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The purpose of this paper is to explore the use of chiral single‐walled carbon nanotubes (SWCNTs) as mass sensors. Analysis of SWCNT with chiralities is performed using an atomistic finite element model based on a molecular structural mechanics approach.

The cantilever carbon nanotube (CNT) is modeled by considering it as a space frame structure similar to three‐dimensional beams and point masses. The elastic properties of the beam element are calculated by considering mechanical characteristics of covalent bonds between the carbon atoms in the hexagonal lattice. The mass of each beam element is assumed as point mass at nodes coinciding with carbon atoms. An atomistic simulation approach is used to find the natural frequencies and to study the effects of defect like atomic vacancies in CNTs on the resonant frequency. The migration of the atomic vacancies along the length is observed for different chiralities.

A reduction in the simulated natural frequency is observed with the maximum value occurring, when the vacancy is found nearer to the fixed end. It is quite evident from the simulation results that the effect of vacancies is significant, and the effect diminishes at 10⁻² femtograms mass. Using the higher modes of vibration of SWCNT‐based mass sensors, the amount and the position of the mass on the nanotube can be identified.

CNT have been used as mass sensors extensively. The present approach is focused to explore the use of chiral SWCNT as sensing device with vacancy defect in it. The variation of the atomic vacancies in CNT along the length has been taken and is analyzed for different chiralities. The effects of defect like atomic vacancies in CNTs on the resonant frequency have been analyzed and observed that the maximum reduction in natural frequency occurs when the vacancy is found nearer to the fixed end due to large stiffness variation.

Owing to the technology growth, especially in Microsystems technology and Nanotechnology, new products will provide new ways to sense variables that are crucial for product improvement and system reliability. A big concern of the scientific community is the measurement of low level flow measurements, especially for the biomedical and/or systems on a chip approaches.Design/methodology/approach – A new flow meter concept design consists of a surface micromachined sensor having an optical high reflective mirror made of gold, which is attached to unique cantilever designs that bend due to the drag force of mass flow. The bending of the cantilevers produces the mirror to approach/depart from an optical fiber end‐tip. The reflective light to fiber is modulated using a Fabry‐Perot interferometry technique to determine the mirror separation to the fiber, which corresponds to the mass flow.Findings – The new concept design shows a big potential approach to measure low flow measurements for air, gas and liquids of low viscosity. The results of this concept, through finite element analysis, show that the material used to build the sensor, makes them excellent candidates for fabrication. The stresses of the materials and allowable (readable) bending are among the tolerances of such materials/construction‐design. The sensor is not affected by electromagnetic interference and does not require electrical currents to sense, i.e. it is perfectly suited for biomedical and low mass‐flow sensing such as lab‐on‐chip applications.Originality/value – Among all approaches to sense low flow measurements, most of them need either “big” turbine approaches (dimensions over 1 cm diameter), or the need of an electrical approach needed in the end measurement sensor. This work proposes a non‐electrical approach.

The purpose of this paper is to develop a new vibration probe sensor for measurement of particle mass flow rate in gas–solid two phase flow.

A new vibration probe sensor based on polyvinylidene fluoride (PVDF) piezoelectric film is designed. The particle impact model according to Hertz contacting theory is presented. The average amplitude, standard deviation and spectral peak at the natural frequency of the probe (21.2 kHz) of the signals acquired through experiments are chosen as characteristic quantities for further analysis.

Through experimental study of relation between three characteristic quantities and the mass flow rate and air flow velocity, a good regularity is found in the average amplitude and the spectral peaks at natural frequency of the probe. According to the particle impact model, the structure of quantitative model is built and parameters of two models are calculated from experimental data. Additionally, tests are made to estimate mass flow rate. The average errors are 5.85 and 4.26 per cent, while the maximum errors are 10.81 and 8.65 per cent. The spectral peak at natural frequency of the probe is more applicable for mass flow rate measurement.

The sensor designed and the quantitative models established may be used in dilute phase pneumatic conveying lines of coal-fired power plants, cement manufacturing facilities and so on.

First, the new sensor is designed and the quantitative models are established. Second, the spectral peak at natural frequency of the probe is found that can be used for measurement of mass flow rate.

This paper aims to a novel fabricated resonator structure which consists of some single mechanical resonators as a mass sensor.

The structure is proposed to detect the target molecules and cells in a droplet. Also, at this design the mechanical coupling springs of the proposed structure are designed in such a way that it resonates in shear resonance mode which minimizes the damping effect.

This proposed design can be fabricated in different sizes due to the requirements of an application.

The proposed design is fabricated in mesoscale and its mass sensitivity is evaluated and reported in this paper.

The purpose of this study was to perform a complete experimental assessment of a family of oil ferrous wear debris sensor is performed. The family comprised the original sensor and its re-engineered evolution, which is capable of detecting both amount and size of wear debris particles trapped by the sensor and some predefined oil condition properties.

In this work, the first step was to perform a design of experiments for the sensor validation. A specially defined test rig was implemented, and different ferrous wear debris was collected. For each sensor, two different tests were performed. The first test was called a “void test”, where quantified amounts of debris were collided with the sensor without oil. The second one was a dynamic test, where the sensor was installed in the test rig and different amounts of wear debris were added at a constant rate. In addition, specific tests related with oil properties detection were studied.

The results show excellent correlation of the sensor output signal with the amount of wear debris and a satisfactory detection of debris size in all ranges. Also, the dynamic test presented adequate representativeness, and sensors performed well in this scenario.

This paper shows the practical implementation of this type of sensor and the usual detection range and rate of detection for different debris size and quantities.

This work has a great utility for maintenance managers and equipment designers to fully understand the potential of this type of sensor and its suitability for the application required.

This study aims to propose optimised function-based evolutionary algorithms in this research to effectively replace the traditional electronic circuitry used in linearising constant temperature anemometer (CTA) and Microbridge mass flow sensor AWM 5000.

The proposed linearisation technique effectively uses the ratiometric function for the linearisation of CTA and Microbridge mass flow sensor AWM 5000. In addition, the well-known transfer relation, namely, the King’s Law is used for the linearisation of CTA and successfully implemented using LabVIEW 7.1.

Investigational results unveil that the proposed evolutionary optimised linearisation technique performs better in linearisation of both CTA and Mass flow sensors, and hence finds applications for computer-based flow measurement/control systems.

The evolutionary optimisation algorithms such as the real-coded genetic algorithm, particle swarm optimisation algorithm, differential evolution algorithm and covariance matrix adopted evolutionary strategy algorithm are used to determine the optimal values of the parameters present in the proposed ratiometric function. The performance measures, namely, the full-scale error and mean square error are used to analyse the overall performance of the proposed approach is compared to a state of art techniques available in the literature.

The purpose of this paper is to deal with an identification of a novel ink-jet printing sensor fabrication technology for fabricating flexible carbon heaters of macro and micro sizes, carbon interdigitated (IDT) electrodes and silver IDT electrodes. The technology involved in the proposed ink-jet printing method and materials used for the formulation of homemade nano-conductive inks (digital inks) are discussed in detail. The ink-jet printed flexible carbon heaters of different sizes (macro and micro) and carbon IDT electrodes and flexible silver IDT electrodes can be used as the flexible sensing layers in electrochemical gas sensors for sensitive and selective gas sensing applications. The characterization of ink-jet printed carbon heaters on Kapton substrate and its results are discussed. Similarly, the results of formulation of silver nano-conductive ink and printing of silver IDT electrodes on Kapton and its characterization are reported here for the first time.

Flexible carbon heaters of different sizes (macro and micro), carbon micro-IDT electrodes and silver IDT electrodes patterns were developed using AutoCAD 2D and printed on the Kapton (polyimide sheet) flexible substrate using the home-made nano-conductive inks with the help of EpsonT60 commercial piezo-head-based drop-on demand technology printer with standard printing options.

The proposed novel method is able to print heater patterns and IDT electrode patterns of approximately 12 µm and approximately 1 µm thickness, respectively, on flexible substrate using the home-made nano-conductive inks of carbon and silver by using a commercial low-cost printer. The home-made nano-conductive inks can be re-used for multiple prints up to six months shelf life. The resistance of the carbon heater was measured as 88 O under normal atmospheric condition. The novel flexible carbon heater was tested for its functionality and found to be satisfactory. The resistance of the silver IDT flexible electrodes was measured as 9.5 O which is better than the earlier works carried out in this paper.

The main challenge is associated with cleaning of printing ink ejection system in the existing commercial printers. The customization of the existing printer in the near future can minimize the printing challenges.

The novel ink-jet printing technology proposed in this work is cost-effective, capable of achieving bulk production of flexible sensor elements, and consumes the least device fabrication time and high material yielding. The printing can be done with commercial piezo-head-based ink-jet printers with custom-prepared nano-conductive inks. There is a huge market potential for this paper.

Both the carbon heaters and silver IDT electrodes were printed on Kapton flexible substrate by using the commercial printer for the first time. The paper is promising the revolution in flexible low-cost sensor fabrication for mass production, and it is an alternate for thin film and thick sensor fabrication methods. The future of sensor fabrication technology will be the ink-jet printing method. In this paper, the research developments of flexible carbon heaters and flexible silver IDT electrodes for the time are reported. The characterization of carbon heaters and silver IDT electrodes were carried out and confirmed that the results are favourable for gas sensor applications.

Describes a novel system that simultaneously measures both force and acceleration, and hence deduces mass. The system has been in use on ships and at fish‐sorting plants in Japan for about 8 years. However, applications are far wider than the fishing industry and the system can be used for “weighing” moving objects. Strictly speaking, the systems deduce mass rather than weight, but for simplicity we talk about “weighing” when we really mean mass determination in order to determine weight due to gravity under static conditions.

To give a background to the automotive sensor industry and consider recent developments in sensors used in vehicle safety systems.

This paper describes the early development of the automotive sensor industry and gives examples of present‐day applications. It subsequently discusses development in advanced vehicle safety systems.

The advent of cost‐effective electronics in 1970 led to the development of numerous automotive systems such as electronic engine management which use a diversity of sensors. Since, the 1990s, safety has emerged as a major consideration and features such as traction control, ABS, stability control systems and air bags have been applied across a wide sector of the industry. New active safety systems which respond to passenger weight and position, as well as collision avoidance systems which can sense the vehicle's external environment are being developed and applied widely. These are fuelling the automotive sensor market which is forecast to reach 2.24 billion units per annum by 2010.Safety system integration is a major theme of present developments.

This paper shows that customer demands for enhanced safety have driven the development and rapid adoption of advanced vehicle safety systems. This has boosted the markets for automotive sensors.