Kyushu University Academic Staff Educational and Research Activities Database
List of Presentations
Arakawa Yutaka Last modified date:2021.05.18

Professor / Advanced Information and Communication Technology / Department of Advanced Information Technology / Faculty of Information Science and Electrical Engineering

1. Masato Uchino, Billy Dawton, Yuki Hori, Shigemi Ishida, Shigeaki Tagashira, Yutaka Arakawa, Akira Fukuda, Initial Design of Two-Stage Acoustic Vehicle Detection System for High Traffic Roads, The 2nd International Workshop on Pervasive Computing for Vehicular Systems, 2020.03.
2. Yusuke Soneda, Yuki Matsuda, Yutaka Arakawa, Keiichi Yasumoto, Multimodal recording system for collecting facial and postural data in a group meeting, 27th International Conference on Computers in Education, ICCE 2019, 2019.11, By the spread of active learning and group work, the ability to collaborate and discuss among the participants becomes more important than before. Although several studies have reported on that micro facial expressions and body movements give psychological effects to others during conversation, most of them are lacking in quantitative evaluation and there are few datasets about group discussion. In this research, we proposed a highly reproducible system that helps to make datasets of group discussions with multiple devices such as an omnidirectional camera (360-degree camera), an eye tracker and a motion sensor. Our system operates those devices in one-stop to realizing synchronized recording. To confirm the feasibility, we built the proposed system with an omnidirectional camera, 4 eye trackers, and 4 motion sensors. Finally, we succeeded to make a dataset by recording 8 times group meeting by using our developed system easily..
3. Yuito Sugata, Yutaka Arakawa, Keiichi Yasumoto, Battery-less Place Recognition System using Multiple Energy Harvesting Elements, 18th IEEE Sensors, SENSORS 2019, 2019.10, We propose a room-level place recognition system which uses energy harvesting elements as both sensor and power source. As energy harvesting elements, we focus on solar cells. In our previous work, by combining multiple types of cells and learning the difference of the generated power, we succeeded to distinguish ten places thanks to different characteristics of solar cells according to their materials. However, since the previous research focused on investigating the feasibility of our fundamental idea, it used a microcomputer board that requires an additional battery to measure the amount of generated power. Hence, it did not reach the level to utilize the energy harvesting elements as a power supply required for running the whole system. In this paper, we re-design our previously proposed mechanism to measure the amount of generated power of the energy harvesting elements and propose the novel mechanism to measure the amount of generated power by using the generated power without any additional battery. In stead of measuring the amount of generated power, our system has the circuit that counts how many times the electrolytic capacitor has been fully charged. The capacitor used is the minimum size required for reading the time stamp and write it to the memory. Finally, we can measure the amount of generated power by counting the time stamps recorded per unit of time. We designed and implemented the new circuit on PCB, and applied our system to room-level place recognition. As a result, we confirmed that our system can accurately distinguish the eight places..
4. Yusuke Soneda, Yuki Matsuda, Yutaka Arakawa, Keiichi Yasumoto, M3B Corpus
Multi-modal meeting behavior corpus for group meeting assessment, 2019 ACM International Joint Conference on Pervasive and Ubiquitous Computing and 2019 ACM International Symposium on Wearable Computers, UbiComp/ISWC 2019, 2019.09, This paper is the first trial to create a corpus on human-to-human multi-modal communication among multiple persons in group discussions. Our corpus includes not only video conversations but also the head movement and eye gaze. In addition, it includes detailed labels about the behaviors appeared in the discussion. Since we focused on the micro-behavior, we classified the general behavior into more detailed behaviors based on those meaning. For example, we have four types of smile: response, agree, interesting, sympathy. Because it takes much effort to create such corpus having multiple sensor data and detailed labels, it seems that no one has created it. In this work, we first attempted to create a corpus called “M3B Corpus (Multi-Modal Meeting Behavior Corpus),” which includes 320 minutes discussion among 21 Japanese students in total by developing the recording system that can handle multiple sensors and 360-degree camera simultaneously and synchronously. In this paper, we introduce our developed recording system and report the detail of M3B Corpus..
5. Haruka Wada, Zhihua Zhang, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, Quickcarerecord
Efficient care recording application with location-based automatic view transition and information complement, 13th International Symposium on Medical Information and Communication Technology, ISMICT 2019, 2019.05, In Japan, the demand for nursing home is increasing due to the increase in the number of elderly people. However, the work burden for nursing staffs is very large. Specially, they spend much time in making care reports which reduces the time for doing the essential care for residents in a nursing home. Therefore, to reduce the load for staffs, the system on which staffs can create reports easily and instantly is needed. In this paper, we propose a mobile memo system that switches the view according to the location automatically and assists inputting the necessary information. Our proposed system enables care staffs to prepare the care report about caring for the elderly person quickly. Through the evaluation in the emulated environment, we show that our system succeed to reduce the time for recording by 37.9% and 58.9%, compared with the conventional system and traditional handwriting, respectively..
6. Atsushi Otsubo, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, BeatSync
Walking Pace Control Through Beat Synchronization between Music and Walking, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 2019.03, Walking has been attracting attention as an important means for prevention and improvement of lifestyle diseases such as high blood pressure and diabetes. In contrast of its importance, not many people know the appropriate pace or amount of walking for themselves. In our previous research, we proposed a system to recommend a route with appropriate walking speed/pace for consuming target calories while keeping load within a moderate range by predicting heart rate variation if walking along the road. However, no system is available which enables a user to naturally adjust his/her walking speed to the specified one while walking. In this paper, focusing on the entertainment effect of the music, we propose a smartphone application called BeatSync which leads everyone to walk naturally and accurately toward the target walking speed..
7. Kenta Taki, Yuki Matsuda, Yutaka Arakawa, Keiichi Yasumoto, Design and Implementation of Notification Information Survey System and Survey Results Toward Use-Side Adaptive Notification Management, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 2019.03, Many interrupt notification methods have been studied, but most of the existing research assumes that, except for the target application, the applications do not control the notification timing. However, if other applications are controlled by the same notification timing, interrupt timing will become concentrated and the effects of notification timing control may not be exerted. In addition, since the installed applications are different for each user, it is necessary to control notification timings while taking into consideration the behaviors of all the applications installed on a user's smartphone. In this research, we define notification timing control while considering the behaviors of all installed applications as 'Adaptive Notification Management' and then conduct diversity surveys of notifications received by users. In this paper, we report on a system that acquires all notification information while excluding privacy data. We also report on experimental results using actual data collected using crowdsourcing and discuss how to realize the application realizing adaptive notification management..
8. Zhihua Zhang, Yutaka Arakawa, Harri Oinas-Kukkonen, Design of Behavior Change Environment with Interactive Signage Having Active Talk Function, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 2019.03, In this paper, we construct an interactive signage system, which is able to actively talk to users who are passing the signage system and at the same time tries to induce behavioral changes through visual and auditory stimulation. On top of our previous feasibility study, we re-design our proposed system based on the persuasive system design (PSD) model and the behavior change support system (BCSS) theory. The new design consists of 4 parts: recognizing (identifying and classifying users), executing (sending triggers and inducing behavior change), reviewing (recording users' reaction), and feedback (keeping or improving users' motivation). To track users' status and performance, we use the smartphone and the smartwatch to collect users' bio-data (e.g. heart rate, number of steps) and users' location. To send user triggers continuously without being interrupted by notifications from other applications, we set the interactive signage in the daily action line of users and present information to users when they pass the signage. In order to make the system more persuasive, we pick up eight features from the 28-feature list of PSD and apply them to our design..
9. Naoki Yoneoka, Yutaka Arakawa, Keiichi Yasumoto, Detecting Surrounding Users by Reverberation Analysis with a Smart Speaker and Microphone Array, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 2019.03, Recently, smart speakers like Amazon Echo and Google Home have been spread widely. Those devices support users' life through voice interface by receiving voice commands to operate appliances and order goods to online shops. Meanwhile, it is reported that smart speakers are vulnerable to some malicious attacks which steal personal information and/or order unnecessary goods by uttering voice from a device nearby the speaker, abusing the fact that the smart speakers cannot distinguish human voice from machine voice. A new type of attack called DolphinAttack which utters ultrasonic voice inaudible to human is also reported. Therefore, a method to identify which of human or machine is sending voice commands to a smart speaker is desired. In this paper, to prevent such machine-voice based attacks to a smart speaker in absence of residents, we propose a system consisting of a speaker and a microphone array to detect the existence of a human nearby, supposing it can be incorporated in a smart speaker in the future. In our proposed system, the speaker emits sonar sound generated based on Orthogonal Frequency Division Multiplexing (OFDM) in all directions, the microphone array with 8 channels attached on top of the speaker receives the reflected sound, and the human existence is judged by comparing the reflected sound with that measured in the same environment without human. Through experiments with a prototype system, we confirmed that our proposed system can detect the human existence by measuring the reflected signal of 0.5 second..
10. Yoshinori Umetsu, Yugo Nakamura, Yutaka Arakawa, Manato Fujimoto, Hirohiko Suwa, EHAAS
Energy harvesters as a sensor for place recognition on wearables, 2019 IEEE International Conference on Pervasive Computing and Communications, PerCom 2019, 2019.03, A wearable based long-term lifelogging system is desirable for the purpose of reviewing and improving users lifestyle habits. Energy harvesting (EH) is a promising means for realizing sustainable lifelogging. However, present EH technologies suffer from instability of the generated electricity caused by changes of environment, e.g., the output of a solar cell varies based on its material, light intensity, and light wavelength. In this paper, we leverage this instability of EH technologies for other purposes, in addition to its use as an energy source. Specifically, we propose to determine the variation of generated electricity as a sensor for recognizing "places" where the user visits, which is important information in the lifelogging system. First, we investigate the amount of generated electricity of selected energy harvesting elements in various environments. Second, we design a system called EHAAS (Energy Harvesters As A Sensor) where energy harvesting elements are used as a sensor. With EHAAS, we propose a place recognition method based on machine-learning and implement a prototype wearable system. Our prototype evaluation confirms that EHAAS achieves a place recognition accuracy of 88.5% F-value for nine different indoor and outdoor places. This result is better than the results of existing sensors (3-axis accelerometer and brightness). We also clarify that only two types of solar cells are required for recognizing a place with 86.2% accuracy..
11. Wataru Sasaki, Masashi Fujiwara, Manato Fujimoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, Predicting Occurrence Time of Daily Living Activities Through Time Series Analysis of Smart Home Data, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 2019.03, Recently, various smart home services such as smart air-conditioning, monitoring of elderly/kids and energy-efficient appliance operations are emerging, thanks to technologies of indoor positioning of users and recognition of Activity of Daily Living (ADL). Meanwhile, to realize more convenient home services, it will become more important to be able to predict occurrence time of each ADL. ADL prediction is a challenging problem since it is difficult to train a prediction model by general machine learning algorithms which use only the data at a moment for classification. In this paper, taking into account temporal dependency of data (consumed power of appliances and position of users) collected during daily life, we propose a method for constructing models to predict ADL with LSTM (Long Short-Term Memory). In the proposed method, we construct LSTM-based models by setting occurrence time of each activity to an objective variable. First, we tried to construct a multi-class classification model which outputs one of several predefined time ranges (time elapsed from present) as the occurrence time of the activity. Through preliminary experiment, we found that this model results in low accuracy in predicting the occurrence time. Then, as the second approach, we constructed a before-or-after classification model which judges if the activity occurs within a specified time or not. We applied this model to our smart home data and confirmed that it achieves better prediction accuracy for all activities..
12. Masashi Takata, Yugo Nakamura, Yohei Torigoe, Manato Fujimoto, Yutaka Arakawa, Keiichi Yasumoto, Strikes-Thrusts Activity Recognition Using Wrist Sensor Towards Pervasive Kendo Support System, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 2019.03, In this paper, we focus on Kendo, which is a traditional sport in Japan, and propose a strikes-thrusts activity recognition method using a wrist sensor towards a pervasive Kendo support system. We collected the inertial sensor data set from 6 subjects. We attached 3 inertial sensor units (IMUs) on the subjects body, and 2 IMUs on the Shinai (bamboo sword used for Kendo). On the body, IMUs were placed on the Right Wrist, Waist and Right Ankle. On the Shinai, they were placed on the Tsuba and Saki-Gawa. We first classified strikes-thrusts activities consisting of 4 general types, Men, Tsuki, Do, and Kote, followed by further classification into 8 detailed types. We achieved 90.0% of F-measure in the case of 4-type classification and 82.6% of F-measure in the case of 8-type classification when learning and testing the same subjects data for only Right Wrist. Further, when adding data of sensors attached to the Waist and Right Ankle, we achieved 97.5% of F-measure for 4-type classification and 91.4% of F-measure for 8-type classification. As a result of leave-one-person-out cross-validation from 6 subjects to confirm generalized performance, in the case of 4-type classification, we achieved 77.5% of F-measure by using only 2 IMUs (Right Wrist and Shinai Tsuba)..
13. Dmitrii Fedotov, Yuki Matsuda, Yuta Takahashi, Yutaka Arakawa, Keiichi Yasumoto, Wolfgang Minker, Towards Real-Time Contextual Touristic Emotion and Satisfaction Estimation with Wearable Devices, 2019 IEEE International Conference on Pervasive Computing and Communications Workshops, PerCom Workshops 2019, 2019.03, Following the technical progress and growing touristic market, demand on guidance systems is constantly increasing. Current systems are not personalized, they usually provide only a general information on sightseeing spot and do not concern about the tourist's perception of it. To design more adjustable and context-aware system, we focus on collecting and estimating emotions and satisfaction level, those tourists experience during the sightseeing tour. We reducing changes in their behaviour by collecting two types of information: conscious (short videos with impressions) and unconscious (behavioural pattern recorded with wearable devices) continuously during the whole tour. We have conducted experiments and collected initial data to build the prototype system. For each sight of the tour, participants provided an emotion and satisfaction labels. We use them to train unimodal neural network based models, fuse them together and get the final prediction for each recording. As tourist himself is the only source of labels for such system, we introduce an approach of post-experimental label correction, based on paired comparison. Such system built together allows us to use different modalities or their combination to perform real-time tourist emotion recognition and satisfaction estimation in-the-wild, bringing touristic guidance systems to the new level..
14. Yuta Kido, Teruhiro Mizumoto, Hirohiko Suwa, Yutaka Arakawa, Keiichi Yasumoto, A Cooking Support System for Seasoning with Smart Cruet, 5th International Conference on Human Aspects of IT for the Aged Population, ITAP 2019, held as part of the 21st International Conference on Human-Computer Interaction, HCI International 2019, 2019.01, In recent years, the number of people who use online recipe services in order to cook has increased. It is difficult to match food taste to user’s preference because an online recipe page shows a recipe to realize just one taste even though there are countless numbers of recipes in an online recipe service. Our preliminary experiment using convenience food to investigate the user’s preference showed that the preference of almost participants differed from the taste of food cooked following the recipe printed in the package. It has also been reported that 76.5% of housewives are interested in cooking activities. However, using measuring spoon is difficult to use in order to determine the exact amount of seasonings. When we conducted a preliminary experiment to confirm the error between the input amount based on a rough estimation and the specific amount, the average error for small spoon was 46.2%, and the average error for large spoon was 31.8% even though the participants cook frequently. Especially, for an elderly person requiring low salt or low sugar, if the error becomes too big than appropriate amount, leading to endangering his life or losing the pleasures of eating. However, since there is no device currently in use that can assist in putting seasonings, a device other than measuring spoon is needed to determine the amount of seasoning for cooking. In this research, we aim to bring the taste of food with an online recipe close to the user’s preferable taste without burdening the user. In this paper, we propose a cooking support system which analyzes user’s preference from user’s feedback according to the five grade evaluation for each meal, adjusts the amount of seasoning for a recipe depending on user’s preference, and supports to add the seasoning by Smart Cruet equipped with motion sensors, LED light, and BLE communication interface. We conducted an experiment for 14 days to confirm how many days are needed to bring the adjustment of the seasonings close to the preferable taste for the user. We were able to reach the desired adjustment in 7 days. Furthermore, we found Smart Cruet could measure the adding amount of seasoning with 5.56% average error..
15. Yuki Matsuda, Dmitrii Fedotov, Yuta Takahashi, Yutaka Arakawa, Keiichi Yasumoto, Wolfgang Minker, Estimating user satisfaction impact in cities using physical reaction sensing and multimodal dialogue system, 9th International Workshop on Spoken Dialogue System Technology, IWSDS 2018, 2019.01, Following the increase in use of smart devices, various real-time environmental information becomes available everywhere. To provide more context-aware information, we also need to know emotion and a satisfaction level in a viewpoint of users. In this paper, we define it as “a user satisfaction impact (USI)” and propose a method to estimate USI by combining dialogue features and physical reaction features. As dialogue features, facial expression and acoustic feature are extracted from multimodal dialogue system on a smartphone. As physical reactions, head motion, eye motion, and heartbeat are collected by wearable devices. We conducted the preliminary experiments in the real-world to confirm the feasibility of this study in the tourism domain. Among various features, we confirmed that eye motion correlates with satisfaction level up to 0.36..
16. Yoshitaka Ueyama, Morihiko Tamai, Yutaka Arakawa, Keiichi Yasumoto, Gamification-based incentive mechanism for participatory sensing, 2014 IEEE International Conference on Pervasive Computing and Communication Workshops, PERCOM WORKSHOPS 2014, 2014.01, Since participatory sensing relies on users' active participation, several monetary incentive mechanisms for attracting users' participation have been proposed. However, to make users participate in 'heavy' sensing tasks (either physically or mentally), stronger incentive is required. Thus, the total amount of rewards paid by the client will quickly rise. In this paper, we propose a novel incentive mechanism based on gamification for participatory sensing to reduce the total amount of rewards paid by the client. The proposed incentive mechanism incorporates a status level scheme depending on earned reward points like airline's mileage services, so that users with higher status can earn more reward points. We also introduce a ranking scheme among users and a badge scheme based on gamification so that users are attracted by getting not only monetary reward points but also sense of accomplishment. We formulate the problem of sensing given PoI (points of interest) with minimal reward points and devise a heuristic algorithm for deriving the set of users to which requests are sent and appropriate reward points for each request. The algorithm requires the participation probability distribution for each tuple of a user, reward points, and the burden of a sensing task. To obtain the probability distribution, we implemented a prototype of a participatory sensing system with the proposed incentive mechanism and conducted an experiment with 18 users for 30 days. As a result, we confirmed that the gamification mechanism increased participation probability from 53% (without gamification) to 73%..
17. Yutaka Arakawa, Yuki Sonoda, Koki Tomoshige, Shigeaki Tagashira, Akira Fukuda, Implementation of WiFi/Bluetooth-based Smart Narrow Field Communication, 2014 7th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2014, 2014.01, In this poster, we introduce our developed wireless tag system called Smart Narrow Field Communication (SNFC). The purpose of SNFC is to provide a long url of the contents on the Internet easily like QR code and NFC (Near Field Communication). SNFC assumes a device name of wireless applications as a tag for recognizing a target content. The relationship between a device name and the url is managed on our cloud system. In addition to a device name, our system takes other user contexts such as gender and age into consideration for deciding the target content. The advantage of SNFC is that all the common devices such as WiFi router or Bluetooth mouse can be used as a tag..
18. Yuko Hirabe, Yutaka Arakawa, Keiichi Yasumoto, Logging all the touch operations on Android, 2014 7th International Conference on Mobile Computing and Ubiquitous Networking, ICMU 2014, 2014.01, Touch operation has already become a common technique, and will be adopted to most electrical appliances in the future. Therefore, we suppose that a user's touch operation will be one of important contexts for realizing the future context-aware system. Through observation of the user's touch operation, a system could estimate the user's emotion, skill, etc. In this demonstration, we exhibit our system for logging all the touch operations on Android. In addition to the logging, our system can analyze and visualize several popular touch operations..
19. Yutaka Arakawa, Yuki Sonoda, Shigeaki Tagashira, Akira Fukuda, WiFiTag
Direct link from the real world to online digital contents, 2012 7th International Conference on P2P, Parallel, Grid, Cloud and Internet Computing, 3PGCIC 2012, 2012.12, WiFiTag is a simple and low cost solution for associating the real world to the online media such as web sites and YouTube. Our idea is to redirect a user's access based on the information of surrounding WiFi access points. Compared with WiFi-based indoor positioning system, our system requires no calculation and no much access points. This is because our system associates the digital content not with the location but with the AP itself. as the information of AP, we use ESSID, BSSID, and RSSI. by uploading a scanned WiFi information to the WiFiTag server, a terminal can get the proper URL as a response. Relationship between the WiFiTag and the URL have been defined ahead. WiFiTag realize "real to virtual" connection easily. for example, by associating lab's SSID to lab's HP, a visitor can access a lab's HP easily and directly, when the visitor comes to our lab. a camera required for QR code don't need for our system. in addition, a special card reader and touch action required for NFC are also unnecessary. If WiFi has already exist, no additional cost is necessary for our system. in this paper, we describe a overall concept of WiFiTag and show the availability and feasibility of our proposed system through some experimental evaluation results..
20. B-15-7 Basic Behavior of Network Switching on Android OS for realizing a Context-Aware Network Selection.
21. ICT to Vitalize Japan : 10. Information and Communication Technology for Love.
22. Routing Protocol for Deadline-Aware Data Aggregation Method in Energy-Efficient Wireless Sensor Networks.
23. Improvement in packet import method of Hadoop-based Packet Analyzer for High Volume Packet Data.
24. A common key generation technique based on similarity of received signal strength for secure wireless face-to-face communication
A spread of short-range and infrastructure-less wireless communication devices increases opportunities for temporarily exchanging information in a face-to-face style, called wireless face-to-face communication. In such wireless communication, a critical issue with secure information exchange is encryption key sharing without the aid of any centralized administration. In this paper, we propose a novel key sharing technique for wireless face-to-face communications. The main idea is to generate the same encryption key on a communication pair using received signal strength indicators (RSSI) from observable wireless LAN appliances, rather than distribute a prepared key between the pair. The generation for the same key is realized by utilizing the similarity of RSSI observed within a small area. Furthermore, we examine the successful ratio for generating the same key and consider the security level for the proposed method..
25. Symbolic device for short-range wireless pairwise communication
Laptop computers and cellular phones often have the capability for short-range wireless communication such as adhoc mode in wireless LAN and Bluetooth. However, the use of the capability is limited due to the lack of consideration for short- range communications in conventional communication protocols; i.e., an unnatural and troublesome procedure is required to specify targets especially within a nearby area. In this paper, we propose a symbolic device to support short-range wireless communications that provides the ability to specify a target on the real-world environment. More specifically, a short-range communication device is logically concerned with its corresponding symbolic device and the short-range communication with a target is established by linking the symbol device with the target directly or indirectly. Furthermore, we designed and implemented a prototype system for the proposed device using wired and wireless LAN..
26. Traffic Reduction Using Data Aggregation for Positioning System on Wireless Mesh Network.
27. Generation Technique of Secret Information for Handheld Devices Exploiting Characteristics of Multipath Fading Channel.
28. Satoru Okamoto, Sho Shimizu, Yutaka Arakawa, Naoaki Yamanaka, Experiment of the In-band Message Communication Channel for GMPLS controlled Ethernet, 2008 34th European Conference on Optical Communication, ECOC 2008, 2008.12, In-band Message Communication Channel, which can transport IP packets, for GMPLS protocols is implemented. The prototype system with Mac-in-Mac Ethernet transport mechanism and GMPLS Ethernet control is successfully demonstrated..
29. Shimizu Sho, Kihara Taku, Yutaka Arakawa, Yamanaka Naoaki, Shiba Kosuke, Hardware based scalable path computation engine for multilayer traffic engineering in GMPLS networks, 2008 34th European Conference on Optical Communication, ECOC 2008, 2008.12, A parallel data-flow hardware based path computation engine that makes multilayer traffic engineering more scalable is proposed. The engine achieves 100 times faster than conventional path computation scheme..
30. Daisuke Ishii, Takahito Fujii, Yutaka Arakawa, Iwao Sasase, Fair Burst Dropping Technique for Optical Composite Burst Switched Multi-Hop Network, 2003 IEEE Pacific Rim Conference on Communications Computers and Signal Processing (PACRIM 2003), 2003.11, Optical Composite Burst Switching(OCBS) that can improve the performance of the packet loss probability without Fiber Delay Lines(FDLs), has the problem that it is unfair about the number of hops to the destination edge router for the packet loss probability. In this paper, in order to achieve the fair packet loss probability regardless of the number of hops to the destination edge router, we propose the burst dropping technique that configures the threshold for determining whether the head-dropping(HD) technique is applied or not The HD technique is the burst dropping technique which reduces packet loss due to burst contention in OCBS. We compare the packet loss probability and throughput performance of our proposed scheme with those of the conventional one by computer simulations. As a result, we show that our proposed scheme can achieve the fair packet loss probability regardless of the number of hops to the destination edge router compared with a conventional one..
31. Yutaka Arakawa, Makoto Sakuta, Iwao Sasase, QoS Scheme with Burst Dropping in Optical Burst Switching, 2003 IEEE Pacific Rim Conference on Communications Computers and Signal Processing (PACRIM 2003), 2003.11, We propose a new QoS control scheme by using burst dropping in optical burst switched network. Our proposed scheme consists of Burst Dropping (BD) technique at core nodes and packet arrangement technique at edge nodes. BD technique has been proposed as the effective solution that can improve packet loss at intermediate nodes. By using BD technique, the head of the latter arriving burst are dropped at a burst contention. Our proposed scheme mixes packets of different priorities into a single burst, and arranges them in ascending order of priority at burst assembly. At contention, lower priority packets that are located in former part of a burst are often discarded and higher ones are not often discarded. By computer simulations, we evaluate the QoS performance in terms of packet loss probability and the end-to-end delay performance. As a result, we show that our proposed scheme can provide a basic QoS in terms of packet loss without causing a degradation of end-to-end delay of higher priority packets..
32. Yutaka Arakawa, Y. Akiyama, K. Sakamoto, Y. Nishino, I. Sasase, Port selected packet discarding scheme in ATM networks, 2001 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing (PACRIM 2001), 2001.01, Early Packet Discard (EPD), one of the congestion control schemes at ATM switch in IP over ATM networks, enables us to use efficiently the link bandwidth and buffer space. However there is a problem that buffer overflow occurs, when many links are connected to the ATM switch and packets arrive at the ATM switch from most of them. In this paper, we propose a new packet discarding scheme in which the number of ports accepted at the same time is taken into account. In the proposed scheme, by using two thresholds, packets are discarded according to the number of ports accepted at the same time. By computer simulations, we evaluate a badput and a throughput of the proposed scheme and compare them with those of the conventional scheme. As a result, we show our proposed scheme can improve badput performance without causing the degradation of the throughput..