The combination of structure and material distribution ensures functionality of the honeybee wing-coupling mechanism

Fore- and hindwings of honeybees are coupled and synchronized to flap by means of a forewing posterior recurved margin (PRM) and hindwing hamuli which constitute a hook-furrow coupling. Morphological analysis...

Design of telescopic nadir imager for geomorphology (TENGOO) and observation of surface reflectance by optical chromatic imager (OROCHI) for the Martian Moons Exploration (MMX)

The JAXA’s Martian Moons Exploration (MMX) mission is planned to reveal the origin of Phobos and Deimos. It will remotely observe both moons and return a sample from Phobos. The nominal instruments include the TElescopic Nadir imager for GeOmOrphology (TENGOO) and Optical RadiOmeter composed of CHromatic Imagers (OROCHI). The scientific objective of TENGOO is to obtain the geomorphological features of Phobos and Deimos. The spatial resolution of TENGOO is 0.3 m at an altitude of 25 km in the quasi-satellite orbit. The scientific objective of OROCHI is to obtain material distribution using spectral mapping. OROCHI possesses seven wide-angle bandpass imagers without a filter wheel and one monochromatic imager dedicated to the observation during the landing phase. Using these two instruments, we plan to select landing sites and obtain information that supports the analysis of return samples. Graphical Abstract

Research on Decision Model of Emergency Material Distribution Based on Random Information

As an important link of emergency logistics, emergency material distribution has been widely concerned and applied in the development of today’s society. From the consideration of the fairness and efficiency of material distribution, there is a kind of negative and negative relationship between them. As a lever, information updating can be used to solve the problems of fairness and efficiency in the distribution of emergency supplies. Based on fuzzy objective programming, the classification decision model of emergency materials is discussed in this paper.

A pessimistic bilevel stochastic problem for elastic shape optimization

We consider pessimistic bilevel stochastic programs in which the follower maximizes over a fixed compact convex set a strictly convex quadratic function, whose Hessian depends on the leader’s decision. This results in a random upper level outcome which is evaluated by a convex risk measure. Under assumptions including real analyticity of the lower-level goal function, we prove the existence of optimal solutions. We discuss an alternate model, where the leader hedges against optimal lower-level solutions, and show that solvability can be guaranteed under weaker conditions in both, a deterministic and a stochastic setting. The approach is applied to a mechanical shape optimization problem in which the leader decides on an optimal material distribution to minimize a tracking-type cost functional, whereas the follower chooses forces from an admissible set to maximize a compliance objective. The material distribution is considered to be stochastically perturbed in the actual construction phase. Computational results illustrate the bilevel optimization concept and demonstrate the interplay of follower and leader in shape design and testing.

Transport Performance of a Steeply Situated Belt Conveyor

The paper presents a methodology for determining the volume of a batch of conveyed material located before a transverse partition of a certain height and the distance over which the batch of material extends on the working surface of the conveyor belt along its longitudinal axis. Knowing the geometric dimensions of the transported batch of material makes it possible to appropriately set the spacing of the belt cleats and thereby to optimally determine the conveying performance of the inclined belt conveyor. When the angle of inclination of a conveyor with a straight idler frame is equal to the angle of surcharge of the conveyed material, then no layer of material is carried on the surface of the belt. If the conveyor belt is guided along a trough idler frame, only the lower cross-section of the filling of material is used. An increase in the cross-section of the belt load of a conveyor inclined at an angle, which exceeds the angle of repose of the conveyed material, can be achieved by installing regularly spaced belt cleats around the circumference of the working surface of the endless loop of the conveyor belt. The volume of the batch of material retained by the belt cleat depends on the height and width of the cleat and whether or not the conveyor belt is provided with corrugated side edges. The paper presents theoretically determined relationships that can be used to determine the size of the transverse and longitudinal area and the volume of the batch of material spread on the surface of the conveyor belt in front of the cleat. The experiments performed provide the distances of the material distribution on the surface of the conveyor belt depending on the height of the cleat and the angle of inclination of the conveyor belt.

Proper Generalized Decomposition for Parametric Study and Material Distribution Design of Multi-Directional Functionally Graded Plates Based on 3D Elasticity Solution

The use of mesh-based numerical methods for a 3D elasticity solution of thick plates involves high computational costs. This particularly limits parametric studies and material distribution design problems because they need a large number of independent simulations to evaluate the effects of material distribution and optimization. In this context, in the current work, the Proper Generalized Decomposition (PGD) technique is adopted to overcome this difficulty and solve the 3D elasticity problems in a high-dimensional parametric space. PGD is an a priori model order reduction technique that reduces the solution of 3D partial differential equations into a set of 1D ordinary differential equations, which can be solved easily. Moreover, PGD makes it possible to perform parametric solutions in a unified and efficient manner. In the present work, some examples of a parametric elasticity solution and material distribution design of multi-directional FGM composite thick plates are presented after some validation case studies to show the applicability of PGD in such problems.