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In contrast to the conventional monofacial photovoltaic (PV) modules, bifacial PV modules yield more electrical energy by utilizing the reflected or scattered light from the ground and surroundings. The energy generation efficiency of bifacial modules is determined by both the front-side and the rear-side output power. In this study, we compared the IV parameters as well as field performance of different module structures to further realize the influencing factors dominating the energy gain of bifacial modules. Our results show that the glass/glass bifacial modules encapsulated with bifacial solar cells provide over 6% more energy yield compared to the glass/backsheet monofacial modules encapsulated with regular monofacial solar cells. Due to optical enhanced effects of a reflective coating on the rear glass, the energy yield gain of bifacial modules can be increased to above 10%, even though the bifaciality factors were reduced from 72% to 64%. Our study indicates that enhancing the front-side output power of bifacial modules produces more benefits.

The present paper reports Cu and Cu(Mn) films prepared layer-by-layer using an electrochemical atomic layer deposition (ECALD) method. The structure and properties of the films were investigated to elucidate their suitability as Cu interconnects for microelectronics. Previous studies have used primarily a vacuum-based atomic layer deposition to form a Cu metallized film. Herein, an entirely wet chemical process was used to fabricate a Cu film using the ECALD process by combining underpotential deposition (UPD) and surface-limited redox replacement (SLRR). The experimental results indicated that an inadequate UPD of Pb affected the subsequent SLRR of Cu and lead to the formation of PbSO 4 . A mechanism is proposed to explain the results. Layer-by-layer deposition of Cu(Mn) films was successfully performed by alternating the deposition cycle-ratios of SLRR-Cu and UPD-Mn. The proposed self-limiting growth method offers a layer-by-layer wet chemistry-based deposition capability for fabricating Cu interconnects.

This paper is concerned with the optimal linear filtering problem for systems with incomplete measurements and white multiplicative noises. The measurement data suffers from one-step delay and packet dropouts in transmission from the sensor to the filter. At each moment, the filter may receive one or two data packets or nothing. First, the multiplicative noises are transferred to the additive noises. Then, a new augmented state vector with a lower order is proposed. Based on the new state vector, the optimal linear filter is obtained. Moreover, the steady-state behavior of the proposed filter is studied.

The hydrodynamic problem of oblique impact of a water cone on a solid wall is investigated by the three dimensional (3D) velocity potential flow theory. The time stepping method is used in a stretched coordinate system to track the moving water surface where the fully nonlinear dynamic and kinematic boundary conditions are satisfied through an improved Eulerian method. In particular the free surface elevation and potential variation are updated at a given azimuth in each θ plane of the cylindrical coordinate system, to overcome the numerical difficulties caused by the complex variation of the 3D curved free surface. Remeshing and smoothing are applied regularly along the intersection lines of the free surface and each θ plane. Detailed convergence study with respect to a time step and element size has been undertaken and high accuracy has been achieved. Extensive simulations are made for perpendicular and oblique impacts. Detailed results for pressure and free surface profile are provided.

This paper is concerned with the optimal estimation problem for discrete-time stochastic linear systems with finite consecutive packet dropouts. By introducing a set of new variables, a state augmented system with a lower order is obtained. Based on the new model, the optimal estimators including filter, predictor and smoother are readily solved in the least-mean-square sense via the innovation analysis approach. The solutions depend on the recursion of a Riccati equation and a Lyapunov equation. The steady-state estimators have also been investigated. A sufficient condition for the convergence of the optimal estimators has been given. A simulation shows the effectiveness of the proposed algorithms.

Owing to the growing size of the eigenvalue problem and the growing number of eigenvalues desired, solution methods of iterative nature are becoming more popular than ever, which however suffer from low efficiency and lack of proper convergence criteria. In this paper, three efficient iterative eigenvalue algorithms are considered, i.e., subspace iteration method, iterative Ritz vector method and iterative Lanczos method based on the cell sparse fast solver and loop-unrolling. They are examined under the mode error criterion, i.e., the ratio of the out-of-balance nodal forces and the maximum elastic nodal point forces. Averagely speaking, the iterative Ritz vector method is the most efficient one among the three. Based on the mode error convergence criteria, the eigenvalue solvers are shown to be more stable than those based on eigenvalues only. Compared with ANSYS`s subspace iteration and block Lanczos approaches, the subspace iteration presented here appears to be more efficient, while the Lanczos approach has roughly equal efficiency. The methods proposed are robust and efficient. Large size tests show that the improvement in terms of CPU time and storage is tremendous. Also reported is an aggressive shifting technique for the subspace iteration method, based on the mode error convergence criteria. A backward technique is introduced when the shift is not located in the right region. The efficiency of such a technique was demonstrated in the numerical tests.

The functional strain Fhhh, constructed with the protoplast fusion technique, was applied to PTA wastewater treatment at a NJYZ pilot plant. The maximum chemical oxygen demand (COD) removal efficiency and effluent suspended solids obtained were 97% and 59 mg L−1, respectively, at a hydraulic retention time of 1.3 days and an F/M rate of 1.35 g COD g SS−1 day−1. The specific degradation rate arrived at 1.31 day−1 in the bioreactor after a 180-day operation, which is much higher than corresponding data of other related references. The addition of Mn2+, Cu2+, Zn2+, and SeO3 2− significantly stimulated the MnP exprssion, and a positive correlation was established between the improvement of MnP expression and the removal efficiencies of COD, tereogtgaleuc acid, p-toluic acid, and 4-carboxybenzaldehyde in purified terephthalic acid wastewater. The effluent water quality was also improved significantly as long as the COD:TN:TP ratio was optimally maintained around 100:1.16:0.22; the best growth and flocculation ...

In contrast to the weak interaction commonly found between low valence metals such as Ca and a polymeric material, considerable changes in photoelectron spectroscopy have recently been observed in experiment after evaporating Ca onto poly (9,9-dioctylfluorene) (PFO). Here, by performing calculations using Moller–Plesset perturbation theory, we show that the Ca/PFO interaction depends on the number of Ca atoms attaching to the PFO oligomer unit. A strong interaction could take place when two Ca atoms were adsorbed at a PFO unit. Further, the resulted PFO deformation and the modified frontier orbitals could be recovered when oxygen was further added.

A new US law allows warrantless wiretapping whenever one end of the communication is believed to be outside national borders. This creates serious security risks: danger of exploitation of the system by unauthorized users, danger of criminal misuse by trusted insiders, and danger of misuse by government agents.

The slow-wave phenomena and the pulse distortions in optically excited Schottky-contacted coplanar waveguides are analyzed in this paper. The localized excitation model presented is formulated by the combination of the original and frequency-dependent versions of the FDTD method. Some attractive physical properties of Schottky-contacted CPW under optical illumination are examined. >

In the area of high-performance computation, direct methods for solving large systems of equations on distributed memory machines is one very important issue. In general, there are two ways to improve the computational efficiency of the solution procedure. One is to increase the sequential efficiency by maximizing vector operations and/or using other techniques, such as unrolling. The other is to decrease the communication cost across processors. Conventionally, the pure JIK form of LDLT factorization algorithms based on the column skyline storage scheme lead to natural synchronization, i.e., starting a step, all but one processor waits for the result of a particular processor for the j-th column or j-th block. Carefully rearranging the communication order, this paper proposes a mixed JIK form with one-step overshoot for sending and receiving. Associated with asynchronous communication, the mixed asynchronous approach can greatly reduce the processor idling time and enhance therefore the performance of parallel computation. Several practical examples show the efficiency of this approach.

With quantum chemical PM3/FF method, effects of strucure and substituents -NO 2 and -NH 2 on nonlinear optical properties of polypyridinopyridine(PPY) were discussed. The results showed that the β and y values were -5.54 x 10 -29 esu and -1.544 x 10 -32 esu, respectively. In three stable structures of equal-bond length structure (a), cis-structure (b) and trans-structure (c), the β and y values of (a) and (c) is larger than (b). More specially, β and y values of (c) increased promptly as the number of repeat unit increased. When the number of unit was over four, (c) gave the biggest β and y. In structures of PPY substituted by NO 2 and NH 2 , the effects of pull-push electron and π-electron delocalization became stronger, β increased effectively to about 1.6 x 10 -27 esu. PPY is a promising candidate of nonlinear optical (NLO) materials.

Low frequency electroacupuncture (EA) analgesia has been thought to be mediated by endogenous opioids. Among other lines of evidence, it has been reported that EA stimulation delivered at 2 and 2-15 Hz in rats could be blocked or partially antagonized by naloxone (NAL) and naltrexone (NTX). In contrast, experiments in one of our laboratories (D.J.M.) showed that NAL did not inhibit 2 Hz, and even potentiated 125 Hz EA analgesia. In an attempt to resolve these discrepancies, we conducted joint experiments in the U.S.A. and in China using the methods which previously yielded NAL reversibility of EA analgesia. In no experiment did opiate antagonists block or reduce EA analgesia. On the contrary, we found that, in most experiments, NAL and NTX potentiated 2 and 2-15 Hz EA analgesia respectively. The potentiation occurred independently of laboratory methods, geographic location of the experiment, strain (Chinese or American), tail temperature, sex, and weight of rats. This potentiation suggests the existence of an opioid anti-analgesic system or that NAL and NTX acquired analgesic properties following EA. These results indicate that EA analgesia in rats is a variable phenomenon even when laboratory methods are rigorously replicated. The EA stimulation may activate multiple conflicting neural circuits which interact and ultimately modulate the analgesic outcome.