[in Japanese]

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Wireless communications in industrial environments are seriously affected by reliability and performance issues, due to the multipath nature of obstacles within such environments. In order to utilize wireless systems for M2M applications in industrial environments, it is necessary to investigate and model their channel characteristics for optimal design and reliability assessment. However, the wireless channel characterization in such environments has not been sufficiently addressed in the literature within the scope of our knowledge. In this paper, to shed light on the channel modeling for plant applications, we measure and analyze the indoor channel characteristics in a typical thermal power plant. Our results indicate that the channel characterization of the plant environment is specific when compared with the general environments such as home and office. The findings in this paper provide a useful guidance to the design of wireless system for the realization of reliable control systems in power plants.

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This paper proposes an adaptive arbitration interframe space number (AIFSN) control for ZigBee and wireless LAN (WLAN) coexistence. The authors have been proposed the coexistence method which is utilizing the AIFS specified in the IEEE802.11e standard greater than the distributed interframe space (DIFS). Because the AIFS value is always high in the conventional method, the ZigBee success ratio is improved but the WLAN throughput is degraded. To overcome this problem, the AIFS is changed adaptively according to the reception of ZigBee Data frames. The adaptive AIFSN control is applied to the conventional method. Compared with the conventional method, simulation results show the degradation of ZigBee success ratio is small and the WLAN throughput is improved.

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This paper clarifies the practical performance of cooperative communication systems with multiple base stations on realistic environment with imperfect channel state information (CSI). Achievable spectral efficiencies are evaluated to compare the previously proposed inter-cell interference (ICI) cancellation scheme with fractional frequency reuse (FFR) as well as the cooperative multiuser multiple-input multiple-output (MU-MIMO). The proposed method realizes quasi-decentralized cooperation and can significantly reduce preprocessing complexity on large-scale base station cooperation. In the system level simulations, two CSI imperfections are considered: estimation error and restrictions on available number of CSI. The results revealed that the proposed method can achieve higher spectral efficiency than cooperative MU-MIMO, 3.5% on average value and 112% higher at the CDF=5%, even in imperfect CSI conditions.

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A Mobile Ad hoc Network (MANET) has been studied as a means to autonomously construct a distributed wireless multi-hop network, which facilitates network deployment especially in developing countries. This paper tackles the improvement of efficiency in routing algorithms over a MANET by making use of location data. Our approach uses location-aided two-hop neighbor information to reduce the number of overhead packets and to enable void handling in a geographic network. Most previous researches based on location routing protocols suffer from unnecessary overhead packets, long end-to-end delays and low packet reachability. To solve these problems, we propose Location-aided Route Discovery Based on Two-hop Neighbor Information (LARTNI) and its extension for void handling (LARTNI+VH). Simulation studies have proven the effectiveness of LARTNI and LARTNI+VH.

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Recently, various equipment has wireless devices such as smart phone, personal computer, television and so on. These equipment are connecting to the other equipment using wireless LAN or Bluetooth. Wireless LAN and Bluetooth frequency band is able to make free use of ISM (Industry-Science-Medical) band by keep the radio law of each country. However, data errors occur due to the other wireless equipment. Therefore, the equipment needs the lowering method for interference to the other wireless equipment. In this paper, we proposed a new simulation of evaluation for the lowering interference method. And we show the example of execution for the proposed method.

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In this paper, we study a design method for minimizing the cost of placement of wireless base stations used for radio based train control systems. First, we present the problem that is to determine the number of wireless base stations and their placement locations under several constrained conditions relevant to stability railroad transportation. Second, we formulate this problem, and to solve this problem, we propose a heuristic algorithm. Finally, we verify the effectiveness of our algorithm through computational experiments.

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In the field of traditional oriental medicine, two types of treatment style, which are an acupuncture treatment and a moxibustion treatment have been performed. These treatments are used and effected by doctor or acupuncturist in their clinic or hospital and widely spread. However such a general treatment, it is not deeply discussed about mechanism of heat transfer modality and about temperature distribution in the treatment of moxibustion. Also, it is not discussed about temperature distribution of deep human tissue during acupuncture treatment. It comes from the difficulty of noninvasive measurement of internal human body with small change of electromagnetic wave signals noninvasively. In this study, a temperature distribution for acupuncture and moxibustion treatment is measured and analyzed using thermography and MRI by measuring the phase of longitudinal relaxation time of protons. The experimental results of measured temperature distribution under the human legs have been demonstrated. The result of temperature analysis in the human body is also reported.

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Domestic power situation is changing rapidly, and effective energy-saving measures in offices and homes are required. In office buildings, lighting consumes about 20% of the power consumption, and air-conditioner consumes about 45% of the power consumption. Therefore, energy-saving measures for these equipment are important. In this paper, we propose an energy-saving method for lighting and air-conditioner in office building considering person's location in the floor. The proposed method detects persons in the floor, and controls lighting equipment and air-conditioning equipment to appropriate illuminance and temperature around the persons. Thus, the proposed method increases the energy-saving effect by narrowing the controlled zone to make the room temperature and illuminance appropriately, and maintain comfort for the persons. In this study, we evaluate the energy-saving effect of lighting and air-conditioner by simulation and experiments in the real office building.

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Pedestrian detection is an important area in computer vision and plays a key role in intelligent vehicles. The objective of this paper is to provide a method to select the discriminative visual word based on the bag-of-features algorithm for pedestrian detection from near-infrared images. It calculates the difference in the total appearance frequency for each visual word of pedestrian and non-pedestrian images. The visual words which exhibit greater absolute values are considered as more efficient for pedestrian detection and can be selected. The experiment results showed that the proposed method keeps nearly the same detection accuracy even if only 40% of the visual word is selected. In addition, we investigated the distribution of discriminative feature points which belong to the selected visual words from near-infrared images and visible spectrum images.

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This paper proposes a method for an automatic classification system of surface mount devices (SMDs) focused on the periodicity of leads. Automatic classification methods for the type of SMD are required as preprocessing for mounting SMDs in chip mounters. Due to the variations of connector parts, the previous method has a low accuracy rate. This paper presents a classification method for multiple types of SMDs by using Higher-order Local AutoCorrelation (HLAC) features from the power spectrum of an SMD image. Support Vector Machine (SVM) automatically classifies connector parts including the periodicity of leads by using HLAC features from a spectrum. The experimental results show that the proposed method improved the accuracy rate of the connectors (115 samples) from 40.0[%] to 91.3[%]. For all kinds of parts (748 samples), the accuracy rate was improved from 89.2[%] to 96.0[%].

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In this paper, we propose a new framework that employs whole-word hidden Markov models with a relaxed algorithm for likelihood calculation. Although voice activity detection (VAD) is an essential technique in order to provide a sophisticated voice interface, a perfect VAD has not been proposed yet. An incomplete VAD leads to misdetections frequently. Since the conventional likelihood calculation, which has limitation in edge states, assumes that VAD works well, we cannot obtain sufficient recognition accuracy against the misdetections. The proposed method is a technique to improve the performance against misdetected speech in the framework which uses whole-word HMMs. The method employs an algorithm which relaxes the limitation of likelihood calculation in the edge states. In order to verify the effectiveness of the proposed method, we carried out recognition experiments for artificially shortened segments. With the conventional method, the average recognition rates were 91.81%, 91.50%, 89.56%, and 85.13% under 3, 4, 5, and 6 states/phoneme conditions, respectively. However, the proposed method allowed us to achieve 91.88%, 92.64%, 92.74%, and 93.14% under the same conditions. Furthermore, we confirmed the effectiveness of the proposed method through experiments combined with CENSREC-1-C.

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A large facility such as plants and buildings have many and various sensors so that “training data less” and “parameter tuning free” are required for anomaly detection. Discord method that finds the nearest neighbor subsequence with high speed is a state of the art satisfying the above needs. However, the selection of window size for discord is a remaining issue. We notice that discord behavior in transient state is different from that in steady state and show that the optimal window size depends on the anomaly shape because of a discord-shift in transient state (In a transient state, the nearest neighbor subsequence of an anomaly subsequence shifts from the normal subsequence corresponding to the anomaly subsequence originally.). We also define an evaluation index to compare the detection accuracy for anomalies with different window sizes and specify the condition when a discord-shift occurs in a transient state. Lastly, we consider a window size tuning method on the basis of the above knowledge.

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To use more effective media contents, creation of media contents suited to each user's feelings is important objective in the area of engineering. We have already proposed an Interactive Genetic Algorithm (IGA) accepting user's manipulation on gene of solution candidates as additional evaluation, while most of conventional Interactive Evolutionary Computations (IECs) accepted only user's scoring or selection. This study aims to apply the IGA accepting user's manipulation to creation of music melodies. To investigate the efficiencies of the application of the IGA for creation of music melodies, listening experiments were conducted. In the experiments, the subjects listened to music melodies created from the IEC system based on the proposed method. With the system, the subjects could manipulate key of music note in music melodies. The experimental results showed that significant increase in fitness value. Furthermore, the melody created by the users themselves was the best among four experimental conditions.

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Nowadays, dietary habits of younger person is diversified and there are many person that have not good habits. This problem will cause many diseases, therefore, it is important to fix their dietary habits. In this study, we describes the method to detect groups of university students that have similar dietary habits of using the school cafeteria. This knowledge of groups will be utilized when manager of cafeteria plans some events or fairs to invite good dietary habits to students. In this study, we obtained purchase data at the school cafeteria and we analysed them. The data were collected from meal prepaid card that records the history of the purchased food. 520 males and 305 females from Kanazawa University served as subjects. Identification number, gender, date of use, dish name, nutrition information is recorded as ID-POS data. By focusing on “combination of cuisine” of the user, we revealed the dietary pattern. First, “a combination of cuisine” are classified into twelve clusters by using the clustering method. This processing defines as a cuisine clustering. Next, users who are close to the choice of cuisine cluster are classified into eight clusters. In this way, we proposed the method of high prediction accuracy user clustering by performing two phases clustering. To understand each cluster, we checked the nutrition information for each cluster and suggested a method of the eating habits for mainly insufficient nutrition support.

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Optimization benchmark problems are useful because many researchers utilize them in order to fairly evaluate the performance of optimization methods. Most of them, however, are relatively simple, and optimization methods which can solve such problems cannot necessarily solve practical and complicated problems. In order to enable researchers to evaluate the performance of the optimization methods for the practical and complicated problems, this paper proposes an operational planning and scheduling benchmark problem in an automatic picking system based on a real system. In addition, we propose a method of generating a solution which is theoretically guaranteed to be feasible and superior for the benchmark problem. In the benchmark problem, products are sorted by loading them onto lanes and by discharging them onto a conveyor. Because the benchmark problem includes an assignment problem of the products to the lanes and a scheduling problem of the products on the conveyor, it is complicated.

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In late years, personal information must be protected at the agency in the field of insurance. We develop an agency contract system that protects personal information of the contractor and information to confirm intention to contract by background texture watermarks. When the contractor carries an application form, it may be folded, rumpled or waved little. In this case, contractor's information must be recognized from background watermarks printed on the application form. But it cannot be recognized surely folded, rumpled or waved application form by the conventional method. In this paper, we propose a new recognition of watermark dot information from folded, rumpled or waved application form. The new recognition is composed of crooked point sequence recognition expressing character borders by searching around calculated point, and dot recognition by shading folded, rumpled or waved paper and emphasizing dot in luminosity from this paper. As a result, we got correct recognition ratio of more than 99% from folded, rumpled or waved paper.

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Smart meter is expanding rapidly in Japan, too. IEEE802.15.4 series, 3G/LTE and ITU-T G.9903 is used mainly as communication method for it. HD-PLC is proposed in this paper as wired high speed communication method because these main methods do not include wired high-speed technique.  Some communication tests using HD-PLC was done at the same test site as G.9903. This test site is simulated a 20-story residential building. HD-PLC showed high performances at the test site.

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A command input interfaces based on lip motion features can be used with or without vocalization. In a previous study, it was revealed that the fluctuations of lip movement attributable to vocalization, and the difference of the command recognition accuracy of both utterance conditions. However, the change in lip motion due to utterance experience is not clear yet.  In this paper, we investigate the fluctuation of lip motion due to utterance experience for 7 participants among 10 days. The results of our investigation showed that the cumulative sum of the inter-frame difference of the lip motion features and utterance experience have negative correlation, and variation in lip motion due to utterance experience having differences among individuals.

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