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In recent years, the methods on matrix-based or bilinear discriminant analysis (BLDA) have received much attention. Despite their advantages, it has been reported that the traditional vector-based regularized LDA (RLDA) is still quite competitive and could outperform BLDA on some benchmark datasets. Nevertheless, it is also noted that this finding is mainly limited to image data. In this paper, we propose regularized BLDA (RBLDA) and further explore the comparison between RLDA and RBLDA on another type of matrix data, namely multivariate time series (MTS). Unlike image data, MTS typically consists of multiple variables measured at different time points. Although many methods for MTS data classification exist within the literature, there is relatively little work in exploring the matrix data structure of MTS data. Moreover, the existing BLDA can not be performed when one of its within-class matrices is singular. To address the two problems, we propose RBLDA for MTS data classification, where each of the two within-class matrices is regularized via one parameter. We develop an efficient implementation of RBLDA and an efficient model selection algorithm with which the cross validation procedure for RBLDA can be performed efficiently. Experiments on a number of real MTS data sets are conducted to evaluate the proposed algorithm and compare RBLDA with several closely related methods, including RLDA and BLDA. The results reveal that RBLDA achieves the best overall recognition performance and the proposed model selection algorithm is efficient; Moreover, RBLDA can produce better visualization of MTS data than RLDA., 14 pages, 2 figures

The Bayesian information criterion (BIC), defined as the observed data log likelihood minus a penalty term based on the sample size $N$, is a popular model selection criterion for factor analysis with complete data. This definition has also been suggested for incomplete data. However, the penalty term based on the `complete' sample size $N$ is the same no matter whether in a complete or incomplete data case. For incomplete data, there are often only $N_i, Comment: 16 pages, 4 figures

The poisoning effects of KCl and As2O3 on selective catalytic reduction (SCR) of NH3 with NO over Mn-Ce/AC catalysts were investigated with the reaction temperature range of 100–250 °C. KCl and As2O3 poisoned catalysts were synthesized by impregnation method and catalytic activity test was performed under the condition of simulated flue gas. The changes of crystal structure, microstructure, surface atomic state, surface acidity and functional groups were characterized by XRD, SEM, BET, XPS, NH3-TPD and FT-IR. Deactivation for single KCl or As2O3 doping catalyst was observed and severe synergistic inactivation occurred with the common effect of KCl and As2O3 on the catalyst. KCl destroyed the porosity of active carbon (AC) and could react with OH and C O on the surface of AC to ultimately form -O-K and Cl-C-O-K, resulting in the decrease of NH3 and NO adsorption. Besides, KCl caused the reduction of oxygen vacancies and chemisorbed oxygen on the Mn-Ce/AC catalyst. Lattice oxygen of MnOx may be transformed to surface chemisorbed oxygen to oxidize As2O3. As2O3 was oxidized to As2O5 and some layer was formed on the surface of catalyst preventing NH3 and NO adsorption. In addition, As2O3 could increase the number of oxygen vacancies and decrease the surface acidity of Mn-Ce/AC catalyst. According to the experimental results and theoretical analysis, the synergy poisoning model of KCl and As2O3 on Mn-Ce/AC catalysts was schematically established.

In this paper, channel spatial characteristics which mainly depend on the spatial correlation are selected as the significant factors in over-the-air (OTA) testing for multiple input multiple output (MIMO) devices. The multi-probe anechoic chamber method, a promising candidate of the MIMO OTA testing methods, can reproduce the multipath environments in a controllable manner. A novel physical configuration based on the variation of relative positions of probes in a MIMO OTA setup is put forward to obtain better spatial characteristics. Two physical configurations are presented to make a comparison with the typical configuration in this paper. The simulation results show that by making a proper probe configuration, good channel simulation accuracy can be achieved. Meanwhile, in order to get better performance of emulating channel spatial characteristics, probes in the first and the last probe rings should be placed symmetrically in three dimensional (3D) physical probe configuration.

This paper proposes a low-cost hardware architecture based on concurrent dual-band digital pre-distorter (DPD). The architecture is implemented on field programmable gate array (FPGA) to compensate for the nonlinearity of the concurrent dual-band power amplifier (PA). This implementation introduces a novel model complexity reduction technique into system, namely, time-division multiplexing for out-of-band lookup tables (LUTs) sharing. Performances are evaluated with an experimental test setup using a wideband class-F PA. The dual-band signal center frequency separated by 80 MHz. Lower and upper center frequency are located at 2.61 GHz and 2.69 GHz, respectively. This novel DPD implementation maintains excellent performance, but uses hardware resources reduced by 29.17% compared with conventional approaches. The results show that the adjacent channel power ratio (ACPR) is less than 59 dBc and normalized mean square error (NMSE) is around 62dB for lower sideband (LSB) and 63dB for upper sideband (USB).

This paper studies the behaviors of power amplifier (PA) driven by a single-carrier continuous wave (CW) signal and a two-carrier CW signal both in theory and simulation, and explains why the traditional dual-band PA failed to perform satisfactory results when a two-carrier CW signal is applied to, called concurrently. Besides that, an evaluation standard of concurrent dual-band PA was presented to value its performance. Solution was given with design and fabrication of a concurrent 1.85 GHz/2.65 GHz class F PA, employing a 10W GaN HEMT device from Cree, CGH40010, whose measurement shows the saturated output power is 40.6 dBm and 40.8dBm with drain efficiencies (DE) of 77.4% and 75.3% at 1.85 GHz and 2.65 GHz, respectively. On the other hand, we see that the peak DE achieves 59.7% with an output power of 39.9 dBm in concurrent mode, which follows up with the standard.

A new compact bandpass filter based on two meandered parallel-coupled lines of different lengths in shunt is presented, using the signal-interference technique, this filter obtains a low insertion loss and sharp rejection. A set of analytical formulas and guidelines for the design of the bandpass filter are provided in two theoretical analysis methods. According to the number of attenuation poles of the reflection coefficients in the passband, it can be summed up two types of filters. To validated this topology, two wideband bandpass filters centered at 3 GHz are built to verify the theoretical prediction, the measured frequency response of the filter agrees excellently with the predicted result.

A triangular memory polynomial (TMP) predistorter is presented in this paper to linearize a power amplifier's nonlinear with memory effects. Compared with the traditional memory polynomial (MP) predistorter, the coefficients of TMP predistorter is reduced more than 75%, which can effectively decrease the implementation complexity. The coefficients of predistorter are directly extracted from an offline system identification process by an open-loop structure in our approach. Several signals with data rate 5 MHz, 10 MHz, 15 MHz and 20 MHz are used to verify the performance of the proposed predistorter. Experimental results show that the proposed TMP predistorter and the traditional MP predistorter almost have the same performance.

In this paper, a novel design of planar dual-band multi-way lossless power dividers (PDs), namely Bagley Polygon PDs, is presented. The proposed PDs use Π-type dual-band transformers as basic elements, whose design formulas are analyzed and simplified to a concise form. The equivalent circuit of the dual-band Bagley Polygon PD is established, based on which design equations are derived mathematically. After that, the design procedure is demonstrated, and special cases are discussed. To verify the validity of the proposed design, 3-way and 5-way examples are simulated and fabricated at two IMT-Advanced bands of 1.8GHz and 3.5GHz, then simulation and measurement results are provided. The presented PDs have good performances on the bandwidths and phase shifts. Furthermore, the planar configuration leads to convenient design procedure and easy fabrication.

The complete mitogenome sequence of Eurasian water shrew (Neomys fodiens) was determined using long PCR. The genome was 17,260 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 control region. The overall base composition of the heavy strand is A (33.0%), C (23.2%), T (30.9%) and G (12.9%). The base compositions present clearly the A–T skew, which is most obviously in the control region and protein-coding genes. The extended termination-associated sequence domain, the central conserved domain and the conserved sequence block domain are defined in the mitochondrial genome control region of Eurasian water shrew. Mitochondrial genomes analyses based on MP, ML, NJ and Bayesian analyses yielded identical phylogenetic trees. Neomys elegans, Soriculus fumidus, and N. fodiens formed a monophyletic group with the high bootstrap value (100%) in all examinations. This clade with the Anourosorex squamipes as the sister taxon to Sorex.

The high-directivity single- and dual-band directional couplers based on substrate integrated coaxial line (SICL) are first proposed in this paper. As the SICL features the propagation of TEM mode, the SICL directional coupler can keep its high-directivity compared with the microstrip one. The SICL coupler also characterizes a vias-shielded structure keeping it away from lateral leakage, cross-talk or unwanted parallel-plate mode. The design approaches of the single- and dual-band SICL couplers with proper width-spacing are given. Experiments are carried on a SICL 2.35 GHz coupler and a SICL 0.8/2.35 GHz coupler. Compared with microstrip couplers, the SICL ones show a great enhancement in directivity.

Horizontal well technology is very effective to enhance oil production rate of single well in heavy oil reservoirs because of its large oil drainage area compared with vertical wells. However, since the influence of steam injection parameters and reservoir heterogeneity, length of steam absorption section in thermal horizontal wells is only 50m~70m by using conventional steam injection pipe string. Nowadays, length of completion section in thermal horizontal wells is generally about 200m, therefore controlled reserves in 130m~150m horizontal section can't be effectively produced by using conventional steam injection technology. In order to improve recovery effect of thermal horizontal wells, adaptive uniform steam injection technology is developed in Shengli oilfield. Based on studying and designing adaptive uniform flow regulator, steam injection parameters, number and arrangement of adaptive uniform flow regulators are optimized according to steam equipment capacity and reservoir properties, thus realizing uniform steam absorption in long horizontal sections. Reservoirs of whole horizontal section in thermal horizontal wells can be effectively produced and producing degree of controlled reserves in horizontal wells can be increased. Not only oil recovery rate of thermal horizontal wells is enhanced, but also oil recovery ratio.

In order to communicate successfully for mobile stations in signal dead zone, this paper presents an inverse-gain- feedback dual-loop automatic gain control (AGC) circuit used in WCDMA repeater uplink system. The repeater employs two stages radio frequency AGC circuits, which are gain control of input part and output part respectively, so that the system can work normally and automatically control the output power. Agilent advanced design system (ADS) is used as a simulation tool to analyze the performance. The results show that it is performed well, which has the characteristic of good frequency selectivity and channel selectivity, steady controllable output, large range of AGC gain and wide range of output power. Therefore, the proposed system is suitable to solve the problem of the dead zone in WCDMA communication.

In this paper the finite-difference time-domain (FDTD) method and the transmission lines (TL) method are used respectively in the calculation of voltage standing wave ratio (VSWR) in an axisymmetric coaxial connector with nonuniform medium. Numerical results between the two methods are compared; more details of signal propagation in the connector can be given from the FDTD method, but the TL theory used is more simple and satisfactory results can also be obtained; the experimental result is in agreement with the calculations.

In this paper crosstalk between transmission lines. (TL) in special directions such as perpendicular and parallel is studied in the frequency domain and time domain via electromagnetic field (EMF) theory. Magnitude of crosstalk between the two states is compared. Regulations of when the peaks or troughs should occur are summarized, results are verified with that of the finite-difference time-domain (FDTD) method.