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Introduction: Meeting the needs of livestock feed is associated with an increase in planting acreages and increase in yield of forage crops. To ensure their maximum productivity, it is necessary to perform a high quality dosing of the seed material during sowing. This is especially significant when providing small rates of seeding small-seeded crops. Due to the small size of the seed, it is very difficult to distribute them on the feeding area without damaging. Materials and Methods: The members of the Prof. Leshchankin Chair of Agricultural Machines of the National Research Mordovia State University developed a disk device for sowing small-seeded crops to ensure more uniform distribution of seed with minimum of damage. Results: The authors determined the values of the objective function and built the regression equation describing the process of damage of the sowing apparatus, depending on design options. Discussion and Conclusions: For reducing damage to seed of small-seeded crops from the developed disk sowing apparatus, it is necessary to use disks with the maximum possible number of cells and the angle of the seeds reflector should not exceed 15o.

In this article we discuss possible design options for the optical phase reference system, the so called backlink, between two moving optical benches in a LISA satellite. The candidates are based on two approaches: Fiber backlinks, with additional features like mode cleaning cavities and Faraday isolators, and free beam backlinks with angle compensation techniques. We will indicate dedicated ghost beam mitigation strategies for the design options and we will point out critical aspects in case of an implementation in LISA. © Published under licence by IOP Publishing Ltd. DFG/SFB/1128 Deutsches Zentrum für Luft- und Raumfahrt (DLR) Bundesministerium für Wirtschaft und Technologie/50 OQ 0601 NASA/NNX15AC48G

In this study, performance evaluation of an autonomous vehicle storage and retrieval system (AVS/RS) is completed under various pre-defined design scenarios. Design scenarios are considered based on the rack configuration of the warehouse, namely the number of aisles, bays, and tiers, number of autonomous vehicles (AVs), and number of lifts. The system is simulated using ARENA 12-a commercial software. Seven performance measures are observed from the simulation results. These are: the average cycle time, average utilization of the AVs, average utilization of the lifts, average waiting time in the AVs' queue, average waiting time in the lifts' queue, average number of transactions waiting in the AVs' queue, and average number of transactions waiting in the lifts' queue. Total cost of the system is also integrated into the analysis. The results are analyzed via graphs. Various design options and their costs facilitate the evaluation of the best design for the warehouse manager. The case study is completed for a company that utilizes AVS/RS in France. © 2011 Springer-Verlag London Limited.

It is aimed that a new ultrathin shell composite reflector is developed considering different design options to optimize the stiffness/mass ratio, cost, and manufacturing. The reflector is an offset parabolic reflector with a diameter of 6m, a focal length of 4.8m, and an offset of 0.3m and has the ability of folding and self-deploying. For Ku-band missions a full-scale offset parabolic reflector antenna is designed by considering different concepts of stiffening: (i) reflective surface and skirt, (ii) reflective surface and radial ribs, and (iii) reflective surface, skirt, and radial ribs. In a preliminary study, the options are modeled using ABAQUS finite element program and compared with respect to their mass, fundamental frequency, and thermal surface errors. It is found that the option of reflective surface and skirt is more advantageous. The option is further analyzed to optimize the stiffness/mass ratio considering the design parameters of material thickness, width of the skirt, and ply angles. Using the TOPSIS method is determined the best reflector concept among thirty different designs. Accordingly, new design can be said to have some advantages in terms of mass, natural frequency, number of parts, production, and assembly than both SSBR and AstroMesh reflectors. Copyright 2012 Durmu Trkmen et al.

The capabilities of multimodal applications running on the web are well delineated since they are mainly constrained by what their underlying standard mark up language offers, as opposed to hand-made multimodal applications. As the experience in developing such multimodal web applications is growing, the need arises to identify and define major design options of such application to pave the way to a structured development life cycle. This paper provides a design space of independent design options for multimodal web applications based on three types of modalities: graphical, vocal, tactile, and combined. On the one hand, these design options may provide designers with some explicit guidance on what to decide or not for their future user interface, while exploring various design alternatives. On the other hand, these design options have been implemented as graph transformations per-formed on a user interface model represented as a graph. Thanks to a transformation engine, it allows designers to play with the different values of each design option, to preview the results of the transformation, and to obtain the corresponding code on-demand.

Interest on food production systems based on the cultivation of vegetables for future planetary exploration missions is increasing as these units can help overcoming difficult and costly re-supply logistics. In addition to producing edible biomass by growing vegetable species, these systems can be used in closed loop configuration with bio-regenerative life support subsystems for water and CO2 recycling and O2 production. Aiming at this objective, the European Space Agency (ESA) undertook a feasibility study on Closed Loop Food Systems (CLFS) for Low Earth Orbit (LEO), Transit to Mars and Mars Surface scenarios. This paper describes the study's results. Firstly, candidate crops are selected based on nutritional characteristics and aspects like yield, cultivation surface and volume, and generated inedible biomass. A culture plan for these crops is then established. The design process of a Food Production Unit (FPU) begins with the definition of an On Ground Experimental Growth Unit (OGEGU), a ground reference system that is later adapted to the proposed Space scenarios. For Low Earth Orbit (LEO), two secondary structures options (racks and spiral), fitting a Columbus-sized module, are presented and their food production capabilities are analyzed. Similarly, design options for Transit to Mars and Mars Surface are described. Mass, power and volume budgets are determined and the Equivalent System Mass (ESM) methodology is used for trade-off study. For the LEO options process modeling and preliminary mechanical, thermal, safety and logistics analysis are done. Impacts on the International Space Station (ISS) due to potential FPU implementation are also studied. For the Mars surface scenario, an adapted FPU architecture is presented. Interface issues between FPU and bio-regenerative life support systems are also addressed. The study shows that FPU systems for LEO application could deliver ca. 12% of the food requirements, which makes them a very interesting platform for both space agriculture research and complementing nutritional requirements. For the Mars Surface application provision of up to 40 % food requirements is shown possible. Finally, relevant technological gaps identified throughout the study are outlined. Copyright © 2005 SAE International

An integral account of design and analysis of grid-stiffened cylindrical structures is presented. For convenience, a two-phase approach is adopted. In the initial phase, with a view to arriving at a few initial possible optimal configurations, parametric analysis through smeared stiffeners approach is utilised. The ribs, in a filament wound grid-stiffened structure, introduce several additional design elements that result in many possible design configurations; in the initial phase, these design options are efficiently reduced to a few numbers. Finite element modelling is used in the final design and analysis. Rib material is distinct from normal unidirectional composites and this aspect is inherently accounted for in the modelling approaches considered here. Defence Science Journal, 2011, 61(1), pp.88-94 , DOI:http://dx.doi.org/10.14429/dsj.61.482