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Wireless trace data play an important role in wireless network researches. However, publishing the raw WLAN traces poses potential privacy risks of network users. Therefore, it is necessary to sanitize users' sensitive information before these traces are published, and provide high data utility for wireless network researches as well. Although some existing works based on various anonymization methods have started to address the problem of sanitizing WLAN traces, we find the anonymization techniques cannot provide strong and provable privacy guarantee by analyzing a real WLAN trace dataset. Differential Privacy is the only framework that can provide strong and provable privacy guarantee. However, our analysis shows that existing studies on differential privacy fail to provide effective data utility for query operations on multi-dimensional and large-scale datasets. Aiming at WLAN trace datasets that have unique characteristics of multi-dimensional and large-scale, this paper proposes a privacy-preserving data publishing algorithm which not only satisfies differential privacy but also realizes high data utility for query operations. We prove that the proposed sanitization algorithm satisfies ϵ -differential privacy. Furthermore, the theoretical analysis shows the noise variance in our sanitization algorithm is O (log o (1) n / ϵ 2) which indicates the algorithm can achieve high data utility on large-scale datasets. Moreover, from the results of extensive experiments on an enterprise-scale WLAN trace dataset, we also show that our sanitization algorithm can provide high data utility for query operations. [ABSTRACT FROM AUTHOR]

Industrial wireless sensor clouds (IWSCs) are indispensable in industrial applications and can operate in tough industrial environments by using industrial wireless sensor nodes to perceive and control devices. Because wireless sensor nodes are often deployed in unattended, remote-controlled environments, attackers may impersonate legal nodes to change device parameters. Such unexpected events could lead to disastrous consequences. It is difficult for an intrusion detection system to detect such attacks. Therefore, an authentication scheme becomes one of an effective approaches to ensuring security. However, authentication schemes for industrial wireless sensor clouds have not yet been adequately studied. The current approach is only applicable to an authentication scheme based on the shared secret key of the wireless sensor cloud and cannot be applied to a dynamic multiple-keys authentication scheme. Based on this scheme, this paper studies a game-based dynamic multiple-keys authentication scheme. Based on the probability of interception of the key and the leak probability of devices’s operating authorization, the paper sets up an authentication framework for a dynamic multiple-keys game. It also derives the optimal strategy which game players can use to maximize security utility and analyze the evolution process of the trust in the dynamic multiple-keys game. The experimental results show that this approach can successfully improve the security of IWSC. [ABSTRACT FROM AUTHOR]

With the prosperity of cloud computing, many mobile nodes choose to deliver their certificate by service AP nodes, where each service AP node as a broker is responsible for authenticating virtual resource access with mobile users who are likely to be malicious in the underlying service requests. However, this access control system requires mobile users’ certificate information and may fail due to their privacy. In light of the growing privacy concerns, this paper proposes a certificate-aware framework for online access control system in mobile computing, where users are compensated for their privacy certificate and operation disclosure and are motivated to present more certificate information. In this framework, a broker pays a trust degree to users and virtual authentication coordinators for disclosing more certificate information. This paper models the interactions among virtual authentication coordinators, the authentication broker and mobile users as a three-stage game, where every player aims at maximizing its own utility, and the trust allocation is achieved by G value learning. Numerical results have shown that the proposed certificate-aware framework is effective, as it enables all players to maximize their utilities and improve the degree of the trust of mobile computing systems. [ABSTRACT FROM AUTHOR]

The complexes of B3O3H3 with acetylene and its substituted derivatives C2HX (X=H, F, Cl, Br, CH3, NH2) are explored by theoretical calculations using MP2 and M06-2X methods with aug-cc-pVDZ as the basis set. The different molecular electrostatic potential features of B3O3H3 with benzene (C6H6) and borazine (B3N3H6) result in different stable structures of the complexes with C2HX. The geometric analysis indicates that the global minimum is the parallel stacked (PS) structure with the linear C–C triple bond lies on the top of B3O3H3, and this is much different from that of the B3N3H6...C2HX complex, in which the C–H bond directs towards the B3N3H6 ring (T-shaped). The H-bonded structure where the C–H interacts with the O atom of B3O3H3 is found to be a local minimum. Besides, there is an additional X...O halogen-bonded structures for the B3O3H3...C2HX (X=Cl, Br) complexes. As for the PS geometry, when one H atom in C2H2 is replaced by different X groups, the binding energies of the complexes increases in the order of F

The article discusses a electron bunch excitation method (EBEM) used in simulations to obtain the characteristics of the slow-wave structures that operate at various frequency bands.

A magnetic Bi2Fe4O9/Bi2MoO6 heterojunction was synthesized by a facile one-pot solvothermal method, and the photodegradation performance was evaluated by degrading methylene blue (MB) and tetracycline hydrochloride (TC). Compared with pure Bi2MoO6 composite, the Bi2Fe4O9/Bi2MoO6 heterojunction with 10% Bi2Fe4O9 had much higher catalytic performance, which can degrade MB and TC completely within 150 and 180 min. The characterization results show that a p–n heterojunction formed between Bi2Fe4O9 and Bi2MoO6. Combining with trapping experiments, a direct Z-scheme mechanism was proposed to effectively separate photodegradable electron–hole pairs at the Bi2Fe4O9/Bi2MoO6 heterojunction interface. Moreover, the obtained catalysts can be recovered easily from liquid system via the external magnet field due to the sufficient magnetism. After five recycles, no significant decrease on the degradation efficiency of MB and TC can be found show that BiFeMo-2 has excellent chemical stability in the application of organic pollutants degradation under visible-light irradiation. Thus, the prepared Bi2Fe4O9/Bi2MoO6 catalyst has the advantages of high visible light catalytic activity, excellent chemical stability and magnetic separation, and has broad application prospects in environmental purification. A novel magnetic recoverable Bi2Fe4O9/Bi2MoO6 catalyst was facilely prepared. BiFeMo-2 sample showed a higher activities for MB and TC photodegradation under visible-light irradiation due to formation of a p–n heterojunction with high quality interface between Bi2Fe4O9 (220) and Bi2MoO6 (131), which can improve charge transfer effectively follow the Z-scheme mechanism. [ABSTRACT FROM AUTHOR]