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The article examines ways to improve the accuracy and efficiency of the production process, as well as to ensure high quality of the final product in the grain processing industry. It is shown that an automated system monitoring the properties and characteristics of bulk granular materials is required to solve the problem of insufficient quality control of grain materials. The authors consider the design features of automatic and automated systems for monitoring the properties and characteristics of bulk granular materials. The measurement methods used at grain-processing facilities are briefly described, as well as instruments for monitoring the main technological parameters. It is proposed to equip an automated grain moisture control system with a flow-through moisture meter. The physical properties of grain and grain materials are analyzed, as well as measurement conditions and instruments for grain moisture monitoring. The use of instruments relying on the dielectric method in the subsystem of an automated process control system is discussed. The article describes the application of smart sensors used in a measurement system characterized by a complex multilevel hierarchy. The interrelationship between measuring instruments designed for intelligent support in the moistening process and quality control of the materials under study is presented. The functional flow block diagram and metrological characteristics of the prototype of a grain moisture monitoring device (flow-through moisture meter) are provided. The metrological characteristics of this device meet the requirements of the grain processing industry and allow it to be used as part of a moisture control system. [ABSTRACT FROM AUTHOR]

This article reports the results of a study of the permittivity å of modified sodium silicate compositions (SSC) as a function of their content of a modifying zinc-containing aqueous solution (zinc acetate) and the curing time of the compositions. The characteristic changes in the value of å are brought to light. It is shown that for the system under study the nature of the change in å corresponds to the nature of the change in the strength and water resistance of the modified samples, depending on the content of the modifier in the SSC. Based on the material presented herein the permittivity method of assessing structural changes, modified SSC, is characterized as a quick method for predicting the properties on physicochemical modification of sodium silicate materials. [ABSTRACT FROM AUTHOR]

Abstrak Rendemen tebu umumnya ditetapkan berdasarkan nilai rendemen sementara (RS) yang tidak akurat dan rumit bagi petani. Pendugaan rendemen tebu dengan metode biolistrik, berpeluang dikembangkan menjadi solusi yang mudah, praktis, dan cepat. Akan tetapi belum terstandarnya teknik persiapan sampel untuk pengukuran sifat biolistrik tebu masih menjadi kendala. Penelitian ini bertujuan untuk menentukan standar pengukuran sifat biolistrik dan memilih sifat biolistrik yang paling berkontribusi digunakan untuk prediksi rendemen tebu. Pengukuran biolistrik (impedansi, konstanta dielektrik, dan kapasitansi) dilakukan dengan variasi panjang sampel tebu, dan frekuensi pengukuran. Sebagai tambahan, pengaruh temperatur lingkungan juga dipertimbangkan sebagai faktor koreksi. Hasil pengukuran kemudian dibandingkan dengan metode konvensional pengukuran rendemen tebu. Dari hasil eksperimen direkomendasikan standar persiapan sampel tebu yakni dengan ukuran panjang 3 cm dan frekuensi pengukuran 1000 Hz untuk pengukuran sifat biolistrik tebu. Nilai kapasitansi berpengaruh nyata terhadap nilai rendemen direkomendasikan sebagai variabel untuk mengembangkan pengukuran cepat rendemen tebu. Kata kunci: Tebu, sifat biolistrik, metode dielektrik, pengukuran cepat, rendemen Abstract Sugarcane yield is commonly determined based on the first yield (RS) which is inaccurate and considered as a complex method for the farmer. Prediction of sugarcane yield with bioelectric method have a potential to be developed as an easy, handy, and quick solution. However, unstandardized sample preparation techniques to measure bioelectrical of sugarcane still become a problem. This research aim is to determine measurement standard for bioelectric properties and select the most important properties for sugarcane yield prediction. Bioelectric properties (impedance, dielectric constant, and capacitance) measurement was carried out with variation of sample length and measurement frequency. Additionally, the effect of ambient temperature also considered as a correction factor. The results then was compared with the conventional method. The result recommend a preparation standard of sugarcane sample length is 3 cm with measurement frequency of 1000 Hz to measure the bioelectrical properties of sugarcane. The capacitance value correlated significantly to the yield that is recommeded as variable to develop rapid measurement of sugarcane yield. Keywords: Sugarcane, bioelectrical properties, dielectric method, rapid measurement, yield

After completing the production of preserved eggs, traditionally, the degree of gelling is judged by allowing workers to tap the preserved eggs with their fingers and sense the resulting oscillations. The amount of oscillation is used for the quality classification. This traditional method produces varying results owing to the differences in the sensitivity of the individual workers, who are not objective. In this study, dielectric detection technology was used to classify the preserved eggs nondestructively. The impedance in the frequency range of 2–300 kHz was resolved into resistance and reactance, and was plotted on a Nyquist diagram. Next, the diagram curve was fitted in order to obtain the equivalent circuit, and the difference in the compositions of the equivalent circuits corresponding to gelled and non-gelled preserved eggs was analyzed. A preserved egg can be considered an RLC series circuit, and its decay rate is consistent with the decay rate given by mechanical vibration theory. The Nyquist diagrams for the resistance and reactance of preserved eggs clearly showed that the resistance and reactance of gelled and non-gelled eggs were quite different, and the classification of the eggs was performed using Bayesian network (BN). The results showed that a BN classifier with two variables, i.e., resistance and reactance, can be used to classify preserved eggs as gelled or non-gelled, with an accuracy of 81.0% and a kappa value of 0.62. Thus, a BN classifier based on resistance and reactance demonstrates the ability to classify the quality of preserved egg gel. This research provides a nondestructive method for the inspection of the quality of preserved egg gel, and provides a theoretical basis for the development of an automated preserved egg inspection system that can be used as the scientific basis for the determination of the quality of preserved eggs.

The dielectric method to estimate soil moisture content is based in the existent closed relationship between dielectric permittivity and water content. The time-domain reflectometry (TDR) is an indirect technique to estimate the soil water content based on the mentioned relationship given by polynomials of different ranges inserted in the equipment. However, the absence of generalization of these models to transform the data of the sensors into readings of moisture content of different soils makes necessary the obtaining of the place-specific calibration curves. The objective of the present work consists on the calibration of a probe TDR 300 model 6430FS for its use in typical red Ferrallitic soils of Ciego de Ávila, Cuba. [ABSTRACT FROM AUTHOR]

Water mobility and availability in coffee play an important role in the roasting and storage process, depending on the interactions between the aqueous phase and the biopolymeric matrix. The aim of this research was to deepen the understanding of these aspects in green and roasted coffee, by means of the joint application of traditional saturated salt slurry (DES) and innovative dynamic dewpoint (DDI) methods for adsorption isotherm generation. In addition, on green and roasted samples at different hydration levels, the assessment of proton transverse relaxation time by TD-NMR and dielectric properties through waveguide spectroscopy in the spectral ranges 2–3, 5–6 GHz and 17–18 GHz have been performed. Green coffee exhibited above the critical a w a different behavior if observed by means of DES or DDI, demonstrating that its hydration is strictly time dependent because of its heterogeneous structure; this phenomenon was not detectable for roasted coffee, that showed very similar results with the two different techniques. The measurement of T 2 by using TD-NMR permitted to study the mobility of different proton pools with a high level of details, allowing the quantitative assessment of exchange/interaction phenomena occurring along matrix re-hydration and the consequent increase of water proton mobility. At low frequencies, the described dielectric technique showed high potentiality for the non-destructive estimation of water content of green and roasted coffee. At higher frequencies, the obtained signal seems to be more related to water/solid matrix interactions and water activity. [ABSTRACT FROM AUTHOR]

The presence of humidity in the building envelope elements decays their structural and technological properties, favours heat losses and, in time, also the deterioration and degradation of the building. In order to avoid of these aspects it is necessary to know and to mantain under control the level of humidity at the construction materials, in the process of making as well as during their exploitation; it is also necessary to be familiar with the transport phenomena of the humidity in the respective materials, thirdly it is also obligatory to monitor the spacetemporary movement of the humidity front. This article analyses an electric-dielectric method, which besides the fact that it shows, measures and monitorises the level of humidity in the construction elements, also helps to appreciate the efficiency of some surface protection systems in concordance with the german guide regarding the protection and repairing of the concrete elements. [ABSTRACT FROM AUTHOR]

The viscoelastic properties belong to the most important properties of chiral smectic liquid crystals. In this paper different methods for determination of viscoelastic properties of chiral smectic liquid crystals are compared. All of them belong to small deformation methods. The importance of the director alignment in the sample for determination of the bulk elasticity and viscosity coefficients is described. Using a typical ferroelectric in the chiral smectic C* phase we demonstrated that the correct bulk values of mentioned material constants can be determined using thick, homeotropically aligned samples only. [ABSTRACT FROM AUTHOR]

Dielectric investigations of films of different composition copolymers based on acrylonitrile (AN) with and without filler-salt LiClO4 in wide temperature–frequency ranges have been carried out. A single dipole-segmental relaxation process was observed. The region of occurrence of this α-relaxation process is shifted to higher or smaller temperatures depending on the chemical structure of the copolymers. The addition of salt LiClO4 to the copolymer films results in the decrease of the dielectrical loss factor, sharp limitation of polymer chains mobilities, shift of dipole-segmental relaxation region in the direction of higher temperatures, increase of relaxation times of the dipole-segmental process and also the appearance of two α-relaxation regions for some copolymer systems. It was caused by the formation of coordination bond between the Li+ cation and the electron pair on nitrogen atoms in the molecules of AN. The values of effective conductivities for the composites were lower then for copolymers at the temperatures T>Tg. It was caused by the increase of ion–polymer interaction. [Copyright &y& Elsevier]

Numerical assessment is made regarding Pauly and Schwan's theory which describes the dielectric behaviour of a suspension of 'shell spheres' as a model of biological membrane-bounded particles. The results indicate that approximate expressions of the theory may give rise to serious errors when applied to particles smaller than about 1 Μm in diameter. With a view to performing analysis according to a general expression of the theory, some of the characteristic responses of dielectric parameters upon changes in phase parameters are examined with particular reference to some numerical ranges of biological interest. On this basis a simplified and systematic procedure is proposed for estimating the phase parameters of particles whose shell phase can be regarded as non-conductive. As the application of the procedure proposed, a set of dielectric data of a synaptosome suspension is analyzed, so that the following three phase parameters are successfully determined: membrane capacitance (or shell phase dielectric constant), internal phase conductivity and internal phase dielectric constant. Some limitations of the procedure are discussed for the cases of conducting shells and small particles. [ABSTRACT FROM AUTHOR]

After completing the production of preserved eggs, traditionally, the degree of gelling is judged by allowing workers to tap the preserved eggs with their fingers and sense the resulting oscillations. The amount of oscillation is used for the quality classification. This traditional method produces varying results owing to the differences in the sensitivity of the individual workers, who are not objective. In this study, dielectric detection technology was used to classify the preserved eggs nondestructively. The impedance in the frequency range of 2–300 kHz was resolved into resistance and reactance, and was plotted on a Nyquist diagram. Next, the diagram curve was fitted in order to obtain the equivalent circuit, and the difference in the compositions of the equivalent circuits corresponding to gelled and non-gelled preserved eggs was analyzed. A preserved egg can be considered an RLC series circuit, and its decay rate is consistent with the decay rate given by mechanical vibration theory. The Nyquist diagrams for the resistance and reactance of preserved eggs clearly showed that the resistance and reactance of gelled and non-gelled eggs were quite different, and the classification of the eggs was performed using Bayesian network (BN). The results showed that a BN classifier with two variables, i.e., resistance and reactance, can be used to classify preserved eggs as gelled or non-gelled, with an accuracy of 81.0% and a kappa value of 0.62. Thus, a BN classifier based on resistance and reactance demonstrates the ability to classify the quality of preserved egg gel. This research provides a nondestructive method for the inspection of the quality of preserved egg gel, and provides a theoretical basis for the development of an automated preserved egg inspection system that can be used as the scientific basis for the determination of the quality of preserved eggs. [ABSTRACT FROM AUTHOR]