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[Author] Chao LI(48hit)

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  • A 30 V High Voltage NMOS Structure Design in Standard 5 V CMOS Processes

    Tzu-Chao LIN  Jiin-Chuan WU  

     
    LETTER-Semiconductor Materials and Devices

      Vol:
    E86-C No:11
      Page(s):
    2341-2345

    This paper describes the robust design of the 30 V high voltage NMOS (HVNMOS) structure implemented in a 0.6 µm 5 V standard CMOS processes without any additional masks or process steps. The structure makes use of the field oxide (FOX) and light doping N-well to increase the drain to gate and drain to bulk breakdown voltages, respectively. By varying the six spacing parameters: the channel length, gate overlap FOX, N-well overlap channel length, poly to the active area of the drain (OD2), metal extend beyond the OD2 and N-well extend beyond the OD2 in HVNMOS structure, the breakdown voltage can be improved. The experimental results show that the breakdown voltage of the normal NMOS is 11 V, and the breakdown voltage of the HVNMOS is increased to over 30 V. With the optimized layout parameters of the HVNMOS, it can be increased to 38 V.

  • Roughness Classification with Aggregated Discrete Fourier Transform

    Chao LIANG  Wenming YANG  Fei ZHOU  Qingmin LIAO  

     
    PAPER-Image Recognition, Computer Vision

      Vol:
    E97-D No:10
      Page(s):
    2769-2779

    In this paper, we propose a texture descriptor based on amplitude distribution and phase distribution of the discrete Fourier transform (DFT) of an image. One dimensional DFT is applied to all the rows and columns of an image. Histograms of the amplitudes and gradients of the phases between adjacent rows/columns are computed as the feature descriptor, which is called aggregated DFT (ADFT). ADFT can be easily combined with completed local binary pattern (CLBP). The combined feature captures both global and local information of the texture. ADFT is designed for isotropic textures and demonstrated to be effective for roughness classification of castings. Experimental results show that the amplitude part of ADFT is also discriminative in describing anisotropic textures and it can be used as a complementary descriptor of local texture descriptors such as CLBP.

  • Attention-Guided Spatial Transformer Networks for Fine-Grained Visual Recognition

    Dichao LIU  Yu WANG  Jien KATO  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2019/09/04
      Vol:
    E102-D No:12
      Page(s):
    2577-2586

    The aim of this paper is to propose effective attentional regions for fine-grained visual recognition. Based on the Spatial Transformers' capability of spatial manipulation within networks, we propose an extension model, the Attention-Guided Spatial Transformer Networks (AG-STNs). This model can guide the Spatial Transformers with hard-coded attentional regions at first. Then such guidance can be turned off, and the network model will adjust the region learning in terms of the location and scale. Such adjustment is conditioned to the classification loss so that it is actually optimized for better recognition results. With this model, we are able to successfully capture detailed attentional information. Also, the AG-STNs are able to capture attentional information in multiple levels, and different levels of attentional information are complementary to each other in our experiments. A fusion of them brings better results.

  • RBM-LBP: Joint Distribution of Multiple Local Binary Patterns for Texture Classification

    Chao LIANG  Wenming YANG  Fei ZHOU  Qingmin LIAO  

     
    LETTER-Pattern Recognition

      Pubricized:
    2016/08/19
      Vol:
    E99-D No:11
      Page(s):
    2828-2831

    In this letter, we propose a novel framework to estimate the joint distribution of multiple Local Binary Patterns (LBPs). Multiple LBPs extracted from the same central pixel are first encoded using handcrafted encoding schemes to achieve rotation invariance, and the outputs are further encoded through a pre-trained Restricted Boltzmann Machine (RBM) to reduce the dimension of features. RBM has been successfully used as binary feature detectors and the binary-valued units of RBM seamlessly adapt to LBP. The proposed feature is called RBM-LBP. Experiments on the CUReT and Outex databases show that RBM-LBP is superior to conventional handcrafted encodings and more powerful in estimating the joint distribution of multiple LBPs.

  • Reflection and Rotation Invariant Uniform Patterns for Texture Classification

    Chao LIANG  Wenming YANG  Fei ZHOU  Qingmin LIAO  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2016/02/05
      Vol:
    E99-D No:5
      Page(s):
    1400-1403

    In this letter, we propose a novel texture descriptor that takes advantage of an anisotropic neighborhood. A brand new encoding scheme called Reflection and Rotation Invariant Uniform Patterns (rriu2) is proposed to explore local structures of textures. The proposed descriptor is called Oriented Local Binary Patterns (OLBP). OLBP may be incorporated into other varieties of Local Binary Patterns (LBP) to obtain more powerful texture descriptors. Experimental results on CUReT and Outex databases show that OLBP not only significantly outperforms LBP, but also demonstrates great robustness to rotation and illuminant changes.

  • Recursive Multi-Scale Channel-Spatial Attention for Fine-Grained Image Classification

    Dichao LIU  Yu WANG  Kenji MASE  Jien KATO  

     
    PAPER-Image Recognition, Computer Vision

      Pubricized:
    2021/12/22
      Vol:
    E105-D No:3
      Page(s):
    713-726

    Fine-grained image classification is a difficult problem, and previous studies mainly overcome this problem by locating multiple discriminative regions in different scales and then aggregating complementary information explored from the located regions. However, locating discriminative regions introduces heavy overhead and is not suitable for real-world application. In this paper, we propose the recursive multi-scale channel-spatial attention module (RMCSAM) for addressing this problem. Following the experience of previous research on fine-grained image classification, RMCSAM explores multi-scale attentional information. However, the attentional information is explored by recursively refining the deep feature maps of a convolutional neural network (CNN) to better correspond to multi-scale channel-wise and spatial-wise attention, instead of localizing attention regions. In this way, RMCSAM provides a lightweight module that can be inserted into standard CNNs. Experimental results show that RMCSAM can improve the classification accuracy and attention capturing ability over baselines. Also, RMCSAM performs better than other state-of-the-art attention modules in fine-grained image classification, and is complementary to some state-of-the-art approaches for fine-grained image classification. Code is available at https://github.com/Dichao-Liu/Recursive-Multi-Scale-Channel-Spatial-Attention-Module.

  • A Business Service Model of Smart Home Appliances Participating in the Peak Shaving and Valley Filling Based on Cloud Platform

    Mingrui ZHU  Yangjian JI  Wenjun JU  Xinjian GU  Chao LIU  Zhifang XU  

     
    PAPER

      Pubricized:
    2021/04/22
      Vol:
    E104-D No:8
      Page(s):
    1185-1194

    With the development of power market demand response capability, load aggregators play a more important role in the coordination between power grid and users. They have a wealth of user side business data resources related to user demand, load management and equipment operation. By building a business model of business data resource utilization and innovating the content and mode of intelligent power service, it can guide the friendly interaction between power supply, power grid and load, effectively improve the flexibility of power grid regulation, speed up demand response and refine load management. In view of the current situation of insufficient utilization of business resources, low user participation and imperfect business model, this paper analyzes the process of home appliance enterprises participating in peak shaving and valley filling (PSVF) as load aggregators, and expounds the relationship between the participants in the power market; a business service model of smart home appliance participating in PSVF based on cloud platform is put forward; the market value created by home appliance business resources for each participant under the joint action of market-oriented means, information technology and power consumption technology is discussed, and typical business scenarios are listed; taking Haier business resource analysis as an example, the feasibility of the proposed business model in innovating the content and value realization of intelligent power consumption services is proved.

  • Improving Hessian Matrix Detector for SURF

    Yitao CHI  Zhang XIONG  Qing CHANG  Chao LI  Hao SHENG  

     
    LETTER-Pattern Recognition

      Vol:
    E94-D No:4
      Page(s):
    921-925

    An advanced interest point detector is proposed to improve the Hessian-Matrix based detector of the SURF algorithm. Round-like shapes are utilized as the filter shape to calculate of the Hessian determinant. Dxy can be acquired from approximate round areas, while the regions for computing Dyy or Dxx are designed with the consideration to symmetry and a balance of pixel number. Experimental results indicate that the proposed method has higher repeatability than the one used in SURF, especially in the aspects of rotation and viewpoint, due to the centrosymmetry of the proposed filter shapes. The results of image matching also show that more precision can be gained with the application of proposed detector.

  • Analytical and Numerical Study of the Impact of Halos on Surrounding-Gate MOSFETs

    Zunchao LI  Ruizhi ZHANG  Feng LIANG  Zhiyong YANG  

     
    PAPER-Semiconductor Materials and Devices

      Vol:
    E92-C No:4
      Page(s):
    558-563

    Halo doping profile is used in nanoscale surrounding-gate MOSFETs to suppress short channel effect and improve current driving capability. Analytical surface potential and threshold voltage models are derived based on the analytical solution of Poisson's equation for the fully depleted symmetric and asymmetric halo-doped MOSFETs. The validity of the analytical models is verified using 3D numerical simulation. The performance of the halo-doped MOSFETs are studied and compared with the uniformly doped surrounding-gate MOSFETs. It is shown that the halo-doped channel can suppress threshold voltage roll-off and drain-induced barrier lowering, and improve carrier transport efficiency. The asymmetric halo structure is better in suppressing hot carrier effect than the symmetric halo structure.

  • A Novel Construction of 2-Resilient Rotation Symmetric Boolean Functions

    Jiao DU  Shaojing FU  Longjiang QU  Chao LI  Tianyin WANG  Shanqi PANG  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2021/08/03
      Vol:
    E105-A No:2
      Page(s):
    93-99

    In this paper, by using the properties of the cyclic Hadamard matrices of order 4t, an infinite class of (4t-1)-variable 2-resilient rotation symmetric Boolean functions is constructed, and the nonlinearity of the constructed functions are also studied. To the best of our knowledge, this is the first class of direct constructions of 2-resilient rotation symmetric Boolean functions. The spirit of this method is different from the known methods depending on the solutions of an equation system proposed by Du Jiao, et al. Several situations are examined, as the direct corollaries, three classes of (4t-1)-variable 2-resilient rotation symmetric Boolean functions are proposed based on the corresponding sequences, such as m sequences, Legendre sequences, and twin primes sequences respectively.

  • Throughput Analysis of the IEEE 802.11 DCF under Both Saturated and Non-saturated Conditions

    Chao LIU  Mengtian RONG  

     
    PAPER-Terrestrial Radio Communications

      Vol:
    E92-B No:6
      Page(s):
    2168-2174

    The IEEE 802.11 standard has been extensively deployed all over the world. Many studies have been put on its performance, especially throughput. Most research focused on the analysis of saturated throughput, but non-saturated situation is more usual in practice. By extending a saturation throughput model, a concise and novel model is proposed in this paper, which can be used to analyze both saturated and non-saturated conditions. Moreover, the model can also deal with the heterogeneous condition, which allows stations to have different traffic. Different access mechanisms and packet payloads are used in simulation to validate it, and the results show that the model is accurate.

  • Pattern Synthesis of Sparse Linear Arrays Using Spider Monkey Optimization

    Huaning WU  Yalong YAN  Chao LIU  Jing ZHANG  

     
    PAPER-Antennas and Propagation

      Pubricized:
    2016/10/06
      Vol:
    E100-B No:3
      Page(s):
    426-432

    This paper introduces and uses spider monkey optimization (SMO) for synthesis sparse linear arrays, which are composed of a uniformly spaced core subarray and an extended sparse subarray. The amplitudes of all the elements and the locations of elements in the extended sparse subarray are optimized by the SMO algorithm to reduce the side lobe levels of the whole array, under a set of practical constraints. To show the efficiency of SMO, different examples are presented and solved. Simulation results of the sparse arrays designed by SMO are compared with published results to verify the effectiveness of the SMO method.

  • Document-Level Neural Machine Translation with Associated Memory Network

    Shu JIANG  Rui WANG  Zuchao LI  Masao UTIYAMA  Kehai CHEN  Eiichiro SUMITA  Hai ZHAO  Bao-liang LU  

     
    PAPER-Natural Language Processing

      Pubricized:
    2021/06/24
      Vol:
    E104-D No:10
      Page(s):
    1712-1723

    Standard neural machine translation (NMT) is on the assumption that the document-level context is independent. Most existing document-level NMT approaches are satisfied with a smattering sense of global document-level information, while this work focuses on exploiting detailed document-level context in terms of a memory network. The capacity of the memory network that detecting the most relevant part of the current sentence from memory renders a natural solution to model the rich document-level context. In this work, the proposed document-aware memory network is implemented to enhance the Transformer NMT baseline. Experiments on several tasks show that the proposed method significantly improves the NMT performance over strong Transformer baselines and other related studies.

  • A Motion Detection Model Inspired by the Neuronal Propagation in the Hippocampus

    Haichao LIANG  Takashi MORIE  

     
    PAPER-Vision

      Vol:
    E95-A No:2
      Page(s):
    576-585

    We propose a motion detection model, which is suitable for higher speed operation than the video rate, inspired by the neuronal propagation in the hippocampus in the brain. The model detects motion of edges, which are extracted from monocular image sequences, on specified 2D maps without image matching. We introduce gating units into a CA3-CA1 model, where CA3 and CA1 are the names of hippocampal regions. We use the function of gating units to reduce mismatching for applying our model in complicated situations. We also propose a map-division method to achieve accurate detection. We have evaluated the performance of the proposed model by using artificial and real image sequences. The results show that the proposed model can run up to 1.0 ms/frame if using a resolution of 6460 units division of 320240 pixels image. The detection rate of moving edges is achieved about 99% under a complicated situation. We have also verified that the proposed model can achieve accurate detection of approaching objects at high frame rate (>100 fps), which is better than conventional models, provided we can obtain accurate positions of image features and filter out the origins of false positive results in the post-processing.

  • Generalized Framework to Attack RSA with Special Exposed Bits of the Private Key

    Shixiong WANG  Longjiang QU  Chao LI  Shaojing FU  

     
    PAPER-Cryptography and Information Security

      Vol:
    E100-A No:10
      Page(s):
    2113-2122

    In this paper, we study partial key exposure attacks on RSA where the number of unexposed blocks of the private key is greater than or equal to one. This situation, called generalized framework of partial key exposure attack, was first shown by Sarkar [22] in 2011. Under a certain condition for the values of exposed bits, we present a new attack which needs fewer exposed bits and thus improves the result in [22]. Our work is a generalization of [28], and the approach is based on Coppersmith's method and the technique of unravelled linearization.

  • Impossible Differential Cryptanalysis of Fantomas and Robin

    Xuan SHEN  Guoqiang LIU  Chao LI  Longjiang QU  

     
    LETTER-Cryptography and Information Security

      Vol:
    E101-A No:5
      Page(s):
    863-866

    At FSE 2014, Grosso et al. proposed LS-designs which are a family of bitslice ciphers aiming at efficient masked implementations against side-channel analysis. They also presented two specific LS-designs, namely the non-involutive cipher Fantomas and the involutive cipher Robin. The designers claimed that the longest impossible differentials of these two ciphers only span 3 rounds. In this paper, for the two ciphers, we construct 4-round impossible differentials which are one round more than the longest impossible differentials found by the designers. Furthermore, with the 4-round impossible differentials, we propose impossible differential attacks on Fantomas and Robin reduced to 6 rounds (out of the full 12/16 rounds). Both of the attacks need 2119 chosen plaintexts and 2101.81 6-round encryptions.

  • Research on Mongolian-Chinese Translation Model Based on Transformer with Soft Context Data Augmentation Technique

    Qing-dao-er-ji REN  Yuan LI  Shi BAO  Yong-chao LIU  Xiu-hong CHEN  

     
    PAPER-Neural Networks and Bioengineering

      Pubricized:
    2021/11/19
      Vol:
    E105-A No:5
      Page(s):
    871-876

    As the mainstream approach in the field of machine translation, neural machine translation (NMT) has achieved great improvements on many rich-source languages, but performance of NMT for low-resource languages ae not very good yet. This paper uses data enhancement technology to construct Mongolian-Chinese pseudo parallel corpus, so as to improve the translation ability of Mongolian-Chinese translation model. Experiments show that the above methods can improve the translation ability of the translation model. Finally, a translation model trained with large-scale pseudo parallel corpus and integrated with soft context data enhancement technology is obtained, and its BLEU value is 39.3.

  • Real Time Aerial Video Stitching via Sensor Refinement and Priority Scan

    Chao LIAO  Guijin WANG  Bei HE  Chenbo SHI  Yongling SHEN  Xinggang LIN  

     
    LETTER-Image Processing and Video Processing

      Vol:
    E95-D No:8
      Page(s):
    2146-2149

    The time efficiency of aerial video stitching is still an open problem due to the huge amount of input frames, which usually results in prohibitive complexities in both image registration and blending. In this paper, we propose an efficient framework aiming to stitch aerial videos in real time. Reasonable distortions are allowed as a tradeoff for acceleration. Instead of searching for globally optimized solutions, we directly refine frame positions with sensor data to compensate for the accumulative error in alignment. A priority scan method is proposed to select pixels within overlapping area into the final panorama for blending, which avoids complicated operations like weighting or averaging on pixels. Experiments show that our method can generate satisfying results at very competitive speed.

  • Implementing Compensation Capacitor in Logic CMOS Processes

    Tzu-Chao LIN  Jiin-Chuan WU  

     
    PAPER-Electronic Circuits

      Vol:
    E85-C No:8
      Page(s):
    1642-1650

    MOSFETs can be used as capacitors, but its capacitance can vary by 5 to 7 times as its terminal voltage varies. To reduce the voltage dependence of the capacitance, this paper proposed two types of devices: one is called accumulation MOSFET (AMOS) and the other is formed by two conventional PMOS connected in anti-parallel. These two devices are readily available in the standard digital CMOS processes. The proposed capacitors were implemented in three different CMOS processes. The measured results show that the capacitances of both devices have less voltage dependence than a single PMOS. The voltage dependence of the AMOS capacitance can be as small as 17%. The minimum capacitance per unit area of the AMOS is 1.8 times that of the double-poly capacitor in an analog/mixed-mode CMOS process. To verify the usefulness of these two types of capacitors, they are used as compensation capacitors in a conventional two-stage amplifier. The measured results show that the amplifier compensated by the AMOS capacitor has little variation (6%) of the unity-gain frequency over the input common-mode range. Due to its smaller die area and cheaper digital process, AMOS can be used as compensation capacitor without resorting to more expensive analog process.

  • New Results on the Boolean Functions That Can Be Expressed as the Sum of Two Bent Functions

    Longjiang QU  Shaojing FU  Qingping DAI  Chao LI  

     
    PAPER-Cryptography and Information Security

      Vol:
    E99-A No:8
      Page(s):
    1584-1590

    In this paper, we study the problem of a Boolean function can be represented as the sum of two bent functions. This problem was recently presented by N. Tokareva when studying the number of bent functions [27]. Firstly, several classes of functions, such as quadratic Boolean functions, Maiorana-MacFarland bent functions, many partial spread functions etc, are proved to be able to be represented as the sum of two bent functions. Secondly, methods to construct such functions from low dimension ones are also introduced. N. Tokareva's main hypothesis is proved for n≤6. Moreover, two hypotheses which are equivalent to N. Tokareva's main hypothesis are presented. These hypotheses may lead to new ideas or methods to solve this problem. Finally, necessary and sufficient conditions on the problem when the sum of several bent functions is again a bent function are given.

1-20hit(48hit)