Research in Agricultural Engineering, 2017 (vol. 63), issue 2
The use of stereophotogrammetry to determine the size and spatial coordinates to generate a 3D model of an animalOriginal Paper
Ladislav Libich, Michal Hruška, Petr Vaculík, Miroslav Přikryl
Res. Agr. Eng., 2017, 63(2):47-53 | DOI: 10.17221/65/2015-RAE 
This study considers the process of 3D scanning of farm animals using the method of stereophotogrammetry. This involves taking stereoscopic pictures of an animal, from which the spatial coordinates of selected anatomic points on the animal are determined using triangulation. These points are chosen in such a way to make it possible to determine from them the dimensions used in animal breeding databases and to draw a skeleton to be used in generating a 3D model of the animal. The dimensions of the animals were identified from this test group using an analysis of stereoscopic images and these were then compared with measurements done by hand on the same...
Evaluation of efficiency of technologies for wastewater sludge hygienisationOriginal Paper
Petr Junga, Pavel Mach, Jan Mareček
Res. Agr. Eng., 2017, 63(2):54-61 | DOI: 10.17221/10/2016-RAE
The paper compares the methods of hygienisation of wastewater treatment plants sludges with respect to meet legislative requirements of conditions for using the treated sludge on agricultural land. The paper draws a comparison of the experimental results between the method of hygienisation and stabilisation of the sludge through the autothermic aerobic thermophilic stabilisation (AATS) by pure oxygen and the method of sludge hygienisation by pasteurization. Results of the experiment confirm that sewage sludge treated by both assessed hygienisation technologies meets legislation requirements for application to agricultural soil.
Manure leachate production and change in manure weight during the storage depending on the amount of beddingOriginal Paper
Jiří Vegricht, Josef Šimon, Jiří Bradna
Res. Agr. Eng., 2017, 63(2):62-70 | DOI: 10.17221/7/2016-RAE
In the experiment, a group of 10 dairy cows was housed in a pen bedded with various amounts of wheat straw (5.2-13 kg/cow per day). The resulting mixture of feces, urine and bedding was stored in cubic containers with a volume of 1.5 m3. At regular intervals, the containers containing manure were weighed and manure leachate production was assessed. Daily changes in individual monitored variables over time in accordance with the amount of bedding per livestock unit per day (1 livestock unit = 500 kg live weight) were modelled using nonlinear mixed regression models. It was determined that manure weight changes and daily production of manure...
Moisture content modelling of thermal properties of persimmon (cv. 'Kaki')Original Paper
Somaye Akbari, Reza Amiri Chayjan
Res. Agr. Eng., 2017, 63(2):71-78 | DOI: 10.17221/3/2016-RAE
Persimmon is one of the tasty and sweet fruits with short shelf life. Thermal conductivity, thermal diffusivity and specific heat are necessary for storage, drying, packaging and designing of distillation machines. In this research, thermal conductivity and thermal diffusivity of persimmon were calculated using the line-heat source probe and Dickerson method. The experiments were conducted at four temperature levels of 40, 50, 60 and 70°C, and four moisture content levels of 37.77, 56.49, 70.47 and 88.42 (%, w.b). Results showed that the thermal conductivity of persimmon was improved by increasing temperature and moisture content of the samples. The...
Thermal properties of soursop seeds and kernelsOriginal Paper
Oloyede Christopher Tunji, Akande Fatai Bukola, Oriola Kazeem Olaniyi, Oniya Oluwole Oluwatoyin
Res. Agr. Eng., 2017, 63(2):79-85 | DOI: 10.17221/22/2016-RAE
The thermal properties of soursop seeds and kernels were determined as a function of moisture content, ranged from 8.0 to 32.5% (d.b.). Three primary thermal properties: specific heat capacity, thermal conductivity and thermal diffusivity were determined using Dual-Needle SH-1 sensors in KD2-PRO thermal analyser. The obtained results shown that specific heat capacity of seeds and kernels increased linearly from 768 to 2,131 J/kg/K and from 1,137 to 1,438 J/kg/K, respectively. Seed thermal conductivity increased linearly from 0.075 to 0.550 W/m/K while it increased polynomially from 0.153 to 0.245 W/m/K for kernel. Thermal diffusivity of both seeds...
Content of microorganisms in cereal straw
Jiří Souček
Res. Agr. Eng., 2017, 63(2):86-90 | DOI: 10.17221/9/2016-RAE
Straw is an important agricultural raw material with application in agriculture, energy sector and other fields of activity. A major impact on reduction of the straw quality is that of an excessive content of microbiological agents caused by improper storage. By simulation of different conditions of storage the development of microorganisms (moulds and yeasts) was determined in the straw of wheat under different water content. Total content of microorganisms varied in a wide range from 103 up to 105 CFU/g. The excessive amount of these microorganisms results not only in a reduction in the quality of raw material due to the development...
Abrasive wear resistance of selected woodsOriginal Paper
Milan Brožek
Res. Agr. Eng., 2017, 63(2):91-97 | DOI: 10.17221/74/2015-RAE
In this contribution, the results of the wear resistance study of 10 sorts of wood (apple, aspen, beech, hornbeam, horse-chestnut, London plane, mahogany, silver fir, sour cherry and sweet cherry) are published. The laboratory tests were carried out using the pin-on-disk machine when the abrasive clothes of three different grits (240, 120 and 60) were used. The wear intensity was assessed by the volume, weight and length losses of the tested samples. From the results of the carried out tests it follows that the wear resistance of different woods is different. It was proved that the wear resistance of different woods depends on the abrasive particles...