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At present, the most common method of collecting traffic conflict data was the site observation method. Data processing methods were mainly manually observed by site or video. To overcome the shortcomings of traditional data collection and processing methods, video recognition was collected by UAV (Unmanned Aerial Vehicle) flying at high altitude and conflict were automatically detect by video recognition software in this paper. Compared with traditional data collection methods, UAV has a good high-altitude field of view, does not have shooting angle and occlusion problems, and has a large shooting range, which has obvious advantages. The video recognition program consists of the following parts: image reading and calibration, vehicle identification, vehicle tracking. Video recognition got continuous high-precision vehicle trajectory data, subsequent processing to obtain continuous vehicle conflict data. Finally, we can use these data to evaluate road traffic safety. The results show that this method can effectively evaluate road traffic safety.

This paper presents a novel approach to design non-minimum phase (NMP) dynamic control systems, which consists of two stages of design. Specify a desired minimum phase (MP) plant model, with desired zeros and the same orders as original plants and then determine a hauling polynomial (by resolving the difference between the specified MP zeros and underlying NMP zeros) to convert a NMP control system design into MP formality. The second stage is to design an invariant closed loop system, then find the controller output by resolving an inverse dynamic in form of U-model root solving. To demonstrate the design procedure and potential for applications, take Boeing 747 altitude-hold autopilot for bench test. For comparison, Linear Quadratic Gaussian (LQG) design is selected which is a very classical approach. Simulation results illustrate the effectiveness and efficiency of the proposed control scheme.

As a universal framework, U-model has established an enabling design prototype for the control of non-linear dynamic plants with concise and applicable linear approaches. This study is devoted to a remaining fundamental research question, that is, while U-model methodology is applied to a linear dynamic plant control system design, how different it is from classical linear approaches. Taking up an initial research, this comparative study uses pole placement controller design as an example to implement with two approaches in terms of U-Model based design and classical control design. Design efficiency and effectiveness are compared analytically and computationally via numerical experiment, which justifies the superiority of U-model in designing linear control systems (or at least in designing pole placement control). In addition, the study provides benchmark examples for users with their ad hoc applications.

In this study, a new U-PPC-Type II (U-model Pole Placement Control Type II) control system design procedure is proposed based on the U-model principle. The objective of a U-PPC-Type II design is to determine a linear controller G c from a specified closed loop linear transfer function G cls . The study also compares the new design procedure with a U-PPC-Type I based design procedure. For demonstration of the effectiveness of the proposed new procedure, U-PPC-Type II is designed for both a linear dynamic model and a Hammerstein (nonlinear dynamic) model. The simulation results are presented with discussions and graphical illustrations.

ISS (Instruction Set Simulator) plays an important role in pre-silicon software development for ASIP. However, the speed of traditional simulation is too slow to effectively support full-scale software development. In this paper, we propose a hybrid simulation framework which further improves the previous simulation methods by aggressively utilizing the host machine resources. The utilization is achieved by categorizing instructions of ASIP application into two types, namely custom and basic instructions, via binary instrumentation. Then in a way of hybrid simulation, only custom instructions are simulated on the ISS and basic instructions are executed fast and natively on the host machine. We implement this framework for an industrial ASIP to validate our approach. Experimental results show that when the implemented ISS, namely GS-Sim, is applied to practical multimedia decoders, an average simulation speed up to 1058.5MIPS can be achieved, which is 34.7 times of the state-of-art dynamic binary translation simulator and is the fastest to the best of our knowledge.

Dynamic binary instrumentation tools play a very important role in program analysis. The information gathered by these tools is quite useful in software development, testing, debugging, simulation and optimization. SEntre is such an instrumentation system with the features of efficiency, ease-to-use interface, transparency and comprehensiveness. To obtain good performance, we employ instrumentation while copying (IWC) mechanism. The interface provided by SEntre is very simple but powerful. User can develop different tools based on SEntre. To illustrate SEntre's versatility, we describe two tools, one is used to obtain memory access address and the other is an extremely fast simulator.

This paper presents an Application Specific Instruction Set Processor (ASIP) pruned for high-throughput and variable-length Fast Fourier Transform (FFT), which is a key component of various Orthogonal Frequency Division Multiplexing (OFDM)-based wireless communication standards. The ASIP executes dedicated FFT instructions to process two radix-4 or four radix-2 butterfly operations every clock cycle. Furthermore, a shuffle-embedded register file and a programmable memory access coprocessor are employed to tackle the memory access bottleneck and reduce power consumption. The implementation results show that our ASIP requires only 892 clock cycles for a 1024-point FFT, which outperforms TI TMS320C64x DSP and Tensilica ConnX ASIP by 6.74X and 2.03X, respectively. A test chip of the proposed ASIP was fabricated using CMOS 65nm process with the core area of 1.9mm2. It consumes 85mW when it runs at the maximum frequency of 150MHz.

At present, the results of mine geological environment investigation are often expressed by 2D Maps, but 3D-Visualization technology will make these results more directly perceived through the senses. In the existing theories and technology conditions and aiming at the characteristics of mine geological environment, this paper solve the problem of unified visual of Terrain model, Surface features model, and underground model. Also, when builds the special features of geological environment models, it uses DEM grid data. This way makes its model more accurate image. At the end, this paper builds a 3D Xikuangshan geological environment modeling successfully by ArcScene software.

The installed direction and angle of Solar Collector is very important to the solar water heater's efficiency. This paper is based on the formula of total amount of solar radiation on inclined plane and the law of apparent motion of sun. It gets the optimal direction and angle of solar collector by calculation and analysis. By using computer achieved this algorithm and analysis these results, this paper get the law of optimal direction and angle in different latitude and different seasons. It provides the foundation of the solar water heater's direction and angle, and updates the exiting standards by its results.

With the development of digital information technology in mining industry, Digital Mine plays an important role in the process of mine construction. The current situation is that mine management information system is usually based on one certain technology platform. Due to the diversity of mine tasks and the inability of a single technology platform to manage multiple data types, people are focusing on the integration of multiple platforms. We designed the mine management information system to be based on GIS, Surpac, TCL and.net. Heterogeneous data are managed, processed, queried effectively in the system. At the same time, the statistical analysis, 3D modeling and estimate reserve can be achieved. In this paper we introduce the methods and thought to design mine management information system and the way to manage heterogeneous data, we discuss the design and development of mine management system based on GIS, Surpac, TCL and .net.

Mountain Torrents has characters of suddenness, supervised disaster and other prominent features of destructive. This paper, focused on the characteristics of flood disasters, discussed the way to design Mountain Torrents Early Warning System, which is based on WebGIS. Firstly, we analysis current condition of research and introduce the requirements. Secondly, We discuss the system structure and database design. At last, we state the key technology of the system. It turns out that it realizes real-time monitoring of flood disaster warning and forecasting capabilities.

In allusion to the geographical phenomena or processes whose mechanism or theory is not clear, GIS-Based logical information method adopts normal theory of logical information method, and actualizes logical distinguishing among correlative geographical factors about research object by using spatial classification and spatial analysis of GIS, and integrates statistical method then realizes logical information method upon geographical model. First of all, in allusion to regional and spatio-temporal characters of SARS (Severe Acute Respiratory Syndrome) epidemic in 2003, the environmental factors which can affect the epidemic of SARS are filtered, confirmed, and distinguished by using GIS technology and mathematical method. Secondly, the analysis of dependence relation and classification of dependence extent about environmental factors of SARS epidemic are carried out. Thirdly, the diacritical weighting for each dependence factor and object weighting for each region are calculated. At last, the grade of epidemic situation for each region are evaluated and forecasted.