著者

Cong ZHOU Jing TAO Baosheng WANG Na ZHAO

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Communications (ISSN:09168516)

巻号頁・発行日

vol.E106-B, no.3, pp.230-240, 2023-03-01

---

As a key technology of 5G, NFV has attracted much attention. In addition, monitoring plays an important role, and can be widely used for virtual network function placement and resource optimisation. The existing monitoring methods focus on the monitoring load without considering they own resources needed. This raises a unique challenge: jointly optimising the NFV monitoring systems and minimising their monitoring load at runtime. The objective is to enhance the gain in real-time monitoring metrics at minimum monitoring costs. In this context, we propose a novel NFV monitoring solution, namely, iMon (Monitoring by inferring), that jointly optimises the monitoring process and reduces resource consumption. We formalise the monitoring process into a multitarget regression problem and propose three regression models. These models are implemented by a deep neural network, and an experimental platform is built to prove their availability and effectiveness. Finally, experiments also show that monitoring resource requirements are reduced, and the monitoring load is just 0.6% of that of the monitoring tool cAdvisor on our dataset.

著者

Ouyang JUNJIE Naoto YANAI Tatsuya TAKEMURA Masayuki OKADA Shingo OKAMURA Jason Paul CRUZ

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

vol.E106-A, no.3, pp.170-184, 2023-03-01

被引用文献数

1

---

The BGPsec protocol, which is an extension of the border gateway protocol (BGP) for Internet routing known as BGPsec, uses digital signatures to guarantee the validity of routing information. However, the use of digital signatures in routing information on BGPsec causes a lack of memory in BGP routers, creating a gaping security hole in today's Internet. This problem hinders the practical realization and implementation of BGPsec. In this paper, we present APVAS (AS path validation based on aggregate signatures), a new protocol that reduces the memory consumption of routers running BGPsec when validating paths in routing information. APVAS relies on a novel aggregate signature scheme that compresses individually generated signatures into a single signature. Furthermore, we implement a prototype of APVAS on BIRD Internet Routing Daemon and demonstrate its efficiency on actual BGP connections. Our results show that the routing tables of the routers running BGPsec with APVAS have 20% lower memory consumption than those running the conventional BGPsec. We also confirm the effectiveness of APVAS in the real world by using 800,000 routes, which are equivalent to the full route information on a global scale.

著者

Kotaro NAGANO Masahiro KAWANO Yuhei NAGAO Hiroshi OCHI

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

vol.E106-A, no.3, pp.456-463, 2023-03-01

---

Cancellation of self interference (SI) is an important technology in order for wireless communication system devices to perform full-duplex communication. In this paper, we propose a novel self-interference cancellation using null beamforming to be applied entire IEEE 802.11 frame including the legacy part for full-duplex wireless communication on Cooperative MIMO (Multiple Input Multiple Output). We evaluate the SI cancellation amount by the proposed method using a field programmable gate array (FPGA) and software defined radio (SDR), and show the experimental results. In the experiment, it is confirmed that the amount of SI cancellation by the proposed method was at least 18dB. The SI cancellation amount can be further potentiated with more accurate CSI (channel state information) by increasing the transmission power. It is shown that SI can be suppressed whole frame which includes legacy preamble part. The proposed method can be applied to next generation wireless communication standards as well.

著者

Daiki SAITO Jeyeon KIM Tetsuya MANABE

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

pp.2022EAP1027, (Released:2022-09-06)

---

Currently, the proportion of independent travel is increasing in Japan. Therefore, earlier studies supporting itinerary planning have been presented. However, these studies have only insufficiently considered rural tourism. For example, tourist often use public transportation during trips in rural areas, although it is often difficult for a tourist to plan an itinerary for public transportation. Even if an itinerary can be planned, it will entail long waiting times at the station or bus stop. Nevertheless, earlier studies have only insufficiently considered these elements in itinerary planning. On the other hand, navigation is necessary in addition to itinerary creation. Particularly, recent navigation often considers dynamic information. During trips using public transportation, schedule changes are important dynamic information. For example, tourist arrive at bus stop earlier than planned. In such case, the waiting time will be longer than the waiting time included in the itinerary. In contrast, if a person is running behind schedule, a risk arises of missing bus. Nevertheless, earlier studies have only insufficiently considered these schedule changes. In this paper, we construct a tourism application that considers the waiting time to improve the tourism experience in rural areas. We define waiting time using static waiting time and dynamic waiting time. Static waiting time is waiting time that is included in the itinerary. Dynamic waiting time is the waiting time that is created by schedule changes during a trip. With this application, static waiting times is considered in the planning function. The dynamic waiting time is considered in the navigation function. To underscore the effectiveness of this application, experiments of the planning function and experiments of the navigation function is conducted in Tsuruoka City, Yamagata Prefecture. Based on the results, we confirmed that a tourist can readily plan a satisfactory itinerary using the planning function. Additionally, we confirmed that Navigation function can use waiting times effectively by suggesting additional tourist spots.

著者

Yan Ding Xiaoxin Liang Yuepeng Yan Xiao Wang

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Electronics Express (ISSN:13492543)

巻号頁・発行日

vol.20, no.3, pp.20220526, 2023-02-10 (Released:2023-02-10)

参考文献数

30

被引用文献数

1

---

A comprehensive study of air core recta-coax line (ARCL) based on MEMS surface micromachining technology is presented in this paper. The ARCL-to-semi-rectangular coaxial transmission line (SCL) ground-signal-ground (GSG) transition is proposed and designed for probe testing and integration with MMIC chips. To obtain the characteristic impedance of SCL, an equivalent model and theoretical derivation process is presented. In order to consider the effects of processing on performance, electrical effects of dielectric support strap parameters and potential fabrication issues including offset layers and over etching are investigated. For verification, the back-to-back GSG transition is fabricated and measured which has a low insertion loss of 0.13dB up to 50GHz, and a return loss better than -23dB within 5-50GHz. As an example, a demonstration of ARCL with GSG transition for MMIC chips integration is demonstrated.

著者

Maki Arai Takana Kaho

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Communications Express (ISSN:21870136)

巻号頁・発行日

vol.12, no.2, pp.48-53, 2023-02-01 (Released:2023-02-01)

参考文献数

14

---

In this paper, we describe a novel 3-D Luneburg lens using radial holes. A Luneburg lens can suppress the side lobe of the antenna and increase the gain. The prototype Luneburg lens was fabricated using a 30mm radius dielectric sphere with uniform permittivity by 2.1 and many holes by 1mm radius, called radial holes drilled vertically on the sphere surface. The relative permittivity distribution of the Luneburg lens is realized by changing the number and depth of five types of holes. To confirm the effectiveness of the fabricated Luneburg lens, the far-field radiation pattern at 25GHz was measured using a flanged rectangular waveguide as a wave source. It achieved a high gain of 22.4dBi. The measured radiation pattern generally agreed well with the theoretical radiation pattern of the Luneburg lens, and the validity of the Luneburg lens with radial holes at the quasi-millimeter wave was confirmed. It can be used for beam steering in 5G/6G base stations.

著者

堤 瑛美子 郭 亦鳴 植野 真臣

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

電子情報通信学会論文誌 D (ISSN:18804535)

巻号頁・発行日

vol.J106-D, no.2, pp.72-83, 2023-02-01

---

近年,教育現場ではオンラインラーニングシステムで収集された教育ビッグデータをいかに有効に活用するかが課題となっている.人工知能分野では,これらの教育ビッグデータに機械学習手法を適用し,学習者の課題への反応を予測することにより,学習者への適切な支援を行うアダプティブラーニングが注目されている.Tsutsumiら(2021)はアダプティブラーニングのために深層学習手法と項目反応理論を組み合わせ,パラメータの解釈性をもちながら高精度な反応予測を可能とするDeepIRTを開発し,高い予測精度とパラメータの解釈性を実現している.しかし,DeepIRTでは学習者の潜在的な能力値を推定する際に最新の学習データのみを用いるために,過去の学習データを十分に反映できていない可能性がある.本研究では,DeepIRTに新たなHypernetworkを組み合わせ,学習者の過去の学習データと最新の学習データの重要性を推定することで両者のバランスを最適化しながら能力値推定を行う.評価実験では,提案手法が最先端の反応予測手法を上回る反応予測精度を示した.

著者

Jing ZHANG Dan LI Hong-an LI Xuewen LI Lizhi ZHANG

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Information and Systems (ISSN:09168532)

巻号頁・発行日

vol.E106-D, no.2, pp.229-239, 2023-02-01

---

In order to solve the low-quality problems such as low brightness, poor contrast, noise interference and color imbalance in night images, a night image enhancement algorithm based on MDIFE-Net curve estimation is presented. This algorithm mainly consists of three parts: Firstly, we design an illumination estimation curve (IEC), which adjusts the pixel level of the low illumination image domain through a non-linear fitting function, maps to the enhanced image domain, and effectively eliminates the effect of illumination loss; Secondly, the DCE-Net is improved, replacing the original Relu activation function with a smoother Mish activation function, so that the parameters can be better updated; Finally, illumination estimation loss function, which combines image attributes with fidelity, is designed to drive the no-reference image enhancement, which preserves more image details while enhancing the night image. The experimental results show that our method can not only effectively improve the image contrast, but also make the details of the target more prominent, improve the visual quality of the image, and make the image achieve a better visual effect. Compared with four existing low illumination image enhancement algorithms, the NIQE and STD evaluation index values are better than other representative algorithms, verify the feasibility and validity of the algorithm, and verify the rationality and necessity of each component design through ablation experiments.

著者

岩名 紘基 重宗 宏毅 澤田 秀之

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

電子情報通信学会論文誌 C (ISSN:13452827)

巻号頁・発行日

vol.J106-C, no.2, pp.79-85, 2023-02-01

---

形状記憶合金(Shape-Memory Alloy: SMA)は,温度変化により相変態を起こすことで,記憶した形状に回復する合金である.この合金は,人工筋肉やばねのように様々な形で応用されている.従来のSMAアクチュエータは時間に対して緩やかに変形するものに応用されてきた.我々はこれまでに,SMAワイヤにパルス電圧を流すことによる数百Hzまでの振動現象を発見し,これを応用した微小振動アクチュエータを提案してきた.しかし,この現象の特性や原理については,未だ解明されていない点が多い.本研究ではSMAワイヤの振動現象の解明及び特性の理解のために,有限要素法を用いたシミュレーションと実際の振動現象の測定を行った.振動現象において,その振幅は幾つかの物理パラメータが寄与しており,これらを変化させると振幅のピークが変化することがわかった.この特性を応用することにより,SMAアクチュエータの効果的な利用が可能となる.

著者

Yang XIAO Zhongyuan ZHOU Changping TANG Jinjing REN Mingjie SHENG Zhengrui XU

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Electronics (ISSN:09168516)

巻号頁・発行日

vol.E106-C, no.2, pp.41-49, 2023-02-01

被引用文献数

1

---

This paper first introduces the structure of a shipboard equipment control cabinet and the preliminary design of electromagnetic shielding, then introduces the principle of low-frequency magnetic field shielding, and uses silicon steel sheet to shield the low-frequency magnetic field of shipboard equipment control equipment. Based on ANSYS Maxwell simulation software, the low-frequency magnetic field radiation emission of the equipment's conducted harmonic peak frequency point is simulated. Finally, according to MIL-STD-461G test standard, the low-frequency magnetic field radiation emission test is carried out, which meets the limit requirements of the standard. The low-frequency magnetic field shielding technology has practical value. The low-frequency magnetic field radiation emission simulation based on ANSYS Maxwell proposed in this paper is a useful attempt for the quantitative simulation of radiation emission.

著者

吉田 政望 ガジェゴス ラモネト アルベルト 野口 拓

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

電子情報通信学会論文誌 B (ISSN:13444697)

巻号頁・発行日

vol.J106-B, no.1, pp.13-26, 2023-01-01

---

アドホックネットワークでは,端末が使用できる電池容量や周波数帯域などの資源が有限である.アドホックネットワークにおいてブロードキャスト通信を行う場合,これらの資源の効率的な利用が求められる.不要なパケットを削減しネットワーク資源の浪費を抑えるための技術としてネットワークコーディングがある.ネットワークコーディングのパケット削減効果はネットワークトポロジーに依存する.本論文では,アドホックネットワークにおいてネットワークコーディングを用いる場合,ネットワークコーディングを適用可能なネットワークトポロジーであるかを判定し,効率的なブロードキャストを実現する方法を提案する.提案方式では,隣接ノードの移動性に応じてパケット転送方式を通常送信若しくはネットワークコーディングの間で動的に切り替えることで,パケット配送率の低下を抑えながらネットワーク全体のパケット数を削減することができる.計算機シミュレーションによる実験を行い,通常送信及びネットワークコーディングのみの場合,確率的ネットワークコーディングの場合と比較して,提案方式は効率的なパケット配送が可能であることを明らかにした.

著者

Sai YAO Daichi KITAHARA Hiroki KURODA Akira HIRABAYASHI

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

vol.E106-A, no.2, pp.106-123, 2023-02-01

---

The mean, median, and mode are usually calculated from univariate observations as the most basic representative values of a random variable. To measure the spread of the distribution, the standard deviation, interquartile range, and modal interval are also calculated. When we analyze continuous relations between a pair of random variables from bivariate observations, regression analysis is often used. By minimizing appropriate costs evaluating regression errors, we estimate the conditional mean, median, and mode. The conditional standard deviation can be estimated if the bivariate observations are obtained from a Gaussian process. Moreover, the conditional interquartile range can be calculated for various distributions by the quantile regression that estimates any conditional quantile (percentile). Meanwhile, the study of the modal interval regression is relatively new, and spline regression models, known as flexible models having the optimality on the smoothness for bivariate data, are not yet used. In this paper, we propose a modal interval regression method based on spline quantile regression. The proposed method consists of two steps. In the first step, we divide the bivariate observations into bins for one random variable, then detect the modal interval for the other random variable as the lower and upper quantiles in each bin. In the second step, we estimate the conditional modal interval by constructing both lower and upper quantile curves as spline functions. By using the spline quantile regression, the proposed method is widely applicable to various distributions and formulated as a convex optimization problem on the coefficient vectors of the lower and upper spline functions. Extensive experiments, including settings of the bin width, the smoothing parameter and weights in the cost function, show the effectiveness of the proposed modal interval regression in terms of accuracy and visual shape for synthetic data generated from various distributions. Experiments for real-world meteorological data also demonstrate a good performance of the proposed method.

著者

Jiazhe Li Rui Li Huanting Lu

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Electronics Express (ISSN:13492543)

巻号頁・発行日

vol.20, no.2, pp.20210501, 2023-01-25 (Released:2023-01-25)

参考文献数

30

---

This paper introduces a method to achieve fast scanning power supply for Proton Therapy. To meet the specific needs of this power supply, a new structure consists of dynamic module (high voltage part) and static module (low voltage part) has been designed and tested. The simulation results and actual waveform were listed in this paper. The results showed that the current rising slope can reach 90kA/s.

著者

Sooyol Ok Suk-Hwan Lee

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

Nonlinear Theory and Its Applications, IEICE (ISSN:21854106)

巻号頁・発行日

vol.14, no.1, pp.2-17, 2023 (Released:2023-01-01)

参考文献数

29

被引用文献数

1

---

This paper proposes a technique for 360-degree panoramic video generating with multiple actual and virtual cameras in real-time. Our method acquires multiple images consisting of real images from physical cameras and virtual images from virtual cameras by GPU-based texture and encoding. Then, our method generates 360-degree panoramic images by ORB feature detection and matching to virtual and real images, automatic homography estimation based on the random absent consensus algorithm, multi-band blending and produces high-resolution video stream by Nvidia encoder based Hardware accelerated video encoding. From experimental results, we verified that our method takes at least 45fps at 2K resolution and 33fps at 4K resolution when transmitting the head mounted display stereo, enabling real-time 360-degree panoramic video generation as well as transmission.

著者

朝日 南々香 竹内 勇剛

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

電子情報通信学会論文誌 D (ISSN:18804535)

巻号頁・発行日

vol.J106-D, no.1, pp.2-13, 2023-01-01

---

対人インタラクションにおける身体接触は,被接触者に精神的安泰をもたらしたり,向社会的行動を促進する効果があることが明らかになっており,このような身体接触はソーシャルタッチと呼ばれている.本研究では,ロボットが作業課題の遂行を依頼する状況下において,ロボットの接触のタイミングの統制が2名の実験参加者の協力行動に及ぼす効果を明らかにするため,2人1組の19ペアを対象に同期条件/非同期条件/非接触条件の3条件からなるインタラクション実験を行った.実験は,ロボットが作業課題の依頼とともに身体接触を行い,その後実験参加者の2名1組のペアとなって作業課題を行うものである.実験の結果,ペアに対するロボットの同期的な接触が,非同期的な接触や接触しない場合に比べ,統計的有意に実験参加者の協力行動を促進させることが明らかになった.一方で,ロボットの身体接触は,実験参加者のペアとなった相手及びロボットに対する印象には影響しなかった.これらの結果から,ロボットによるソーシャルタッチはインタラクションにおける時間的構造が関与している可能性が示唆され,二者に対する同期的な身体接触は,人同士の協力行動を促進するために有効であることが示された.

著者

本多 亮也 阿部 晋士 大平 孝

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

電子情報通信学会論文誌 C (ISSN:13452827)

巻号頁・発行日

vol.J106-C, no.1, pp.20-29, 2023-01-01

---

入力電力が異なる二つの高周波整流回路の合成動作において片方の高周波整流回路が動作しなくなるカットオフ現象について定量的に考察する.合成動作を解析する準備として,単体動作において高周波整流回路がカットオフする条件を導出する.カットオフ条件となる特定の出力電圧と流通角の値を導出する.この二つの特定の値を用いて,合成動作におけるカットオフ現象の理論解析を行う.結果,入力電力が小さい方の高周波整流回路がカットオフする入力電力比を発見し,定式化した.カットオフが起きる入力電力比は,入力電力が小さい方の高周波整流回路に関係なく,入力電力が大きい方の流通角のみで決まることを発見した.導出した理論を数値解析(ハーモニックバランスシミュレーション)と実機実験(6.78 MHz, 100 W)の両方で検証し,理論とよく一致していることを示した.

著者

Tatsuya KOYAKUMARU Masahiro YUKAWA Eduardo PAVEZ Antonio ORTEGA

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

vol.E106-A, no.1, pp.23-34, 2023-01-01

被引用文献数

3

---

This paper presents a convex-analytic framework to learn sparse graphs from data. While our problem formulation is inspired by an extension of the graphical lasso using the so-called combinatorial graph Laplacian framework, a key difference is the use of a nonconvex alternative to the l1 norm to attain graphs with better interpretability. Specifically, we use the weakly-convex minimax concave penalty (the difference between the l1 norm and the Huber function) which is known to yield sparse solutions with lower estimation bias than l1 for regression problems. In our framework, the graph Laplacian is replaced in the optimization by a linear transform of the vector corresponding to its upper triangular part. Via a reformulation relying on Moreau's decomposition, we show that overall convexity is guaranteed by introducing a quadratic function to our cost function. The problem can be solved efficiently by the primal-dual splitting method, of which the admissible conditions for provable convergence are presented. Numerical examples show that the proposed method significantly outperforms the existing graph learning methods with reasonable computation time.

著者

Baud Haryo Prananto Iskandar Adit Kurniawan

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Communications Express (ISSN:21870136)

巻号頁・発行日

vol.12, no.1, pp.19-23, 2023-01-01 (Released:2023-01-01)

参考文献数

4

---

Handover is very crucial in cellular communication since it may interrupt data transmission. The traditional handover algorithm works well in ideal conditions, but it may fail in certain conditions such as coverage holes. In this letter, we present our simulation to improve handover performance using machine learning. We implement and perform novel modifications on Near-RT RIC, a new network element by O-RAN, to solve the target cell decision problem using a machine learning algorithm in a network with a coverage hole. We show that this solution is proven superior to the traditional handover algorithm.

著者

Ouyang JUNJIE Naoto YANAI Tatsuya TAKEMURA Masayuki OKADA Shingo OKAMURA Jason PAUL CRUZ

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (ISSN:09168508)

巻号頁・発行日

pp.2022CIP0024, (Released:2023-01-11)

被引用文献数

1

---

The BGPsec protocol, which is an extension of the border gateway protocol (BGP) for Internet routing known as BGPsec, uses digital signatures to guarantee the validity of routing information. However, the use of digital signatures in routing information on BGPsec causes a lack of memory in BGP routers, creating a gaping security hole in today's Internet. This problem hinders the practical realization and implementation of BGPsec. In this paper, we present APVAS (AS path validation based on aggregate signatures), a new protocol that reduces the memory consumption of routers running BGPsec when validating paths in routing information. APVAS relies on a novel aggregate signature scheme that compresses individually generated signatures into a single signature. Furthermore, we implement a prototype of APVAS on BIRD Internet Routing Daemon and demonstrate its efficiency on actual BGP connections. Our results show that the routing tables of the routers running BGPsec with APVAS have 20% lower memory consumption than those running the conventional BGPsec. We also confirm the effectiveness of APVAS in the real world by using 800,000 routes, which are equivalent to the full route information on a global scale.

著者

Gui-Ying Liu Wei-Jun Chen Min Zhao

出版者

The Institute of Electronics, Information and Communication Engineers

雑誌

IEICE Electronics Express (ISSN:13492543)

巻号頁・発行日

vol.20, no.1, pp.20220473, 2023-01-10 (Released:2023-01-10)

参考文献数

30

---

Based on an auxiliary differential equation (ADE) and new weighted Laguerre polynomials (WLPs), an efficient 3-D finite-difference time-domain method (FDTD) with factorized-splitting (FS) scheme is proposed to calculate wave propagation in general dispersive materials. The ADE technique is introduced to model general dispersive materials. Using a new temporal basis, the new WLPs can improve computational efficiency and save computing resources. The FS scheme is used to efficiently solve the huge sparse matrix equation. A numerical example is given to verify the accuracy and the efficiency of the proposed method. The results show its superiority compared with existing methods.