Key Engineering Materials Vols. 439-440

Abstract: In order to monitor industrial parameters such as the temperature, pressure, and humidity more intuitively, an embedded multi-channel data acquisition system is designed in this dissertation. These collected data need to be stored safe to prepare for the further process. Therefore, a SD memory card system is specially designed. In the system, the LPC2210 is selected as the controller and FAT32 is adopted as its file system. This design will provide a convenient and reliable solution for industrial field data acquisition and storage.

Abstract: In this dissertation, the theory, mathematical model and algorithms on the Multilayer Situation Decision-making are firstly introduced. And then the design and implementation of the Multilayer Situation Decision Support System based on MATLAB GUIDE are presented. In order to achieve the purpose of both testing the performance of the DSS and solving the optimization problem of the Hebei Provincial economic system, the empirical analyses are put forward afterwards. In the end, some suggestions for the policymakers are also proposed.

Abstract: Using the theory of explosion mechanics and gas detonation dynamics and the conservation law of mass, momentum and energy, the physical and mathematical models of damage effect are set up in excavation roadway during gas explosion. In view of gas concentration, accumulation position, volumes and states of spaces, the shock wave damage on structures in the roadway during gas explosion. The damage effects are characterized of heat and mechanic damage. Meanwhile, the high temperature and pressure are formed in different degree. With the action of overpressure and impulse, the damage degree is different with different geometric structures in ventilation system. By means of basic condition, influential factors, procedure features and simulation, some unnecessary structures or barriers should be cleared in order to keep smooth the ventilation system.

Abstract: The physical and mathematical turbulence flow fields models are set up to numerically simulate railway tunnel fire and smoke flow. An experimental fire simulation results in railway tunnel indicate that the temperature distribution of laminar flame, the smoke concentration and flow velocity can be expressed by the fully developed smoke flow downwind. Through numerical simulation, it is concluded that the turbulent flow field models are better and have good consistency with the experimental results. The phenomenon of tunnel fire, the development and distribution of smoke flow can not only provide great support on the fire protecting and ventilation plan, but also give better reference to the pedestrian evacuation and the design of disaster prevention and mitigation.

Abstract: Coal mine can be damaged by extremely strong methane explosion, and the importance of suppressing anti-methane explosion in coal mine production safety is self-evident. The basic assumptions are used to analyze the shock wave propagation and the strength characteristics during methane explosion. The expressions among parameters in wave-front are derived during strong and weak shock wave propagation. Meanwhile, the cylinder shock wave overpressure parameter while propagating and attenuating with distance is deduced. In a certain distance away from the source location of explosion, the overpressure are basically in inverse proportion to the square root of the distance and laneway section, and is proportional to the square root of the amount of pure methane involved in the explosion. Through comparison and analysis of theoretical calculations and numerical simulation data, the data are almost identical.

Abstract: Detection of pathogenic microorganism is very necessary in the control of infectious disease prevailing in aquiculture animals. However, most of the present techniques can not meet the need of the quick field inspection. Systematic evolution of ligands by exponential enrichment (SELEX) is a new molecular recognition way for generating high affinity oligonucleotide acid aptamers, a new nucleotide acid material, which have been widely used in the detections of proteins, cells and so on. In the present paper, the technology was applied to select the high affinity aptamers against pathogenic microorganism Vibrio alginolyticus, which could be used for the rapid field detection of the microorganism. Based on the designment of the ssDNA library of 76 nucleotide acids with 35-base random region, the SELEX system for the selection of the high affinity aptamers against Vibrio alginolyticus was established. In the SELEX system, asymmetric PCR was proved to be a better amplification method for the ssDNA library than the reported affinity magnetic bead method, and the corresponding parameters of the asymmetric PCR were also studied and optimized. The affinity of the final ssDNA library increased by nearly 200% compared with the original library. Cloning and sequencing of the final ssDNA library showed that there were at least two kinds of ssDNAs with different length in the affinity ssDNA library: one was 76 bases, another was 149 bases. Simulation of the secondary structures showed that the secondary structures of the two fragments were different greatly, suggesting that the two fragments could bind to different sites of V. alginolyticus surface.

Abstract: In IEEE 802.16e network, voice over IP (VoIP) scheduling is critical to system performance but no special algorithm is defined in the IEEE 802.16e standard. Based on this thinking, a novel VoIP scheduling algorithm named compensated based VoIP scheduling (CBVS) is proposed. This algorithm compensates the bandwidth of service flow whose bandwidth is lost using the remained bandwidth. The simulation results show that the proposed algorithm improves the performance much and increases the number of VoIP users.

Abstract: The measurement of worker differences is fundamental consideration in personnel assignment which is one key decision that influences the productivity and quality of assembly production. Due to the weakness of presented researches on worker differences measurement, the concept of station fitness, which takes the worker skill level and accumulated execution time in a given period as parameters, is proposed to better describe the worker competency and provide a way of measuring the differences among workers. A personnel assignment optimization model based on station fitness for assembly production is constructed, and the objectives are maximizing the station fitness for each assembly station and minimizing the difference of station fitness for workers assigned in the same assembly line. Then a heuristic algorithm based on the fitness matrix is presented to solve this model. The results from the example demonstrate the feasibility of the approach.

Abstract: Automatic target recognition is the key stage of SAR image interpretation system and has been taking a great interest to the researchers in recent years. Aiming at the issue of aircraft type recognition in high-resolution SAR images, a novel method based on multi-scale autoconvolution (MSA) affine invariant moment is proposed. First, the texture analysis and clustering method are used to segment the SAR images and then the denoising algorithm and morphological processing are applied to segmented results. Second, 29 MSA features are extracted and form a feature vector to represent the target, then the vector components are standardized by gauss normalization. In the final, the vectors are classified by using the nearest neighbor classifier and template library constructed previously. Experimental results show that the proposed method can obtain high accuracy rate with high processing speed, in which the accuracy rate of two type aircrafts with real data arrives at 85.17% and the accuracy rate of four type aircrafts with simulated data arrives at 87.85%.

Abstract: HITS algorithm assigns same weight to links between Web pages,which results in topic drift. In this paper,a new focused crawling approach based on PSO Algorithm is proposed（PSOHITS）. The method electively seeks out pages that are relevant to a pre-defined set of topics using PSO Algorithm,increases the crawling chance of the web page following the web page with the low content-relevance,and broadens the relevant-searching scope of crawlers.Meanwhile,the hyperlink metadata is used to predict the topic-relevance of the web page pointed and quickens the information crawling. Experiments show that the proposed algorithm can improve relevance ratio by 15%~36%.Furthermore,it can well avoid topic drift and improve the accuracy of information collection. It has important theoretical and practical values for search engines research.