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Multi-Fuel Power Plant as A Element of Back-Up Energy Supply of Farming Facilities

Abstract

Paper presents research concerned utilization of natural gas in a liquid state as a new source of electrical energy generation in country side areas of Russia to use it in a small family farms and bigger agriculture enterprises. The experiment shows that alcohol and gasoline are more expensive products to be a source for electricity generation as a reserve energy supply in agriculture production areas of the country. Introduction of natural gas generator as an alternative fuel makes possible to produce low cost of electrical energy in any part of the country, what gives great potential to alternative energy supply, but especially for agriculture production on small households and also bigger enterprises

Open access
Optimisation of Osmotic Dehydration of Plums

Abstract

The paper presents kinetics of osmotic dehydration of plums in relation to the treatment time and concentration of sucrose solution. The main aim of the study was polyoptimisation of the preservation process, namely selection of optimal parameters of osmotic dehydration processes including changes in selected quality indicators. Defining of optimal conditions of the entire course of preservation may influence limitation of consumption of preserving substances (osmotic substances) and reduction of the energy demand. Based on the research which was carried out, it was found that parameters of osmotic dehydration had a significant impact on mass transfer coefficients and physico-chemical indicators of fruit - along with the increase of concentration of osmotic solution and extension of the time of the process, the increase of the investigated sizes was observed. In the second part of the paper, optimization of the fruit preservation process was performed. The idea of the objective function consisted in minimization of the difference between the expected values of criteria and the values obtained from the experimental results. For the defined scalar optimization criterion an explicit relation between quality and cost of the product was showed.

Open access
Prediction of Pre-Compression Stress of Soil with Uniaxial Test

Abstract

The paper presents a concept of determination of pre-compression stress. It assumes that the stress value is close to the unit pressure value which is indispensable to increase the initial degree of soil compaction. Thus, an attempt was made to develop an empirical model for predicting the value of stress at which the initial compaction of a soil sample increases by a determined value. Samples with the so-called intact structure (NS) and soil material in the form of loose mass were collected from subsoil, and they were used to form model samples. Both types of samples were uniaxially compressed. For the study, data on moisture and dry bulk density of model samples were used, as well as determined ratios (conversion factors) that present relations between the results of compaction of model samples and samples with the intact structure. It was reported that the pressure necessary for the increase of the initial compaction of the model samples with the value of +0.05 or +0.10 g∙cm−3 were higher than the formation pressure respectively by 1.03-1.11 and 1.42-1.93 times. It was proved that for determination of the pre-compression stress of the NS samples models of linear regression for prediction the pressure needed to increase the initial compaction of the model sample by the value of +0.05 g∙cm−3, combined with a coefficient calculated for the present state of the soil properties, can be applied.

Open access
Research Resoults of Grain Shredder by Using Multiplied Method of Evaluation

Abstract

Currently in Russia and other countries in family farms there is a demand for lowering cost of animal production. Main direction to achieve new terchnological solutions characterized by low energy constumption and high efficiency with maintaining high quality of product (mineral). For example, lately in animal production are acquired concentrates with low unity costs. Realising targets releated with lowering costs of forage production with usage comminution and crease of grain. Previously conducted own researches and literature analises shows, that currently used solutions are characterized by big errors made by construction of the devices, and technology effect of obtained product (grain). The paper presents the criteria for optimalization of technical indicators of shredding devices affecting the quality of the product.

Open access
Reversible Supply Chain in function of competitiveness

Abstract

Supply Chain makes the flow of goods, services and information from suppliers, through transport, producers, distributors, retailers to end customers. Big producers opt for a strategy of outsourcing logistic services, especially storage, delivery, and distribution services to end-customers. Commitment to the strategy of outsourcing, at the same time, is the strategy of focus on the core business. Small producers, especially manufacturers of agricultural food products, have recently opted to avoid intermediaries in the transport and distribution of the product to the end customer. All in order to increase the quality of their own products and increase the competitiveness by eliminating the costs of intermediaries in transport and distribution. This is achieved by merging and shortening the supply chain. The EU has established an institutional framework regulating the operations of producers through a short supply chain. The market situation requires further optimization by producers due to lack of labour and the need to increase competitiveness and leads to the emergence of a reversible supply chain phenomenon. In the paper, the author, by applying general and special scientific methods of cognition, explores the advantages and shortcomings of the short and reversible supply chain, derived from the traditional and modern supply chain model.

Open access
Shaping Teat Suction Forces of Liners with Varied Structure of Rubber Core

Abstract

A liner is the only part of the milking unit which has a direct contact with a cow’s teat. It ensures a correct circulation of body liquids in a teat with its suitable massage and creates conditions for a teat to open and milk to flow out and maintains a milking cup on a teat. The result of the last task is generation of a suction force that sucks a teat into a liner. During milking, when a cup is placed on a teat, counter forces are generated that try to remove a liner from a teat and forces that cause that a teat moves up to a liner producing a phenomenon of “a climbing cup”. Forces that tend to separate a teat from a liner depend on the mass of a milking cup set and the value of the friction force. A counter force that tends to suck a teat into a liner is proportional to the level of negative pressure in a liner and the surface of cross-section of a teat that is subjected to negative pressure. We should also assume that also the structure of a liner will influence this force. The paper presents results of the laboratory tests on the impact of the shape of the cross-section of a rubber core and construction solutions of liners on the vacuum force of a liner when a teat is sucked into a teat chamber. Eight liners, popular in milking machines used in our country were used in the tests. Various penetrations of a teat (50, 62, 75 and 100 mm), working pressure (25-55 kPa) and a working stage of the milking cup were additional variables. In order to determine whether and what is the degree of the impact of variability sources on shaping the suction forces of a liner, a static processing of results was carried out using a multi-variance analysis. It was proved that at the significance level of α=0.05, the source of variability assumed in the experiment in the form of the liner shape, negative pressure and penetration affected the analysed sizes, i.e. Average values of suction forces in the suction phase (Fws) and massage phase (Fwm). The investigation of the impact of the rubber core part on the determined values of the suction force in the function of variable negative pressure proved that at teat penetration of 50 and 62 mm (the most popular lengths of teats in milked cows), the lowest suction force was observed in case of a liner with a triangular cross-section, slightly bigger with a square cross-section and the highest suction force is generated by round and oval liners.

Open access
Spectrometric Determination of Content of Methyl Palmitate in Methyl Esters of Waste Cooking Oils

Abstract

The second-generation liquid biofuels are fuels derived from non-food raw materials, i.e. waste cooking oils and animal fats. They are waste raw materials from the agri-food industry, hence their quantity is limited, and their quality depends, inter alia, on the place of their acquisition. Considering the fact that rheological properties of liquid biofuels are closely correlated with the quality of raw materials from which they are obtained, the industrial production of biofuels from waste fats requires development of new analytical methods, allowing for a quick assessment of the quality of the obtained products. The aim of the study was to confirm the possibility of using near infrared spectrometry to assess the content of methyl palmitate in biofuels produced from waste cooking oil. The calibration models were based on 41 absorbance spectra recorded in the range of 400-2170 nm for samples containing from 0 to 5 % of methyl palmitate. The obtained results confirmed that there is a possibility of effective detection of the concentration of this ester in biofuel using the spectrum in the range of 1644-1778 nm. The developed PLS calibration models are characterized by a determination co-efficient (R2) exceeding the value of 0.99.

Open access
Waste Management Integration with Green Quality Function Deployment (G-QFD) for Healthcare Centre

Abstract

High doses of medical waste evidence that health waste management is problematic. A case study was conducted at various health institutions. This research analyzes various issues in the area of medical waste management. The research examines the perception of staff regarding medical waste management. The purpose of the study is to investigate the level of knowledge, attitudes and role of health practitioners in the management of medical waste.

Here the quality index and the environmental index of two health centers are studied; one is a private hospital and the other one a state hospital and compares these two indices with a questionnaire.

To provide environmentally friendly services, customers and environmental criteria have to be taken into account in the decision-making process and distributing the Green Quality Function provides a very useful way to achieve this goal.

Open access
Application of FKM Calculation Algorithm for Determination of Degree of Utilization of A Milk Tank Wall

Abstract

The objective of the paper was to determine the level of circumferential stress in a wall of an open milk tank and to assess the tank wall degree of utilization according to the FKM Guideline calculation algorithm − Analytical Strength Assessment of Components, Made of Steel Cast Iron and Aluminium Materials in Mechanical Engineering. (German: FKM – Forschungskuratorium für Maschinenbau). The stress level in the tank wall was determined based on analytical calculations and numerical method using the FEA – Finite Elements Analysis. Numerical calculations were made in FEMAP with NX NASTRAN Solver (NASTRAN – NASA Structure Analysis). Similar stress values were found using two independent calculation methods. The difference between obtained stress values does not exceed 2%. Based on the FKM algorithm, the safety factor jges = 1.4 and static capacity of the tank wall ask = 19.7% were calculated.

Open access
Assessment of Dimensions in Order to Aid Classification of European Red Mite and Two-Spotted Spider Mite by Means of Digital Imaging of Infected Leaves

Abstract

The methods currently used to assess orchard infestation are time-consuming and do not take into account non-adult forms of mites, due to their small size. Advance in digital imaging technology, however, has resulted in the discovery of a more viable method to enable a fast and reliable assessment of orchard infestation. Digital images of infected apple leaves were made and examined for the presence of European red mites and two-spotted spider mites. As well as adult mites, non-adult European red mite forms were also encountered. After extracting all objects considered as mites from the image, imaging software was then used to assess their dimension and shape parameters. Length, width, area, and equivalent diameter were different for all three observed mite groups: adult female European red mites, possible non-adult European red mites and adult two-spotted spider mites. Differences in circularity and elongation were found in adult two-spotted spider mites and various forms of European red mites, while the perimeter was similar in adult European red mites and two-spotted spider mites, and different in the non-adult forms of European red mites. However, as the ranges of 95% prediction intervals for these features overlap, a combination of at least two features as well as employing statistical procedures may greatly increase the probability of appropriate classification of the observed objects as different mites.

Open access