INMATEH - Agricultural Engineering

6

Authors: Nedelcu A., Ciuperca R., Popa L, Voicu E., Zaica A.

Solar radiation is a natural heat source with multiple uses on farms, for example, heating the air used in drying fruit technology and for domestic hot water or artificial drying of forage crops in order to obtain the hay. The paper presents the results of researches performed with a plane solar collector particular type, which is made of common materials and is designed to heat the air within special fodder ventilating installations for obtaining high quality hay and reducing conventional energy consumption. During this research, it has been measured and continuously monitored the following parameters: meteorological parameters (solar radiation, temperature, humidity), the temperature in the panel at various times of the day, TPS, air velocity in the panel, VPS, temperature variation during the panel ventilation,  T solar collector efficiency, η.

6

Authors: Safta V.V., Dilea M., Constantin G.A.

This paper presents the algorithm used to perform computations related to processing of results obtained in laboratory experiments for determining the characteristic parameters of filtering process in incompressible layer of granular material in a quick and convenient way.

8

Authors: Sorică E., Pirnă I., Sorică C., David L.

The paper presents the kinematic analysis of mechanism which drives the eccentric separator comprised by the technical equipment of harvesting Miscanthus rhizomes, where the positions, speed and accelerations of component elements, are determined. The kinematic analysis of the mechanism which drives the eccentric separator allows to identify the functional and constructive parameters which have to be operated for improving the mechanism structure and performance.

8

Authors: Căsăndroiu T., Buciuman F.V.

The thesis presents the main theoretical elements related to the air flow going through granular bed under vibrating motion. It draws the hypothesis of analogy between the vibrating granular layer and the stationary layer, having in view that the seeds speed on the machine table are relatively low and consequently their influence upon air flow through layer can be neglected. It is emphasized that in this case can be utilized with good results, the Ergun equation as a link between pressure downfall (-ΔP) on the thickness of the seed layer and air speed for a global laminar turbulent way through layer. On this basis have been presented theoretical studies for two different machines used in the concrete work practice for wheat and barley seeds. Experimental results obtained regarding the pressure downfall (-ΔP) subject to the fans air flow of these machines have been compared to those evaluated by calculation and there is reasonable difference (errors ±5%).

8

Authors: Matache M., Persu I., Voicu Gh., Manea I., Biriş S.Şt.

In the paper there are presented experimental researches regarding testing in simulated and accelerated regime of bogie frame type resistance structures. Starting from the loads at which the structure is exposed in daily exploitation , there was developed a testing programme in simulated and accelerated regime in order to verify its structural integrity and estimate its span of.

10

Authors: Sfîru R., Constantin N., Ludig M., Cârdei P., Muraru V.

This study comprises two structural analyses applications, having as subject the same structure, very common for agricultural machinery designed to tillage, namely a beam, [5], [7]. The two applications are made in well known CAD1 programs, each including its own structural analysis module: SolidWorks and Autodesk Inventor. The study aims to demonstrate the easiness with which the analysis is performed in either of the two programs, but especially, the way in which the results of the two analyses converge. The converged results are able to show, that the use of one or other of the programs is irrelevant, of course, in terms of the analysis modules, that both programs have. In this study it compares the performances in terms of linear static analysis (check the resistance) and the modal analysis (analysis in frequencies or calculating of a number of structure natural frequencies). It can be said that, the results obtained without doing an additional study of convergence and stability on meshing are satisfactory, possibly good enough in the case of the maximum equivalent stress in the structure.

10

Authors: Peng Zhang, Jian Song, Shenglei Gong, Bo Jiang, Muham, D. Polar

Eggplant picking robot is a type of complex optical-mechanical-electrical equipment in greenhouse environment. Its structure and control are more exigent than traditional industrial robot. Optimization design method was utilized for the design of the eggplant picking robot body structure parameters in accordance with the eggplant growth and distribution space. In order to determine the spatial position relationship between the eggplant picking robot components and the end effector, the theoretical model of robot was established by virtue of Denavit-Hartenberg approach and the positive solution of the kinematic equation is obtained. Premultiplication decoupling of and matrix were adopted to solve inverse kinematic solution with the help of Matlab software. Pro/E software was used to establish 3-D simulation model, and ADAMS (Automatic Dynamic Analysis of Mechanical Systems) simulation software was imported for the kinematics simulation analysis. It was indicated by the simulation results that the kinematic model established by D-H approach reflects the real motion conditions of the robot, and both the positive and inverse kinematic solutions are correct. Structure of four degrees freedom eggplant picking robot was reasonable, it could meet the requirements of eggplant picking in the greenhouse cultivation pattern.

10

Authors: Żelaziński T., Ekielski A., Zdanowska P., Florczak I.

This study attempted to understand the influence of ultrasound pretreatment on quality of extrudates. The maize and buckwheat seeds were subjected to low power ultrasound at 40kHz frequency. The pretreated material was processed using extrusion cooking technology. The effect of the ultrasound waves on quality of extrudates produced from pretreated seeds and its grinds were investigated. Typical quality standard parameters like sectional expansion, volumetric expansion indices, water solubility index and water absorption index of extrudates were investigated by using central composition design. For all extrudates samples inner cells structure was also determined. The inner texture of extrudate as structure and configuration of pores were described using mean size of pores, their number on cross section unit, geometric orientation of pores. The extrudates produced from pretreatment materials were compared with extrudates obtained from non-treated material. Extrudates made from pretreated material showed different texture properties than produced from ultrasound untreated ones.

12

Authors: Feng Y., Zhou J., Wang Z., Zhang W., Yu.D.

At present, irrigation in Ziziphus Jujuba orchards around Tarim basin in Xinjiang Province, China, is mainly surface irrigation. Due to outdated irrigation technology and low irrigation efficiency, the fruit yields are low, which seriously affects sound development of local special forest fruit industry in Xinjiang. Infiltrating irrigation technology has favorable water-saving effects and studying its impact on the physiological and yield variation of Jujube trees would therefore greatly assist the development of the Jujube industry in Xinjiang China. Several ten-year-old Jujube trees were selected in Akesu area of Xinjiang to investigate the effects of different water-saving irrigation methods on their physiology and yield. Diurnal variation of photosynthetic capacity in Jujube leaves during florescence, young fruit and fruit expanding stages and Jujube yield were measured under 6000 m3/ha of alternate partial root-zone irrigation and conventional infiltrating irrigation. The results indicated that: (1) the diurnal variation of net photosynthetic rate in Jujube leaves presented a bimodal curve with a midday depression phenomenon. The diurnal variation of transpiration rate appeared to single peak type. The diurnal variation of water use efficiency was a single-valley curve. The stomatal conductance varied during the growth season; (2) under conventional irrigation, the net photosynthesis rate, stomatal conductance and transpiration rate increased with increased irrigation volume; and (3) with the same irrigation volume, the root-divided alternative irrigation, compared with conventional irrigation, reduced leaf transpiration rate and increased leaf net photosynthesis rate and water use efficiency, resulting in an increase of Jujube yield by 11% per hectare. The study showed that root-divided alternative irrigation could save water consumption and increase Jujube yield

14

Authors: Tao Tian, Xiaochun Xu, Pengling Liu, Chung-chia Lee

Rural informatization is an inevitable requirement of agricultural development. In the paper a two-phase model with DEA-Tobit was adopted to analyze the developmental efficiency and the influencing factors of rural informatization in China during 2007-2010. The results showed that, on the whole, the overall developmental efficiency of rural informatization in the Middle and Northwest China was lower than that in other regions of China. In addition, the decisive influencing factors on developmental efficiency of rural informatization were resulted from the nation’s macro policy and the global construction of rural informatization projects. The level difference in regional economic development was the main reason for the variation in developmental efficiency. Moreover, the structure and level of consumption by rural residents was an important source that had affected the developmental efficiency. Furthermore, the age of rural population and the education level had a significant influence on the developmental efficiency of rural informatization