Capturing and analyzing the actual packets in networks is useful in order to understand the behaviors of a system. Tap-as-a-Service (TaaS), an OpenStack project, has been proposed to enable capturing packets in a virtual network. TaaS, by expanding OpenStack Neutron APIs, provides a functionality that allows users to set up mirroring of the production traffic between virtual machines (VMs) and to transfer the mirrored traffic to the monitoring VM. However, the production traffic and the mirrored traffic affect each other because they share the same physical underlay network in the reference TaaS implementation. This may result in interference of resources. Since capturing packets on the virtual network may affect the performance of business applications running on the VMs, it is impossible to analyze the normal condition. In this paper, we propose two methods to solve this issue: (1) isolation of the production traffic and the mirrored traffic at the underlay network and (2) a quality of service (QoS) control method of mirrored traffic. Using these methods, we can reduce the influence of the mirrored traffic on the performance of the production traffic. Moreover, we also discuss the experimental results. The results confirm the effectiveness of the proposed methods.

The most critical problem in high-precision stages for semiconductor and LCD manufacturing is cable disturbance, which can be caused by power cables and communication lines. In our previous study, we designed a novel single-axis high-precision stage using wireless power transfer technology, which avoids cable disturbance. Here, we further develop this concept and propose a multi-axis wireless high-precision. Experimental results demonstrate the effectiveness of the multi-axis wireless high-precision stage.

In the RoboCup Mixed Reality Soccer League, the location and direction of each micro robot on the field are detected by a camera positioned above the field. However, setting and adjusting the camera to achieve greater accuracy takes a very long time. Besides, the detection process is influenced by the surrounding environment, including illuminance of the room and location of the field. Therefore, while the robots are in play, accuracy gradually decreases as the illuminance changes over time and eventually, the robots become invisible to the camera. In these situations, changes in illuminance and motion blur can cause serious issues. To solve this problem, we apply a rotation search method in the detection system, which is a “vision tracking system”. In addition, we implement a redesigned vision tracking system and evaluate the new system. Our results confirm that the new system is effective.

The popular technology for the information recommendation of books or web pages is based on taste information from many users, but it is important to be based on difficulty and proficiency for the recommendation of learning materials. We have developed an algorithm to estimate difficulty of learning materials and proficiency of learners, for recommendation considering difficulty of learning materials. The algorithm uses only a bipartite learner-material graph that consists of the reader relations with materials and learners. In this paper, we describe how to make an accurate data to evaluate the estimated difficulty, and report about the result that evaluated the precision of our proposed algorithm.

In a number of engineering fields, information on the distance to the target is very important. We previously proposed an acoustic distance measurement method based on interference between the transmitted and reflected waves, which can be used for distance measurement over a short range. In the previously proposed method, a sound source of the transmitted wave must be known in advance. In the present paper, we propose a new acoustic distance measurement method based on phase interference obtained using the cross-spectral method with adjacent microphones, which does not require the condition that a sound source of the transmitted wave is known. Finally, we confirmed the validity and effectiveness of the newly proposed method through both computer simulation and evaluation experiment in a real environment.

High-precision stages are used for the fabrication of integrated circuits, liquid crystal displays and so on. Since higher integration density and product quality are continuously required for the development of industry and informatics, not only the stage position but also the stage attitude needs to be controlled rapidly and precisely. The attitude is determined by roll, pitch and yaw motions which are affected by nonlinearity and coupling caused by Euler's equation and rotational kinematics. These effects deteriorate the attitude control performance. This paper proposes a MIMO nonlinear feedforward attitude controller which compensates such effect. The effectiveness of the proposed approach is verified by simulations and experiments.

In the model of perfectly secure message transmission (PSMT) schemes, there are n channels between a sender and a receiver. An infinitely powerful adversary A may corrupt (observe and forge) the messages sent through t out of n channels. The sender wishes to send a secret s to the receiver perfectly privately and perfectly reliably without sharing any key with the receiver. In this paper, we show the first 2-round PSMT for n = 2t + 1 such that not only the transmission rate is O(n) but also the computational costs of the sender and the receiver are both polynomial in n. This means that we solve the open problem raised by Agarwal, Cramer, and de Haan at CRYPTO 2006. The main novelty of our approach is to introduce a notion of pseudobasis to the coding theory. It will be an independent interest for coding theory, too.

This paper proposes a test syntheses method for datapaths. The proposed method goes on design-for-testability while generating control sequences for justification and propagation at register-transfer level. Since the method fully utilizes functions of controllers as well as datapaths, it achieves small area overhead.

A new memory-based architecture for real-time image convolution with variable kernels is proposed. The architecture exploits the highest possible bandwidth inherent in memory and achieves the fine-grain parallelism of computations inside the memory. Unlike existing approaches, the architecture ensures convolution with very large kernels under the real time constraints of video applications. It does not require external memory banks or large I/O count and features single chip VLSI implementation.

This paper describes the implementation of the combined control system incorporating a knowledge based control system and a model predictive multivariable control system in a petroleum plant. The knowledge based control system is used to determine set points for the temperature of the reflux to regulatory controllers using 'if then' type rules based on skilled operators' know-how. The model predictive multivariable control system controls the flow rate of each reflux which is difficult for operators to control because of the large time-delay and interference among those manipulated variables. The implemented combined control system showed a satisfactory performance in controlling the pressure of the actual plant.