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Coalbed methane (CBM) which is a kind of efficient and clean unconventional natural gas will be the alternative energy in the future. The studying degree of predecessor is low to the pore-fracture structures of coal reservoir in Hancheng Mining area, Ordos Basin, China. It has been researched with some tests and the results are as follows: micropore is more, specific surface area is larger, throat radius is lesser, permeability is low, but the pore - fracture is development, phenomenon of mineral filling pore - fracture is widespread, sorting features of throat radius is better. From the point of test results, physical property of coal reservoir in the study area is good,which is suitable for the exploration and development of coalbed methane resources.

Detection of moving object is a hot topic in computer vision. Traditionally, it is detected for every pixel in whole image by Gaussian mixture background model, which may waste more time and space. In order to improving the computational efficiency, an advanced Gaussian mixture model based on Region of Interest was proposed. Firstly, the solution finds out the most probably region where the target may turn up. And then Gaussian mixture background model is built in this area. Finally, morphological filter algorithm is used for improving integrity of the detected targets. Results show that the improved method could have a more perfect detection but no more time increasing than typical method.

Coalbed methane (CBM) which is a kind of efficient and clean unconventional natural gas will be the alternative energy in the future. Deformed coal which is harmful to CBM development was studied with logging curve. The logging curve characteristics and template which can be used directly had been put forward and applied in Shizhuang Block, Qinshui basin, China: (1) Deformed coal has low resistivity, low bulk density, high interval transit time, expanding well diameter and increasing neutron porosity in logging curve. (2) 3 type coals (undeformed coal-transitional coal - deformed coal) are arranged from lower-left corner to top right corner in order in AC and LSD diagram. (3)The deformed coal proportion of No.15 coal is significantly higher and it maybe the main restricting development factor. (4) The northeast and southwest of Shizhuang block have more deformed coal.

Image matching plays an important role in computer vision. The features extracted by SIFT algorithm have high stability invariant to scale, rotation and light, so it is the most popular algorithm for image matching. While SIFT algorithm also has its disadvantages of high dimensional data and time-consuming. To solve this problem, the traditional method employs PCA algorithm to reduce dimensionality of the descriptors. While PCA is a linear dimensionality reduction algorithm which means that it can only be used for linear distributed data. This paper employs the fuzzy K-means algorithm to improve it (referred to as FKPCA) and improved RANSAC algorithm to eliminate false matching points after matching with PCA-SIFT and FKPCA-SIFT. From the experimental results, compared with PCA-SIFT algorithm, it can be seen that FKPCA-SIFT can keep the high matching accuracy for image. Moreover, FKPCA-SIFT can also be applied to non-linear data to expand the scope of PCA-SIFT and provides a better reference platform for further research.

This paper presents a new algorithm of image matching via combining sift and shape context for improving image matching accuracy. A joint descriptor is applied to describe feature points. The initial matching is obtained by a proposed distance formula. Furthermore, PLS is introduced to eliminate mismatched points. Experimental results demonstrate the proposed algorithm can achieve better performance compared to conventional methods.

Golden Guanyin tea from Lishui city, Zhejiang province, is a new variety of Oolong tea with special aromas. To analysis the aroma compounds, two sample preparation methods of tea grinding and water distillation were carried out, then the tea aromas and amino acids were detected. The main aroma compounds were of dimethyl sulfide, butanal, ethyl acetate, butanedial and cyclobutene by the grinding method, as for the distillation method, the aroma compounds detected were of benzeneacetaldehyde, phenylethyl alcohol, benzyl nitrile, Geraniol, indole, cyclopentene, phenylethyl butyrate, nerolidol, methyl jasmonate, 2,2'-dipyridylamine, benzenedicarboxylic acid, cyclopentaneacetic acid, methyl jasmonate ester, dibutyl phthalate and phytol. Golden Guanyin tea samples had 16 kind amino acids, in which glutamic acid and leucine were of 0.047 and 0.041 mg/mL, respectively, and the minimum ones were of cysteine and methionine in concentration of 0.004 mg/mL. The results will be helpful in the quality improvement and production of the new Golden Guanyin tea.

Local planning is of great importance to intelligent vehicle driving at high speed where the traffic environment is complex. The local planning must satisfy the performance of good real-time and guarantee feasibility and safety. In this paper, a novel local planning method based on the optimization of curve generation and selection is proposed. By optimizing the curve parameter model, we can get the feasible path which is satisfied with vehicle dynamics constraints. Then taking into account the obstacle constraint, we apply this method to generate a cluster of candidate paths used for tracking global path. Next, we use optimization indicators presented in this paper to choose the suitable desired local path. Experimental results show that: using our method, the change in the curvature of the generated desired local path is slight and it meet the requirement of safety and control smoothness. Besides, this method can satisfy the meeting of tracking global path. What’s more, in real traffic environment, this method reflects a good performance in real-time and safety.

A feedforward and feedback path tracking algorithm appropriate for automatic parking is proposed in this paper. This algorithm is composed of feedforward control and feedback control. In the path tracking, vehicle position and reference path information are used to calculate the lateral and heading error of the vehicle as well as the curvature of reference path, and put these three as the system inputs, the steering angel of the vehicle as the output. The system parameters are settled by multiple tests. Experiments show that, this method has a high performance in path tracking and meets the requirements of vehicle parking in both low speed situation and narrow spaces.

For the problem of balance bearing of universal spindle in rolling mill being prone to damage, the paper established mechanical model and finite element model of universal spindle. The paper has analyzed that the shear and bending moment in the middle of the shaft is the largest. The fillet near shoulder of balance bearing of the spindle is dangerous part. In order to reduce principal stress of universal spindle caused by moment, the paper improved balance mode of the spindle. The equilibrant was applied from in one place of shaft to put in two places. After optimizing, equivalent stress of the spindle is slight smaller than before under the same loading condition, which illustrates that the strength of the spindle is appropriately improved. Although the effect is not obvious, this has played a guiding role for the optimization of balance mode of universal spindle.

Microorganisms in aquatic ecosystems play an important role in the processes like water purification, nutrition regeneration and biochemical circulation. Some microorganisms are also related to human diseases. To analyze the main microorganisms in the water systems in northern Hangzhou, water was sampled from three different rivers for isolation and identification of microorganisms. The highest diversity and quantity of bacterium was found in the rivers in Banshan industrial district, with an average 127 clones in each plate. For the Beijing-Hangzhou Grand Canal and Longshan reservoir, the number was 20 and 7, respectively. Similar trends were also observed for actinomycetes and molds. CCA analysis showed that the microorganism abundance was mostly related to the NO3-N, TP and TN values of water. Totally, 7 bacterium strains were identified, includingBacilluscereus,Escherichiacoli.,Klebsiellapneumoniae, and so on, which belong to 7 different genera. In an antibiotics sensitivity analysis, all of the 7 bacteria showed sensitivity to tetracycline.

An improved pure pursuit path tracking algorithm is presented for a four-wheel steering (4WS) carrier vehicle to follow a desired path automatically. A bicycle vehicle model considering the 4WS carrier vehicles structural and steering features is applied in the method. Real vehicle tests in an open large outdoor warehouse showed that the lateral tracking error was less than 0.56m at 20km/h. And we can conclude that the enhanced method for 4WS vehicle has good tracking ability on flat road.

CNOOC laid offshore oil and natural gas pipelines for offshore drilling platforms. The engineering included laying the pipelines from offshore drilling platform to landing zone, laying the pipelines between two platforms, and installing vertical pipes for platforms. Aiming at the characteristics in the diving project management, this paper analyzes and evaluates the difficulties and risks of underwater work, puts forward the corresponding safety managements. These measures ensure the underwater operations safely and smoothly. The engineering lasts 195 days, uses 160 diving equipments, and dives 282 person-times. The total diving time is 17900 minutes, and the maximum diving depth is 70 meters.

A lot of plants have been confirmed to be capable of purifying water. To screen for plants for water purification in the Xixi wetland, water was sampled from the Xixi wetland for indoor experiment. Four kinds of aquatic plants of different growth type (Eichhornia crassipe, Ceratophyllum demersum, Acorus calamus and Lemna minor) were selected for culture using the water under test. After 45 days of culture, obvious water quality improvement was observed for all of the plants. The BOD5, COD, TN and TP value of the water was decreased by 64.80%, 58.73%, 87.52% and 90.06%, respectively by the plants in the experiment. Based on a comprehensive analysis, Eichhornia crassipe and Ceratophyllum demersum showed high efficiency in water purification. Therefore, these two kinds of aquatic plants are suggested to be planted more in Xixi wetland.

With the era of big data approaching, data becomes more and more important. Faced with such massive amounts of data space, how to quickly identify the contents of a field that the users are interest in and extract them out, is an urgent problem to be solved. To identify the content that users are interested in, we can use NLPIR Chinese word segmentation framework for speech segmentation, and identify named entity according to part of speech tagging. For extraction, using Hadoop, parallel cluster platform based on a big data MapReduce framework, using the Hadoop Distributed File System (HDFS) for efficient data access and starting Map and Reduce tasks to extract the information of named entity. This task extracts the required information from the interactive encyclopedia and then stores them in the knowledge base. It implements the task of extracting the information data of parallelization of named entity based on Hadoop platform.

Ontology and semantic are very popular in Web, and the construction of Web dynamic ontology has been the problem urgent to be solved. Firstly, the basic framework for constructing Web dynamic ontology is shown. Next, the concept lattice is introduced, based on which the novel method of building Web dynamic ontology is given. It includes constructing the initial ontology, extracting web knowledge, generating the formal contexts, merging formal context, merging concept lattices with ontology-based similarity calculation, transforming the concept lattice to the ontology. At last, the stock information system is employed to verify the methods proposed. The results showed the stock ontology could be dynamically updated with the change from the Web, and we can get new inferred knowledge from the updated stock ontology by Racer; the method proposed is valid and feasible.

In order to reduce computational complexity of modeling and improve the model's robustness and prediction accuracy, successive projections algorithm is used in the Neural Networks calibration modeling of wheat protein. Firstly, the spectral data is pretreated with first-order differential method and SNV method，and then a representative set of calibration samples are selected by SPXY algorithm. Secondly, making use of successive projections algorithm(SPA) to extract sensitive wave points of the original spectrum and the pretreated spectrum, and then the neural networks calibration model of wheat protein is established. The results show that the calibration model based on successive projections algorithm has a fast convergence speed and high accuracy, both of which are better than the calibration model established with the original data. Root mean square error of prediction(RMSEP) and prediction correlation coefficient(r) are 1.3332 and 0.94319 respectively, which can basically complete the grain reserves and the food processing profession division and the breeding preliminary generation.

Semantic similarity measure has always been one of the important contents in artificial intelligence. This paper puts the ontology as the research object, and measure the semantic similarity between two ontologies in view of concept lattice. Firstly, concept lattice is introduced to similarity measure, and the thought of the ontology-based semantic similarity measure with concept lattice was given. Next, the solution of the measure was described, which includes generating a formal context of heterogeneous ontologies, constructing the corresponding formal context of formal context to fetch the formal context in concept lattice, and using irreducible infimum theory to calculate the similarity value of heterogeneous ontology concept. Finally, we employed a sample to verify the measure method. The results showed the method can effectively compute the semantic similarity between the ontologies, and the method proposed is valid and feasible.

Modern services are becoming polarized. With the emergence of more and more automatic terminal services, modern services are also gradually becoming unmanned. The automatic medicine vending machine exactly emerges under the background mentioned above. The emergence of automatic medicine vending machine can reflect the reform of China’s existing medical system to a certain extent, solve the tense supply-demand relationship between doctors and patients in China, and help some patients to achieve self-improvement and self-healing without going to the hospital. For that reason, based on the principle of ergonomics, this paper will probe into and analyze how to design more humanized automatic medicine vending machine to better fit people’s practical requirement.

Perfluorinated compounds (PFCs) are man-made fluorinated hydrocarbons, which are very persistent in the environment. Being the most important PFC, perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) have received much attention. According to the large production volume and wide usage in industrial and commercial products in the past, PFOS and PFOA can be detected in various environmental media and matrix, even in human tissues. This paper attempts to review the current status of PFOS and PFOA contaminations in Asia, focusing on a variety of water systems, including surface waters, drinking water, coastal water and sea water. The current information suggests that PFOS and PFOA were replacement compounds identified, although PFC species detected were not completely the same in different water systems. The information also suggests that drinking water might be an important source of exposure to PFOS and PFOA, and continued human exposure to even relatively low concentrations of PFOS and PFOA in drinking water may result in elevated body burdens that may increase the risk of health effects.

Repairable system is complex, because of its diversity distribution form of units’ lives and its complex structure. In this paper we studied on a complex system. Lives and repairing time of units obey general distributions, we got the unit transient availability by using Markov renewal process, then got the system transient availability by using the character of coherent system. Finally gave example which verified by Monte Carlo method. This paper provided calculation base for more complex system.

To evaluate the toxic effects of environmental contaminant PFOS on green algae, Scenedesmus obliqnus was cultured in media containing serially diluted PFOS for evaluation of proliferation capacity and some physiological indexes. Within 96h, PFOS doses ≥50 mg/L all inhibited the proliferation speed of Scenedesmus obliqnus(p

In the ever-increasing development of network storage technology, distributed RAID has been a hot topic for data reliability and availability. To solve the problem of distributed RAID technology, such as: parallel access difficulty, long rebuild time, small write update and strip alignment problem, we design and implement file level distributed RAID system (BW-FILERAID) based on Blue Whale File System (BWFS). Also we do the research on resource allocation strategy, page cache management with parity data, consistence maintenance, online extension of RAID group, error detect and rebuild and small write optimization in BW-FILERAID. According to the testing results, the writing performance of BW-FILERAID is better than Linux soft RAID about 5%~50%, and the reading performance is equivalent to the RAID0. And it also has excellent extensibility.

Finite element method with experimental data was used to calculate and analysis the temperature field and machine assembly of a 150 engine cylinder liner. Using a series of evaluation criteria such as maximum, minimum radius, light leakage rate to analyze the influence of the main structural parameters on the cylinder liner deformation in the coupling effect of Thermal stress and mechanical stress. Comparative results show that: increasing the wall thickness of cylinder liner can reduce the radial deformation of the cylinder liner effectively, the diameter of the cylinder liner shroud has little effect on the cylinder liner radial deformation, but it can reduce the local stress concentration of the cylinder liner, cylinder shroud thickness increases can lead to the radial deformation of the cylinder liner increasing.

Normally there is the very huge dataset in the application of medicine and bioinformatics. Traditional association algorithm produces too many rules in this kind of application, which are difficult to be identified and compared. In this work we attempt to propose an extension of Apriori algorithm to explore individualized treatment optimization of breast cancer. As the result of our method, the comparative association rules are produced. Thus, association rules algorithm become more practical and useful, especially in the field of medicine and bioinformatics.