Applied Mechanics and Materials Vols. 701-702

Abstract: False lock is a fatal problem in TT&C due to the inevitable excessive delay.It can lead to false carrier acquisition.Based on the knowledge that false lock will not occur in the fast capture bandwidth,a new method for eliminating false lock is proposed.The carrier recovery loop closes only when the uplink carrier signal is detected in fast capture bandwidth by using signal detector and lock detector,then the false lock can be avoid.Compared with traditional methods,this solution is easier to realize and suitable for any type of loop. The experimental results reveal that the proposed method can eliminate false lock effectively.

Abstract: This paper presents both physical and logical methods that are completely one-way transmission without feedback. The imposed hardware isolation is achieved based on the light transmission property with low cost optic components, while the efficiency and accuracy of data transmission is guaranteed by defining new protocol structure based on UDP. Experiments demonstrate that high performance have been achieved after using our proposed protocol mechanism.

Abstract: The real-time prediction of network security situation can significantly improve the monitoring and emergency response capability of the network. However, in practice, if there are a large amount of false predictions, the network administrators should become insensitive and will finally ignore all prediction results. In this paper, we try to solve this issue and propose a novel False Positive Adaptive (FPA) method for network security situation prediction. The main idea of our method is using extra information to reduce the number of false positives in prediction. In the model training step, we take advantage of host and network information to eliminate meaningless alerts produced by security tools such as Intrusion Detection System (IDS) and firewall, thus assuring the accuracy of the training samples. In the prediction step, we utilize the detection information from security tools to confirm the prediction results automatically. If the previous predictions are not detected, they will be considered as false positives and the prediction model will be retrained by incremental learning. In our work, the model training and incremental learning is accomplished efficiently by neural network and boosting algorithm.

Abstract: Attribute-based encryption (ABE) can keep data privacy and realize fine-grained access control. However, the notion of file hierarchy hasn't been presented until now. The problem, the multiple hierarchical files to be shared only using once encryption scheme, cannot be effectively solved. Based on the access structure layered model, a novel access control scheme about file hierarchy is proposed by using ABE to solve the problem. The proposed scheme will not only decrease the number of access structures to one, but also only require a secret key to decrypt all the authorization files. It is proved to be secure against the chosen-plaintext attack (CPA) under the decision bilinear Diffie-Hellman (DBDH) assumption. In addition, the performance analysis results indicate that the proposed scheme is efficient and practical when a large number of hierarchical files are shared.

Abstract: A system includes three power information security defense line is constructed, to achieve the information network, information outside the network, scheduling data network depth protection. According to the information security protection requirements, starting from the overall structure of information systems, taking into account the information system to schedule production system as the core, based on independent research and development of core information security isolation unit, set up three lines of defense in the power of information systems, electricity secondary system, information network systems, information systems outside the network partition protection.

Abstract: Trust is the foundation of all kinds of Internet activity. As a more open resource sharing model, cloud computing environment consists of mass resource owners and users belonged to different control domain. Therefore, the establishment of the trust relationship among the participants and the guarantee of security and efficiency in the computing process are one of the most fundamental problems of cloud computing security. This paper proposes a two-Layer hybrid trust mechanism based on agent trust. In my proposition, trust relationship is relayed and secure computing environment is established among the different participants by the various existing trust methods.

Abstract: Advanced Persistent Threat (APT) is currently reported to be one of the most serious threats. It is very important to detect the APT Trojan as early as possible. There are three types of approaches to conduct APT detection: network traffic analysis, change controlling and sandboxing. Unfortunately, all these approaches have limitations in detecting unknown APT Trojans. This paper proposes a novel APT Trojan detection method by utilizing memory forensics techniques. The proposed method first acquires the raw physical memory image from a target running system and then finds the APT’s traces in the memory image based on the ATP’s characteristics and memory forensics techniques. If enough traces are found, we can judge that there must be Trojans in the target system. Experimental results show that the proposed method can effectively detect new APT Trojans.

Abstract: PoC is an instant communication service based on cellular network, which can transmit information of voice by VoIP. In order to increase the security of network transmission of PoC system, this paper proposes an end-to-end encrypted scheme which implement information synchronization of voice data by using stream encryption.

Abstract: The internet of things (IoT) is developing very speedily. Wireless Sensor Networks (WSNs) are the perception foundation. It is inconvenience to recharge sensor batteries frequently and the sensor power resource is limited in the WSNs. Therefore, one of the most important problems about a WSN is to save energy. To overcome this challenge, a great deal of algorithms was developed in the last few years such as DYCTC. In this paper, we propose RD-LEACH algorithm. Data transmission depends on the residual energy and the distance between the nodes. It can reduce the number of data sent. It solves effectively the energy saving caused by the invalid send and avoids cluster heads concentrate in a small network. Tests show that this algorithm can save approximately 18% of the energy and prolong the network lifetime under the premise of the network connectivity.

Abstract: In the wireless network environment, a large number of applications based on cell phone have emerged. But it has appeared some problems such as large amount of data and limited bandwidth and higher quality transmission in the mobile streaming media data transmission. To solve these problems, this paper designs a bandwidth adaptive streaming media real-time synchronization algorithm. Algorithm firstly analysis the state of the network, and then through real-time increase or decrease the factor method to effectively adjust the code flow rate, thus improve the QoS of streaming in transmission; to meet the learners' online learning, for subsequent teaching and interaction provides a good technical support.