detector. The detector extension terminates with the detector assembly to provide a uniform perturbation characteristic over the entire assembly length

Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to 'Power Poses'.

Science.gov (United States)

Golec de Zavala, Agnieszka; Lantos, Dorottya; Bowden, Deborah

2017-01-01

Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of 'power poses,' which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010). The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to 'high power' and 'low power' poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body ( n = 19), two standing yoga poses with covered front of the body ( n = 22), two expansive, high power poses ( n = 21), or two constrictive, low power poses ( n = 20) for 1-min each. The results showed that yoga poses in comparison to 'power poses' increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses' association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min.

Power Conversion Efficiency of AlGaAs/GaAs Schottky Diode for Low-Power On-Chip Rectenna Device Application

International Nuclear Information System (INIS)

Mustafa, Farahiyah; Hashim, Abdul Manaf; Rahman, Shaharin Fadzli Abd; Osman, Mohd Nizam

2011-01-01

A Schottky diode has been designed and fabricated on n-AlGaAs/GaAs high-electron-mobility-transistor (HEMT) structure. Current-voltage (I-V) measurements show good device rectification with a Schottky barrier height of 0.4349 eV for Ni/Au metallization. The differences of Schottky barrier height from theoretical value are due to the fabrication process and smaller contact area. The RF signals up to 1 GHz are well rectified by the fabricated Schottky diodes and stable DC output voltage is obtained. Power conversion efficiency up to 50% is obtained at 1 GHz with series connection between diode and load. The fabricated the n-AlGaAs/GaAs Schottky diode provide conduit for breakthrough designs for ultra-low power on-chip rectenna device technology to be integrated in nanosystems.

Power generation in the 21st century: ultra efficient, low emission plant

International Nuclear Information System (INIS)

Kozlowski, R.H.

1999-01-01

The ready availability of energy at an economical price is major factor affecting the success of manufacturing industry, upon which the general well-being and the standard of living of the population depend. The provision of sufficient supplies of energy, bearing in mind the large increase in world population expected over the coming decades, presents a considerable economic and technological challenge to the power manufactures. The introduction of increasingly stringent emission regulations to safeguard health and preserve the environment for future generations increases the pressure for the development of environmentally benign power generating plants with low NO, SO and CO emission. For plant designers and manufacturers, materials suppliers and component manufacturers, the business opportunities and technical challenges that will arise through the increased world demand for electricity are significant (author)

Triboelectric Nanogenerator Enabled Body Sensor Network for Self-Powered Human Heart-Rate Monitoring.

Science.gov (United States)

Lin, Zhiming; Chen, Jun; Li, Xiaoshi; Zhou, Zhihao; Meng, Keyu; Wei, Wei; Yang, Jin; Wang, Zhong Lin

2017-09-26

Heart-rate monitoring plays a critical role in personal healthcare management. A low-cost, noninvasive, and user-friendly heart-rate monitoring system is highly desirable. Here, a self-powered wireless body sensor network (BSN) system is developed for heart-rate monitoring via integration of a downy-structure-based triboelectric nanogenerator (D-TENG), a power management circuit, a heart-rate sensor, a signal processing unit, and Bluetooth module for wireless data transmission. By converting the inertia energy of human walking into electric power, a maximum power of 2.28 mW with total conversion efficiency of 57.9% was delivered at low operation frequency, which is capable of immediately and sustainably driving the highly integrated BSN system. The acquired heart-rate signal by the sensor would be processed in the signal process circuit, sent to an external device via the Bluetooth module, and displayed on a personal cell phone in a real-time manner. Moreover, by combining a TENG-based generator and a TENG-based sensor, an all-TENG-based wireless BSN system was developed, realizing continuous and self-powered heart-rate monitoring. This work presents a potential method for personal heart-rate monitoring, featured as being self-powered, cost-effective, noninvasive, and user-friendly.

LOW-POWER AC LOADS AND ELECTRICAL POWER QUALITY

Directory of Open Access Journals (Sweden)

EPURE S.

2016-12-01

Full Text Available This paper deals with experimental study and numerical simulation of single phase AC low power loads: artificial light sources, personal computers, refrigeration units, air conditioning units and TV receivers. These loads are in such large numbers that represents the main source of disturbances (harmonic current, reactive power and unbalanced three-phase network. The obtained simulation models, verified by comparison with experimental results may be used in larger simulation models for testing and sizing the optimum parameters of active power filters. Models can also be used to study the interactions between grid elements and various loads or situations.

Medlay: A Reconfigurable Micro-Power Management to Investigate Self-Powered Systems

Directory of Open Access Journals (Sweden)

Jan Kokert

2018-01-01

Full Text Available In self-powered microsystems, a power management is essential to extract, transfer and regulate power from energy harvesting sources to loads such as sensors. The challenge is to consider all of the different structures and components available and build the optimal power management on a microscale. The purpose of this paper is to streamline the design process by creating a novel reconfigurable testbed called Medlay. First, we propose a uniform interface for management functions e.g., power conversion, energy storing and power routing. This interface results in a clear layout because power and status pins are strictly separated, and inputs and outputs have fixed positions. Medlay is the ready-to-use and open-hardware platform based on the interface. It consists of a base board and small modules incorporating e.g., dc-dc converters, power switches and supercapacitors. Measurements confirm that Medlay represents a system on one circuit board, as parasitic effects of the interconnections are negligible. The versatility regarding different setups on the testbed is determined to over 250,000 combinations by layout graph grammar. Lastly, we underline the applicability by recreating three state-of-the-art systems with the testbed. In conclusion, Medlay facilitates building and testing power management in a very compact, clear and extensible fashion.

Microbial fuel cells as power supply of a low-power temperature sensor

Science.gov (United States)

Khaled, Firas; Ondel, Olivier; Allard, Bruno

2016-02-01

Microbial fuel cells (MFCs) show great promise as a concomitant process for water treatment and as renewable energy sources for environmental sensors. The small energy produced by MFCs and the low output voltage limit the applications of MFCs. Specific converter topologies are required to step-up the output voltage of a MFC. A Power Management Unit (PMU) is proposed for operation at low input voltage and at very low power in a completely autonomous way to capture energy from MFCs with the highest possible efficiency. The application of sensors for monitoring systems in remote locations is an important approach. MFCs could be an alternative energy source in this case. Powering a sensor with MFCs may prove the fact that wastewater may be partly turned into renewable energy for realistic applications. The Power Management Unit is demonstrated for 3.6 V output voltage at 1 mW continuous power, based on a low-cost 0.7-L MFC. A temperature sensor may operate continuously on 2-MFCs in continuous flow mode. A flyback converter under discontinuous conduction mode is also tested to power the sensor. One continuously fed MFC was able to efficiently and continuously power the sensor.

Probabilistic safety assessments of nuclear power plants for low power and shutdown modes

International Nuclear Information System (INIS)

2000-03-01

Within the past several years the results of nuclear power plant operating experience and performance of probabilistic safety assessments (PSAs) for low power and shutdown operating modes have revealed that the risk from operating modes other than full power may contribute significantly to the overall risk from plant operations. These early results have led to an increased focus on safety during low power and shutdown operating modes and to an increased interest of many plant operators in performing shutdown and low power PSAs. This publication was developed to provide guidance and insights on the performance of PSA for shutdown and low power operating modes. The preparation of this publication was initiated in 1994. Two technical consultants meetings were conducted in 1994 and one in February 1999 in support of the development of this report

Self powered neutron detectors

International Nuclear Information System (INIS)

Gopalan, C.S.; Ramachandra Rao, M.N.; Ingale, A.D.

1976-01-01

Two types of self powered neutron detectors used for in-core flux measurements are described. The characteristics of the various detectors, with emitters Rh, V, Co, Py are presented. Details about the fabrication of these detectors are given. (A.K.)

CMOS circuits for electromagnetic vibration transducers interfaces for ultra-low voltage energy harvesting

CERN Document Server

Maurath, Dominic

2015-01-01

Chip-integrated power management solutions are a must for ultra-low power systems. This enables not only the optimization of innovative sensor applications. It is also essential for integration and miniaturization of energy harvesting supply strategies of portable and autonomous monitoring systems. The book particularly addresses interfaces for energy harvesting, which are the key element to connect micro transducers to energy storage elements. Main features of the book are: - A comprehensive technology and application review, basics on transducer mechanics, fundamental circuit and control design, prototyping and testing, up to sensor system supply and applications. - Novel interfacing concepts - including active rectifiers, MPPT methods for efficient tracking of DC as well as AC sources, and a fully-integrated charge pump for efficient maximum AC power tracking at sub-100µW ultra-low power levels. The chips achieve one of widest presented operational voltage range in standard CMOS technology: 0.44V to over...

An optimized junctionless GAA MOSFET design based on multi-objective computation for high-performance ultra-low power devices

International Nuclear Information System (INIS)

Bendib, T.; Djeffal, F.; Meguellati, M.

2014-01-01

An analytical investigation has been proposed to study the subthreshold behavior of junctionless gates all around (JLGAA) MOSFET for nanoscale CMOS analog applications. Based on 2-D analytical analysis, a new subthreshold swing model for short-channel JLGAA MOSFETs is developed. The analysis has been used to calculate the subthreshold swing and to compare the performance of the investigated design and conventional GAA MOSFET, where the comparison of device architectures shows that the JLGAA MOSFET exhibits a superior performance with respect to the conventional inversion-mode GAA MOSFET in terms of the fabrication process and electrical behavior in the subthreshold domain. The analytical models have been validated by 2-D numerical simulations. The proposed analytical models are used to formulate the objectives functions. The overall objective function is formulated by means of a weighted sum approach to search the optimal electrical and dimensional device parameters in order to obtain the better scaling capability and the electrical performance of the device for ultra-low power applications. (semiconductor devices)

High Efficiency Power Converter for Low Voltage High Power Applications

DEFF Research Database (Denmark)

Nymand, Morten

The topic of this thesis is the design of high efficiency power electronic dc-to-dc converters for high-power, low-input-voltage to high-output-voltage applications. These converters are increasingly required for emerging sustainable energy systems such as fuel cell, battery or photo voltaic based......, and remote power generation for light towers, camper vans, boats, beacons, and buoys etc. A review of current state-of-the-art is presented. The best performing converters achieve moderately high peak efficiencies at high input voltage and medium power level. However, system dimensioning and cost are often...

47 CFR 73.6019 - Digital Class A TV station protection of low power TV, TV translator, digital low power TV and...

Science.gov (United States)

2010-10-01

... power TV, TV translator, digital low power TV and digital TV translator stations. 73.6019 Section 73... low power TV, TV translator, digital low power TV and digital TV translator stations. An application... A TV station will not be accepted if it fails to protect authorized low power TV, TV translator...

Information needs in nuclear power plants during low power operation modes

Energy Technology Data Exchange (ETDEWEB)

Tommila, Teemu; Fantoni, Paolo F.; Zander, Ralf M.

1998-02-01

During the past few years an increasing attention has been paid to the safety of shutdown and refuelling operations. It has turned out that the risks during shutdown may be comparable to the risks of power operation. The goal of this report is to identify information requirements related to low power operating modes of nuclear power plants. These include, for example, warm and cold shutdowns, refuelling and maintenance, as well as related state transitions such as start-up and shut-down. The focus of the report is on planned refuelling outages and the role of the control room in managing the outage activities. As a starting point, the basic terminology and characteristics of low power operation are discussed. The current situation at nuclear power plants and some recent developments in information technology are reviewed. End-users' requirements and enabling technologies are combined in order to identify the opportunities for new information technology tools in low power operation. The required features of process control systems and maintenance information systems are described. Common plant modelling techniques, open software architectures and functional structuring of the process control system are suggested to be the key issues in the long-term development of operator support systems. On a shorter time scale, new tools solving limited practical problems should be developed and evaluated. This would provide a basis for the features needed for low power operation, including for example, outage planning, on-line risk monitoring, management of outage tasks, adaptive alarm handling, computerised procedures and task-oriented human interfaces. (author)

A Low-Power and Low-Voltage Power Management Strategy for On-Chip Micro Solar Cells

Directory of Open Access Journals (Sweden)

Ismail Cevik

2015-01-01

Full Text Available Fundamental characteristics of on-chip micro solar cell (MSC structures were investigated in this study. Several MSC structures using different layers in three different CMOS processes were designed and fabricated. Effects of PN junction structure and process technology on solar cell performance were measured. Parameters for low-power and low-voltage implementation of power management strategy and boost converter based circuits utilizing fractional voltage maximum power point tracking (FVMPPT algorithm were determined. The FVMPPT algorithm works based on the fraction between the maximum power point operation voltage and the open circuit voltage of the solar cell structure. This ratio is typically between 0.72 and 0.78 for commercially available poly crystalline silicon solar cells that produce several watts of power under typical daylight illumination. Measurements showed that the fractional voltage ratio is much higher and fairly constant between 0.82 and 0.85 for on-chip mono crystalline silicon micro solar cell structures that produce micro watts of power. Mono crystalline silicon solar cell structures were observed to result in better power fill factor (PFF that is higher than 74% indicating a higher energy harvesting efficiency.

Ultra-low power high temperature and radiation hard complementary metal-oxide-semiconductor (CMOS) silicon-on-insulator (SOI) voltage reference.

Science.gov (United States)

Boufouss, El Hafed; Francis, Laurent A; Kilchytska, Valeriya; Gérard, Pierre; Simon, Pascal; Flandre, Denis

2013-12-13

This paper presents an ultra-low power CMOS voltage reference circuit which is robust under biomedical extreme conditions, such as high temperature and high total ionized dose (TID) radiation. To achieve such performances, the voltage reference is designed in a suitable 130 nm Silicon-on-Insulator (SOI) industrial technology and is optimized to work in the subthreshold regime of the transistors. The design simulations have been performed over the temperature range of -40-200 °C and for different process corners. Robustness to radiation was simulated using custom model parameters including TID effects, such as mobilities and threshold voltages degradation. The proposed circuit has been tested up to high total radiation dose, i.e., 1 Mrad (Si) performed at three different temperatures (room temperature, 100 °C and 200 °C). The maximum drift of the reference voltage V(REF) depends on the considered temperature and on radiation dose; however, it remains lower than 10% of the mean value of 1.5 V. The typical power dissipation at 2.5 V supply voltage is about 20 μW at room temperature and only 75 μW at a high temperature of 200 °C. To understand the effects caused by the combination of high total ionizing dose and temperature on such voltage reference, the threshold voltages of the used SOI MOSFETs were extracted under different conditions. The evolution of V(REF) and power consumption with temperature and radiation dose can then be explained in terms of the different balance between fixed oxide charge and interface states build-up. The total occupied area including pad-ring is less than 0.09 mm2.

Low power unattended defense reactor

International Nuclear Information System (INIS)

Kirchner, W.L.; Meier, K.L.

1984-01-01

A small, low power, passive, nuclear reactor electric power supply has been designed for unattended defense applications. Through innovative utilization of existing proven technologies and components, a highly reliable, ''walk-away safe'' design has been obtained. Operating at a thermal power level of 200 kWt, the reactor uses low enrichment uranium fuel in a graphite block core to generate heat that is transferred through heat pipes to a thermoelectric (TE) converter. Waste heat is removed from the TEs by circulation of ambient air. Because such a power supply offers the promise of minimal operation and maintenance (OandM) costs as well as no fuel logistics, it is particularly attractive for remote, unattended applications such as the North Warning System

Low power unattended defense reactor

International Nuclear Information System (INIS)

Kirchner, W.L.; Meier, K.L.

1984-01-01

A small, low power, passive, nuclear reactor electric power supply has been designed for unattended defense applications. Through innovative utilization of existing proven technologies and components, a highly reliable, walk-away safe design has been obtained. Operating at a thermal power level of 200 kWt, the reactor uses low enrichment uranium fuel in a graphite block core to generate heat that is transferred through heat pipes to a thermoelectric (TE) converter. Waste heat is removed from the TEs by circulation of ambient air. Because such a power supply offers the promise of minimal operation and maintenance (O and M) costs as well as no fuel logistics, it is particularly attractive for remote, unattended applications such as the North Warning System

Thermometric- and Acoustic-Based Beam Power Monitor for Ultra-Bright X-Rays

International Nuclear Information System (INIS)

2010-01-01

A design for an average beam power monitor for ultra-bright X-ray sources is proposed that makes simultaneous use of calorimetry and radiation acoustics. Radiation incident on a solid target will induce heating and ultrasonic vibrations, both of which may be measured to give a fairly precise value of the beam power. The monitor is intended for measuring ultra-bright Free-Electron Laser (FEL) X-ray beams, for which traditional monitoring technologies such as photo-diodes or scintillators are unsuitable. The monitor consists of a Boron Carbide (B 4 C) target designed to absorb most of the incident beam's energy. Resistance temperature detectors (RTD) and piezoelectric actuators are mounted on the outward faces of the target to measure the temperature changes and ultrasonic vibrations induced by the incident beam. The design was tested using an optical pulsed beam (780 nm, 120 and 360 Hz) from a Ti:sapphire oscillator at several energies between 0.8 and 2.6 mJ. The RTDs measured an increase in temperature of about 10 K over a period of several minutes. The piezoelectric sensors recorded ringing acoustic oscillations at 580 ± 40 kHz. Most importantly, the amplitude of the acoustic signals was observed to scale linearly with beam power up to 2 mJ of pulse energy. Above this pulse energy, the vibrational signals became nonlinear. Several causes for this nonlinearity are discussed, including amplifier saturation and piezoelectric saturation. Despite this nonlinearity, these measurements demonstrate the feasibility of such a beam power measurement device. The advantage of two distinct measurements (acoustic and thermometric) provides a useful method of calibration that is unavailable to current LCLS diagnostics tools.

Low-power wide-locking-range injection-locked frequency divider for OFDM UWB systems

Energy Technology Data Exchange (ETDEWEB)

Yin Jiangwei; Li Ning; Zheng Renliang; Li Wei; Ren Junyan, E-mail: lining@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

2009-05-01

This paper describes a divide-by-two injection-locked frequency divider (ILFD) for frequency synthesizers as used in multiband orthogonal frequency division multiplexing (OFDM) ultra-wideband (UWB) systems. By means of dual-injection technique and other conventional tuning techniques, such as DCCA and varactor tuning, the divider demonstrates a wide locking range while consuming much less power. The chip was fabricated in the Jazz 0.18 mum RF CMOS process. The measurement results show that the divider achieves a locking range of 4.85 GHz (6.23 to 11.08 GHz) at an input power of 8 dBm. The core circuit without the test buffer consumes only 3.7 mA from a 1.8 V power supply and has a die area of 0.38 x 0.28 mm{sup 2}. The wide locking range combined with low power consumption makes the ILFD suitable for its application in UWB systems.

Low-power wide-locking-range injection-locked frequency divider for OFDM UWB systems

International Nuclear Information System (INIS)

Yin Jiangwei; Li Ning; Zheng Renliang; Li Wei; Ren Junyan

2009-01-01

This paper describes a divide-by-two injection-locked frequency divider (ILFD) for frequency synthesizers as used in multiband orthogonal frequency division multiplexing (OFDM) ultra-wideband (UWB) systems. By means of dual-injection technique and other conventional tuning techniques, such as DCCA and varactor tuning, the divider demonstrates a wide locking range while consuming much less power. The chip was fabricated in the Jazz 0.18 μm RF CMOS process. The measurement results show that the divider achieves a locking range of 4.85 GHz (6.23 to 11.08 GHz) at an input power of 8 dBm. The core circuit without the test buffer consumes only 3.7 mA from a 1.8 V power supply and has a die area of 0.38 x 0.28 mm 2 . The wide locking range combined with low power consumption makes the ILFD suitable for its application in UWB systems.

Reconfigurable Ultra-Low Power Miniaturized EVA Radio, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — EVA radio is an important integral part of lunar missions and beyond. To minimize power consumption and mass of an EVA radio, innovative solutions are needed for the...

Low-power wind plants

International Nuclear Information System (INIS)

Kovalenko, V.I.; Shevchenko, Yu.V.; Shikhajlov, N.A.; Kokhanevich, V.P.; Tanan, G.L.

1993-01-01

Design peculiarities, as well as the prospects of development and introduction of the low-power (from 0.5 up to 4 kW) wind power plants (WPP) are considered. The variants of WPP with vertical and horizontal rotation axis are described. The data characterizing cost and structure of expenditures on WPP manufacture and operation are given

Optimizing efficiency on conventional transformer based low power AC/DC standby power supplies

DEFF Research Database (Denmark)

Nielsen, Nils

2004-01-01

This article describes the research results for simple and cheap methods to reduce the idle- and load-losses in very low power conventional transformer based power supplies intended for standby usage. In this case "very low power" means 50 Hz/230 V-AC to 5 V-DC@1 W. The efficiency is measured...... on two common power supply topologies designed for this power level. The two described topologies uses either a series (or linear) or a buck regulation approach. Common to the test power supplies is they either are using a standard cheap off-the-shelf transformer, or one, which are loss optimized by very...

Damping of Low Frequency Power System Oscillations with Wind Power Plants

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz

of wind power plants on power system low frequency oscillations and identify methods and limitations for potential contribution to the damping of such oscillations. Consequently, the first part of the studies focuses on how the increased penetration of wind power into power systems affects their natural...... oscillatory performance. To do so, at first a generic test grid displaying a complex inter-area oscillation pattern is introduced. After the evaluation of the test grid oscillatory profile for various wind power penetration scenarios, it is concluded that full-converter based wind power plant dynamics do......-synchronous power source. The main body of the work is devoted to the damping control design for wind power plants with focus on the impact of such control on the plant operation. It can be expected that the referred impact is directly proportional to the control effort, which for power processing devices should...

A 32 kb 9T near-threshold SRAM with enhanced read ability at ultra-low voltage operation

Science.gov (United States)

Kim, Tony Tae-Hyoung; Lee, Zhao Chuan; Do, Anh Tuan

2018-01-01

Ultra-low voltage SRAMs are highly sought-after in energy-limited systems such as battery-powered and self-harvested SoCs. However, ultra-low voltage operation diminishes SRAM read bitline (RBL) sensing margin significantly. This paper tackles this issue by presenting a novel 9T cell with data-independent RBL leakage in combination with an RBL boosting technique for enhancing the sensing margin. The proposed technique automatically tracks process, temperature and voltage (PVT) variations for robust sensing margin enhancement. A test chip fabricated in 65 nm CMOS technology shows that the proposed scheme significantly enlarges the sensing margin compared to the conventional bitline sensing scheme. It also achieves the minimum operating voltage of 0.18 V and the minimum energy consumption of 0.92 J/access at 0.4 V. He received 2016 International Low Power Design Contest Award from ISLPED, a best paper award at 2014 and 2011 ISOCC, 2008 AMD/CICC Student Scholarship Award, 2008 Departmental Research Fellowship from Univ. of Minnesota, 2008 DAC/ISSCC Student Design Contest Award, 2008, 2001, and 1999 Samsung Humantec Thesis Award and, 2005 ETRI Journal Paper of the Year Award. He is an author/co-author of +100 journal and conference papers and has 17 US and Korean patents registered. His current research interests include low power and high performance digital, mixed- mode, and memory circuit design, ultra-low voltage circuits and systems design, variation and aging tolerant circuits and systems, and circuit techniques for 3D ICs. He serves as an associate editor of IEEE Transactions on VLSI Systems. He is an IEEE senior member and the Chair of IEEE Solid-State Circuits Society Singapore Chapter. He has served numerous conferences as a committee member.

In-core neutron flux measurements at PARR using self powered neutron detector

International Nuclear Information System (INIS)

Hussain, A.; Ansari, S.A.

1989-10-01

This report describes experimental reactor physics measure ments at PARR using the in-core neutron detectors. Rhodium self powered neutron detectors (SPND) were used in the PARR core and several measurements were made aimed at detector calibration, response time determination and neutron flux measurements. The detectors were calibrated at low power using gold foils and full power by the thermal channel. Based on this calibration it was observed that the detector response remains almost linear throughout the power range. The self powered detectors were used for on-line determination of absolute neutron flux in the core as well as the spatial distribution of neutron flux or reactor power. The experimental, axial and horizontal flux mapping results at certain locations in the core are presented. The total response time of rhodium detector was experimentally determined to be about 5 minutes, which agree well with the theoretical results. Because of longer response time of SPND of the detectors it is not possible to use them in the reactor protection system. (author). 10 figs

Self-powered enzyme micropumps

Science.gov (United States)

Sengupta, Samudra; Patra, Debabrata; Ortiz-Rivera, Isamar; Agrawal, Arjun; Shklyaev, Sergey; Dey, Krishna K.; Córdova-Figueroa, Ubaldo; Mallouk, Thomas E.; Sen, Ayusman

2014-05-01

Non-mechanical nano- and microscale pumps that function without the aid of an external power source and provide precise control over the flow rate in response to specific signals are needed for the development of new autonomous nano- and microscale systems. Here we show that surface-immobilized enzymes that are independent of adenosine triphosphate function as self-powered micropumps in the presence of their respective substrates. In the four cases studied (catalase, lipase, urease and glucose oxidase), the flow is driven by a gradient in fluid density generated by the enzymatic reaction. The pumping velocity increases with increasing substrate concentration and reaction rate. These rechargeable pumps can be triggered by the presence of specific analytes, which enables the design of enzyme-based devices that act both as sensor and pump. Finally, we show proof-of-concept enzyme-powered devices that autonomously deliver small molecules and proteins in response to specific chemical stimuli, including the release of insulin in response to glucose.

Ultra-low power photoplethysmograhy SpO2 measuring techniques

Energy Technology Data Exchange (ETDEWEB)

Barriuso Medrano, C.; Calpe Maravilla, J.; Millan Navarro, C.

2016-07-01

Photoplethysmograph(y (PPG) is widely used to obtain vital signs such as the peripheral capillary oxygen saturation or the heart rate (HR) non-invasively in real time. These techniques require a great amount of power in order to obtain reliable data, and its use is limited to mains powered devices. For this reason it is of great importance to find methods and algorithms that reduce its current consumption. Three techniques to optimize current consumption when obtaining PPG signals are proposed in this study. Each of them takes advantage of the fact that to obtain these vital signs we only need the peaks of the PPG signal, which means that we may change the accuracy of the acquisition depending on the position within the pulse. The current consumption can be reduced by 55% in the sensor and 62% in the microcontroller. (Author)

Transient response of self-powered neutron detectors

International Nuclear Information System (INIS)

Boeck, H.; Gebureck, P.; Stegemann, D.

The behaviour of self-powered neutron detectors with Co, Er, Hf and Pt emitters was investigated during reactor square wave and pulse operation. The detector's response was compared with the current of an excore ionization chamber. Characteristical deviations from linearity were observed with all detectors at fast reactor periods. The exact cause of these deviations is not yet fully understood but several possibilities for the nonlinear behaviour of self-powered neutron detectors are outlined. (author)

Power Provision Based on Self-Sacrificing Craft

Science.gov (United States)

Hinchey, Michael G. (Inventor); Vassev, Emil I. (Inventor); Hinchey, Bridget (Inventor); Sterrit, Roy (Inventor)

2015-01-01

A biologically-inspired system and method is provided for self-adapting behavior of swarm-based exploration missions, whereby individual components, for example, spacecraft, in the system can sacrifice themselves for the greater good of the entire system. The self-sacrifice can involve donating resources or assets, such as power provisions, to a different component of an autonomous system. A receiving component of the system can benefit from receiving the donated resource or power provision.

Self-Biased 215MHz Magnetoelectric NEMS Resonator for Ultra-Sensitive DC Magnetic Field Detection

Science.gov (United States)

Nan, Tianxiang; Hui, Yu; Rinaldi, Matteo; Sun, Nian X.

2013-06-01

High sensitivity magnetoelectric sensors with their electromechanical resonance frequencies electromechanical systems (NEMS) resonator with an electromechanical resonance frequency of 215 MHz based on an AlN/(FeGaB/Al2O3) × 10 magnetoelectric heterostructure for detecting DC magnetic fields. This magnetoelectric NEMS resonator showed a high quality factor of 735, and strong magnetoelectric coupling with a large voltage tunable sensitivity. The admittance of the magnetoelectric NEMS resonator was very sensitive to DC magnetic fields at its electromechanical resonance, which led to a new detection mechanism for ultra-sensitive self-biased RF NEMS magnetoelectric sensor with a low limit of detection of DC magnetic fields of ~300 picoTelsa. The magnetic/piezoelectric heterostructure based RF NEMS magnetoelectric sensor is compact, power efficient and readily integrated with CMOS technology, which represents a new class of ultra-sensitive magnetometers for DC and low frequency AC magnetic fields.

High Efficiency Power Converter for Low Voltage High Power Applications

DEFF Research Database (Denmark)

Nymand, Morten

The topic of this thesis is the design of high efficiency power electronic dc-to-dc converters for high-power, low-input-voltage to high-output-voltage applications. These converters are increasingly required for emerging sustainable energy systems such as fuel cell, battery or photo voltaic based...

Design and fabrication of micro-hotplates made on a polyimide foil: electrothermal simulation and characterization to achieve power consumption in the low mW range

International Nuclear Information System (INIS)

Courbat, J; Canonica, M; Briand, D; De Rooij, N F; Teyssieux, D

2011-01-01

The design of ultra-low power micro-hotplates on a polyimide (PI) substrate supported by thermal simulations and characterization is presented. By establishing a method for the thermal simulation of very small scale heating elements, the goal of this study was to decrease the power consumption of PI micro-hotplates to a few milliwatts to make them suitable for very low power applications. To this end, the mean heat transfer coefficients in air of the devices were extracted by finite element analysis combined with very precise thermographic measurements. A simulation model was implemented for these hotplates to investigate both the influence of their downscaling and the bulk micromachining of the polyimide substrate to lower their power consumptions. Simulations were in very good agreement with the experimental results. The main parameters influencing significantly the power consumption at such dimensions were identified and guidelines were defined allowing the design of very small (15 × 15 µm) and ultra-low power heating elements (6 mW at 300 °C). These very low power heating structures enable the realization of flexible sensors, such as gas, flow or wind sensors, for applications in autonomous wireless sensors networks or RFID applications and make them compatible with large-scale production on foil such as roll-to-roll or printing processes.

Estimation and harvesting of human heat power for wearable electronic devices

International Nuclear Information System (INIS)

Dziurdzia, P; Brzozowski, I; Bratek, P; Gelmuda, W; Kos, A

2016-01-01

The paper deals with the issue of self-powered wearable electronic devices that are capable of harvesting free available energy dissipated by the user in the form of human heat. The free energy source is intended to be used as a secondary power source supporting primary battery in a sensor bracelet. The main scope of the article is a presentation of the concept for a measuring setup used to quantitative estimation of heat power sources in different locations over the human body area. The crucial role in the measurements of the human heat plays a thermoelectric module working in the open circuit mode. The results obtained during practical tests are confronted with the requirements of the dedicated thermoelectric generator. A prototype design of a human warmth energy harvester with an ultra-low power DC-DC converter based on the LTC3108 circuit is analysed

Self-tuning wireless power transmission scheme based on on-line scattering parameters measurement and two-side power matching.

Science.gov (United States)

Luo, Yanting; Yang, Yongmin; Chen, Zhongsheng

2014-04-10

Sub-resonances often happen in wireless power transmission (WPT) systems using coupled magnetic resonances (CMR) due to environmental changes, coil movements or component degradations, which is a serious challenge for high efficiency power transmission. Thus self-tuning is very significant to keep WPT systems following strongly magnetic resonant conditions in practice. Traditional coupled-mode ways is difficult to solve this problem. In this paper a two-port power wave model is presented, where power matching and the overall systemic power transmission efficiency are firstly defined by scattering (S) parameters. Then we propose a novel self-tuning scheme based on on-line S parameters measurements and two-side power matching. Experimental results testify the feasibility of the proposed method. These findings suggest that the proposed method is much potential to develop strongly self-adaptive WPT systems with CMR.

Ultra-Low Inductance Design for a GaN HEMT Based 3L-ANPC Inverter

DEFF Research Database (Denmark)

Gurpinar, Emre; Castellazzi, Alberto; Iannuzzo, Francesco

2016-01-01

contributors to voltage overshoots and increase of switching losses, are discussed. The ultra-low inductance power cell design based on a four layer PCB with the aim to maximise the switching performance of GaN HEMTs is explained. Gate driver design for GaN HEMT devices is presented. Common-mode behaviours......In this paper, an ultra-low inductance power cell design for a 3L-ANPC based on 650 V GaN HEMT devices is presented. The 3L-ANPC topology with GaN HEMT devices and the selected modulation scheme suitable for wide-bandgap (WBG) devices are presented. The commutation loops, which are the main...

Utilization of biogas released from palm oil mill effluent for power generation using self-preheated reactor

International Nuclear Information System (INIS)

Hosseini, Seyed Ehsan; Wahid, Mazlan Abdul

2015-01-01

Highlights: • A lab-scale reactor called self-preheating flameless combustion (SPFC) system is experimented. • Feasibility of power generation by POME biogas is modeled using SPFC system. • 4 MW power is available by POME biogas utilization in a typical palm oil mill with 300,000 tons production. • The rate of power generation increases when 2% hydrogen is added to POME biogas ingredients. - Abstract: In palm oil mills, for one ton crude palm oil (CPO) production, 70 m"3 biogas is released from palm oil mill effluent (POME) which can endanger the environment. Palm oil mills without appropriate strategies for biogas collection can participate in greenhouse gases (GHGs) generation actively. In this paper, a typical palm oil mill with annual capacity of 300,000 ton oil palm production and 3 MW electricity demand is considered as a pilot plant and feasibility of power generation by POME biogas is modeled by Aspen Plus considering flameless mode in combustion system. A new design of lab-scale flameless reactor called self-preheated flameless combustion (SPFC) system is presented and employed in power generation modeling. In SPFC system, the flameless chamber is employed as a heater to preheat an oxidizer over the self-ignition temperature of the fuel. A helical stainless steel pipe (called self-preheating pipe) is installed inside the chamber to conduct the oxidizer from exhaust zone to the combustion zone inside the chamber and preheat oxidizer. In the flameless mode, the diluted oxidizer is injected to the helical pipe from the exhaust zone and the preheated oxidizer at the burner is conducted to the flameless furnace through a distributor. In SPFC system external heater for preheating oxidizer is removed and the rate of power generation increases. The results show that 10.8 MW power could be generated in ultra-lean POME biogas SPFC. However, the rate of pollutant especially CO_2 and NO_x is high in this circumstances. In stoichiometric condition, 4 MW power

Low-Power, Chip-Scale, Carbon Dioxide Gas Sensors for Spacesuit Monitoring

Science.gov (United States)

Rani, Asha; Shi, Chen; Thomson, Brian; Debnath, Ratan; Wen, Boamei; Motayed, Abhishek; Chullen, Cinda

2018-01-01

N5 Sensors, Inc. through a Small Business Technology Transfer (STTR) contract award has been developing ultra-small, low-power carbon dioxide (CO2) gas sensors, suited for monitoring CO2 levels inside NASA spacesuits. Due to the unique environmental conditions within the spacesuits, such as high humidity, large temperature swings, and operating pressure swings, measurement of key gases relevant to astronaut's safety and health such as(CO2), is quite challenging. Conventional non-dispersive infrared absorption based CO2 sensors present challenges inside the spacesuits due to size, weight, and power constraints, along with the ability to sense CO2 in a high humidity environment. Unique chip-scale, nanoengineered chemiresistive gas-sensing architecture has been developed for this application, which can be operated in a typical space-suite environmental conditions. Unique design combining the selective adsorption properties of the nanophotocatalytic clusters of metal-oxides and metals, provides selective detection of CO2 in high relative humidity conditions. All electronic design provides a compact and low-power solution, which can be implemented for multipoint detection of CO2 inside the spacesuits. This paper will describe the sensor architecture, development of new photocatalytic material for better sensor response, and advanced structure for better sensitivity and shorter response times.

Stable formation of ultrahigh power-density 248 nm channels in Xe cluster targets

Energy Technology Data Exchange (ETDEWEB)

Borisov, Alex B.; Racz, Ervin; Khan, Shahab F.; Poopalasingam, Sankar; McCorkindale, John C.; Boguta, John; Longworth, James W.; Rhodes, Charles K. [Laboratory for X-ray Microimaging and Bioinformatics, Department of Physics, University of Illinois at Chicago, Chicago, IL 60607-7059 (United States); KFKI Research Institute for Particle and Nuclear Physics, EURATOM Association, P.O. Box 49, 1525 Budapest (Hungary)

2012-07-11

The optimization of relativistic and ponderomotive self-channeling of ultra-powerful 248 nm laser pulses launched in underdense plasmas with an appropriate longitudinal gradient in the electron density profile located at the initial stage of the self-channeling leads to (1) stable channel formation and (2) highly efficient power compression producing power densities in the 10{sup 19}-10{sup 20} W/cm{sup 3} range. The comparison of theoretical studies with experimental results involving the correlation of (a) Thomson images of the electron density with (b) x-ray images of the channel morphology demonstrates that more than 90% of the incident 248 nm power can be trapped in stable channels and that this stable propagation can be extended to power levels significantly exceeding the critical power of the self-channeling process.

Low power reactor for remote applications

International Nuclear Information System (INIS)

Meier, K.L.; Palmer, R.G.; Kirchner, W.L.

1985-01-01

A compact, low power reactor is being designed to provide electric power for remote, unattended applications. Because of the high fuel and maintenance costs for conventional power sources such as diesel generators, a reactor power supply appears especially attractive for remote and inaccessible locations. Operating at a thermal power level of 135 kWt, the power supply achieves a gross electrical output of 25 kWe from an organic Rankine cycle (ORC) engine. By intentional selection of design features stressing inherent safety, operation in an unattended mode is possible with minimal risk to the environment. Reliability is achieved through the use of components representing existing, proven technology. Low enrichment uranium particle fuel, in graphite core blocks, cooled by heat pipes coupled to an ORC converter insures long-term, virtually maintenance free, operation of this reactor for remote applications. 10 refs., 7 figs., 3 tabs

Recent advances in flexible low power cholesteric LCDs

Science.gov (United States)

Khan, Asad; Shiyanovskaya, Irina; Montbach, Erica; Schneider, Tod; Nicholson, Forrest; Miller, Nick; Marhefka, Duane; Ernst, Todd; Doane, J. W.

2006-05-01

Bistable reflective cholesteric displays are a liquid crystal display technology developed to fill a market need for very low power displays. Their unique look, high reflectivity, bistability, and simple structure make them an ideal flat panel display choice for handheld or other portable devices where small lightweight batteries with long lifetimes are important. Applications ranging from low resolution large signs to ultra high resolution electronic books can utilize cholesteric displays to not only benefit from the numerous features, but also create enabling features that other flat panel display technologies cannot. Flexible displays are the focus of attention of numerous research groups and corporations worldwide. Cholesteric displays have been demonstrated to be highly amenable to flexible substrates. This paper will review recent advances in flexible cholesteric displays including both phase separation and emulsification approaches to encapsulation. Both approaches provide unique benefits to various aspects of manufacturability, processes, flexibility, and conformability.

An Intelligent Sensor for the Ultra-High-Frequency Partial Discharge Online Monitoring of Power Transformers

Directory of Open Access Journals (Sweden)

Jian Li

2016-05-01

Full Text Available Ultra-high-frequency (UHF partial discharge (PD online monitoring is an effective way to inspect potential faults and insulation defects in power transformers. The construction of UHF PD online monitoring system is a challenge because of the high-frequency and wide-frequency band of the UHF PD signal. This paper presents a novel, intelligent sensor for UHF PD online monitoring based on a new method, namely a level scanning method. The intelligent sensor can directly acquire the statistical characteristic quantities and is characterized by low cost, few data to output and transmit, Ethernet functionality, and small size for easy installation. The prototype of an intelligent sensor was made. Actual UHF PD experiments with three typical artificial defect models of power transformers were carried out in a laboratory, and the waveform recording method and intelligent sensor proposed were simultaneously used for UHF PD measurement for comparison. The results show that the proposed intelligent sensor is qualified for the UHF PD online monitoring of power transformers. Additionally, three methods to improve the performance of intelligent sensors were proposed according to the principle of the level scanning method.

Ultra-Portable Solar-Powered 3D Printers for Onsite Manufacturing of Medical Resources.

Science.gov (United States)

Wong, Julielynn Y

2015-09-01

The first space-based fused deposition modeling (FDM) 3D printer is powered by solar photovoltaics. This study seeks to demonstrate the feasibility of using solar energy to power a FDM 3D printer to manufacture medical resources at the Mars Desert Research Station and to design an ultra-portable solar-powered 3D printer for off-grid environments. Six solar panels in a 3×2 configuration, a voltage regulator/capacitor improvised from a power adapter, and two 12V batteries in series were connected to power a FDM 3D printer. Three designs were printed onsite and evaluated by experts post analogue mission. A solar-powered 3D printer composed of off-the-shelf components was designed to be transported in airline carry-on luggage. During the analogue mission, the solar-powered printer could only be operated for solar-powered 3D printer was designed that could print an estimated 16 dental tools or 8 mallet finger splints or 7 scalpel handles on one fully charged 12V 150Wh battery with a 110V AC converter. It is feasible to use solar energy to power a 3D printer to manufacture functional and personalized medical resources at a Mars analogue research station. Based on these findings, a solar-powered suitcase 3D printing system containing solar panels, 12V battery with charge controller and AC inverter, and back-up solar charge controller and inverter was designed for transport to and use in off-grid communities.

A study on water level control of PWR steam generator at low power and the self-tuning of its fuzzy controller

International Nuclear Information System (INIS)

Na, N.; Kwon, K.; Ham, C.; Bien, Z.

1994-01-01

The water level control system of a steam generator in a pressurized water reactor and its control problems during the operation at low power is analysed. In particular, a strategy for a water level control system, which is based on the use of a fuzzy logic controller, is proposed. The control strategy includes dynamic tuning for the large transient. The fuzzy variable of the flow rate during the power operation is obtained from the bypass valve opening and not from the incorrect measured signal at the low flow rate. The practical self-tuning algorithm is based on the optimal control performance

Thermal power blocks with ultra-super-critical steam parameters

Directory of Open Access Journals (Sweden)

Aličić Merim M.

2016-01-01

Full Text Available New generation of thermal power plants are required to have increased utilization rates, in addition to reduced emissions of pollutants, in order to reach optimal solutions, from both technical and economic point of view. One way to achieve greater utilization efficiency is operation of the plant at super critical (SC or ultra super critical steam parameters (USC. However, achieving high parameters depends on use of new materials, which have better properties at high temperatures and pressures, use of new welding technologies and by solving the problem of corrosion. The paper gives an overview of some of the plants with these parameters.

Ultra-low power high precision magnetotelluric receiver array based customized computer and wireless sensor network

Science.gov (United States)

Chen, R.; Xi, X.; Zhao, X.; He, L.; Yao, H.; Shen, R.

2016-12-01

Dense 3D magnetotelluric (MT) data acquisition owns the benefit of suppressing the static shift and topography effect, can achieve high precision and high resolution inversion for underground structure. This method may play an important role in mineral exploration, geothermal resources exploration, and hydrocarbon exploration. It's necessary to reduce the power consumption greatly of a MT signal receiver for large-scale 3D MT data acquisition while using sensor network to monitor data quality of deployed MT receivers. We adopted a series of technologies to realized above goal. At first, we designed an low-power embedded computer which can couple with other parts of MT receiver tightly and support wireless sensor network. The power consumption of our embedded computer is less than 1 watt. Then we designed 4-channel data acquisition subsystem which supports 24-bit analog-digital conversion, GPS synchronization, and real-time digital signal processing. Furthermore, we developed the power supply and power management subsystem for MT receiver. At last, a series of software, which support data acquisition, calibration, wireless sensor network, and testing, were developed. The software which runs on personal computer can monitor and control over 100 MT receivers on the field for data acquisition and quality control. The total power consumption of the receiver is about 2 watts at full operation. The standby power consumption is less than 0.1 watt. Our testing showed that the MT receiver can acquire good quality data at ground with electrical dipole length as 3 m. Over 100 MT receivers were made and used for large-scale geothermal exploration in China with great success.

Ultra-short pulse delivery at high average power with low-loss hollow core fibers coupled to TRUMPF's TruMicro laser platforms for industrial applications

Science.gov (United States)

Baumbach, S.; Pricking, S.; Overbuschmann, J.; Nutsch, S.; Kleinbauer, J.; Gebs, R.; Tan, C.; Scelle, R.; Kahmann, M.; Budnicki, A.; Sutter, D. H.; Killi, A.

2017-02-01

Multi-megawatt ultrafast laser systems at micrometer wavelength are commonly used for material processing applications, including ablation, cutting and drilling of various materials or cleaving of display glass with excellent quality. There is a need for flexible and efficient beam guidance, avoiding free space propagation of light between the laser head and the processing unit. Solid core step index fibers are only feasible for delivering laser pulses with peak powers in the kW-regime due to the optical damage threshold in bulk silica. In contrast, hollow core fibers are capable of guiding ultra-short laser pulses with orders of magnitude higher peak powers. This is possible since a micro-structured cladding confines the light within the hollow core and therefore minimizes the spatial overlap between silica and the electro-magnetic field. We report on recent results of single-mode ultra-short pulse delivery over several meters in a lowloss hollow core fiber packaged with industrial connectors. TRUMPF's ultrafast TruMicro laser platforms equipped with advanced temperature control and precisely engineered opto-mechanical components provide excellent position and pointing stability. They are thus perfectly suited for passive coupling of ultra-short laser pulses into hollow core fibers. Neither active beam launching components nor beam trackers are necessary for a reliable beam delivery in a space and cost saving packaging. Long term tests with weeks of stable operation, excellent beam quality and an overall transmission efficiency of above 85 percent even at high average power confirm the reliability for industrial applications.

Self-powered detectors with thulium emitter

International Nuclear Information System (INIS)

Haller, P.; Klar, E.

1978-01-01

In addition to fission chambers, prompt-indicating self-powered (SPN) detectors are used for measuring the neutron flux density in the core of power reactors. Although current SPN detectors with a cobalt emitter give satisfactora results, detectors with other emitter materials have been analyzed and tested. The author describes the properties and decay pattern of the nuclide thulium and presents the results of measurements made while testing thulium detectors. (orig.) [de

Self-powered neutron detector

International Nuclear Information System (INIS)

Goldstein, N.P.; Todt, W.H.

1974-01-01

The invention relates a self-powered neutron detector comprising an emitting body, an insulating material surrounding said body, and a conducting outer cover, a power conductor connected to the emitting body and passing through the insulating material permitting to insert an ammeter between said emitting body and said cover. The invention is characterized in that said emitting body is surrounded by a thin conducting layer of small cross section for neutrons made of high density material said material being capable of absorbing the beta-radiations due to the degradation of the emitting body activating product, while transmitting the fast electrons of high average energy emitted by said emitting body. This can be applied to safety control devices required to provide a quick answer [fr

A novel self-powered wireless temperature sensor based on thermoelectric generators

International Nuclear Information System (INIS)

Shi, Yongming; Wang, Yao; Deng, Yuan; Gao, Hongli; Lin, Zhen; Zhu, Wei; Ye, Huihong

2014-01-01

Highlights: • A self-powered temperature sensor, based on thermoelectric generator, is presented. • This novel sensor can operate without any batteries or other power sources. • This sensor combines signal sensing and power supplying together. • The measurement error is 0.5 K during the sensor operating period. • This sensor can detect temperature fluctuation situations such as fire disaster. - Abstract: A novel self-powered wireless temperature sensor has been designed and presented for solving the power supply problem of temperature sensors. This sensor can autonomously measure temperature under positive temperature fluctuation situations. The self-powered characteristic, realized by using four thermoelectric generators, enables the sensor to operate without any batteries or other power sources. In order to obtain these features, attentions are not only focused on the method to combine signal sensing and power generating together, but also on the method to improve measurement accuracy. Experimental results confirm that this novel sensor has excellent measurement accuracy. The measured performance is consistent with the calculated characteristics. For typical application, this self-powered temperature sensor can detect fire before it develops to flashover state. And the maximum detection distance grows with the growth of burning rate. All the results indicate this innovative sensor is a promising self-powered device which can be used to measure temperature value in positive temperature fluctuation situations

IEEE-802.15.4-based low-power body sensor node with RF energy harvester.

Science.gov (United States)

Tran, Thang Viet; Chung, Wan-Young

2014-01-01

This paper proposes the design and implementation of a low-voltage and low-power body sensor node based on the IEEE 802.15.4 standard to collect electrocardiography (ECG) and photoplethysmography (PPG) signals. To achieve compact size, low supply voltage, and low power consumption, the proposed platform is integrated into a ZigBee mote, which contains a DC-DC booster, a PPG sensor interface module, and an ECG front-end circuit that has ultra-low current consumption. The input voltage of the proposed node is very low and has a wide range, from 0.65 V to 3.3 V. An RF energy harvester is also designed to charge the battery during the working mode or standby mode of the node. The power consumption of the proposed node reaches 14 mW in working mode to prolong the battery lifetime. The software is supported by the nesC language under the TinyOS environment, which enables the proposed node to be easily configured to function as an individual health monitoring node or a node in a wireless body sensor network (BSN). The proposed node is used to set up a wireless BSN that can simultaneously collect ECG and PPG signals and monitor the results on the personal computer.

Exploration of Sub-VT and Near-VT 2T Gain-Cell Memories for Ultra-Low Power Applications under Technology Scaling

Directory of Open Access Journals (Sweden)

Alexander Fish

2013-04-01

Full Text Available Ultra-low power applications often require several kb of embedded memory and are typically operated at the lowest possible operating voltage (VDD to minimize both dynamic and static power consumption. Embedded memories can easily dominate the overall silicon area of these systems, and their leakage currents often dominate the total power consumption. Gain-cell based embedded DRAM arrays provide a high-density, low-leakage alternative to SRAM for such systems; however, they are typically designed for operation at nominal or only slightly scaled supply voltages. This paper presents a gain-cell array which, for the first time, targets aggressively scaled supply voltages, down into the subthreshold (sub-VT domain. Minimum VDD design of gain-cell arrays is evaluated in light of technology scaling, considering both a mature 0.18 μm CMOS node, as well as a scaled 40 nm node. We first analyze the trade-offs that characterize the bitcell design in both nodes, arriving at a best-practice design methodology for both mature and scaled technologies. Following this analysis, we propose full gain-cell arrays for each of the nodes, operated at a minimum VDD. We find that an 0.18 μm gain-cell array can be robustly operated at a sub-VT supply voltage of 400mV, providing read/write availability over 99% of the time, despite refresh cycles. This is demonstrated on a 2 kb array, operated at 1 MHz, exhibiting full functionality under parametric variations. As opposed to sub-VT operation at the mature node, we find that the scaled 40 nm node requires a near-threshold 600mV supply to achieve at least 97% read/write availability due to higher leakage currents that limit the bitcell’s retention time. Monte Carlo simulations show that a 600mV 2 kb 40 nm gain-cell array is fully functional at frequencies higher than 50 MHz.

SELF-POWERED WIRELESS SENSOR NODE POWER MODELING BASED ON IEEE 802.11 COMMUNICATION PROTOCOL

Energy Technology Data Exchange (ETDEWEB)

Vivek Agarwal; Raymond A. DeCarlo; Lefteri H. Tsoukalas

2016-04-01

Design and technical advancements in sensing, processing, and wireless communication capabilities of small, portable devices known as wireless sensor nodes (WSNs) have drawn extensive research attention and are vastly applied in science and engineering applications. The WSNs are typically powered by a chemical battery source that has a load dependent finite lifetime. Most applications, including the nuclear industry applications, require WSNs to operate for an extended period of time beginning with their deployment. To ensure longevity, it is important to develop self-powered WSNs. The benefit of self-powered WSNs goes far beyond the cost savings of removing the need for cable installation and maintenance. Self-powered WSNs will potentially offer significant expansion in remote monitoring of nuclear facilities, and provide important data on plant equipment and component status during normal operation, as well as in case of abnormal operation, station blackouts or post-accident evaluation. Advancements in power harvesting technologies enable electric energy generation from many sources, including kinetic, thermal, and radiated energy. For the ongoing research at Idaho National Laboratory, a solid-state thermoelectric-based technology, the thermoelectric generator (TEG), is used to convert thermal energy to power a WSN. The design and development of TEGs to power WSNs that would remain active for a long period of time requires comprehensive understanding of WSN operational. This motivates the research in modeling the lifetime, i.e., power consumption, of a WSN by taking into consideration various node and network level activities. A WSN must perform three essential tasks: sense events, perform quick local information processing of sensed events, and wirelessly exchange locally processed data with the base station or with other WSNs in the network. Each task has a power cost per unit tine and an additional cost when switching between tasks. There are number of other

The first in Poland demonstrative ORC power plant of low power output

Energy Technology Data Exchange (ETDEWEB)

Nowak, Wladyslaw; Borsukiewicz-Gozdur, Aleksandra; Stachel, Aleksander A. [West Pomeranian Univ. of Technology, Szczecin (Poland); Klonowicz, Wojciech; Hanausek, Pawel [Turboservice Sp. z o.o., Lodz (Poland); Klonowicz, Piotr; Magiera, Radomir [Lodz Univ. of Technology (Poland)

2010-07-01

A description of the power plant working according to the organic Clausius-Rankine cycle (ORC) and developed at the Department of Heat Engineering (KTC), West Pomeranian University of Technology in Szczecin, is presented. The ORC power plant is powered by the low temperature heat of hot water with the temperature of up to 100 C. The hot water heat is here converted into mechanical energy that is generated by a turbine and used to drive a centrifugal air compressor. The ORC turbine is supplied with dry, saturated vapour of the R227ea working fluid of low boiling point. The working fluid vapour is generated in a combined preheater-evaporator heat exchanger. The results of calculations and experimental measurements are presented and supplemented with conclusions derived from the ORC power plant operation. Perspective modernization of the ORC power plant scheme is also outlined. (orig.)

Shutdown and low-power operation at commercial nuclear power plants in the United States

International Nuclear Information System (INIS)

1993-09-01

The report contains the results of the NRC Staff's evaluation of shutdown and low-power operations at US commercial nuclear power plants. The report describes studies conducted by the staff in the following areas: Operating experience related to shutdown and low-power operations, probabilistic risk assessment of shutdown and low-power conditions and utility programs for planning and conducting activities during periods the plant is shut down. The report also documents evaluations of a number of technical issues regarding shutdown and low-power operations performed by the staff, including the principal findings and conclusions. Potential new regulatory requirements are discussed, as well as potential changes in NRC programs. A draft report was issued for comment in February 1992. This report is the final version and includes the responses to the comments along with the staff regulatory analysis of potential new requirements

A Wireless Self-Powered Urinary Incontinence Sensor System

Science.gov (United States)

Tanaka, Ami; Utsunomiya, Fumiyasu; Douseki, Takakuni

A self-powered urinary incontinence sensor system consisting of a urine-activated coin battery and a wireless transmitter has been developed as an application for wireless biosensor networks. The urine-activated battery makes possible both the sensing of urine leakage and self-powered operation. An intermittent power-supply circuit that uses an electric double-layer capacitor (EDLC) with a small internal resistance suppresses the supply voltage drop due to the large internal resistance of the battery. This circuit and a 1-V surface acoustic wave (SAW) oscillator reduce the power dissipation of a wireless transmitter. The SAW oscillator quickly responds to the on-off control of the power supply, which is suitable for intermittent operation. To verify the effectiveness of the circuit scheme, the authors fabricated a prototype sensor system. When the volume of urine is 0.2 ml, the battery outputs a voltage of over 1.3 V; and the sensor system can transmit signals over a distance of 5 m.

Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to ‘Power Poses’

Directory of Open Access Journals (Sweden)

Agnieszka Golec de Zavala

2017-05-01

Full Text Available Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of ‘power poses,’ which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010. The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to ‘high power’ and ‘low power’ poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body (n = 19, two standing yoga poses with covered front of the body (n = 22, two expansive, high power poses (n = 21, or two constrictive, low power poses (n = 20 for 1-min each. The results showed that yoga poses in comparison to ‘power poses’ increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses’ association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min.

Hacking and penetration testing with low power devices

CERN Document Server

Polstra, Philip

2014-01-01

Hacking and Penetration Testing with Low Power Devices shows you how to perform penetration tests using small, low-powered devices that are easily hidden and may be battery-powered. It shows how to use an army of devices, costing less than you might spend on a laptop, from distances of a mile or more. Hacking and Penetration Testing with Low Power Devices shows how to use devices running a version of The Deck, a full-featured penetration testing and forensics Linux distribution, and can run for days or weeks on batteries due to their low power consumption. Author Philip Polstra shows how to

Authenticity and Relationship Satisfaction: Two Distinct Ways of Directing Power to Self-Esteem

Science.gov (United States)

Wang, Yi Nan

2015-01-01

Possessing power contributes to high self-esteem, but how power enhances self-esteem is still unknown. As power is associated with both self-oriented goals and social-responsibility goals, we proposed that power predicts self-esteem through two positive personal and interpersonal results: authenticity and relationship satisfaction. Three studies were carried out with a total of 505 Chinese participants, including college students and adults, who completed surveys that assessed personal power, self-esteem, authenticity, relationship satisfaction, communal orientation, and social desirability. Hierarchical multiple regression analyses demonstrated that power, authenticity, and relationship satisfaction each uniquely contributed to self-esteem. More importantly, multiple mediation analysis showed that authenticity and relationship satisfaction both mediated the effects of power on self-esteem, even when controlling for participants’ communal orientation and social desirability. Our findings demonstrate that authenticity and relationship satisfaction represent two key mechanisms by which power is associated with self-esteem. PMID:26720814

Authenticity and Relationship Satisfaction: Two Distinct Ways of Directing Power to Self-Esteem.

Science.gov (United States)

Wang, Yi Nan

2015-01-01

Possessing power contributes to high self-esteem, but how power enhances self-esteem is still unknown. As power is associated with both self-oriented goals and social-responsibility goals, we proposed that power predicts self-esteem through two positive personal and interpersonal results: authenticity and relationship satisfaction. Three studies were carried out with a total of 505 Chinese participants, including college students and adults, who completed surveys that assessed personal power, self-esteem, authenticity, relationship satisfaction, communal orientation, and social desirability. Hierarchical multiple regression analyses demonstrated that power, authenticity, and relationship satisfaction each uniquely contributed to self-esteem. More importantly, multiple mediation analysis showed that authenticity and relationship satisfaction both mediated the effects of power on self-esteem, even when controlling for participants' communal orientation and social desirability. Our findings demonstrate that authenticity and relationship satisfaction represent two key mechanisms by which power is associated with self-esteem.

Low Power Near Field Communication Methods for RFID Applications of SIM Cards.

Science.gov (United States)

Chen, Yicheng; Zheng, Zhaoxia; Gong, Mingyang; Yu, Fengqi

2017-04-14

Power consumption and communication distance have become crucial challenges for SIM card RFID (radio frequency identification) applications. The combination of long distance 2.45 GHz radio frequency (RF) technology and low power 2 kHz near distance communication is a workable scheme. In this paper, an ultra-low frequency 2 kHz near field communication (NFC) method suitable for SIM cards is proposed and verified in silicon. The low frequency transmission model based on electromagnetic induction is discussed. Different transmission modes are introduced and compared, which show that the baseband transmit mode has a better performance. The low-pass filter circuit and programmable gain amplifiers are applied for noise reduction and signal amplitude amplification. Digital-to-analog converters and comparators are used to judge the card approach and departure. A novel differential Manchester decoder is proposed to deal with the internal clock drift in range-controlled communication applications. The chip has been fully implemented in 0.18 µm complementary metal-oxide-semiconductor (CMOS) technology, with a 330 µA work current and a 45 µA idle current. The low frequency chip can be integrated into a radio frequency SIM card for near field RFID applications.

An ultra low-power and traffic-adaptive medium access control protocol for wireless body area network.

Science.gov (United States)

Ullah, Sana; Kwak, Kyung Sup

2012-06-01

Wireless Body Area Network (WBAN) consists of low-power, miniaturized, and autonomous wireless sensor nodes that enable physicians to remotely monitor vital signs of patients and provide real-time feedback with medical diagnosis and consultations. It is the most reliable and cheaper way to take care of patients suffering from chronic diseases such as asthma, diabetes and cardiovascular diseases. Some of the most important attributes of WBAN is low-power consumption and delay. This can be achieved by introducing flexible duty cycling techniques on the energy constraint sensor nodes. Stated otherwise, low duty cycle nodes should not receive frequent synchronization and control packets if they have no data to send/receive. In this paper, we introduce a Traffic-adaptive MAC protocol (TaMAC) by taking into account the traffic information of the sensor nodes. The protocol dynamically adjusts the duty cycle of the sensor nodes according to their traffic-patterns, thus solving the idle listening and overhearing problems. The traffic-patterns of all sensor nodes are organized and maintained by the coordinator. The TaMAC protocol is supported by a wakeup radio that is used to accommodate emergency and on-demand events in a reliable manner. The wakeup radio uses a separate control channel along with the data channel and therefore it has considerably low power consumption requirements. Analytical expressions are derived to analyze and compare the performance of the TaMAC protocol with the well-known beacon-enabled IEEE 802.15.4 MAC, WiseMAC, and SMAC protocols. The analytical derivations are further validated by simulation results. It is shown that the TaMAC protocol outperforms all other protocols in terms of power consumption and delay.

Social power and recognition of emotional prosody: High power is associated with lower recognition accuracy than low power.

Science.gov (United States)

Uskul, Ayse K; Paulmann, Silke; Weick, Mario

2016-02-01

Listeners have to pay close attention to a speaker's tone of voice (prosody) during daily conversations. This is particularly important when trying to infer the emotional state of the speaker. Although a growing body of research has explored how emotions are processed from speech in general, little is known about how psychosocial factors such as social power can shape the perception of vocal emotional attributes. Thus, the present studies explored how social power affects emotional prosody recognition. In a correlational study (Study 1) and an experimental study (Study 2), we show that high power is associated with lower accuracy in emotional prosody recognition than low power. These results, for the first time, suggest that individuals experiencing high or low power perceive emotional tone of voice differently. (c) 2016 APA, all rights reserved).

Self-assembled ultra small ZnO nanocrystals for dye-sensitized solar cell application

Energy Technology Data Exchange (ETDEWEB)

Patra, Astam K.; Dutta, Arghya; Bhaumik, Asim, E-mail: msab@iacs.res.in

2014-07-01

We demonstrate a facile chemical approach to produce self-assembled ultra-small mesoporous zinc oxide nanocrystals using sodium salicylate (SS) as a template under hydrothermal conditions. These ZnO nanomaterials have been successfully fabricated as a photoanode for the dye-sensitized solar cell (DSSC) in the presence of N719 dye and iodine–triiodide electrolyte. The structural features, crystallinity, purity, mesophase and morphology of the nanostructure ZnO are investigated by several characterization tools. N{sub 2} sorption analysis revealed high surface areas (203 m{sup 2} g{sup −1}) and narrow pore size distributions (5.1–5.4 nm) for different samples. The mesoporous structure and strong photoluminescence facilitates the high dye loading at the mesoscopic void spaces and light harvesting in DSSC. By utilizing this ultra-small ZnO photoelectrode with film thickness of about 7 μm in the DSSC with an open-circuit voltage (V{sub OC}) of 0.74 V, short-circuit current density (J{sub SC}) of 3.83 mA cm{sup −2} and an overall power conversion efficiency of 1.12% has been achieved. - Graphical abstract: Ultra-small ZnO nanocrystals have been synthesized with sodium salicylate as a template and using it as a photoanode in a dye-sensitized solar cell 1.12% power conversion efficiency has been observed. - Highlights: • Synthesis of self-assembled ultra-small mesoporous ZnO nanocrystals by using sodium salicylate as a template. • Mesoporous ZnO materials have high BET surface areas and void space. • ZnO nanoparticles serve as a photoanode for the dye-sensitized solar cell (DSSC). • Using ZnO nanocrystals as photoelectrode power conversion efficiency of 1.12% has been achieved.

Novel design of a self powered and self sensing magneto-rheological damper

International Nuclear Information System (INIS)

Ferdaus, Mohammad Meftahul; Rashid, M M; Bhuiyan, M M I; Muthalif, Asan Gani Bin Abdul; Hasan, M R

2013-01-01

Magneto-rheological (MR) dampers are semi-active control devices and use MR fluids. Magneto-rheological dampers have successful applications in mechatronics engineering, civil engineering and numerous areas of engineering. At present, traditional MR damper systems, require a isolated power supply and dynamic sensor. This paper presents the achievability and accuracy of a self- powered and self-sensing magneto-rheological damper using harvested energy from the vibration and shock environment in which it is deployed and another important part of this paper is the increased yield stress of the Magneto rheological Fluids. Magneto rheological fluids using replacement of glass beads for Magnetic Particles to surge yield stress is implemented here. Clearly this shows better result on yield stress, viscosity, and settling rate. Also permanent magnet generator (PMG) is designed and attached to a MR damper. For evaluating the self-powered MR damper's vibration mitigating capacity, an Engine Mount System using the MR damper is simulated. The ideal stiffness of the PMG for the Engine Mount System (EMS) is calculated by numerical study. The vibration mitigating performance of the EMS employing the self-powered and self sensing MR damper is theoretically calculated and evaluated in the frequency domain

Novel design of a self powered and self sensing magneto-rheological damper

Science.gov (United States)

Meftahul Ferdaus, Mohammad; Rashid, M. M.; Bhuiyan, M. M. I.; Muthalif, Asan Gani Bin Abdul; Hasan, M. R.

2013-12-01

Magneto-rheological (MR) dampers are semi-active control devices and use MR fluids. Magneto-rheological dampers have successful applications in mechatronics engineering, civil engineering and numerous areas of engineering. At present, traditional MR damper systems, require a isolated power supply and dynamic sensor. This paper presents the achievability and accuracy of a self- powered and self-sensing magneto-rheological damper using harvested energy from the vibration and shock environment in which it is deployed and another important part of this paper is the increased yield stress of the Magneto rheological Fluids. Magneto rheological fluids using replacement of glass beads for Magnetic Particles to surge yield stress is implemented here. Clearly this shows better result on yield stress, viscosity, and settling rate. Also permanent magnet generator (PMG) is designed and attached to a MR damper. For evaluating the self-powered MR damper's vibration mitigating capacity, an Engine Mount System using the MR damper is simulated. The ideal stiffness of the PMG for the Engine Mount System (EMS) is calculated by numerical study. The vibration mitigating performance of the EMS employing the self-powered & self sensing MR damper is theoretically calculated and evaluated in the frequency domain.

An integrated low-voltage rated HTS DC power system with multifunctions to suit smart grids

Energy Technology Data Exchange (ETDEWEB)

Jin, Jian Xun, E-mail: jxjin@uestc.edu.cn [Center of Applied Superconductivity, School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China); Center of Applied Superconductivity and Electrical Engineering, School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu 611731 (China); Chen, Xiao Yuan [School of Engineering, Sichuan Normal University, Chengdu 610101 (China); Qu, Ronghai; Fang, Hai Yang [School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Xin, Ying [Center of Applied Superconductivity, School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China)

2015-03-15

Highlights: • A novel LVDC HTS power transmission network is presented. • An integrated power system is achieved by using HTS DC cable and SMES. • DC superconducting cable is verified to achieve self-acting fault current limitation. • SMES is verified to achieve fast-response buffering effect under a power fluctuation. • SMES is verified to achieve favorable load voltage protection effect under a fault. - Abstract: A low-voltage rated DC power transmission network integrated with superconducting cables (SCs) and superconducting magnetic energy storage (SMES) devices has been studied with analytic results presented. In addition to the properties of loss-less and high current transportation capacity, the effectively integrated system is formed with a self-acting fault current limitation feature of the SC and a buffering effect of the SMES to power fluctuations. The results obtained show that the integrated system can achieve high-quality power transmission under common power fluctuation conditions with an advanced self-protection feature under short circuit conditions, which is identified to suit especially the smart grid applications.

Ultra Low Energy Binary Decision Diagram Circuits Using Few Electron Transistors

Science.gov (United States)

Saripalli, Vinay; Narayanan, Vijay; Datta, Suman

Novel medical applications involving embedded sensors, require ultra low energy dissipation with low-to-moderate performance (10kHz-100MHz) driving the conventional MOSFETs into sub-threshold operation regime. In this paper, we present an alternate ultra-low power computing architecture using Binary Decision Diagram based logic circuits implemented using Single Electron Transistors (SETs) operating in the Coulomb blockade regime with very low supply voltages. We evaluate the energy - performance tradeoff metrics of such BDD circuits using time domain Monte Carlo simulations and compare them with the energy-optimized CMOS logic circuits. Simulation results show that the proposed approach achieves better energy-delay characteristics than CMOS realizations.

MOSFET-like CNFET based logic gate library for low-power application: a comparative study

International Nuclear Information System (INIS)

Gowri Sankar, P. A.; Udhayakumar, K.

2014-01-01

The next generation of logic gate devices are expected to depend upon radically new technologies mainly due to the increasing difficulties and limitations of existing CMOS technology. MOSFET like CNFETs should ideally be the best devices to work with for high-performance VLSI. This paper presents results of a comprehensive comparative study of MOSFET-like carbon nanotube field effect transistors (CNFETs) technology based logic gate library for high-speed, low-power operation than conventional bulk CMOS libraries. It focuses on comparing four promising logic families namely: complementary-CMOS (C-CMOS), transmission gate (TG), complementary pass logic (CPL) and Domino logic (DL) styles are presented. Based on these logic styles, the proposed library of static and dynamic NAND-NOR logic gates, XOR, multiplexer and full adder functions are implemented efficiently and carefully analyzed with a test bench to measure propagation delay and power dissipation as a function of supply voltage. This analysis provides the right choice of logic style for low-power, high-speed applications. Proposed logic gates libraries are simulated using Synopsys HSPICE based on the standard 32 nm CNFET model. The simulation results demonstrate that, it is best to use C-CMOS logic style gates that are implemented in CNFET technology which are superior in performance compared to other logic styles, because of their low average power-delay-product (PDP). The analysis also demonstrates how the optimum supply voltage varies with logic styles in ultra-low power systems. The robustness of the proposed logic gate library is also compared with conventional and state-art of CMOS logic gate libraries. (semiconductor integrated circuits)

Recent Progress of Self-Powered Sensing Systems for Wearable Electronics.

Science.gov (United States)

Lou, Zheng; Li, La; Wang, Lili; Shen, Guozhen

2017-12-01

Wearable/flexible electronic sensing systems are considered to be one of the key technologies in the next generation of smart personal electronics. To realize personal portable devices with mobile electronics application, i.e., wearable electronic sensors that can work sustainably and continuously without an external power supply are highly desired. The recent progress and advantages of wearable self-powered electronic sensing systems for mobile or personal attachable health monitoring applications are presented. An overview of various types of wearable electronic sensors, including flexible tactile sensors, wearable image sensor array, biological and chemical sensor, temperature sensors, and multifunctional integrated sensing systems is provided. Self-powered sensing systems with integrated energy units are then discussed, separated as energy harvesting self-powered sensing systems, energy storage integrated sensing systems, and all-in-on integrated sensing systems. Finally, the future perspectives of self-powered sensing systems for wearable electronics are discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Inorganic Lead Halide Perovskite Single Crystals: Phase-Selective Low-Temperature Growth, Carrier Transport Properties, and Self-Powered Photodetection

KAUST Repository

Saidaminov, Makhsud I.

2016-12-06

A rapid, low-temperature, and solution-based route is developed for growing large-sized cesium lead halide perovskite single crystals under ambient conditions. An ultralow minority carrier concentration was measured in CsPbBr3 (≈108 holes per cm3, much lower than in any other lead halide perovskite and crystalline silicon), which enables to realize self-powered photodetectors with a high ON/OFF ratio (105).

Ultra low-power biomedical signal processing: An analog wavelet filter approach for pacemakers

OpenAIRE

Pavlík Haddad, S.A.

2006-01-01

The purpose of this thesis is to describe novel signal processing methodologies and analog integrated circuit techniques for low-power biomedical systems. Physiological signals, such as the electrocardiogram (ECG), the electroencephalogram (EEG) and the electromyogram (EMG) are mostly non-stationary. The main difficulty in dealing with biomedical signal processing is that the information of interest is often a combination of features that are well localized temporally (e.g., spikes) and other...

A new self-scheduling strategy for integrated operation of wind and pumped-storage power plants in power markets

International Nuclear Information System (INIS)

Varkani, Ali Karimi; Daraeepour, Ali; Monsef, Hassan

2011-01-01

Highlights: → A strategy for integrated operation of wind and pumped-storage plants is proposed. → Participation of both plants in energy and ancillary service markets is modeled. → The uncertainty of wind production is modeled by a novel probabilistic function. → The proposed strategy is tested on a real case in the Spanish electricity market. -- Abstract: Competitive structure of power markets causes various challenges for wind resources to participate in these markets. Indeed, production uncertainty is the main cause of their low income. Thus, they are usually supported by system operators, which is in contrast with the competitive paradigm of power markets. In this paper, a new strategy for increasing the profits of wind resources is proposed. In the suggested strategy, a Generation Company (GenCo), who owns both wind and pumped-storage plants, self-schedules the integrated operation of them regarding the uncertainty of wind power generation. For presenting an integrated self-schedule and obtaining a real added value of the strategy, participation of the GenCo in energy and ancillary service markets is modeled. The self-scheduling strategy is based on stochastic programming techniques. Outputs of the problem include generation offers in day-ahead energy market and ancillary service markets, including spinning and regulation reserve markets. A Neural Network (NN) based technique is used for modeling the uncertainty of wind power production. The proposed strategy is tested on a real wind farm in mainland, Spain. Moreover, added value of the strategy is presented in different conditions of the market.

Initial absolute calibration factors for some neutron sensitive self-powered detectors

International Nuclear Information System (INIS)

Kroon, J.

1975-01-01

Self-powered flux detectors have found extensive use as monitoring devices in PWR (Pressurized Water Reactor) cores and CANDU (Canada Deuterium Uranium) type power reactors. The detectors measure fuel power distributions and indicate trip parameters for reactor control and safety requirements. Both applications demand accurate absolute initial calibration factors. Experimental results obtained in calibrating some neutron sensitive self-powered detectors is presented. (author)

Implementing low power consumption in standby mode in the case of power supplies with power factor correction

OpenAIRE

Martín, Kevin; F., Pablo; G., Diego; Sebastián, Javier; Álvarez, Santiago

2017-01-01

This work analyzes different options to implement low power consumption in Switching Mode Power Supplies (SMPSs) with Power Factor Correction (PFC) when they are in standby mode. The standard SMPSs for power levels higher than 100 W are made up of two stages: a classical PFC stage based on a Boost Converter operating in the Continuous Conduction Mode and a second stage based on any type of isolated DC-DC converter. The value of the resistive sensors needed by the PFC control stage determines ...

A self-starting hybrid optoelectronic oscillator generating ultra low jitter 10-GHz optical pulses and low phase noise electrical signals

DEFF Research Database (Denmark)

Lasri, J.; Bilenca, A.; Dahan, D.

2002-01-01

In this letter, we describe a self-starting optical pulse source generating ultra low noise 15-ps-wide pulses at 10 GHz. It is based on a hybrid optoelectronic oscillator comprising a fiber extended cavity mode-locked diode laser which injection locks a self-oscillating heterojunction bipolar...

Operational flexibility and economics of power plants in future low-carbon power systems

NARCIS (Netherlands)

Brouwer, Anne Sjoerd; van den Broek, Machteld; Seebregts, Ad; Faaij, André

2015-01-01

Future power systems will require large shares of low-carbon generators such as renewables and power plants with Carbon Capture and Storage (CCS) to keep global warming below 2. °C. Intermittent renewables increase the system-wide demand for flexibility and affect the operation of thermal power

Device and Circuit Design Challenges in the Digital Subthreshold Region for Ultralow-Power Applications

Directory of Open Access Journals (Sweden)

Ramesh Vaddi

2009-01-01

Full Text Available In recent years, subthreshold operation has gained a lot of attention due to ultra low-power consumption in applications requiring low to medium performance. It has also been shown that by optimizing the device structure, power consumption of digital subthreshold logic can be further minimized while improving its performance. Therefore, subthreshold circuit design is very promising for future ultra low-energy sensor applications as well as high-performance parallel processing. This paper deals with various device and circuit design challenges associated with the state of the art in optimal digital subthreshold circuit design and reviews device design methodologies and circuit topologies for optimal digital subthreshold operation. This paper identifies the suitable candidates for subthreshold operation at device and circuit levels for optimal subthreshold circuit design and provides an effective roadmap for digital designers interested to work with ultra low-power applications.

Low-Power Implantable Device for Onset Detection and Subsequent Treatment of Epileptic Seizures: A Review

Directory of Open Access Journals (Sweden)

Muhammad Tariqus Salam

2010-01-01

Full Text Available Over the past few years, there has been growing interest in neuro-responsive intracerebral local treatments of seizures, such as focal drug delivery, focal cooling, or electrical stimulation. This mode of treatment requires an effective intracerebral electroencephalographic acquisition system, seizure detector, brain stimulator, and wireless system that consume ultra-low power. This review focuses on alternative brain stimulation treatments for medically intractable epilepsy patients. We mainly discuss clinical studies of long-term responsive stimulation and suggest safer optimized therapeutic options for epilepsy. Finally, we conclude our study with the proposed low-power, implantable fully integrated device that automatically detects low-voltage fast activity ictal onsets and triggers focal treatment to disrupt seizure progression. The detection performance was verified using intracerebral electroencephalographic recordings from two patients with epilepsy. Further experimental validation of this prototype is underway.

Position-insensitive long range inductive power transfer

International Nuclear Information System (INIS)

Kwan, Christopher H; Lawson, James; Yates, David C; Mitcheson, Paul D

2014-01-01

This paper presents results of an improved inductive wireless power transfer system for reliable long range powering of sensors with milliwatt-level consumption. An ultra-low power flyback impedance emulator operating in open loop is used to present the optimal load to the receiver's resonant tank. Transmitter power modulation is implemented in order to maintain constant receiver power and to prevent damage to the receiver electronics caused by excessive received voltage. Received power is steady up to 3 m at around 30 mW. The receiver electronics and feedback system consumes 3.1 mW and so with a transmitter input power of 163.3 W the receiver becomes power neutral at 4.75 m. Such an IPT system can provide a reliable alternative to energy harvesters for supplying power concurrently to multiple remote sensors

Power budget of direct-detection ultra-dense WDM-Nyquist-SCM PON with low-complexity SSBI mitigation

Science.gov (United States)

Soeiro, Ricardo O. J.; Alves, Tiago M. F.; Cartaxo, Adolfo V. T.

2017-07-01

The power budget (PB) of a direct-detection ultra-dense wavelength division/subcarrier multiplexing (SCM) passive optical network (PON) is assessed numerically for downstream, when a low-complexity iterative signal-to-signal beat interference (SSBI) mitigation technique is employed. Each SCM signal, inserted in a 12.5 GHz width optical channel, is comprised of two or three electrically generated and multiplexed 16-quadrature-amplitude-modulation (QAM) or 32-QAM Nyquist pulse-shaped subcarriers, each with a 7% forward error correction bit rate of 10.7 Gbit/s. The PB and maximum number of optical network units (ONUs) served by each optical line terminal (OLT) are compared with and without SSBI mitigation. When SSBI mitigation is realized, PB gains up to 4.5 dB are attained relative to the PB in the absence of SSBI mitigation. The PB gain enabled by the SSBI mitigation technique proposed in this work increases the number of ONUs served per OLT at least by a factor of 2, for the cases of higher spectral efficiency. In particular, for a SCM signal comprised of three subcarriers, the maximum number of ONUs served per OLT is between 2 and 32, and between 8 and 64, in the absence of SSBI mitigation, and when SSBI mitigation is employed, respectively, depending on the fiber length (up to 50 km) and order of QAM.

Self-SALP/self-assessment at Calvert Cliffs nuclear power plant

International Nuclear Information System (INIS)

Pieringer, P.; Slider, J.E.

1992-01-01

In recent years, utilities have undertaken various forms of self-assessment. These methods have as their goal early detection of weaknesses in plan performance to permit timely corrective action. Ideally, self-assessment methods identify problems at a lower threshold than do outside agencies, such as the US Nuclear Regulatory Commission (NRC) and the Institute of Nuclear Power Operations (INPO). One of the more popular methods of self-assessment has been the self-SALP (systematic assessment of licensee performance). This method emulates the procedures of the NRC's SALP to render a subjective, overall assessment of performance. The experience of Baltimore Gas and Electric Company (BG and E) in applying self-SALP methods at its Calvert Cliffs nuclear power plant (CCNPP) provides insights useful to other utilities considering use of self-SALP methods. The factors leading to BG and E's decision to use a different approach may help others evaluate their self-assessment choices. This paper summarizes BG and E's experience with self-SALP methods and describes the methods that will be used to evaluate performance in the future

High power passive μDMFC with low catalyst loading for small power generation

International Nuclear Information System (INIS)

Ahmad, M.M.; Kamarudin, S.K.; Daud, W.R.W.; Yaakub, Z.

2010-01-01

The main constraint for commercialization of micro direct methanol fuel cell (μDMFC) for small power generation is the performance of the fuel cell. In this study, a high power μDMFC with a power output of 56 mW and an active area of 4 cm 2 was successfully developed. The cell required low catalyst loading of 5 mg cm -2 and 0.5 mg cm -2 at the anode and cathode, respectively. Optimal design parameters for methanol concentration and catalyst loading were examined. Finally, long-term performance testing was performed and OCV curves are reported. The results obtained for this gives the highest power density at low catalyst loading as compare to other researchers in this area.

Power generation from low-temperature heat source

Energy Technology Data Exchange (ETDEWEB)

Lakew, Amlaku Abie

2012-07-01

The potential of low-temperature heat sources for power production has been discussed for decades. The diversity and availability of low-temperature heat sources makes it interesting for power production. The thermodynamic power cycle is one of the promising technologies to produce electricity from low-temperature heat sources. There are different working fluids to be used in a thermodynamic power cycle. Working fluid selection is essential for the performance of the power cycle. Over the last years, different working fluid screening criteria have been used. In broad speaking the screening criteria can be grouped as thermodynamic performance, component size requirement, economic performance, safety and environmental impact. Screening of working fluids at different heat source temperatures (80-200 Celsius degrees) using thermodynamic performance (power output and exergy efficiency) and component size (heat exchanger and turbine) is investigated. It is found that the 'best' working fluid depends on the criteria used and heat source temperature level. Transcritical power cycles using carbon dioxide as a working fluid is studied to produce power at 100 Celsius degrees. Carbon dioxide is an environmentally friendly refrigerant. The global warming potential of carbon dioxide is 1. Furthermore, because of its low critical temperature (31 Celsius degrees), carbon dioxide can operate in a transcritical power cycle for lower heat source temperatures. A transcritical configuration avoids the problem of pinching which otherwise would happened in subcritical power cycle. In the process, better temperature matching is achieved and more heat is extracted. Thermodynamic analysis of transcritical cycle is performed; it is found that there is an optimal operating pressure for highest net power output. The pump work is a sizable fraction of the work produced by the turbine. The effect of efficiency deterioration of the pump and the turbine is compared. When the

Paper-based supercapacitors for self-powered nanosystems.

Science.gov (United States)

Yuan, Longyan; Xiao, Xu; Ding, Tianpeng; Zhong, Junwen; Zhang, Xianghui; Shen, Yue; Hu, Bin; Huang, Yunhui; Zhou, Jun; Wang, Zhong Lin

2012-05-14

Energy storage on paper: paper-based, all-solid-state, and flexible supercapacitors were fabricated, which can be charged by a piezoelectric generator or solar cells and then discharged to power a strain sensor or a blue-light-emitting diode, demonstrating its efficient energy management in self-powered nanosystems. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Low-Power, Low-Voltage Analog to Digital ΣΔ

DEFF Research Database (Denmark)

Wismar, Ulrik Sørensen

2007-01-01

, and since long operation time is required, low supply voltage and low power consumption are of paramount importance. Consequently, various topologies have been compared to nd the most power ecient audio frequency modulator topology. Chapter 4 of this thesis compares power consumption of two of the most...... prevalent topologies, the single-loop modulator with integration in discrete time and the single-loop modulator with integration in continuous time. Both modulator topologies are with feedback, and all intermediate signals are in the voltage mode. Chapter 5 treats a modulator without feedback. Another...

Self-Powered Electrochemical Lactate Biosensing

Directory of Open Access Journals (Sweden)

Ankit Baingane

2017-10-01

Full Text Available This work presents the development and characterization of a self-powered electrochemical lactate biosensor for real-time monitoring of lactic acid. The bioanode and biocathode were modified with D-lactate dehydrogenase (D-LDH and bilirubin oxidase (BOD, respectively, to facilitate the oxidation and reduction of lactic acid and molecular oxygen. The bioelectrodes were arranged in a parallel configuration to construct the biofuel cell. This biofuel cell’s current–voltage characteristic was analyzed in the presence of various lactic acid concentrations over a range of 1–25 mM. An open circuit voltage of 395.3 mV and a short circuit current density of 418.8 µA/cm² were obtained when operating in 25 mM lactic acid. Additionally, a 10 pF capacitor was integrated via a charge pump circuit to the biofuel cell to realize the self-powered lactate biosensor with a footprint of 1.4 cm × 2 cm. The charge pump enabled the boosting of the biofuel cell voltage in bursts of 1.2–1.8 V via the capacitor. By observing the burst frequency of a 10 pF capacitor, the exact concentration of lactic acid was deduced. As a self-powered lactate sensor, a linear dynamic range of 1–100 mM lactic acid was observed under physiologic conditions (37 °C, pH 7.4 and the sensor exhibited an excellent sensitivity of 125.88 Hz/mM-cm2. This electrochemical lactate biosensor has the potential to be used for the real-time monitoring of lactic acid level in biological fluids.

Cadmium-emitter self-powered thermal neutron detector performance characterization & reactor power tracking capability experiments performed in ZED-2

Energy Technology Data Exchange (ETDEWEB)

LaFontaine, M.W., E-mail: physics@execulink.com [LaFontaine Consulting, Kitchener, Ontario (Canada); Zeller, M.B. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Nielsen, K. [Royal Military College of Canada, SLOWPOKE-2 Reactor, Kingston, Ontario (Canada)

2014-07-01

Cadmium-emitter self-powered thermal neutron flux detectors (SPDs), are typically used for flux monitoring and control applications in low temperature, test reactors such as the SLOWPOKE-2. A collaborative program between Atomic Energy of Canada, academia (Royal Military College of Canada (RMCC)) and industry (LaFontaine Consulting) was initiated to characterize the incore performance of a typical Cd-emitter SPD; and to obtain a definitive measure of the capability of the detector to track changes in reactor power in real time. Prior to starting the experiment proper, Chalk River Laboratories' ZED-2 was operated at low power (5 watts nominal) to verify the predicted moderator critical height. Test measurements were then performed with the vertical center of the SPD emitter positioned at the vertical mid-plane of the ZED-2 reactor core. Measurements were taken with the SPD located at lattice position L0 (near center), and repeated at lattice position P0 (in D{sub 2}O reflector). An ionization chamber (part of the ZED-2 control instrumentation) monitored reactor power at a position located on the south side of the outside wall of the reactor's calandria. These experiments facilitated measurement of the absolute thermal neutron sensitivity of the subject Cd-emitter SPD, and validated the power tracking capability of said SPD. Procedural details of the experiments, data, calculations and associated graphs, are presented and discussed. (author)

``Low Power Wireless Technologies: An Approach to Medical Applications''

Science.gov (United States)

Bellido O., Francisco J.; González R., Miguel; Moreno M., Antonio; de La Cruz F, José Luis

Wireless communication supposed a great both -quantitative and qualitative, jump in the management of the information, allowing the access and interchange of it without the need of a physical cable connection. The wireless transmission of voice and information has remained in constant evolution, arising new standards like BluetoothTM, WibreeTM or ZigbeeTM developed under the IEEE 802.15 norm. These newest wireless technologies are oriented to systems of communication of short-medium distance and optimized for a low cost and minor consume, becoming recognized as a flexible and reliable medium for data communications across a broad range of applications due to the potential that the wireless networks presents to operate in demanding environments providing clear advantages in cost, size, power, flexibility, and distributed intelligence. About the medical applications, the remote health or telecare (also called eHealth) is getting a bigger place into the manufacturers and medical companies, in order to incorporate products for assisted living and remote monitoring of health parameteres. At this point, the IEEE 1073, Personal Health Devices Working Group, stablish the framework for these kind of applications. Particularly, the 1073.3.X describes the physical and transport layers, where the new ultra low power short range wireless technologies can play a big role, providing solutions that allow the design of products which are particularly appropriate for monitor people’s health with interoperability requirements.

Design of a planar ultra-wideband four-way power divider/combiner using defected ground structures

DEFF Research Database (Denmark)

Squartecchia, Michele; Cimoli, Bruno; Midili, Virginio

2017-01-01

This work presents the design of a planar ultra-wideband (UWB) four-way power divider/combiner. A prototype has been fabricated on a printed circuit board and characterized. For achieving the frequency response required in UWB applications, each branch of the divider is conceived as a three...

Investigation of the response of improved self-powered neutron detectors

International Nuclear Information System (INIS)

Erk, S.

1982-01-01

The self-powered neutron detectors have been successfully employed for the most important parameters both for neutron flux and flux fluence determination. Their preference for such measurements due to their simplicity, convenience in use, rigidity, voluminal smallness and low price. However, self-powered neutron detectors depend on the type used, can only follow the neutron flux changes with a certain delay when they are compared to fission chambers which are thought to be the best detectors. In this thesis, a system has been proposed and considered carefully in order to speed up the response time, in another word, to correct the detector response to a level very near to fission chamber performance, a circuitry has been realized in the frame of principles so forth and applied to the experiments carried out in the TR-1 Reactor. Their positive results are presented. (author)

Scenarios for low carbon and low water electric power plant ...

Science.gov (United States)

In the water-energy nexus, water use for the electric power sector is critical. Currently, the operational phase of electric power production dominates the electric sector's life cycle withdrawal and consumption of fresh water resources. Water use associated with the fuel cycle and power plant equipment manufacturing phase is substantially lower on a life cycle basis. An outstanding question is: how do regional shifts to lower carbon electric power mixes affect the relative contribution of the upstream life cycle water use? To test this, we examine a range of scenarios comparing a baseline with scenarios of carbon reduction and water use constraints using the MARKet ALlocation (MARKAL) energy systems model with ORD's 2014 U.S. 9-region database (EPAUS9r). The results suggest that moving toward a low carbon and low water electric power mix may increase the non-operational water use. In particular, power plant manufacturing water use for concentrating solar power, and fuel cycle water use for biomass feedstock, could see sharp increases under scenarios of high deployment of these low carbon options. Our analysis addresses the following questions. First, how does moving to a lower carbon electricity generation mix affect the overall regional electric power water use from a life cycle perspective? Second, how does constraining the operational water use for power plants affect the mix, if at all? Third, how does the life cycle water use differ among regions under

Application of parallel connected power-MOSFET elements to high current d.c. power supply

International Nuclear Information System (INIS)

Matsukawa, Tatsuya; Shioyama, Masanori; Shimada, Katsuhiro; Takaku, Taku; Neumeyer, Charles; Tsuji-Iio, Shunji; Shimada, Ryuichi

2001-01-01

The low aspect ratio spherical torus (ST), which has single turn toroidal field coil, requires the extremely high d.c. current like as 20 MA to energize the coil. Considering the ratings of such extremely high current and low voltage, power-MOSFET element is employed as the switching device for the a.c./d.c. converter of power supply. One of the advantages of power-MOSFET element is low on-state resistance, which is to meet the high current and low voltage operation. Recently, the capacity of power-MOSFET element has been increased and its on-state resistance has been decreased, so that the possibility of construction of high current and low voltage a.c./d.c. converter with parallel connected power-MOSFET elements has been growing. With the aim of developing the high current d.c. power supply using power-MOSFET, the basic characteristics of parallel operation with power-MOSFET elements are experimentally investigated. And, the synchronous rectifier type and the bi-directional self commutated type a.c./d.c. converters using parallel connected power-MOSFET elements are proposed

Advancements of ultra-high peak power laser diode arrays

Science.gov (United States)

Crawford, D.; Thiagarajan, P.; Goings, J.; Caliva, B.; Smith, S.; Walker, R.

2018-02-01

Enhancements of laser diode epitaxy in conjunction with process and packaging improvements have led to the availability of 1cm bars capable of over 500W peak power at near-infrared wavelengths (770nm to 1100nm). Advances in cooler design allow for multi-bar stacks with bar-to-bar pitches as low as 350μm and a scalable package architecture enabled a single diode assembly with total peak powers of over 1MegaWatt of peak power. With the addition of micro-optics, overall array brightness greater than 10kW/cm2 was achieved. Performance metrics of barbased diode lasers specifically engineered for high peak power and high brightness at wavelengths and pulse conditions commonly used to pump a variety of fiber and solid-state materials are presented.

A Novel Low Power Bitcell Design Featuring Inherent SEU Prevention and Self Correction Capabilities

Directory of Open Access Journals (Sweden)

Oron Chertkow

2015-06-01

Full Text Available The pursuit of continuous scaling of electronic devices in the semiconductor industry has led to two unintended but significant outcomes: a rapid increase in susceptibility to radiation induced errors, and an overall rise in power consumption. Operating under low voltage to reduce power only aggravates radiation related reliability issues. The proposed “SEU Hardening Incorporating Extreme Low Power Bitcell Design” (SHIELD addresses these two major concerns simultaneously. It is based on the concept of gating the conventional cross-coupled inverters while introducing a novel “cut-off” network. This creates redundant storage nodes and eliminates the internal feedback loop during radiation particle impact. The SHIELD bitcell tolerates upsets with charge deposits over 1 pC. Simulations confirm its advantages in terms of leakage power, with more than twofold lower leakage currents than previous solutions when operated at a 700mV supply voltage in a 65 nm process. To validate the bitcell’s robustness, several test cases and special concerns, including multiple node upsets (MNU and half-select, are examined.

A novel high-performance self-powered ultraviolet photodetector: Concept, analytical modeling and analysis

Science.gov (United States)

Ferhati, H.; Djeffal, F.

2017-12-01

In this paper, a new MSM-UV-photodetector (PD) based on dual wide band-gap material (DM) engineering aspect is proposed to achieve high-performance self-powered device. Comprehensive analytical models for the proposed sensor photocurrent and the device properties are developed incorporating the impact of DM aspect on the device photoelectrical behavior. The obtained results are validated with the numerical data using commercial TCAD software. Our investigation demonstrates that the adopted design amendment modulates the electric field in the device, which provides the possibility to drive appropriate photo-generated carriers without an external applied voltage. This phenomenon suggests achieving the dual role of effective carriers' separation and an efficient reduce of the dark current. Moreover, a new hybrid approach based on analytical modeling and Particle Swarm Optimization (PSO) is proposed to achieve improved photoelectric behavior at zero bias that can ensure favorable self-powered MSM-based UV-PD. It is found that the proposed design methodology has succeeded in identifying the optimized design that offers a self-powered device with high-responsivity (98 mA/W) and superior ION/IOFF ratio (480 dB). These results make the optimized MSM-UV-DM-PD suitable for providing low cost self-powered devices for high-performance optical communication and monitoring applications.

High-power Yb-fiber comb based on pre-chirped-management self-similar amplification

Science.gov (United States)

Luo, Daping; Liu, Yang; Gu, Chenglin; Wang, Chao; Zhu, Zhiwei; Zhang, Wenchao; Deng, Zejiang; Zhou, Lian; Li, Wenxue; Zeng, Heping

2018-02-01

We report a fiber self-similar-amplification (SSA) comb system that delivers a 250-MHz, 109-W, 42-fs pulse train with a 10-dB spectral width of 85 nm at 1056 nm. A pair of grisms is employed to compensate the group velocity dispersion and third-order dispersion of pre-amplified pulses for facilitating a self-similar evolution and a self-phase modulation (SPM). Moreover, we analyze the stabilities and noise characteristics of both the locked carrier envelope phase and the repetition rate, verifying the stability of the generated high-power comb. The demonstration of the SSA comb at such high power proves the feasibility of the SPM-based low-noise ultrashort comb.

Research Update: Nanogenerators for self-powered autonomous wireless sensors

Science.gov (United States)

Khan, Usman; Hinchet, Ronan; Ryu, Hanjun; Kim, Sang-Woo

2017-07-01

Largely distributed networks of sensors based on the small electronics have great potential for health care, safety, and environmental monitoring. However, in order to have a maintenance free and sustainable operation, such wireless sensors have to be self-powered. Among various energies present in our environment, mechanical energy is widespread and can be harvested for powering the sensors. Piezoelectric and triboelectric nanogenerators (NGs) have been recently introduced for mechanical energy harvesting. Here we introduce the architecture and operational modes of self-powered autonomous wireless sensors. Thereafter, we review the piezoelectric and triboelectric NGs focusing on their working mechanism, structures, strategies, and materials.

Application of pulse power technology to ultra high energy electron accelerators

International Nuclear Information System (INIS)

Nation, J.A.

1989-01-01

The author presents in this paper a review of the application of pulse power technology to the development of high gradient electron accelerators. The technology demands are relatively modest compared to the ultra high power technology used for inertial confinement fusion drivers. With the advent of magnetic switching intense electron beams can be generated with a sufficiently high repetition rate to be of interest for high energy electron accelerator driver applications. Most of the techniques considered rely on the excitation of large amplitude waves on the beams. Within this framework there are two broad categories of accelerator, those in which the waves are directly excited in and supported by the medium and, secondly, those where the waves are used to generate radiofrequency signals which are then coupled via structures to the beam being accelerated. In what follows we shall consider both approaches. Present-day pulse power technology limits pulse durations to about 100 nsec. Consequently, if these sources are to be used, we will need to use high group velocity structures to avoid the need for short accelerator module lengths. An advantage of the short pulse duration is that the available acceleration voltage gradient increases compared to that obtained using conventional rf drivers. 19 references, 9 figures, 1 table

Low-Power Public Key Cryptography

Energy Technology Data Exchange (ETDEWEB)

BEAVER,CHERYL L.; DRAELOS,TIMOTHY J.; HAMILTON,VICTORIA A.; SCHROEPPEL,RICHARD C.; GONZALES,RITA A.; MILLER,RUSSELL D.; THOMAS,EDWARD V.

2000-11-01

This report presents research on public key, digital signature algorithms for cryptographic authentication in low-powered, low-computation environments. We assessed algorithms for suitability based on their signature size, and computation and storage requirements. We evaluated a variety of general purpose and special purpose computing platforms to address issues such as memory, voltage requirements, and special functionality for low-powered applications. In addition, we examined custom design platforms. We found that a custom design offers the most flexibility and can be optimized for specific algorithms. Furthermore, the entire platform can exist on a single Application Specific Integrated Circuit (ASIC) or can be integrated with commercially available components to produce the desired computing platform.

Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

Energy Technology Data Exchange (ETDEWEB)

Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil [' ' Dunarea de Jos' ' University of Galati, 47, Domneasca, 800008-Galati (Romania)

2010-02-15

This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results. (author)

Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

International Nuclear Information System (INIS)

Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil

2010-01-01

This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results.

Paper-based origami triboelectric nanogenerators and self-powered pressure sensors

KAUST Repository

Yang, Pokang

2015-01-27

Discovering renewable and sustainable power sources is indispensable for the development of green electronics and sensor networks. In this paper, we present origami triboelectric nanogenerators (TENGs) using paper as the starting material, with a high degree of flexibility, light weight, low cost, and recyclability. Slinky- and doodlebug-shaped TENGs can be easily fabricated by properly folding printer papers. The as-fabricated TENGs are capable of harvesting ambient mechanical energy from various kinds of human motions, such as stretching, lifting, and twisting. The generated electric outputs have been used to directly light-up commercial LEDs. In addition, the as-fabricated TENGs can also serve as self-powered pressure sensors.

An approach of raising the low power reactor trip block (P-7) in Maanshan Power Plant

International Nuclear Information System (INIS)

Wang, L.C.

1984-01-01

The technical specification for the Maanshan Nuclear Power Station (FSAR Table 16.2.2-3) requires that with an increasing reactor power level above the setpoint of low power reactor trip block (P-7), a turbine trip shall initiate a reactor trip. This anticipatory reactor trip on turbine trip prevents the pressurizer PORV from openning during turbine trip event. In order to reduce unnecessary reactor trip due to turbine trip on low reactor power level during Maanshan start-up stage, Taiwan Power Company performed a transient analysis for turbine trip event by using RETRAN code. The highest reactor power level at which a turbine trip will not open the pressurizer PORV is searched. The results demonstrated that this power level can be increased from the original value-10% of the rated thermal power-to about 48% of the rated thermal power

Microscale anechoic architecture: acoustic diffusers for ultra low power microparticle separation via traveling surface acoustic waves.

Science.gov (United States)

Behrens, Jan; Langelier, Sean; Rezk, Amgad R; Lindner, Gerhard; Yeo, Leslie Y; Friend, James R

2015-01-07

We present a versatile and very low-power traveling SAW microfluidic sorting device able to displace and separate particles of different diameter in aqueous suspension; the travelling wave propagates through the fluid bulk and diffuses via a Schröder diffuser, adapted from its typical use in concert hall acoustics to be the smallest such diffuser to be suitable for microfluidics. The effective operating power range is two to three orders of magnitude less than current SAW devices, uniquely eliminating the need for amplifiers, and by using traveling waves to impart forces directly upon suspended microparticles, they can be separated by size.

CORPORATE FEED WITH DUAL SEGMENT CIRCULAR POLARIZED ARRAY RECTENNA FOR LOW POWER RF ENERGY HARVESTING

Directory of Open Access Journals (Sweden)

CHIA CHAO KANG

2016-06-01

Full Text Available This paper focuses on the investigation of the level powers that can be scavenged from the ambient environment by using corporate feed with dual segment circular polarized antenna array . It will converts the received power to direct current (DC. Being a circular polarized antenna, it has higher inductance per unit area, a good Q-factor and compact capability. The design of corporate-series feed rectenna array is to achieve a high gain antenna and maximize the RF energy received by the rectenna system at ultra low power levels. The entire structure was investigated using a combination of harmonic balance nonlinear analysis and full wave electromagnetic field analysis. The results show that 5.0 dBi gain for circular polarized antenna array can be achieved at frequency 956 MHz. When the input power of 20 dBm fed into the transmitting antenna, the maximum distance for radio frequency (RF harvesting is 5.32m. The output DC voltage for various values of incident RF power is also presented. There are noticed reasonable agreements between the simulated and measured result and the works concludes that the investigation of RF energy harvesting system was successful.

Large Scale Triboelectric Nanogenerator and Self-Powered Flexible Sensor for Human Sleep Monitoring

Directory of Open Access Journals (Sweden)

Xiaoheng Ding

2018-05-01

Full Text Available The triboelectric nanogenerator (TENG and its application as a sensor is a popular research subject. There is demand for self-powered, flexible sensors with high sensitivity and high power-output for the next generation of consumer electronics. In this study, a 300 mm × 300 mm carbon nanotube (CNT-doped porous PDMS film was successfully fabricated wherein the CNT influenced the micropore structure. A self-powered TENG tactile sensor was established according to triboelectric theory. The CNT-doped porous TENG showed a voltage output seven times higher than undoped porous TENG and 16 times higher than TENG with pure PDMS, respectively. The TENG successfully acquired human motion signals, breath signals, and heartbeat signals during a sleep monitoring experiment. The results presented here may provide an effective approach for fabricating large-scale and low-cost flexible TENG sensors.

Self-Powered Neutron and Gamma Detectors for In-Core Measurements

International Nuclear Information System (INIS)

Strindehag, O.

1971-11-01

The performance of various types of self-powered neutron and gamma detectors intended for control and power distribution measurements in water cooled reactors is discussed. The self-powered detectors are compared with other types of in-core detectors and attention is paid to such properties as neutron and gamma sensitivity, high-temperature performance, burn-up rate and time of response. Also treated are the advantages and disadvantages of using gamma detector data for power distribution calculations instead of data from neutron detectors. With regard to neutron-sensitive detectors, results from several long-term experiments with vanadium and cobalt detectors are presented. The results include reliability and stability data for these two detector types and the Co build-up in cobalt detectors. Experimental results which reveal the fast response of cobalt detectors are presented, and the use of cobalt detectors in reactor safety systems is discussed. Experience of the design and installation of complete flux probes, electronic units and data processing systems for power reactors is reported. The investigation of gamma-sensitive detectors includes detectors with emitters of lead, zirconium, magnesium and Inconel. Measured gamma sensitivities from calibrations both in a reactor and in a gamma cell are given, and the signal levels of self-powered neutron and gamma detectors when applied to power reactors are compared

Self-Powered Neutron and Gamma Detectors for In-Core Measurements

Energy Technology Data Exchange (ETDEWEB)

Strindehag, O

1971-11-15

The performance of various types of self-powered neutron and gamma detectors intended for control and power distribution measurements in water cooled reactors is discussed. The self-powered detectors are compared with other types of in-core detectors and attention is paid to such properties as neutron and gamma sensitivity, high-temperature performance, burn-up rate and time of response. Also treated are the advantages and disadvantages of using gamma detector data for power distribution calculations instead of data from neutron detectors. With regard to neutron-sensitive detectors, results from several long-term experiments with vanadium and cobalt detectors are presented. The results include reliability and stability data for these two detector types and the Co build-up in cobalt detectors. Experimental results which reveal the fast response of cobalt detectors are presented, and the use of cobalt detectors in reactor safety systems is discussed. Experience of the design and installation of complete flux probes, electronic units and data processing systems for power reactors is reported. The investigation of gamma-sensitive detectors includes detectors with emitters of lead, zirconium, magnesium and Inconel. Measured gamma sensitivities from calibrations both in a reactor and in a gamma cell are given, and the signal levels of self-powered neutron and gamma detectors when applied to power reactors are compared

Deepening structural reform, and speeding up self-reliant nuclear power development

International Nuclear Information System (INIS)

Wang Binghua

2010-01-01

Combining the implementation practices of the strategy on self-reliant development of the third generation nuclear power plant, the paper set forth that speeding up self-reliant nuclear power development has strategic significance to the national economy and the people's livelihood, which need further deepening structural reform and nuclear power structural reform with an aim to enhance the international competitiveness of China's nuclear industry. (author)

An optimized low-power voltage controlled oscillator

Science.gov (United States)

Shah, Kriyang; Le, Hai Phuong; Singh, Jugdutt

2007-01-01

This paper presents an optimised low-power low-phase-noise Voltage Controlled Oscillator (VCO) for Bluetooth wireless applications. The system level design issues and tradeoffs related to Direct Conversion Receiver (DCR) and Low Intermediate Frequency (IF) architecture for Bluetooth are discussed. Subsequently, for a low IF architecture, the critical VCO performance parameters are derived from system specifications. The VCO presented in the paper is optimised by implementing a novel biasing circuit that employs two current mirrors, one at the top and the other one at the bottom of the cross-coupled complementary VCO, to give the exact replica of the current in both the arms of current mirror circuit. This approach, therefore, significantly reduces the system power consumption as well as improves the system performance. Results show that, the VCO consumes only 281μW of power at 2V supply. Its phase noise performance are -115dBc/Hz, -130dBc/Hz and -141dBc/Hz at the offset frequency of 1MHz, 3MHz and 5MHz respectively. Results indicate that 31% reduction in power consumption is achieved as compared to the traditional VCO design. These characteristics make the designed VCO a better candidate for Bluetooth wireless application where power consumption is the major issue.

Low-Carbon Economic Dispatching for Power Grid Integrated with Carbon Capture Power Plants and Wind Power System

Directory of Open Access Journals (Sweden)

Sheng Siqing

2015-01-01

Full Text Available Carbon emission characteristics of all kinds of power units are analyzed against the background of the low carbon economy. This paper introduces carbon trading in the dispatching model, gives full consideration to the benefit or cost of carbon emission and introduces carbon emission in the dispatching model as a decision variable so as to achieve the unity of the economy and the environmental protection of the dispatching model. A low carbon economic dispatching model is established based on multiple objectives, such as the lowest thermal power generation cost, the lowest carbon trading cost and the lowest carbon capture power plant operation cost. Load equalization, output constraint of power unit, ramping constraint, spinning reserve constraint and carbon capture efficiency constraint should be taken into account in terms of constraint conditions. The model is solved by the particle swarm optimization based on dynamic exchange and density distance. The fact that the introduction of carbon trading can effectively reduce the level of carbon emission and increase the acceptance level of wind power is highlighted through the comparison of the results of three models’ computational examples. With the carbon trading mechanism, carbon capture power plants with new technologies are able to give full play to the advantage of reducing carbon emission and wind curtailment so as to promote the development of the energy conservation and emission reduction technology and reduce the total cost of the dispatching system.

Self-Excited Single-Stage Power Factor Correction Driving Circuit for LED Lighting

Directory of Open Access Journals (Sweden)

Yong-Nong Chang

2014-01-01

Full Text Available This pa\tper proposes a self-excited single-stage high power factor LED lighting driving circuit. Being featured with power factor correction capability without needing any control devices, the proposed circuit structure is with low cost and suitable for commercial production. The power factor correction function is accomplished by using inductor in combination with a half-bridge quasi resonant converter to achieve active switching and yield out voltage regulation according to load requirement. Furthermore, the zero-voltage switching in the half-bridge converter can be attained to promote the overall performance efficiency of the proposed circuit. Finally, the validity and production availability of the proposed circuit will be verified as well.

The origin of power-law distributions in self-organized criticality

International Nuclear Information System (INIS)

Yang, C B

2004-01-01

The origin of power-law distributions in self-organized criticality is investigated by treating the variation of the number of active sites in the system as a stochastic process. An avalanche is then regarded as a first-return random-walk process in a one-dimensional lattice. Power-law distributions of the lifetime and spatial size are found when the random walk is unbiased with equal probability to move in opposite directions. This shows that power-law distributions in self-organized criticality may be caused by the balance of competitive interactions. At the mean time, the mean spatial size for avalanches with the same lifetime is found to increase in a power law with the lifetime. (letter to the editor)

Leader power and self-serving behavior : The moderating role of accountability

NARCIS (Netherlands)

Rus, Diana; van Knippenberg, Daan; Wisse, Barbara

This study explored whether accountability influences the relationship between power and leader self-serving behavior. Across three studies, using both experimental manipulations and individual difference measures, we found that accountability mitigated the effects of power on leader self-serving

Compact and Ultra-Low-Power 2.4 GHz LNA for On-body Communication Devices

DEFF Research Database (Denmark)

Ruaro, Andrea; Gülstorff, Steen; Jakobsen, Kaj Bjarne

2015-01-01

components. The noise figure is as low as 1.5 dB with an associated power gain of 6.2 dB while it consumes less than 1 mW drawn from a 1 V supply. The input third-order intercept point (IIP3) and the 1-dB compression point (P1dB) are −11 and −9 dBm, respectively. The input and output return loss are better...

Ultra-low-noise transition edge sensors for the SAFARI L-band on SPICA

Science.gov (United States)

Goldie, D. J.; Gao, J. R.; Glowacka, D. M.; Griffin, D. K.; Hijmering, R.; Khosropanah, P.; Jackson, B. D.; Mauskopf, P. D.; Morozov, D.; Murphy, J. A.; Ridder, M.; Trappe, N.; O'Sullivan, C.; Withington, S.

2012-09-01

The Far-Infrared Fourier transform spectrometer instrument SAFARI-SPICA which will operate with cooled optics in a low-background space environment requires ultra-sensitive detector arrays with high optical coupling efficiencies over extremely wide bandwidths. In earlier papers we described the design, fabrication and performance of ultra-low-noise Transition Edge Sensors (TESs) operated close to 100mk having dark Noise Equivalent Powers (NEPs) of order 4 × 10-19W/√Hz close to the phonon noise limit and an improvement of two orders of magnitude over TESs for ground-based applications. Here we describe the design, fabrication and testing of 388-element arrays of MoAu TESs integrated with far-infrared absorbers and optical coupling structures in a geometry appropriate for the SAFARI L-band (110 - 210 μm). The measured performance shows intrinsic response time τ ~ 11ms and saturation powers of order 10 fW, and a dark noise equivalent powers of order 7 × 10-19W/√Hz. The 100 × 100μm2 MoAu TESs have transition temperatures of order 110mK and are coupled to 320×320μm2 thin-film β-phase Ta absorbers to provide impedance matching to the incoming fields. We describe results of dark tests (i.e without optical power) to determine intrinsic pixel characteristics and their uniformity, and measurements of the optical performance of representative pixels operated with flat back-shorts coupled to pyramidal horn arrays. The measured and modeled optical efficiency is dominated by the 95Ω sheet resistance of the Ta absorbers, indicating a clear route to achieve the required performance in these ultra-sensitive detectors.

Critical power for self-focusing of optical beam in absorbing media

Science.gov (United States)

Qi, Pengfei; Zhang, Lin; Lin, Lie; Zhang, Nan; Wang, Yan; Liu, Weiwei

2018-04-01

Self-focusing effects are of central importance for most nonlinear optical effects. The critical power for self-focusing is commonly investigated theoretically without considering a material’s absorption. Although this is practicable for various materials, investigating the critical power for self-focusing in media with non-negligible absorption is also necessary, because this is the situation usually met in practice. In this paper, the simple analytical expressions describing the relationships among incident power, absorption coefficient and focal position are provided by a simple physical model based on the Fermat principle. Expressions for the absorption dependent critical power are also derived; these can play important roles in experimental and applied research on self-focusing-related nonlinear optical phenomena in absorbing media. Numerical results, based on the nonlinear wave equation—and which can predict experimental results perfectly—are also presented, and agree quantitatively with the analytical results proposed in this paper.

SELF-DETERMINATION AND POWER: A HUMAN-CENTRIC APPROACH TO THE INTERNATIONAL RELATIONS

Directory of Open Access Journals (Sweden)

Shameer Modongal

2017-05-01

Full Text Available This paper analyzes the importance of self-determination in international relations. It explains the puzzle why some small regions or group of people are ready to be small states by separating from big powerful states. The self-determination of a nation is preferable to the people than a military power of the large state. The military power of a state may not translate into a better life of people. So people’s empowerment cannot be treated the necessary outcome of state’s military power. When one group of people feel as marginalized in national policymaking and its implications, they show a secessionist tendency. This paper contends that people may prefer their ideology, identity and self-determination than the power of the state.

One for all: social power increases self-anchoring of traits, attitudes, and emotions.

Science.gov (United States)

Overbeck, Jennifer R; Droutman, Vitaliya

2013-08-01

We argue that powerful people tend to engage in social projection. Specifically, they self-anchor: They use the self as a reference point when judging others' internal states. In Study 1, which used a reaction-time paradigm, powerful people used their own traits as a reference when assessing the traits of group members, classifying group descriptors more quickly if they had previously reported that those terms described themselves. Study 2, which used a classic false-consensus paradigm, showed that powerful people believed that their group-related attitudes were shared by group members. Study 3 showed that more-powerful people relied more on their own state affect when judging other people's ambiguous emotional expressions. These results support our argument that power fosters self-anchoring, because powerful individuals are often called on to act as the representative face of their groups, and the association between power and representation prompts the heuristic use of the self to infer group properties.

A low-power multi port register file design using a low-swing strategy

International Nuclear Information System (INIS)

Yan Hao; Liu Yan; Hua Siliang; Wang Donghui; Hou Chaohuan

2012-01-01

A low-power register file is designed by using a low-swing strategy and modified NAND address decoders. The proposed low-swing strategy is based on the feedback scheme and uses dynamic logic to reduce the active feedback power. This method contains two parts: WRITE and READ strategy. In the WRITE low-swing scheme, the modified memory cell is used to support low-swing WRITE. The modified NAND decoder not only dissipates less power, but also enables a great deal of area reduction. Compared with the conventional single-ended register file, the low-swing strategy saves 34.5% and 51.15% bit-line power in WRITE and READ separately. The post simulation results indicate a 39.4% power improvement when the twelve ports are all busy. (semiconductor integrated circuits)

A CMOS power-efficient low-noise current-mode front-end amplifier for neural signal recording.

Science.gov (United States)

Wu, Chung-Yu; Chen, Wei-Ming; Kuo, Liang-Ting

2013-04-01

In this paper, a new current-mode front-end amplifier (CMFEA) for neural signal recording systems is proposed. In the proposed CMFEA, a current-mode preamplifier with an active feedback loop operated at very low frequency is designed as the first gain stage to bypass any dc offset current generated by the electrode-tissue interface and to achieve a low high-pass cutoff frequency below 0.5 Hz. No reset signal or ultra-large pseudo resistor is required. The current-mode preamplifier has low dc operation current to enhance low-noise performance and decrease power consumption. A programmable current gain stage is adopted to provide adjustable gain for adaptive signal scaling. A following current-mode filter is designed to adjust the low-pass cutoff frequency for different neural signals. The proposed CMFEA is designed and fabricated in 0.18-μm CMOS technology and the area of the core circuit is 0.076 mm(2). The measured high-pass cutoff frequency is as low as 0.3 Hz and the low-pass cutoff frequency is adjustable from 1 kHz to 10 kHz. The measured maximum current gain is 55.9 dB. The measured input-referred current noise density is 153 fA /√Hz , and the power consumption is 13 μW at 1-V power supply. The fabricated CMFEA has been successfully applied to the animal test for recording the seizure ECoG of Long-Evan rats.

Solar powered hydrogen generating facility and hydrogen powered vehicle fleet. Final technical report, August 11, 1994--January 6, 1997

Energy Technology Data Exchange (ETDEWEB)

Provenzano, J.J.

1997-04-01

This final report describes activities carried out in support of a demonstration of a hydrogen powered vehicle fleet and construction of a solar powered hydrogen generation system. The hydrogen generation system was permitted for construction, constructed, and permitted for operation. It is not connected to the utility grid, either for electrolytic generation of hydrogen or for compression of the gas. Operation results from ideal and cloudy days are presented. The report also describes the achievement of licensing permits for their hydrogen powered trucks in California, safety assessments of the trucks, performance data, and information on emissions measurements which demonstrate performance better than the Ultra-Low Emission Vehicle levels.

Self-powered neutron flux detector assembly

International Nuclear Information System (INIS)

Allan, C.J.; McIntyre, I.L.

1980-01-01

A self-powered neutron flux detector has both the central emitter electrode and its surrounding collector electrode made of inconel 600. The lead cables may also be made of inconel. Other nickel alloys, or iron, nickel, titamium, chromium, zirconium or their alloys may also be used for the electrodes

Self Powered Non-Dispersive Infra-Red CO{sub 2} Gas Sensor

Energy Technology Data Exchange (ETDEWEB)

Gibson, D R; MacGregor, C, E-mail: des@gassensing.co.uk [Gas Sensing Solutions Ltd, 60 Grayshill Road, Westfield North Courtyard, Glasgow G68 9HQ (United Kingdom)

2011-08-17

This paper describes a non-dispersive infra-red CO{sub 2} gas sensor, incorporating a mid-infra-red solid state light source/ detector combination, tuned to match the spectral absorption characteristic of CO{sub 2} gas. Injection moulded optics provide low cost manufacture. Continuous operation power consumption is < 3.5mW and pulsed mode with energy per measurement < 6mJ. Self powered operation using a solar cell is demonstrated together with wireless capability. Performance of two path length variants (20mm and 70mm) is described. The sensor shows invariant temperature output characteristic from -25 to 50 deg. C. Accuracy level is typically {+-}3% of reading.

How leaders self-regulate their task performance: evidence that power promotes diligence, depletion, and disdain.

Science.gov (United States)

DeWall, C Nathan; Baumeister, Roy F; Mead, Nicole L; Vohs, Kathleen D

2011-01-01

When leaders perform solitary tasks, do they self-regulate to maximize their effort, or do they reduce effort and conserve their resources? Our model suggests that power motivates self-regulation toward effective performance-unless the task is perceived as unworthy of leaders. Our 1st studies showed that power improves self-regulation and performance, even when resources for self-regulation are low (ego depletion). Additional studies showed that leaders sometimes disdain tasks they deem unworthy, by withholding effort (and therefore performing poorly). Ironically, during ego depletion, leaders skip the appraisal and, therefore, work hard regardless of task suitability, so that depleted leaders sometimes outperform nondepleted ones. Our final studies replicated these patterns with different tasks and even with simple manipulation of framing and perception of the same task (Experiment 5). Experiment 4 also showed that the continued high exertion of leaders when depleted takes a heavy toll, resulting in larger impairments later. The judicious expenditure of self-control resources among powerful people may help them prioritize their efforts to pursue their goals effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Adaptive reactive power control of PV power plants for improved power transfer capability under ultra-weak grid conditions

DEFF Research Database (Denmark)

Yang, Dongsheng; Wang, Xiongfei; Liu, Fangcheng

2017-01-01

The Photovoltaic (PV) power plants are usually deployed in remote areas with the high solar irradiance, and their power transfer capabilities can be greatly limited by the large impedance of long-distance transmission lines. This paper investigates first the power transfer limit of the PV power p...

Self-Biased Differential Rectifier with Enhanced Dynamic Range for Wireless Powering

KAUST Repository

Ouda, Mahmoud H.; Khalil, Waleed; Salama, Khaled N.

2016-01-01

A self-biased, cross-coupled, differential rectifier is proposed with enhanced power-conversion efficiency over an extended range of input power. A prototype is designed for UHF 433MHz RF power-harvesting applications and is implemented using 0.18μm

Ultra-Wideband Transceivers for Cochlear Implants

Directory of Open Access Journals (Sweden)

Reisenzahn Alexander

2005-01-01

Full Text Available Ultra-wideband (UWB radio offers low power consumption, low power spectral density, high immunity against interference, and other benefits, not only for consumer electronics, but also for medical devices. A cochlear implant (CI is an electronic hearing apparatus, requiring a wireless link through human tissue. In this paper we propose an UWB link for a data rate of Mbps and a propagation distance up to 500 mm. Transmitters with step recovery diode and transistor pulse generators are proposed. Two types of antennas and their filter characteristics in the UWB spectrum will be discussed. An ultra-low-power back tunnel diode receiver prototype is described and compared with conventional detector receivers.

A pulse amplitude discriminator with very low-power consuming

International Nuclear Information System (INIS)

Deng Changming; Liu Zhengshan; Zhang Zhiyong; Cheng Chang

2000-01-01

A low-power pulse amplitude discriminator is described. The discriminator circuit is mainly composed of an integrated voltage comparator, MAX921, and owns the characters of very low-power and low operating voltage

Low-power analog integrated circuits for wireless ECG acquisition systems.

Science.gov (United States)

Tsai, Tsung-Heng; Hong, Jia-Hua; Wang, Liang-Hung; Lee, Shuenn-Yuh

2012-09-01

This paper presents low-power analog ICs for wireless ECG acquisition systems. Considering the power-efficient communication in the body sensor network, the required low-power analog ICs are developed for a healthcare system through miniaturization and system integration. To acquire the ECG signal, a low-power analog front-end system, including an ECG signal acquisition board, an on-chip low-pass filter, and an on-chip successive-approximation analog-to-digital converter for portable ECG detection devices is presented. A quadrature CMOS voltage-controlled oscillator and a 2.4 GHz direct-conversion transmitter with a power amplifier and upconversion mixer are also developed to transmit the ECG signal through wireless communication. In the receiver, a 2.4 GHz fully integrated CMOS RF front end with a low-noise amplifier, differential power splitter, and quadrature mixer based on current-reused folded architecture is proposed. The circuits have been implemented to meet the specifications of the IEEE 802.15.4 2.4 GHz standard. The low-power ICs of the wireless ECG acquisition systems have been fabricated using a 0.18 μm Taiwan Semiconductor Manufacturing Company (TSMC) CMOS standard process. The measured results on the human body reveal that ECG signals can be acquired effectively by the proposed low-power analog front-end ICs.

Ultralight Cut-Paper-Based Self-Charging Power Unit for Self-Powered Portable Electronic and Medical Systems.

Science.gov (United States)

Guo, Hengyu; Yeh, Min-Hsin; Zi, Yunlong; Wen, Zhen; Chen, Jie; Liu, Guanlin; Hu, Chenguo; Wang, Zhong Lin

2017-05-23

The development of lightweight, superportable, and sustainable power sources has become an urgent need for most modern personal electronics. Here, we report a cut-paper-based self-charging power unit (PC-SCPU) that is capable of simultaneously harvesting and storing energy from body movement by combining a paper-based triboelectric nanogenerator (TENG) and a supercapacitor (SC), respectively. Utilizing the paper as the substrate with an assembled cut-paper architecture, an ultralight rhombic-shaped TENG is achieved with highly specific mass/volume charge output (82 nC g -1 /75 nC cm -3 ) compared with the traditional acrylic-based TENG (5.7 nC g -1 /5.8 nC cm -3 ), which can effectively charge the SC (∼1 mF) to ∼1 V in minutes. This wallet-contained PC-SCPU is then demonstrated as a sustainable power source for driving wearable and portable electronic devices such as a wireless remote control, electric watch, or temperature sensor. This study presents a potential paper-based portable SCPU for practical and medical applications.

The influence of surface chemistry and size of nanoscale graphene oxide on photothermal therapy of cancer using ultra-low laser power.

Science.gov (United States)

Yang, Kai; Wan, Jianmei; Zhang, Shuai; Tian, Bo; Zhang, Youjiu; Liu, Zhuang

2012-03-01

Photothermal therapy as a physical treatment approach to destruct cancer has emerged as an alternative of currently used cancer therapies. Previously we have shown that polyethylene glycol (PEG) functionalized nano-graphene oxide (nGO-PEG) with strong optical absorption in the near-infrared (NIR) region was a powerful photothermal agent for in vivo cancer treatment. In this work, by using ultra-small reduced graphene oxide (nRGO) with non-covalent PEG coating, we study how sizes and surface chemistry affect the in vivo behaviors of graphene, and remarkably improve the performance of graphene-based in vivo photothermal cancer treatment. Owing to the enhanced NIR absorbance and highly efficient tumor passive targeting of nRGO-PEG, excellent in vivo treatment efficacy with 100% of tumor elimination is observed after intravenous injection of nRGO-PEG and the followed 808 nm laser irradiation, the power density (0.15 W/cm(2), 5 min) of which is an order of magnitude lower than that usually applied for in vivo tumor ablation using many other nanomaterials. All mice after treatment survive over a period of 100 days without a single death or any obvious sign of side effect. Our results highlight that both surface chemistry and sizes are critical to the in vivo performance of graphene, and show the promise of using optimized nano-graphene for ultra-effective photothermal treatment, which may potentially be combined with other therapeutic approaches to assist our fight against cancer. Copyright © 2011 Elsevier Ltd. All rights reserved.

Ultra-Low Voltage Class AB Switched Current Memory Cell

DEFF Research Database (Denmark)

Igor, Mucha

1996-01-01

This paper presents the theoretical basis for the design of class AB switched current memory cells employing floating-gate MOS transistors, suitable for ultra-low-voltage applications. To support the theoretical assumptions circuits based on these cells were designed using a CMOS process with thr......This paper presents the theoretical basis for the design of class AB switched current memory cells employing floating-gate MOS transistors, suitable for ultra-low-voltage applications. To support the theoretical assumptions circuits based on these cells were designed using a CMOS process...... with threshold voltages of 0.9V. Both hand calculations and PSPICE simulations showed that the cells designed allowed a maximum signal range better than +/-13 micoamp, with a supply voltage down to 1V and a quiescent bias current of 1 microamp, resulting in a very high current efficiency and effective power...

Low Power system Design techniques for mobile computers

NARCIS (Netherlands)

Havinga, Paul J.M.; Smit, Gerardus Johannes Maria

1997-01-01

Portable products are being used increasingly. Because these systems are battery powered, reducing power consumption is vital. In this report we give the properties of low power design and techniques to exploit them on the architecture of the system. We focus on: min imizing capacitance, avoiding

Low Power Consumption Wireless Sensor Communication System Integrated with an Energy Harvesting Power Source

OpenAIRE

Vlad MARSIC; Alessandro GIULIANO; Meiling ZHU

2013-01-01

This paper presents the testing results of a wireless sensor communication system with low power consumption integrated with an energy harvesting power source. The experiments focus on the system’s capability to perform continuous monitoring and to wirelessly transmit the data acquired from the sensors to a user base station, for realization of completely battery-free wireless sensor system. Energy harvesting technologies together with system design optimization for power consumption minimiza...

Delay-Limited Capacity in the Low Power Regime

KAUST Repository

Rezki, Zouheir

2016-02-11

Outage performance of the M-block fading with additive white Gaussian noise (BF-AWGN) is investigated in the low-power regime. We consider delay-constrained constant-rate communications with perfect channel state information (CSI) at both the transmitter and the receiver (CSI-TR), under a shortterm power constraint (STPC) and a long-term power constraint (LTPC). Subject to STPC, we show that selection diversity that allocates all the power to the strongest block is asymptotically optimal. Then, we provide a simple characterization of the outage probability in the regime of interest. We quantify the reward due to CSI-TR over the constant-rate constant-power scheme and show that this reward increases with the delay constraint. For instance, for Rayleigh fading, we find that a power gain up to 4.3 dB is achievable. Subject to LTPC, we show that the above guidelines still holds and that the outage performance improves due to the flexibility of the LTPC over the STPC. More interestingly, we prove that LTPC allows zero-outage communication even at low SNR and characterize the delaylimited capacity at low SNR in a simple form. More precisely, we establish that the delay-limited capacity scales linearly with the power constraint, for a given M < 1. Our framework highlights the benefit of fading at low SNR as the delay-limited capacity may outperform the AWGN capacity. For instance, for Rayleigh fading and with M = 3, the delay-limited capacity is 16% higher than the capacity of an AWGN channel.

Self-Powered Safety Helmet Based on Hybridized Nanogenerator for Emergency.

Science.gov (United States)

Jin, Long; Chen, Jun; Zhang, Binbin; Deng, Weili; Zhang, Lei; Zhang, Haitao; Huang, Xi; Zhu, Minhao; Yang, Weiqing; Wang, Zhong Lin

2016-08-23

The rapid development of Internet of Things and the related sensor technology requires sustainable power sources for their continuous operation. Scavenging and utilizing the ambient environmental energy could be a superior solution. Here, we report a self-powered helmet for emergency, which was powered by the energy converted from ambient mechanical vibration via a hybridized nanogenerator that consists of a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG). Integrating with transformers and rectifiers, the hybridized nanogenerator can deliver a power density up to 167.22 W/m(3), which was demonstrated to light up 1000 commercial light-emitting diodes (LEDs) instantaneously. By wearing the developed safety helmet, equipped with rationally designed hybridized nanogenerator, the harvested vibration energy from natural human motion is also capable of powering a wireless pedometer for real-time transmitting data reporting to a personal cell phone. Without adding much extra weight to a commercial one, the developed wearing helmet can be a superior sustainable power source for explorers, engineers, mine-workers under well, as well as and disaster-relief workers, especially in remote areas. This work not only presents a significant step toward energy harvesting from human biomechanical movement, but also greatly expands the applicability of TENGs as power sources for self-sustained electronics.

Self-Powered Neutron Detector Calibration Using a Large Vertical Irradiation Hole of HANARO

OpenAIRE

Kim Myong-Seop; Park Byung-Gun; Kang Gi-Doo

2018-01-01

A calibration technology of the self-powered neutron detectors (SPNDs) using a large vertical irradiation hole of HANARO is developed. The 40 Rh-SPNDs are installed on the polycarbonate plastic support, and the gold wires with the same length as the effective length of the rhodium emitter of the SPND are also installed to measure the neutron flux on the SPND. They are irradiated at a low reactor power, and the SPND current is measured using the pico-ammeter. The external gamma-rays which affe...

Out of control!? How loss of self-control influences prosocial behavior: the role of power and moral values.

Directory of Open Access Journals (Sweden)

Anne Joosten

Full Text Available Lack of self-control has been suggested to facilitate norm-transgressing behaviors because of the operation of automatic selfish impulses. Previous research, however, has shown that people having a high moral identity may not show such selfish impulses when their self-control resources are depleted. In the present research, we extended this effect to prosocial behavior. Moreover, we investigated the role of power in the interaction between moral identity and self-control depletion. More specifically, we expected that power facilitates the externalization of internal states, which implies that for people who feel powerful, rather than powerless, depletion decreases prosocial behavior especially for those low in moral identity. A laboratory experiment and a multisource field study supported our predictions. The present finding that the interaction between self-control depletion and moral identity is contingent upon people's level of power suggests that power may enable people to refrain from helping behavior. Moreover, the findings suggest that if organizations want to improve prosocial behaviors, it may be effective to situationally induce moral values in their employees.

Out of Control!? How Loss of Self-Control Influences Prosocial Behavior: The Role of Power and Moral Values

Science.gov (United States)

Joosten, Anne; van Dijke, Marius; Van Hiel, Alain; De Cremer, David

2015-01-01

Lack of self-control has been suggested to facilitate norm-transgressing behaviors because of the operation of automatic selfish impulses. Previous research, however, has shown that people having a high moral identity may not show such selfish impulses when their self-control resources are depleted. In the present research, we extended this effect to prosocial behavior. Moreover, we investigated the role of power in the interaction between moral identity and self-control depletion. More specifically, we expected that power facilitates the externalization of internal states, which implies that for people who feel powerful, rather than powerless, depletion decreases prosocial behavior especially for those low in moral identity. A laboratory experiment and a multisource field study supported our predictions. The present finding that the interaction between self-control depletion and moral identity is contingent upon people’s level of power suggests that power may enable people to refrain from helping behavior. Moreover, the findings suggest that if organizations want to improve prosocial behaviors, it may be effective to situationally induce moral values in their employees. PMID:26024380

A microfabricated low cost enzyme-free glucose fuel cell for powering low-power implantable devices

Science.gov (United States)

Oncescu, Vlad; Erickson, David

In the past decade the scientific community has showed considerable interest in the development of implantable medical devices such as muscle stimulators, neuroprosthetic devices, and biosensors. Those devices have low power requirements and can potentially be operated through fuel cells using reactants present in the body such as glucose and oxygen instead of non-rechargeable lithium batteries. In this paper, we present a thin, enzyme-free fuel cell with high current density and good stability at a current density of 10 μA cm -2. A non-enzymatic approach is preferred because of higher long term stability. The fuel cell uses a stacked electrode design in order to achieve glucose and oxygen separation. An important characteristic of the fuel cell is that it has no membrane separating the electrodes, which results in low ohmic losses and small fuel cell volume. In addition, it uses a porous carbon paper support for the anodic catalyst layer which reduces the amount of platinum or other noble metal catalysts required for fabricating high surface area electrodes with good reactivity. The peak power output of the fuel cell is approximately 2 μW cm -2 and has a sustainable power density of 1.5 μW cm -2 at 10 μA cm -2. An analysis on the effects of electrode thickness and inter electrode gap on the maximum power output of the fuel cell is also performed.

The essential tension between leadership and power: when leaders sacrifice group goals for the sake of self-interest.

Science.gov (United States)

Maner, Jon K; Mead, Nicole L

2010-09-01

Throughout human history, leaders have been responsible for helping groups attain important goals. Ideally, leaders use their power to steer groups toward desired outcomes. However, leaders can also use their power in the service of self-interest rather than effective leadership. Five experiments identified factors within both the person and the social context that determine whether leaders wield their power to promote group goals versus self-interest. In most cases, leaders behaved in a manner consistent with group goals. However, when their power was tenuous due to instability within the hierarchy, leaders high (but not low) in dominance motivation prioritized their own power over group goals: They withheld valuable information from the group, excluded a highly skilled group member, and prevented a proficient group member from having any influence over a group task. These self-interested actions were eliminated when the group was competing against a rival outgroup. Findings provide important insight into factors that influence the way leaders navigate the essential tension between leadership and power. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Transforming Ordinary Buildings into Smart Buildings via Low-Cost, Self-Powering Wireless Sensors & Sensor Networks

Energy Technology Data Exchange (ETDEWEB)

Feng, Philip [Case Western Reserve Univ., Cleveland, OH (United States)

2017-06-09

The research objective of this project is to design and demonstrate a low-cost, compact, easy-to-deploy, maintenance-free sensor node technology, and a network of such sensors, which enable the monitoring of multiphysical parameters and can transform today’s ordinary buildings into smart buildings with environmental awareness. We develop the sensor node and network via engineering and integration of existing technologies, including high-efficiency mechanical energy harvesting, and ultralow-power integrated circuits (ICs) for sensing and wireless communication. Through integration and innovative power management via specifically designed low-power control circuits for wireless sensing applications, and tailoring energy-harvesting components to indoor applications, the target products will have smaller volume, higher efficiency, and much lower cost (in both manufacturing and maintenance) than the baseline technology. Our development and commercialization objective is to create prototypes for our target products under the CWRU-Intwine collaboration.

Conceptual Study for development of a low power research reactor

International Nuclear Information System (INIS)

Park, C.; Kim, H. S.; Park, J. H.; Chae, H. T.; Lee, B. C.

2013-01-01

Even though the nuclear society is again facing with difficult situations after Fukusima accident, some countries still continues to consider nuclear power as one option of national energy sources and to introduce nuclear energy. As a research reactor has been regarded as a step-stone to establish infrastructures for the nuclear power development program, some countries that have plan to introduce the nuclear power energy are considering to construct a research reactor. Particularly, a low power research reactor whose main purpose is basic researches on the nuclear technology and education/training would be of interest to developing countries when taking the economy and level of science and technology into consideration. And many low power research reactors at operation are obsolescent and their numbers are decreasing. Hence, some concepts on a low power research reactor are being studied for the future needs. This paper presents the conceptual study on the basic requirements and the preliminary design features of a low power research reactor

Perspectives on Low Power and Shutdown Risk

International Nuclear Information System (INIS)

Camp, Allen L.; Whitehead, Donnie W.; Wheeler, Timothy A.; Lehner, John; Chu, Tsong-Lun; Lois, Erasmai; Drouin, Mary

2000-01-01

This paper presents results from a program sponsored by the US Nuclear Regulatory Commission to examine the risks from low power and shutdown operations. Significant progress has been made by the industry in reducing such risks; however, important operational events continue to occur. Current perceptions of low power and shutdown risks are discussed in the paper along with an assessment of the current methods for understanding important events and quantifying their associated risk

The effects of power on prosocial outcomes: a self-validation analysis

OpenAIRE

DeMarree, Kenneth G.; Petty, Richard E.; Briñol Turnes, Pablo

2012-01-01

The present research distinguishes between primary (cognitive) and secondary (metacognitive) processes in the domain of power. Power is a central construct in economic decision making, influencing people’s thoughts and behavior in organizational, political, consumer, and interpersonal contexts. Whereas most research has discussed ways that power can influence primary cognition (e.g., increased self-focused thoughts, heuristic processing), we examine how power can influence secondary cognition...

Passive and Self-Powered Autonomous Sensors for Remote Measurements

Directory of Open Access Journals (Sweden)

Mauro Serpelloni

2009-02-01

Full Text Available Autonomous sensors play a very important role in the environmental, structural, and medical fields. The use of this kind of systems can be expanded for several applications, for example in implantable devices inside the human body where it is impossible to use wires. Furthermore, they enable measurements in harsh or hermetic environments, such as under extreme heat, cold, humidity or corrosive conditions. The use of batteries as a power supply for these devices represents one solution, but the size, and sometimes the cost and unwanted maintenance burdens of replacement are important drawbacks. In this paper passive and self-powered autonomous sensors for harsh or hermetical environments without batteries are discussed. Their general architectures are presented. Sensing strategies, communication techniques and power management are analyzed. Then, general building blocks of an autonomous sensor are presented and the design guidelines that such a system must follow are given. Furthermore, this paper reports different proposed applications of autonomous sensors applied in harsh or hermetic environments: two examples of passive autonomous sensors that use telemetric communication are proposed, the first one for humidity measurements and the second for high temperatures. Other examples of self-powered autonomous sensors that use a power harvesting system from electromagnetic fields are proposed for temperature measurements and for airflow speeds.

Passive and self-powered autonomous sensors for remote measurements.

Science.gov (United States)

Sardini, Emilio; Serpelloni, Mauro

2009-01-01

Autonomous sensors play a very important role in the environmental, structural, and medical fields. The use of this kind of systems can be expanded for several applications, for example in implantable devices inside the human body where it is impossible to use wires. Furthermore, they enable measurements in harsh or hermetic environments, such as under extreme heat, cold, humidity or corrosive conditions. The use of batteries as a power supply for these devices represents one solution, but the size, and sometimes the cost and unwanted maintenance burdens of replacement are important drawbacks. In this paper passive and self-powered autonomous sensors for harsh or hermetical environments without batteries are discussed. Their general architectures are presented. Sensing strategies, communication techniques and power management are analyzed. Then, general building blocks of an autonomous sensor are presented and the design guidelines that such a system must follow are given. Furthermore, this paper reports different proposed applications of autonomous sensors applied in harsh or hermetic environments: two examples of passive autonomous sensors that use telemetric communication are proposed, the first one for humidity measurements and the second for high temperatures. Other examples of self-powered autonomous sensors that use a power harvesting system from electromagnetic fields are proposed for temperature measurements and for airflow speeds.

Radiation Tolerant Low Power Precision Time Source, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The availability of small, low power atomic clocks is now a reality for ground-based and airborne navigation systems. Kernco's Low Power Precision Time Source...

Graphene electric double layer capacitor with ultra-high-power performance

International Nuclear Information System (INIS)

Miller, John R.; Outlaw, R.A.; Holloway, B.C.

2011-01-01

We have demonstrated, for the first time, efficient 120 Hz filtering by an electric double layer capacitor (EDLC). The key to this ultra-high-power performance is electrodes made from vertically oriented graphene nanosheets grown directly on metal current collectors. This design minimized both electronic and ionic resistance and produced capacitors having RC time-constants of less than 200 μs. Significantly, graphene nanosheets have a preponderance of exposed edge planes that greatly increase stored charge over designs relying on basal plane surfaces. Collectively these factors make vertically oriented graphene nanosheet electrodes ideally suited for producing high-frequency EDLCs. Capacitors constructed with these electrodes are predicted to be significantly smaller than aluminum electrolyte capacitors that they could functionally replace plus be manufactured using standard semiconductor process equipment, creating interesting commercial opportunities.

A Low-Power Integrated Humidity CMOS Sensor by Printing-on-Chip Technology

Directory of Open Access Journals (Sweden)

Chang-Hung Lee

2014-05-01

Full Text Available A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems.

A low-power integrated humidity CMOS sensor by printing-on-chip technology.

Science.gov (United States)

Lee, Chang-Hung; Chuang, Wen-Yu; Cowan, Melissa A; Wu, Wen-Jung; Lin, Chih-Ting

2014-05-23

A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene)/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems.

A Self-Powered and Flexible Organometallic Halide Perovskite Photodetector with Very High Detectivity

KAUST Repository

Leung, Siu

2018-01-10

Flexible and self-powered photodetectors (PDs) are highly desirable for applications in image sensing, smart building, and optical communications. In this paper, a self-powered and flexible PD based on the methylammonium lead iodide (CH3 NH3 PBI3 ) perovskite is demonstrated. Such a self-powered PD can operate even with irregular motion such as human finger tapping, which enables it to work without a bulky external power source. In addition, with high-quality CH3 NH3 PBI3 perovskite thin film fabricated with solvent engineering, the PD exhibits an impressive detectivity of 1.22 × 1013 Jones. In the self-powered voltage detection mode, it achieves a large responsivity of up to 79.4 V mW-1 cm-2 and a voltage response of up to ≈90%. Moreover, as the PD is made of flexible and transparent polymer films, it can operate under bending and functions at 360 ° of illumination. As a result, the self-powered, flexible, 360 ° omnidirectional perovskite PD, featuring high detectivity and responsivity along with real-world sensing capability, suggests a new direction for next-generation optical communications, sensing, and imaging applications.

Reviving Vibration Energy Harvesting and Self-Powered Sensing by a Triboelectric Nanogenerator

KAUST Repository

Chen, Jun

2017-10-10

Vibration energy harvesting and sensing is a traditional and growing research field in which various working mechanisms and designs have been developed for an improved performance. Relying on a coupling effect of contact electrification and electrostatic induction, in the past 5 years, triboelectric nanogenerator (TENG) has been applied as a fundamentally new technology to revive the field of vibration energy harvesting and self-powered sensing, especially for low-frequency vibrations such as human motion, automobile, machine, and bridge vibrations. The demonstrated instantaneous energy conversion efficiency of ∼70% and a total efficiency up to 85% distinguished TENG from traditional techniques. In this article, both TENG-enabled vibration energy harvesting and self-powered active sensing are comprehensively reviewed. Moving toward future development, problems pressing for solutions and onward research directions are also posed to deliver a coherent picture.

Study of methodology for low power/shutdown fire PSA

International Nuclear Information System (INIS)

Yan Zhen; Li Zhaohua; Li Lin; Song Lei

2014-01-01

As a risk assessment technology based on probability, the fire PSA is accepted abroad by nuclear industry in its application in the risk assessment for nuclear power plants. Based on the industry experience, the fire-induced impact on the plant safety during low power and shutdown operation cannot be neglected, therefore fire PSA can be used to assess the corresponding fire risk. However, there is no corresponding domestic guidance/standard as well as accepted analysis methodology up to date. Through investigating the latest evolvement on fire PSA during low power and shutdown operation, and integrating its characteristic with the corresponding engineering experience, an engineering methodology to evaluate the fire risk during low power and shutdown operation for nuclear power plant is established in this paper. In addition, an analysis demonstration as an example is given. (authors)

Underwater thrust and power generation using flexible piezoelectric composites: an experimental investigation toward self-powered swimmer-sensor platforms

International Nuclear Information System (INIS)

Erturk, Alper; Delporte, Ghislain

2011-01-01

Fiber-based flexible piezoelectric composites offer several advantages to use in energy harvesting and biomimetic locomotion. These advantages include ease of application, high power density, effective bending actuation, silent operation over a range of frequencies, and light weight. Piezoelectric materials exhibit the well-known direct and converse piezoelectric effects. The direct piezoelectric effect has received growing attention for low-power generation to use in wireless electronic applications while the converse piezoelectric effect constitutes an alternative to replace the conventional actuators used in biomimetic locomotion. In this paper, underwater thrust and electricity generation are investigated experimentally by focusing on biomimetic structures with macro-fiber composite piezoelectrics. Fish-like bimorph configurations with and without a passive caudal fin (tail) are fabricated and compared. The favorable effect of having a passive caudal fin on the frequency bandwidth is reported. The presence of a passive caudal fin is observed to bring the second bending mode close to the first one, yielding a wideband behavior in thrust generation. The same smart fish configuration is tested for underwater piezoelectric power generation in response to harmonic excitation from its head. Resonant piezohydroelastic actuation is reported to generate milli-newton level hydrodynamic thrust using milli-watt level actuation power input. The average actuation power requirement for generating a mean thrust of 19 mN at 6 Hz using a 10 g piezoelastic fish with a caudal fin is measured as 120 mW. This work also discusses the feasibility of thrust generation using the harvested energy toward enabling self-powered swimmer-sensor platforms with comparisons based on the capacity levels of structural thin-film battery layers as well as harvested solar and vibrational energy

Self-powered suspension criterion and energy regeneration implementation scheme of motor-driven active suspension

Science.gov (United States)

Yan, Shuai; Sun, Weichao

2017-09-01

Active suspension systems have advantages on mitigating the effects of vehicle vibration caused by road roughness, which are one of the most important component parts in influencing the performances of vehicles. However, high amount of energy consumption restricts the application of active suspension systems. From the point of energy saving, this paper presents a self-powered criterion of the active suspension system to judge whether a motor-driven suspension can be self-powered or not, and then a motor parameter condition is developed as a reference to design a self-powered suspension. An energy regeneration implementation scheme is subsequently proposed to make the active suspension which has the potential to be self-powered achieve energy-saving target in the real application. In this implementation scheme, operating electric circuits are designed based on different working status of the actuator and power source and it is realizable to accumulate energy from road vibration and supply energy to the actuator by switching corresponding electric circuits. To apply the self-powered suspension criterion and energy regeneration implementation scheme, an active suspension system is designed with a constrained H∞ controller and calculation results indicate that it has the capability to be self-powered. Simulation results show that the performances of the self-powered active suspension are nearly the same as those of the active suspension with an external energy source and can achieve energy regeneration at the same time.

Innovative Self-Powered and Self-Contained Sensor Array for Separation Detection, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The proposed innovation is a self-contained, self-powered, robust flight test sensor array for the determination of separation. The proposed system uses off the...

Self-powered detectors sensitivity determination

International Nuclear Information System (INIS)

Surkov, V.; Soares, A.J.

1994-01-01

The determination of the initial sensitivity of Self Powered Detectors (SPDs) was performed. Measurements of thermal, epithermal and to gamma flux sensitivities were made with Vanadium, Cobalt, Rhodium, Silver and Platinum SPDs and, when possible, the values are compared with the ones from the existing literature. The determination of neutron sensitivity was realized using the IEA-R1 Reactor from IPEN. The thermal and epithermal neutron flux were determined with bare and Cadmium covered activation foils. (GOLD). (author)

Design and analysis of a direct-drive wind power generator with ultra-high torque density

Science.gov (United States)

Jian, Linni; Shi, Yujun; Wei, Jin; Zheng, Yanchong

2015-05-01

In order to get rid of the nuisances caused by mechanical gearboxes, generators with low rated speed, which can be directly connected to wind turbines, are attracting increasing attention. The purpose of this paper is to propose a new direct-drive wind power generator (DWPG), which can offer ultra-high torque density. First, magnetic gear (MG) is integrated to achieve non-contact torque transmission and speed variation. Second, armature windings are engaged to achieve electromechanical energy conversion. Interior permanent magnet (PM) design on the inner rotor is adopted to boost the torque transmission capability of the integrated MG. Nevertheless, due to lack of back iron on the stator, the proposed generator does not exhibit prominent salient feature, which usually exists in traditional interior PM (IPM) machines. This makes it with good controllability and high power factor as the surface-mounted permanent magnet machines. The performance is analyzed using finite element method. Investigation on the magnetic field harmonics demonstrates that the permanent-magnetic torque offered by the MG can work together with the electromagnetic torque offered by the armature windings to balance the driving torque captured by the wind turbine. This allows the proposed generator having the potential to offer even higher torque density than its integrated MG.

Prototypes of Self-Powered Radiation Detectors Employing Intrinsic High-Energy Current (HEC) (POSTPRINT)

Science.gov (United States)

2016-01-01

neutron sensi- tivities of a Pt self - powered detector ,” IEEE Trans. Nucl. Sci. 25, 292–295 (1978). 6T. A. Dellin, R. E. Huddleston, and C. J...Gamma-sensitive self - powered detectors and their use for in-core flux -mapping,” IEEE Trans. Nucl. Sci. 28, 752–757 (1981). 9E. A. Burke and J. Wall...AFCEC-CX-TY-TP-2016-0006 PROTOTYPES OF SELF - POWERED RADIATION DETECTORS EMPLOYING INTRINSIC HIGH-ENERGY CURRENT (HEC) (POSTPRINT) Piotr

A self-powered piezoelectric energy harvesting interface circuit with efficiency-enhanced P-SSHI rectifier

Science.gov (United States)

Liu, Lianxi; Pang, Yanbo; Yuan, Wenzhi; Zhu, Zhangming; Yang, Yintang

2018-04-01

The key to self-powered technique is initiative to harvest energy from the surrounding environment. Harvesting energy from an ambient vibration source utilizing piezoelectrics emerged as a popular method. Efficient interface circuits become the main limitations of existing energy harvesting techniques. In this paper, an interface circuit for piezoelectric energy harvesting is presented. An active full bridge rectifier is adopted to improve the power efficiency by reducing the conduction loss on the rectifying path. A parallel synchronized switch harvesting on inductor (P-SSHI) technique is used to improve the power extraction capability from piezoelectric harvester, thereby trying to reach the theoretical maximum output power. An intermittent power management unit (IPMU) and an output capacitor-less low drop regulator (LDO) are also introduced. Active diodes (AD) instead of traditional passive ones are used to reduce the voltage loss over the rectifier, which results in a good power efficiency. The IPMU with hysteresis comparator ensures the interface circuit has a large transient output power by limiting the output voltage ranges from 2.2 to 2 V. The design is fabricated in a SMIC 0.18 μm CMOS technology. Simulation results show that the flipping efficiency of the P-SSHI circuit is over 80% with an off-chip inductor value of 820 μH. The output power the proposed rectifier can obtain is 44.4 μW, which is 6.7× improvement compared to the maximum output power of a traditional rectifier. Both the active diodes and the P-SSHI help to improve the output power of the proposed rectifier. LDO outputs a voltage of 1.8 V with the maximum 90% power efficiency. The proposed P-SSHI rectifier interface circuit can be self-powered without the need for additional power supply. Project supported by the National Natural Science Foundation of China (Nos. 61574103, U1709218) and the Key Research and Development Program of Shaanxi Province (No. 2017ZDXM-GY-006).

Low Cost, Low Power, High Sensitivity Magnetometer

Science.gov (United States)

2008-12-01

which are used to measure the small magnetic signals from brain. Other types of vector magnetometers are fluxgate , coil based, and magnetoresistance...concentrator with the magnetometer currently used in Army multimodal sensor systems, the Brown fluxgate . One sees the MEMS fluxgate magnetometer is...Guedes, A.; et al., 2008: Hybrid - LOW COST, LOW POWER, HIGH SENSITIVITY MAGNETOMETER A.S. Edelstein*, James E. Burnette, Greg A. Fischer, M.G

76 FR 81998 - Methodology for Low Power/Shutdown Fire PRA

Science.gov (United States)

2011-12-29

... NUCLEAR REGULATORY COMMISSION [NRC-2011-0295] Methodology for Low Power/Shutdown Fire PRA AGENCY..., ``Methodology for Low Power/Shutdown Fire PRA--Draft Report for Comment.'' DATES: Submit comments by March 01... risk assessment (PRA) method for quantitatively analyzing fire risk in commercial nuclear power plants...

Self-channeling of high-power laser pulses through strong atmospheric turbulence

Science.gov (United States)

Peñano, J.; Palastro, J. P.; Hafizi, B.; Helle, M. H.; DiComo, G. P.

2017-07-01

We present an unusual example of truly long-range propagation of high-power laser pulses through strong atmospheric turbulence. A form of nonlinear self-channeling is achieved when the laser power is close to the self-focusing power of air and the transverse dimensions of the pulse are smaller than the coherence diameter of turbulence. In this mode, nonlinear self-focusing counteracts diffraction, and turbulence-induced spreading is greatly reduced. Furthermore, the laser intensity is below the ionization threshold so that multiphoton absorption and plasma defocusing are avoided. Simulations show that the pulse can propagate many Rayleigh lengths (several kilometers) while maintaining a high intensity. In the presence of aerosols, or other extinction mechanisms that deplete laser energy, the pulse can be chirped to maintain the channeling.

Ultra-Low Noise Germanium Neutrino Detection system (ULGeN).

Energy Technology Data Exchange (ETDEWEB)

Cabrera-Palmer, Belkis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Barton, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-07-01

Monitoring nuclear power plant operation by measuring the antineutrino flux has become an active research field for safeguards and non-proliferation. We describe various efforts to demonstrate the feasibility of reactor monitoring based on the detection of the Coherent Neutrino Nucleus Scattering (CNNS) process with High Purity Germanium (HPGe) technology. CNNS detection for reactor antineutrino energies requires lowering the electronic noise in low-capacitance kg-scale HPGe detectors below 100 eV as well as stringent reduction in other particle backgrounds. Existing state- of-the-art detectors are limited to an electronic noise of 95 eV-FWHM. In this work, we employed an ultra-low capacitance point-contact detector with a commercial integrated circuit preamplifier- on-a-chip in an ultra-low vibration mechanically cooled cryostat to achieve an electronic noise of 39 eV-FWHM at 43 K. We also present the results of a background measurement campaign at the Spallation Neutron Source to select the area with sufficient low background to allow a successful first-time measurement of the CNNS process.

Ultra-Low Noise Germanium Neutrino Detection system (ULGeN)

International Nuclear Information System (INIS)

Cabrera-Palmer, Belkis; Barton, Paul

2017-01-01

Monitoring nuclear power plant operation by measuring the antineutrino flux has become an active research field for safeguards and non-proliferation. We describe various efforts to demonstrate the feasibility of reactor monitoring based on the detection of the Coherent Neutrino Nucleus Scattering (CNNS) process with High Purity Germanium (HPGe) technology. CNNS detection for reactor antineutrino energies requires lowering the electronic noise in low-capacitance kg-scale HPGe detectors below 100 eV as well as stringent reduction in other particle backgrounds. Existing state- of-the-art detectors are limited to an electronic noise of 95 eV-FWHM. In this work, we employed an ultra-low capacitance point-contact detector with a commercial integrated circuit preamplifier- on-a-chip in an ultra-low vibration mechanically cooled cryostat to achieve an electronic noise of 39 eV-FWHM at 43 K. We also present the results of a background measurement campaign at the Spallation Neutron Source to select the area with sufficient low background to allow a successful first-time measurement of the CNNS process.

Green power programs in Canada : 2002 : Overview of Government green power policies, utility green power development programs, green power and certificate marketing initiatives, and their benefits

International Nuclear Information System (INIS)

Bramley, M.; Boustie, S.; Vadgama, J.; Wieler, C.; Pape-Salmon, A.; Holmes, R.

2003-11-01

Green power is generally defined as electricity produced from renewable sources, and whose production has low adverse impacts on the environment, human health and communities. Green power has near-zero greenhouse gas (GHG) emissions and includes sources such as wind, hydro, and solar power. Green power offers several environmental benefits, as well as the enhancement of energy security, regional development, economic diversification and the creation of skilled jobs. There are four categories of programs related to green power development in Canada: government green power policies, utility green power development programs, green power marketing initiatives, and green power certificate marketing initiatives. Most of the activities associated with these four categories in 2002 were discussed in this report. However, difficulties with quantification prevented the inclusion of some green power activities in the report, such as (1) the generation of green power not certified or identified by the generator as green power, (2) industry or residential self-generation, (3) net metering, and (4) small government programs. Each category was presented in detail. The information included in the report was based on surveys sent to each program proponent. Follow-up communications and other publicly available information was also included. New programs operating in 2003 or currently under development were listed. refs., 8 tabs

Self-formed conductive nanofilaments in (Bi, Mn)Ox for ultralow-power memory devices

KAUST Repository

Kang, Chen Fang

2015-04-01

Resistive random access memory (RRAM) is one of the most promising candidates as a next generation nonvolatile memory (NVM), owing to its superior scalability, low power consumption and high speed. From the materials science point of view, to explore optimal RRAM materials is still essential for practical application. In this work, a new material (Bi, Mn)Ox (BMO) is investigated and several key performance characteristics of Pt/BMO/Pt structured device, including switching performance, retention and endurance, are examined in details. Furthermore, it has been confirmed by high-resolution transmission electron microscopy that the underlying switching mechanism is attributed to formation and disruption of metallic conducting nanofilaments (CNFs). More importantly, the power dissipation for each CNF is as low as 3.8/20fJ for set/reset process, and a realization of cross-bar structure memory cell is demonstrated to prove the downscaling ability of proposed RRAM. These distinctive properties have important implications for understanding switching mechanisms and implementing ultralow power-dissipation RRAM based on BMO. •Self-formed conductive nanofilaments in BMO show ultralow-power memory feature.•The feature of 10nm in diameter and an average 20-30nm spacing of CNFs suggests the compatibility with the current CMOS technologies.•Power dissipation for each CNF is as low as 3.8/20fJ for set/reset process•A realization of cross-bar structure memory cell is demonstrated to prove the downscaling ability of proposed RRAM. © 2015 Elsevier Ltd.

Effect of impurities and ripple upon power regulation in self-sustained tokamaks

International Nuclear Information System (INIS)

Bromberg, L.; Cohn, D.R.

1981-01-01

Tokamak power reactors will likely operate in a self sustained heating mode where additional power losses are introduced to permit higher levels of alpha particle heating (and thus higher levels of total fusion power) at thermal equilibrium. Illustrative 0-dimensional calculations are made to assess requirements for power regulation of self sustained tokamak plasmas by the use of impurity radiation. Effects of impurities upon allowable fuel density and thermal stability are determined. Requirements are calculated for passive thermal stability control by temperature driven radial motion in the presence of ripple transport losses; it appears that stability might be attained over a relatively wide temperature range with a small amount of ripple transport loss. Requirements for power regulation by the use of ripple transport are also determined

An ultra short pulse reconstruction software applied to the GEMINI high power laser system

Energy Technology Data Exchange (ETDEWEB)

Galletti, Mario, E-mail: mario.gall22@gmail.com [INFN – LNF, Via Enrico Fermi 40, 00044 Frascati (Italy); Galimberti, Marco [Central Laser Facility, Rutherford Appleton Laboratory, Didcot (United Kingdom); Hooker, Chris [Central Laser Facility, Rutherford Appleton Laboratory, Didcot (United Kingdom); University of Oxford, Oxford (United Kingdom); Chekhlov, Oleg; Tang, Yunxin [Central Laser Facility, Rutherford Appleton Laboratory, Didcot (United Kingdom); Bisesto, Fabrizio Giuseppe [INFN – LNF, Via Enrico Fermi 40, 00044 Frascati (Italy); Curcio, Alessandro [INFN – LNF, Via Enrico Fermi 40, 00044 Frascati (Italy); Sapienza – University of Rome, P.le Aldo Moro, 2, 00185 Rome (Italy); Anania, Maria Pia [INFN – LNF, Via Enrico Fermi 40, 00044 Frascati (Italy); Giulietti, Danilo [Physics Department of the University and INFN, Pisa (Italy)

2016-09-01

The GRENOUILLE traces of Gemini pulses (15 J, 30 fs, PW, shot per 20 s) were acquired in the Gemini Target Area PetaWatt at the Central Laser Facility (CLF), Rutherford Appleton Laboratory (RAL). A comparison between the characterizations of the laser pulse parameters made using two different types of algorithms: Video Frog and GRenouille/FrOG (GROG), was made. The temporal and spectral parameters came out to be in great agreement for the two kinds of algorithms. In this experimental campaign it has been showed how GROG, the developed algorithm, works as well as VideoFrog algorithm with the PetaWatt pulse class. - Highlights: • Integration of the diagnostic tool on high power laser. • Validation of the GROG algorithm in comparison to a well-known commercial available software. • Complete characterization of the GEMINI ultra-short high power laser pulse.

Low Power Microrobotics Utilizing Biologically Inspired Energy Generation

Data.gov (United States)

National Aeronautics and Space Administration — In this Phase I study, the study team will investigate the usability of a microbial fuel cell to power a small microrover, design low-power electronics for effective...

Dual Mode Low Power Hall Thruster, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Sample and return missions desire and missions like Saturn Observer require a low power Hall thruster that can operate at high thrust to power as well as high...

A Self-Powered and Flexible Organometallic Halide Perovskite Photodetector with Very High Detectivity.

Science.gov (United States)

Leung, Siu-Fung; Ho, Kang-Ting; Kung, Po-Kai; Hsiao, Vincent K S; Alshareef, Husam N; Wang, Zhong Lin; He, Jr-Hau

2018-02-01

Flexible and self-powered photodetectors (PDs) are highly desirable for applications in image sensing, smart building, and optical communications. In this paper, a self-powered and flexible PD based on the methylammonium lead iodide (CH 3 NH 3 PBI 3 ) perovskite is demonstrated. Such a self-powered PD can operate even with irregular motion such as human finger tapping, which enables it to work without a bulky external power source. In addition, with high-quality CH 3 NH 3 PBI 3 perovskite thin film fabricated with solvent engineering, the PD exhibits an impressive detectivity of 1.22 × 10 13 Jones. In the self-powered voltage detection mode, it achieves a large responsivity of up to 79.4 V mW -1 cm -2 and a voltage response of up to ≈90%. Moreover, as the PD is made of flexible and transparent polymer films, it can operate under bending and functions at 360 ° of illumination. As a result, the self-powered, flexible, 360 ° omnidirectional perovskite PD, featuring high detectivity and responsivity along with real-world sensing capability, suggests a new direction for next-generation optical communications, sensing, and imaging applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aiding operator performance at low power feedwater control

International Nuclear Information System (INIS)

Woods, D.D.

1986-01-01

Control of the feedwater system during low power operations (approximately 2% to 30% power) is a difficult task where poor performance (excessive trips) has a high cost to utilities. This paper describes several efforts in the human factors aspects of this task that are underway to improve feedwater control. A variety of knowledge acquisition techniques have been used to understand the details of what makes feedwater control at low power difficult and what knowledge and skill distinguishes expert operators at this task from less experienced ones. The results indicate that there are multiple factors that contribute to task difficulty

Low Power Implementation of Non Power-of-Two FFTs on Coarse-Grain Reconfigurable Architectures

NARCIS (Netherlands)

Zhang, Q.; Wolkotte, P.T.; Smit, Gerardus Johannes Maria; Rivaton, Arnaud; Quevremont, Jérôme

2005-01-01

The DRM standard for digital radio broadcast in the AM band requires integrated devices for radio receivers at very low power. A System on Chip (SoC) call DiMITRI was developed based on a dual ARM9 RISC core architecture. Analyses showed that most computation power is used in the Coded Orthogonal

Capturing low-carbon power system dynamics : Interactions between intermittent renewables and power plants with CO2 capture and storage

NARCIS (Netherlands)

Brouwer, Anne-Sjoerd

2015-01-01

Low-carbon power systems are needed by the year 2050 to meet climate change mitigation targets. This dissertation investigates the operational and economic feasibility of such future low-carbon power systems by simulating the Dutch and European power systems. Particular attention is paid to the

ZnO nanoneedle/H2O solid-liquid heterojunction-based self-powered ultraviolet detector

Science.gov (United States)

2013-01-01

ZnO nanoneedle arrays were grown vertically on a fluorine-doped tin oxide-coated glass by hydrothermal method at a relatively low temperature. A self-powered photoelectrochemical cell-type UV detector was fabricated using the ZnO nanoneedles as the active photoanode and H2O as the electrolyte. This solid-liquid heterojunction offers an enlarged ZnO/water contact area and a direct pathway for electron transport simultaneously. By connecting this UV photodetector to an ammeter, the intensity of UV light can be quantified using the output short-circuit photocurrent without a power source. High photosensitivity, excellent spectral selectivity, and fast photoresponse at zero bias are observed in this UV detector. The self-powered behavior can be well explained by the formation of a space charge layer near the interface of the solid-liquid heterojunction, which results in a built-in potential and makes the solid-liquid heterojunction work in photovoltaic mode. PMID:24103153

Study on self organized criticality of China power grid blackouts

Energy Technology Data Exchange (ETDEWEB)

Zhao, Xingyong; Zhang, Xiubin; He, Bin [Department of Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)

2009-03-15

Based on the complex system theory and the concept of self organized criticality (SOC) theory, the mechanism of China power grid blackout is studied by analyzing the blackout data in the China power system from 1981 to 2002. The probability distribution functions of various measures of blackout size have a power tail. The analysis of scaled window variance and rescaled range statistics of the time series show moderate long time correlations. The blackout data seem consistent with SOC; the results obtained show that SOC dynamics may play an important role in the dynamics of power systems blackouts. It would be possible to propose novel approaches for understanding and controlling power systems blackouts. (author)

Study on self organized criticality of China power grid blackouts

Energy Technology Data Exchange (ETDEWEB)

Zhao Xingyong [Department of Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)], E-mail: zhaoxingyong@sjtu.edu.cn; Zhang Xiubin; He Bin [Department of Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)

2009-03-15

Based on the complex system theory and the concept of self organized criticality (SOC) theory, the mechanism of China power grid blackout is studied by analyzing the blackout data in the China power system from 1981 to 2002. The probability distribution functions of various measures of blackout size have a power tail. The analysis of scaled window variance and rescaled range statistics of the time series show moderate long time correlations. The blackout data seem consistent with SOC; the results obtained show that SOC dynamics may play an important role in the dynamics of power systems blackouts. It would be possible to propose novel approaches for understanding and controlling power systems blackouts.

Stirling engines for low-temperature solar-thermal-electric power generation

Science.gov (United States)

der Minassians, Artin

their self-starting potential. The start-up temperature, i.e., the heater temperature at which the system starts its operation, is derived based on the same modal analysis. Following the mathematical modeling, the design, fabrication, and test of a symmetric three-phase free-piston Stirling engine system are discussed. The system is designed to operate with moderate-temperature heat input that is consistent with solar-thermal collectors. Diaphragm pistons and nylon flexures are considered for this prototype to eliminate surface friction and provide appropriate seals. The experimental results are presented and compared with design calculations. Experimental assessments confirm the models for flow friction and gas spring hysteresis dissipation. It is revealed that gas spring hysteresis loss is an important dissipation phenomenon in low-power low-pressure Stirling engines, and should be carefully addressed during the design as it may hinder the engine operation. Further analysis shows that the gas hysteresis dissipation can be reduced drastically by increasing the number of phases in a system with a little compromise on the operating frequency and, hence, the output power. It is further shown that for an even number of phases, half of the pistons could be eliminated by utilizing a reverser. By introducing a reverser to the fabricated system, the system proves its self-starting capability in engine mode and validates the derived expressions for computing the start-up temperature.

Ultra-low noise supercontinuum source for ultra-high resolution optical coherence tomography at 1300 nm

Science.gov (United States)

Gonzalo, I. B.; Maria, M.; Engelsholm, R. D.; Feuchter, T.; Leick, L.; Moselund, P. M.; Podoleanu, A.; Bang, O.

2018-02-01

Supercontinuum (SC) sources are of great interest for many applications due to their ultra-broad optical bandwidth, good beam quality and high power spectral density [1]. In particular, the high average power over large bandwidths makes SC light sources excellent candidates for ultra-high resolution optical coherence tomography (UHR-OCT) [2-5]. However, conventional SC sources suffer from high pulse-to-pulse intensity fluctuations as a result of the noise-sensitive nonlinear effects involved in the SC generation process [6-9]. This intensity noise from the SC source can limit the performance of OCT, resulting in a reduced signal-to-noise ratio (SNR) [10-12]. Much work has been done to reduce the noise of the SC sources for instance with fiber tapers [7,8] or increasing the repetition rate of the pump laser for averaging in the spectrometer [10,12]. An alternative approach is to use all-normal dispersion (ANDi) fibers [13,14] to generate SC light from well-known coherent nonlinear processes [15-17]. In fact, reduction of SC noise using ANDi fibers compared to anomalous dispersion SC pumped by sub-picosecond pulses has been recently demonstrated [18], but a cladding mode was used to stabilize the ANDi SC. In this work, we characterize the noise performance of a femtosecond pumped ANDi based SC and a commercial SC source in an UHR-OCT system at 1300 nm. We show that the ANDi based SC presents exceptional noise properties compared to a commercial source. An improvement of 5 dB in SNR is measured in the UHR-OCT system, and the noise behavior resembles that of a superluminiscent diode. This preliminary study is a step forward towards development of an ultra-low noise SC source at 1300 nm for ultra-high resolution OCT.

FPGA Based Low Power ROM Design Using Capacitance Scaling

DEFF Research Database (Denmark)

Bansal, Meenakshi; Bansal, Neha; Saini, Rishita

2015-01-01

An ideal capacitor will not dissipate any power, but a real capacitor wil l have some power dissipation. In this work, we are going to design capacitance scaling based low power ROM design. In order to test the compatibility of this ROM design with latest i7 Processor, we are operating this ROM w...... in I/O Power, saving of 0.2% occur in Leakage Power, there will be a saving of 11.54% occur in Total Power. This design is implemented on Virtex-5 FPGA using Xilinx ISE and Verilog....

Nanostructured Bulk Thermoelectric Generator for Efficient Power Harvesting for Self-powered Sensor Networks

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yanliang [Idaho National Lab. (INL), Idaho Falls, ID (United States); Butt, Darryl [Idaho National Lab. (INL), Idaho Falls, ID (United States); Agarwal, Vivek [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-07-01

The objective of this Nuclear Energy Enabling Technology research project is to develop high-efficiency and reliable thermoelectric generators for self-powered wireless sensors nodes utilizing thermal energy from nuclear plant or fuel cycle. The power harvesting technology has crosscutting significance to address critical technology gaps in monitoring nuclear plants and fuel cycle. The outcomes of the project will lead to significant advancement in sensors and instrumentation technology, reducing cost, improving monitoring reliability and therefore enhancing safety. The self-powered wireless sensor networks could support the long-term safe and economical operation of all the reactor designs and fuel cycle concepts, as well as spent fuel storage and many other nuclear science and engineering applications. The research is based on recent breakthroughs in high-performance nanostructured bulk (nanobulk) thermoelectric materials that enable high-efficiency direct heat-to-electricity conversion over a wide temperature range. The nanobulk thermoelectric materials that the research team at Boise State University and University of Houston has developed yield up to a 50% increase in the thermoelectric figure of merit, ZT, compared with state-of-the-art bulk counterparts. This report focuses on the selection of optimal thermoelectric materials for this project. The team has performed extensive study on two thermoelectric materials systems, i.e. the half-Heusler materials, and the Bismuth-Telluride materials. The report contains our recent research results on the fabrication, characterization and thermoelectric property measurements of these two materials.

A robust low quiescent current power receiver for inductive power transmission in bio implants

Science.gov (United States)

Helalian, Hamid; Pasandi, Ghasem; Jafarabadi Ashtiani, Shahin

2017-05-01

In this paper, a robust low quiescent current complementary metal-oxide semiconductor (CMOS) power receiver for wireless power transmission is presented. This power receiver consists of three main parts including rectifier, switch capacitor DC-DC converter and low-dropout regulator (LDO) without output capacitor. The switch capacitor DC-DC converter has variable conversion ratios and synchronous controller that lets the DC-DC converter to switch among five different conversion ratios to prevent output voltage drop and LDO regulator efficiency reduction. For all ranges of output current (0-10 mA), the voltage regulator is compensated and is stable. Voltage regulator stabilisation does not need the off-chip capacitor. In addition, a novel adaptive biasing frequency compensation method for low dropout voltage regulator is proposed in this paper. This method provides essential minimum current for compensation and reduces the quiescent current more effectively. The power receiver was designed in a 180-nm industrial CMOS technology, and the voltage range of the input is from 0.8 to 2 V, while the voltage range of the output is from 1.2 to 1.75 V, with a maximum load current of 10 mA, the unregulated efficiency of 79.2%, and the regulated efficiency of 64.4%.

Low-power, miniature {sup 171}Yb ion clock using an ultra-small vacuum package

Energy Technology Data Exchange (ETDEWEB)

Jau, Y.-Y.; Schwindt, P. D. D. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Partner, H. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Center for Quantum Information and Control (CQuIC), Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Prestage, J. D.; Kellogg, J. R.; Yu, N. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

2012-12-17

We report a demonstration of a very small microwave atomic clock using the 12.6 GHz hyperfine transition of the trapped {sup 171}Yb ions inside a miniature, completely sealed-off 3 cm{sup 3} ion-trap vacuum package. In the ion clock system, all of the components are highly miniaturized with low power consumption except the 369 nm optical pumping laser still under development for miniaturization. The entire clock, including the control electronics, consumes <300 mW. The fractional frequency instability of the miniature Yb{sup +} clock reaches the 10{sup -14} range after a few days of integration.

An Ultra-Low Power Wireless Sensor Network for Bicycle Torque Performance Measurements

Science.gov (United States)

Gharghan, Sadik K.; Nordin, Rosdiadee; Ismail, Mahamod

2015-01-01

In this paper, we propose an energy-efficient transmission technique known as the sleep/wake algorithm for a bicycle torque sensor node. This paper aims to highlight the trade-off between energy efficiency and the communication range between the cyclist and coach. Two experiments were conducted. The first experiment utilised the Zigbee protocol (XBee S2), and the second experiment used the Advanced and Adaptive Network Technology (ANT) protocol based on the Nordic nRF24L01 radio transceiver chip. The current consumption of ANT was measured, simulated and compared with a torque sensor node that uses the XBee S2 protocol. In addition, an analytical model was derived to correlate the sensor node average current consumption with a crank arm cadence. The sensor node achieved 98% power savings for ANT relative to ZigBee when they were compared alone, and the power savings amounted to 30% when all components of the sensor node are considered. The achievable communication range was 65 and 50 m for ZigBee and ANT, respectively, during measurement on an outdoor cycling track (i.e., velodrome). The conclusions indicate that the ANT protocol is more suitable for use in a torque sensor node when power consumption is a crucial demand, whereas the ZigBee protocol is more convenient in ensuring data communication between cyclist and coach. PMID:26007728

An ultra-low power wireless sensor network for bicycle torque performance measurements.

Science.gov (United States)

Gharghan, Sadik K; Nordin, Rosdiadee; Ismail, Mahamod

2015-05-21

In this paper, we propose an energy-efficient transmission technique known as the sleep/wake algorithm for a bicycle torque sensor node. This paper aims to highlight the trade-off between energy efficiency and the communication range between the cyclist and coach. Two experiments were conducted. The first experiment utilised the Zigbee protocol (XBee S2), and the second experiment used the Advanced and Adaptive Network Technology (ANT) protocol based on the Nordic nRF24L01 radio transceiver chip. The current consumption of ANT was measured, simulated and compared with a torque sensor node that uses the XBee S2 protocol. In addition, an analytical model was derived to correlate the sensor node average current consumption with a crank arm cadence. The sensor node achieved 98% power savings for ANT relative to ZigBee when they were compared alone, and the power savings amounted to 30% when all components of the sensor node are considered. The achievable communication range was 65 and 50 m for ZigBee and ANT, respectively, during measurement on an outdoor cycling track (i.e., velodrome). The conclusions indicate that the ANT protocol is more suitable for use in a torque sensor node when power consumption is a crucial demand, whereas the ZigBee protocol is more convenient in ensuring data communication between cyclist and coach.

An Ultra-Low Power Wireless Sensor Network for Bicycle Torque Performance Measurements

Directory of Open Access Journals (Sweden)

Sadik K. Gharghan

2015-05-01

Full Text Available In this paper, we propose an energy-efficient transmission technique known as the sleep/wake algorithm for a bicycle torque sensor node. This paper aims to highlight the trade-off between energy efficiency and the communication range between the cyclist and coach. Two experiments were conducted. The first experiment utilised the Zigbee protocol (XBee S2, and the second experiment used the Advanced and Adaptive Network Technology (ANT protocol based on the Nordic nRF24L01 radio transceiver chip. The current consumption of ANT was measured, simulated and compared with a torque sensor node that uses the XBee S2 protocol. In addition, an analytical model was derived to correlate the sensor node average current consumption with a crank arm cadence. The sensor node achieved 98% power savings for ANT relative to ZigBee when they were compared alone, and the power savings amounted to 30% when all components of the sensor node are considered. The achievable communication range was 65 and 50 m for ZigBee and ANT, respectively, during measurement on an outdoor cycling track (i.e., velodrome. The conclusions indicate that the ANT protocol is more suitable for use in a torque sensor node when power consumption is a crucial demand, whereas the ZigBee protocol is more convenient in ensuring data communication between cyclist and coach.

Low-Power Wireless Sensor Networks Protocols, Services and Applications

CERN Document Server

Suhonen, Jukka; Kaseva, Ville; Hämäläinen, Timo D; Hännikäinen, Marko

2012-01-01

Wireless sensor network (WSN) is an ad-hoc network technology comprising even thousands of autonomic and self-organizing nodes that combine environmental sensing, data processing, and wireless networking. The applications for sensor networks range from home and industrial environments to military uses. Unlike the traditional computer networks, a WSN is application-oriented and deployed for a specific task. WSNs are data centric, which means that messages are not send to individual nodes but to geographical locations or regions based on the data content. A WSN node is typically battery powered and characterized by extremely small size and low cost. As a result, the processing power, memory, and energy resources of an individual sensor node are limited. However, the feasibility of a WSN lies on the collaboration between the nodes. A reference WSN node comprises a Micro-Controller Unit (MCU) having few Million Instructions Per Second (MIPS) processing speed, tens of kilobytes program memory, few kilobytes data m...

Green power programs in Canada : 2003 : overview of Government green power policies, utility green power implementation initiatives, green power and certificate marketing programs, and their benefits

International Nuclear Information System (INIS)

Whitmore, J.; Bramley, M.; Holmes, R.

2004-09-01

Green power is defined as electricity produced from renewable sources, and whose production has low adverse impacts on the environment, human health and communities. Green power has near-zero greenhouse gas (GHG) emissions and includes sources such as wind, hydro, and solar power. It offers several environmental benefits, as well as the enhancement of energy security, regional development, economic diversification and the creation of skilled jobs. There are four categories of programs related to green power development in Canada: government green power policies, utility green power development programs, green power marketing initiatives, and green power certificate marketing initiatives. Most of the activities in Canada associated with these four categories in 2003 were discussed in this report. However, difficulties with quantification prevented the inclusion of some green power activities such as (1) the generation of green power not certified or identified by the generator as green power, (2) industry or residential self-generation, (3) net metering, and (4) small government programs. Green power generation facilities in 2003 totaled 775 MW of capacity compared to 539 MW in 2002. Hydro capacity represented 41 per cent, followed by wind capacity at 40 per cent and wood waste at 17 per cent. Most of the green power generation facilities in 2003 were located in Alberta, followed by British Columbia, Ontario and Quebec. 230 refs., 8 tabs., 1 fig

Sensitivity change of rhodium self -powered detectors with burn-up

International Nuclear Information System (INIS)

Girgis, R.; Akimov, I.S.; Hamouda, I.

1976-01-01

The scope of the present paper is to obtain the calculation formulae to evaluate the rate of sensitivity change of the neutron self-powered detectors with burn-up. A code written in FORTRAN 4 was developed to be operational on the IBM-1130 computer. It has been established in the case of rhodium detectors that neglecting the β-particle absorption in the calculations leads to the underestimation of the detector sensitivity decrease up to 40%. The derived formulae can be used for other self-powered detectors. (author)

High-Resolution Uitra Low Power, Intergrated Aftershock and Microzonation System

Science.gov (United States)

Passmore, P.; Zimakov, L. G.

2012-12-01

Rapid Aftershock Mobilization plays an essential role in the understanding of both focal mechanism and rupture propagation caused by strong earthquakes. A quick assessment of the data provides a unique opportunity to study the dynamics of the entire earthquake process in-situ. Aftershock study also provides practical information for local authorities regarding the post earthquake activity, which is very important in order to conduct the necessary actions for public safety in the area affected by the strong earthquake. Refraction Technology, Inc. has developed a self-contained, fully integrated Aftershock System, model 160-03, providing the customer simple and quick deployment during aftershock emergency mobilization and microzonation studies. The 160-03 has no external cables or peripheral equipment for command/control and operation in the field. The 160-03 contains three major components integrated in one case: a) 24-bit resolution state-of-the art low power ADC with CPU and Lid interconnect boards; b) power source; and c) three component 2 Hz sensors (two horizontals and one vertical), and built-in ±4g accelerometer. Optionally, the 1 Hz sensors can be built-in the 160-03 system at the customer's request. The self-contained rechargeable battery pack provides power autonomy up to 7 days during data acquisition at 200 sps on continuous three weak motion and triggered three strong motion recording channels. For longer power autonomy, the 160-03 Aftershock System battery pack can be charged from an external source (solar power system). The data in the field is recorded to a built-in swappable USB flash drive. The 160-03 configuration is fixed based on a configuration file stored on the system, so no external command/control interface is required for parameter setup in the field. For visual control of the system performance in the field, the 160-03 has a built-in LED display which indicates the systems recording status as well as a hot swappable USB drive and battery

Comparison of Preamplifiers for Low-power Consumption Design

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Hyun; Kim, Han Soo; Lee, Kyu Hong; Choi, Hyo Jeong; Na, Teresa W.; Ha, Jang Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Chai, Jong Seo [Sungkyunkwan University, Suwon (Korea, Republic of)

2011-10-15

The commonly used electronic devices in radiation detector system are the preamplifier, the amplifier, ADC, and etc. to extract the signal from the detector and to process the signal. These components are composed of semiconductor devices like BJT, MOSFET, OPAMP, and etc. Performance and power consumption of these components are various according to the composition of semiconductor devices. In this study, preamplifiers, which are composed of high efficiency semiconductor devices, are compared to design low-power consumption and high performance preamplifier. To confirm the purpose, preamplifiers are designed for low-power consumption and high gain by some OPAMP (Operational Amplifier). The comparison was performed by experimental result and design simulation

Evapotranspiration Power Law in Self-Organized and Human-Managed Ecosystems

Science.gov (United States)

Zeng, R.; Cai, X.

2017-12-01

Natural systems display a profound degree of self-organization, often apparent even to the untrained eye. However, in this age of increased coupling among human and natural systems, it is unclear to what degree natural organization principles continue to govern human-managed landscapes. Here we present an emerging characteristic of terrestrial evapotranspiration (ET), one of the key components of the water cycle and energy budget, adhered to by both naturally organized and intensively managed landscapes. We find that ET variance and ET mean for ecosystems throughout the world with diverse climate conditions, vegetation structures, and land covers and land uses organize themselves according to a specific power law curve. From multi-source observations, the ET power law curve stands true through varying spatial scales, from field to region. Moreover, a phenomenon of similar ecosystems gravitating toward particular segments of the power law curve, suggests that the feature of self-optimization of ecosystems establishes the ET power law together with climatic conditions. Perhaps surprisingly, we find that landscapes persistently follow the power law curve even upon human-induced transition from rain-fed to irrigated agriculture in the American High Plains and from wetland to agricultural land in American Midwest. As such, the ET power law can be an informative tool for predicting consequences of anthropogenic disturbances to the hydrologic cycle and understanding constraints to sustainable land use.

Relations between high and low power groups: the importance of legitimacy.

Science.gov (United States)

Hornsey, Matthew J; Spears, Russell; Cremers, Iris; Hogg, Michael A

2003-02-01

Using a social identity perspective, two experiments examined the effects of power and the legitimacy of power differentials on intergroup bias. In Experiment 1, 125 math-science students were led to believe that they had high or low representation in a university decision-making body relative to social-science students and that this power position was either legitimate or illegitimate. Power did not have an independent effect on bias; rather, members of both high and low power groups showed more bias when the power hierarchy was illegitimate than when it was legitimate. This effect was replicated in Experiment 2 (N = 105). In addition, Experiment 2 showed that groups located within an unfair power hierarchy expected the superordinate power body to be more discriminatory than did those who had legitimately high or low power. The results are discussed in terms of their implications for group relations. Copyright 2003 Society for Personality and Social Psychology, Inc.

47 CFR 74.707 - Low power TV and TV translator station protection.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Low power TV and TV translator station... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.707 Low power TV and TV translator station protection. (a)(1) A low power TV or TV translator will be protected from interference from other...

Power system operation risk analysis considering charging load self-management of plug-in hybrid electric vehicles

International Nuclear Information System (INIS)

Liu, Zhe; Wang, Dan; Jia, Hongjie; Djilali, Ned

2014-01-01

Highlights: • The interactive mechanism between system and PHEVs is presented. • The charging load self-management without sacrificing user requirements is proposed. • The charging load self-management is coupled to system operation risk analysis. • The charging load self-management can reduce the extra risk brought by PHEVs. • The charging load self-management can shift charging power to the time with low risk. - Abstract: Many jurisdictions around the world are supporting the adoption of electric vehicles through incentives and the deployment of a charging infrastructure to reduce greenhouse gas emissions. Plug-in hybrid electric vehicles (PHEVs), with offer mature technology and stable performance, are expected to gain an increasingly larger share of the consumer market. The aggregated effect on power grid due to large-scale penetration of PHEVs needs to be analyzed. Nighttime-charging which typically characterizes PHEVs is helpful in filling the nocturnal load valley, but random charging of large PHEV fleets at night may result in new load peaks and valleys. Active response strategy is a potentially effective solution to mitigate the additional risks brought by the integration of PHEVs. This paper proposes a power system operation risk analysis framework in which charging load self-management is used to control system operation risk. We describe an interactive mechanism between the system and PHEVs in conjunction with a smart charging model is to simulate the time series power consumption of PHEVs. The charging load is managed with adjusting the state transition boundaries and without violating the users’ desired charging constraints. The load curtailment caused by voltage or power flow violation after outages is determined by controlling charging power. At the same time, the system risk is maintained under an acceptable level through charging load self-management. The proposed method is implemented using the Roy Billinton Test System (RBTS) and

Self-Biased Differential Rectifier with Enhanced Dynamic Range for Wireless Powering

KAUST Repository

Ouda, Mahmoud H.

2016-08-29

A self-biased, cross-coupled, differential rectifier is proposed with enhanced power-conversion efficiency over an extended range of input power. A prototype is designed for UHF 433MHz RF power-harvesting applications and is implemented using 0.18μm CMOS technology. The proposed rectifier architecture is compared to the conventional cross-coupled rectifier. It demonstrates an improvement of more than 40% in the rectifier power conversion efficiency (PCE) and an input power range extension of more than 50% relative to the conventional crosscoupled rectifier. A sensitivity of -15.2dBm (30μW) input power for 1V output voltage and a peak power-conversion efficiency of 65% are achieved for a 50kω load. © 2004-2012 IEEE.

Benefits of an ultra large and multiresolution ensemble for estimating available wind power

Science.gov (United States)

Berndt, Jonas; Hoppe, Charlotte; Elbern, Hendrik

2016-04-01

In this study we investigate the benefits of an ultra large ensemble with up to 1000 members including multiple nesting with a target horizontal resolution of 1 km. The ensemble shall be used as a basis to detect events of extreme errors in wind power forecasting. Forecast value is the wind vector at wind turbine hub height (~ 100 m) in the short range (1 to 24 hour). Current wind power forecast systems rest already on NWP ensemble models. However, only calibrated ensembles from meteorological institutions serve as input so far, with limited spatial resolution (˜10 - 80 km) and member number (˜ 50). Perturbations related to the specific merits of wind power production are yet missing. Thus, single extreme error events which are not detected by such ensemble power forecasts occur infrequently. The numerical forecast model used in this study is the Weather Research and Forecasting Model (WRF). Model uncertainties are represented by stochastic parametrization of sub-grid processes via stochastically perturbed parametrization tendencies and in conjunction via the complementary stochastic kinetic-energy backscatter scheme already provided by WRF. We perform continuous ensemble updates by comparing each ensemble member with available observations using a sequential importance resampling filter to improve the model accuracy while maintaining ensemble spread. Additionally, we use different ensemble systems from global models (ECMWF and GFS) as input and boundary conditions to capture different synoptic conditions. Critical weather situations which are connected to extreme error events are located and corresponding perturbation techniques are applied. The demanding computational effort is overcome by utilising the supercomputer JUQUEEN at the Forschungszentrum Juelich.

Modeling Creep-Fatigue-Environment Interactions in Steam Turbine Rotor Materials for Advanced Ultra-supercritical Coal Power Plants

Energy Technology Data Exchange (ETDEWEB)

Shen, Chen [General Electric Global Research, Niskayuna, NY (United States)

2014-04-01

The goal of this project is to model creep-fatigue-environment interactions in steam turbine rotor materials for advanced ultra-supercritical (A-USC) coal power Alloy 282 plants, to develop and demonstrate computational algorithms for alloy property predictions, and to determine and model key mechanisms that contribute to the damages caused by creep-fatigue-environment interactions.

Low power adder based auditory filter architecture.

Science.gov (United States)

Rahiman, P F Khaleelur; Jayanthi, V S

2014-01-01

Cochlea devices are powered up with the help of batteries and they should possess long working life to avoid replacing of devices at regular interval of years. Hence the devices with low power consumptions are required. In cochlea devices there are numerous filters, each responsible for frequency variant signals, which helps in identifying speech signals of different audible range. In this paper, multiplierless lookup table (LUT) based auditory filter is implemented. Power aware adder architectures are utilized to add the output samples of the LUT, available at every clock cycle. The design is developed and modeled using Verilog HDL, simulated using Mentor Graphics Model-Sim Simulator, and synthesized using Synopsys Design Compiler tool. The design was mapped to TSMC 65 nm technological node. The standard ASIC design methodology has been adapted to carry out the power analysis. The proposed FIR filter architecture has reduced the leakage power by 15% and increased its performance by 2.76%.

Low Power Adder Based Auditory Filter Architecture

Directory of Open Access Journals (Sweden)

P. F. Khaleelur Rahiman

2014-01-01

Full Text Available Cochlea devices are powered up with the help of batteries and they should possess long working life to avoid replacing of devices at regular interval of years. Hence the devices with low power consumptions are required. In cochlea devices there are numerous filters, each responsible for frequency variant signals, which helps in identifying speech signals of different audible range. In this paper, multiplierless lookup table (LUT based auditory filter is implemented. Power aware adder architectures are utilized to add the output samples of the LUT, available at every clock cycle. The design is developed and modeled using Verilog HDL, simulated using Mentor Graphics Model-Sim Simulator, and synthesized using Synopsys Design Compiler tool. The design was mapped to TSMC 65 nm technological node. The standard ASIC design methodology has been adapted to carry out the power analysis. The proposed FIR filter architecture has reduced the leakage power by 15% and increased its performance by 2.76%.

Field emission device driven by self-powered contact-electrification: Simulation and experimental analysis

Science.gov (United States)

Chen, Xiangyu; Jiang, Tao; Sun, Zhuo; Ou-Yang, Wei

2015-09-01

A self-powered field emission device (FED) driven by a single-electrode tribo-electric nanogenerator (TENG) is demonstrated. The mechanical motion works as both a power supply to drive the FED and a control unit to regulate the amount of emitted electrons. By using the Fowler-Nordheim equation and Kirchhoff laws, a theoretical model of this self-powered FED is proposed, and accordingly the real-time output characteristics of the device are systematically investigated. It is found that the motion distance of the TENG controls switch-on of the FED and determines the charge amount for emission, while the motion velocity regulates the amplitude of emission current. The minimum contact area for the TENG to generate field emission is about 9 cm2, which can be improved by optimizing FED structure and the tribo-materials of TENG. The demonstrated concept of this self-powered FED as well as the proposed physical analysis can serve as guidance for further applications of FED in such fields of self-powered electronics and soft electronics.

Field emission device driven by self-powered contact-electrification: Simulation and experimental analysis

Energy Technology Data Exchange (ETDEWEB)

Chen, Xiangyu, E-mail: chenxiangyu@binn.cas.cn, E-mail: ouyangwei@phy.ecnu.edu.cn; Jiang, Tao [Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083 (China); Sun, Zhuo; Ou-Yang, Wei, E-mail: chenxiangyu@binn.cas.cn, E-mail: ouyangwei@phy.ecnu.edu.cn [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062 (China)

2015-09-14

A self-powered field emission device (FED) driven by a single-electrode tribo-electric nanogenerator (TENG) is demonstrated. The mechanical motion works as both a power supply to drive the FED and a control unit to regulate the amount of emitted electrons. By using the Fowler-Nordheim equation and Kirchhoff laws, a theoretical model of this self-powered FED is proposed, and accordingly the real-time output characteristics of the device are systematically investigated. It is found that the motion distance of the TENG controls switch-on of the FED and determines the charge amount for emission, while the motion velocity regulates the amplitude of emission current. The minimum contact area for the TENG to generate field emission is about 9 cm{sup 2}, which can be improved by optimizing FED structure and the tribo-materials of TENG. The demonstrated concept of this self-powered FED as well as the proposed physical analysis can serve as guidance for further applications of FED in such fields of self-powered electronics and soft electronics.

Field emission device driven by self-powered contact-electrification: Simulation and experimental analysis

International Nuclear Information System (INIS)

Chen, Xiangyu; Jiang, Tao; Sun, Zhuo; Ou-Yang, Wei

2015-01-01

A self-powered field emission device (FED) driven by a single-electrode tribo-electric nanogenerator (TENG) is demonstrated. The mechanical motion works as both a power supply to drive the FED and a control unit to regulate the amount of emitted electrons. By using the Fowler-Nordheim equation and Kirchhoff laws, a theoretical model of this self-powered FED is proposed, and accordingly the real-time output characteristics of the device are systematically investigated. It is found that the motion distance of the TENG controls switch-on of the FED and determines the charge amount for emission, while the motion velocity regulates the amplitude of emission current. The minimum contact area for the TENG to generate field emission is about 9 cm 2 , which can be improved by optimizing FED structure and the tribo-materials of TENG. The demonstrated concept of this self-powered FED as well as the proposed physical analysis can serve as guidance for further applications of FED in such fields of self-powered electronics and soft electronics

An Active Capacitor with Self-Power and Internal Feedback Control Signals

DEFF Research Database (Denmark)

Wang, Haoran; Wang, Huai

2017-01-01

This paper proposes a concept of two-terminal active capacitor implemented by power semiconductor switches and passive elements. The active capacitor has the same level of convenience as a passive one with two power terminals only. A control strategy that does not require any external feedback...... signal is proposed and a self-power scheme for gate drivers and the controller is applied to achieve the two-terminal active capacitor. The concept, control method, self-power scheme, efficiency, and impedance characteristics of the active capacitor are presented. A case study of the proposed active...... capacitor for a capacitive DC-link application is discussed. The results reveal a significantly lower overall energy storage of passive elements and a reduced cost to fulfill a specific reliability target, compared to a passive capacitor solution. Proof-of-concept experimental results are given to verify...

A Self-Powered and Flexible Organometallic Halide Perovskite Photodetector with Very High Detectivity

KAUST Repository

Leung, Siu; Ho, Kang-Ting; Kung, Po-Kai; Hsiao, Vincent K. S.; Alshareef, Husam N.; Wang, Zhong Lin; He, Jr-Hau

2018-01-01

Flexible and self-powered photodetectors (PDs) are highly desirable for applications in image sensing, smart building, and optical communications. In this paper, a self-powered and flexible PD based on the methylammonium lead iodide (CH3 NH3 PBI3

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

Science.gov (United States)

Shen, Fei-Ran; Kuang, Hao; Hu, Feng-Xia; Wu, Hui; Huang, Qing-Zhen; Liang, Fei-Xiang; Qiao, Kai-Ming; Li, Jia; Wang, Jing; Liu, Yao; Zhang, Lei; He, Min; Zhang, Ying; Zuo, Wen-Liang; Sun, Ji-Rong; Shen, Bao-Gen

2017-10-01

Materials with zero thermal expansion (ZTE) or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE) materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn-Co-Ge-In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10-6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

Directory of Open Access Journals (Sweden)

Fei-Ran Shen

2017-10-01

Full Text Available Materials with zero thermal expansion (ZTE or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn–Co–Ge–In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10−6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

High to ultra-high power electrical energy storage.

Science.gov (United States)

Sherrill, Stefanie A; Banerjee, Parag; Rubloff, Gary W; Lee, Sang Bok

2011-12-14

High power electrical energy storage systems are becoming critical devices for advanced energy storage technology. This is true in part due to their high rate capabilities and moderate energy densities which allow them to capture power efficiently from evanescent, renewable energy sources. High power systems include both electrochemical capacitors and electrostatic capacitors. These devices have fast charging and discharging rates, supplying energy within seconds or less. Recent research has focused on increasing power and energy density of the devices using advanced materials and novel architectural design. An increase in understanding of structure-property relationships in nanomaterials and interfaces and the ability to control nanostructures precisely has led to an immense improvement in the performance characteristics of these devices. In this review, we discuss the recent advances for both electrochemical and electrostatic capacitors as high power electrical energy storage systems, and propose directions and challenges for the future. We asses the opportunities in nanostructure-based high power electrical energy storage devices and include electrochemical and electrostatic capacitors for their potential to open the door to a new regime of power energy.

Comparative analysis of the application of different Low Power Wide Area Network technologies in power grid

Science.gov (United States)

Wang, Hao; Sui, Hong; Liao, Xing; Li, Junhao

2018-03-01

Low Power Wide Area Network (LPWAN) technologies developed rapidly in recent years, but the application principle of different LPWAN technologies in power grid is still not clear. This paper gives a comparative analysis of two mainstream LPWAN technologies including NB-IoT and LoRa, and gives an application suggestion of these two LPWAN technologies, which can guide the planning and construction of LPWAN in power grid.

An Ultra-Low-Power RFID/NFC Frontend IC Using 0.18 μm CMOS Technology for Passive Tag Applications

Directory of Open Access Journals (Sweden)

Mayukh Bhattacharyya

2018-05-01

Full Text Available Battery-less passive sensor tags based on RFID or NFC technology have achieved much popularity in recent times. Passive tags are widely used for various applications like inventory control or in biotelemetry. In this paper, we present a new RFID/NFC frontend IC (integrated circuit for 13.56 MHz passive tag applications. The design of the frontend IC is compatible with the standard ISO 15693/NFC 5. The paper discusses the analog design part in details with a brief overview of the digital interface and some of the critical measured parameters. A novel approach is adopted for the demodulator design, to demodulate the 10% ASK (amplitude shift keying signal. The demodulator circuit consists of a comparator designed with a preset offset voltage. The comparator circuit design is discussed in detail. The power consumption of the bandgap reference circuit is used as the load for the envelope detection of the ASK modulated signal. The sub-threshold operation and low-supply-voltage are used extensively in the analog design—to keep the power consumption low. The IC was fabricated using 0.18 μ m CMOS technology in a die area of 1.5 mm × 1.5 mm and an effective area of 0.7 m m 2 . The minimum supply voltage desired is 1.2 V, for which the total power consumption is 107 μ W. The analog part of the design consumes only 36 μ W, which is low in comparison to other contemporary passive tags ICs. Eventually, a passive tag is developed using the frontend IC, a microcontroller, a temperature and a pressure sensor. A smart NFC device is used to readout the sensor data from the tag employing an Android-based application software. The measurement results demonstrate the full passive operational capability. The IC is suitable for low-power and low-cost industrial or biomedical battery-less sensor applications. A figure-of-merit (FOM is proposed in this paper which is taken as a reference for comparison with other related state-of-the-art researches.

An Ultra-Low-Power RFID/NFC Frontend IC Using 0.18 μm CMOS Technology for Passive Tag Applications.

Science.gov (United States)

Bhattacharyya, Mayukh; Gruenwald, Waldemar; Jansen, Dirk; Reindl, Leonhard; Aghassi-Hagmann, Jasmin

2018-05-07

Battery-less passive sensor tags based on RFID or NFC technology have achieved much popularity in recent times. Passive tags are widely used for various applications like inventory control or in biotelemetry. In this paper, we present a new RFID/NFC frontend IC (integrated circuit) for 13.56 MHz passive tag applications. The design of the frontend IC is compatible with the standard ISO 15693/NFC 5. The paper discusses the analog design part in details with a brief overview of the digital interface and some of the critical measured parameters. A novel approach is adopted for the demodulator design, to demodulate the 10% ASK (amplitude shift keying) signal. The demodulator circuit consists of a comparator designed with a preset offset voltage. The comparator circuit design is discussed in detail. The power consumption of the bandgap reference circuit is used as the load for the envelope detection of the ASK modulated signal. The sub-threshold operation and low-supply-voltage are used extensively in the analog design—to keep the power consumption low. The IC was fabricated using 0.18 μ m CMOS technology in a die area of 1.5 mm × 1.5 mm and an effective area of 0.7 m m 2 . The minimum supply voltage desired is 1.2 V, for which the total power consumption is 107 μ W. The analog part of the design consumes only 36 μ W, which is low in comparison to other contemporary passive tags ICs. Eventually, a passive tag is developed using the frontend IC, a microcontroller, a temperature and a pressure sensor. A smart NFC device is used to readout the sensor data from the tag employing an Android-based application software. The measurement results demonstrate the full passive operational capability. The IC is suitable for low-power and low-cost industrial or biomedical battery-less sensor applications. A figure-of-merit (FOM) is proposed in this paper which is taken as a reference for comparison with other related state-of-the-art researches.

Adoption of nitrogen power conversion system for small scale ultra-long cycle fast reactor eliminating intermediate sodium loop

International Nuclear Information System (INIS)

Seo, Seok Bin; Seo, Han; Bang, In Cheol

2016-01-01

Highlights: • N 2 power conversion system for both safety and thermal performance aspects. • Sensitivity studies of several controlled parameters on N 2 power conversion system. • The elimination of the intermediate loop increased the cycle thermal efficiency. • The elimination of the intermediate loop expects economic advantages. - Abstract: As one of SFRs, the ultra-long cycle fast reactor with a power rating of 100 MW e (UCFR-100) was introduced for a 60-year operation. As an alternative to the traditional steam Rankine cycle for the power conversion system, gas based Brayton cycle has been considered for UCFR-100. Among Supercritical CO 2 (S-CO 2 ), Helium (He), Nitrogen (N 2 ) as candidates for the power conversion system for UCFR-100, an N 2 power conversion system was chosen considering both safety and thermal performance aspects. The elimination of the intermediate sodium loop could be achieved due to the safety and stable characteristics of nitrogen working fluid. In this paper, sensitivity studies with respect to several controlled parameters on N 2 power conversion system were performed to optimize the system. Furthermore, the elimination of the intermediate loop was evaluated with respect to its impact on the thermodynamic performance and other aspects.

Nanoelectromechanical Switches for Low-Power Digital Computing

Directory of Open Access Journals (Sweden)

Alexis Peschot

2015-08-01

Full Text Available The need for more energy-efficient solid-state switches beyond complementary metal-oxide-semiconductor (CMOS transistors has become a major concern as the power consumption of electronic integrated circuits (ICs steadily increases with technology scaling. Nano-Electro-Mechanical (NEM relays control current flow by nanometer-scale motion to make or break physical contact between electrodes, and offer advantages over transistors for low-power digital logic applications: virtually zero leakage current for negligible static power consumption; the ability to operate with very small voltage signals for low dynamic power consumption; and robustness against harsh environments such as extreme temperatures. Therefore, NEM logic switches (relays have been investigated by several research groups during the past decade. Circuit simulations calibrated to experimental data indicate that scaled relay technology can overcome the energy-efficiency limit of CMOS technology. This paper reviews recent progress toward this goal, providing an overview of the different relay designs and experimental results achieved by various research groups, as well as of relay-based IC design principles. Remaining challenges for realizing the promise of nano-mechanical computing, and ongoing efforts to address these, are discussed.

Fiber-distributed Ultra-wideband noise radar with steerable power spectrum and colorless base station.

Science.gov (United States)

Zheng, Jianyu; Wang, Hui; Fu, Jianbin; Wei, Li; Pan, Shilong; Wang, Lixian; Liu, Jianguo; Zhu, Ninghua

2014-03-10

A fiber-distributed Ultra-wideband (UWB) noise radar was achieved, which consists of a chaotic UWB noise source based on optoelectronic oscillator (OEO), a fiber-distributed transmission link, a colorless base station (BS), and a cross-correlation processing module. Due to a polarization modulation based microwave photonic filter and an electrical UWB pass-band filter embedded in the feedback loop of the OEO, the power spectrum of chaotic UWB signal could be shaped and notch-filtered to avoid the spectrum-overlay-induced interference to the narrow band signals. Meanwhile, the wavelength-reusing could be implemented in the BS by means of the distributed polarization modulation-to-intensity modulation conversion. The experimental comparison for range finding was carried out as the chaotic UWB signal was notch-filtered at 5.2 GHz and 7.8 GHz or not. Measured results indicate that space resolution with cm-level could be realized after 3-km fiber transmission thanks to the excellent self-correlation property of the UWB noise signal provided by the OEO. The performance deterioration of the radar raised by the energy loss of the notch-filtered noise signal was negligible.

A low-power wave union TDC implemented in FPGA

International Nuclear Information System (INIS)

Wu, Jinyuan; Shi, Yanchen; Zhu, Douglas

2011-01-01

A low-power time-to-digital convertor (TDC) for an application inside a vacuum has been implemented based on the Wave Union TDC scheme in a low-cost field programmable gate array (FPGA) device. Bench top tests have shown that a time measurement resolution better than 30 ps (standard deviation of time differences between two channels) is achieved. Special firmware design practices are taken to reduce power consumption. The measurements indicate that with 32 channels fitting in the FPGA device, the power consumption on the FPGA core voltage is approximately 9.3 mW/channel and the total power consumption including both core and I/O banks is less than 27 mW/channel.

Challenges for future space power systems

International Nuclear Information System (INIS)

Brandhorst, H.W. Jr.

1989-01-01

Forecasts of space power needs are presented. The needs fall into three broad categories: survival, self-sufficiency, and industrialization. The cost of delivering payloads to orbital locations and from Low Earth Orbit (LEO) to Mars are determined. Future launch cost reductions are predicted. From these projections the performances necessary for future solar and nuclear space power options are identified. The availability of plentiful cost effective electric power and of low cost access to space are identified as crucial factors in the future extension of human presence in space

A new self-powered flux detector

International Nuclear Information System (INIS)

Allan, C.J.

1979-11-01

It has been found that an Inconel-Inconel coaxial cable can be used as a fast-responding, neutron, self-powered flux detector if the core wire is sufficiently large. Test results obtained with such a detector, having a core wire approximately 1.5 mm in diameter, are presented. Other materials suitable for use as an emitter material, in such a relatively large diameter detector, also are included. (auth)

Optimized Envelope Tracking Power Supply for Tetra2 Base Station RF Power Amplifier

DEFF Research Database (Denmark)

Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

2008-01-01

An ultra-fast tracking power supply (UFTPS) for envelope tracking in a 50kHz 64-QAM Tetra2 base station power amplification system is demonstrated. A simple method for optimizing the step response of the PID+PD sliding-mode control system is presented and demonstrated, along with a PLL-based scheme...... application. Also demonstrated is the effect of non-zero UFTPS output impedance on envelope tracking performance. At 13W average (156W peak) RF output, a reduction of DC input power consumption from 93W (14% efficiency) to 54W (24% efficiency) is obtained by moving from a fixed RF power amplifier supply...

Laser power meters as an X-ray power diagnostic for LCLS-II.

Science.gov (United States)

Heimann, Philip; Moeller, Stefan; Carbajo, Sergio; Song, Sanghoon; Dakovski, Georgi; Nordlund, Dennis; Fritz, David

2018-01-01

For the LCLS-II X-ray instruments, laser power meters are being developed as compact X-ray power diagnostics to operate at soft and tender X-ray photon energies. These diagnostics can be installed at various locations along an X-ray free-electron laser (FEL) beamline in order to monitor the transmission of X-ray optics along the beam path. In addition, the power meters will be used to determine the absolute X-ray power at the endstations. Here, thermopile power meters, which measure average power, and have been chosen primarily for their compatibility with the high repetition rates at LCLS-II, are evaluated. A number of characteristics in the soft X-ray range are presented including linearity, calibrations conducted with a photodiode and a gas monitor detector as well as ultra-high-vacuum compatibility tests using residual gas analysis. The application of these power meters for LCLS-II and other X-ray FEL sources is discussed.

47 CFR 74.785 - Low power TV digital data service pilot project.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Low power TV digital data service pilot project... Power TV, TV Translator, and TV Booster Stations § 74.785 Low power TV digital data service pilot project. Low power TV stations authorized pursuant to the LPTV Digital Data Services Act (Public Law 106...

Photovoltaic-Pyroelectric Coupled Effect Induced Electricity for Self-Powered Photodetector System.

Science.gov (United States)

Ma, Nan; Zhang, Kewei; Yang, Ya

2017-12-01

Ferroelectric materials have demonstrated novel photovoltaic effect to scavenge solar energy. However, most of the ferroelectric materials with wide bandgaps (2.7-4 eV) suffer from low power conversion efficiency of less than 0.5% due to absorbing only 8-20% of solar spectrum. Instead of harvesting solar energy, these ferroelectric materials can be well suited for photodetector applications, especially for sensing near-UV irradiations. Here, a ferroelectric BaTiO 3 film-based photodetector is demonstrated that can be operated without using any external power source and a fast sensing of 405 nm light illumination is enabled. As compared with photovoltaic effect, both the responsivity and the specific detectivity of the photodetector can be dramatically enhanced by larger than 260% due to the light-induced photovoltaic-pyroelectric coupled effect. A self-powered photodetector array system can be utilized to achieve spatially resolved light intensity detection by recording the output voltage signals as a mapping figure. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quality of the current low power and shutdown PSA practice

International Nuclear Information System (INIS)

Jang, Seung Cheol; Park, Jin Hee; Lim, Ho Gon; Kim, Tae Woon

2004-01-01

A probabilistic safety assessment (PSA) for the low-power and shutdown (LPSD) modes in a Korea standard nuclear power plant (KSNP) has been performed for the purpose of estimating the LPSD risk and identifying the vulnerabilities of LPSD operations. Both the operational experience and PSA results indicate that the risks from LPSD operations could be comparable with those from power operations. However, the application of the LPSD risk insights to risk-informed decision making has been slow to be adopted in practice. It is largely due to the question of whether the current LPSD PSA practice is appropriate for application to risk-informed decision making or not. Such a question has to do with the quality of the current LPSD PSA practice. In this paper, we have performed self-assessment of the KSNP LPSD PSA quality based on the ANS Standard (draft as of 13 Sep. 2002). The aims of the work are to find the LPSD PSA technical areas insufficient for application to risk-informed decision making and to efficiently allocate the limited research resources to improve the LPSD PSA model quality. Many useful findings regarding the current LPSD PSA quality are presented in this paper

UAV Low Altitude Photogrammetry for Power Line Inspection

Directory of Open Access Journals (Sweden)

Yong Zhang

2017-01-01

Full Text Available When the distance between an obstacle and a power line is less than the discharge distance, a discharge arc can be generated, resulting in the interruption of power supplies. Therefore, regular safety inspections are necessary to ensure the safe operation of power grids. Tall vegetation and buildings are the key factors threatening the safe operation of extra high voltage transmission lines within a power line corridor. Manual or laser intensity direction and ranging (LiDAR based inspections are time consuming and expensive. To make safety inspections more efficient and flexible, a low-altitude unmanned aerial vehicle (UAV remote-sensing platform, equipped with an optical digital camera, was used to inspect power line corridors. We propose a semi-patch matching algorithm based on epipolar constraints, using both the correlation coefficient (CC and the shape of its curve to extract three dimensional (3D point clouds for a power line corridor. We use a stereo image pair from inter-strip to improve power line measurement accuracy by transforming the power line direction to an approximately perpendicular to epipolar line. The distance between the power lines and the 3D point cloud is taken as a criterion for locating obstacles within the power line corridor automatically. Experimental results show that our proposed method is a reliable, cost effective, and applicable way for practical power line inspection and can locate obstacles within the power line corridor with accuracy better than ±0.5 m.

Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency

Science.gov (United States)

Ferin, G.; Bantignies, C.; Le Khanh, H.; Flesch, E.; Nguyen-Dinh, A.

2015-12-01

Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations.

Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency

International Nuclear Information System (INIS)

Ferin, G; Bantignies, C; Khanh, H Le; Flesch, E; Nguyen-Dinh, A

2015-01-01

Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations. (paper)

Recent advances in self-powered flux detector development for CANDU reactors

International Nuclear Information System (INIS)

Allan, C.J.; Drewell, N.H.; Hall, D.S.

1983-01-01

The characteristics of self-powered flux detectors used in CANDU reactors are reviewed. Detectors with emitters of vanadium, platinum, platinum-clad Inconel and Inconel are used. Data on dynamic response, relative neutron and gamma-ray sensitivities, and burnout, obtained both from experiments and from the Monte Carlo code ICARES, are presented. Since the response of a detector depends on the relative magnitudes of the various current-producing mechanisms, the operating principles of self-powered detectors are briefly reviewed. Current research programmes are discussed. These include modifying the design of the platinum-clad Inconel detector in order to match its dynamic response to that of the fuel power and developing a prompt-responding flux-mapping detector. (author)

Low energy, high power injection in JT-60 NBI

International Nuclear Information System (INIS)

Mizuno, Makoto; Dairaku, Masayuki; Horiike, Hiroshi

1988-05-01

JT-60 neutral beam injector (JT-60 NBI) is designed to inject 20 MW neutral hydrogen beam at energies of 70 ∼ 100 keV and the injection power decreases significantly at low energies (∼40 keV). For the extention of operation region aiming at the low density plasma heating and achieving H-mode by plasma periphery heating, increment of the injection power at low beam energies was required. The single-stage acceleration system was investigated in advance at the Prototype Injector Unit. From this result, the total injection power of 17 MW at 40 keV, 48 A per source was expected at the JT-60 NBI. This system was adopted in the JT-60 NBI from June, 1987 to July, 1987 and 17.6 MW neutral beam injection power was achieved. In the NB heating experiment, the H-mode transition phenomena was observed in JT-60 plasma. (author)

Development of Micro-sized Microbial Fuel Cells as Ultra-Low Power Generators Using Nano-engineered Materials and Sustainable Designs

KAUST Repository

Mink, Justine E.

2013-12-01

Many of the most pressing global challenges today and in the future center around the scarcity of sustainable energy and water sources. The innovative microbial fuel cell (MFC) technology addresses both as it utilizes bacteria to convert wastewaters into electricity. Advancing this technology requires a better understanding of the optimal materials, designs and conditions involved. The micro-sized MFC was recently developed to serve this need by providing a rapid testing device requiring only a fraction of the materials. Further, development of micro-liter scale MFCs has expanded into potential applications such as remote and self-sustained power sources as well as on-chip energy generators. By using microfabrication, the fabrication and assembly of microsized MFCs is potentially inexpensive and mass produced. The objective of the work within this dissertation was to explore and optimize the micro-sized MFC to maximize power and current generation towards the goal of a usable and application-oriented device. Micro-sized MFCs were examined and developed using four parameters/themes considered most important in producing a high power generating, yet usable device: Anode- The use of nano-engineered carbon nanomaterials, carbon nanotubes and graphene, as anode as well as testing semiconductor industry standard anode contact area materials for enhanced current production. 5 Cathode- The introduction of a membrane-less air cathode to eliminate the need for continuous chemical refills and making the entire device mobile. Reactor design- The testing of four different reactor designs (1-75 μLs) with various features intended to increase sustainability, cost-effectiveness, and usability of the microsized MFC. Fuels- The utilization of real-world fuels, such as industrial wastewaters and saliva, to power micro-sized MFCs. The micro-sized MFC can be tailored to fit a variety of applications by varying these parameters. The device with the highest power production here was

Authenticated Encryption for Low-Power Reconfigurable Wireless Devices

DEFF Research Database (Denmark)

Khajuria, Samant; Andersen, Birger

2013-01-01

this enabling technology, these radios have to propose cryptographic services such as con- fidentiality, integrity and authentication. Therefore, integration of security services to these low-power devices is very challenging and crucial as they have limited resources and computational capabilities....... In this paper, we present a crypto solution for reconfigurable devices. The solution is a single pass Authenticated Encryption (AE) scheme that is designed for protecting both message confidentiality and its authenticity. This makes AE very attractive for low-cost low-power hardware implementation. For test...

An ultra-low-power pulse oximeter implemented with an energy-efficient transimpedance amplifier.

Science.gov (United States)

Tavakoli, M; Turicchia, L; Sarpeshkar, R

2010-02-01