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The purpose of this paper is to demonstrate the theoretical relationship between the layout of four‐sensor dynamic acoustic array tracking system and systematic observation accuracy, and provide an algorithm to determine the optimal arrangement of four‐sensor acoustic array and an indicator to evaluate acoustic array system measurement accuracy.

In the present paper, the measurement principle of the four‐sensor dynamic acoustic array tracking system is analyzed, and the system observation model and the conversion relationship between models are established. Subsequently, the optimization algorithm for the four‐sensor dynamic acoustic array is deduced, the theoretical optimal arrangement of the four‐sensor dynamic acoustic array tracking measurement system is obtained based on the optimal position dilution of precision function (PDOPF) of 2D target, and the static experimental study on sound‐source bearing estimation is designed. The theoretical results are compared with the experimental results of the present study.

The measurement accuracy of the four‐sensor dynamic acoustic array tracking system is largely dependent on the layout of the acoustic sensor. Theoretical studies and experimental results demonstrated that an optimal PDPOF can be used to analyze the rationality of the layout. It can also serve as an indicator for the layout of the four‐sensor dynamic acoustic array tracking system.

The PDOPF value is presented as an indicator for the evaluation of the four‐sensor dynamic acoustic array systematic observation accuracy based on theoretical analysis. The feasibility of the indicator and the rationality of the sensor layout in practical engineering application are verified through experimental studies on sound‐source bearing estimation. The higher the PDOPF value is, the lower the accuracy of the system will be.

Nanopore-based molecular sensing and measurement, specifically DNA sequencing, is advancing at a fast pace. Some embodiments have matured from coarse particle counters to enabling full human genome assembly. This evolution has been powered not only by improvements in the sensors themselves, but also in the assisting microelectronic CMOS readout circuitry closely interfaced to them. In this light, this paper aims to review established and emerging nanopore-based sensing modalities considered for DNA sequencing and CMOS microelectronic methods currently being used.

Readout and amplifier circuits, which are potentially appropriate for conditioning and conversion of nanopore signals for downstream processing, are studied. Furthermore, arrayed CMOS readout implementations are focused on and the relevant status of the nanopore sensor technology is reviewed as well.

Ion channel nanopore devices have unique properties compared with other electrochemical cells. Currently biological nanopores are the only variants reported which can be used for actual DNA sequencing. The translocation rate of DNA through such pores, the current range at which these cells operate on and the cell capacitance effect, all impose the necessity of using low-noise circuits in the process of signal detection. The requirement of using in-pixel low-noise circuits in turn tends to impose challenges in the implementation of large size arrays.

The study presents an overview on the readout circuits used for signal acquisition in electrochemical cell arrays and investigates the specific requirements necessary for implementation of nanopore-type electrochemical cell amplifiers and their associated readout electronics.

The primary purpose of this paper is to explore possible locations for parity cache within disk array model and describe the disk array model development process.

A dynamic, discrete event simulation model, based on modular, bottom‐up approach, is initiated from a single disk, and then extended on disk array.

Parity information within array model cannot be stored on individual disk cache, instead it should be stored in array cache. If model is used for simulation of single disk array then an approach with separate parity cache should be used, while an approach where a parity cache is part of array cache should be used for simulation of more complex storage systems with numerous arrays.

The proposed model does not include any read‐ahead cache policy, and only a full‐stripe writes can be performed. As a result, the model should be used only for sequential read or write of large files because then those limitations do not influence simulation output.

The novelty depicted in this paper is an approach, in array modelling, with parity cache merged into array cache. Also, the achieved bandwidth for the resulting simulation model differs from 1.05 to 1.7 per cent from the measured one on the experimental array.

The prediction of critical velocity at instability threshold for shell and tube heat exchangers is important to avoid failure of tubes as a result of flow-induced vibrations due to water cross flow. The flow-induced vibration in finned tube heat exchangers is affected by various parameters such as fin height, fin pitch, fin material, tube array, pitch ratio, fin type, fluid velocity etc. In this paper, an experimental investigation of fluid elastic instability in shell and tube heat exchangers is carried out by subjecting normal square finned tube arrays of pitch ratio 1.79 to water cross flow.

The five tube arrays, namely plain array, two finned tube arrays with 3 fpi and 9 fpi fin density, and two finned tube arrays with 3 mm and 6 mm fin height are tested in the experimental test setup with water flow loop and vibration measurement system. The research objective is to evaluate the effect of fin density and fin height on the instability threshold. The critical velocity at instability threshold is determined to characterize the fluid elastic instability behavior of different tube arrays. The vortex shedding behavior of the tube arrays is also studied by determining Strouhal number corresponding to the small peaks before fluid elastic instability.

The fluid elastic instability behavior of the tube arrays was found to be the function of fin tube parameters. The experimental results indicate that an increase in fin density and fin height results in delaying the instability threshold for finned tube arrays. It is also observed that critical velocity at instability is increased for finned tube arrays compared to plain tube arrays of the same pitch ratio. The design modifications in the outer box have resulted in further reduction in the natural frequency. This enabled to reach clear instability for all the five-tube arrays.

The research data add the value to the present body of knowledge by knowing the effect of fin height and fin density on the fluid elastic instability threshold of normal square finned tube arrays subjected to water cross flow.

The purpose of this paper is to propose an automatic optical inspection system for measuring the surface profile of a microlens array.

The system set‐up was constructed according to the principle of the Fizeau interferometer. After capturing the ring interference fringe images of the microlens with a camera, the diameter, profile information and optical properties were analyzed through a microlens surface profile algorithm using innovative image pre‐processing with a precision of less than 0.09 micron.

By integrating with the genetic algorithm, the XY‐Table shortest moving path of the system is calculated to achieve the purpose of high‐speed inspection and automatic microlens array surface profile measurement.

The measurement results of this system were also compared with other systems, including the atomic force microscope and stylus profiler, to verify the measurement precision and accuracy of this system.

High‐frequency transducer arrays that can operate at frequencies above 30 MHz are needed for high‐resolution medical ultrasound imaging. The fabrication of such devices is challenging not only because of the fine‐scale piezocomposite fabrication typically required but also because of the small size of arrays and their interconnects. The purpose of this paper is to present an overview of research to develop solutions for several of the major problems in high‐frequency ultrasound array fabrication.

Net‐shape 1‐3 piezocomposites operating above 40 MHz are developed. High‐quality surface finishing makes photolithographic patterning of the array electrodes on these fine scale piezocomposites possible, thus establishing a fabrication methodology for high‐frequency kerfless ultrasound arrays.

Structured processes are developed and prototype components are made with them, demonstrating the viability of the selected fabrication approach. A 20‐element array operating at 30 MHz is patterned and characterised. Furthermore, an electrode pattern suitable for a 20‐element array operating at 100 MHz is created to demonstrate the state of the art of photolithography processing directly on piezocomposite.

The work reported suggests that ultrasound arrays for real‐time biomedical imaging will be viable at higher frequencies than presently available commercially or previously reported in the research literature.

The main elements of a novel, fully mask‐based process for high‐frequency ultrasound transducer array fabrication are presented in outline in this paper.

The purpose of this paper is to improve the accuracy of innovative current transducers based on magnetic sensor arrays.

The positions and the orientations of the magnetic sensors are optimized. The objective function is defined according to D‐optimality theory and the optimization problem solved using particle swarm optimization (PSO).

PSO is shown to be efficient for the optimization problem and that, following the D‐optimality approach, a significant improvement in the measurement accuracy is obtained in terms of the errors typically used to classify current transducers.

The paper does not take into account the effects of external magnetic fields.

A criterion and a methodology are suggested in order to design more accurate current transducers based on magnetic sensors.

A new methodology to optimize magnetic sensor arrays for current measurement.

The purpose of this paper is to present an optimization process for the design of a 2×2 patch antenna phased array with application for an UHF RFID system.

The optimization process is based on a method of moment (MoM)-solver, which was individually made to create such patch antenna phased arrays and simulate the radiated field pattern. In combination with this MoM-solver, a GUI, which gives the opportunity to change every physical antenna factor and create the antenna structure within a few minutes is presented. Furthermore the golden section search method is used to produce an even better solution in a more efficient way compared to the first attempt. After the simulation, different types of presentation of results can be chosen for a fast and easy optimization.

The design process is discussed while the authors try to optimize the distance between the elements and the difference of input phase for each patch element. The final goal is to create an antenna with maximum directivity and coverage of field pattern.

A physical implementation of an optimized patch antenna phased array and the results of measurement are presented in the end.

An optimization process for the design of a 2×2 patch antenna phased array with application for an UHF RFID system is presented. Furthermore the golden section search method is combined with the design process to increase the accuracy of the solution and decrease the time effort.

The purpose of this paper is to propose an improved reconfigurable zero‐IF RF receiver with anti‐interference improvement used in dynamic spectrum resource sharing system at UHF band based on tunable filter array computation. Measured results show that the anti‐interference competence of improved zero‐IF RF receiver is enhanced greatly by employing two tunable filter arrays.

The anti‐interference reconfigurable zero‐IF RF receiver is based on fully differential I/Q demodulation structure and employs two same tunable filter arrays to meet the requirement on adjacent channel suppression imposed by systems coexisting. The performance requirement of each filter in tunable filter arrays is computed and derived according to the needs of anti‐interference.

The anti‐interference competence of zero‐IF RF receiver could be enhanced greatly by employing two tunable filter arrays.

The paper provides a method to design zero‐IF RF receivers with anti‐interference competence used in dynamic spectrum resource sharing systems.

The paper is concerned with exploration of sensor signals in differential electronic nose. It is a special type of nose, which applies double sensor matrices and exploits only their differential signals, which are used in recognition of patterns associated with them. The purpose of this paper is to study the application of differential nose in dynamic measurement of aroma of 11 brands of cigarettes.

The most important task in pattern recognition using electronic nose is its resistance to the noise corrupting the measurement. The authors will analyze and compare the performance of the nose in the noisy environment by applying two classifier systems: the support vector machine (SVM) and random forest (RF) of decision trees.

On the basis of numerical experiments the authors have found that application of SVM as the classifier in the electronic nose is more advantageous than RF, especially at high level of noise and small number of measuring sensors. Its application allowed to recognize 11 brands of cigarettes with the accuracy close to 100 percent.

Thanks to application of two identical sensors working in a differential mode the authors avoid the baseline estimation and thus the solution is well suited for on-line dynamic measurements of the process.

The paper has studied the advantages and limitations of the differential electronic nose following from the existence of the noise, corrupting the measurements. It has pointed an important role of the applied classifier system in getting the electronic nose of the highest quality.