Partitioning characteristics of gas channel of coal-rock mass in mining space and gas orientation method

In order to research the influence of coal-rock mass morphology of mining space on the flow law of gas,the laboratory physical model and numerical computation methods were adopted to simulate coal mining activities.The simulation results indicate that,after coal seam mining,the loose rock accumulation body of free caving,ordered rock arrangement body of plate damage rich in longitudinal and transverse fractures and horizontal fissure body formed by rock mass deformation imbalance are formed from bottom to top in the mining space.For these three types of accumulation bodies,there are essential differences in the accumulation state,rock size and gas breakover characteristics.According to this,the coal-rock mass in the mining space is classified into gas turbulence channel area,gas transitional flow channel area and gas seepage channel area.In the turbulence channel area,the gas is distributed transversely and longitudinally and gas diffuses in the form of convection with Reynolds number R_e more than100;in the transitional flow channel area,one-way or two-way gas channels are crisscross and gas is of transitional flow regime with R,.between 10 and 100.In the seepage channel area,there are a few vertical gas channels with R,.less than 10.In this paper,the researches on the gas orientation method in different partitions were further carried out,gas orientation methods of low-level pipe burying,middle-level interception and high-level extraction were determined and an on-site industrial test was conducted,achieving the effective diversion of gas and verifying the reasonableness of gas channel partition.

A NEW KOSSEL ORIENTATION METHOD OF CRYSTAL

A new Kossel orientation method of crystal is developed.Only the distances among three in- tersections of the Kossel lines on the indexed Kossel patterns observed are necessary.for de- termining the orientation.Thus,the error may be eliminated and the orientation precision may be improved to be within 0.3°.

New Refinement Relations of Z Specifications for Multiple Viewpoints Oriented Requirements Method

In this paper we develop several new refinement relations of Z for multiple viewpoints oriented requirements method (MVORM). The original motivation is that we found the standard Z refinement relation is not adequate or correct when considering specifications that have temporal relationships of operations. The concept of temporal state variables is introduced into Z. Then new implementation relations are defined and new refinement relations are deduced, mainly for temporal state variables to process temporal relationships of operations. We use state transition systems to abstract the temporal state transitions. A simple example is used to show the procedures of MVORM. Finally some directions of further work are forwarded.

Two Generic Frameworks of Multiple Viewpoints Oriented Requirements Method and Their Comparison

Traditional requirements method has some problems when it is used for large distributed systems. Multiple viewpoints oriented requirements method (MVORM) is a new method for resolving these problems. This paper develops two generic formal frameworks of MVORM, framework based on refinement relation (FBRR) and framework based on implementation relation (FBIR). They are generic, because no assumptions are made about the development process or the formal description languages to be used. Three kinds of specification relations and three kinds of specification transformations are discussed over FBIR and FBRR. This paper also compares the equivalence between FBIR and FBRR. We point out that an equivalent FBIR can be found for any FBRR, but reverse transformation is not always possible. We think FBIR is better than FBRR on most cases.

Temperature Field Reconstruction in High-Temperature Gas by Using the Colored Background Oriented Schlieren Method

A 3D temperature field reconstruction method using the colored background oriented schlieren(CBOS)method is proposed to address image blurring due to the different refractive index of the multi-wavelength light and significant errors produced when the traditional background oriented schlieren(BOS)method is applied to high-temperature gas.First,the traditional method is employed to reconstruct the non-uniform 3D temperature field.Second,the CBOS method is applied to correct the distortion.Then,by analyzing the correlation coefficient among different color points of the colored background pattern,the non-uniform temperature field is reconstructed much more accurately.Finally,the experimental results are verified by applying the Runge-Kutta ray-tracing method and the thermocouple contact measurement method.The maximum average temperature error of the CBOS-reconstructed temperature field is 12.92°C,compared with the thermocouples.Therefore,an accurate three-dimensional reconstruction of the temperature field can be achieved by the proposed method effectively.

An efficient and rapid method to detect and verify natural antisense transcripts of animal genes

High-throughput sequencing has identified a large number of sense-antisense transcriptional pairs, which indicates that these genes were transcribed from both directions. Recent reports have demonstrated that many antisense RNAs, especially lnc RNA（long non-coding RNA）, can interact with the sense RNA by forming an RNA duplex. Many methods, such as RNA-sequencing, Northern blotting, RNase protection assays and strand-specific PCR, can be used to detect the antisense transcript and gene transcriptional orientation. However, the applications of these methods have been constrained, to some extent, because of the high cost, difficult operation or inaccuracy, especially regarding the analysis of substantial amounts of data. Thus, we developed an easy method to detect and validate these complicated RNAs. We primarily took advantage of the strand specificity of RT-PCR and the single-strand specificity of S1 endonuclease to analyze sense and antisense transcripts. Four known genes, including mouse β-actin and Tsix（Xist antisense RNA）, chicken LXN（latexin） and GFM1（Gelongation factor, mitochondrial 1）, were used to establish the method. These four genes were well studied and transcribed from positive strand, negative strand or both strands of DNA, respectively, which represented all possible cases. The results indicated that the method can easily distinguish sense, antisense and sense-antisense transcriptional pairs. In addition, it can be used to verify the results of high-throughput sequencing, as well as to analyze the regulatory mechanisms between RNAs. This method can improve the accuracy of detection and can be mainly used in analyzing single gene and was low cost.

Practical Discussion of Output Oriented Method in English Major Teaching

China’s education has always been the focus for all sectors of society,and the education reform has been going on an in-depth process.Therein English major has made good progress in teaching reform,and is the focus for the education sector and the public.At present,colleges and universities in our country are facing some prominent problems.They are the phenomena that many colleges and universities have always attached great importance to language education and paid not enough attention to the ability of language communication,and paid too much attention to the explanation process and lack of training.Only the overall reform and development can make the teaching effect reach a satisfactory level.By promoting students to obtain good achievements,we can carry on longterm development in the new background and new era.Output oriented method is a new word with strong timeliness.It can improve the comprehensive quality of students to a certain extent.At the same time,it can promote the teaching quality in a certain sense,and has a positive role.

Virtual Organization Information Systems and its Reengineering for Agile Manufacturing

It is now possible to organize globally while worki ng locally: Information technologies like e-mail, the Internet, and video confere ncing to the desktop permit tight coordination of geographically dispersed worke rs across time zones and cultures. Companies are not limited to physical locatio ns for providing products and services. Networked information systems are allowi ng companies to coordinate their geographically distributed capabilities as virt ual organizations. In order for organizations to succeed, they must be able to r espond with agility in a geographically dispersed environment. The core for a vi rtual organization to increase the utilization rate of resources to the maxi mum and to make full use of the transient market opportunities lies in how to br ing the potential of information technology into play. Based on the philosophy o f agile manufacturing, this paper analyses the basic concepts and connotation of Virtual Organization Information systems(VOIS). VOIS is an information system composed of some independent information subsystems that are autonomous, collab orative and belong to umpty organizations respectively. VOIS support the operati on of virtual organization, and automate the information flow across organizatio nal boundaries. Such systems have capabilities as rapid construction, quick oper ation, and agile reengineering and swift adaptability. Differences between VOIS and traditional enterprise information systems are analyzed. On the basis of ana lyzing the structure of VOIS, an abstract hierarchical structure of VOIS is prop osed using object-oriented method. Reengineering ideology and methods of VOIS a re also explored in light of the three layers structure.

Optimization method for star tracker orientation in the sun-pointing mode

The star tracker is an optical attitude sensor with extremely high accuracy, the structure of which is mainly composed of the baffle, the lens, the image detector, and the processing unit, and it has been widely used in satel- lites To realize attitude determination from the weak star captured by the image detector of the star tracker,

Teaching Proficiency through Reading and Storytelling

Human beings are wired for stories.Throughout our existence,stories have been an integral part of our meaning making,and informational transportation.Stories are embedded in our biology.We do not just tell stories and hear stories,we experience stories emotionally and cognitively,and we feel stories physically in the body.Stories have been used in every aspect of human life,and have always been part of language teaching as well.Researches have shown that narrative films and readings help to develop empathy,perspective taking,understanding ourselves and others and increase literacy.TPRS is a fun and effective method in teaching foreign languages in a classroom setting.It takes advantage of the power of story in comprehensible input-oriented method.This paper describes what is TPRS and how it works.

Study on the Source Management and Analysis System

Considering the shortcoming in source management work for a long time, the CaiHong Group corporation propose the concep of Dynamic Consumption Norm. This has increased the enthusiasm of the workers to economize sources and reduce cost. Within a year, the corporation economizes sources for 20 billion yuan and achieves a notable effect in the work of reducing the cost and increasing the economic benefit. In order to assist the implementation of the new method in source management, both the corporation and the Education and Research Center of Plant Engineering in China have developed this 'Source Management And Analysis System '.

Tuning the face orientation of ZnO nano/microcrystals by a wet chemical method

We successfully synthesize four kinds of ZnO nano/microcrystals including dumbbell microrods, nanoflakes, nanoplates, and microrods by a simple wet chemical method. Growth duration is found to play a crucial role in the morphologies of these ZnO nano/microcrystallites. In addition, growth conditions are systematically studied as a function of precursor concentration and temperature. The structural and optical characteristics of the ZnO samples are further investigated by X-ray diffraction, scanning electron microscopy, and photoluminescence spectroscopy.

Classification method of cultivated land based on UAV visible light remote sensing

The accurate acquisition of the grain crop planting area is a necessary condition for realizing precision agriculture.UAV remote sensing has the advantages of low cost use,simple operation,real-time acquisition of remote sensor images and high ground resolution.It is difficult to separate cultivated land from other terrain by using only a single feature,making it necessary to extract cultivated land by combining various features and hierarchical classification.In this study,the UAV platform was used to collect visible light remote sensing images of farmland to monitor and extract the area information,shape information and position information of farmland.Based on the vegetation index,texture information and shape information in the visible light band,the object-oriented method was used to study the best scheme for extracting cultivated land area.After repeated experiments,it has been determined that the segmentation scale 50 and the consolidation scale 90 are the most suitable segmentation parameters.Uncultivated crops and other features are separated by using the band information and texture information.The overall accuracy of this method is 86.40%and the Kappa coefficient is 0.80.The experimental results show that the UAV visible light remote sensing data can be used to classify and extract cultivated land with high precision.However,there are some cases where the finely divided plots are misleading,so further optimization and improvement are needed.

Water Resources Operation and Management Model and Its Simulation Process Research

Based on the status quantity of water resources in Xi′an region, a commentary on many math models is given for water resources operation and management, and the visual model is provided to solve practical problems. In this model, the information for decision is visible in GIS (Geographic Information Systems) and topological figures. With object orientation methods, the objects are described in proprieties, methods, relations and time periods. The simulation process of the model is developed with Delphi and MapInfo, and the real decision scheme could be examined and practice decision process can be simulated from which. Decision analysis conducted from visual conditions is believable. The exploration to visual model is a beginning of practice research, much more study of which still needs to do.

Experimental-computational study of fibrous particle transport and deposition in a bifurcating lung model

Experiments carried out using a lung model with a single horizontal bifurcation under different steady inhalation conditions explored the orientation of depositing carbon fibers, and particle deposition frac- tions. The orientations of deposited fibers were obtained from micrographs. Specifically, the effects of the sedimentation parameter （γ）, fiber length, and flow rate on orientations were analyzed. Our results indicate that gravitational effect on deposition cannot be neglected for 0.0228 〈 γ 〈 0.247. The absolute orientation angle of depositing fibers decreased linearly with increasing y for values 0.0228 〈 γ 〈 0.15. Correspondence between Stokes numbers and y suggests these characteristics can be used to estimate fiber deposition in the lower airways. Computer simulations with sphere-equivalent diameter models for the fibers explored deposition efficiency vs. Stokes number. Using the volume-equivalent diameter model, our experimental data for the horizontal bifurcation were replicated. Results for particle deposition using a lung model with a vertical bifurcation indicate that body position also affects deposition.