電気学会論文誌C(電子・情報・システム部門誌)
Online ISSN : 1348-8155
Print ISSN : 0385-4221
ISSN-L : 0385-4221
126 巻 , 10 号
選択された号の論文の20件中1~20を表示しています
特集:ホームネットワーク
特集解説
  • 阪田 史郎, 松本 誠一郎
    2006 年 126 巻 10 号 p. 1192-1199
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    With the outstanding growth of communication and device technologies, various kinds of digital appliances have been introduced into home, and expectations toward home network which interconnects and controls such appliances have been rapidly emerging. This article describes the latest technologies and future trends on home network in which wireless network including wireless Personal Area Network (PAN) such as sensor network plays a vital role. The network includes wireless LAN, Ultra Wide Band (UWB), ZigBee sensor network and Power Line Communication (PLC). ECHONET which is a defacto standard for accommodating energy efficient legacy appliance control is also briefly introduced. As one of the key functions for seamless interconnection of digital appliances, protocol standardization is essential. This article addresses the defacto middleware architectures such as Universal Plug and Play (UPnP), Digital Living Networking Alliance (DLNA) and Open Service Gateway initiative (OSGi) which involve the standard protocols and message formats. Finally, seamless integration between in-house and outdoor networks, and in-house network interconnection between e.g. wireless LAN as a backbone and sensor network as a branch are presented as a future image of home network environment.
特集論文
<通信・ネットワーク>
  • 福島 誠治, 杉本 直登, 赤津 祐史, 界 義久, 小口 喜美夫
    2006 年 126 巻 10 号 p. 1200-1204
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    Toward the realization of fiber-to-the-desktop network, we have developed optical LAN card interfaces that are compatible with a PCMCIA interface of laptop PCs. This paper reports the structures and characteristics of the interfaces. Some applications are discussed, including office and home network.
  • 孫 均, 峯 俊郎, 小山 良, 倉嶋 利雄, 冨田 茂, 灰原 正
    2006 年 126 巻 10 号 p. 1205-1211
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    We have developed a new wiring system for home networks without the need to use a jointing tool or to deal with excess fiber length. Optical fiber curl cord is the key component of the system. This cord has a spiral structure, which makes it possible for the cord to stretch or contract without any loss increase. This is because it is made of a hole-assisted fiber with a low bending loss. We can employ this characteristic to realize a flexible wiring system. Optical fiber curl cord can be stretched considerably. For example, a cord with a curl length of 1 m and a curl diameter of 16 mm can be stretched to nearly 20 m. This means that we can use an optical fiber curl cord with a fixed length (here 1 m) to wire an optical home network of any length (here <20 m). To prove the feasibility of this idea, we undertook experiments where we installed optical fiber curl cord in ducts in various situations and created a calculation model to simulate wiring it through duct. This model worked well and we confirmed that it is possible to pull a 16 mm diameter curl cord with an SC connector through a 22 mm diameter pipe in any situation. And if we use this method to construct an optical home network, the workability will be greatly improved. This may be an effective way to reduce construction costs.
<ソフトウェア・情報処理>
  • 伊藤 誠悟, 河口 信夫
    2006 年 126 巻 10 号 p. 1212-1220
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    本論文では,既設の無線LANアクセスポイントと,既存の無線LANアダプタを用いて端末の位置推定を行う手法を提案する。 本手法では,位置推定を行う場所において各無線LANアクセスポイントからの電波強度を事前に測定し,ユーザはそれらを事前モデルとして保持する。 ユーザは事前モデルと現在ユーザが観測できる無線LANアクセスポイントの電波強度を用いて現在位置を推定する。 しかし,屋内環境において無線LANの受信電波強度はマルチパス等の影響により複雑に変化するため,位置推定を行う際に利用するアクセスポイントを適切に選択する必要がある。 本手法においては端末の位置推定時に,アクセスポイントを選択する段階と位置推定を行う段階の2段階に分けることにより,位置推定のために有用な情報を提供するアクセスポイントを選択し,選択されたアクセスポイントの情報を利用して位置推定を行う。 実験の結果,適切なアクセスポイントを選択し位置推定を行うことにより,位置推定精度の向上を確認したので報告する。 加えて,無線LANによる位置依存アプリケーションを紹介する。
論文
<電子・集積回路>
  • 佐々木 明彦, 阿部 公輝
    2006 年 126 巻 10 号 p. 1221-1228
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    Paul Kocher has proposed a cryptanalysis technique called Differential Power Analysis (DPA), in which attackers derive secret information such as private keys from a statistical analysis of the power consumption by the target device. There is now a demand to evaluate the DPA resistivity of cryptographic device before the device is actually created. In this paper, we focus on simulating DPA with high speed at algorithm level in upstream of the design process. Messerges used Power Leakage Model to obtain power consumption from Hamming Weight for proof of high-order DPA. However, the correctness of the model has not been verified. In this paper, we verify that difference of power consumption in DPA can be obtained from Power Leakage Model by investigating the cause of power consumption of CMOS circuits and transition probability of logic gates. The verification is performed by means of a circuit simulator. Next we describe a method of performing algorithm level simulation which calculates power consumption using Power Leakage Model. We illustrate the effectiveness of the method by applying it to DPA resistivity evaluation of DES implementation.
<医用電子・生体工学>
  • 齋藤 大輔, 斎藤 恵一, 斎藤 正男
    2006 年 126 巻 10 号 p. 1229-1234
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    Web site visibility has become important because of the rapid dissemination of World Wide Web, and combinations of foreground and background colors are crucial in providing high visibility. In our previous studies, the visibilities of several web-safe color combinations were examined using a psychological method. In those studies, simple stimuli were used because of experimental restriction. In this paper, legibility of sentences on web sites was examined using a psychophisiological method, point-of-regard measurement, to obtain other practical data. Ten people with normal color sensations ranging from ages 21 to 29 were recruited. The number of characters per line in each page was arranged in the same number, and the four representative achromatic web-safe colors, that is, #000000, #666666, #999999 and #CCCCCC, were examined. The reading time per character and the gaze time per line were obtained from point-of-regard measurement, and the normalized with the reading time and the gaze time of the three colors were calculated and compared. As the results, it was shown that the time of reading and gaze become long at the same ratio when the contrast decreases by point-of-regard measurement. Therefore, it was indicated that the legibility of color combinations could be estimated by point-of-regard measurement.
<音声画像処理・認識>
  • 松浦 佳史, 斉藤 文彦
    2006 年 126 巻 10 号 p. 1235-1241
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    This paper proposes a method to measure the two-dimensional pose of an object by using voting process based on geometrical and gray-leveled features between edge pixels and the base point. The proposed method can measure a location and an inclination of an object even if the object has a free pose in an image. In the template registration process, the geometrical features and the distribution of gray-levels for all edge pixels are registered into the template table. In the matching process, not only the geometrical features but also the arrays of gray-levels between the edge pixels and the base point are used for the matching. The experimental results show that the poses of objects with free locations and inclinations were recognized successfully by the proposed method. High speed matching was realized in comparison with the conventional methods.
  • Toshiyuki Tanaka, Yoshitaka Uchino, Teruaki Oka
    2006 年 126 巻 10 号 p. 1242-1248
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    Recently in Japan, pathologists have been in short supply, while each pathological diagnosis requires a substantial amount of time because each analyte must be inspected by multiple pathologists for adequate diagnosis. This paper deals with the classification method of gastric cancer and gastric adenoma, using image processing and pattern analysis. We first select the R component and G component from the RGB basis of the digital image, and the Y component from the YIQ basis for our system. After pre-processing, we automatically extracted the shape of the nucleus and cytoplasm. After many inspections, we selected 40 features for shape of the nucleus and cytoplasm and 14 features for texture within the cytoplasm for assessment of tumors. Principal component analysis, F test of homoscedasticity, t test of difference of average, stepwise method for selecting the smaller number of features, and discriminant method using Mahalanobis distance were all performed. Total ratio of diagnosis reached 96.9%, showing the validity of our proposed method.
<制御・計測>
<システム>
  • Xueqin Zhao, Jianming Lu, Yahagi Takashi
    2006 年 126 巻 10 号 p. 1255-1260
    発行日: 2006年
    公開日: 2007/01/01
    ジャーナル フリー
    The idea of combining both wavelets and neural networks has resulted in the formulation of wavelet network, whose basic functions are drawn from a family of orthonormal wavelets(1), which absorbs the advantage of high resolution of wavelets and the advantages of learning and feedforward of neural networks. The usual method to train wavelet networks is the backpropagation (BP) algorithm described by Rumelhart et al. However, this algorithm converges slowly for large or complex problems. In this paper, we propose to train wavelet network for nonlinear time series prediction by using the Unscented Kalman filter (UKF), which outperforms the conventional BP method and several other reference methods. Several simulation results are presented to validate the proposed method.
研究開発レター
<医用電子・生体工学>
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