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In this paper, a new efficient method to de-noise the interferometric Synthetic Aperture Radar interferogram, also called wrapped phase image, is proposed with the aim to reduce the residue number and make the phase unwrapping process easy.

This method is based on two statistics functions, the former is the phase derivative variance (PDV) defined as a quality map to select the badness areas, the second one is the phase derivative variance (PAD) for a local 3 × 3 pixels filtering which allows to assign an estimated phase for each bad area selected by PDV function. Our filter was tested with a simulated interferograms and compared to other most used filters.

With this proposed method, the residues in the interferogram are minimized better than using a conventional filters, and the phase unwrapping process gives a better estimation.

Combining two statistical functions (PDV and PAD) is efficient in terms of minimizing the noise in the interferogram; this is very helpful to minimize the processing time of the InSAR image particularly the phase unwrapping treatment and have a good quality of the image.

Filter design plays an essential role in most communication standards. The essential element of the software-defined radio is a channelizer that comprises several channel filters. Designing filters with lower complexity, minimized area and enhanced speed is a demanding task in currently prevailing communication standards. This study aims to propose an efficient reconfigurable residue number system (RNS)-based multiply-accumulate (MAC) channel filter for software radio receivers.

RNS-based pipelined MAC module for the realization of channel finite impulse response (FIR) filter architecture is considered in this work. Further, the use of a single adder and single multiplier for realizing the filter architecture regardless of the number of taps offers effective resource sharing. This design provides significant improvement in speed of operation as well as a reduction in area complexity.

In this paper, two major tasks have been considered: first, the RNS number conversion is performed in which the integer is converted into several residues. These residues are processed in parallel and are applied to the MAC-FIR filter architecture. Second, the MAC filter architecture involves pipelining, which enhances the speed of operation to a significant extent. Also, the time-sharing-based design incorporates a single partial product-based shift and add multiplier and single adder, which provide a low complex design. The results show that the proposed 16-tap RNS-based pipelined MAC sub-filter achieves significant improvement in speed as well as 89.87% area optimization when examined with the conventional RNS-based FIR filter structure.

The proposed MAC-FIR filter architecture provides good performance in terms of complexity and speed of operation because of the use of the RNS scheme with pipelining and partial product-based shift and adds multiplier and single adder when examining with the conventional designs. The reported architecture can be used in software radios.

Powder bed fusion (PBF) additive manufacturing (AM) has facilitated the production of medical devices with intricate geometries and patient-matched features. The medical industry especially has leveraged complex geometries for orthopedic applications. However, these geometries increase the difficulty of manufacturing residue removal. Furthermore, PBF-specific methods for residue removal and quantification have not been developed yet. This study aims to assess the use of a novel challenge assembly to evaluate PBF residue removal protocols.

A novel modular PBF challenge assembly was evaluated for its ability to resolve differences in the residue removal techniques. Several metrics were adapted from consensus standards and applied to evaluate their suitability. Though the challenge assembly can incorporate multiple complex geometries and reticulated structures, this study used the test case of regular lattice structures and two generic residue removal protocols (RRPs).

The challenge assembly successfully represented increasingly complex residue removal scenarios, showing increasing amounts of residue remaining in parts of increasing density. Simultaneous examination of multiple geometries with different residue removal difficulties can be used to design production processes. Indirect estimates of extracted residue provided some information on residue remaining. However, they were not sufficient to evaluate the part because of the high variability and uncertainty. Additional metrics proved necessary to corroborate the results during a verification phase. A carefully selected panel of metrics could provide adequate information to validate a process.

This study evaluated and demonstrated a framework to assess RRPs for complex geometries. It showed that the results of single indirect metrics such as extracted residues may provide ambiguous results across a range of parts. PBF-specific metrics for residue removal and quantification would greatly improve repeatability and certainty.

The purpose of this paper is to present analysis of the feedback predictive encoder-based analog-to-digital converter (ADC).

The use of feedback predictive encoder-based ADCs presents an alternative to the traditional two-stage pipeline ADC by replacing the input estimate producing first stage of the pipeline with a predictive loop that also produces an estimate of the input signal.

The overload condition for feedback predictive encoder ADCs is dependent on input signal amplitude and frequency, system gain and filter order. The limitation on the practical usable filter order is set by limit cycle oscillation. A boundary condition is defined for determination of maximum usable filter order. In a practical implementation of the predictive encoder ADC, the time allocated to the key functions of the gain stage and loop quantizer leads to optimization of the power consumption.

A practical switched capacitor implementation of the predictive encoder-based ADC is proposed. The power consumption of key circuit blocks is investigated.

This paper presents a methodology to optimize the bandwidth of predictive encoder ADCs. The overload and stability conditions may be used to determine the maximum input signal bandwidth for a given loop quantizer. Optimization of power consumption based on the allocation of time between the gain stage and the successive approximation register ADC operation is investigated. The lower bound of power consumption for this architecture is estimated.

The Department of National Health and Welfare, Canada, has recently issued a most useful guide to manufacturers, advertisers and importers of food, drugs and cosmetics. The guide has been produced by the Inspection Services of the Food and Drug Directorate. This Department is in the habit of giving advice and opinions to manufacturers who submit labels or advertisements for its consideration, and sometimes suggests modifications thought likely to be satisfactory. The Department has no power to give actual approval or to usurp the function of Courts of Law. In general, there is a great similarity between the requirements of the Dominion and those of Great Britain in the matter of labels and advertisements. But Canada—very wisely, as we think—has not followed the bad example set in the mother country by the Ministry of Food a few years ago when—in defiance of the opinions of nearly all competent persons—the Ministry suddenly decided to emasculate its Food Standards and Labelling Division. The present position is that the admirably informative and helpful yellow book, published in 1949, is now out of date and that manufacturers for years have been unable to obtain the guidance and assistance which used to be available from the Ministry. There have been recent signs that the Minister of Agriculture, Fisheries and Food may be willing before long to issue some guidance to the British public which will protect them against imposture. As is shown by the sea‐salmon prosecution reported at page 84, there is still plenty of scope for such protection. We have no doubt that as soon as the consolidated Food and Drugs Acts—that for Scotland as well as that for the remainder of the United Kingdom—and the Regulations to be made under them have become effective, a comprehensive guide, based on the yellow book of 1949, ought to be issued by the Ministry in the interests of traders and consumers. We are less sure that it will be.

The purpose of this paper is to model and to value a temperature derivative to hedge late frost risk in viticulture.

Starting from 11 years of historical temperature data collected in Mendoza, Argentina, the authors reconstruct the missing data using principal component analysis. The frequency content of time series is examined by the periodogram method; ordinary least squares are used to estimate the trends of minimum, maximum and average temperatures, and hypothesis tests of univariate and bivariate normality are performed on deseasonalized and filtered temperature returns. The authors express the temperature dynamics by correlated Ornstein‐Uhlenbeck processes and historical data were fitted into the model to obtain parameters estimates. An Asian‐type option on a temperature index is constructed and its price and sensitivities are computed by Monte Carlo method.

The authors define an index in terms of minimum and average temperatures that, under some simplifying hypotheses, quantifies the damage produced by a late frost. To hedge the late frost risk, an Asian‐type option on the index is constructed. Together with the results concerning the design and pricing of the option, the analysis of historical data reveals non‐negligible linear trends, negative in minimum temperature and positive in maximum and average temperatures. These findings may be consistent with the hypothesis of global warming or with the presence of out‐of‐phase very low frequency components.

The authors have not found in the literature a similar option to hedge the risk of spring frosts faced by fruit producers.

Organic cotton, which is produced without any chemical fertilizers and pesticides, is playing a vital role in creating a less harmful environment. An investigation of the properties of weft knitted fabrics produced from organically made cotton vis-à-vis regular cotton knitted fabric is reported. The yarn is made with both organically produced and regular cotton, and the fabric is knitted by using single jersey machines. The fabrics are subsequently dyed by using natural dyes. The naturally dyed knitted fabrics are examined for shrinkage, bursting strength, abrasion resistance, and colour fastness properties. The result shows that the knitted fabrics produced from organically grown cotton is superior in performance in comparison with fabrics produced from regular cotton.

The purpose of this paper is to explore the previously unreported phenomenon in which changes occur to the particle size distributions of calcium carbonate fillers, used in papermaking, when exposed to high intensity ultrasound.

Commercial paper pulps sonicated at a frequency of 20 kHz are found to produce aggregates of their mineral filler constituents. The effects of sonication on isolated long and short fibre, and ground and precipitated calcium carbonate filler systems are also investigated both with and without the presence of dispersants. The findings are supported by particle size analysis and scanning electron microscopy of the sonicated systems.

It is clearly shown that exposure to high intensity ultrasound induces filler aggregation. However, the effect only occurs when paper fibres and fillers coexist and is not apparent for suspensions of filler only or fibre only slurries. Furthermore, the treatment overrides the effect of dispersants used to keep filler in suspension during the manufacturing process. An accompanying fall in pH with increasing sonication times is also noted and is linked to these changes. It is proposed that radical species produced in the slurries during sonication may explain the observed phenomenon.

The role of pH is not clearly understood and needs further study.

The findings may be of interest in paper manufacture where uniform dispersal of fillers throughout the pulp is of significant importance.

The phenomenon described in this paper has not previously been reported or explored. Further studies may add to knowledge of filler dispersions and their behaviour in papermaking.

The purpose of this paper is to present the application of Hilbert–Huang transform (HHT) for fatigue damage feature characterisation in the time–frequency domain based on strain signals obtained from the automotive coil springs.

HHT was employed to detect the temporary changes in frequency characteristics of the vibration response of the signals. The extraction successfully reduced the length of the original signal to 40 per cent, whereas the fatigue damage was retained. The analysis process for this work is divided into three stages: signal characterisation with the application of fatigue data editing (FDE) for fatigue life assessment, empirical mode decomposition with Hilbert transform, an energy–time–frequency distribution analysis of each intrinsic mode function (IMF).

The edited signal had a time length of 72.5 s, which was 40 per cent lower than the original signal. Both signals were retained statistically with close mean, root-mean-square and kurtosis value. FDE improved the fatigue life, and the extraction did not affect the content and behaviour of the original signal because the editing technique only removed the minimal fatigue damage potential. HHT helped to remove unnecessary noise in the recorded signals. EMD produced sets of IMFs that indicated the differences between the original signal and mean of the signal to produce new components. The low-frequency energy was expected to cause large damage, whereas the high-frequency energy will cause small damage.

HHT and EMD can be used in the strain data signal analysis of the automotive component of a suspension system. This is to improve the fatigue life, where the extraction did not affect the content and behaviour of the original signal because the editing technique only removed the minimal fatigue damage potential.

Translating the conceptual basis of dietary fibre into a definition that can be used as the basis for practicable analytical methods has been a matter for considerable debate amongst those involved in dietary fibre measurements. The original authors used the term “dietary fibre” for the plant cell wall material in foods and this provides the most satisfactory starting point in any discussion on analysis. Compares the two most widely used approaches for the measurement of dietary fibre and considers their bases in relation to the conceptual origin of dietary fibre as a protective factor in the diet.