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Article
Publication date: 1 December 1942

THE Funk Gerat 10 equipment is the latest standardized type, and is installed in all the later bombers and reconnaissance machines of the Luftwaffe.

Abstract

THE Funk Gerat 10 equipment is the latest standardized type, and is installed in all the later bombers and reconnaissance machines of the Luftwaffe.

Details

Aircraft Engineering and Aerospace Technology, vol. 14 no. 12
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 31 July 2009

Yusuf Onur Koçberber, Yusuf Osmanlıoğlu and Oğuz Ergin

The purpose of this paper is to reduce parity generation latency if the input value is narrow.

Abstract

Purpose

The purpose of this paper is to reduce parity generation latency if the input value is narrow.

Design/methodology/approach

Soft errors caused by cosmic particles and radiation emitted by the packaging are important problems in contemporary microprocessors. Parity bits are used to detect single bit errors that occur in the storage components. In order to implement parity logic, multiple levels of XOR gates are used and these XOR trees are known to have high delay. Many produced and consumed values inside a processor hold consecutive zeros and ones in their upper order bits. These values can be represented with less number of bits and hence are termed narrow. In this paper, a parity generator circuit design is proposed that is capable of generating parity if the input value is narrow. It is shown that the parity can be generated faster than a regular XOR tree implementation using this design for the values that can be represented using fewer bits.

Findings

The proposed technique reduces the parity generation latency of 64‐bit values by 50 percent for eight‐bit narrow values. Considering the fact that around 70 percent of the immediate values written to the immediate field of the issue queue and around 40 percent of the value written to the integer register file can be expressed with only eight bits, the coverage of the proposed scheme is quite high.

Originality/value

This paper shows the simulation results of fast parity generator circuit if the input value is narrow.

Details

Microelectronics International, vol. 26 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 3 January 2017

Vesna Rubežić, Igor Djurović and Ervin Sejdić

The purpose of this paper is to propose a new algorithm for detection of chaos in oscillatory circuits. The algorithm is based on the wavelet transform.

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Abstract

Purpose

The purpose of this paper is to propose a new algorithm for detection of chaos in oscillatory circuits. The algorithm is based on the wavelet transform.

Design/methodology/approach

The proposed detection is developed by using a specific measure obtained by averaging wavelet coefficients. This measure exhibits various values for chaotic and periodic states.

Findings

The proposed algorithm is applied to signals from autonomous systems such as the Chua’s oscillatory circuit, the Lorenz chaotic system and non-autonomous systems such as the Duffing oscillator. In addition, the detection is applied to sequences obtained from the logistic map. The results are compared to those obtained with a detrended fluctuation analysis and a time-frequency signal analysis based on detectors of chaotic states.

Originality/value

In this paper, a new algorithm is proposed for the detection of chaos from a single time series. The proposed technique is robust to the noise influence, having smaller calculation complexity with respect to the state-of-the-art techniques. It is suitable for real-time detection with delay that is about half of the window width.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 7 January 2020

Mehran Hazer Sahlabadi, Abdolali Abdipour and Abbas Mohammadi

The purpose of this paper is to study the effect of diode power detector modelling on six-port communication receiver performance.

Abstract

Purpose

The purpose of this paper is to study the effect of diode power detector modelling on six-port communication receiver performance.

Design/methodology/approach

Based on proposed and conventional squared diode model, six-port receiver’s demodulation and its error vector magnitude (EVM) performance due to hardware impairments are studied. Through considering both the models, the accuracy of proposed power detector model is compared to the squared model, and then both results are validated with envelope simulation (ENV) in advanced design system (ADS).

Findings

Comparing the numerical results with envelope simulation results proved that the proposed model is much more accurate than the conventional squared model for a wide range of input power levels.

Originality/value

Studying the receiver’s performance numerically, by considering the new proposed analytical approach for diode power detectors which is more accurate than the conventional squared model.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 39 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 9 September 2013

Hanshan Li and Zhiyong Lei

The purpose of this paper is to improve photoelectric detection target (PDT) optical detection performance and detection view, by analyzing its influence factors and…

Abstract

Purpose

The purpose of this paper is to improve photoelectric detection target (PDT) optical detection performance and detection view, by analyzing its influence factors and putting forward a new method to design its optical detection system.

Design/methodology/approach

Using rectangle linked photoelectric detector, with low noise and high response, to design optical detection system and gain faint projectile image information; bringing forward a deviating focusing technique to eliminate detection blind area of photoelectric detector; and designing adjustable slit diaphragm to weaken background light influence.

Findings

The results of experimentation in shooting range show that the new PDT has improved detection sensitivity and performance.

Originality/value

The paper presents a new design method in photoelectric detection target (PDT) optical detection system, which can provide a new method to design fire across measurement system and gain accurate projectile's coordinates data in the shooting range.

Article
Publication date: 12 August 2021

Guoda Wang, Ping Li, Yumei Wen and Zhichun Luo

Existing control circuits for piezoelectric energy harvesting (PEH) suffers from long startup time or high power consumption. This paper aims to design an ultra-low power…

Abstract

Purpose

Existing control circuits for piezoelectric energy harvesting (PEH) suffers from long startup time or high power consumption. This paper aims to design an ultra-low power control circuit that can harvest weak ambient vibrational energy on the order of several microwatts to power heavy loads such as wireless sensors.

Design/methodology/approach

A self-powered control circuit is proposed, functioning for very brief periods at the maximum power point, resulting in a low duty cycle. The circuit can start to function at low input power thresholds and can promptly achieve optimal operating conditions when cold-starting. The circuit is designed to be able to operate without stable DC power supply and powered by the piezoelectric transducers.

Findings

When using the series-synchronized switch harvesting on inductor circuit with a large 1 mF energy storage capacitor, the proposed circuit can perform 322% better than the standard energy harvesting circuit in terms of energy harvested. This control circuit can also achieve an ultra-low consumption of 0.3 µW, as well as capable of cold-starting with input power as low as 5.78 µW.

Originality/value

The intermittent control strategy proposed in this paper can drastically reduce power consumption of the control circuit. Without dedicated cold-start modules and DC auxiliary supply, the circuit can achieve optimal efficiency within one input cycle, if the input signal is larger than voltage threshold. The proposed control strategy is especially favorable for harvesting energy from natural vibrations and can be a promising solution for other PEH circuits as well.

Details

Circuit World, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 July 1954

EXISTING fire detectors are mainly or the unit type, which is placed at a number of points in the fire zone. Fire will thus be detected when the temperature of one of the…

Abstract

EXISTING fire detectors are mainly or the unit type, which is placed at a number of points in the fire zone. Fire will thus be detected when the temperature of one of the detectors is raised to its operating value by the flame, and if the fire happens to arise where there is no detector it will not be indicated until it has spread some distance. The unit detector can be very sensitive, but the operating temperature must not be set so low that it may be set off by ambient conditions short of fire, which may not be readily predictable. The unit detector also requires electric wiring, which must be in the fire zone, and an adequate number of detectors, with the necessary wiring, may well be heavy, apart from the difficulty of providing cables which will stand up to the fire zone conditions.

Details

Aircraft Engineering and Aerospace Technology, vol. 26 no. 7
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 January 1990

Bennett J. Price

Fire protection has several components: prevention, containment, detection, and suppression. While building codes and inspectors generally do not require special…

Abstract

Fire protection has several components: prevention, containment, detection, and suppression. While building codes and inspectors generally do not require special construction techniques or fire protection systems for computer rooms, economic and service factors may dictate that special protection be given such facilities. This article discusses emergency planning, the various types of fire detection and suppression systems, and future options, with particular attention given to halon and possiblehalon‐replacements.

Details

Library Hi Tech, vol. 8 no. 1
Type: Research Article
ISSN: 0737-8831

Article
Publication date: 1 January 1950

R.H. Selby‐Hele

SO much good work has been done by the Airworthiness Authorities who, as a group, are the principal signatories to ICAO, that in certain transport category aircraft of…

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Abstract

SO much good work has been done by the Airworthiness Authorities who, as a group, are the principal signatories to ICAO, that in certain transport category aircraft of recent vintage the chances are now reasonably remote of a fire occurring in flight, while the prospects of extinguishing it are roughly in inverse ratio to the chance of it occurring. Unfortunately, owing to the fact that relevant regulations are not always retroactive and in agreement, there are still far too few of these low fire‐risk aircraft.

Details

Aircraft Engineering and Aerospace Technology, vol. 22 no. 1
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 3 May 2013

Habib Adrang and Seyed Saleh Ghoreishi

Bang‐bang clock and data recovery (BBCDR) circuits are hard nonlinear systems due to the nonlinearity introduced by the binary phase detector (BPD). The specification of…

Abstract

Purpose

Bang‐bang clock and data recovery (BBCDR) circuits are hard nonlinear systems due to the nonlinearity introduced by the binary phase detector (BPD). The specification of the CDR frequency response is determined by jitter tolerance and jitter transfer. In this paper, jitter transfer and jitter tolerance of the BBCDR are characterized.

Design/methodology/approach

The presented method is enough to be used for designing the BBCDR loop parameters.

Findings

In this paper, jitter characteristics of the BBCDR are characterized. As a result, a new equation is presented to obtain angular frequency. Also, the jitter tolerance is expressed in closed form as a function of loop parameters. The analysis is verified using behavioral simulations in MATLAB. Simulation results show that good conformance between analytical equations and simulation results.

Originality/value

The proposed approach offers two advantages compared to conventional designing methods. First, this approach does not consider any value restriction to the capacitor. Second, a new condition has been presented to guarantee that the value of jitter peaking is approximately zero.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 32 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

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