How to manage value creation and how to maximize the potential of collaborations are challenging issues in the management of cross-sector collaborations. One strategic tool for addressing these areas ...of concern is value network mapping; this serves as the starting point for value network analysis, which is used to maximize innovations by forging stronger value creation links with strategic partners. The objective of this study was to design and implement a method for value network mapping that would increase our understanding of how new value can be created in cross-sector collaborations. The proposed mapping method also permits the assessment of current and potential value networks; e.g., what value is exchanged in the current collaborative state and what new value can be created through the proper management of a value network? Using the case study of a collaboration among the public, private, and non-profit sectors for elderly care, this paper describes, step by step, how the proposed value network mapping method can be applied in practice to help managers and experts understand how to develop complex value network maps, how new values can be created, and how to maximize the potential of a collaboration.
Numerical investigations on stratospheric airships of different tail configurations are conducted based on the Reynolds-averaged N-S equations and k-ω SST turbulent model in the condition of the same ...volume and total area of the tails. The influence of tail configurations on the force and moment characteristics as well as flow phenomena on both hull and fins are analyzed. In particular, the hull-fin mutual interference effect is discussed compared to the bare hull performance. It is found that a cross-shaped tail produces a superior lift characteristic and stability at high angle but greater drag due to horizontal fins, both in pitch and yaw channels than the inverted Y and X shaped tail. The hull-fin interference generates additional hull lift, drag and an offsetting moment and causes side edge separation on the suction side of horizontal (side) fins in the cross (inverted Y and X shaped) tail configuration. The inverted Y-shaped tail provides the greatest interference drag. These investigations serve to provide references for airship configuration design.
The Tom Swiftbooks were published by a huge fiction-production company, the Stratemeyer Publishing Syndicate, which brought out other successful cycles of juvenile fiction, including the Nancy ...Drewand the Hardy Boys series. The elephant hunters at last succeeded in closing the gate, blocking the chance of any more animals to escape.
The use of unmanned aerial vehicles (UAV) has become widespread in recent years. UAVs pioneers scientific research and variety of use in space technologies, also it has a wide range of use in sectors ...such as military, commercial, and security. The control of flying vehicles has always been difficult due to disruptive inputs. This study aims to design and control the attitude and altitude of an autonomous octocopter with the NARX NN algorithm to be an alternative to commonly used control algorithms on UAVs with continuous learning capability. Roll, pitch, yaw, and altitude control of eight rotor multi-copter also known as octocopter have been designed. The non-linear mathematical model of the octocopter has been implemented on Matlab Simulink with the help of the Newton-Euler method. A rigid body model has been designed on Solidworks to identify mass properties and inertial moments of the proposed octocopter design. Classical proportional-integratorderivative (PID) algorithms and dynamic time series non-linear autoregressive exogenous input (NARX) neural networks (NN) have been used for the altitude and attitude control of the feedback loop system. The PID controller gains have been calculated with the help of the Ziegler-Nichols method. The NARX NN controllers have trained with the Levenberg-Marquardt algorithm. The performances of the designed controllers for each maneuver have been compared under Gaussian noise. The PID and NARX NN controllers have performed similar results in the simulation environment.
Transport vehicle industry is suffering a diffused technological maturity. Energy efficiency is increasing with a certain velocity. But many factors in car development are playing against. A critical ...literature review about technological maturity symptoms and industrial grade design methods is presented for the current research paper. In particular Multidisciplinary Design Optimization and Modular System Design has been considered. A technical and scientific discussion, is performed focusing on the technological effect they are generating. A possible answer comes from the MAAT 7th framework Program which defined a novel design method initially conceived for airships. It has been defined CDE, Constructal Design for Efficiency. It is specifically based on Constructal law and second Principle of Thermodynamics and aims to produce an original methodological synthesis of Modular Design principles and Multidisciplinary Optimization harmonizing them by thermodynamic principles. The result of this process allows tuning CDE on the road through an effective generalization of the preliminary CDE concept. The schematization of the necessary design process of a vehicle has presented and discussed.
Spherical shells are ubiquitous in nature and engineering for their simple geometry and excellent load-bearing capacity. A long-standing topic of spherical shells subject to uniform external pressure ...is their highly unstable post-buckling response that leads to a catastrophic collapse. This type of failure fully exhausts the load-bearing capacity of the shell, and it is thus detrimental for traditional engineering applications. On the other hand, recent advances in soft robotics and metamaterials demonstrate that geometric nonlinearities and elastic instabilities can be harnessed to generate distinctive functions, such as shape morphing, fast motion, and logic operation.This thesis proposes the use of a large axisymmetric imperfection to control the buckling mode of spherical shells, and demonstrates its application when integrated into a soft bi-shell valve for the fast actuation of soft robots. On the first front, the proposed imperfection can escape the classical bifurcation of perfect spherical shells, and induce snap-through buckling followed by a stable post-buckling; this response provides increasing pressure resistance over a large change in volume. The buckling of the imperfect shell is investigated through a theoretical study that employs exact expressions of the middle surface strains, curvature changes, and live pressure loading along with validating experiments and numerical simulations. The post-buckling characteristics and transition between four buckling modes can be programmed by tuning the defect geometry and shell radius to thickness ratio. On the second front, a new concept for soft valves is proposed: a bi-shell valve consisting of an imperfect shell and a shallow spherical cap. The bi-shell valve harnesses the snap-through interaction of the constituent shells to convert a slowly imparted volume into a fast volume output. Upper bounds and performance metrics are presented to guide the design of the bi-shell valve, and its performance is illustrated through an application that demonstrates the fast actuation of a soft striker.Overall, the work in this thesis contributes to unveil original aspects of shell buckling with results that are promising for diverse applications. Geometric imperfections can be programmed into spherical shells to trigger new buckling modes that can be exploited for the design of soft robots, mechanical metamaterials, and soft matter. Furthermore, the bi-shell valve concept here introduced can inspire the design of future soft valves with unique actuation modes for soft pneumatic robots
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