Efficient deployment of wireless sensor networks targeting environment monitoring applications

Maximizing network connectivity while maintaining a useful lifetime period without exceeding cost constraints is a challenging design objective for wireless sensor networks. Satisfying such objective becomes even a more intricate task with 3-D setups and harsh operational conditions found in typical large scale environment monitoring applications. While much work has been performed in environment monitoring, only few have addressed the unique characteristics of such applications. In this paper, we introduce a novel 3-D deployment strategy, called Optimized 3-D deployment with Lifetime Constraint (O3DwLC), for relay nodes in environmental applications. The strategy optimizes network connectivity, while guarantying specific network lifetime and limited cost. Key to our contribution is a very limited search space for the optimization problem, in addition to a revised definition for network lifetime that is more appropriate in environment monitoring. The effectiveness of our strategy is validated through extensive simulations and comparisons, assuming practical considerations of signal propagation and connectivity.     

Proteomic Analysis of the Follicular Fluid of Tianzhu White Yak during Diestrus

The aim of this study was to identify differentially expressed proteins in the follicular fluid of Tianzhu white yak during diestrus. Follicles obtained from female yak were divided into four groups according to their diameter: 0–2, 2–4, 4–6 mm, and greater than 6 mm. The follicular fluid was directly aspirated from the follicles and mixed according to follicular size, and two-dimensional gel electrophoresis was carried out on the crude follicular fluid samples. Thirty-four differentially expressed spots were generated from these four sizes of follicles. Fourteen of these spots were analyzed by MALDI-TOF/TOF-MS and identified as: AS3MT, VDP, ANKRD6, C10orf107 protein, MRP4, MAPKAP1, AGO3, profilin-β-actin, SPT2 homolog, AGP, AR, RNF20, obscurin-like-1, and one unnamed protein. These proteins were first reported in follicular fluid, in addition to VDP and AGP. Based on existing knowledge of their function and patterns of expression, we hypothesize that most of these differentially expressed proteins play a role in ovarian follicular growth and development, dominant follicle selection, or follicular atresia and development of oocytes; however, the function of the other differentially expressed proteins in reproduction remains ambiguous.     

Fatigue behavior of RC beams strengthened with prestressed NSM CFRP rods

The fatigue performance of Reinforced Concrete (RC) beams strengthened using NSM CFRP rods was examined in this study. The testing matrix consisted of one un-strengthened beam and four beams strengthened using NSM CFRP rods prestressed to effective strain values of 0, 3260, 6899, and 9177 μ representing 0%, 20.4%, 43.1%, and 57.4% of the CFRP rod ultimate tensile strain, 1.6%. All beams were tested in four-point bending under fatigue conditions representing in-service loading for 3 million cycles at a frequency of 2 Hz. Upper and lower load limits were chosen to induce a stress range of 125 MPa in the tension steel during the first cycle. The fatigue results were compared with experimental test results of identical beams strengthened using prestressed NSM CFRP strips tested under identical fatigue conditions found elsewhere in literature. Test results showed that all strengthened beams experienced deflection increase lower than that of the un-strengthened beam which indicates the efficiency of the strengthening process in reducing the damage accumulation. Also, the percentage deflection increase as well as the stiffness degradation after 3 million cycles are almost the same for all the strengthened beams which indicates that damage accumulation is independent from the prestress level. The groove dimensionality, rather than the CFRP geometry, has a detrimental effect on the bond behavior.     

A flexible nonlinear model predictive control scheme for quality/performance handling in nonlinear SMB chromatography

In this paper, a new state feedback scheme is proposed for the control of simulated moving beds with strongly nonlinear isotherms. The proposed scheme offers a unified framework enabling different performance criteria to be improved according to the active production constraints (achieving low cost, improving efficiency, respecting deadlines) that may unpredictably change during the production batch. The proposed scheme is illustrated through several examples showing the robustness of the closed-loop behavior against parameter uncertainties as well as its reactivity to changes in the active auxiliary criterion.     

Probing a Device's Active Atoms

Materials science and device studies have, when implemented jointly as “operando” studies, better revealed the causal link between the properties of the device's materials and its operation, with applications ranging from gas sensing to information and energy technologies. Here, as a further step that maximizes this causal link, the paper focuses on the electronic properties of those atoms that drive a device's operation by using it to read out the materials property. It is demonstrated how this method can reveal insight into the operation of a macroscale, industrial‐grade microelectronic device on the atomic level. A magnetic tunnel junction's (MTJ's) current, which involves charge transport across different atomic species and interfaces, is measured while these atoms absorb soft X‐rays with synchrotron‐grade brilliance. X‐ray absorption is found to affect magnetotransport when the photon energy and linear polarization are tuned to excite Fe? O bonds parallel to the MTJ's interfaces. This explicit link between the device's spintronic performance and these Fe? O bonds, although predicted, challenges conventional wisdom on their detrimental spintronic impact. The technique opens interdisciplinary possibilities to directly probe the role of different atomic species on device operation, and shall considerably simplify the materials science iterations within device research.     

Diffusion analysis and modeling of kinetic behavior for treatment of brine water using electrodialysis process

In this study, the removal of monovalent and divalent cations, Na⁺, K⁺, Mg²⁺, and Ca²⁺, in a diluted solution from Chott-El Jerid Lake, Tunisia, was investigated with the electrodialysis technique. The process was tested using two cation-exchange membranes: sulfonated polyether sulfone cross-linked with 10% hexamethylenediamine (HEXCl) and sulfonated polyether sulfone grafted with octylamine (S-PESOS). The commercially available membrane Nafion® was used for comparison. The results showed that Nafion® and S-PESOS membranes had similar removal behaviors, and the investigated cations were ranked in the following descending order in terms of their demineralization rates: Na⁺ > Ca²⁺ > Mg²⁺ > K⁺. Divalent cations were more effectively removed by HEXCl than by monovalent cations. The plots based on the Weber–Morris model showed a strong linearity. This reveals that intra-particle diffusion was not the removal rate-determining step, and the removal process was controlled by two or more concurrent mechanisms. The Boyd plots did not pass through their origin, and the sole controlling step was determined by film-diffusion resistance, especially after a long period of electrodialysis. Additionally, a semi-empirical model was established to simulate the temporal variation of the treatment process, and the physical significance and values of model parameters were compared for the three membranes. The findings of this study indicate that HEXCl and S-PESOS membranes can be efficiently utilized for water softening, especially when effluents are highly loaded with calcium and magnesium ions.     

Classical plasticity and viscoplasticity models reformulated: theoretical basis and numerical implementation

The well-known phenomenological model of small strain rate-independent plasticity is reformulated in this paper. The main difference from the classical expositions concerns the absence of the plastic strain from the list of state variables. We show that with the proposed choice of state variables, including the total and the elastic strains and strain-like variables which control hardening, we recover all the ingredients of the classical model from a minimum number of hypotheses: instantaneous elastic response and the principle of maximum plastic dissipation. We also show that using a regularized, penalty-like form of the principle of maximum plastic dissipation, we can recover the classical viscoplasticity model. As opposed to the previous schemes used for the finite element implementation of this model (e.g. B-bar method), we propose an approach in which the basic set of equations need not be modified. The operator split method is used to simplify the details of the numerical implementation concerning both the computation of state variables and the incompatible mode based finite element approximations. The latter proves to be indispensable for accommodating the near-incompressible deformation patterns arising in the classical plasticity. An extensive set of numerical simulations is used to illustrate the proposed formulation. © 1998 John Wiley & Sons, Ltd.     

Phe496 and Leu497 are essential for receptor binding and cytotoxic action of the murine interleukin-4 receptor targeted fusion toxin DAB389-mIL-4

DAB₃₈₉-mIL-4 is a murine interleukin-4 (mIL-4) diphtheria toxin-relatedfusion protein which has been shown to be selectively toxicto cells expressing the mIL-4 receptor. In this report, we haveused site-directed and in-frame deletion mutagenesis to studythe role of the putative C-terminal -helix (helix E) of themIL-4 component of DAB₃₈₉-mIL-4 in the intoxication process.We demonstrate that deletion of the C-terminal 15 amino acidsof the fusion toxin leads to loss of cytotoxicity. The substitutionof Phe496 with either Pro, Ala or Tyr, results in a > 20-folddecrease in cytotoxic activity of the respective mutant fusiontoxins. In addition, substitution of Leu497 with either Alaor Glu results in a similar loss of cytotoxic activity. Allof these mutant forms of the mIL-4 fusion toxin demonstratea significant decrease in binding affinity (K_i) to the mIL-4receptor in a competitive radioligand binding assay. In markedcontrast, however, the substitution of Asp495 with Asn resultsin a 4-fold increase in cytotoxic potency and binding affinityto mIL-4 receptor bearing cells in vitro.     

Object Pose: The Link between Weak Perspective,Paraperspective, and Full Perspective

Recently, DeMenthon and Davis (1992, 1995) proposed a method for determining the pose of a 3-D object with respect to a camera from 3-D to 2-D point correspondences. The method consists of iteratively improving the pose computed with a weak perspective camera model to converge, at the limit, to a pose estimation computed with a perspective camera model. In this paper we give an algebraic derivation of DeMenthon and Davis' method and we show that it belongs to a larger class of methods where the perspective camera model is approximated either at zero order (weak perspective) or first order (paraperspective). We describe in detail an iterative paraperspective pose computation method for both non coplanar and coplanar object points. We analyse the convergence of these methods and we conclude that the iterative paraperspective method (proposed in this paper) has better convergence properties than the iterative weak perspective method. We introduce a simple way of taking into account the orthogonality constraint associated with the rotation matrix. We analyse the sensitivity to camera calibration errors and we define the optimal experimental setup with respect to imprecise camera calibration. We compare the results obtained with this method and with a non-linear optimization method.     

Effect of antimicrobial agents and dough conditioners on the shelf-life extension and quality of flat bread, as determined by near-infrared spectroscopy

Middle Eastern Countries are experiencing the emergence of high volume production and retail marketing over traditional unit baking and retailing. This phenomenon has revealed a shortcoming in quality issues in Arabic flat bread (AFB) manufacture. Therefore, shelf-life extension and quality improvement are in demand to limit economic loss. Five improvers and a control (without any improver) were selected for improving shelf-life and quality of AFB. The improver treatments included: (1) sodium 9 stearoyl-2-lactylate (SSL), (2) monoglycreides (MG), (3) hydroxy propyl methyl cellulose gum (HPMC), (4) high-fructose corn syrup (HFCS), and (5) a combination of all the aforementioned improvers. The texture analysis data indicated that the presence of HFCS may act as a plasticizer through contributing to the longer tearing time. The other treatments exhibited a significant decline in tearing time throughout storage. The NIRS data indicated that after 3 days, the control was less fresh than AFB formulated with HFCS or improver combinations. The sensory evaluation of AFB exhibited that the improver combination significantly improved the quality attributes.