Grass silage thickening technology using centrifugal undirected action vibrator

A vibratory device to thicken silage was designed and tested, experimental research was carried out using the device for thickening chopped mass of red clover and maize. Dependences of grass mass density variation on duration of thickening by the device and dependences of relative grass pressure on vibration frequency have been examined and assessed. The research has showed that during vibratory thickening grass layer thickens intensively for 5-10 min and this vibrator is advisable for thickening grass layers of 0.5-0.6 m thickness. After investigation of dependence of grass thickening and grass comparative pressure on vibration frequency it was established that most effectively vibrator works at 43.96 s-1 frequency. Consequently, it is reasonable to thicken grass using undirected action vibrator at the mentioned frequency or close to it. Experimental research has established that red clover density of 350 kg/m3 can be achieved by centrifugal-undirected action vibrator. That is insufficient density for grass silage. This vibrator is much more efficient for maize thickening when nearly double mass density is achieved. Therefore, this type of vibrator is advisable for thickening of big stems plants such as maize and its mixture with red clover. It was established, that thickening of maize – Caucasian goat’s rue (Galega orientalis Lam.) mix (2:1 ratio) by undirected action vibrator – after 20 min of thickening (2×60 kg) gave 425 kg/m3 and 124 kg/m3 of dry matter density respectively. It is not sufficient density for grass thickening. Such vibrator is much more efficient in thickening maize, it reaches bigger mass density – 730 kg/m3 and 223 kg/m3 of dry matter. On the grounds of the research results it can be stated that the vibratory thickener of investigated design (undirected action vibrator) is reasonable to use in thickening maize and maize-red clover mixture. This vibrator is not suitable for thickening of red clover, Caucasian goat’s rue and maize-Caucasian goat’s rue mixtur

Boundary Element Modeling of Acoustic Fields Generated During Ultrasonic Angioplasty

We investigated possibilities of application of boundary element method (BEM) to modelling of acoustic fields generated during ultrasonic angioplasty. It was shown that modelling by means of BEM can be more efficient comparing with traditionally used modelling by means of finite element method (FEM). We also considered test problem of calculation of acoustic field created by ultrasonic waveguide in semi-infinite fluid media and the problem was solved by means of BEM and FEM with comparative analysis of obtained results. Modelling by means of BEM additionally involves application of mirror source method for avoidance of treatment of infinite fluid boundary. On the basis of analysis of the test problem we shown that BEM can be used as efficient tool for modelling of acoustic fields generated during ultrasonic surgical procedures, particularly, during ultrasonic angioplasty. BEM has several advantages in comparison with FEM and can be used as alternative to traditionally used modelling by means of FEM or as supplementary method

Grass silage thickening technology using centrifugal undirected action vibrator

A vibratory device to thicken silage was designed and tested, experimental research was carried out using the device for thickening chopped mass of red clover and maize. Dependences of grass mass density variation on duration of thickening by the device and dependences of relative grass pressure on vibration frequency have been examined and assessed. The research has showed that during vibratory thickening grass layer thickens intensively for 5-10 min and this vibrator is advisable for thickening grass layers of 0.5-0.6 m thickness. After investigation of dependence of grass thickening and grass comparative pressure on vibration frequency it was established that most effectively vibrator works at 43.96 s-1 frequency. Consequently, it is reasonable to thicken grass using undirected action vibrator at the mentioned frequency or close to it. Experimental research has established that red clover density of 350 kg/m3 can be achieved by centrifugal-undirected action vibrator. That is insufficient density for grass silage. This vibrator is much more efficient for maize thickening when nearly double mass density is achieved. Therefore, this type of vibrator is advisable for thickening of big stems plants such as maize and its mixture with red clover. It was established, that thickening of maize – Caucasian goat’s rue (Galega orientalis Lam.) mix (2:1 ratio) by undirected action vibrator – after 20 min of thickening (2×60 kg) gave 425 kg/m3 and 124 kg/m3 of dry matter density respectively. It is not sufficient density for grass thickening. Such vibrator is much more efficient in thickening maize, it reaches bigger mass density – 730 kg/m3 and 223 kg/m3 of dry matter. On the grounds of the research results it can be stated that the vibratory thickener of investigated design (undirected action vibrator) is reasonable to use in thickening maize and maize-red clover mixture. This vibrator is not suitable for thickening of red clover, Caucasian goat’s rue and maize-Caucasian goat’s rue mixtur

Grass silage thickening technology using centrifugal undirected action vibrator

A vibratory device to thicken silage was designed and tested, experimental research was carried out using the device for thickening chopped mass of red clover and maize. Dependences of grass mass density variation on duration of thickening by the device and dependences of relative grass pressure on vibration frequency have been examined and assessed. The research has showed that during vibratory thickening grass layer thickens intensively for 5-10 min and this vibrator is advisable for thickening grass layers of 0.5-0.6 m thickness. After investigation of dependence of grass thickening and grass comparative pressure on vibration frequency it was established that most effectively vibrator works at 43.96 s-1 frequency. Consequently, it is reasonable to thicken grass using undirected action vibrator at the mentioned frequency or close to it. Experimental research has established that red clover density of 350 kg/m3 can be achieved by centrifugal-undirected action vibrator. That is insufficient density for grass silage. This vibrator is much more efficient for maize thickening when nearly double mass density is achieved. Therefore, this type of vibrator is advisable for thickening of big stems plants such as maize and its mixture with red clover. It was established, that thickening of maize – Caucasian goat’s rue (Galega orientalis Lam.) mix (2:1 ratio) by undirected action vibrator – after 20 min of thickening (2×60 kg) gave 425 kg/m3 and 124 kg/m3 of dry matter density respectively. It is not sufficient density for grass thickening. Such vibrator is much more efficient in thickening maize, it reaches bigger mass density – 730 kg/m3 and 223 kg/m3 of dry matter. On the grounds of the research results it can be stated that the vibratory thickener of investigated design (undirected action vibrator) is reasonable to use in thickening maize and maize-red clover mixture. This vibrator is not suitable for thickening of red clover, Caucasian goat’s rue and maize-Caucasian goat’s rue mixtur

The new mathematical model based carotid intima-media thickness and mild cognitive impairment: comparison of manual and semi-automated measurement techniques

An alteration of the cognitive functions plays a crucial role in the quality of life in the elderly. New investigations notice that the thickness of carotid intima-media (CIMT) might help to identify patients with an increased risk of cognitive deterioration. Our aim of the study was to evaluate CIMT of the patients with mild cognitive impairment (MCI) with static (manually) and dynamic (RF-QIMT) ultrasonographic equipments. Our results show that the CIMT was thicker measuring by semi-automated method, than manually and the differences were statistically significant. Our results show no correlation between the CIMT and scores of psychiatric tests, therefore more research is needed for improvement of carotid wall thickening changes in MCI patients

A 3D KINEMATICAL ANALYSIS OF LONG JUMP IN THE “GOLD MEETING RIO OF ATHLETICS 2007”

This study was based on the 3D kinematical analysis of long jump in an official competition of the International Association of Athletics Federation. A six camera kinematical analysis system was used to reconstruct the 3D coordinates of eighteen points, modeling the athlete’s body with the follow segments: head, trunk, arms, forearms, thighs, calves and feet. Several performance variables concerning the center of mass trajectories and velocities were used to characterize and compare the individual jumps. Descriptive statistics was used to compare the results obtained with those found in the literature

T-cell-based diagnosis of tuberculosis infection in children in Lithuania: a country of high incidence despite a high coverage with bacille Calmette-Guerin vaccination

<p>Abstract</p> <p>Background</p> <p>Lithuania is a country with a high incidence of tuberculosis (TB), despite a high coverage with bacille Calmette-Guerin (BCG) vaccination. Until now the only method used to detect latent TB infection was the tuberculin skin test (TST). However, TST may have a cross reactivity to the BCG vaccine and to environmental mycobacteria. The aim of this study was to conduct assessments of the diagnostic accuracy of the T-cell based test (T SPOT TB) for TB in children who had previously been BCG vaccinated and compare these with the results of the TST.</p> <p>Methods</p> <p>Between January 2005 and February 2007, children with bacteriologically confirmed TB, children having contacts with a case of infectious pulmonary TB and children without any known risk for TB were tested with both the TST and T SPOT TB.</p> <p>Results</p> <p>The TST and T SPOT TB tests were positive for all patients in the „culture-confirmed TB“ group. Whereas, in the „high risk for TB“ group, the TST was positive for 60%, but the T SPOT TB test, only for 17.8%. Meanwhile the results for the „low risk for TB“ group were 65.4% and 9.6%, respectively. A correlation between the TST and T SPOT TB was obtained in the "culture-confirmed TB" group where the TST ≥15 mm (r = 0.35, p < 0.001).</p> <p>Conclusion</p> <p>The T-cell based method is more objective than the TST for identifying latent TB infection in children who had been previously BCG vaccinated. This method could be useful in countries like Lithuania where there is a high incidence of TB despite a high coverage with BCG vaccination. It may also help to avoid unnecessary chemoprophylaxis when TST reactions are false-positive.</p

On complex-valued 2D eikonals. Part four: continuation past a caustic

Theories of monochromatic high-frequency electromagnetic fields have been designed by Felsen, Kravtsov, Ludwig and others with a view to portraying features that are ignored by geometrical optics. These theories have recourse to eikonals that encode information on both phase and amplitude -- in other words, are complex-valued. The following mathematical principle is ultimately behind the scenes: any geometric optical eikonal, which conventional rays engender in some light region, can be consistently continued in the shadow region beyond the relevant caustic, provided an alternative eikonal, endowed with a non-zero imaginary part, comes on stage. In the present paper we explore such a principle in dimension $2.$ We investigate a partial differential system that governs the real and the imaginary parts of complex-valued two-dimensional eikonals, and an initial value problem germane to it. In physical terms, the problem in hand amounts to detecting waves that rise beside, but on the dark side of, a given caustic. In mathematical terms, such a problem shows two main peculiarities: on the one hand, degeneracy near the initial curve; on the other hand, ill-posedness in the sense of Hadamard. We benefit from using a number of technical devices: hodograph transforms, artificial viscosity, and a suitable discretization. Approximate differentiation and a parody of the quasi-reversibility method are also involved. We offer an algorithm that restrains instability and produces effective approximate solutions.Comment: 48 pages, 15 figure