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With a quartz crystal resonator as the core element, the quartz crystal microbalance (QCM) has been an important sensor for various samples including chemical, biomedical, gas, and liquid with broad applications. The sensing mechanism of QCM is based on the gravimetric effect of samples on vibration frequency of the quartz crystal blank. For accuracy and sensitivity, it is important to have a better estimation of the vibration frequency with the consideration of quartz crystal material, configuration, electrodes, mounting, absorption layer, among other factors. As a result, a thorough study of vibrations of the quartz crystal plate is vital for a good design of the QCM and fabrication processing.

Power supply capability (PSC) is a significant index to evaluate the operation state of distribution systems. The PSC is similar to total transfer capability (TTC) of transmission system. However, the model of TTC cannot be utilized to calculate PSC because of their different constraints. The buses load increasing ratio is not considered in traditional maximum multiple method since an effective load increasing strategy is not available. This paper proposes a novel model and analytical method to calculate PSC in which the sensitivity of power flow and bus voltage is considered. In high voltage (HV) distribution networks, the DC power flow model is introduced to calculate the sensitivity of power flow distribution. And the Jacobian matrix is used to obtain the sensitivity of bus voltage. The results of sensitivity analysis are utilized to obtain the effective bus set (EBS) to increase load efficiently in every iteration. The validity of proposed model and method is demonstrated on IEEE 33-bus distribution system. By comparing the results with the conventional method, the proposed method proves more effective and accurate in HV distribution networks.

Ant Colony Algorithm has some advantages in solving complex optimization problems, in particular discrete optimization problem. A mine locomotive scheduling algorithm based on the improved Ant Colony Algorithm for the mine locomotive scheduling problem has proposed in this paper. The method takes simulated annealing algorithm as a local search strategy of ant colony algorithm, aim at expanding the solution search space, avoiding falling into local optimum that improve convergence rate of the algorithm by dynamic pheromone evaporation factor. Simulation results show that the algorithm is more efficiency in locomotive scheduling than the basic ant colony algorithm.

Virtualization and cloud computing platform brought the new combination of resources integration and use mode. Cloud computing distributes computing tasks to large pools consists of computing resources to make all kinds of application system could acquire services according to need; The Virtualization technology can greatly improve the efficiency and availability of resources and application in cloud computing system, and greatly simplified IT infrastructure, optimize resource and reduce the risk. In order to reduce the spending of virtual machines in the virtualization environment, improve the virtualization implementation efficiency, based on the virtual cloud platform, we propose a computing resources load balance management strategy based on the time axis and introduce the CPU time assignment algorithm.

Scheduling is a very important part of the cloud computing system. This paper introduces an optimized algorithm for task scheduling based on genetic simulated annealing algorithm in cloud computing and its implementation. Algorithm considers the QOS requirements of different type tasks, the QOS parameters are dealt with dimensionless. The algorithm efficiently completes tasks scheduling in the cloud computing environment computing.

With regard to the research on MANET mobile model and routing protocol issues, according to the behaviors of community mobile nodes, a community wireless mobile model based on AOC. Autonomous system was established by making use of AOC-by-prototyping combining with trial-and-Error process. This paper does simulation experiment through NS-2 simulation platform, showing that in this model DSR and AODV routing protocols are relatively stable in the aspect of routing overhead; however in the window size DSR routing protocol is the best.

A novel amperometric immunoassay for identification of Escherichia coli (E.coli) in a matrix containing zirconium dioxide nanoparticles (ZrO 2 ) was described. Firstly, the antibody of E.coli (anti E.coli) was immobilized on a glassy carbon electrode (GCE) modified with carbon nanotubes (CNTs) using ZrO 2 nanoparticles, colloidal gold (Au) and poly-Lysine (pLL) composite membrane (ZrO 2 -Au-pLL-anti-E.coli) aiming to maintain the antibody's bioactivity. Then one novel sebacato-bridged Co(□) complex Co(suc)(bpy)(H 2 O) 2 (referred to as CoL, suc=succinic acid; bpy=2,2′-bipyridine) was adsorbed onto the surface of ZrO 2 -Au-pLL-anti-E.coli composite membrane, thus the immunosensor (GCE|CNTs|ZrO 2 -Au-pLL-anti-E.coli|CoL) for determination of E.coli was constructed based on one step immunoreaction using cyclic voltammetry (CV) method. CoL can be employed as an electron transfer mediator for catalytic activity detection of H 2 O 2 . After the immunosensor was incubated with E.coli solution at room temperature for 20 min, the electron transfer access of CoL to H 2 O 2 was partly inhibited, which leads to a linear decrease of the catalytic efficiency to H 2 O 2 . The immunosensor was employed to determine E.coli in samples and the results were consistent to the tradition enzyme-linked immunosorbent assays (ELISA) method. The proposed ampero metric immunosensor was sensitive, quick and disposable, which was suitable for determination of E.coli in polluted waters for public health and environmental protection.

A novel immunoassay method based on hydride generation-atomic fluoresce spectrometer (HG-AFS) with arsenic (As) absorbed Fe 3 O 4 @Au (Fe 3 O 4 @Au-As) nanoparticles as tags to the antibody for the rapid and early diagnosis of α-fetoprotein (AFP) in primary carcinoma of the liver is proposed. The new approach combined the use of Fe 3 O 4 @Au-As nanoparticles labeled antibody, and HG-AFS detection for sandwich-type immunoassay. Firstly, Fe 3 O 4 @Au-As nanoparticles were prepared. Then Fe 3 O 4 @Au-As composite is used to immoblize HRP-labeled anti-AFP as secondary antibody (bionanospheres). The bionanospheres were characterized by transmission electron microscopy (TEM), and ultraviolet visible spectroscopy (UV-Vis). Sandwich-type protocol was successfully introduced to develop a new high-efficiency HG-AFS immunoassay. An important advantage of HG-AFS is high sensitivity to the detection of As. And in the immune-complex the concentration of As is high and has a linear relationship with AFP antigen, which could enlarge the signals. The antigen concentration, thus, was determined by measuring the arsenic in the immune complex with HG-AFS, which is quite promising for the detection of low concentration AFP at early stage of primary carcinoma of the liver.

On-chip spiral inductors with high quality factors are very important in many RF circuits. In this paper, spiral inductors are analyzed to study the influence of substrate and spiral structure on an inductor's performance in the multi-GHz frequency range. Firstly, the inductors with different substrate conductivity, thickness and permittivity of the dielectric layer are compared, and a general guide is given that the substrate of a good performance inductor should be light impurity, the dielectric layer should be thick, and use a low k material. And then, this paper presents a novel spiral structure with gradually reduced metal width and space from outside to inside, which can help to alleviate the problems of the magnetic field intensity of a spiral inductor increasing gradually from outside to inside. Compared to conventional inductor, the maximum Q of inductor using gradually changed structure increases by 13.66%, thus the results have corroborated the validity of the proposed method.

A dual-band power amplifier (PA) which operates at two specific frequencies of 1.8GHz and 2.0GHz simultaneously is designed. The input matching circuit has one access with a special matching network which resonates at two frequencies. The output matching circuit is the simple L-type matching network and was designed under the guide of load-pull methodology. The simulated results show that, at the two frequencies, the S21 achieves 12.63dB and 13.64dB respectively, the S11 reaches -11.88dB and -10.76dB. The 1-dB power compressions of the two frequencies both achieve 6 dBm and the power gain achieves 10dB.

We report a novel PIN diode SiGe HBT variable gain amplifier (VGA) suited for the standard of WCDMA. The PIN diode which is employed in the feedback loop of the VGA play as a variable resistor to realize the gain control function. By adjusting the bias of the diode, the gain of the VGA can be changed. An inductor is utilized in the feedback loop to reduce the noise figure of the circuit. After matching the circuit, we get a variable gain amplifier with 21dB dynamic range, about 19dB maximum gain, and 2.6dB minimum noise figure. This work demonstrates a new method controlling the gain by adding a PIN diode in the feedback loop except changing the bias of the transistor.

This paper presents a SiGe HBT low noise amplifier (LNA) using resistive feedback scheme for ultra-wideband (UWB) applications. This amplifier is implemented in 0.35um SiGe process and is unconditionally stable. The simulated results show the LNA has over 21dB gain with less than 1dB variation over 3-10GHz. The matched input and output reflection are all less than -10dB. The noise figure is 4.03dB at 3GHz and increases to 4.85dB at 10GHz, which is good enough for the resistive feedback LNA.

A UWB LNA (low noise amplifier) based on 0.35 ?m SiGe BiCMOS technology is presented in this paper. This LNA adopts a resistance feedback topology to optimize the gain and noise figure. The serial inductance at the base is used to matching input impedance and decreasing group delay variation. The simulation results indicate that the gain of LNA reaches 12.5 dB with the variation of 1.9 dB and the power consuming is 6.3 mW in full band from 3.1 GHz to 10.6 GHz. This SiGe UWB LNA exhibits less than 5 ps group delay variation and less than 3.85 dB NF over the entire band.

A dual wavelength-selectable InGaAsP/InP distributed feedback (DFB) laser with a complex-coupled Bragg grating is presented. An n-doped reverse layer is buried periodically in the index-coupled Bragg grating, which causes a spatial modulation of the carrier concentration in the active region, and so induces the weak gain-coupled to the index-coupled grating. Two wavelengths of 1.51 um and 1.53 um are realized under different work conditions. The side mode suppression ratios (SMSRs) of both wavelengths reach 40 dB benefiting from the single-mode character of the complex-couple grating. This device can be used in coarse wavelength division multiplexer (CWDM) communication system as the light source because of its low-cost and convenience.

A high dynamic range linear-in-dB variable gain amplifier (VGA) using SiGe HBT devices for WCDMA applications is presented in this paper. The gain is achieved through four stages of amplifiers. The first, third and the fourth stage is the normal amplify stage, and the second stage is the gain control stage. The gain control is implemented by adjusting the bias of the second amplifier. The VGA is driven by a 2.7-V power supply, and has a 49 dB linear gain control range varying from 11 dB to 60 dB when control voltage varies from 0 to 2.7 V. The maximum gain is 60 dB at the frequency of 1.95 GHz, the noise figure is 4.685 dB at maximum gain, input/output VSWRs keep low and constant. The VGA is fabricated in a 0.35 mum fT = 43 GHz silicon germanium heterojunction technology.