An Experimental Approach to Examine a Multi-Channel Multi-Hop Wireless Backbone Network

This paper presents an experimental deployment of a multi-channel multi-hop wireless backbone network (WBN) with an OpenFlow-based traffic management method. Specifically, a set of APs, each of which uses a single but different channel, is connected by Ethernet and thus constructs a Virtual AP (VAP), thereby achieving a WBN with multi-ple channels. To exibly control traffic ows transmitted over a multi-channel multi-hop WBN, we propose a simple traffic management method based on the OpenFlow control. In the performance evaluation, we rst conduct a preliminary experiment as a lab scale　and then deploy a 6-hop WBN enabling to provide the Internet access service in a conference (from proof-of-concept to a practical environment). Since the control messages are inherently transmitted with the introduction of OpenFlow, the way of isolation be-tween control plane and data plane will become a critical issue to actually deploy the proposed system for the Internet service. We additionally employ a wireless control network for the conference experiment. The experimental results show that the proposed　WBN can increase the network capacity in accordance with the number of channels, thereby providing significant throughput performance for various applications

Data Delivery Method Based on Neighbor Nodes’ Information in a Mobile Ad Hoc Network

This paper proposes a data delivery method based on neighbor nodes’ information to achieve reliable communication in a mobile ad hoc network (MANET). In a MANET, it is difficult to deliver data reliably due to instabilities in network topology and wireless network condition which result from node movement. To overcome such unstable communication, opportunistic routing and network coding schemes have lately attracted considerable attention. Although an existing method that employs such schemes, MAC-independent opportunistic routing and encoding (MORE), Chachulski et al. (2007), improves the efficiency of data delivery in an unstable wireless mesh network, it does not address node movement. To efficiently deliver data in a MANET, the method proposed in this paper thus first employs the same opportunistic routing and network coding used in MORE and also uses the location information and transmission probabilities of neighbor nodes to adapt to changeable network topology and wireless network condition. The simulation experiments showed that the proposed method can achieve efficient data delivery with low network load when the movement speed is relatively slow

Galileo Probe Battery System

The conclusions of the Galileo probe battery system are: the battery performance met mission requirements with margin; extensive ground-based and flight tests of batteries prior to probe separation from orbiter provided good prediction of actual entry performance at Jupiter; and the Li-SO2 battery was an important choice for the probe's main power

Elastic Channel Utilization Against External Radio Interference on SDN-Enabled Multi-Radio Wireless Backhaul Networks

This paper tries to avoid a radio interference while effectively utilizing the resource of interfered channel on SDN-based wireless backhaul networks (WBNs). The densification of small cells on wireless networks is required to handle a lot of traffic for the cloud-based ICT services but inevitably needs a WBN to provide network connectivity at every cell. Since most traffic is delayed or dropped once a WBN suffers from a radio interference coming from outside of the WBN, it is general to avoid using the interfered channel or switch a route spatially. Although such countermeasures are effective to avoid an external radio interference, it could be less effective in terms of resource utilization because the interfered channel may still remain resource. From this perspective, we propose a method that estimates the residual resource of interfered channel and uses it as much as possible while avoiding the effect arising from the radio interference. Specifically, our proposed method uses the information about incoming/outgoing traffic to estimate the residual resource and migrate a part of traffic to another channel until the amount of incoming traffic and that of outgoing packets are balanced (i.e., the channel is not a bottleneck anymore). The experimental results showed that our method is able to estimate the residual resource of interfered channel and effectively use it even under external radio interference.7th IEEE International Conference on Cloud Networking (CloudNet 2018), 22-24 October, 2018, Tokyo, Japa

Does the tube-compensation function of two modern mechanical ventilators provide effective work of breathing relief?

OBJECTIVE: An endotracheal tube (ETT) imposes work of breathing on mechanically ventilated patients. Using a bellows-in-a-box model lung, we compared the tube compensation (TC) performances of the Nellcor Puritan-Bennett 840 ventilator and of the Dräger Evita 4 ventilator. MEASUREMENTS AND RESULTS: Each ventilator was connected to the model lung. The respiratory rate of the model lung was set at 10 breaths/min with 1 s inspiratory time. Inspiratory flows were 30 or 60 l/min. A full-length 8 mm bore ETT was inserted between the ventilator circuit and the model lung. The TC was set at 0%, 10%, 50%, and 100% for both ventilators. Pressure was monitored at the airway, the trachea, and the pleura, and the data were recorded on a computer for later analysis of the delay time, of the inspiratory trigger pressure, and of the pressure–time product (PTP). The delay time was calculated as the time between the start of inspiration and minimum airway pressure, and the inspiratory trigger pressure was defined as the most negative pressure level. The same measurements were performed under pressure support ventilation of 4 and 8 cmH(2)O. The PTP increased according to the magnitude of inspiratory flow. Even with 100% TC, neither ventilator could completely compensate for the PTP imposed by the ETT. At 0% TC the PTP tended to be less with the Nellcor Puritan-Bennett 840 ventilator, while at 100% TC the PTP tended to be less with the Dräger Evita 4 ventilator. A small amount of pressure support can be equally effective to reduce the inspiratory effort compared with the TC. CONCLUSION: Although both ventilators provided effective TC, even when set to 100% TC they could not entirely compensate for a ventilator and ETT-imposed work of breathing. The effect of TC is less than that of pressure support ventilation. Physicians should be aware of this when using TC in weaning trials

Experimental Study of a Novel Method of Cardiopulmonary Resuscitation Using a Combination of Percutaneous Cardiopulmonary Support and Liposome-encapsulated Hemoglobin (TRM645)

Percutaneous cardiopulmonary support (PCPS) has been applied for cardiopulmonary arrest (CPA). We have developed a novel method of cardiopulmonary resuscitation using PCPS combined with liposome-encapsulated hemoglobin (TRM645) to improve oxygen delivery to vital organs. Ventricular fibrillation was electrically induced to an adult goat for 10 min. Next, PCPS (30 ml/kg/min, V/Q: 1) was performed for 20 min. Then, external defibrillation was attempted and observed for 120 min. The TRM group (n5) was filled with 300 mL of TRM645 for the PCPS circuit. The control group (n5) was filled with the same volume of saline. The delivery of oxygen (DO2) and oxygen consumption (VO2) decreased markedly by PCPS after CPA, compared to the preoperative values. DO2 was kept at a constant level during PCPS in both groups, but VO2 slowly decreased at 5, 10, and 15 min of PCPS in the control groups, demonstrating that systemic oxygen metabolism decreased with time. In contrast, the decreases in VO2 were small in the TRM group at 5, 10, and 15 min of PCPS, demonstrating that TRM645 continuously maintained systemic oxygen consumption even at a low flow rate. AST and LDH in the TRM group were lower than the control. There were significant differences at 120 min after the restoration of spontaneous circulation (p&#60;0.05).</p

Loose Matching Approach Considering the Time Constraint for Spatio-Temporal Content Discovery

Cross-domain data fusion is becoming a key driver in the growth of numerous and diverse applications in the IoT era. We have proposed the concept of a new information platform, the Geo-Centric Information Platform (GCIP), that enables IoT data fusion based on geolocation. The GCIP dynamically produces spatio-temporal content (STC) by combining cross-domain data in each geographic area and then provides the STC to users. In this environment, it is difficult to find some particular STC requested by a user because the user cannot determine which STC is created in each area beforehand. Although, in order to address this difficulty, we proposed a content discovery method for GCIP in the previous study, the temporal property of STC was not taken into account, despite the fact that the available (effective) period of each of STC is limited. In the present paper, we propose a new loose matching approach considering the time constraint for STC discovery. Simulation results showed that the proposed method successfully discovered appropriate STC in response to a user request.13th International Conference on Intelligent Networking and Collaborative Systems (INCoS-2021), September 1-3, 2021, Asia University, Virtual Conference (Online Presentation

SDN-based in-network early QoE prediction for stable route selection on multi-path network

As QoE is useful to uniformly handle many kinds of application flows, we have been tackling QoE-oriented network resource management based on SDN technology. Toward this goal, our previous study proposed a QoE measurement method for on-going streaming flows. However, the standard QoE calculation model requires at least 8 s for collecting the flow information. In this study, we tackle early QoE prediction on a SDN-enabled multi-path network. To predict video QoE as soon as possible, we exploit not only packet loss rate measured regularly but also the number of packet transmissions by short-period measurement at the flow arrival. Finally, through experiments, we demonstrated that QoE of all flows can be maximized by selecting an appropriate route based on the predicted QoE.12th International Workshop on Information Network Design (WIND-2020), in conjunction with 12th International Conference on Intelligent Networking and Collaborative Systems (INCoS-2020), August 31st - September 2nd, 2020, University of Victoria, Canada（新型コロナ感染拡大に伴い、現地開催中止