Novel Strategy for Synthesis of High Quality CdTe Nanocrystals in Aqueous Solution

A novel aqueous route for the synthesis of high-quality CdTe nanocrystals（NCs） is presented in this article. With both glutathione（GSH） and cysteine[n（GSH）：n（cysteine）=1：3] as stabilizers, high-quality CdTe NCs with controllable photoluminescence（PL） wavelength from 500 to 630 nm can be prepared within 4 h. As-prepared CdTe NCs show higher photoluminescence quantum yields（PLQY） compared with CdTe NCs prepared via other aqueous methods. When the fluorescent emission peak appeared in orange-red window, the PLQY reaches 70% or above at room temperature without any post-preparative treatment.

Mechanism of mine water-inrush through a fault from the floor

The mechanism of mine water inrushes in coal mines in China differs considerably from that in other countries.In China, most water inrushes occur from floor strata, where the water-inrush sources are karstic limestone aquifers.Our study describes the mechanism of mine water inrushes through a fault in the mine floor using principles of strata mechanics and the path of water inrush from an aquifer to the working face.A criterion to judge whether a ground water inrush will occur through a fault or not is also described, together with a case history of water inflow in the Feicheng coalfield, China.

Analysis of photonic crystal fiber sensor character

The special character of a PCF which is used as a gas or liquid sensor is discussed. The field distribution is analyzed when the solid core PCF is injected with different medium that has different relative dielectric constant （or refractive index）. And the experiential formulas of the relation between refractive index of some kinds of liquid and their concentration are given, in order to measure the concentration of the relative liquid. At the same time, the effect of propagation constant on PCF sensor character is also discussed. Furthermore, the photonic medium relative dielectric constant, when it is injected with . band-gap （PBG） of PCF （PBG-PCF） is calculated at different different medium. That is the principle basis for this kind of PCF sensors.

On-line tracking of pulverized coal and biomass fuels through flame spectrum analysis

This paper presents a new approach to the on-line tracking of pulverized coal and biomass fuels through flame spectrum analysis.A flame detector containing four photodiodes is used to derive multiple signals covering a wide spectrum of the flame from visible,near-infrared and mid-infrared spectral bands as well as a part of far-infrared band.Different features are extracted in time and frequency domains to identify the dynamic "fingerprints" of the flame.Fuzzy logic inference techniques are employed to combine typical features together and infer the type of fuel being burnt.Four types of pulverized coal and five types of biomass are burnt on a laboratory-scale combustion test rig.Results obtained demonstrate that this approach is capable of tracking the type of fuel under steady combustion conditions.

Research of variable speed directly driven SRG wind power system position sensorless based on DFNN by FEA

A new method of switched reluctance wind power generation position sensorless based on DFNN by FEA was proposed, Through current and magnetic linkage to get the angle of SRG rotor position, the nonlinear mapping of cur- rent-magnetic linkage-angle was built, By training these sample data from FEA, the angle of SRG rotor position was replaced by the output of DFNN to achieve SRG position sensorless. Simulation results show that the error between actual rotor position and estimate rotor position is small; SRG can commutate with great accuracy; and the output voltage of SRG wind power system under variable wind speed is essentially constant.

Automatic cell object extraction of red tide algae in microscopic images

Extracting the cell objects of red tide algae is the most important step in the construction of an automatic microscopic image recognition system for harmful algal blooms.This paper describes a set of composite methods for the automatic segmentation of cells of red tide algae from microscopic images.Depending on the existence of setae,we classify the common marine red tide algae into non-setae algae species and Chaetoceros,and design segmentation strategies for these two categories according to their morphological characteristics.In view of the varied forms and fuzzy edges of non-setae algae,we propose a new multi-scale detection algorithm for algal cell regions based on border-correlation,and further combine this with morphological operations and an improved GrabCut algorithm to segment single-cell and multicell objects.In this process,similarity detection is introduced to eliminate the pseudo cellular regions.For Chaetoceros,owing to the weak grayscale information of their setae and the low contrast between the setae and background,we propose a cell extraction method based on a gray surface orientation angle model.This method constructs a gray surface vector model,and executes the gray mapping of the orientation angles.The obtained gray values are then reconstructed and linearly stretched.Finally,appropriate morphological processing is conducted to preserve the orientation information and tiny features of the setae.Experimental results demonstrate that the proposed methods can effectively remove noise and accurately extract both categories of algae cell objects possessing a complete shape,regular contour,and clear edge.Compared with other advanced segmentation techniques,our methods are more robust when considering images with different appearances and achieve more satisfactory segmentation effects.

Intrinsic Orientation Effect on the Piezoelectric Response of Multi-domain 0.26Pb(In1/2Nb1/2)O3–0.46Pb(Mg1/3Nb2/3)O3–0.28PbTiO3 Crystals

The crystal intrinsic orientation effect on the piezoelectric response of multi-domain 0.26Pb（Inl/2Nbm）O3-0.46Pb（Mg1/3Nb2/3）O3-0.28PbTiO3 （PIN-PMN-0.28PT） crystals was investigated by coordinate transformation method. The results indicate that crystal intrinsic orientation effect plays a crucial role in determining the piezoelectric properties of multi-domain crystals. Almost 58% and 69% of the transverse piezoelectric coefficients d31 and d32, respectively, and 67% longitudinal piezoelectric coefficient d33 of multi- domain PIN-PMN-0.28PT crystals poled along [011 ]c originate from crystal intrinsic orientation effect. For [001 ]c poled multi-domain PIN-PMN-0.28PT crystals, intrinsic orientation effect contributes to the transverse and longitudinal piezoelectric coefficient at least 79% and 74%, respectively.

Convergence Analysis of Cuckoo Search by Creating Markov Chain

Cuckoo search(CS) has been used successfully for solving global optimization problems.From a theoretical point of view,the convergence of the CS is an important issue.In this paper,convergence analysis of CS was studied.The transition probability characteristics of the population to construct a Markov chain were analyzed.The homogeneity of the Markov chain was derived based on stochastic process theory.Then it was proved to be an absorbing state Markov chain.Consequently,the global convergence of CS was deduced based on conditions of convergence sequence and total probability formula,and the expected convergence time was given.Finally,a series of experiments were conducted.Experimental results were analyzed and it is observed that CS seems to perform better than PSO.

Decoding of QOSTBC Concatenates BCH Code Based on Parallel Interference Cancellation

It has been shown that quasi orthogonal space time block code (QOSTBC) can achieve high transmission rate with partial diversity. In this paper, a QOSTBC concatenating Bose-Chaudhuri-Hocquenghem (BCH) code structure is presented. At the receiver, pairwise detection and error correction are first implemented. The decoded data are regrouped. Parallel interference cancellation (PIC) and dual orthogonal space time block code (OSTBC) decoding are deployed to the regrouped data. The pure concatenated scheme is shown to have higher diversity order and better error performance at high signal-to-noise ratio (SNR) scenario than both QOSTBC and OSTBC schemes. The PIC and dual OSTBC decoding algorithm can further obtain approximate 1.2 dB gains than the pure concatenated scheme at 10-6 bit error probability.

Study on pattern time delay shift coding scheme

Pattern Time Delay Shift Coding (PDS) scheme is robust for underwater acoustic communication. The digital information are encoded in the time delay shift values of the Pattern, so the PDS scheme belongs to the Pulse Position Modulation (PPM). Several Patterns are selected for code division that the communication system could have a high ability to mitigate the inter-symbol interference (ISI) caused by multipath channel. Four communication channels work on the same time divided by different frequency, which lead to 1000bits/s of the data rate of communication. The simulation experiments show that the PDS system could adapt to many underwater acoustic channels for high data rate and high reliability.

Two-phase Method without Any Artificial Variable

A method is provided to achieve an initial basic feasible solution of a linear programming in this paper. This method dose not need introducing any artificial variable, but needs only solving an auxiliary linear programming. Compared with the traditional two-phase method, it has advantages of saving the memories and reducing the computational efforts.