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In recent years, with the large-scale development of infrastructure construction, the concrete mixing station was constantly updated and iterated. At present, there are three common control modes of concrete mixing station: relay control, PLC control and single chip microcomputer control. The mixing station controlled by PLC has reliable performance and high cost performance, which can ensure the quality of concrete and improve the production efficiency of concrete. In this paper, the control process of concrete mixing station is studied. The design content includes the process of the system and the control mode of the mixing station, the design of the overall structure, the selection of hardware and software programming. GX developer and Kingview software are used to control and monitor the process of conveying, weighing, mixing and discharging of concrete mixing station. The design of the concrete mixing plant can realize automatic operation, error alarm, and real-time monitoring and other functions. Experiments show that the system has the characteristics of strong reliability and easy operation, and meets the requirements of the design.

Processors are becoming into multicore ones. The same trend is also emerging in embedded systems. More cores on the single chip provide better concurrent of the tasks. However, the task scheduling becomes the new challenge of embedded operating system. It is still an important issue that how the tasks in multicore embedded system can be scheduled efficiently under the condition of ensuring the real-time constraint. When the number of processor cores increases continuously, such situation also relates to task scheduling for efficiency. In this paper, a novel scheduling algorithm is proposed for multicore embedded systems with the satisfied real-time condition. When the number of on-chip cores increase, this algorithm can meet the new requirements. The experimental results show that our algorithm has achieved its target.

Dynamic searchable encryption enables data owner to store a dynamic collection of encrypted files to the cloud server and generate search tokens of queries over the cloud server. Upon receiving a token, the server can perform the search on the \encrypted data while preserving privacy. Unlike many previous works that focused on a single-user scheme, we present a dynamic searchable encryption scheme with multi-user private search for cloud computing. We consider the use scenario of cloud storage services where an organization outsources its data to the cloud and authorizes a group of users to access the data. Our scheme is dependent on a red-black data structure which is highly parallelizable and dynamic, and its security is proven in the random oracle model.

Public key encryption with keyword search (PKES) enables senders to send encrypted data to a Freceiver like traditional public key encryption (PKE) schemes. The difference between PKES and PKE is that the receiver in PKES can search on the encrypted data which is stored on the third-party server (like a cloud storage server). As far as we know, most of the existed PKES schemes are based on bilinear map, so they are costly in computation and hard to be used in practice. In this paper, we construct a PKES scheme based on factoring, it's computational efficient and secure. The public parameters in our scheme is also short, we just need a public modules and a random element of the set of integers.

Along with variant advantages, the cloud storage gained great attention from both industry and academics since 2007. However, it also brings new challenges in creating a secure and reliable data storage and access facility over insecure or unreliable service providers. The integrity of data stored in the cloud is one of the challenges to be addressed before the novel storage model is applied widely. In this paper, we propose a remote data integrity checking protocol based on HLAs and RSA signature with the support public verifiability. The support of public verifiability makes the protocol very flexible, since the user can commission the data possession to check the TPA.

Private-preserving shared dot product protocol is an important protocol of many secure multi-party computation problems. It has been the main building block of various data mining algorithms with privacy concerns, and providing fundamental security guarantee for many privacy-preserving data mining algorithms. In this paper, we construct a privacy-preserving two-party shared dot product protocol based on some basic cryptographic techniques which is provably secure in malicious model; this protocol has more security than those of previous protocols in the semi-honest model. The potential areas of application of this protocol are numerous, for example, computation of Euclidean distance, privacy-preserving computational geometry, privacy-preserving cooperative statistical analysis and so on.

The integrated system of design for manufacturing and assembly (DFMA) and Internet-driven collaborative design was presented to support product design, manufacturing process, and assembly planning for product. The system managed and scheduled group oriented collaborative activities. The design guidelines of Internet-driven collaborative design & DFMA were expressed. Product design and assembly planning can be operated synchronously, intelligently, integrated under the condition of Internet-driven collaborative design and DFMA. The technologies of collaborative modelling, collaborative manufacturing, and Internet-driven collaborative assembly for the pump were developed, which was an example.

In this paper we address the important issue of providing QoS for VBR video communications in an efficient manner. We show that efficient transmission of VBR video with a high QoS is feasible when using a receiver-initiated resource renegotiation (RIR) scheme. The scheme for RIR is based on RTP and RSVP. RTP's media specific header is used to send video source information to receivers. Receivers utilize this information to estimate the traffic descriptors. Renegotiations are triggered based on the receiver's buffer status and RSVP is used to renegotiate flow parameters with the network. The performance of the proposed scheme is evaluated via simulations using several 20-minute-long MPEG-2 bit streams. Performance metrics considered are video quality and renegotiation overhead for different receiver buffer sizes and network delays. The results show that the proposed RIR scheme provides high video quality with an average renegotiation interval on the order of seconds, a 5-15 frames receiver buffer and network renegotiation delay below 300 msec. We also investigated call admission control (CAC) schemes for renegotiation VBR services. In particular, we studied the performance of the Central Limit Theorem based and the Chernoff bound based CAC algorithms, in terms of error in the calculation of the maximum number of admissible connections. Finally, to facilitate the scaling of the renegotiation scheme to large-scale networks, we studied how to reduce renegotiation overhead.