Systemic reliability of bridge networks with mobile sensing-based model updating for postevent transportation decisions

This paper proposes the upscaling of conventional individual bridge health monitoring problems into urban regions and transportation networks via mobile and smart sensing techniques together with an innovative reconnaissance procedure. The paper associates structural failure probabilities with systemic features and proposes decision criteria to optimize postdisaster actions. Twenty bridges constituting transportation network infrastructure compose the testbed region and utilize smartphone accelerometers for dynamics characterization in a vibration-based framework. In this framework, reconnaissance output serves for model development, and mobile sensor data enable finite element model updating. Structural reliability analyses merged in a chain setting generate the systemic behavior of cascaded bridge performance. Combining systemic reliability with transportation and health services demand, one can optimize the response strategies of the bridge population and strategize disaster-related decisions in a postevent assessment setting. Based on a testbed region with remote access to nearby vicinities, 18 earthquake scenarios are conducted to visualize the optimal evacuation strategies on the network, taking systemic bridge performance into consideration. Cost-free mobile sensing support adds one more fundamental information source for reducing the uncertainty of the models and, therefore, improves associated mitigation actions.     

Encoding Information on the Excited State of a Molecular Spin Chain

The quantum states of nano-objects can drive electrical transport properties across lateral and local-probe junctions. This raises the prospect, in a solid-state device, of electrically encoding information at the quantum level using spin-flip excitations between electron spins. However, this electronic state has no defined magnetic orientation and is short-lived. Using a novel vertical nanojunction process, these limitations are overcome and this steady-state capability is experimentally demonstrated in solid-state spintronic devices. The excited quantum state of a spin chain formed by Co phthalocyanine molecules coupled to a ferromagnetic electrode constitutes a distinct magnetic unit endowed with a coercive field. This generates a specific steady-state magnetoresistance trace that is tied to the spin-flip conductance channel, and is opposite in sign to the ground state magnetoresistance term, as expected from spin excitation transition rules. The experimental 5.9 meV thermal energy barrier between the ground and excited spin states is confirmed by density functional theory, in line with macrospin phenomenological modeling of magnetotransport results. This low-voltage control over a spin chain's quantum state and spintronic contribution lay a path for transmitting spin wave-encoded information across molecular layers in devices. It should also stimulate quantum prospects for the antiferromagnetic spintronics and oxides electronics communities.     

Stochastic optimization of nonlinear energy sinks

Nonlinear energy sinks (NES) are a promising technique to achieve vibration mitigation. Through nonlinear stiffness properties, NES are able to passively and irreversibly absorb energy. Unlike the traditional Tuned Mass Damper (TMD), NES absorb energy from a wide range of frequencies. Many studies have focused on NES behavior and dynamics, but few have addressed the optimal design of NES. Design considerations of NES are of prime importance as it has been shown that NES dynamics exhibit an acute sensitivity to uncertainties. In fact, the sensitivity is so marked that NES efficiency is near-discontinuous and can switch from a high to a low value for a small perturbation in design parameters or loading conditions. This article presents an approach for the probabilistic design of NES which accounts for random design and aleatory variables as well as response discontinuities. In order to maximize the mean efficiency, the algorithm is based on the identification of regions of the design and aleatory space corresponding to markedly different NES efficiencies. This is done through a sequence of approximated sub-problems constructed from clustering, Kriging approximations, a support vector machine, and Monte-Carlo simulations. The refinement of the surrogates is performed locally using a generalized max-min sampling scheme which accounts for the distributions of random variables. The sampling scheme also makes use of the predicted variance of the Kriging surrogates for the selection of aleatory variables values. The proposed algorithm is applied to three example problems of varying dimensionality, all including an aleatory excitation applied to the main system. The stochastic optima are compared to NES optimized deterministically.     

Microstructure,fluidity, and mechanical properties of semi-solid processed ductile iron

This research is directed towards studying the effect of semi-solid processing (using cooling plate technique) on the microstructure, fluidity, and mechanical properties of ductile iron (DI). Sand mold castings with constant width of 25 mm and length of 150 mm with the thicknesses of 6, 12, 18, and 25 mm were used in this study. Microstructure, fluidity, and tensile strength properties were investigated as a function of fraction of solid. The results indicated that by increasing fraction of solid microstructure becomes finer and more globular. However, increasing primary fraction of solid increases the cementite content in the matrix. Above a certain fraction of solid (f _s = 0.28, f _s = 0.1, and f _s = 0.05 for 25, 18, and 12 mm wall thickness, respectively), the fluidity of semi-solid processed DI decreases steeply. For low fraction of solid (f _s ≤ 0.15), increasing the fraction of solid results in an increment in the tensile strength, comparing with the ordinary DI due to the fine and globular structure formation. Any further increment of fraction of solid (f _s > 0.15) leads to the cementite increment and gas porosity formation, consequently the tensile strength decreased. The fraction of solid of DI and casting wall thickness should be considered in order to obtain the best combination of microstructure, fluidity, and mechanical properties of semi-solid processed DI.     

Oil: Source rock correlations of Al Baraka oil field,Komombo basin,South Egypt: An implication from biomarkers characteristics

The objectives of this study are the correlation between the oil samples recovered from the Lower Cretaceous reservoirs and Lower and Upper Cretaceous source rocks. The investigated biomarkers of five oils indicated the oils were derived from mixed marine and terrigenous (lacustrine) organic matter and deposited under suboxic to anoxic conditions. These oils were also generated from source rocks of high thermal maturity at the peak oil window. So, based on the molecular indicators of organic source input,depositional environment and maturity parameters of oils and extracts, we can conclude that the oil recovered from Al Baraka oil field were derived from Lower Cretaceous source rocks especially KomOmbo (B) source rocks where it reached the oil window. Furthermore, we can indicate that the other lower Cretaceous formations as Abu Ballas Formation will have the opportunity to generate and expel oil at the deeper part of the basin as shown in the eastern part of the basin.     

The schistosome granuloma: characterization of lymphocyte migration, activation, and cytokine production

Granuloma formation and its regulation are dependent on lymphocytes. Therefore, we compared the characteristics of lymphocytes derived from the spleens and granulomas of Schistosoma mansoni-infected mice during the course of their disease. We examined lymphocyte cell cycle kinetics, migration, expression of activation Ags (CD69 and IL-2R), cytokine production (IL-2, IL-4, IFN-gamma), and apoptosis. Lymphocytes in the G2/M phase of the cell cycle and high levels of lymphocyte intracellular IL-2 were found in the spleen but not in the granuloma. Cell trafficking experiments showed Ag-specific recruitment of schistosomal egg Ag (SEA)-reactive lymphoblasts into granulomas in vivo, as well as recruitment to, residence within, and egress from granulomas in vitro. Granuloma-derived lymphocytes were more highly activated than splenic lymphocytes based on higher levels of CD69 and IL-2R expression. While the granuloma microenvironment was rich in Th2 cytokines, during peak granuloma formation, the lymphocytes per se from the spleen and granuloma did not exhibit a dominant Th1 or Th2 cytokine profile, producing low but similar levels of IL-4 and IFN-gamma. The discrepancy between high IL-2R expression and low levels of IL-2 protein production by granuloma lymphocytes was associated with increased apoptosis in the granuloma compared with the spleen. These findings support the hypothesis that granulomas may play a role in the regulation of systemic pathology in schistosomiasis by adversely affecting the survival of SEA-reactive, immunopathogenic T lymphocytes.     

Dielectric investigation of the molecular dynamics of blends (II): polymers with dissimilar molecular architecture (PS/TMPC blend)

The molecular dynamics of polystyrene/tetramethyl polycarbonate (PS/TMPC) blends were investigated using dielectric spectroscopy in the frequency and temperature ranges 10^?2?10⁷ Hz and 50–220°C, respectively. Blends with different compositions, namely 12.5, 25, 50, 75 and 87.5 wt% PS/TMPC were found to be compatible over the entire composition range and showed one glass relaxation process corresponding with the transition observed by calorimetric measurements. It was found that neither the kinetics or the distribution of relaxation times of the local process observed in pure TMPC were affected by blending. This fact implies that the local environment of the segments is not changed upon blending. Furthermore, these blends showed that the blending of TMPC with weakly polar polystyrene does not cause any change in the dipolar interaction of the TMPC segments, so that the relaxation strength varies linearly with composition. It is concluded that the polymeric chains of the TMPC and PS are not mixed at a segmental level, but at a higher structural level lying somewhere between segmental and molecular. This conclusion is in good agreement with that obtained in the case of blends composed of polymers with similar molecular architecture.     

Productivity through computer management of a fully automated transportation system

The Morgantown Personal Rapid Transit System is a fully automated, collection and distribution, origin to destination, non-stop transportation system. The system consists of a feet of 73 electrically powered, rubber tired, passenger carrying vehicles, operating on a dedicated guideway network at 15 second headways. The system provides a safe, comfortable non-polluting, reliable means of public transportation between the Central Business District of Morgantown, West Virginia, and the three separated campuses of West Virginia University.

This paper will address the unique application of computers in operating a public transit system which is considered the first of its kind anywhere in the world.     

Artificial neural networks: a novel tool for detecting GMO

Introduction of artificial neural network (ANN) into the field of GMO detection is the aim of this investigation. The usefulness of ANN to predict transgenic maize (Bt-176) based on chemical composition of the extracted crude oil was evaluated. The training set, comprised of a composition of major and minor lipid components as inputs and outputs. Crude oil extracted from the genetically modified maize (Bt-176) and non-transgenic maize was characterized in terms of its fatty acids, phytosterols and tocopherols distribution as well as of its lipid classes and unsaponifiables amounts. The results obtained from lipid distribution analysis showed that the grains of Bt-176 maize were comparable in their composition to that of the control maize. The analytical data have been elaborated by supervised pattern recognition technique ANN in order to classify genetically modified maize (Bt-176) and conventional maize as well as to authenticate the origin of the samples.     

Phenolic extracts of carrot,grape leaf and turmeric powder: antioxidant potential and application in biscuits

Natural antioxidants have gained interest for their role in preventing lipids oxidation. The goals of this investigation were to study the antioxidant potential of carrot (Daucus carota), grape (Vitis vinifera) leaf and turmeric (Curcuma longa) powder extracts and to evaluate their addition as natural antioxidants in biscuits. Physical and chemical properties of biscuit were evaluated during processing and storage. Electrophoretic properties of biscuit dough were carried out to understand the impact of different extracts on the processing of biscuits. Biscuits prepared with 1 % (w/w) grape leaves ethanol (70 %) extract (GLE), carrot aqueous extract (CE), and tumeric aqueous extract (TE) were acceptable. Among extracts, TE was found to retain only 11.2 % activity, wherein GLE had retained 51.0 % activity after baking, which was comparable to butylated hydroxyanisole and better than tert-butylhydroquinone (TBHQ). TBHQ was found to possess the highest activity, followed by GLE, TE and CE, respectively. The ash content of biscuits enriched with TE and GLE was near to that of the control sample. Addition of CE, GLE and TBHQ reduced the force required for breakage. After 15 days of storage, PV was increased in all samples, but in the case of GLE-enriched sample there was a sudden increase in PV from 0.034 to 0.374. Supportive electrophoresis study indicated that there was no change in the protein subunits of biscuit dough fro different samples. It could be concluded that GLE, CE and TE might be used in biscuit baking as natural antioxidants.