Design considerations in the creation and maintenance of electrostatic cleanliness for solar electrically propelled spacecraft

Author(s):  
J. SELLEN, JR. ◽  
D. FITZGERALD
Author(s):  
D T Pham ◽  
S S Dimov ◽  
B J Peat

Intelligent product manuals are designed to allow product users to utilize a product as easily, effectively and with as little additional care as possible while minimizing support costs for manufacturers and suppliers. It is first shown how intelligent product manuals address these objectives by utilizing electronic, multimedia and knowledge-based technologies to provide active assistance to the user of the product during tasks such as installation, operation and maintenance. An architecture for the creation and deployment of an intelligent product manual is then proposed and general design considerations are outlined. Finally, four implementation approaches, based on XML, SGML, HTML and PDF technologies, are compared against a set of selection criteria. It is concluded that simple, low-cost solutions are available, which can provide significant benefits for appropriate businesses, including smaller companies.


2020 ◽  
Vol 72 (5) ◽  
Author(s):  
Lindsie Jeffries ◽  
David Lentink

Abstract Probabilistic mechanical fasteners are used to provide secure, reversible, and repeatable attachments in both nature and industry. Since the first observation of this mechanism in nature, which led to the creation of hook-and-loop fasteners, there has been a multitude of variations on the basic hook-and-loop design. However, few fastener designs have looked back to nature for inspiration in creating novel products or improving existing fasteners. Given the diverse probabilistic mechanical fasteners employed in nature, there is opportunity to further the research and development of these underdeveloped fasteners. To this end, we present a framework which describes the theory, design considerations, modelling, and mechanical testing required to study probabilistic mechanical fasteners. We further provide a comparison of the performance of existing probabilistic mechanical fasteners found in nature and industry as a reference for novel bio-inspired designs. Finally, we discuss current areas of application and future opportunities for fastener innovation.


Author(s):  
Oliver Dreon ◽  
Greg Szczyrbak

Gamification is becoming increasingly popular in both K-12 and higher education settings. By infusing game elements into learning environments, educators believe that students will be more engaged and more motivated to learn (Bowman, 1982, Deterding, 2012, Dominguez et al, 2013). But what about the use of gamification to support the professional development of educators? What impact would gamification have on the participation and motivation of professors and faculty involved in an intensive professional development experience? This chapter describes the creation and implementation of Level Up, a two week long professional development game involving twenty faculty member participants. The chapter outlines the process of designing the game and the game elements used throughout its implementation. The chapter also examines some challenges the designers and participants experienced during the game implementation and provides several design considerations for professional developers who wish to gamify their faculty programs.


2020 ◽  
Vol 43 ◽  
Author(s):  
Stefen Beeler-Duden ◽  
Meltem Yucel ◽  
Amrisha Vaish

Abstract Tomasello offers a compelling account of the emergence of humans’ sense of obligation. We suggest that more needs to be said about the role of affect in the creation of obligations. We also argue that positive emotions such as gratitude evolved to encourage individuals to fulfill cooperative obligations without the negative quality that Tomasello proposes is inherent in obligations.


Author(s):  
S.D. Smith ◽  
R.J. Spontak ◽  
D.H. Melik ◽  
S.M. Buehler ◽  
K.M. Kerr ◽  
...  

When blended together, homopolymers A and B will normally macrophase-separate into relatively large (≫1 μm) A-rich and B-rich phases, between which exists poor interfacial adhesion, due to a low entropy of mixing. The size scale of phase separation in such a blend can be reduced, and the extent of interfacial A-B contact and entanglement enhanced, via addition of an emulsifying agent such as an AB diblock copolymer. Diblock copolymers consist of a long sequence of A monomers covalently bonded to a long sequence of B monomers. These materials are surface-active and decrease interfacial tension between immiscible phases much in the same way as do small-molecule surfactants. Previous studies have clearly demonstrated the utility of block copolymers in compatibilizing homopolymer blends and enhancing blend properties such as fracture toughness. It is now recognized that optimization of emulsified ternary blends relies upon design considerations such as sufficient block penetration into a macrophase (to avoid block slip) and prevention of a copolymer multilayer at the A-B interface (to avoid intralayer failure).


Author(s):  
Y. Harada ◽  
K. Tsuno ◽  
Y. Arai

Magnetic objective lenses, from the point of view of pole piece geometry, can he roughly classified into two types, viz., symmetrical and asymmetrical. In the case of the former, the optical properties have been calculated by several authors1-3) and the results would appear to suggest that, in order to reduce the spherical and chromatic aberration coefficients, Cs and Cc, it is necessary to decrease the half-width value of the axial field distribution and to increase the peak flux density. The expressions for either minimum Cs or minimum Cc were presented in the form of ‘universal’ curves by Mulvey and Wallington4).


Author(s):  
Nicholas Temperley
Keyword(s):  

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