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Papers - Sasase, Iwao

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Energy-efficient standby mode algorithms in short-range one-to-one millimeter-wave communications

Ryoko Matsuo, Tomoya Tandai, Tomoko Adachi, Hideo Kasami and Iwao Sasase

IEICE Transactions on Communications E97-B （ 11 ） 2469 - 2479 2014.11

Research paper (scientific journal), Joint Work, Accepted

This paper proposes two energy-efficient standby mode algorithms in short-range one-to-one 60 GHz millimeter-wave (mmWave) communications. Among the many usage scenarios for mmWave radio, file downloading from kiosk terminals or peer-to-peer sync service with portable terminals are of great interest. The proposed two energy efficient standby mode algorithms for one-to-one communications get assured connection setup time and take each terminal’s different requirement for reduction of its power consumption into consideration. This experimental result is the same as the analysis result and it is verified that our proposed standby algorithm works as designed.

Adaptive usage of polarization andpPhysical carrier sensing in wireless ad hoc networks

Sann Maw Maung and Iwao Sasase

The 20th Asia and Pacific Conference on Communications 2014.10

Research paper (international conference proceedings), Joint Work, Accepted

In this paper, optimal physical carrier sensing range is calculated based on the signal to interference and noise ratio and distance between transmitter and receiver nodes in the ad hoc network to avoid the packet collision in ongoing receiver node. After that, the adaptive usage of polarized antenna will be applied to further increase the aggregate throughput in ad hoc network. The simulation results show that the proposed methods can give the higher aggregate throughput for ad hoc network.

Opportunistic routing protocol with grid-based relay slot selection in energy harvesting WSNs

Ryota Negishi, Kentaroh Toyoda and Iwao Sasase

The 20th Asia and Pacific Conference on Communications, 2014.10

Research paper (international conference proceedings), Joint Work, Accepted

In this paper, we propose a lightweight grid-based relay slot selection scheme in EH-WSNs. In our scheme, we use square-shaped grid and divide the network virtually to give each node primitive coordination and each intermediate node decides its relaying slot by calculating the differential of grid-index between a sender and a receiver. Based on grid-based coordination, our scheme turns multiplications into lightweight subtractions and this reduces the computational complexity and required memory. In addition, we also propose a probabilistic relaying scheme to reduce collisions in each relaying slot. We evaluate the conventional and proposed schemes through the computer simulation and show that our scheme reduces the computational complexity and achieves comparable throughput to the conventional scheme

Singular value decomposition based adaptive transmission scheme for misalignment cross polarized MIMO system

Sann Maw Maung and Iwao Sasase

The 20th Asia and Pacific Conference on Communications 2014.10

Research paper (international conference proceedings), Accepted

Reduced Complexity on Mobile Sensor Deployment and Coverage Hole Healing by Using Adaptive Threshold Distance in Hybrid Wireless Sensor Networks,

Aye Mon Htun, Maung Sann Maw and Iwao Sasase

The 2014 IEEE 25th International Symposium on Personal, Indoor and Mobile Radio Communications - Mobile and Wireless Networks (IEEE PIMRC 2014 - Mobile and Wireless Networks) 2014.09

Research paper (international conference proceedings), Accepted

In this paper, we propose a method that reduces the complexity on the relocation of initial deployment and coverage hole healing of mobile sensor nodes in the hybrid Wireless Sensor Networks (WSNs). Our method finds the best-ordered ways of mobile nodes’movement to give the shortest distance movements for mobile nodes in WSN. Adaptive threshold distance is used to eliminate the consideration of some mobile nodes, which are already occupied or situated within the threshold distance from optimal new positions. The simulation results show that the proposed methods can give much smaller calculation time to find the shortest paths for the movements of mobile nodes in WSN.

Priority based routing for forest fire monitoring in wireless sensor network

Takuma Koga, Kentaroh Toyoda and Iwao Sasase

The Journal of Telecommunications and Information Technology (JTIT) 2014 （ 3 ） 90 - 97 2014.09

Research paper (scientific journal), Joint Work, Accepted

Recently, forest fire monitoring system in wireless sensor networks has received much attention. The conventional scheme receives fire alert data quickly to inform fire forest event to the sink. However, since two or more nodes may detect a fire, high priority fire detection data frequently collide. In this paper, we propose a new forest fire monitoring system in order to reduce dropped rate of high priority fire detection data, by specifying a high priority received data only immediately after fire detection and just before the destruction by fire. Furthermore, the node only transmits high priority data to a node which has a low possibility of destruction by fire for low end-to-end delay of high priority fire detection data. The simulation results show that our proposed scheme can reduce dropped rate of high priority data and the end-to-end delay, and have less effect of wind compared with the conventional scheme.

Low False Alarm Rate RPL Network Monitoring System by Considering Timing Inconstancy between the Rank Measurements

Takumi Matsunaga, Kentaroh Toyoda and Iwao Sasase

The Eleventh International Symposium on Wireless Communication Systems (ISWCS'2014), 2014.08

Research paper (international conference proceedings), Joint Work, Accepted

Deterministic Blocker Tag Detection Scheme by Comparing Expected and Observed Slot Status in UHF RFID Inventory Management Systems

Ryo Hattori and Kentaroh Toyoda and Iwao Sasase

Workshops of the 16th IEEE International Conference on High Performance Computing and Communications (HPCC2014), 2014.08

Research paper (international conference proceedings), Joint Work, Accepted

In this paper, we propose a deterministic BT detection by letting tags respond in the specified slots and comparing the expected and observed status of each slot. Response slot is determined by using hash function, a random number, frame length and tags ID. This way enables the reader to predict the status of each slot. Our scheme immediately detects BT if the expected status is different from the observed status. Our scheme can also detect even though BT jams low-rate. Simulation results show that our scheme performs better than the conventional BT detection scheme in terms of the number of required slots to detect BT.

Concurrent Moving-based Connection Restoration Scheme between Actors to Ensure the Continuous Connectivity in WSANs

Yuya Tamura, Takuma Koga, Shinichiro hara, Kentaroh Toyoda and Iwao Sasase

Workshops of the 16th IEEE International Conference on High Performance Computing and Communications (HPCC2014 2014.08

Research paper (international conference proceedings), Joint Work, Accepted

In this paper, we propose a concurrent moving-based connection restoration scheme between actors to ensure the continuous connectivity. By sending a message to neighbor actor before moving, an actor can inform when it starts to move and where it moves to. Thus, neighbor actors which receive a message can calculate when it starts to move for concurrent move of actors. An actor starts to move when the communication with neighbor actors is unavailable due to neighbor actor’s move. Further, when the actor starts to move, it creates sub-paths to its moving neighbor actor for continuous connectivity. The network restoration time is shortened because of concurrently moving instead of moving one by one. We show that our scheme restores the network connectivity much robuster and faster than the conventional scheme by computer simulation.

Priority Based Routing for Forest Fire Monitoring in Wireless Sensor Network

Takuma Koga, Shinichiro Hara, Kentaroh Toyoda and Iwao Sasase

IEICE Information and Communication Technology Forum 2014 (ICTF 2014) 2014.05

Research paper (international conference proceedings), Accepted

We propose a new forest fire monitoring system in order to reduce dropped rate of high priority fire detection data, by specifying a high priority on data only immediately after fire detection and just before the destruction by fire. Furthermore, the node only transmits high priority data to a node which has a low possibility of destruction by fire for low end-to-end delay of high priority fire detection data. The simulation results show that our proposed scheme can reduce dropped rate of high priority data and the end-to-end delay compared with the conventional scheme.

FFS認証においてチャレンジ分割により検証に必要な乗算回数を提言させる手法の検討

SASASE IWAO

情報処理学会論文誌 55 （ 5 ） 1518 - 1529 2014.05

Research paper (scientific journal), Joint Work, Accepted

検証に伴う演算量を制御できるようにチャレンジを分割することによって攻撃の影響を低減する方式を提案する．さらに，検証に伴う演算は対応するチャレンジの要素が1 である場合に1024 ビット長の乗算剰余演算が発生することが主な原因であるため，チャレンジの生成時にチャレンジの要素が1 としてよい数に上限値を設けることにより演算量を低減させる．チャレンジを複数に分割した際の計算時間およびメモリ量について評価を行い，本方式の有効性を示す.

SPIT callers detection with unsupervised random forests classifie

Kentaroh Toyoda and Iwao Sasase

2013 IEEE International Conference on Communications - Communication and Information Systems Security Symposium (ICC13 CISS) （IEEE) 2013.06

Research paper (conference, symposium, etc.), Joint Work, Accepted

Asynchronous receiver-initiated MAC protocol exploiting stair-like sleep in wireless sensor networks

Takahiro Wada, I-Te Lin and Iwao Sasase

IEICE Trans. on Communications E96-B （ 1 ） 119-126 2013.01

Research paper (scientific journal), Joint Work, Accepted

Cooperative MAC protocol with distributed relay selection using group-based probabilistic contention

I-Te Lin, Mio Sekiya and Iwao Sasase

18th Asia-Pacific Conference on Communications (APCC'12), 2012.10

Research paper (scientific journal), Joint Work, Accepted

Power saving localization by considering node's distance and localization error for reducing redundant packets in mobile WSNs

Shinji Kano, Tatsuya Koizumi and Iwao Sasase

2012 IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'12) （IEEE) 2012.09

Research paper (scientific journal), Joint Work, Accepted

Power saving localization by considering node's distance and localization error for reducing redundant packets in mobile WSNs

Shinji Kano, Tatsuya Koizumi and Iwao Sasase

2012 IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC'12) （IEEE) 2012.09

Research paper (scientific journal), Joint Work, Accepted

Load-balanced cluster-based WSNs by separating relay function from cluster heads

Shinichiro Hara, Tatsuya Kiozumi and Iwao Sasase

Triangle Symposium on Advanced ICT 2012 (TriSAI2012) 2012.09

Research paper (scientific journal), Joint Work, Accepted

Grid-based ｒouting ｐrotocol with cell division and rotation in wireless sensor networks

Hidetoshi Kajikawa1, I-Te Lin and Iwao Sasase

IEICE Communications Express (ComEX) 1 （ 3 ） 95-100 2012.08

Research paper (scientific journal), Joint Work, Accepted

Primary traffic based cooperative multihop relaying with preliminary farthest relay selection in cognitive radio ad hoc networks

I-Te Lin and Iwao Sasase

IEICE Transactions on Communications E95-B （ 8 ） 2586-2599 2012.08

Research paper (scientific journal), Joint Work, Accepted

Gateway discovery algorithm based on multiple QoS path parameters between mobile node and gateway node

Safdar H.Bouk and Iwao Sasase

Journal of Communications and Networks, KICS 14 （ 4 ） 434-442 2012.08

Research paper (scientific journal), Joint Work, Accepted

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