Alta was a Greek manufacturer of light and heavier three-wheeler trucks, motorcycles and passenger cars. Production of motorcycles and three-wheeler trucks with Sachs 50cc engines started in its first factory in Athens in 1962. The 50S motorcycle model was known for its reliability (some survive to date in good working condition). In 1967 it designed and developed model A700, a heavier three-wheel truck with 2-cylinder BMW 35 hp engine and a payload of 800 kg. The truck, featuring a pleasant design and high reliability became one of the most successful vehicles of its kind in Greece. In 1968 Alta introduced a three-wheel passenger car, model A200 (three wheelers were classified differently according to Greek law). Powered by a Heinkel 200cc engine, the car was based on the German Fuldamobil (also produced by Attica in Greece under licence), but with Alta's own body design. The company moved production to a new, larger factory in Elefsis where it operated until 1978.
Guided by principles of symmetry to achieve a proper balance among model consistency, accuracy, and complexity, this paper proposes a new approach for identifying the unknown parameters of nonlinear one-degree-of-freedom mechanical systems using nonlinear regression methods. To this end, the steps followed in this study can be summarized as follows. Firstly, given a proper set of input time histories and a virtual model with all parameters known, the dynamic response of the mechanical system of interest, used as output data, is evaluated using a numerical integration scheme, such as the classical explicit fixed-step fourth-order Runge-Kutta method. Secondly, the numerical values of the unknown parameters are estimated using the Levenberg-Marquardt nonlinear regression algorithm based on these inputs and outputs. To demonstrate the effectiveness of the proposed approach through numerical experiments, two benchmark problems are considered, namely a mass-spring-damper system and a simple pendulum-damper system. In both mechanical systems, viscous damping is included at the kinematic joints, whereas dry friction between the bodies and the ground is accounted for and modeled using the Coulomb friction force model. While the source of nonlinearity is the frictional interaction alone in the first benchmark problem, the finite rotation of the pendulum introduces geometric nonlinearity, in addition to the frictional interaction, in the second benchmark problem. To ensure symmetry in explaining model behavior and the interpretability of numerical results, the analysis presented in this paper utilizes five different input functions to validate the proposed method, representing the initial phase of ongoing research aimed at applying this identification procedure to more complex mechanical systems, such as multibody and robotic systems. The numerical results from this research demonstrate that the proposed approach effectively identifies the unknown parameters in both benchmark problems, even in the presence of nonlinear, time-varying external input actions.
Restricting milk or milk replacer (MR) fed to dairy calves to 10% of body weight at 12.5% total solids (TS) concentration is a common feeding strategy that promotes early weaning and lowers total feed costs for raising young calves. However, this strategy has been associated with inferior performance and compromised welfare. Because a restricted liquid nutrition plan limits calf growth due to limited supply of nutrients, research on increased supply of nutrients from liquid has shown improved growth, health, and welfare of calves. Nutrient supply may be increased by feeding larger amounts of milk or MR averaging 12.5% TS, or by increasing TS above the usual 12.5% TS by increasing MR TS concentration alone (TS+), or by increasing TS concentration and volume simultaneously (TSV+). The objective of this review is to discuss liquid nutrition plans with greater TS concentration in MR or in milk diets, considering the effects of such strategies on performance and digestive tract development before weaning and the future performance of dairy calves. This review will focus on liquid nutrition plans that are based on increased TS concentration (i.e., TS+ or TSV+); therefore, enhanced liquid nutrition plans based only on increased volumes will not be the discussed. Improved growth rates have been observed in calves fed TSV+ programs. However, reduced starter intake preweaning can also have negative effects on dry matter intake, average daily gain, and digestibility postweaning. Feeding a TS+ program may reduce impairment of starter intake and therefore have positive effects on performance, nutrient digestibility, and health. When considering an accelerated nutrition plan with TS+ or TSV+, it is important to consider osmolality of the liquid diet. Further studies are necessary to confirm this hypothesis and the cost-benefit of alternative liquid nutrition plans, as well as the optimal TS concentration of milk or MR fed to dairy calves.
Background RLS-0071 is a novel 15 amino acid peptide dual-targeting anti-inflammatory inhibitor of complement and neutrophil effectors. RLS-0071 inhibits classical complement pathway activation at C1 and blocks the enzymatic activity of myeloperoxidase that leads to the generation of hypochlorous acid and induces NETosis. This peptide is being developed for the treatment of neonatal hypoxic ischemic encephalopathy (HIE) and neutrophilic pulmonary diseases. Methods This was a first in human clinical trial in healthy volunteers to assess safety and pharmacokinetics of single and multiple ascending doses of RLS-0071. Results RLS-0071 single and multiple doses were not associated with any clinically significant changes in safety parameters, laboratory test results or ECG measurements. Adverse events were similar between active drug and placebo groups. The pharmacokinetic profile demonstrated dose proportionality and two-compartment kinetics with rapid tissue distribution. Exploratory biomarker and target engagement assays demonstrated dose dependent classical complement pathway inhibition and myeloperoxidase binding. Discussion/Conclusion RLS-0071 was shown to be safe and well-tolerated at all doses tested with rapid tissue distribution and target engagement for both the classical complement pathway and myeloperoxidase. The findings are supportive of further clinical development and evaluation of RLS-0071 in conditions such as HIE and acute pulmonary diseases. Trial registration ClinicalTrials.gov Identifier: NCT05298787 March 28, 2022. Retrospectively registered.
Nowadays more and more constraints are imposed on the designs of electrical machines: lower acoustic noise, less maintenance costs, high efficiency, less losses. An accurate estimation of losses becomes more and more important in the design of electrical machines, this estimation is the key issue of the thermal design. In this paper, we present and explain a homogenization method used in the case of finite element method to consider the stranded conductors in electric machines, transformers.
