Preliminary weight and costs of sandwich panels to distribute concentrated loads

Minimum mass honeycomb sandwich panels were sized for transmitting a concentrated load to a uniform reaction through various distances. The form skin gages were fully stressed with a finite element computer code. The panel general stability was evaluated with a buckling computer code labeled STAGS-B. Two skin materials were considered; aluminum and graphite-epoxy. The core was constant thickness aluminum honeycomb. Various panel sizes and load levels were considered. The computer generated data were generalized to allow preliminary least mass panel designs for a wide range of panel sizes and load intensities. An assessment of panel fabrication cost was also conducted. Various comparisons between panel mass, panel size, panel loading, and panel cost are presented in both tabular and graphical form

Lunar penetrometer Patent

Development and characteristics of pentrometer for measuring physical properties of lunar surfac

Analytical Rescaling of Polymer Dynamics from Mesoscale Simulations

We present a theoretical approach to scale the artificially fast dynamics of simulated coarse-grained polymer liquids down to its realistic value. As coarse-graining affects entropy and dissipation, two factors enter the rescaling: inclusion of intramolecular vibrational degrees of freedom, and rescaling of the friction coefficient. Because our approach is analytical, it is general and transferable. Translational and rotational diffusion of unentangled and entangled polyethylene melts, predicted from mesoscale simulations of coarse-grained polymer melts using our rescaling procedure, are in quantitative agreement with united atom simulations and with experiments.Comment: 6 pages, 2 figures, 2 table

Services diagnostic and needs assessment study

Liberalisation of trade in services and associated domestic reforms is fundamental to the realisation of the ASEAN Economic Community (AEC). However, this requires real (‘on the ground’) liberalisation, not simply “on paper” liberalisation in the form of commitments under the ASEAN Framework Agreement on Services (AFAS), a sideshow in services liberalisation. The decision by leaders to form an AEC covering also the free flow of services has put the emphasis very much on ensuring each ASEAN Member State (AMS) removes restrictions affecting trade in services (including related foreign investment) and implement related reforms. However, the diagnostic analysis presented in this Services Diagnostic and Needs Assessment Study (SDNAS), including in the in-country reports, suggests this is not happening, or at least is going very slowly, especially when set against the adopted start date for the AEC of 2015. Hence, key and effective technical assistance and capacity building is needed to advance ‘on the ground’ liberalisation of services and related reforms. The in-country fieldwork and other analysis undertaken in the SDNAS helped identify constraints and provided a list of potential technical assistance and capacity building projects to help address them, both from a primarily cross-cutting but also a sectoral perspective. The SDNAS has also adopted an economic framework based on the fundamental benefits of unilateral liberalisation and a strategic structured approach, to identify key areas (‘umbrellas’) needing technical assistance and capacity building activities, such as strengthening the evidence base, promoting transparency, developing strategies and planning, and raising understanding and awareness. Key activity clusters were also identified within these three ‘umbrellas’, such as policy analysis, services policy visions, and organisations for dialogues, respectively. Individual priority technical assistance and capacity building project proposals within these clusters were determined using a cost-benefit analytical approach. The SNDAS importantly recommends the need to re-balance much of the technical assistance and capacity building activities away from being directed at servicing the AFAS trade negotiations and focusing on ‘on-paper’ liberalisation towards efforts to build transparency and fundamental support for services trade liberalisation and related reforms in AMS. This is what is required to achieve the necessary ‘on-the-ground’ changes to achieve the AEC. This is consistent with international experience that significant ‘on-the-ground’ services liberalisation and related reforms requires unilateral efforts, and that trade negotiations have generally failed to deliver such changes. With this in mind, the SNDAS has developed and recommended a number of detailed proposed technical assistance and capacity building project templates

Multiscale Modeling of Binary Polymer Mixtures: Scale Bridging in the Athermal and Thermal Regime

Obtaining a rigorous and reliable method for linking computer simulations of polymer blends and composites at different length scales of interest is a highly desirable goal in soft matter physics. In this paper a multiscale modeling procedure is presented for the efficient calculation of the static structural properties of binary homopolymer blends. The procedure combines computer simulations of polymer chains on two different length scales, using a united atom representation for the finer structure and a highly coarse-grained approach on the meso-scale, where chains are represented as soft colloidal particles interacting through an effective potential. A method for combining the structural information by inverse mapping is discussed, allowing for the efficient calculation of partial correlation functions, which are compared with results from full united atom simulations. The structure of several polymer mixtures is obtained in an efficient manner for several mixtures in the homogeneous region of the phase diagram. The method is then extended to incorporate thermal fluctuations through an effective chi parameter. Since the approach is analytical, it is fully transferable to numerous systems.Comment: in press, 13 pages, 7 figures, 6 table

Hydrogen-induced reversible spin-reorientation transition and magnetic stripe domain phase in bilayer Co on Ru(0001)

Imaging the change in the magnetization vector in real time by spin-polarized low-energy electron microscopy, we observed a hydrogen-induced, reversible spin-reorientation transition in a cobalt bilayer on Ru(0001). Initially, hydrogen sorption reduces the size of out-of-plane magnetic domains and leads to the formation of a magnetic stripe domain pattern, which can be understood as a consequence of reducing the out-of-plane magnetic anisotropy. Further hydrogen sorption induces a transition to an in-plane easy-axis. Desorbing the hydrogen by heating the film to 400 K recovers the original out-of-plane magnetization. By means of ab-initio calculations we determine that the origin of the transition is the local effect of the hybridization of the hydrogen orbital and the orbitals of the Co atoms bonded to the absorbed hydrogen.Comment: 5 figure