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The purpose of this paper is to analyze the moisture measurement techniques presently available, as accurate determination of the moisture content (MC) of grains or any food items at right time is very important for its processing, marketing and storing.

There are basically two types of MC measurement techniques – destructive method and non-destructive method. In the time-consuming destructive method, cleaning of the food items is done and shells of food items like peanuts are removed for which man power is required and so the technique becomes costly. A literature review of the existing non-destructive methods has been done, and the methodology of each approach is explained with the figure. The less time-consuming non-destructive technique used to measure MC require less man power, as grains or food items can be directly used without any process like cleaning or crushing so that the technique become economic.

Most of the techniques used magnetic or electric properties to measure the MC indirectly. The problem with existing non-destructive technique is that measurement of MC uses only few numbers or grams of grains or food items at a time.

The farmers’ produce large quantity of grains. The small quantity of grains cannot be the representative sample for whole grains produced by the farmers. Most of the techniques use only small quantity of grains or food items at a time to measure the MC which is not accurate and representative of the produce. Also, the techniques are not simple and easily available. The cost of the techniques or arrangement to measure the MC is not reasonable.

Most of the farmers in the developing countries are financially backward. To store the agricultural produce, MC of the commodities is a key factor influencing the quality of the storage. Measurement of the MC of the seeds is thus very important for the farmers.

This paper is a review of the previous research that happened in this area, and it would help the researcher to know the techniques already been used. To the knowledge of the authors, the review of the existing moisture measurement of seeds/agricultural commodities is available in the literature.

At present, piezoelectric impedance technology has been used in the study of wood damage monitoring. However, little effort has been made in the research on the application of piezoelectric impedance system to monitor the change of wood moisture content (MC). The monitoring method of wood MC is used by piezoelectric impedance technique in this study.

One piezoceramic transducer is bonded to the surface of wood specimens. The MC of the wood specimens increases gradually from 0% to 60% with 10% increments; the mechanical impedance of the wood specimen will change, and the change in the mechanical impedance of the structure is reflected by monitoring the change in the electrical impedance of lead zirconate titanate. Therefore, this paper investigates the relationship between wood MC change and piezoelectric impedance change to verify the feasibility of the piezoelectric impedance method for monitoring wood MC change.

The experiment verified that the real part of impedance of the wood increased with the increase of wood MC. Besides, the damage index root mean square deviation is introduced to quantify the damage degree of wood under different MC. At the same time, the feasibility and validity of this experiment were verified from the side by finite element simulation. Finally, MC monitoring by piezoelectric impedance technique is feasible.

To the best of the authors’ knowledge, this work is the first to apply piezoelectric ceramics to the monitoring of wood MC, which provides a theoretical basis for the follow-up study of a wide range of wood components and even wood structure MC changes.

Many surveyors are confused about the role and accuracy of moisture meters. Draws upon extensive field experience of their use and reports the findings of laboratory testing of various materials with the most frequently used moisture meter. The meter is tested in pin probe and “search” modes on timber, PFA block, lime plaster and plasterboard. The resulting graphs help to explain what the meter reading on screen actually means and can only help surveyors get more out of the meter to diagnose dampness more effectively.

To investigate the effects of moisture and freeze‐thaw cycling on the absorption and flexural properties of rice‐hull‐polyethylene (PE) composite.

Various rice‐hull‐PE composite specimens were submerged in water at various temperatures and subjected to various freeze‐thaw cycles. Various characterisations including water absorption, bending strength and stiffness, Fourier transform infrared spectroscopy and scanning electron microscope imaging were performed.

High temperatures accelerated the water sorption of the rice‐hull‐PE composite and increased the equilibrium moisture content. The uncoated surface was not significantly more easily permeated than the coated surface, contrary to expectations. However, more water was absorbed from the cut surface than from the original extruded surface. This was attributed to the tiny checks left on the surface by the sawing action, which indicated the importance of protecting the original surface layer from scraping or other damage. Bending strength and stiffness of the rice‐hull‐PE composite decreased significantly after the freeze‐thaw cycling treatment. The modulus of elasticity decreased more than the modulus of rupture. Compared to the effect of water immersion alone, freeze‐thaw cycling treatment slightly accelerated this decrease.

The results of this study were obtained from accelerated laboratory experiments. Further research could be carried out to evaluate the properties of this rice‐hull‐PE composite in practical application.

The research revealed a possible degradation in quality when the rice‐hull‐PE composite is used in moist or freezing conditions. The resin layer on the extruded surface provides an important protection.

In China, rice‐hull powder is widely used as a reinforcing component in plastic composite. However, the durability of rice‐hull/PE composites has rarely been investigated. Results from this study will help users apply rice‐hull‐PE composites correctly and encourage the development of other agro‐fibre/polymer materials.

This paper discusses the concept of “monitoring” moisture content (MC) as a surveying aid in connection with appraisal of buildings and when assessing the drying out of buildings, for example, after flooding damage. It also presents the findings of testing of various instruments to record the drying out of brick, timber and cement screed specimens. Conclusions are drawn on the most appropriate methods for the surveyor to use when monitoring the MC of construction materials.

Fresh catfish (Clarias gariepinus) is highly perishable. This paper aims to investigate the drying characteristics and quality of body-mass dehydrated catfish to determine the effective dehydration parameters for preservation.

Brine concentration (3-9 per cent), brining time (30-90 min) and drying temperature (90-130°C) interacted using the response surface methodology. Preliminary experiments were conducted to select treatments. Moisture content and ratio and drying rate were determined and fitted into five thin-layer drying models; the goodness of fit was evaluated by average grade ranking of the regression parameters. Proximate compositions and microbial load of dehydrated catfish were determined using standard methods.

Treatments with 110°C gave initial higher drying rate (0.034-0.043 kg H₂O/kg solid/h) and shorter drying time (20-21 h). Drying occurred at two falling rate periods. Midilli model ranked first in fitting the drying data. It explained up to 99.6-99.7 per cent of the total variations in the independent variables with low values of error terms; RMSE was 0.02131-0.01794 and χ² was 0.00037-0.00043, indicating good predictive quality. Processing parameters positively and significantly (p < 0.05) influenced the proximate compositions of dehydrated catfish. Treatment: 6 per cent brine, 90 min and 110°C presented the most effective dehydration parameters for quality preservation of body-mass catfish.

The dehydration technique used in this study could enhance nutritive quality and storage stability of body-mass dehydrated catfish that could serve as a useful and convenient tool for commercial application.

Hygienically processed dehydrated catfish of good quality could be used as a source of nutrients to ameliorate malnutrition and reduce post-harvest losses of catfish.

The effective processing parameters established is an important step to harness the high nutrients and economic values embedded in catfish.

The purpose of this paper is to study various reliability measures like reliability, mean time to failure (MTTF) and sensitivity of transformer including different parameters of insulating oil/paper as health index.

The reliability characteristics of transformer incorporating different parameters of insulating oil as well as paper have been evaluated using Markov process incorporating Gumbel–Hougaard copula, Laplace transforms and supplementary variable technique. The parameters taken into consideration are breakdown voltage (BDV) and moisture content (MC) of both insulating oil and paper, and other parameters considered are interfacial tension (IFT), dissipation factor (DF), degree of polymerization (DOP) and furanic content (FC) for insulating oil and paper, respectively. By probability consideration and continuity influence, difference-differential equations have been obtained for the considered model.

Transition state probabilities, reliability, MTTF and sensitivity of the transformer corresponding to different parameters of insulating oil and paper have been evaluated with the help of aforementioned technique. Variations of reliability with respect to time along with the variations of MTTF and sensitivity have also been examined. Remarkable points during the study have also been pointed out.

Reliability characteristics of the transformer have been evaluated including two parameters: insulating oil and paper with the help of supplementary variable technique, considering two different types of repairs incorporating Gumbel–Hougaard family of copula unlike done earlier. Reliability, MTTF and sensitivity of transformer have been analyzed considering the parameters: BDV, MC, IFT and FC of insulating oil, and BDV, MC, DOP, DF of insulating paper.

This paper aims to optimize feed moisture contents, barrel temperatures, blending ratios of maize and lupine for processing of protein-rich best quality extruded product using a twin-screw extruder.

A three-factor three-level response surface methodology by Box-Behnken Design was applied to evaluate the effect of selected processing conditions of blending ratios of lupine (10-20 per cent), barrel temperatures (120°C-150°C) and feed moisture content (14-18 per cent) on functional, nutritional and sensory characteristics of produced snack food.

The results of functional properties such as radial expansion ratio, bulk density, water absorption index, water solubility index observed as 0.71-1.2, 0.33-0.92 g/cc, 4.4-6.4 per cent and 10.2-15.1 per cent, respectively. The snack food showed the moisture 5.6-7.2 per cent, protein 8.1-18.1 per cent, fiber 1.6-2.7 per cent, ash 1.6-2.2 per cent and carbohydrate 64.8-81.4 per cent. The independent variables (lupine blending ratio, barrel temperature and feed moisture content) posed significant effects on expansion ration (p = 0.0030), bulk density (p = 0.0026), water absorption index (p = 0.0075) and water-solubility index (p = 0.0116). Higher blending ratio of lupine was increase in the bulk density and water solubility index, but decrease in expansion ratio and water absorption index of snack food. Higher feed moisture content was led to a reduction in expansion ratio and water-soluble index of snack food. Whereas, higher feed moisture contents was lead to rise in bulk density and water absorption index. Fiber (p = 0.0145), ash (p = 0.0343) and carbohydrate (p = 0.0001) contents were significantly depended on blending ratio. Blending of lupine 15.06 per cent, barrel temperature of 150 °C and feed moisture content of 14.0 per cent produced the snack food with desirability value of 72.8 per cent.

Protein malnutrition is one of the major problems in child development in under developed countries including Ethiopia. Maize is a top producer in the country but least appreciated for cost. Lupine is one of the undervalued produce consumed in Ethiopia after boiling. Still data on the utilization of maize and lupine in the extruded snack preparation was very limited. Optimization of moisture and barrel temperatures for this snack was not reported clearly yet.

The physical, biomechanical and chemical properties of the composite biodegradable films are examined by their chemical composition, structure, processing conditions and economics. Therefore, the purpose of the study was to develop standard composite biodegradable films by optimizing the process (drying time and temperature) and composition (whey protein concentrate; WPC and sodium alginate; SA).

Composite WPC–SA films were developed using the Box–Behnken design of response surface methodology (RSM), with individual and interactive effects of process variables on the response variables (quality characteristics). Three independent factors at three different levels (WPC: 5–7 g, SA: 0.1–0.5 g and drying temperature: 35°C–45°C) were evaluated for their effects on physical and biomechanical properties, namely, thickness, penetrability, moisture content, water vapor transmission rate (WVTR), density, solubility, transmittance and color variables. The results were analyzed using ANOVA. For each response, second-order polynomial regression models and resulting equations were developed.

The response surface plots were constructed for representing a relationship between process parameters and responses. All responses were optimized as the best and desired, namely, thickness (180 µm), penetrability (7.63 N), moisture (28.05%), WVTR (1.87 mg/m²t), solubility (36.12%), density (1.33 g/ml), transmittance (40.55%), L* value (52.50), a* value (0.35) and b* value (13.70). The regression models exhibited “good fit” of experimental data with a high coefficient of determination. A close agreement was found between experimental and predicted values.

These biodegradable films can be promisingly used in the food packaging system without the problem of disposability.

The composite films with proteins and polysaccharides can be developed, which have improved physical and biomechanical properties.

The purpose of this paper is to predict permittivity of leafy vegetation using overlay technique.

The paper studies X band moisture dependent microwave permittivity of the stem and leaf of Ficus Bengalensis using overlay on Ag thick film microstripline. The perturbation obtained in the transmission and reflectance of the thick film microstripline due to the leafy vegetation overlay has been used to obtain the permittivity.

The paper finds that the permittivities obtained are in the range expected of leafy vegetation with moisture. Only the amplitude data have been used here. As the moisture content decreases, the dielectric constant and dielectric loss decrease. The return loss characteristics show interesting frequency dependent behaviour due to both stem and leaf overlay.

The paper is original in that a non‐resonant microstrip component has been used for the first time for such studies. The thick film component along with overlay can be a cost‐effective dielectric sensor especially for biomaterials, since any size and shape of the overlay can be used.