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In BitTorrent network, how to avoid free-riders is an in inevitable problem of improving BitTorrent performance. Using trust management is a trend of P2P transmission. We propose a combine trust management scheme, combining local trust value and trust value from neighbors to calculate a combine trust value. The combine trust value represents the spread of reputation in the BitTorrent network. Through the combine trust value, peers could recognize the free-riders. Experiment results prove that compare combine trust management scheme with local trust management scheme, the combine trust management could avoid more free-riders, thus has better download performance.

Engineering science is bridge of fundamental science and engineering. This paper introduces origin, growth and figuration of engineering science by examining its history, and defines it as science-based engineering theory, or science-abstracted engineering theory by comparing concepts related. Finally, roles, which engineering science play for a nation, are discussed including increasing productivity, providing solutions for national security, and advancing science and technology. The authors suggest more recognition of fundamental science, talent cultivation from Chinese perspective.

To solve the high startup delay and playback delay in P2P streaming system which are caused by peers randomly join or leave the network, we proposed a neighbors acquiring method. This paper presents the details of our neighbors acquiring method. We use tracker server to grasp the information of all nodes in the P2P network. Based on these information, tracker server could pass proper neighbor nodes to the peer node which request neighbors from tracker server through evaluation process. Some conditions are involved in the evaluation process, like node activeness, bandwidth, time nodes existing, buffer-map matching. We estimate our neighbors acquiring method through a P2P streaming system simulation. The simulation results show the P2P streaming system which uses our neighbors acquiring method has lower startup delay and playback delay than the P2P streaming system which uses random neighbors acquiring method.

Based on safety assessment factors determined by operation characteristics of a certain tailing ,genetic BP neural network evaluation model is established. To overcome such problems of BP neural network as slow convergence ,poor generalization ability and easy to fall into local minimum value,this paper proposes to use genetic algorithm to optimize threshold value,weights and structure of neural network. Thus,by taking advantage of extensive mapping ability of neural network and global search ability of genetic algorithm,neural network and genetic algorithm will have complementary advantages and the learning speed of network will be accelerated. The application of the described method shows optimized fitting precision,improved accuracy and efficiency ,and enhanced generalization ability of BP neural network. In conclusion,this model can effectively reflect and accurately evaluate non-linear relations between security levels and evaluation factors in tailing.

The cone penetration test (CPT) for loess-like silty clay soil in western Henan province was done to obtain the tip resistance and sleeve friction. Then, the relationship of CPT and physico-mechanical parameters of loess-like silty clay soil was analysis. At last, the empirical model for physico-mechanical parameters of loess-like silty clay soil in western Henan province was established. The physico-mechanical parameters of loess-like silty clay in western Henan province could be calculated by sing the empirical model from CPT, including water content, void ratio, plasticity index and compressibility coefficient. The results provide the foundation for reliability analysis of parameters of loess-like silty clay soil in geotechnical investigation, design and construction.

Small and medium hydropower projects have to be suspended due to various reasons. Paper tries to study it as the perspective of entropy. With systems theory and entropy theory, paper defines the concept of project finance entropy. Through PROT project financing entropy analysis of the causes and mechanisms, it established entropy mathematical model of PROT project financing. And through the model, paper makes a detailed analysis of project financing entropy evolution mechanism.

Earned value management is a prerequisite for the wide range of applications in the practice of project management at home and abroad. In this paper, As to the quality of the target cost and schedule goal, To the project cost and schedule performance evaluation, On the basis of reading the relevant literature and researching at home and abroad. Using theory and method, which cost and schedule performance evaluation of earned value management as the research object. Application of project management software, It is greatly meaningful to applying earn value management model to small and medium-sized hydropower stations project.

Currently, the embedded database technology has become a very active research field, and attracted more and more attention. This paper research how to improve the storage performance of embedded database indexing mechanism using read and write characteristics of NAND flash memory. Based on the reviewed and compared of existing design of NAND flash memory, this article expressed the design and implementation of dynamic index mechanism base on B + Tree. The prototype system combines the advantages of operation of the adapted read operation disk model and write adapted write operation log model, optimal matching and converting for storage model of each node in B + tree model while running which make a variety of devices have better read and write performance.

Since the physical characteristics and access mode of flash memory both have significant difference with disk, storage management research become the basis and key factor of flash memory database, the performance of storage management often directly impacted on the performance of other subsystems in flash memory database system. Against the characteristics of database data access and problems of existing methods, this paper presented an adaptive flash memory management method which improved performance of data updating in flash memory while taking into account of the better read performance.

Along with the development of Internet of Things (IOT), there are a lot of increasingly serious security problems. The traditional intrusion detection method cannot adapt to the requirement of IOT. In this paper we advance a new intrusion detection method which can adapt to IOT. It is based on Hidden Markov Model (HMM), which is named as Hidden Markov state time delay sequence embedding (HMMSTdse) method.

Intrusion detection system (IDS) can find the intrusion information before the computer be attacked, and can hold up and response the intrusion in real time. Artificial neural network algorithms play a key role in IDS. The intrusion detection system (ANN) algorithms can analyze the captured data and judge whether the data is intrusion. In this paper we used Back Propagation (BP) network and Radical Basis Function (RBF) network to the IDS. The result of the experiment improve that The RBF neural network is better than BP neural network in the ability of approximation, classification and learning speed. During the procedure there is a large amount of computes. On cloud platform the calculation speed has been greatly increased. So that we can find the invasion more quickly and do the processing works accordingly.

In this study, a novel structure design method based on knowledge template was prompted. The notion and construction methods of knowledge template were introduced. Moreover, the knowledge template based design process was represented. The knowledge templates of investment casting die bases of turbine blade were established and a design system for die base was developed. The system provides designers with a semi-automated approach for the die base design. Finally, several sample applications for investment casting die base of turbine blade were presented for demonstration.

Under the context of airplane deicing, this paper aims to do a research on the unrelated parallel scheduling of service resources with flexible time window. To deal with more tasks, minimizing delay time is chosen to be the objective of the mathematical model and a modified ant colony algorithm is given. With full consideration of the practical problem and constraints, update policy of pheromone and settings of heuristic factors are suggested. The feasibility and rationality are proved by a simulation example. The modified ant colony algorithm outperforms FIFO method and could be well applied in the unrelated parallel scheduling issues with flexible time window.

Under the context of deicing in the airport, and in order to solve a kind of Non-identical Parallel Multi-machine Schedule Problem for minimizing the number of passengers delayed, an ant colony algorithm was proposed. Considering the characteristic of scheduling model and its constraints, an improved pheromone update strategy was developed by deploying different parameters. Simulation was made for proving the effectiveness of the algorithm, and the sensitivity analysis was conducted. Besides, the improved ant colony algorithm was compared further with FIFO algorithm used in realistic backgrounds. In all, the result indicated that the improving ant colony algorithm was valid, and it can fit for large-scale non-identical parallel Multi-machine scheduling problem.

In order to improve the mining benefit of coal resources, Chang Gouyu Coal Mine carried out the technology of mining without coal pillar in steep seam. The key of the technology was to ensure a long-term stability of the cross-entry roadway across the seam. Through the analysis of the nature of steep seam roof and floor rock, and based on the stability analysis and loose circle measured of surrounding rock of crosscut roadway, we brought forward adopting shotcrete rockbolt mesh and U-shaped steel complex support structure system. This complex support system could flex lengthways and compress in radial direction. The entirety integrated with the surrounding rock, and they formed into a whole. Application of the complex support system could effectively control the deformation of the surrounding rock collapse, and maintain the stability of the crosscut.

The effect of operating conditions on the performance of a CTAB modified resin column used for the treatment of steel rolling oily wastewater was investigated. The influence of flow rate, influent oil concentration, fixed column height and influent pH was studied. Experimental results showed that several processes were involved in oil removal from rolling oily wastewater, i.e. emulsion breakdown, coalescence and adsorption. More than 95% of oil content in the influent stream was removed by the modified resin column and it increased by 15% compared with the unmodified resin column.