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[Keyword] IT(16991hit)

261-280hit(16991hit)

  • An SOI-Based Lock-in Pixel with a Shallow Buried Channel for Reducing Parasitic Light Sensitivity and Improving Modulation Contrast

    Tatsuya KOBAYASHI  Keita YASUTOMI  Naoki TAKADA  Shoji KAWAHITO  

     
    PAPER

      Pubricized:
    2023/04/10
      Vol:
    E106-C No:10
      Page(s):
    538-545

    This paper presents a high-NIR sensitivity SOI-gate lock-in pixel with improved modulation contrast. The proposed pixel has a shallow buried channel and intermediate gates to create both a high lateral electric field and a potential barrier to parasitic light sensitivity. Device simulation results showed that parasitic light sensitivity reduced from 13.7% to 0.13% compared to the previous structure.

  • Nonvolatile Storage Cells Using FiCC for IoT Processors with Intermittent Operations

    Yuki ABE  Kazutoshi KOBAYASHI  Jun SHIOMI  Hiroyuki OCHI  

     
    PAPER

      Pubricized:
    2023/04/13
      Vol:
    E106-C No:10
      Page(s):
    546-555

    Energy harvesting has been widely investigated as a potential solution to supply power for Internet of Things (IoT) devices. Computing devices must operate intermittently rather than continuously, because harvested energy is unstable and some of IoT applications can be periodic. Therefore, processors for IoT devices with intermittent operation must feature a hibernation mode with zero-standby-power in addition to energy-efficient normal mode. In this paper, we describe the layout design and measurement results of a nonvolatile standard cell memory (NV-SCM) and nonvolatile flip-flops (NV-FF) with a nonvolatile memory using Fishbone-in-Cage Capacitor (FiCC) suitable for IoT processors with intermittent operations. They can be fabricated in any conventional CMOS process without any additional mask. NV-SCM and NV-FF are fabricated in a 180nm CMOS process technology. The area overhead by nonvolatility of a bit cell are 74% in NV-SCM and 29% in NV-FF, respectively. We confirmed full functionality of the NV-SCM and NV-FF. The nonvolatile system using proposed NV-SCM and NV-FF can reduce the energy consumption by 24.3% compared to the volatile system when hibernation/normal operation time ratio is 500 as shown in the simulation.

  • Experimental Exploration of the Backside ESD Impacts on an IC Chip in Flip Chip Packaging

    Takuya WADATSUMI  Kohei KAWAI  Rikuu HASEGAWA  Kikuo MURAMATSU  Hiromu HASEGAWA  Takuya SAWADA  Takahito FUKUSHIMA  Hisashi KONDO  Takuji MIKI  Makoto NAGATA  

     
    PAPER

      Pubricized:
    2023/04/13
      Vol:
    E106-C No:10
      Page(s):
    556-564

    This paper presents on-chip characterization of electrostatic discharge (ESD) impacts applied on the Si-substrate backside of a flip-chip mounted integrated circuit (FC-IC) chip. An FC-IC chip has an open backside and there is a threat of reliability problems and malfunctions caused by the backside ESD. We prepared a test FC-IC chip and measured Si-substrate voltage fluctuations on its frontside by an on-chip monitor (OCM) circuit. The voltage surges as large as 200mV were observed on the frontside when a 200-V ESD gun was irradiated through a 5kΩ contact resistor on the backside of a 350μm thick Si substrate. The distribution of voltage heights was experimentally measured at 20 on-chip locations among thinned Si substrates up to 40μm, and also explained in full-system level simulation of backside ESD impacts with the equivalent models of ESD-gun operation and FC-IC chip assembly.

  • An Analog Side-Channel Attack on a High-Speed Asynchronous SAR ADC Using Dual Neural Network Technique

    Ryozo TAKAHASHI  Takuji MIKI  Makoto NAGATA  

     
    BRIEF PAPER

      Pubricized:
    2023/04/13
      Vol:
    E106-C No:10
      Page(s):
    565-569

    This brief presents a side-channel attack (SCA) technique on a high-speed asynchronous successive approximation register (SAR) analog-to-digital converter (ADC). The proposed dual neural network based on multiple noise waveforms separately discloses sign and absolute value information of input signals which are hidden by the differential structure and high-speed asynchronous operation. The target SAR ADC and on-chip noise monitors are designed on a single prototype chip for SCA demonstration. Fabricated in 40 nm, the experimental results show the proposed attack on the asynchronous SAR ADC successfully restores the input data with a competitive accuracy within 300 mV rms error.

  • Hybrid, Asymmetric and Reconfigurable Input Unit Designs for Energy-Efficient On-Chip Networks

    Xiaoman LIU  Yujie GAO  Yuan HE  Xiaohan YUE  Haiyan JIANG  Xibo WANG  

     
    PAPER

      Pubricized:
    2023/04/10
      Vol:
    E106-C No:10
      Page(s):
    570-579

    The complexity and scale of Networks-on-Chip (NoCs) are growing as more processing elements and memory devices are implemented on chips. However, under strict power budgets, it is also critical to lower the power consumption of NoCs for the sake of energy efficiency. In this paper, we therefore present three novel input unit designs for on-chip routers attempting to shrink their power consumption while still conserving the network performance. The key idea behind our designs is to organize buffers in the input units with characteristics of the network traffic in mind; as in our observations, only a small portion of the network traffic are long packets (composed of multiple flits), which means, it is fair to implement hybrid, asymmetric and reconfigurable buffers so that they are mainly targeting at short packets (only having a single flit), hence the smaller power consumption and area overhead. Evaluations show that our hybrid, asymmetric and reconfigurable input unit designs can achieve an average reduction of energy consumption per flit by 45%, 52.3% and 56.2% under 93.6% (for hybrid designs) and 66.3% (for asymmetric and reconfigurable designs) of the original router area, respectively. Meanwhile, we only observe minor degradation in network latency (ranging from 18.4% to 1.5%, on average) with our proposals.

  • Contact Pad Design Considerations for Semiconductor Qubit Devices for Reducing On-Chip Microwave Crosstalk

    Kaito TOMARI  Jun YONEDA  Tetsuo KODERA  

     
    BRIEF PAPER

      Pubricized:
    2023/02/20
      Vol:
    E106-C No:10
      Page(s):
    588-591

    Reducing on-chip microwave crosstalk is crucial for semiconductor spin qubit integration. Toward crosstalk reduction and qubit integration, we investigate on-chip microwave crosstalk for gate electrode pad designs with (i) etched trenches between contact pads or (ii) contact pads with reduced sizes. We conclude that the design with feature (ii) is advantageous for high-density integration of semiconductor qubits with small crosstalk (below -25 dB at 6 GHz), favoring the introduction of flip-chip bonding.

  • Single-Electron Transistor Operation of a Physically Defined Silicon Quantum Dot Device Fabricated by Electron Beam Lithography Employing a Negative-Tone Resist

    Shimpei NISHIYAMA  Kimihiko KATO  Yongxun LIU  Raisei MIZOKUCHI  Jun YONEDA  Tetsuo KODERA  Takahiro MORI  

     
    BRIEF PAPER

      Pubricized:
    2023/06/02
      Vol:
    E106-C No:10
      Page(s):
    592-596

    We have proposed and demonstrated a device fabrication process of physically defined quantum dots utilizing electron beam lithography employing a negative-tone resist toward high-density integration of silicon quantum bits (qubits). The electrical characterization at 3.8K exhibited so-called Coulomb diamonds, which indicates successful device operation as single-electron transistors. The proposed device fabrication process will be useful due to its high compatibility with the large-scale integration process.

  • Feedback Node Sets in Pancake Graphs and Burnt Pancake Graphs

    Sinyu JUNG  Keiichi KANEKO  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2023/06/30
      Vol:
    E106-D No:10
      Page(s):
    1677-1685

    A feedback node set (FNS) of a graph is a subset of the nodes of the graph whose deletion makes the residual graph acyclic. By finding an FNS in an interconnection network, we can set a check point at each node in it to avoid a livelock configuration. Hence, to find an FNS is a critical issue to enhance the dependability of a parallel computing system. In this paper, we propose a method to find FNS's in n-pancake graphs and n-burnt pancake graphs. By analyzing the types of cycles proposed in our method, we also give the number of the nodes in the FNS in an n-pancake graph, (n-2.875)(n-1)!+1.5(n-3)!, and that in an n-burnt pancake graph, 2n-1(n-1)!(n-3.5).

  • GPU-Accelerated Estimation and Targeted Reduction of Peak IR-Drop during Scan Chain Shifting

    Shiling SHI  Stefan HOLST  Xiaoqing WEN  

     
    PAPER-Dependable Computing

      Pubricized:
    2023/07/07
      Vol:
    E106-D No:10
      Page(s):
    1694-1704

    High power dissipation during scan test often causes undue yield loss, especially for low-power circuits. One major reason is that the resulting IR-drop in shift mode may corrupt test data. A common approach to solving this problem is partial-shift, in which multiple scan chains are formed and only one group of scan chains is shifted at a time. However, existing partial-shift based methods suffer from two major problems: (1) their IR-drop estimation is not accurate enough or computationally too expensive to be done for each shift cycle; (2) partial-shift is hence applied to all shift cycles, resulting in long test time. This paper addresses these two problems with a novel IR-drop-aware scan shift method, featuring: (1) Cycle-based IR-Drop Estimation (CIDE) supported by a GPU-accelerated dynamic power simulator to quickly find potential shift cycles with excessive peak IR-drop; (2) a scan shift scheduling method that generates a scan chain grouping targeted for each considered shift cycle to reduce the impact on test time. Experiments on ITC'99 benchmark circuits show that: (1) the CIDE is computationally feasible; (2) the proposed scan shift schedule can achieve a global peak IR-drop reduction of up to 47%. Its scheduling efficiency is 58.4% higher than that of an existing typical method on average, which means our method has less test time.

  • Fault-Resilient Robot Operating System Supporting Rapid Fault Recovery with Node Replication

    Jonghyeok YOU  Heesoo KIM  Kilho LEE  

     
    LETTER-Software System

      Pubricized:
    2023/07/07
      Vol:
    E106-D No:10
      Page(s):
    1742-1746

    This paper proposes a fault-resilient ROS platform supporting rapid fault detection and recovery. The platform employs heartbeat-based fault detection and node replication-based recovery. Our prototype implementation on top of the ROS Melodic shows a great performance in evaluations with a Nvidia development board and an inverted pendulum device.

  • Prior Information Based Decomposition and Reconstruction Learning for Micro-Expression Recognition

    Jinsheng WEI  Haoyu CHEN  Guanming LU  Jingjie YAN  Yue XIE  Guoying ZHAO  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2023/07/13
      Vol:
    E106-D No:10
      Page(s):
    1752-1756

    Micro-expression recognition (MER) draws intensive research interest as micro-expressions (MEs) can infer genuine emotions. Prior information can guide the model to learn discriminative ME features effectively. However, most works focus on researching the general models with a stronger representation ability to adaptively aggregate ME movement information in a holistic way, which may ignore the prior information and properties of MEs. To solve this issue, driven by the prior information that the category of ME can be inferred by the relationship between the actions of facial different components, this work designs a novel model that can conform to this prior information and learn ME movement features in an interpretable way. Specifically, this paper proposes a Decomposition and Reconstruction-based Graph Representation Learning (DeRe-GRL) model to efectively learn high-level ME features. DeRe-GRL includes two modules: Action Decomposition Module (ADM) and Relation Reconstruction Module (RRM), where ADM learns action features of facial key components and RRM explores the relationship between these action features. Based on facial key components, ADM divides the geometric movement features extracted by the graph model-based backbone into several sub-features, and learns the map matrix to map these sub-features into multiple action features; then, RRM learns weights to weight all action features to build the relationship between action features. The experimental results demonstrate the effectiveness of the proposed modules, and the proposed method achieves competitive performance.

  • Mitigate: Toward Comprehensive Research and Development for Analyzing and Combating IoT Malware

    Koji NAKAO  Katsunari YOSHIOKA  Takayuki SASAKI  Rui TANABE  Xuping HUANG  Takeshi TAKAHASHI  Akira FUJITA  Jun'ichi TAKEUCHI  Noboru MURATA  Junji SHIKATA  Kazuki IWAMOTO  Kazuki TAKADA  Yuki ISHIDA  Masaru TAKEUCHI  Naoto YANAI  

     
    INVITED PAPER

      Pubricized:
    2023/06/08
      Vol:
    E106-D No:9
      Page(s):
    1302-1315

    In this paper, we developed the latest IoT honeypots to capture IoT malware currently on the loose, analyzed IoT malware with new features such as persistent infection, developed malware removal methods to be provided to IoT device users. Furthermore, as attack behaviors using IoT devices become more diverse and sophisticated every year, we conducted research related to various factors involved in understanding the overall picture of attack behaviors from the perspective of incident responders. As the final stage of countermeasures, we also conducted research and development of IoT malware disabling technology to stop only IoT malware activities in IoT devices and IoT system disabling technology to remotely control (including stopping) IoT devices themselves.

  • Enumerating Empty and Surrounding Polygons

    Shunta TERUI  Katsuhisa YAMANAKA  Takashi HIRAYAMA  Takashi HORIYAMA  Kazuhiro KURITA  Takeaki UNO  

     
    PAPER-Algorithms and Data Structures

      Pubricized:
    2023/04/03
      Vol:
    E106-A No:9
      Page(s):
    1082-1091

    We are given a set S of n points in the Euclidean plane. We assume that S is in general position. A simple polygon P is an empty polygon of S if each vertex of P is a point in S and every point in S is either outside P or a vertex of P. In this paper, we consider the problem of enumerating all the empty polygons of a given point set. To design an efficient enumeration algorithm, we use a reverse search by Avis and Fukuda with child lists. We propose an algorithm that enumerates all the empty polygons of S in O(n2|ε(S)|)-time, where ε(S) is the set of empty polygons of S. Moreover, by applying the same idea to the problem of enumerating surrounding polygons of a given point set S, we propose an enumeration algorithm that enumerates them in O(n2)-delay, while the known algorithm enumerates in O(n2 log n)-delay, where a surroundingpolygon of S is a polygon such that each vertex of the polygon is a point in S and every point in S is either inside the polygon or a vertex of the polygon.

  • Convex Grid Drawings of Internally Triconnected Plane Graphs with Pentagonal Contours

    Kazuyuki MIURA  

     
    PAPER-Algorithms and Data Structures

      Pubricized:
    2023/03/06
      Vol:
    E106-A No:9
      Page(s):
    1092-1099

    In a convex grid drawing of a plane graph, all edges are drawn as straight-line segments without any edge-intersection, all vertices are put on grid points and all facial cycles are drawn as convex polygons. A plane graph G has a convex drawing if and only if G is internally triconnected, and an internally triconnected plane graph G has a convex grid drawing on an (n-1) × (n-1) grid if either G is triconnected or the triconnected component decomposition tree T(G) of G has two or three leaves, where n is the number of vertices in G. An internally triconnected plane graph G has a convex grid drawing on a 2n × 2n grid if T(G) has exactly four leaves. Furthermore, an internally triconnected plane graph G has a convex grid drawing on a 20n × 16n grid if T(G) has exactly five leaves. In this paper, we show that an internally triconnected plane graph G has a convex grid drawing on a 10n × 5n grid if T(G) has exactly five leaves. We also present a linear-time algorithm to find such a drawing.

  • Optimal Online Bin Packing Algorithms for Some Cases with Two Item Sizes

    Hiroshi FUJIWARA  Masaya KAWAGUCHI  Daiki TAKIZAWA  Hiroaki YAMAMOTO  

     
    PAPER-Algorithms and Data Structures

      Pubricized:
    2023/03/07
      Vol:
    E106-A No:9
      Page(s):
    1100-1110

    The bin packing problem is a problem of finding an assignment of a sequence of items to a minimum number of bins, each of capacity one. An online algorithm for the bin packing problem is an algorithm that irrevocably assigns each item one by one from the head of the sequence. Gutin, Jensen, and Yeo (2006) considered a version in which all items are only of two different sizes and the online algorithm knows the two possible sizes in advance, and gave an optimal online algorithm for the case when the larger size exceeds 1/2. In this paper we provide an optimal online algorithm for some of the cases when the larger size is at most 1/2, on the basis of a framework that facilitates the design and analysis of algorithms.

  • Efficient Supersingularity Testing of Elliptic Curves Using Legendre Curves

    Yuji HASHIMOTO  Koji NUIDA  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2023/03/07
      Vol:
    E106-A No:9
      Page(s):
    1119-1130

    There are two types of elliptic curves, ordinary elliptic curves and supersingular elliptic curves. In 2012, Sutherland proposed an efficient and almost deterministic algorithm for determining whether a given curve is ordinary or supersingular. Sutherland's algorithm is based on sequences of isogenies started from the input curve, and computation of each isogeny requires square root computations, which is the dominant cost of the algorithm. In this paper, we reduce this dominant cost of Sutherland's algorithm to approximately a half of the original. In contrast to Sutherland's algorithm using j-invariants and modular polynomials, our proposed algorithm is based on Legendre form of elliptic curves, which simplifies the expression of each isogeny. Moreover, by carefully selecting the type of isogenies to be computed, we succeeded in gathering square root computations at two consecutive steps of Sutherland's algorithm into just a single fourth root computation (with experimentally almost the same cost as a single square root computation). The results of our experiments using Magma are supporting our argument; for cases of characteristic p of 768-bit to 1024-bit lengths, our proposed algorithm for characteristic p≡1 (mod 4) runs in about 61.5% of the time and for characteristic p≡3 (mod 4) also runs in about 54.9% of the time compared to Sutherland's algorithm.

  • Post-Quantum Anonymous One-Sided Authenticated Key Exchange without Random Oracles

    Ren ISHIBASHI  Kazuki YONEYAMA  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2023/03/13
      Vol:
    E106-A No:9
      Page(s):
    1141-1163

    Authenticated Key Exchange (AKE) is a cryptographic protocol to share a common session key among multiple parties. Usually, PKI-based AKE schemes are designed to guarantee secrecy of the session key and mutual authentication. However, in practice, there are many cases where mutual authentication is undesirable such as in anonymous networks like Tor and Riffle, or difficult to achieve due to the certificate management at the user level such as the Internet. Goldberg et al. formulated a model of anonymous one-sided AKE which guarantees the anonymity of the client by allowing only the client to authenticate the server, and proposed a concrete scheme. However, existing anonymous one-sided AKE schemes are only known to be secure in the random oracle model. In this paper, we propose generic constructions of anonymous one-sided AKE in the random oracle model and in the standard model, respectively. Our constructions allow us to construct the first post-quantum anonymous one-sided AKE scheme from isogenies in the standard model.

  • Forward Secure Message Franking with Updatable Reporting Tags

    Hiroki YAMAMURO  Keisuke HARA  Masayuki TEZUKA  Yusuke YOSHIDA  Keisuke TANAKA  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2023/03/07
      Vol:
    E106-A No:9
      Page(s):
    1164-1176

    Message franking is introduced by Facebook in end-to-end encrypted messaging services. It allows to produce verifiable reports of malicious messages by including cryptographic proofs, called reporting tags, generated by Facebook. Recently, Grubbs et al. (CRYPTO'17) proceeded with the formal study of message franking and introduced committing authenticated encryption with associated data (CAEAD) as a core primitive for obtaining message franking. In this work, we aim to enhance the security of message franking and introduce forward security and updates of reporting tags for message franking. Forward security guarantees the security associated with the past keys even if the current keys are exposed and updates of reporting tags allow for reporting malicious messages after keys are updated. To this end, we firstly propose the notion of key-evolving message franking with updatable reporting tags including additional key and reporting tag update algorithms. Then, we formalize five security requirements: confidentiality, ciphertext integrity, unforgeability, receiver binding, and sender binding. Finally, we show a construction of forward secure message franking with updatable reporting tags based on CAEAD, forward secure pseudorandom generator, and updatable message authentication code.

  • Fault-Tolerant Aggregate Signature Schemes against Bandwidth Consumption Attack

    Kyosuke YAMASHITA  Ryu ISHII  Yusuke SAKAI  Tadanori TERUYA  Takahiro MATSUDA  Goichiro HANAOKA  Kanta MATSUURA  Tsutomu MATSUMOTO  

     
    PAPER-Cryptography and Information Security

      Pubricized:
    2023/04/03
      Vol:
    E106-A No:9
      Page(s):
    1177-1188

    A fault-tolerant aggregate signature (FT-AS) scheme is a variant of an aggregate signature scheme with the additional functionality to trace signers that create invalid signatures in case an aggregate signature is invalid. Several FT-AS schemes have been proposed so far, and some of them trace such rogue signers in multi-rounds, i.e., the setting where the signers repeatedly send their individual signatures. However, it has been overlooked that there exists a potential attack on the efficiency of bandwidth consumption in a multi-round FT-AS scheme. Since one of the merits of aggregate signature schemes is the efficiency of bandwidth consumption, such an attack might be critical for multi-round FT-AS schemes. In this paper, we propose a new multi-round FT-AS scheme that is tolerant of such an attack. We implement our scheme and experimentally show that it is more efficient than the existing multi-round FT-AS scheme if rogue signers randomly create invalid signatures with low probability, which for example captures spontaneous failures of devices in IoT systems.

  • A Fast Algorithm for Finding a Maximal Common Subsequence of Multiple Strings

    Miyuji HIROTA  Yoshifumi SAKAI  

     
    LETTER-Algorithms and Data Structures

      Pubricized:
    2023/03/06
      Vol:
    E106-A No:9
      Page(s):
    1191-1194

    For any m strings of total length n, we propose an O(mn log n)-time, O(n)-space algorithm that finds a maximal common subsequence of all the strings, in the sense that inserting any character in it no longer yields a common subsequence of them. Such a common subsequence could be treated as indicating a nontrivial common structure we could find in the strings since it is NP-hard to find any longest common subsequence of the strings.

261-280hit(16991hit)