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Analysis of Performance of Short Tree Logging with Farm Tractor and Logging Trailer

Abstract

The paper presents analysis of efficiency of the logging unit comprising Belarus 820 farm tractor and PD80 logging trailer equipped with Ryś-1 crane. Analysis was made based on the working day timing. The unit logged 1- meter long tree pieces (hornbeam, oak, birch) from the area where material for logging was distributed irregularly on the entire felling site. Unfavourable atmospheric conditions were reported during the working day (a thick layer of snow, low temperature, not frozen soil) which could have influenced the unit operation performance. Despite that the performance of the logging unit was comparable to similar logging units described in the literature. Determined coefficient of use of the operating time of the machine K02 was 0.93, coefficient of use of the shift working time K04 − 0.9, coefficient of use of the shift exploitation time K07 − 0.8. Hourly performance in the shift exploitation time was 4.98 m3·h−1, efficiency in the shift working time W02 − 4.80 m3·h−1 and performance in the general shift time W07 − 4.30 m3·h−1.

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Comparative Study on the Applicability of Analytical and Experimental Methods in the Analysis of the Safe Use of Rail Tankers Carrying Petroleum Products Under Pressure

Abstract

The safety of railways has been and remains a critical topic. Whether it is infrastructure or rolling stock, the issue of safety is a permanent concern of the utmost importance, being reflected in the efficiency of any transport system.

This paper focuses on the safety in operation of pressure vessels that equip railway tanks. There are many articles and works on this subject, and it is well-known that there are both national and international regulations regarding their design, execution, operation and maintenance. Also, there are quite a few reports on the BLEVE (Boiling Liquid Expanding Vapour Explosion) phenomenon resulting in material damage and significant casualties. The BLEVE-type explosion is not considered a chemical explosion derived from a gas-air explosive environment (also present in non-flammable gases), but rather a mechanical explosion through over-pressurization.

Thus, we propose a comparative study between the results obtained using theoretical methods and those obtained as a result of tensoresistive measurements on such a tanker.

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Development of New Technologies for Cattle Breeding Systems Taking Into Account Sustainable Environmental Conditions

Abstract

Properly designed housing buildings, with regard to reduction of a negative influence on environment, are necessary for ensuring sustainable development in agriculture. The objective of this paper was to show the results of environmental conditions research on high milk yield dairy cattle in different housing systems. Temperature and relative humidity of air and concentrations of harmful gases − ammonia and carbon dioxide accompanying them were investigated.

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The Effect of Ecological and Geographical Factors on Environmental Parameters as a Background for Vegetables Selection

Abstract

The aim of the study is to find out the role of the ecological and geographical fator in obtaining sustainable yields and the assessment of the environment as a background for the selection in breeding of vegetable adaptive ability. Objects of research: winter garlic, vegetables beans, headed salad. Research was conducted in various ecological and geographical zones of Belarus, Russia, Uzbekistan. Environmental parameters as the background for selection were determined using Kilchevsky’s, L. V. Hotyleva’s (1985), technique, Kilchevsky (1985). Differences between testing points on environmental parameters for determining the trait “yielding capacity” have been revealed, maximum environmental productivity at assessing various genotype sets has been determined. Long-term research showed that sustainable productivity depends on the ability of a genotype to respond to environmental conditions. Based on the obtained results, statistical parameters of quantity traits of the parent material, their variability depending on ecological-geographical factor and the character of influence on the potential yields and ecological sustainability have been received. Using various ecological and geographical zones helps to reveal the potential of plants in given conditions on sustainability and productivity parameters. Testing of winter garlic, beans, head salad allowed differentiation of them according to adaptability capacity at various set of genotypes. It was found out that research must be carried out at highly productive and analyzing backgrounds to get the required material. One of the main methods enabling to increase plant selection efficiency is the use of natural ecological backgrounds.

Open access
Impact of Caustic Soda Solution Temperature on Efficiency of its Cleaning on Solid Sediments After Completed Process of Cleaning in CIP System of Brewing Unit

Abstract

The paper presents the results of analysis concerning the impact of temperature on sedimentation in the caustic soda solution that constitute a contamination after the process of cleaning utensils and pipes for hopped wort transport in the brewery. The solution was collected from the production plant after the process of cleaning and subjected to 12-hour sedimentation and changes of the solid particles participation, their size and percentage share in the solution was determined. The study was carried out with the Shadow Sizing method. The results were subjected to statistical analysis and the surface area of the response of the relation between the time and temperature of sedimentation and the number of particles which stay in the solution was calculated. The research results proved that the temperature significantly affects the cleaning degree of solutions by sedimentation and its duration. After sedimentation in solutions, particles with the surface area from 0.001-0.003 mm2 remain. Those particles are not subject to sedimentation and constitute a coloidal suspension in the solution.

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The Impact of Shearing and Flexibility of Cultivator Tines on the Vertical Forces Value

Abstract

The paper presents the outcomes of the research on the impact of shearing depth and flexibility of cultivator tines with cultivator points on the value of vertical forces acting thereon. The object of the research consisted in “S” tines with the flexibility coefficient of 0.0061; 0.0711; 0.0953 and 0.1406 m∙kN−1. The investigations were carried out in field conditions in sandy clay soil with moisture of 11.2%. The forces were measured for the assumed shearing depths which were 5, 9 and 13 cm at the shearing speed of 3 m∙s−1. A stand for measurement of forces acting on soil shearing tools in the field conditions was used. It was found out that the increase of the shearing depth causes a linear increase of the vertical force, but the force gradient decreases with the growth of the tine flexibility. Moreover, it was found out that the increase of the tine flexibility at the beginning causes the increase and then the decrease of the vertical force regardless the shearing depth. The impact of flexibility on the vertical force value was described with the parabola equation. The tines flexibility, at which the highest value of vertical force may be expected, grows with the reduction of the shearing depth.

Open access
Optimization of the Synergies Between Preparation of High-Speed Railway Train Running Diagram and Station Route Allocation Plan

Abstract

Introduction. Station route allocation plan is an important extension of the train running diagram and the both are closely intertwined so the overall research on the synergetic preparation method is more beneficial in improving the preparation quality of the train running diagram and providing better service for passengers. Therefore, the research topic has practical significance.

Methodology. Based on extensive literatures, this paper studies the synergetic preparation method of train running diagram and station route allocation plan in detail and analyses their association for providing a theoretical basis for the synergetic preparation method.

Results. This work introduces the synergetic, analyses the systematic characteristics of the operation organization system of high speed railway and puts forward the optimization strategy of train running diagram and station route allocation plan.

Conclusions. The work provides the solution for the preparation of the train running diagram and station route allocation plan by solving the examples based on the relevant optimization factors, such as train running in districts and train arrangement.

Open access
Pedestrianism as an Effective Tool for Sustainable Intra-City Commuting in Calabar, Southern Nigeria

Abstract

The promotion of walking has become a global strategy in sustainable urban transportation planning. This is with the aim of reducing the urban commuter’s problems that result from the dominance of motorized urban transit, especially in developing countries with an increasing rate of urbanization. This study is carried out in Calabar, Southern Nigeria with the aim of assessing the conditions under which pedestrianism is enhanced. Research questionnaires were administered to household heads in all 22 localities with political delineation (wards) in the city. Respondents were sampled using the stratified sampling technique where every 10th residential house is sampled after the initial listing of houses. Logistic regression analysis was conducted to predict the conditions under which about 382 household heads (about 98% respondent rate) in Calabar could undertake utilitarian walking using factors such as motorized traffic, weather conditions, lack of safety of pedestrians and socio-economic variables as category predictors. A test of the full model against a constant single model was statistically significant, indicating that the predictors, as a set, reliably distinguished utilitarian walking and non-walking (chi square = 60.544, p < .001 with df = 17). Nagelkerke’s R2 of .232 indicated a moderately strong relationship between prediction and grouping. Prediction success overall was 70.5% (53.5% for non-walking, and 81.5% for walking). The Wald criterion demonstrated that only pedestrian conflict, lack of safety of pedestrian and the age of the pedestrian made a significant contribution to the prediction in model 1 (p = .000). Furthermore, about 99.2% of pedestrians indicated walking distances of not more than 5km while on the other hand, they can afford 0.8km to bus station, 3km to school, 5km for shopping, and about 20km for recreation trips. The study recommended counseling strategies for promoting pedestrianism among which is the development of pedestrian walkways and complementary facilities to enhance pedestrian safety and comfort.

Open access
Performance Evaluation of a Developed Cashew Nut Shell Liquid Expeller

Abstract

The thick vesicant oil liquid contained in the shell of cashew nut, called cashew nut shell liquid (CNSL), has been known for its innumerable applications in chemical industries. Performance evaluation of a newly developed CNSL expeller was carried out to determine the effect of moisture content and pressing duration on extraction parameters. The nut shells were grouped as A: 14.00-16.99%, B: 17.00-19.99% and C: 20.00-22.99% (w.b.) moisture content at 2, 4, 6, 8 and 10 minutes pressing time and combination of 1, 2, 3, 4 and 5 kg of cashew nut shells. Analysis of variance (ANOVA) was used for the stastical analysis. The best mass of liquid extracted, best extraction efficiency and best percentage oil recovery occured at pressing duration of 10 minutes and moisture content of 14.00-16.99% (w.b.), while the best machine capacity was at pressing duration of 2 minutes and moisture content of 14.00-16.99% (w.b.). Results showed that the effects of the pressing duration and moisture content on mass of liquid extracted, machine capacity, extraction efficiency and percentage liquid recovery were significant at 0.05. Meanwhile, the effects of the pressing duration and moisture contents were not significant for the feed rate. Increase in the pressing duration at decreasingthe moisture content resulted in the increase in the mass of liquid extracted, extraction efficiency and percentage liquid recovery while increase in pressing duration and moisture content resulted in decrease in machine capacity of the expeller.

Open access
Process Efficiency and Energy Consumption During the Extrusion of Potato and Multigrain Formulations

Abstract

The aim of the research was to determine the effect of extrusion conditions (various moisture content of raw materials and screw rotation speed), as well as the effect of recipe composition on the process efficiency and the energy consumption during treatment of potato and multigrain products. The efficiency of the extrusion process (Q) was determined by the mass of the product obtained at a given time for all prepared raw material mixtures and the process parameters used, while the specific mechanical energy demand was determined using the SME index. The obtained results allow to conclude that the level of raw materials moisture content had a greater impact on the efficiency and energy consumption of the extrusion process than the variable screw speed during the treatment. The efficiency of the process increased with the increasing moisture of the tested compositions, while a decrease in the requirements of SME was observed. The use of differentiated raw material compositions also influenced the Q and SME values determined during the tests.

Open access