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In order to improve the accuracy of rolling bearing fault diagnosis in mechanical equipment, a new fault diagnosis method based on back propagation neural network optimized by cuckoo search algorithm is proposed. This method use the global search ability of the cuckoo search algorithm to constantly search for the best weights and thresholds, and then give it to the back propagation neural network. In this paper, wavelet packet decomposition is used for feature extraction of vibration signals. The energy values of different frequency bands are obtained through wavelet packet decomposition, and they are input as feature vectors into optimized back propagation neural network to identify different fault types of rolling bearings. Through the three sets of simulation comparison experiments of Matlab, the experimental results show that, Under the same conditions, compared with the other five models, the proposed back propagation neural network optimized by cuckoo search algorithm has the least number of training iterations and the highest diagnostic accuracy rate. And in the complex classification experiment with the same fault location but different bearing diameters, the fault recognition correct rate of the back propagation neural network optimized by cuckoo search algorithm is 96.25%.

The most common drinking water clarification technology worldwide is based on precipitation using the floccules of iron(III) oxide-hydroxide FeO(OH). The coagulation sludge obtained is usually mixed with biowaste and composted. Inexperienced farmers are interested in these composts, in the expectation that the smallest fractions of the precipitated organic matter together with the colloidal particles of clay captured during the clarification process might increase the level of soil organic matter as well as cation-exchange capacity (CEC) of soil and increase crop yields. Nevertheless, those who have used these composts observed that plants on treated soil show signs of phosphorus (P) insufficiency, despite having been fertilized appropriately. It has been published recently that the traces of iron (Fe) from the FeO(OH) turn the soil P into Fe phosphates (FeP), which makes P not readily available to agricultural plants. A 6-year field-scale experiment was carried out and was accompanied by robust analyses on soils and yields. It was confirmed that the traces of Fe from the coagulation sludge worsen the availability of soil P to plants. However, for the first time, evidence has been obtained concerning the fact that the Fe also damages the efficiency of P fertilizers applied afterward. A questionnaire was conducted among drinking water treatment plant operators and regulators to identify a reason why similar practices have not been banned yet. The results showed a growing awareness of the issue among experts, but politicians seem to prefer putting off unpopular measures. We recommend abandoning the application of these composts onto arable land and the revitalization of the affected fields using biochar activated by calcium and aluminum phosphates (CaP and AlP) so that the problem is not delayed to such an extent that its solution would become a problem for future generations.

The effect of the design parameter on the clutch engagement process of the hydro-mechanical continuously variable transmission (CVT) was investigated. First, the model of the power train was developed with the software of SimulationX, and the clutch shift experiment was used to validate the correctness of the model. Then, the friction coefficient function was fitted with the test data to get the friction coefficient model suitable for this paper. Finally, based on the evaluating index of the friction torque and the friction power, two groups of design parameters (oil pressure and friction coefficient) were simulated and explained the changing regulation theoretically. According to the simulation results, the high oil pressure and friction coefficient can reduce the slipping time. The large oil pressure can increase the peak torque but the effect of friction coefficient on the peak torque is not so significant. The friction power reaches the maximum value at 3.2 s, the peak value increases as the oil pressure and friction coefficient increase. The effect of the oil pressure on the clutch engagement and thermal performance is greater than the friction coefficient.

Foodwaste (hereinafter, FW) is the most voluminous solid waste and its amount is growing rapidly all over the world. The turning of FW into biogas via anaerobic fermentation is widely recognized as...

Infrared thermography (IRT) is a noninvasive and safe method of displaying the temperature map of objects that can be used to detect hoof diseases and lameness to reduce significant financial costs and physically stress animals. A qualitative bibliometric method based on the analysis of publications by the authors themselves using sophisticated tools of scientific databases was applied in this work. This review presents the fundamentals of IRT as well as recent developments in IRT detection in dairy science, including preprocessing, segmentation, and classification of objects in IRT images. In addition, recent studies dealing with the detection of hoof diseases and lameness using IRT are reviewed. As a result of this study, select previous studies are confronted in terms of technical aspects of IRT measurements such as emissivity, distance, temperature range, and reflected air temperature. Subsequently, recommendations for future IRT measurements are discussed.

The influence of atmospheric plasma discharge (APD) of the Gliding Arc type and low-pressure microwave plasma discharge (LPMD) on the class of various seeds was investigated. Pea, wheat, and sunflower seeds, representing legumes, cereals, and oilseeds, respectively, were selected for the treatment. Our study aimed to verify the effect of plasma treatment on the water contact angle and the wettability of the seeds. Treatment time, working gas flow and microwave power were varied to determine their impact. All treated and untreated variants were used to conduct the water contact angle measurements to compare their wettability. APD treatment seemed to be utterly ineffective for improving the wettability for most process parameters. On the contrary, LPMD manifested a much more efficient impact. The maximum effect was found for the 800 W microwave power applied to the pea seed for 30 s. The contact angle achieved decreased by approximately 50% compared to the untreated sample. These results indicate that LPMD may be an effective alternative to traditional pre-sowing seed treatments used in agriculture for water intake enhancement. Still, it is strongly dependent on the seed’s type and the used process parameters.

Nowadays, researchers are looking into next-generation biostimulants that can be designed as a dedicated agronomic tool based on plant materials. The aim of the present study was to develop a novel biostimulating product, based on plant material in the form of linseed aqueous extracts. The scope of the research included the physicochemical characterization of the product and identification of its biostimulating potential. The study has confirmed that the plant biostimulant derived from L. usitatissimum can be used as a viable agronomic tool for growing soybean. The designed and produced biostimulant is rich in bioactive compounds, including amino acids, free fatty acids, carbohydrates, and micro- and macroelements. The tested biostimulant showed significantly lower values of surface tension in relation to water and a commercial biostimulant. The soybean crops responded to the application of the preparation by improvements in agronomic and morphological levels. The linseed macerates were effective in terms of soybean yields and profitability. Our findings serve as preliminary evidence for the viability of designing and developing novel biostimulants derived from plant materials. This comprehensive approach to designing and formulating novel bioproducts necessitates more extensive and targeted research to fully explain the mechanisms behind the improvements observed in the soybean cultivation.

Minibreweries are a specific group on the Czech beer market and they communicate with their customers mostly via their product – the beer. Their main asset is uniqueness and locality. Presentation of these breweries is mostly realized by financially less difficult methods. The present text deals with the problems of marketing communication of minibreweries with respect to the techniques used. Data collection was performed via electronic questionnaire in January 2017. The researched sample consisted of 350 minibreweries as of 31st December 2016. Recoverability of the questionnaires was 41% (145 minibreweries). The aim of the research was to find out, with the help of descriptive statistic methods, which marketing tools are used by minibreweries. The results confirm that, for marketing communication, minibreweries use mostly low-cost techniques such as own web pages, which are used by 90% of the researched minibreweries, social sites by 84% of respondents, and through the renown of the minibrewery by 80% of respondents. Furthermore there are tools to be used to differentiate the product, such as labels (in 90% of respondents), glasses and beer coasters (in 85% of respondents), the least used kind of these tools being the advertisement in the national broadcast transmission (in 4% of respondents) and in the news (in 8% of respondents).

The surface modification in order to obtain hydrophobic cotton fabrics was carried out using air/HMDSO Gliding Arc plasma discharge. The dependence of the surface wettability on used process parameters, such as air flow, sample distance and treatment time were investigated. The wettability of cotton fabrics was evaluated by the drop test method by measuring the time of droplet absorption and water contact angle (WCA). The changes in the surface morphology were examined by optical microscopy and scanning electron microscopy (SEM). The treated hydrophobic fabrics were subjected to the analysis of chemical composition of the applied coatings using the ATR-FTIR spectroscopy. Hydrophobic cotton fabrics were obtained, especially with a high resistance to static wetting. In addition, the treated cotton fabrics were tested using a spray test measurement and were subjected to multiple washing.

In 2015, the effect of treatment of spring barley grain and malt produced from it with low-temperature plasma discharge on the malt gushing potential was studied. Malting barley and malt produced from it were plasma-treated. In the malt samples, the gushing potential was determined. Simultaneously, selected quality parameters were assessed in the malt samples (Kolbach index, diastatic power, β-glucan content in wort, final attenuation, extract of malt in dry matter, relative extract at 45 °C, and friability). Gushing declined in the plasma-treated samples of malting barley or malt. The malt quality parameters remained unchanged.

Powder metallurgy gears are often accompanied by broken teeth, abrasion, scratches and crack defects. In order to eliminate the defective gears in gear production and improve the yield of gears, this paper presents an improved GA–PSO algorithm, called the SHGA–PSO algorithm. Firstly, the gear images were preprocessed by bilateral filtering, and the images were segmented by the Sobel operator. Then, the geometrical shape, texture feature and color features of the sample were extracted. Next, the BP neural network was reconstructed and SHGA–PSO algorithm was used optimize its structure and weights. Finally, four different gear defect samples were brought into the neural network for calculation, and the performance of the SHGA–PSO algorithm was compared with the GA, PSO and GA–PSO algorithms. Compared with GA–BP algorithm, PSO–BP algorithm, and GA–PSO–BP algorithm, the defect diagnosis of SHGA–PSO–BP algorithm not only enhanced generalization ability, but also improved recognition accuracy.

Hydromechanical continuously variable transmission (HMCVT) is capable of bearing large torque and has wide transmission range, which is suitable for high-power tractors. Dynamic characteristics could influence the tractor life, especially in a high-power tractor. Wet clutch is the crucial component in the HMCVT, which could smooth and soft power transmission. Therefore, it is important to study the dynamic characteristics and implement the wet clutch test of HMCVT. In this paper, AMESim is used to establish virtual models of gearbox, pump-controlled hydraulic motor system, and shifting hydraulic system. Then, a simulation study of tractor operation under working condition is carried out. The internal and external meshing forces of the planetary row are analyzed. Finally, the wet clutch engagement process of HMCVT in the high-power tractor is tested to verify the oil pressure. The simulation results show that the values of internal and external meshing force become larger as the throttle opening increases. At the moment of shifting change, the meshing forces of the planetary gear have great impact. The clutch test shows that the trend of the oil filling curve obtained from the bench test is similar to that obtained from the theoretical curve, which verifies the simulation results.

The implementation of agronomic activities, based on the use of biostimulants, is an important element of agroecological practices. Therefore, comprehensive research was carried on the use of biostimulants. A field experiment was performed in 2016–2018 with common bean of Mexican Black cultivar. In particular growing seasons, bean plants were treated with Kelpak SL (seaweed extracts) and Terra Sorb Complex (free amino acids) in the form of single and double spraying with two solutions concentrations. According to the obtained data, application of biostimulants increased the yield of bean. Better results were observed after the use of Kelpak SL. The application of preparations influenced nutritional and nutraceutical quality of bean seeds. Terra Sorb Complex caused the highest increase in proteins level. In the light of achieved data, biostimulants in similar level decreased the starch accumulation. The most promising results, in the context of nutraceutical value of bean, were obtained in the case of increasing level of fiber. A positive impact of biostimulants on the seeds antioxidant potential was noted, expressed by the increased synthesis of phenolics, flavonoid, anthocyanins and antioxidant activities. Results of this study, directly indicate economic benefits from the use of biostimulants, which are extremely important to the farmers.

Production of food-grade emulsions is continuously rising globally, especially in developing countries. The steepest demand growth is in the segment of inexpensive meat products where edible emulsions serve as lubricants to mitigate economic loses linked with mechanical damage during automated processing of artificial casings. Provided that production goal is to minimize emulsion transfer into the product, its vast majority becomes voluminous greasy and sticky waste. Public sewage treatment plants cannot process such waste, its cleaning processes tends to collapse under loads of emulsions. To make matters worse, composition of emulsions often changes (according to actual pricing of main components) and emulsion manufacturers carefully guard their recipes. Therefore, running of in-house sewage plants would require continuous experimentation linked with need for skilled personnel, frequent changes in technology setup and high operating costs in general. Consequently, it was repeatedly and independently reported that emulsion waste is poured onto wildlife, resulting in environmental damage and an intense rotting odor. Three new methods of emulsion breakdown are proposed and techno-economically assessed. High versatility of methods was confirmed and multiple austerity measures were incorporated. Emulsions are also assessed in terms of an energy source for aerobic and anaerobic microorganisms. It is reported that the addition of edible emulsion to compost does not result in increased product quality or cost reduction. It is firstly revealed that edible emulsions can instantly create an anaerobic environment and accelerate biogas production through the formation of surface films on feedstock surface. Adding waste food-grade emulsions to the biogas plant makes it possible to 100% reduce process water consumption in biogas stations as the process speed can be shortened by approximately 12%.

This paper considers the evolution of processes applied in agriculture for field operations developed from non-organized handmade activities into very specialized and organized production processes. A set of new approaches based on the application of metaheuristic optimization methods and smart automatization known as Agriculture 4.0 has enabled a rapid increase in in-field operations’ productivity and offered unprecedented economic benefits. The aim of this paper is to review modern approaches to agriculture machinery movement optimization with applications in sugarcane production. Approaches based on algorithms for the division of spatial configuration, route planning or path planning, as well as approaches using cost parameters, e.g., energy, fuel and time consumption, are presented. The combination of algorithmic and economic methodologies including evaluation of the savings and investments and their cost/benefit relation is discussed.

Rolling bearings play a pivotal role in rotating machinery. The remaining useful life prediction and fault diagnosis of bearings are crucial to condition-based maintenance. However, traditional data-driven methods usually require manual extraction of features, which needs rich signal processing theory as support and is difficult to control the efficiency. In this study, a bearing remaining life prediction and fault diagnosis method based on short-time Fourier transform (STFT) and convolutional neural network (CNN) has been proposed. First, the STFT was adopted to construct time-frequency maps of the unprocessed original vibration signals that can ensure the true and effective recovery of the fault characteristics in vibration signals. Then, the training time-frequency maps were used as an input of the CNN to train the network model. Finally, the time-frequency maps of testing signals were inputted into the network model to complete the life prediction or fault identification of rolling bearings. The rolling bearing life-cycle datasets from the Intelligent Management System were applied to verify the proposed life prediction method, showing that its accuracy reaches 99.45%, and the prediction effect is good. Multiple sets of validation experiments were conducted to verify the proposed fault diagnosis method with the open datasets from Case Western Reserve University. Results show that the proposed method can effectively identify the fault classification and the accuracy can reach 95.83%. The comparison with the fault diagnosis classification effects of backpropagation (BP) neural network, particle swarm optimization-BP, and genetic algorithm-BP further proves its superiority. The proposed method in this paper is proved to have strong ability of adaptive feature extraction, life prediction, and fault identification.

Agriculture has become a sector with a huge impact on the natural environment. The interest of agriculture in the category of innovative bio-stimulants is due to the intensive search for preparations based on natural substances. This is not possible without developing and implementing innovative technologies, e.g., cold plasma, along with innovative technologies supporting farmers. Therefore, given the need to prevent environmental damage caused by intensive agriculture, plant production and protection must be targeted at merging the stimulation of crop growth and the elimination of threats to humans and the environment. The analysis of how cold plasma can influence the production of organic bio-stimulants seems to be an unavoidable step in future approaches to this topic. Since allelopathic plants represent a source of many chemical compounds promoting crop growth and development, the coupling of biologically-active compound extraction with plasma activation of allelopathic extracts has interesting potential in offering the most modern alternative to conventional agriculture. However, its implementation in practice will only be feasible after a comprehensive and thoughtful investigation of the mechanisms behind crops’ response to such bio-stimulants.

The technology for intensive broiler breeding using deep litter method provides convenient conditions for production of odour substances inside the barn. As a consequence, there are relatively high odour emissions in the breeding area and its surrounding, which has significant impacts on the life quality of both people and animals. The amount of produced emissions increases in time because it is closely related to the amount of poultry droppings accumulated in litter inside the barn. This paper deals with changes in odour intensity depending on time measured since the beginning of broiler fattening. Odour intensity was measured by methods of dynamic olfactometry. The estimated values gradually increased from 45 ouE·m-3 to the highest value of 259 ouE·m-3, which was determined in the final fattening phase (broilers’ age 33 days). The calculated odour substances emission values were in range from 0.02 ouE·s-1·bird-1 at the beginning of fattening up to 0.10 ouE·s-1·bird-1 in the final fattening phase. Odour emissions increased five times during the fattening period.

Plasma treatment is an interesting technology with many potential applications in industry. At present, more and more often we encounter papers that deal with utilization of plasma technology in food industry. This mini-review provides an overview of the latest developments in this area. At the beginning the principles of plasma interaction with solid surfaces are shortly discussed. The next chapters are focused on sterilization of food from bacteria and fungi. The infl uence of plasma treatment on the food quality and nutritional parameters is discussed in last section.

This work deals with the possibility of elimination of common occuring mycotoxins deoxynivalenol (DON) and its plant metabolite deoxynivalenol-3-glucoside (D3G) from malting barley and malt by treatment of low-temperature plasma discharge. Barley seed was treated with a fungicide, entomopathogenic and mycoparasitic fungi and the low-temperature plasma discharge of Gliding Arc type, or their combination. Samples of harvested barley were treated with plasma discharge and analyzed for presence of mycotoxins. Only low DON and D3G concentration levels were detected (maximal values were 48.2 µg/kg and 30.2 µg/kg for DON and D3G, resp.), after plasma treatment mycotoxin content decreased onto the levels near limit of quantification. The results suggest that low-temperature Gliding Arc plasma discharge may contribute to reduction of the content of the mycotoxins in harvested barley grains.

The aim of this study was to investigate a potential impact on the formation and propagation of sound from pig barns. We tested a hypothesis that the sound generated from pig housing would be influenced by the measuring distance from the barn (up to 11 m), time of day relative to feeding, building side direction, and season of year. The research was carried out in a barn for 1728 fattening pigs in the summer and winter. The measurements were made inside and outside the barn. The data were recorded before feeding (BF), during feeding (FE), and after feeding (AF). Sound levels were significantly influenced by the time of day (P

The purpose was to find effect of environmental factors (distance, feeding period, and season) on the noise emissions created from pigs housing. The measurements were made in building for 1700 fattening pigs on measuring points inside or outside of barn, always in the same time. The noise records were performed 3 times at summer and 3 times at winter season on five consecutive days and data were taken in 3 periods in relation to the feeding of pigs. Differences among periods and distances were highly significant (P

The present study was conducted to evaluate the effects of two commercial phytogenic feed additives (PFAs) on growth performance and emissions of ammonia, methane, nitrous oxide and carbon dioxide compared to an unsupplemented control. The two tested commercial PFAs contained either essential oils or a mixture of essential oils and dried herbs and spices. In addition, both PFAs delivered the same amount of Quillaja saponaria saponins to the final feed, although dosage of the products differed. The PFAs were included in cereal-based grower and finisher diets via premixes. For negative control diet a placebo premix was used. The diets were fed to a total of 81 castrated male growing-finishing pigs (45–114 kg body weight, 27 per treatment) that were kept in nine gas-tight sealed chambers, each with three pens with fully slatted floors (three pigs per pen). The whole experiment lasted 72 days. Pigs were individually weighted and the feed consumption of pigs was recorded per pen at day 0, 24 and 72 of the experiment. From day 24 to day 72 (48 days) emission measurement took place. The inclusion of the PFAs significantly improved average daily feed intake (P = 0.010) and average daily gain (P = 0.018) of pigs over the whole trial period of 72 days compared to the negative control. Feed conversion ratio was not affected by the treatments (P > 0.05). Pigs that were fed with the PFAs had 3.6% higher final body weight (P = 0.017) compared to the negative control. The inclusion of the PFAs reduced ammonia emissions per animal per day (P = 0.003) as well as per kg body weight gain of pigs (P 0.05). In summary, it might be speculated that the observed increased intake and consequently higher growth was mediated via flavoring properties of the PFAs, irrespective of differences in composition. The reduction of ammonia emissions most probably was due to the inclusion of the quillaja saponins in the PFAs. It can be concluded that the tested PFAs have a potential as performance enhancers and are useful tools for the reduction of ammonia emissions from pig barns. Further research is warranted to identify the exact modes of action of PFAs.

In order to reduce phosphorus (P) discharge into aqueous systems, wastewater treatment plants usually precipitate sludge water with iron or aluminum salts and produce slow–release P fertilizer (struvite). Continued tightening of P discharge limits require additional equipment and larger doses of these salts which increase wastewater treatment cost. Many research teams are involved in P recovery and theoretical knowledge is rapidly increasing. However, most new proposals are only economically viable with the support of public funds. Novel and technically undemanding concepts are designed and techno–economically assessed on a pilot scale. The cheapest biochar derived from fermentation residues that are pyrolyzed by waste heat, was used as sorbent. Multiple austerity measures have been designed to modify the sorbent by ferric (Fe3+) and calcium (Ca2+) chemisorption. It is firstly reported that over 2.5 kg of P per 100 kg of modified biochar from the 80 mg P L–1 environment can be obtained, whereas the P forms are more readily available to plant nutrition than struvite. Provided that a majority of used reactants are recovered from waste, or their price is irrelevant (subsequently used for their original purpose), there are indications that the newly proposed technology is one of the few environmentally friendly measures that can swiftly become widespread in the wastewater industry for economic reasons.

Global deposits of concentrated phosphates, which are a necessary source for the production of phosphate fertilizers, are limited. These reserves keep getting thinner, and every day, large amounts of phosphorus end up in watercourses. In this study, we verified that modified biochar (saturated with FeCl3 solution and then neutralized with NaOH solution) can adsorb significant amounts of phosphorus from wastewater. Moreover, the agrochemical qualities of sludge water from a municipal wastewater treatment plant, struvite, phosphorus-saturated biochar, and iron(III) phosphate from a reused biochar filter were tested in this study. We determined the amount of mobile phosphorus as well as the amount of extractable phosphorus and its five fractions. It was found that modified biochar can hold one-third of the phosphorus amount contained in the commonly used agricultural fertilizer simple superphosphate (1 × 105 g of modified biochar captures up to 2.79 × 103 g of P). Moreover, plants can more easily access phosphorus biochar fractions than struvite, which is formed spontaneously during sludge management. The results of this research prove that the proposed method of recycling phosphorus from wastewater can be applied in technological practice.

The aim of this study was to prove the hypothesis that the noise emissions from pig housing varies according to the time of day and the season. The measurements were performed in a building for 1150 fattening pigs with a slatted floor during summer and winter. The pigs (average weight 95 kg) were kept in pens under a batch management system. Nine places were the focus of sound intensity measurements (one inside the stable in section 7; eight places outside the building). The measurements were performed during three sets of 5 consecutive days in summer and three sets in winter. On each day the data were obtained during three 30 min periods (before feeding, during feeding and after feeding). The measurement was made inside and outside the building at the same time. The level of noise depends very significantly upon the period of measurement (before feeding, during feeding, after feeding). The following values were recorded inside (place 1): 65.5 ± 1.6 dB before feeding, 72.0 ± 1.4 dB during feeding and 63.4 ± 0.7 dB after feeding (P < 0.001). The effect of seasonal noise levels can be seen only in outside measurements (P < 0.05; P < 0.01). The comparison of measurement place 1 (inside, pen with pigs) with the other places outdoors showed significant differences in both observed factors (P < 0.001). We can conclude that the noise in the pig housing depends significantly on the time of day. The season influences the noise outside the building, in particular.

Mechanical devices in parlours are a source of noise, and this noise has an effect not only on the operators of the parlour but also on dairy cows. They have more sensitive hearing than humans. The aim of this article was to analyse the sound pressure level and determine the noise exposure of dairy cows at different technological solutions of milking parlours, during their day routine. In the experiment, tandem, herringbone and rotary milking parlours were used. Noise exposure was measured during the milking process. After evaluation of noise pressure levels of different types of milking parlours, it can be concluded that in this experiment, the equivalent noise pressure level was lowest in the tandem milking parlour. Equivalent sound pressure levels in the rotary and herringbone milking parlour were almost about the same values. These values are higher than values in the tandem milking parlour, about 10 decibels. The differences within mean LAFeq values between the herringbone milking parlour and tandem milking parlour were highly statistically significant (P

The recent rapid progress in development of new technologies offers new procedures, which are environmental-friendly. One of such area are modern seed-protective methods based on treatment of seeds by plasma discharges with consequent settling of the surface by protective fungi. These biotechnological approaches represent progressive practices, which may in the future reduce the amount of chemical compounds used during chemical treatment of seed. In the past decade we performed extensive laboratory research in order to establish the plasma processing parameters. In past three years the research continued by field experiments, which aimed to assess the possibility to use such approaches in real conditions. We stated that plasma treatment of seeds in combination with consecutive microbial protective coatings of grains enhances biological value of the rapeseed, when process parameters are appropriately selected. Plasma treated seeds have higher water absorbability that contributes to better germination and early growth. The plants are more robust, they have stronger root system, quicker development and maturing. And the main benefit of such approaches is, that the presented dual treatment technique results in higher yields in field experiments.

The reduction in power consumption of agricultural machinery contributes to environmental protection and sustainable development. Power consumption, wear, and stability depend on the structural parameters of the rotary blade, which are affected by three-axis resistances. Hence, the three-axis resistances were introduced as the intermediate amount; the bending angle ( x 1 ), working width ( x 2 ), and blade width ( x 3 ) were selected as factors; maximum working resistance ( F ) was taken as the index. Soil-cutting simulations were performed according to Central Composite Face-centered design (CCF). Regression equations of F in terms of x 1 , x 2 , and x 3 were established. The response surface and contour maps of the two experimental factors combined to the target were plotted separately based on Surface Response Method (RSM). The results show that the order of influence of factors on the maximum forward resistance is: x 3 , x 2 , x 1 ; vertical resistance is: x 3 , x 2 , x 1 ; lateral resistance is: x 3 , x 1 , x 2 ; the optimized parameters are x 1 120°, x 2 60 mm, and x 3 8.8 mm. Field comparison experiment show that the shaft torque and amplitude of the high-box rotary tiller are reduced by 7% and 8% respectively after optimization, and the wear per unit is reduced by 10%.

A common fluid model of ion drift in a strong electric field, appearing, e.g., in the sheath, describes ions by the Newtonian equation of motion, with ion-neutral collisions involved by an effective friction force. Such an approach implicitly anticipates a monoenergetic ion beam. We demonstrate that, due to nonlinear effects, the concept based on “average” ions is too simplified. In the suggested model, the conventional equation of ion motion is replaced by a formula considering the energy spectrum of ion flux. The formula is based on the 1-D description of charge-exchange collisions of ions with neutrals. The Newtonian equation of motion is then interpreted from the suggested collision model. It is shown that the ion fluid velocity should be identified with the rms velocity in the ion beam and that the effective ion mean free path appearing in the friction term should be chosen as a double of the ion mean free path for the charge-exchange collisions.

In this paper, an algorithm for the computational study of low-temperature argon plasma containing small micrometer-sized solid dust particulates is presented. In the first section, the numerical and computational approaches that are most frequently used in this area of research are summarized, and the references on some theoretical and experimental works are given. Consequently, we describe a hybrid model that is capable to express physical quantities depending on the electron energy distribution function (like reaction rates, diffusion coefficients, coefficients of mobility, etc.) as functions of space coordinates (x, y, z) and given time t. This way, the precision of calculation is increased in comparison with fluid modeling techniques. Some results of illustrative calculations are presented and discussed in the last section.

This paper is aimed on both the experimental and the theoretical study of textile surface modification by the plasma-enhanced chemical vapour deposition (PECVD). In the first part of this paper we describe experimental measurements of the layer profile that is deposited on the surface of a textile thread. The SEM photos of the TiO2-based layer on fibres showed that the layer thickness changes significantly with the location of the fibre in the fabric. Although both the layer thickness and its profile are crucial quantities for many technical applications, the detailed description of the layer profile experimentally is almost impossible. Therefore, a computer model was developed that enable us to predict the layer structure on the surface of the thread in fabric. This computer model can be used effectively as a sub-model in other areas of theoretical research.

The influence of the unevenness of substrates immersed into plasma important for plasma-based treatment of materials were studied by computer experiment. The role of both substrate properties and plasma parameters was investigated. For this analysis the combination of multidimensional fluid modelling and particle simulation was used. The fluid part of our model consisted of continuity equations for all charged species, energy balance equation for electrons and Poisson equation. The basic scattering processes were also included. The particle simulation technique was used both for the calculation of electron energy distribution function and for the derivation of quantities characterising plasma-surface interaction. This approach enabled us to study in detail the structure of the sheath and presheath near metal substrates with realistic geometries and finite dimensions. The main attention was devoted to the influence of substrate geometry in both macroscopic and microscopic spatial scales on the local electric fields in plasma.