An enzymatic biofuel cell (EBFC) is a device that uses an enzyme as a catalyst to convert chemical energy into electrical energy by a redox reaction to generate electricity. EBFC has the advantage that it can operate under mild conditions (normal temperature, normal pressure, and near neutral pH) and can use various energy sources such as sugar and alcohol. Hoshi et al. reported EBFC of glucose fuel using graphene-coated carbon fiber cloth (GCFC) with a large specific surface area. However, it was considered that GOD was affected by dissolved oxygen in the fuel and generated hydrogen peroxide, which hindered the reaction. In order to further increase the output, it was necessary to improve the performance of the anode with a novel enzyme that is less affected by oxygen and generates electricity from glucose. Therefore, we focused on FAD glucose dehydrogenase (FAD-GDH). It can generate electricity with glucose fuel by using it as a catalyst like GOD. Characteristic is that it is resistant to impurities such as maltose and galactose and is not easily affected by oxygen. It was thought that this would alleviate the concern about hydrogen peroxide and improve the output.

In this paper, the distributed cooperative communication of unmanned aerial vehicles (UAVs) is studied, where the condition number (CN) and the inner product (InP) are used to measure the quality of communication links. By optimizing the relative position of UAVs, large channel capacity and stable communication links can be obtained. Using the spherical wave model under the line of sight (LOS) channel, CN expression of the channel matrix is derived when there are Nt transmitters and two receivers in the system. In order to maximize channel capacity, we derive the UAVs position constraint equation (UAVs-PCE), and the constraint between BS elements distance and carrier wavelength is analyzed. The result shows there is an area where no matter how the UAVs' positions are adjusted, the CN is still very large. Then a special scenario is considered where UAVs form a rectangular lattice array, and the optimal constraint between communication distance and UAVs distance is derived. After that, we derive the InP of channel matrix and the gradient expression of InP with respect to UAVs' position. The particle swarm optimization (PSO) algorithm is used to minimize the CN and the gradient descent (GD) algorithm is used to minimize the InP by optimizing UAVs' position iteratively. Both of the two algorithms present great potentials for optimizing the CN and InP respectively. Furthermore, a hybrid algorithm named PSO-GD combining the advantage of the two algorithms is proposed to maximize the communication capacity with lower complexity. Simulations show that PSO-GD is more efficient than PSO and GD. PSO helps GD to break away from local extremum and provides better positions for GD, and GD can converge to an optimal solution quickly by using the gradient information based on the better positions. Simulations also reveal that a better channel can be obtained when those parameters satisfy the UAVs position constraint equation (UAVs-PCE), meanwhile, theory analysis also explains the abnormal phenomena in simulations.

The linguistic Multi-Criteria Group Decision-Making (MCGDM) problem involves various types of uncertainties. To deal with this problem, a new linguistic MCGDM method combining cloud model and evidence theory is thus proposed. Cloud model is firstly used to handle the fuzziness and randomness of the linguistic concept, by taking both the average level and fluctuation degree of the linguistic concept into consideration. Hence, a method is presented to transform linguistic variables into clouds, and then an asymmetrical weighted synthetic cloud is proposed to aggregate the clouds of decision makers on each criterion. Moreover, evidence theory is used to handle the imprecision and incompleteness of the group assessment, with the belief degree and the ignorance degree. Hence, the conversion from the cloud to the belief degree is investigated, and then the evidential reasoning algorithm is adopted to aggregate the criteria values. Finally, the average utility is applied to rank the alternatives. A numerical example, which is given to confirm the validity and feasibility, also shows that the proposed method can take advantage of cloud model and evidence theory to efficiently deal with the uncertainties caused by both the linguistic concept and group assessment.

The demand for enzymatic biofuel cells (EBFCs) as power sources or auxiliary power sources for small devices is expected to increase in the near future. EBFCs have advanced properties and do not require a separator, depending on the substrate specificity of the enzyme. Two direct electron transfer (DET)-type enzymes were used to modify anodes (length 5mm, width 4mm) by a chemical modification method using a condensation agent. The DET-type enzymes used in this study were pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) with glucose as a reaction substrate and fructose dehydrogenase (FDH) using fructose as a reaction substrate. Carboxyl groups were attached to multi-walled carbon nanotubes (MWCNTs) that act as catalyst carriers, activated to other functional groups, and reacted with the amino groups of the enzyme by the condensation agent to form covalent bonds. As a result, the upper limit of the concentration, considered to be the reaction limit, was raised as compared with that of EBFC modified with only one kind of enzyme for each electrode prepared by the same process. The output voltage was 0.155V, and the maximum power density was 80.08µW/cm2.

This paper demonstrates a PLL compiler that generates the final GDSII data from a specification of input and output frequencies with PVT corner conditions. A Pulse Width Controlled PLLs (PWPLL) is composed of digital blocks, and thus suitable for being designed using a standard cell library and being layed out with a commercially available place-and-route (P&R) tool. A PWPLL has 8 design parameters. Our PLL compiler decides the 8 parameters and confirms the PLL operation with the following functions: 1) calculates rough parameter values based on an analytical model, 2) generates SPICE and gate-level verilog netlists with given parameter values, 3) runs SPICE simulations and analyzes the waveform, to examine the oscillation frequency or the voltage of specified nodes at a given time, 4) changes the parameter values to an appropriate direction depending on the waveform analyses to obtain the optimized parameter values, 5) generates scripts that can be used in commercial design tools and invokes the tools with the gate-level verilog netlist to get the final LVS/DRC-verified GDSII data from a P&R and a verification tools, and finally 6) generates the necessary characteristic summary sheets from the post-layout SPICE simulations extracted from the GDSII. Our compiler was applied to an 0.18µm standard CMOS technology to design a PLL with 600MHz output, 600/16MHz input frequency, and confirms the PLL operation with 1.2mW power and 85µm×85µm layout area.

This paper presents an improved Mobile WiMAX handover (HO) algorithm for real-time application by using a Link_Going_Down (LGD) trigger technique. Mobile WiMAX is a wireless networking system based on the IEEE 802.16e standard. In order to support phone mobility, a HO scheme of some kind must be adopted, and in this standard hard handover (HHO) is defined as mandatory. Since, the fact that there will be a pause in data transmission during the HO process, delay in communication will occur. Thus, the HO time (>50ms) can degrade system performance when implemented in real-time applications such as Video Streaming or Internet Protocol Television (IPTV). Additionally, the HHO takes approximately 300ms because the HO process doesn't start at the best point. The HHO standard considers only the received signal strength (RSS) to decide initiation. The mobile station velocity is also an important factor in HO initiation that should not be neglected. To deal with the problems of handover delay, this paper proposes a new HO scheme. This scheme adopts the dynamic HO threshold that used LGD technique to define the starting HO process. This technique is based on the RSSD (measured by the Doppler Effect technique), mobile velocities and handover time. Consequently, the HO process starts at the right time and HO time is reduced (<50 ms) and the network resource utilization is enhanced to be more efficient.

Heterogeneous network (HetNet) is now considered to be a promising technique for enhancing the coverage and reducing the transmit power consumption of the next 5G system. Deploying small cells such as femtocells in the current macrocell networks achieves great spatial reuse at the cost of severe cross-tier interference from concurrent transmission. In this situation, two novel energy efficient power control and resource allocation schemes in terms of energy efficiency (EE)-fairness and EE-maximum, respectively, are investigated in this paper. In the EE-fairness scheme, we aim to maximize the minimum EE of the femtocell base stations (FBSs). Generalized Dinkelbach's algorithm (GDA) is utilized to tackle this optimization problem and a distributed algorithm is proposed to solve the subproblem in GDA with limited intercell coordination, in which only a few scalars are shared among FBSs. In the EE-maximum scheme, we aim to maximize the global EE of all femtocells which is defined as the aggregate capacity over the aggregate power consumption in the femtocell networks. Leveraged by means of the lower-bound of logarithmic function, a centralized algorithm with limited computational complexity is proposed to solve the global EE maximization problem. Simulation results show that the proposed algorithms outperform previous schemes in terms of the minimum EE, fairness and global EE.

By investigating the properties that the offsets should satisfy, this letter presents a brief proof of general QAM Golay complementary sequences (GCSs) in Cases I-III constructions. Our aim is to provide a brief, clear, and intelligible derivation so that it is easy for the reader to understand the known Cases I-III constructions of general QAM GCSs.

Based on the non-standard generalized Boolean functions (GBFs) over Z4, we propose a new method to convert those functions into the 16-QAM Golay complementary sequences (CSs). The resultant 16-QAM Golay CSs have the upper bound of peak-to-mean envelope power ratio (PMEPR) as low as 2. In addition, we obtain multiple 16-QAM Golay CSs for a given quadrature phase shift keying (QPSK) Golay CS.

The impact of non-ideal delay line (DL) along with group delay ripple (GDR) on the performance of ultra wide bandwidth (UWB) system has not yet been studied in previous literatures. In this paper, according to the currently designed DLs, we propose a statistical GDR model to achieve a practical UWB DL, and investigate the degradation in average bit error rate (BER) caused by the GDR for the transmitted-reference (TR) UWB communication systems. According to the analysis results, an improved autocorrelation receiver (AcR) is proposed. Through Monte Carlo simulations, the great performance improvement of the proposed AcR is verified by comparing it with the conventional TR AcR under non-ideal DL conditions. The proposed receiver framework is simple enough to enable a tractable analysis, and provides valuable insights for designing a practical TR UWB AcR that experiences GDR.

Different from distributed baluns, active baluns have group delay variations in the lower bands related to inherent internal capacitances and resistance in transistors. A negative group delay (NGD) circuit is employed as a compensator of group delay variation for an ultra-wideband (UWB) active balun. First, three-cell NGD circuit is inserted into a simple active balun circuit for realizing both group delay compensation and return loss improvement. The simulated results show a group delay variation of 4.8 ps and an input return loss of above 11.5 dB in the UWB band (3.1-10.6 GHz). Then, a pair of one-cell NGD circuits is added to reduce the remaining group delay variation (3.4 ps in simulation). The circuit with the NGD circuits was fabricated on an InGaP/GaAs HBT MMIC substrate. The measured results achieved a group delay variation of 7.7 ps, a gain variation of 0.5 dB, an input return loss of greater than 10 dB, and an output return loss of larger than 8.1 dB in the UWB band.

We propose a polarization mode dispersion (PMD) design for high-speed wavelength-division multiplexing (WDM) backbone network systems based on field PMD measurements on installed optical fibers for long-term commercial use. Implementing a high-speed network system on an installed fiber requires measuring PMD, because the PMD characteristics of most installed fibers are unknown. For enhanced practicality, we must be able to precisely evaluate PMD characteristics precisely with just one measurement. To understand the statistical properties of measured PMD values, we use the Jones Matrix Eigenanalysis (JME) method to conduct long-term (12 months) PMD measurements on installed fibers. We statistically analyze the measurement results and confirm that the measured values match the theory that considers the accuracy of the measurement instrument. This enables a PMD design of desired outage probability based on PMD measurements of installed fibers. We also carry out a 43-Gb/s return-to-zero differential quadrature phase shift keying (RZ-DQPSK) signal transmission with high PMD fibers in order to confirm the effectiveness of our PMD design. The PMD values of the in-line amplifier transmission line are settled so as to meet the worst value of the design. We confirm that 43-Gb/s RZ-DQPSK signals are stably transmitted at the design value.

Recently several weighted clustering algorithms have been proposed, however, to the best of our knowledge; there is none that propagates weights to other nodes without weight message for leader election, normalizes node parameters and considers neighboring node parameters to calculate node weights. In this paper, we propose an Energy Efficient and Stable Weight Based Clustering (EE-SWBC) algorithm that elects cluster heads without sending any additional weight message. It propagates node parameters to its neighbors through neighbor discovery message (HELLO Message) and stores these parameters in neighborhood list. Each node normalizes parameters and efficiently calculates its own weight and the weights of neighboring nodes from that neighborhood table using Grey Decision Method (GDM). GDM finds the ideal solution (best node parameters in neighborhood list) and calculates node weights in comparison to the ideal solution. The node(s) with maximum weight (parameters closer to the ideal solution) are elected as cluster heads. In result, EE-SWBC fairly selects potential nodes with parameters closer to ideal solution with less overhead. Different performance metrics of EE-SWBC and Distributed Weighted Clustering Algorithm (DWCA) are compared through simulations. The simulation results show that EE-SWBC maintains fewer average numbers of stable clusters with minimum overhead, less energy consumption and fewer changes in cluster structure within network compared to DWCA.

This paper describes the characteristic of negative group delay (NGD) circuits for various configurations including first-order, distributed, and second-order RC circuit configurations. This study includes locus, magnitude, and phase characteristics of the NGD circuits. The simplest NGD circuit is available using first-order RC or RL configuration. As an example of distributed circuit configuration, it is verified that losses in a distributed line causes NGD characteristic at higher cut-off band of a coupled four-line bandpass filter. Also, novel wideband NGD circuits using second-order RC configuration, instead of conventional RLC configuration, are proposed. Adding a parallel resistor to a parallel-T filter enables NGD characteristic to it. Also, a Wien-Robinson bridge is modified to have NGD characteristic by controlling the voltage division ratio. They are fabricated on MMIC substrate, and their NGD characteristics are verified with measured results. They have larger insertion loss than multi-stage RLC NGD circuits, however they can realize second-order NGD characteristic without practical implementation of inductors.

In previous research, we have proposed a parallel block scaled gradient with decentralized step-size (PBSGDS) method. The method circumvents the difficulty of determining a step-size in the distributed computing environment and enables the proposed parallel algorithm to execute in a distributed computer network with limited amount of date transfer. In this paper, we implement the parallel algorithm within two real Independent System Operator (ISO) Networks, including homogeneous and heterogeneous types PCs-Networks environments, and demonstrate the computational efficiency and numerical satiability through numerous simulation test results in solving a Convex Block Additive Unconstrained (CBAU) optimization problem. Furthermore, the test results show that the performance of the proposed parallel algorithm appears more attractive due to the asynchronous effect in the distributed computing environment.

An audio-based shot classification method for audiovisual indexing is proposed in this paper. The proposed method mainly consists of two parts, an audio analysis part and a shot classification part. In the audio analysis part, the proposed method utilizes both principal component analysis (PCA) and Mahalanobis generalized distance (MGD). The effective features for the analysis can be automatically obtained by using PCA, and these features are analyzed based on MGD, which can take into account the correlations of the data set. Thus, accurate analysis results can be obtained by the combined use of PCA and MGD. In the shot classification part, the proposed method utilizes a fuzzy algorithm. By using the fuzzy algorithm, the mixing rate of the multiple audio sources can be roughly measured, and thereby accurate shot classification can be attained. Results of experiments performed by applying the proposed method to actual audiovisual materials are shown to verify the effectiveness of the proposed method.

A new cell structure Power MOSFET, which exhibits a lower on-state resistance and lower gate charge than the conventional layout geometry, is proposed in this research. Vertical Power MOSFETs are generally designed by either squared (closed) cell or stripe (linear) cell geometry; each has its own advantages and drawbacks. Typically, closed cell design has lower on resistance but higher gate charge characteristics than the linear one. In this study, we propose, fabricate, and analyze a "wing cell" structure Power MOSFET, which can have lower on resistance and lower gate charge performances than the closed cell structure. In addition, the wing cell design can avoid the "closed concept" patents.

This paper deals with the statistical modeling of a Time-Frequency Series of Speech (TFSS), obtained by Short-Time Fourier Transform (STFT) analysis of the speech signal picked up by a linear microphone array with two elements. We have attempted to find closer match between the distribution of the TFSS and theoretical distributions like Laplacian Distribution (LD), Gaussian Distribution (GD) and Generalized Gaussian Distribution (GGD) with parameters estimated from the TFSS data. It has been found that GGD provides the best models for real part, imaginary part and polar magnitudes of the time-series of the spectral components. The distribution of the polar magnitude is closer to LD than that of the real and imaginary parts. The distributions of the real and imaginary parts of TFSS correspond to strongly LD. The phase of the TFSS has been found uniformly distributed. The use of GGD based model as PDF in the fixed-point Frequency Domain Independent Component Analysis (FDICA) provides better separation performance and improves convergence speed significantly.

We developed a new method to improve the efficiency of the PDP (plasma display panel) by the use of a novel protecting film or Gd doped MgO film. In the cells of the PDP, the VUV (vacuum ultraviolet ray) is generated by Xe discharge. The VUV is simply absorbed by the protecting film or MgO film. Therefore, normally the absorbed VUV doesn't contribute to the light conversion efficiency. However, the novel protecting film or MgO:Gd film radiates the ultraviolet ray of which 317 nm wavelength, by the irradiation of the shorter wavelength VUV, and it excites the blue phosphor. Consequently the efficiency of blue emission is improved.

This paper proposes a statistical design approach for Non-Return-to-Zero (NRZ) 40 Gbit/s systems with Forward Error Correction (FEC); the approach considers Polarization Mode Dispersion (PMD). We introduce a fluctuating PMD emulator to experimentally clarify FEC performance in PMD-limited systems. By using the proposed design approach, and considering the FEC relaxation effect on PMD, the maximum transmission distance of an NRZ 40 Gbit/s system without PMD compensation is estimated as several hundreds of km depending on the number of cable concatenations per link and the probability threshold of system acceptance.