Wireless sensor network (WSN) is attracting intensive interests in many application areas. In some scenarios such as monitoring of the coal-mining area or remote area, nodes seldom move and may switch from sleeping to...
详细信息
Wireless sensor network (WSN) is attracting intensive interests in many application areas. In some scenarios such as monitoring of the coal-mining area or remote area, nodes seldom move and may switch from sleeping to waking mode to minimize power consumption. Energy conservation design for the network lifetime extension is the primary issue. By adopting sleep scheduling to keep low duty cycle can help reduce the energy consumption. Random sleep scheduling is a desirable mechanism for its simplicity and guaranteed stable low duty cycle. Moreover, the low duty cycle sleeping of nodes may destroy the connectivity of network. Most of existing WSN routing techniques are designed for fully connected networks assuming that the nodes of the routing path between source and destination are all available at the same time. Maintaining fully connected backbone involves high duty cycle and costly clock synchronization which consumes more energy. If certain delay is tolerant, partially connected routing can achieve successful packet forwarding in networks with the deficiency of connectivity. In this paper a new partially connected routing and simple random sleep scheduling scheme is proposed for WSN with low duty cycle. A continuous time Markov chains (CTMC) connectivity availability model is introduced to evaluate the end to end packet delivery ratio of multi-hop networks subjected to the impact of both frequent disconnection and random sleep latency. The proposed connectivity availability model can also be used as the key metric for route path selection to achieve stable and high performance. Deployment guidelines are given for WSN with random sleep scheduling policy satisfying reliability, timeliness and duty cycle requirements. By modeling and simulation, we find that as compared to the fully connected routing protocol, the partially connected routing design can achieve much higher packet delivery ratio and lower duty cycle within the tolerant delay. The computation and simul
A recently proposed public key cryptosystem based on Chebyshev polynomials suggests a new approach to data encryption. But the security of the cryptosystem has not been investigated in depth, for lack of an appropriat...
详细信息
Concerning the system of hot topics detection about the emergency events, an overall technical framework is established to implement the system. Description and solution strategy about the key issues in the four compo...
详细信息
ISBN:
(纸本)9781622761234
Concerning the system of hot topics detection about the emergency events, an overall technical framework is established to implement the system. Description and solution strategy about the key issues in the four components of the system are provided. In terms of the content and structure features of the news reports as well as the distribution feature of the report sources, the text clipping method and the modified model of feature weighting calculation are proposed based on the VSM text representation model and the TF-IDF formula. The news reports about the earthquake emergency event are evaluated for this model as the data sources. Experiment results indicate that the information such as the headline, the lead and relevant feature parameters by clipping the main body of the news report can be considered as the sample set of the hot topics to be identified. Furthermore, compared with the classical model, the modified feature items weighting calculation model is more efficient in execution and more adaptive in terms of the text representation capability.
This paper introduces a two-stage Linear Logic based program synthesis approach to automatic RESTful web service composition. The Linear Logic theorem proof is applied at both resource and service invocation method le...
详细信息
A recently proposed public key cryptosystem based on Chebyshev polynomials suggests a new approach to data encryption. The sequence of Chebyshev polynomial is proved to be periodically, but its symmetry properties hav...
详细信息
A recently proposed public key cryptosystem based on Chebyshev polynomials suggests a new approach to data encryption. The sequence of Chebyshev polynomial is proved to be periodically, but its symmetry properties have not been investigated in depth. In this paper, a new representation of Chebyshev polynomial is introduced to study these properties, and their impacts on the cryptosystem. It is shown that the factual private key space of the cryptosystem is only half or quarter of the period of Chebyshev polynomial sequence. Proper parameters should be chosen to ensure the security of the cryptosystem.
This paper introduces a two-stage Linear Logic based program synthesis approach to automatic RESTful web service composition. The Linear Logic theorem proof is applied at both resource and service invocation method le...
详细信息
This paper introduces a two-stage Linear Logic based program synthesis approach to automatic RESTful web service composition. The Linear Logic theorem proof is applied at both resource and service invocation method levels, which greatly improves the searching efficiency and guarantees the correctness and completeness of the service composition. Furthermore, the process calculus is used as formalism for the composition process, which enables the approach to be executable at the business management level. The process calculus is attached to the Linear Logic inference rules in the style of type theory, so the process model is extracted directly from the complete proof. An example is given to show the extraction of a process model from a Linear Logic proof search.
Inferring user preferences from users’ historical feedback is a valuable problem in recommender systems. Conventional approaches often rely on the assumption that user preferences in the feedback data are equivalent ...
详细信息
Inferring user preferences from users’ historical feedback is a valuable problem in recommender systems. Conventional approaches often rely on the assumption that user preferences in the feedback data are equivalent to the real user preferences without additional noise, which simplifies the problem modeling. However, there are various confounders during user-item interactions, such as weather and even the recommendation system itself. Therefore, neglecting the influence of confounders will result in inaccurate user preferences and suboptimal performance of the model. Furthermore, the unobservability of confounders poses a challenge in further addressing the problem. Along these lines, we refine the problem and propose a more rational solution to mitigate the influence of unobserved confounders. Specifically, we consider the influence of unobserved confounders, disentangle them from user preferences in the latent space, and employ causal graphs to model their interdependencies without specific labels. By ingeniously combining local and global causal graphs, we capture the user-specific effects of confounders on user preferences. Finally, we propose our model based on Variational Autoencoders, named Causal Structure Aware Variational Autoencoders (CSA-VAE) and theoretically demonstrate the identifiability of the obtained causal graph. We conducted extensive experiments on one synthetic dataset and nine real-world datasets with different scales, including three unbiased datasets and six normal datasets, where the average performance boost against several state-of-the-art baselines achieves up to 9.55%, demonstrating the superiority of our model. Furthermore, users can control their recommendation list by manipulating the learned causal representations of confounders, generating potentially more diverse recommendation results. Our code is available at Code-link.
暂无评论