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[Keyword] anisotropic(38hit)

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  • Development of Liquid-Phase Bioassay Using AC Susceptibility Measurement of Magnetic Nanoparticles Open Access

    Takako MIZOGUCHI  Akihiko KANDORI  Keiji ENPUKU  

     
    PAPER

      Pubricized:
    2023/11/21
      Vol:
    E107-C No:6
      Page(s):
    183-189

    Simple and quick tests at medical clinics have become increasingly important. Magnetic sensing techniques have been developed to detect biomarkers using magnetic nanoparticles in liquid-phase assays. We developed a biomarker assay that involves using an alternating current (AC) susceptibility measurement system that uses functional magnetic particles and magnetic sensing technology. We also developed compact biomarker measuring equipment to enable quick testing. Our assay is a one-step homogeneous assay that involves simply mixing a sample with a reagent, shortening testing time and simplifying processing. Using our compact measuring equipment, which includes anisotropic magneto resistance (AMR) sensors, we conducted high-sensitivity measurements of extremely small amounts of two biomarkers (C-reactive protein, CRP and α-Fetoprotein, AFP) used for diagnosing arteriosclerosis and malignant tumors. The results indicate that an extremely small amount of CRP and AFP could be detected within 15 min, which demonstrated the possibility of a simple and quick high-sensitivity immunoassay that involves using an AC-susceptibility measurement system.

  • Hole Transport Property of α-phenyl-4'-(diphenylamino)stilbene Single Crystal Prepared Based on Solubility and Supersolubility Curves

    Mitsuhiko KATAGIRI  Shofu MATSUDA  Norio NAGAYAMA  Minoru UMEDA  

     
    PAPER

      Vol:
    E102-C No:2
      Page(s):
    132-137

    We describe the preparation of an α-phenyl-4'-(diphenylamino)stilbene (TPA) single crystal and the evaluation of its hole transport property. Based on the characterization using optical microscopy, polarizing microscopy, and X-ray diffraction, a large-scale TPA single crystal of dimensions 7.0×0.9×0.8mm is successfully synthesized using a solution method based on the solubility and supersolubility curves of the TPA. Notably, the current in the long-axis direction is larger than those in the short-axis and thickness directions (i(long) > i(short) > i(thickness)), which reveals the anisotropic charge transfer of the TPA single crystal. The observed anisotropic conductivity is well explained by the orientation of the triphenylamine unit in the TPA single crystal. Furthermore, the activation energy of the long-axis direction in the TPA single crystal is lower than that of the short-axis in TPA and all the axes in the α-phenyl-4'-[bis(4-methylphenyl)amino]stilbene single crystal reported in our previous study.

  • Transmission Property Analysis of Optically-Anisotropic Dielectric Multilayer for Thin Wide-Viewing-Angle Reflective Polarizer Open Access

    Kunihiko AKAHANE  Takahiro ISHINABE  Yosei SHIBATA  Hideo FUJIKAKE  

     
    INVITED PAPER

      Vol:
    E100-C No:11
      Page(s):
    998-1004

    We show that light leakage that occurs in reflective polarizers at large angles of incidence can be suppressed by using anisotropic dielectric multilayers with larger reflective indices in thickness direction and that the interference-included 2×2 Jones matrix method is useful for the investigation of the optical propagation properties of the dielectric multilayers. The thickness of the reflective polarizer can also be reduced by optimizing the distribution of the multilayers in the stack, whilst considering the visual sensitivity. These results indicate that it is possible to realize a high-quality liquid crystal display with wide viewing angles and high light utilization efficiency.

  • Transient Analysis of Anisotropic Dielectrics and Ferromagnetic Materials Based on Unconditionally Stable Perfectly-Matched-Layer (PML) Complex-Envelope (CE) Finite-Difference Time-Domain (FDTD) Method

    Sang-Gyu HA  Jeahoon CHO  Kyung-Young JUNG  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2017/03/14
      Vol:
    E100-B No:10
      Page(s):
    1879-1883

    Anisotropic dielectrics and ferromagnetic materials are widely used in dispersion-engineered metamaterials. For example, nonreciprocal magnetic photonic crystals (MPhCs) are periodic structures whose unit cell is composed of two misaligned anisotropic dielectric layers and one ferromagnetic layer and they have extraordinary characteristics such as wave slowdown and field amplitude increase. We develop an unconditionally stable complex-envelop alternating-direction-implicit finite-difference time-domain method (CE-ADI-FDTD) suitable for the transient analysis of anisotropic dielectrics and ferromagnetic materials. In the proposed algorithm, the perfectly-matched-layer (PML) is straightforwardly incorporated in Maxwell's curl equations. Numerical examples show that the proposed PML-CE-ADI-FDTD method can reduce the CPU time significantly for the transient analysis of anisotropic dielectrics and ferromagnetic materials while maintaining computational accuracy.

  • Vehicle Classification under Different Feature Sets with a Single Anisotropic Magnetoresistive Sensor

    Chang XU  Yingguan WANG  Yunlong ZHAN  

     
    PAPER

      Vol:
    E100-A No:2
      Page(s):
    440-447

    This paper focus on the development of a single portable roadside magnetic sensor for vehicle classification. The magnetic sensor is a kind of anisotropic magnetic device that do not require to be embedded in the roadway-the device is placed next to the roadway and measure traffic in the immediately adjacent lane. A novel feature extraction and comparison approach is presented for vehicle classification with a single magnetic sensor, which is based on four different feature sets extracted from the detected magnetic signal. Furthermore, vehicle classification has been achieved with three common classification algorithms, including support vector machine, k-nearest neighbors and back-propagation neural network. Experimental results have demonstrated that the Peak-Peak feature set with back-propagation neural network approach performs much better than other approaches. Besides, the normalization technology has been proved it does work.

  • A Study on Single Polarization Guidance in Photonic Band Gap Fiber with Anisotropic Lattice of Circular Air Holes

    Kazuki ICHIKAWA  Zejun ZHANG  Yasuhide TSUJI  Masashi EGUCHI  

     
    PAPER

      Vol:
    E99-C No:7
      Page(s):
    774-779

    We propose a novel single polarization photonic band gap fiber (SP-PBGF) with an anisotropic air hole lattice in the core. An SP-PBGF with an elliptical air hole lattice in the core recently proposed can easily realize SP guidance utilizing the large difference of cutoff frequency for the x- and y-polarized modes. In this paper, in order to achieve SP guidance based on the same principle of this PBGF, we utilize an anisotropic lattice of circular air holes instead of elliptical air holes to ease the fabrication difficulty. After investigating the influence of the structural parameters on SP guidance, it is numerically demonstrated that the designed SP-PBGF has 381 nm SP operating band.

  • Usefulness of Transmission Ellipsometric Method for Evaluation of Electro-optic Materials

    Toshiki YAMADA  Akira OTOMO  

     
    BRIEF PAPER

      Vol:
    E98-C No:2
      Page(s):
    143-146

    A transmission ellipsometric method without an aperture was recently developed to characterize the electro-optic (EO) performance of EO polymers. The method permits much simpler optical setup compared to the reflection method, and allows easy performance of the incident angle dependence measurements using a conventional glass substrate and uncollimated beam. This paper shows the usefulness of this method for a simple and reliable evaluation of the EO coefficient both for organic and inorganic EO materials, as well as analysis for uniaxial anisotropic materials.

  • Ray-Model-Based Routing for Underwater Acoustic Sensor Networks Accounting for Anisotropic Sound Propagation

    Ping WANG  Lin ZHANG  Victor O.K. LI  

     
    PAPER-Network

      Vol:
    E96-B No:8
      Page(s):
    2060-2068

    In classical routing protocols, geographical distances/locations are typically used as the metric to select the best route, under the assumption that shorter distances exhibit lower energy consumption and nodes within the communication range of the sender can receive packets with a certain success probability. However, in underwater acoustic sensor networks (UASNs), sound propagation in the ocean medium is more complex than that in the air due to many factors, including sound speed variations and the interaction of sound waves with the sea surface and floor, causing the sound rays to bend. Therefore, propagation of sound is anisotropic in water, and may cause a phenomenon called shadow zone where nodes in the communication range of the sender cannot hear any signal. This renders conventional routing protocols no longer energy-efficient. In this paper, we make use of the ray-model to account for the environment-dependent behavior of the underwater channel, re-define nodes' one-hop neighbors based on signal attenuation rather than geographical distance, and design a distributed energy-efficient routing protocol for UASNs. Results show that our ray-model-based routing policy consistently outperforms the shortest path policy, and performs very close to the optimal one in several scenarios.

  • Anisotropic Lp Poisson Disk Sampling for NPR Image with Adaptively Shaped Pieces

    Tao WANG  Zhongying HU  Kiichi URAHAMA  

     
    LETTER-Computer Graphics

      Vol:
    E96-D No:6
      Page(s):
    1406-1409

    A non-photorealistic rendering technique is presented for generating images such as stippling images and paper mosaic images with various shapes of paper pieces. Paper pieces are spatially arranged by using an anisotropic Lp poisson disk sampling. The shape of paper pieces is adaptively varied by changing the value of p. We demonstrate with experiments that edges and details in an input image are preserved by the pieces according to the anisotropy of their shape.

  • A Modified Pulse Coupled Neural Network with Anisotropic Synaptic Weight Matrix for Image Edge Detection

    Zhan SHI  Jinglu HU  

     
    PAPER-Image

      Vol:
    E96-A No:6
      Page(s):
    1460-1467

    Pulse coupled neural network (PCNN) is a new type of artificial neural network specific for image processing applications. It is a single layer, two dimensional network with neurons which have 1:1 correspondence to the pixels of an input image. It is convenient to process the intensities and spatial locations of image pixels simultaneously by applying a PCNN. Therefore, we propose a modified PCNN with anisotropic synaptic weight matrix for image edge detection from the aspect of intensity similarities of pixels to their neighborhoods. By applying the anisotropic synaptic weight matrix, the interconnections are only established between the central neuron and the neighboring neurons corresponding to pixels with similar intensity values in a 3 by 3 neighborhood. Neurons corresponding to edge pixels and non-edge pixels will receive different input signal from the neighboring neurons. By setting appropriate threshold conditions, image step edges can be detected effectively. Comparing with conventional PCNN based edge detection methods, the proposed modified PCNN is much easier to control, and the optimal result can be achieved instantly after all neurons pulsed. Furthermore, the proposed method is shown to be able to distinguish the isolated pixels from step edge pixels better than derivative edge detectors.

  • Several Types of Antennas Composed of Microwave Metamaterials Open Access

    Tie Jun CUI  Xiao-Yang ZHOU  Xin Mi YANG  Wei Xiang JIANG  Qiang CHENG  Hui Feng MA  

     
    INVITED PAPER

      Vol:
    E94-B No:5
      Page(s):
    1142-1152

    We present a review of several types of microwave antennas made of metamaterials, including the resonant electrically small antennas, metamaterial-substrate patch antennas, metamaterial flat-lens antennas, and Luneburg lens antennas. In particular, we propose a new type of conformal antennas using anisotropic zero-index metamaterials, which have high gains and low sidelobes. Numerical simulations and experimental results show that metamaterials have unique properties to design new antennas with high performance.

  • An Evaluation Method for Anisotropic Absorber Panels Using a Diagonalization Method

    Shinichiro YAMAMOTO  Tohru IWAI  Kenichi HATAKEYAMA  

     
    LETTER

      Vol:
    E93-B No:7
      Page(s):
    1851-1854

    In this paper, an evaluation method for electromagnetic wave absorber with anisotropic reflection properties is discussed. Anisotropic absorber panels have an axis of anisotropy (principal axis). In order to specify the principal axis, the evaluation method based on the diagonalization of reflection coefficient matrix is used. Also, the permittivity of absorber materials is considered.

  • Reflection and Transmission of a TE Plane Wave from a Two-Dimensional Random Slab --- Anisotropic Fluctuation ---

    Yasuhiko TAMURA  Kiyoshi TSUTSUMI  

     
    BRIEF PAPER-Electromagnetic Theory

      Vol:
    E92-C No:12
      Page(s):
    1531-1534

    This paper studies reflection and transmission of a TE plane wave from a two-dimensional random slab with statistically anisotropic fluctuation by means of the stochastic functional approach. By starting with a representation of the random wavefield presented in the previous paper [IEICE Trans. Electron., vol.E92-C, no.1, pp.77-84, Jan. 2009], a solution algorithm of the multiple renormalized mass operator is newly shown even for anisotropic fluctuation. The multiple renormalized mass operator, the first-order incoherent scattering cross section and the optical theorem are numerically calculated and illustrated in figures. The relation between statistical properties and anisotropic fluctuation is discussed.

  • ZnO Belt-Like Structures Grown Using ZnS Substrates with Ga Droplets

    Qing YANG  Miyoko TANAKA  Takahito YASUDA  Hirokazu TATSUOKA  

     
    BRIEF PAPER-Nanomaterials and Nanostructures

      Vol:
    E92-C No:12
      Page(s):
    1479-1482

    A variety of ZnO belt-like structures were synthesized by the heat treatment of ZnS substrates with Ga droplets in the air, and their morphological and structural properties were investigated. Three types of ZnO belts with flat surfaces of (20), (100) and (23) were obtained. As comparison, the ZnO crystal growth was examined by the thermal oxidation of ZnS only. These results highlight the promise of the heat treatment with Ga in the synthesis of oxide nanostructures.

  • Anisotropic Periodic Assemblies and Metamaterials for Applications to Antennas and Microwave Devices Open Access

    John L. VOLAKIS  Gokhan MUMCU  Kubilay SERTEL  

     
    INVITED PAPER

      Vol:
    E90-B No:9
      Page(s):
    2203-2207

    Basic microwave properties of magnetic photonic (MPC) and degenerate band edge (DBE) crystals are investigated mathematically and experimentally. Two dimensional and three dimensional models are considered demonstrating the very high sensitivity and field growth associated with these crystals. A major part of the paper deals with the development of realistic anisotropic periodic structures using a combination of layers constructed from thin film frequency selective surfaces, alumina, titanate and calcium vanadium garnet (CVG) materials. Measurements for antenna applications demonstrate and validate the theoretical performance of the MPC and DBE crystals. The latter part of the paper will present an exciting and promising development relating to microwave circuit applications. Specifically, a novel dual-line printed circuit is presented to emulate propagation in anisotropic media. As such, the MPC and DBE phenomena can be realized using very simple printed circuits (coupled lines). Lastly, physically small printed antennas and arrays based on the coupled transmission lines are presented.

  • Artificial Dielectric Rectangular Resonator with Novel Anisotropic Permittivity and Its TE10δ Mode Waveguide Filter Application

    Achmad MUNIR  Noriaki HAMANAGA  Hiroshi KUBO  Ikuo AWAI  

     
    PAPER

      Vol:
    E88-C No:1
      Page(s):
    40-46

    A miniaturized rectangular resonator made of a novel anisotropic artificial dielectric material is investigated which has advantages of small size and big separation of the higher-modes. To obtain a property of anisotropic permittivity, artificial dielectric material is fabricated by lamination of rectangular metal strips etched on a printed circuit board. Artificial dielectric rectangular resonators are designed to excite TE10δ mode selectively, aligning the rectangular metal patterns along the direction of the mode electric field line. The resonant frequencies and coupling coefficient of artificial dielectric rectangular resonators encapsulated in a metal waveguide are analyzed theoretically, and compared with the experimental result. As a microwave application, a high selectivity TE10δ mode bandpass filter (BPF) using two artificial dielectric rectangular resonators is demonstrated. A two-stage BPF with the center frequency of 1.718 GHz, bandwidth of 78 MHz, and insertion loss of 1.3 dB is successfully realized in a rectangular waveguide.

  • Efficient Edge Function Based Anisotropic Texture Filtering

    Hyun-Chul SHIN  Jin-Aeon LEE  Lee-Sup KIM  

     
    LETTER-Computer Graphics

      Vol:
    E87-A No:4
      Page(s):
    964-970

    In texture mapping, anisotropic filtering methods, which require more texels, have been proposed for high-quality images. Memory bandwidth, however, is still limited by a bottleneck in the texture-filtering hardware. In this paper, we propose anisotropic texture filtering based on edge function. In generating the weight that plays a key role in filtering texels loaded from memory, the edge function gives accurate contribution of texels to the pixel intensity. The quality of images is superior to other methods. For images of the same quality, our method requires less than half the texels of other methods. In other words, the improvement in performance is more than twice that of other methods.

  • FEM-Based Electromagnetic Wave Simulator Running on Some Platforms by Use of Java and a Commercial Tool

    Koichi HIRAYAMA  Naoto KUNIEDA  Yoshio HAYASHI  Masanori KOSHIBA  

     
    PAPER

      Vol:
    E86-C No:11
      Page(s):
    2191-2198

    Making up an electromagnetic wave simulator based on the FEM is tried, which may run on some widely used platforms by use of Java and a single commercial tool. Since the codes and configuration files to be created for this simulator are common, one can construct the simulator running on the platforms at the same time. Using this simulator, the transmission properties of two- and three-dimensional waveguide discontinuities in optical and microwave waveguides are analyzed, the inverse problem in material constant measurement is solved, and the computed results are presented including plots of the electric field distribution.

  • Automated Edge Detection by a Fuzzy Morphological Gradient

    Sathit INTAJAG  Kitti PAITHOONWATANAKIJ  

     
    PAPER-Image

      Vol:
    E86-A No:10
      Page(s):
    2678-2689

    Edge detection has been an essential step in image processing, and there has been much work undertaken to date. This paper inspects a fuzzy mathematical morphology in order to reach a higher-level of edge-image processing. The proposed scheme uses a fuzzy morphological gradient to detect object boundaries, when the boundaries are roughly defined as a curve or a surface separating homogeneous regions. The automatic edge detection algorithm consists of two major steps. First, a new version of anisotropic diffusion is proposed for edge detection and image restoration. All improvements of the new version use fuzzy mathematical morphology to preserve the edge accuracy and to restore the images to homogeneity. Second, the fuzzy morphological gradient operation detects the step edges between the homogeneous regions as object boundaries. This operation uses geometrical characteristics contained in the structuring element in order to extract the edge features in the set of edgeness, a set consisting of the quality values of the edge pixels. This set is prepared with fuzzy logic for decision and selection of authentic edge pixels. For experimental results, the proposed method has been tested successfully with both synthetic and real pictures.

  • Josephson and Quasiparticle Tunneling in Anisotropic High-Tc d-Wave Superconductors

    Ienari IGUCHI  Takuya IMAIZUMI  Tomoyuki KAWAI  Yukio TANAKA  Satoshi KASHIWAYA  

     
    INVITED PAPER-Novel Devices and Device Physics

      Vol:
    E85-C No:3
      Page(s):
    789-796

    We report the measurements on the ramp-edge type Josephson and quasiparticle tunnel junctions with the different interface angle geometry using high-Tc YBa2Cu3O7-y (YBCO) electrodes. The YBCO/I/Ag tunnel junctions with different crystal-interface boundary angles are fabricated for the investigation of zero bias conductance peak. The angle dependent zero bias conductance peak typical to a dx2-y2-wave superconductor is observable. For Josephson junctions, YBCO ramp-edge junctions with different ab-plane electrodes relatively rotated by 45are fabricated using a CeO2 seed-layer technique. The temperature dependence of the maximum Josephson current for YBCO/PBCO/YBCO junctions (PBCO: PrBa2Cu3O7-y) exhibits angle-dependent behavior, qualitatively different from the Ambegaokar-Baratoff prediction. Under microwave irradiation of 9 GHz, the Shapiro steps appear at integer and/or half integer multiples of the voltage satisfying Josephson voltage-frequency relation, whose behavior depends on the sample angle geometry. The results are reasonably interpreted by the dx2-y2-wave theory by taking the zero energy state into account.

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