Detecting removed attributes in the cyber system for smart manufacturing

The Journal of Supercomputing - According to the concept of edge computing, some service and data should be moved from the centralized data server to the data source for enhancing the computational...     

Rapid fabrication of organic/organic photonic bandgap films with tuneable mechanical properties using blended polymer spheres

In this study, the photonic bandgap (PBG) film with tunable mechanical properties and photonic stop band was prepared by a simple and feasible approach. Colloid polymer spheres with a relatively large diameter (approximate D_n of 200 nm) and different glass transition temperatures (T_g) were blended with small polystyrene (PS) latex (D_n = 20 nm) and were subsequently casted on a substrate for 3 h at 50°C for self‐assembly of the PBG film. The monodispersed polymer spheres were synthesized by soap‐free emulsion polymerization in the boiling state. The T_g values of the spheres were predetermined based on the Fox equation, and designed to fall in the region of ?34°C to 112°C. Small PS could also be synthesized by this approach using the comonomer, sodium p‐styrenesulfonate (NaSS), to ensure the small diameter. The long‐range ordered structure constructed by embedding the small PS in the PBG film was indirectly confirmed on the basis of SEM analysis, from which the monochromatic film color was determined based on Bragg's diffraction law. Tunable film color was achieved by adjusting the diameter of the spheres, as evaluated using UV–Vis. Tunable mechanical properties of the PBG film were also achieved by varying the T_g of the spheres or the filling ratio of small PS. Based on these approaches, the ultimate tensile strength could be tuned in the region between 0.39 to 4.7 Mpa, and the relative strain could be varied from 1236% to 16%, illustrative of the excellent deformability of the film. Furthermore, by variation of these two parameters, the film properties could be changed from typical elastomer behavior to brittle plastic polymer type behavior, greatly extending the prospective application fields. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40276.     

Boron‐ and nitrogen‐doped penta‐graphene as a promising material for hydrogen storage: A computational study

We fulfill a comprehensive study based on density functional theory (DFT) computations to cast insight into the dissociation mechanism of hydrogen molecule on pristine, B‐, and N‐doped penta‐graphene. The doping effect has been also illustrated by varying the concentration of dopant from 4.2 at% (one doping atom in 24 host atoms) to 8.3 at% (two doping atoms in 24 host atoms) and by contemplating different doping sites. Our theoretical investigation shows that the adsorption energy of H₂ molecule and H atom on the substrate can be substantially enhanced by incorporating boron or nitrogen into penta‐graphene sheet. The B‐ and N‐doped penta‐graphene can effectively decompose H₂ molecule into two H atoms. Our results demonstrate that activation energies for H₂ dissociation and H diffusion on the B‐ and N‐doped penta‐graphene are much smaller than the pristine penta‐graphene. Further investigation of increasing concentration dopants of the penta‐graphene sheet gives sufficiently low activation barrier for H₂ dissociation process. This investigation reveals that the boron and nitrogen dopants can act as effective active site for H₂ dissociation and storage.     

Applying likelihood on Hopfield neural network for radar tracking

Abstract

The multiple‐target tracking (MTT) algorithm plays an important role in radar systems. Data association is the most important technique to solve the tracking problems associating dense measurements with existing tracks. A new approach applying Likelihood to measurements and existing tracks in a radar system based on Neural Network computation is investigated in this paper. The proposed algorithm will solve both the data association and the target tracking problems simultaneously. With this approach, the matching between radar measurements and existing target tracks can achieve global relevance. Computer simulation results indicate the ability of this algorithm to keep track of targets under various conditions.     

Solving optimization problems by searching along a curve

Abstract

This paper proposes a curve for the one‐dimensional search method in optimization problems. The search is along a curve instead of a line. This curve is determined by a parameter [u] from the following three points: (1) the initial point X_o, (2) the Cauchy point X_c, (3) the Newton point X_N, and has the following four characteristics: (1) tangents to the steepest descent direction at X_o, (2) passes through X_N, (3) decreases monotonically from X_o to X_N for a quadratic function, (4) no complex computation on the parameter u. Therefore, the proposed method has the following advantages: (1) it is globally convergent, (2) it is locally q‐quadratically (or q‐superlinearly for quasi‐Newton point) convergent, (3) the search procedure is as simple as the line search method.     

Decomposition of singular large sparse matrix by adding dummy links and dummy degrees

Abstract

This paper proposes a simple scheme to decompose an n×n nonpositive definite matrix, A, associated with simultaneous equations, A X = B, into a triple‐factors (lower triangular, diagonal, and upper triangular matrices), i.e., Å = L D U, without interchanging rows or columns of A, but with A expanded with new rows and new columns to an m×m matrix Å. Whenever a near‐zero diagonal element, say ā_ii , is encountered and used as a pivoting element, an appropriate positive real number, say p, is added to this diagonal element, and a new term —px_k is also added to the i‐th equation, where x_k is a new variable called “dummy variable'’. If we also add a new equation —px_i + px_k = 0 to enforce the new added variable x_k equal to x_i then the modified i‐th equation has the same effect as the original equation. Therefore, the original solution X can be found directly from the expanded solution of the modified expanded equation. The method is very useful in solving the following problems: (1) nonlinear problems near the limit state, (2) postbuckling analysis, (3) system equations with constraint conditions, and (4) getting eigenvectors from eigenvalues.     

Continuous photodetection of resonance fluorescence

Abstract

The concept of photodetection as a continuous quantum measurement introduced by Srinivas and Davies is extended to the detection of resonance fluorescence. This is a new approach to an old subject. This is also a new development in continuous photodetection in the sense that a fermion rather than the traditional boson field is the subject of monitoring. The superoperators for the no-count and the one-count processes are postulated, following the examples of Srinivas and Davies. The probability for the m-count process is then derived on the basis of these postulates. The first two factorial moments of the photon-number distribution are calculated, which are then used to evaluate the non-classical effects in resonance fluorescence. A parameter slightly different from Mandel's is found to be more suitable indicator of photon antibunching in the transient state.     

A two‐parameter quasi‐linear model for gauged river basins

Abstract

Two rainfall intensity dependent parameters are incorporated into a quasi‐linear representation of the outflow to analyze the hydro‐logic response problems of a gauged river basin.

The model is employed to generate the unit hydrographs of a (non‐linear) small basin due to different rainfall inputs, to exhibit the storage‐discharge relation in a medium basin due to a single storm event, and to synthesize the rainfall‐runoff process in two large river basins due to storm events at different times. In all three cases, the analytical results from the model compare nicely with the experimental observations.