27655175
A Convex-Hull Based Algorithm to Connect the Maximal Independent Set in Unit-Disk Graphs
In this paper we propose and analyze a localized convex-hull based algorithm to connect a maximal independent set. The cardinality of the resultant connected dominating set is at most 76 · opt +19, where opt is the size of a minimum connected dominating set. To our knowledge, this is a dramatic improvement compared to the best published results in the same context [1,6] . Our algorithm plays an important rule in efficiently constructing a virtual backbone for ad hoc and sensor networks.
285048
Location-centric storage for safety warning based on roadway sensor networks
We propose a novel vision for roadway safety warning based on sensor networks, aiming at providing user-friendly zero-delay safety warnings to motorists. Our idea leverages the advanced sensing, networking and storage technologies. Roadway sensors detect events and store event records at multiple designated locations along the against traffic direction, such that the passing-by drivers can be alerted to potential dangers or traffic delays through the wireless communication between roadway sensors and the vehicle. We design a location-centric storage (LCS) protocol, which manages the propagation and storage of event records based on the time needed to clear the road. In LCS, the density of the sensors storing an event record decreases logarithmically with respect to the distance to the event location. Thus, the closer to the event position, the more number of warnings a driver may obtain. LCS is further tailored for the case of ''highway'' sensor networks when all sensors are deployed along a straight line mimicking a highway, and the more complex case when two roads intersect at some place. We conduct both theoretic analysis and simulation study to verify the performance of LCS when applied to roadway sensor networks for safety warning. The results indicate that LCS is fair to all sensors. We conclude that roadway safety warning based on sensor networks is a promising idea for realizing ITS's ''Zero Fatality, Zero Delay'' roadway safety philosophy.
17825087
Feature Matrix Models for Information Extraction
To extract useful information which really contribute to the target issue from huge amounts of data or text description is an important task towards a number of research fields (e.g., genomics study and text mining). In this paper, a general feature matrix model (FMM) is proposed aiming to provide partial answer to this task. Specifically, one instantiation of FMM is used for identifying feature genes based on microarray data, and the other for extracting information according to case description.
11279692
TPSS: A Time-Based Positioning Scheme for Sensor Networks with Short Range Beacons
Location discovery is a challenging problem in sensor networks. However, many sensor network applications require the availability of the physical sensor positions. In this paper, we present TPSS, a time-based positioning scheme for sensor networks when a number of short-range beacons are randomly and uniformly deployed. By measuring the Time Difference of Arrivals (TDoAs) of signals from nearby beacons, nodes can use TPSS to effectively estimate their locations based on the range differences through trilateration. TPSS requires no long-range beacons to cover the entire network, an essential difference compared to TPS [2] and iTPS [15]. Features of TPSS include high scalability, low communication and computation overheads, no requirement for time synchronization, etc. Simulation results indicate that TPSS is an effective and efficient self-positioning scheme for sensor networks with short range beacons.
35870958
A New Data Mining Method Using Organizational Coevolutionary Mechanism
Organizational coevolutionary algorithm for classification (OCEC), is designed with the intrinsic properties of data mining in mind. OCEC makes groups of examples evolved, and then rules are extracted from these groups of examples at the end of evolution. OCEC is first compared with G-NET and JoinGA. All results show that OCEC achieves a higher predictive accuracy. Then, the scalability of OCEC is studied. The results show that the classification time of OCEC increases linearly.
7227804
Personalized web search by mapping user queries to categories
Current web search engines are built to serve all users, independent of the needs of any individual user. Personalization of web search is to carry out retrieval for each user incorporating his/her interests. We propose a novel technique to map a user query to a set of categories, which represent the user's search intention. This set of categories can serve as a context to disambiguate the words in the user's query. A user profile and a general profile are learned from the user's search history and a category hierarchy respectively. These two profiles are combined to map a user query into a set of categories. Several learning and combining algorithms are evaluated and found to be effective. Among the algorithms to learn a user profile, we choose the Rocchio-based method for its simplicity, efficiency and its ability to be adaptive. Experimental results indicate that our technique to personalize web search is both effective and efficient.
43661392
Web Service for Communication Service Management
2900457
Database selection in intranet mediators for natural language queries
12401745
On splitting public keys for the public key infrastructure
Certificates and the public key infrastructure (PKI) play an vital role in electronic commerce. The framework of splitting the public key in the PKI is presented in this paper. Aimed to enhance the security level from both the perspectives of certificate issuing and certificate revocation, the framework splits the public key into multiple parts, and generates a certificate for each part. The framework is designed to be flexible to allow various levels of security depending on the requirements, while minimising changes to the existing e-commerce system and PKI. The key-split system maintains CA independence and allows for either smaller certificates or the size of key to be increased.