A dynamic unreliability assessment and optimal maintenance strategies for multistate weighted k‐out‐of‐n:F systems

In this paper, a dynamic evaluation of the multistate weighted k‐out‐of‐n:F system is presented in an unreliability viewpoint. The expected failure cost of components is used as an unreliability index. Using failure cost provides an opportunity to employ financial concepts in system unreliability estimation. Hence, system unreliability and system cost can be compared easily in order to making decision. The components' probabilities are computed over time to model the dynamic behavior of the system. The whole system has been assessed by recursive algorithm approach. As a result, a bi‐objective optimization model can be developed to find optimal decisions on maintenance strategies. Finally, the application of the proposed model is investigated via a transportation system case. Matlab programming is developed for the case, and genetic algorithm is used to solve the optimization model. Copyright © 2016 John Wiley & Sons, Ltd.     

Compatibilized natural rubber/recycled ethylene-propylene-diene rubber blends by biocompatibilizer

Biocompatibilizer-based refined, bleached, deodorized palm stearin was successfully used as compatibilizer for natural rubber/recycled ethylene–propylene–diene rubber (NR/R-EPDM) blends. It seems effective in improving the state of cure, tensile properties, as well as the swelling resistance and morphology of the blends, indicating an improvement in compatibility between the NR matrix and R-EPDM rendered by biocompatibilizer. This was clearly verified by the dynamic mechanical properties of the blends. The dynamic responses obtained were clearly corresponding to the swelling result. It proves that the cross-link density plays a major role in the changes of storage modulus and degree of entanglement.     

On minimum metric dimension of honeycomb networks

A minimum metric basis is a minimum set W of vertices of a graph G(V,E) such that for every pair of vertices u and v of G, there exists a vertex wW with the condition that the length of a shortest path from u to w is different from the length of a shortest path from v to w. The honeycomb and hexagonal networks are popular mesh-derived parallel architectures. Using the duality of these networks we determine minimum metric bases for hexagonal and honeycomb networks.     

Sr(Ag1−xLix)2Se2 and [Sr3Se2][(Ag1−xLix)2Se2] Tunable Direct Band Gap Semiconductors

Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid-state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two-dimensional Sr(Ag_1−xLi_x)₂Se₂ layered phases. With increased LiOH/LiCl ratio or reaction temperature, Li partially substituted Ag to form solid solutions of Sr(Ag_1−xLi_x)₂Se₂ with x up to 0.45. In addition, a new type of intergrowth compound [Sr₃Se₂][(Ag_1−xLi_x)₂Se₂] was synthesized upon further reaction of Sr(Ag_1−xLi_x)₂Se₂ with SrSe. Both Sr(Ag_1−xLi_x)₂Se₂ and [Sr₃Se₂][(Ag_1−xLi_x)₂Se₂] exhibit a direct band gap, which increases with increasing Li substitution (x). Therefore, the band gap of Sr(Ag_1−xLi_x)₂Se₂ can be precisely tuned via fine-tuning x that is controlled by only the flux ratio and temperature.     

Linear Wirelength of Folded Hypercubes

Manuel et al. (Discret. Appl. Math. 157(7):1486–1495, 2009) obtained the exact wirelength of an r-dimensional hypercube into a path as well as a 2^?r/2?×2^ér/2ù{2^{\lfloor r/2\rfloor}\times 2^{\lceil r/2\rceil}} grid and conjectured the same for a folded hypercube. In this paper we solve the edge isoperimetric problem for folded hypercubes and thereby obtain the exact wirelength of folded hypercubes into paths. Further we compute the exact wirelength of the r-dimensional folded hypercubes into 2 ^k × 2 ^r−k grids.     

Synthesis of Aromatic Amino Acid Amides

Aromatic amino esters, in toluene or water, react with aqueous ammonium hydroxide to give moderate to high yields of the corresponding amides.     

Synthetic study on the relationship between structure and sweet taste properties of steviol glycosides

The structure activity relationship between the C??-C?? methylene double bond on the aglycone of steviol glycosides and the corresponding impact on their sweet taste has been reported here for the first time. It has been observed that converting stevioside and rebaudioside A to their corresponding ketones by switching the doubly bonded methylene on C-17 for a ketone group actually removes the sweet taste properties of these molecules completely. Regenerating the original molecules tends to restore the sweet taste of both the steviol glycosides. Thus this C??-C?? methylene double bond in rebaudioside A and stevioside can be regarded as a pharmacophore essential for the sweetness property of these molecules.     

Ionic liquids-assisted greener preparation of silver nanoparticles

1. Download : Download high-res image (298KB)
2. Download : Download full-size image

     

Exact wirelength of hypercubes on a grid

Grid embeddings are used not only to study the simulation capabilities of a parallel architecture but also to design its VLSI layout. In addition to dilation and congestion, wirelength is an important measure of an embedding. There are very few papers in the literature which provide the exact wirelength of grid embedding. As far as the most versatile architecture hypercube is concerned, only approximate estimates of the wirelength of grid embedding are available. In this paper, we give an exact formula of minimum wirelength of hypercube layout into grids and thereby we solve completely the wirelength problem of hypercubes into grids.We introduce a new technique to estimate the wirelength of a grid embedding. This new technique is based on a Congestion Lemma and a Partition Lemma which we study in this paper.     

Zur volumetrischen Bestimmung des Wismuts

Ohne Zusammenfassung(Mitteilung aus dem Laboratorium des Herrn Prof. Dr. J. Habermann, k. k. technische Hochschule in Brünn.)