Wyniki wyszukiwania - BazTech

1

The influence of different steering systems on a wheel slip

Stajnko D., Berk P., Mursec B., Vindis P.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 55, nr 2

817--824

EN

Purpose: Modern and advanced mountain tractor allows four different modes of steering wheels: front wheels, back wheels, four wheels and crab steering. The current paper presents the impact of different ways of steering to control the slip in the work transverse on the steep hill slope (39.08%). Design/methodology/approach: For each mode of steering eight measurements were made; four measurements at a forecasted speed of 0.69 m/s and four measurements at a speed of 1.39 m/s. During the two of four measurements the travelling direction was from the left to the right, and vice versa. Findings: The measured slip depended significantly on the steering system, while the driving direction did not cause any differences in the slip. Research limitations/implications: The experiment results presented herein can be applied only with the similar mountain tractors, which allows four different modes of steering wheels. Additional limitation represents the working polygon and the growing conditions of grass. Practical implications: The crab - steering resulted in the smallest slip (5.96%) at the average driving speed of 1.08 m/s. When steering with all four wheels, the slip at the average speed of 1.03 m/s increased to 7.27%. The biggest slip was measured when steering with only front wheels was applied. In this case the slip was 8.07% at the average speed of 1.01 m/s. Originality/value: The findings from our experiments indicated that it is very useful to have all wheels steering tractor when working on step slope, because it is grass friendly, offers bigger agility of tractor and improve the safety of the operator.

2

Synthesis water level control by fuzzy logic

Berk P., Stajnko D., Vindis P., Mursec B., Lakota M.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 45, nr 2

204--210

EN

Purpose: This paper focuses on evolving of two types fuzzy and classical PID liquid level controller and examining whether they are better able to handle modelling uncertainties. A two stage strategy is employed to design the synthesis fuzzy and classical PID controller with the process of the first and second order and implements disorder (quadratic function). Design/methodology/approach: The synthesis of fuzzy and classical PID liquid level controller was realized with the HP laptop 6830s Compaq NA779ES, software Matlab/Simulink 2008b, FIS (Fuzzy Inference System) soft logical tool, input-output unit 500 Dragon Rider and ultrasonic sensor. Using the simulation program Matlab/Simulink/FIS we simulate the operation of fuzzy and classical controller in the liquid level regulating cycle and made a comparison between fuzzy and classical controller functioning. Findings: From the responses to step fuzzy and classical controller for first-order process shows that the actual value of the controlled variable takes the value one. Fuzzy and classical PID controller does not allow control derogation, which is also inappropriate for fuzzy and classical control cycle with incorporating disturbance. Classical PID controller in the first-order process provides short-term regulation, such as fuzzy PID controller. In fuzzy control cycle with fuzzy PID controller and incorporating disturbance in the process of second-order the control cycle is stable and at certain predetermined parameters (integral gain) a control does not allow deviations. Research limitations/implications: In future research, the robustness of the fuzzy logic controller will be investigated in more details. Practical implications: Using fuzzy liquid level controller can reduce power consumption by 25%. Originality/value: Fuzzy logic controller is useful in applications of nonlinear static characteristic, where classical methods with usually classical PID controllers cannot be a satisfactory outcome.

3

The efficiency of different machines for controlling of western corn rootworm adults

Stajnko D., Janzekovic M., Mursec B., Vindis P., Cus F.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 40, nr 1

79-86

EN

Purpose: the appearance western corn rootworm (Diabrotica virgifera virgifera LeConte) in Slovenia brings new challenges to machines used for pesticide spraying of corn. The control of western corn rootworm is difficult due to the height of the corn crop in July-August. The current paper presents the exploitation characteristics of mistblower with cannon and field sprayer with high-mounted spraying boom and vertical tube extension with distributing nozzles on pesticide distribution over the corn plant. Design/methodology/approach: Two field experiments with different air adjustments and driving speed (mistblower with cannon) and nozzle flow and driving speed (field sprayer with high-mounted spraying boom) were research. Findings: The ventilator of the mistblower spread the pesticide over the wider band of the field as the field sprayer, however the pesticide distribution measured as coefficient of variation did not fulfil the legislative requirements. Research limitations/implications: The experiment results presented herein can be applied under similar equipment adjustment, working speed and growing conditions of the corn plant (78.000/ ha and the height of 2.70 m). Practical implications: The field sprayer with high-mounted spraying boom and vertical tube extension was proved as an efficient machine for controlling of western corn rootworm adults in the developed corn growing over 2.70 m. With the presented technical procedure the damage caused by the western corn rootworm can be almost completely prevented. However due to the growing stage of the plant in the time of spreading of the adult, about 6.5 % of the plants are overridden. Originality/value: By implementing the findings from our experiments a severe damage in corn yield caused by the western corn rootworm can be reduced significantly. On that way an effective way in production of corn can be contribute to farmers’ economy.

4

The art equipment for measuring the horse’s heart rate

Janzekovic M., Prisenk J., Mursec B., Vindis P., Stajnko D., Cus F.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 41, nr 1-2

180-186

EN

Purpose: of this paper: Heart rate is a reliable indicator of the stress. Non-invasive methods have advantage over the methods that have a negative influence on the condition of an animal. When breeding sport horses, which undergo stressful training every day, it is required, from an ethical aspect, to monitor their capabilities by using most advanced electronic devices Polar Sport Tester and Polar Equine RS800cx G3. Design/methodology/approach: The original Polar ProTrainer 5 Equine edition software facilitates the analysis of individual training phases and gives the number of heart beats, average heart rate, average speed and distance covered in individual training phases. Findings: Heart rate increased, in warming up phase, from the value associated with a resting horse (30 to 40 bpm) approximately in one minute, while, during the slow cooling down phase, ten minutes were required for the heart rate to reach the afore-mentioned value. During quick trotting heart rate are 112 heart beats per minute, while during steeplechase phase, it increased to the value of 160 to 170 heart beats per minute. Research limitations/implications: To receive heart rate without disturbances already we moisten the skin on the contact spots, using a mixture of water and electrolytes (Salvana Nutrilyt). Placing receiver on the saddle close by the T56H transmitter was the optimal choice. Practical implications: Modern equipment makes monitoring the horse’s heart rate accurately and to perform, safely and without disturbances, exercises required during training. It also checks the heart rate, which indicates the horse’s health. Originality/value: Polar Sport Tester and Polar Equine RS800cx G3 are state of the art products that facilitate the receipt of the horse’s heart rate signals. The accuracy of the acquired results can be compared with those obtained with ECG measurements.

5

Anaerobic digestion of maize hybrids for methane production

Vindis P., Mursec B., Janzekovic M., Stajnko D., Cus F.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 40, nr 1

87-94

EN

Purpose: This research project was aimed at optimising anaerobic digestion of maize and find out which maturity class of corn and which hybrid of a particular maturity class produces the highest rate of biogas and biomethane. Also the chemical composition of gases was studied. Design/methodology/approach: Biogas and biomethane production and composition in mesophilic (35 degrees C) conditions were measured and compared. The corn hybrids of FAO 300 - FAO 600 maturity class were tested. Experiments took place in the lab, for 35 days within four series of experiments with four repetitions according to the method DIN 38 414. Findings: Results show that the highest maturity classes of corn (FAO 500) increases the amount of biogas and biomethane. The greatest gain of biogas, biomethane according to maturity class is found with hybrids of FAO 400 and FAO 500 maturity class. Among the corn hybrids of maturity class FAO 300 - FAO 400, the hybrid PR38F70 gives the greatest production of biogas and biomethane. Among the hybrids of maturity class FAO 400 - FAO 500, the greatest amount of biogas and biomethane was produced by the hybrid PIXXIA (FAO 420). Among the hybrids of maturity class FAO 500 - FAO 600 the hybrid CODISTAR (FAO 500) the highest production of biomethane. Production of biomethane, which has the main role in the production of biogas varied with corn hybrids from 50-60 % of the whole amount of produced gas. Research limitations/implications: Economic efficiency of anaerobic digestion depends on the optimum methane production and optimum anaerobic digestion process. Practical implications: The results reached serve to plan the electricity production in the biogas production plant and to achieve the highest biomethane yield per hectare of maize hybrid. Originality/value: Late ripening varieties (FAO ca. 600) make better use of their potential to produce biomass than medium or early ripening varieties.

6

The effect of direct seeding on the soil resistance and the silage corn yield

Stajnko D., Janzekovic M., Brus M., Cus F.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 35, nr 2

184-190

EN

Purpose: The paper compares the effect of five different direct seeding methods to the conventional tillage on the emerging and yield of silage corn (Zea may L.) in two different pedo-ecological conditions of Slovenia. Design/methodology/approach: A randomly selected 4x6 block designed field test was carried out; gliphosat treatment 1 week before seeding (V1), mowing+focus ultra on the whole plot 3 weeks later (V2), mowing+focus ultra in bands 3 weeks later (V3), mowing+focus ultra in bands 3 weeks later+mowing the inter-row after emergence (V4), conventional tillage (V5), focus ultra on the whole plot 3 weeks after seeding (V6). Findings: The highest emergence was on parcels with treatment V5; 98.99 % in Noršinci and 82.75 % in Pohorski dvor. The (V1) treatment influenced lowest emergence in Noršinci (82.48 %) and Pohorski dvor (63.25 %). The number of emerged seedlings affected the highest yield of fresh silage on V5 (50.590 kg ha-1 - Nošinci and 45.661 kg ha-1 - Pohorski dvor) and dry matter (20.228 kg/ha). However, there was no difference to V1 and V4. The penetrometer measurements showed the highest soil resistance (119.78 N cm-2) in Noršinci on V3 and (185.31 N cm-2) in Pohorski dvor on V4. Research limitations/implications: The experiment presented herein can be applied under similar pedo-climatical condition. Practical implications: Alternative seeding methods can reduce the fuel consumption and CO2 emission by decreasing the number of passes on the field. Originality/value: By implementing the findings from our experiments a high intensity of soil engagement and inversion of the soil by using of mouldboard plough can be omitted on the majority of sandy and silty-loam soils. On that way the energy saving-method can make an effective contribution to farmers’ economy.

7

Mastitis detection based on electric conductivity of milk

Janzekovic M., Brus M., Mursec B., Vinis P., Stajnko D., Cus F.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 34, nr 1

39-46

EN

Purpose: If measurements of the increased total count of somatic cells in the individual udder quarter or in the whole udder could be determined with electric conductivity by means of the microprocessor-controlled device Mastitron LF 3000 enough precisely to predict the presence of subclinical mastitis. Design/methodology/approach: The occurrence of increased count of somatic cells in milk was found out group by group by the method of measuring the electric conductivity of milk. For the milk conductivity the average measurement from all four udder quarters was taken into account. The population of 102 lactating cows (Black and white, Simmental and Brown Swiss breed) on seven farms fore three summer months was observed. Findings: It was established that higher average electric conductivity than 6.5 mS/cm confirmed in 80% also the increased count of somatic cells in milk. When evaluating the differences between the quarters exceeding 1 mS/cm also a higher total count of somatic cells was confirmed in 73.7%. Moreover, statistically significant relation (P<0.01) between the CMT test and the ECM was found out so it can be claimed that the two methods do not exclude themselves mutually. Research limitations/implications: It was found that the reliability of the ECM in our case was 80% depending to a large extent on the milk composition which changed depending on the stage of lactation, type of feed and general health condition of animals. For a more reliable, accurate and faster implementation of the ECM method further researches will be necessary. Practical implications: Though the ECM method of determination of the subclinical mastitis of the milch-cows is well established in the world, it is not yet known well enough in the Slovene practice as a method of diagnosing the subclinical mastitis. Originality/value: It was found that the results of our research in production circumstances were comparable with the indications of the maker and foreign researchers.