Noise Amplification in Human Tumor Suppression following Gamma Irradiation

The influence of noise on oscillatory motion is a subject of permanent interest, both for fundamental and practical reasons. Cells respond properly to external stimuli by using noisy systems. We have clarified the effect of intrinsic noise on the dynamics in the human cancer cells following gamma irradiation. It is shown that the large amplification and increasing mutual information with delay are due to coherence resonance. Furthermore, frequency domain analysis is used to study the mechanisms

INEMO: Distributed RF-Based Indoor Location Determination with Confidence Indicator

Using radio signal strength (RSS) in sensor networks localization is an attractive method since it is a cost-efficient method to provide range indication. In this paper, we present a two-tier distributed approach for RF-based indoor location determination. Our approach, namely, INEMO, provides positioning accuracy of room granularity and office cube granularity. A target can first give a room granularity request and the background anchor nodes cooperate to accomplish the positioning process. Anchors in the same room can give cube granularity if the target requires further accuracy. Fixed anchor nodes keep monitoring status of nearby anchors and local reference matching is used to support room separation. Furthermore, we utilize the RSS difference to infer the positioning confidence. The simulation results demonstrate the efficiency of the proposed RF-based indoor location determination

On multi-copy forwarding protocols for large data chunk dissemination in vehicular sensor networks

Abstract Moving vehicles have been sensing all kinds of data on the road in which multimedia data possesses a large portion. These data is often forwarded to vehicles in a region of interest or the monitoring center in an opportunistic manner. With respect to the large volume content, the storage space of relay vehicles is becoming the bottleneck of achieving higher performance, e.g., a data chunk may be rejected or dropped due to insufficient storage of intermediate vehicles. Thus, previous work that only focuses on the delivery metric without considering the data size is not likely to work efficiently in the proposed scenario. As deploying stationary infrastructures is of very large cost and not feasible everywhere, in this paper, we focus on the inter-vehicle data forwarding problem with storage and communication capacity constraints. First, we considered the situation when the vehicles are distributed sparsely. The multi-copy routing challenge is modeled as a multiple knapsack problem. Then, it is extended to a dense scenario. An optimization to the broadcast data forwarding is investigated. With the real data trace, the experiments show that our scheme achieves better performance than the competitors in terms of delay and delivery ratio. A better balance between duplication and performance is also achieved by the multi-copy algorithm

Fuzzy Logic Based Feedback Scheduler for Embedded Control Systems

Abstract. The case where multiple control tasks share one embedded CPU is considered. For various reasons, both execution times of these tasks and CPU workload are uncertain and imprecise. To attack this issue, a fuzzy logic based feedback scheduling approach is suggested. The sampling periods of control tasks are periodically adjusted with respect to uncertain resource availability. A simple period rescaling algorithm is employed, and the available CPU resource is dynamically allocated in an intelligent fashion. Thanks to the inherent capacity of fuzzy logic to formalize control algorithms that can tolerate imprecision and uncertainty, the proposed approach provides runtime flexibility to quality of control (QoC) management. Preliminary simulations highlight the benefits of the fuzzy logic based feedback scheduler.

Noninteractive Localization of Wireless Camera Sensors with Mobile Beacon

Recent advances in the application field increasingly demand the use of wireless camera sensor networks (WCSNs), for which localization is a crucial task to enable various location-based services. Most of the existing localization approaches for WCSNs are essentially interactive, i.e., require the interaction among the nodes throughout the localization process. As a result, they are costly to realize in practice, vulnerable to sniffer attacks, inefficient in energy consumption and computation. In this paper, we propose LISTEN, a noninteractive localization approach. Using LISTEN, every camera sensor node only needs to silently listen to the beacon signals from a mobile beacon node and capture a few images until determining its own location. We design the movement trajectory of the mobile beacon node, which guarantees to locate all the nodes successfully. We have implemented LISTEN and evaluated it through extensive experiments. Both the analytical and experimental results demonstrate that it is accurate, cost-efficient, and especially suitable for WCSNs that consist of low-end camera sensors