Structural and dielectric behavior of Pb(Mn1/4Zn1/4W1/2)O3 ceramics

Polycrystalline complex perovskite compound of Pb(Mn_1/4Zn_1/4W_1/2)O₃ (PMZW) was prepared from a solid-state reaction technique. X-ray powder diffraction (XRD) study suggests the formation of single-phase compound in orthorhombic structure at room temperature. Dielectric studies as a function of temperature (305–573 K) yielded a small dielectric anomaly at 477 K. Variation of dc resistivity as a function of temperature suggests that the compound behaves as the negative temperature coefficient resistors (NTCR). Proper hysteresis loop could not be observed to confirm the ferroelectric behavior.     

Glycosphingolipids of fetal and adult sheep colonic mucosa

The ganglioside and neutral glycosphingolipid composition of fetal and adult sheep colonic mucosa were characterized and compared. Mono- and tetrahexosylceramide were the major neutral glycolipids of both fetal and adult colons. Adult, but not fetal, mucosa also possessed di- and trihexosylceramide. Similarly, GD_1a, GM₃ and GM₂ were found to be the principal gangliosides in fetal and adult tissue. Adult colonic mucosa possessed significant amounts of GT_1a not present in fetal tissue. Analysis of the hydroxy and nonhydroxyfatty acids as well as of the long chain bases of the major glycosphingolipids revealed differences between these lipophilic components of glycolipids in fetal and adult colonic mucosa. The present results, therefore, indicate that both quantitative and qualitative differences in glycosphingolipid composition exist between fetal and adult sheep colonic mucosa.     

Distribution of glycosphingolipids and ceramide of rat small intestinal mucosa

Previous studies have suggested that glycosphingolipids may be involved in a number of physiological functions of the small intestinal mucosa. Regional variations in many of these processes exist along the length of this organ. In the present studies, the glycosphingolipid and ceramide composition of the proximal, middle and distal thirds of the rat small intestine were characterized and compared. Mono- and trihexosylceramide were the major neutral glycolipids and hematoside (GM₃), the principal ganglioside of this organ. Monohexosylceramide was the major glycolipid of the proximal segment, whereas trihexosylceramide predominated in the distal segments. The total content of neutral glycolipids, ceramide and gangliosides as well as the content of the individual glycosphingolipids and ceramide were highest in the distal segment, intermediate in the middle and lowest in the proximal segment. Additionally, regional variations were noted in the fatty acid composition of the major glycosphingolipids. These differences in the composition of glycolipids and ceramide along the length of the intestine may be responsible, at least partially, for the regional functional specialization seen in this organ.     

Stromal development in the ventral prostate, anterior prostate and seminal vesicle of the rat

The prostate and seminal vesicle (SV) are androgen-dependent secretory glands of the male genital tract. They produce the bulk of the seminal secretions. The object of the present study was to examine and document the ontogeny of stromal maturation in the rat anterior and ventral prostate and SV. These organs have a loosely organized cellular mesenchyme during fetal development. During prostatic development the mesenchyme condensed to form smooth muscle sheaths immediately surrounding the epithelium, with looser connective tissue between individual ducts. In the SV, a loose connective tissue layer called the lamina propria lies between the epithelium and developing muscle. Smooth muscle alpha-actin, myosin, desmin, laminin, vinculin, vimentin and androgen receptor (AR) expression were examined by immunocytochemical methods during the pre- and postnatal developmental periods. The first marker to be detected was vimentin, which was initially found throughout the mesenchyme. During development vimentin became mostly restricted to the interductal tissue of the prostate and the lamina propria of the SV. Smooth muscle markers were expressed in an orderly sequence in a proximal to distal manner along prostatic ducts, from the urethra towards the tips. Expression of alpha-actin was followed by vinculin, myosin, desmin, and laminin. These markers became localized to the developing smooth muscle sheaths and were not expressed in the interductal tissue of the prostate or the lamina propria of the SV. Organ culture experiments demonstrated that androgens were required for the differentiation of smooth muscle sheaths. Castration of adult rats demonstrated that androgens were required to maintain smooth muscle differentiation. In castrates, the stroma was relatively thicker but less dense than in intact animals. Following castration, expression of the smooth muscle markers was lost sequentially in the reverse order of their expression during development. In long-term castrates alpha-actin, vimentin and a small amount of vinculin were detected. AR were first detected in the urogenital sinus mesenchyme immediately surrounding the epithelium at 16 days of gestation. As development progressed expression of AR became more widespread, and postnatally was found throughout the mesenchyme. As maturation of smooth muscle occurred, stromal expression of AR became localized to the muscular sheath immediately surrounding the epithelium. In the prostate the interductal connective tissue displayed very low levels of AR expression. In the SV, AR were also observed in the lamina propria. In summary, stromal differentiation and dedifferentiation in the rat prostate and SV were found to be androgen-dependent processes with ordered sequential ontogenic expression of specific markers.     

Some recent results on the stability of linear time varying systems

Some theorems derived recently by the authors on the stability of multidimensional linear time varying systems are reported in this paper. To begin with, criteria based on Liapunov’s direct method are stated. These are followed by conditions on the asymptotic behaviour and boundedness of solutions. Finally,L ₂ andL ∞ stabilities of these systems are discussed. In conclusion, mention is made of some of the problems in aerospace engineering to which these theorems have been applied.     

An Intelligent Vehicle Highway Information Management System

Abstract: An IVHS (Intelligent Vehicle Highway System) information management system obtains information from road sensors, city maps and event schedules, and generates information to drivers, pafie controllers and researchers. We extend the relational database to model traffic information in a relational database by abstract data types and triggers. Abstract data types are needed for eficient modeling of spatial and temporal information, which create inefficiencies in traditional databases. We use monotonic continuous functions to map the object locations to disk addresses to save disk space and computation time. Model of spatial data is created to efficiently process moving objects. We provide schema for IVHS databases with the relevant abstract data types. We also have a large sample of the relations needed to model IVHS data. Several interesting queries are presented to show the power of the model. Triggers are defined, using rule-definition mechanisms to represent incident detection and warning systems. An eficient physical model with MoBiLe access method is provided.     

直缝钢管埋弧焊焊剂回收方法

分析了直缝钢管埋弧焊接时焊剂输送和回收的几种方式，介绍了焊剂输送回收的主要部件：真空源、除尘器及焊剂分离器等的原理和特点，并提出了较佳的搭配方式。     

Ordered Line Integral Methods for Computing the Quasi-Potential

The quasi-potential is a key function in the Large Deviation Theory. It characterizes the difficulty of the escape from the neighborhood of an attractor of a stochastic non-gradient dynamical system due to the influence of small white noise. It also gives an estimate of the invariant probability distribution in the neighborhood of the attractor up to the exponential order. We present a new family of methods for computing the quasi-potential on a regular mesh named the ordered line integral methods (OLIMs). In comparison with the first proposed quasi-potential finder based on the ordered upwind method (OUM) (Cameron in Phys D Nonlinear Phenom 241:1532–1550, 2012), the new methods are 1.5–4 times faster, can produce error two to three orders of magnitude smaller, and may exhibit faster convergence. Similar to the OUM, OLIMs employ the dynamical programming principle. Contrary to it, they (1) have an optimized strategy for the use of computationally expensive triangle updates leading to a notable speed-up, and (2) directly solve local minimization problems using quadrature rules instead of solving the corresponding Hamilton–Jacobi-type equation by the first order finite difference upwind scheme. The OLIM with the right-hand quadrature rule is equivalent to OUM. The use of higher order quadrature rules in local minimization problems dramatically boosts up the accuracy of OLIMs. We offer a detailed discussion on the origin of numerical errors in OLIMs and propose rules-of-thumb for the choice of the important parameter, the update factor, in the OUM and OLIMs. Our results are supported by extensive numerical tests on two challenging 2D examples.     

PSO Aided Adaptive Complementary Filter for Attitude Estimation

Attitude estimation is one of the core frame- works used for navigating an unmanned aerial vehicle from one place to the other. This paper presents an Euler-based non-linear complementary filter (CF) whose gain parameters are obtained using particle swarm optimization (PSO) technique. It relieves the user from feeding the K _P and K _I parameters manually and adjust these parameters automatically when the error between the attitude measured from accelerometer and the CF increases above a particular threshold. The measurement unit for this research consists of micro-electro-mechanical-systems (MEMS) based low cost tri-axial rate gyros, accelerometers and magnetometers, without resorting to global positioning system (GPS) data. The efficiency of the CF is experimentally investigated with the help of reference attitude and the raw sensor data obtained from commercial inertial measurement unit (IMU). Simulation results based on the test data show that the proposed PSO aided non-linear complementary filter (PNCF) can automatically obtain the required gain parameters and exhibits promising performance for attitude estimation.     

Stock prediction using deep learning

Stock market is considered chaotic, complex, volatile and dynamic. Undoubtedly, its prediction is one of the most challenging tasks in time series forecasting. Moreover existing Artificial Neural Network (ANN) approaches fail to provide encouraging results. Meanwhile advances in machine learning have presented favourable results for speech recognition, image classification and language processing. Methods applied in digital signal processing can be applied to stock data as both are time series. Similarly, learning outcome of this paper can be applied to speech time series data. Deep learning for stock prediction has been introduced in this paper and its performance is evaluated on Google stock price multimedia data (chart) from NASDAQ. The objective of this paper is to demonstrate that deep learning can improve stock market forecasting accuracy. For this, (2D)²PCA + Deep Neural Network (DNN) method is compared with state of the art method 2-Directional 2-Dimensional Principal Component Analysis (2D)²PCA + Radial Basis Function Neural Network (RBFNN). It is found that the proposed method is performing better than the existing method RBFNN with an improved accuracy of 4.8% for Hit Rate with a window size of 20. Also the results of the proposed model are compared with the Recurrent Neural Network (RNN) and it is found that the accuracy for Hit Rate is improved by 15.6%. The correlation coefficient between the actual and predicted return for DNN is 17.1% more than RBFNN and it is 43.4% better than RNN.