DETECTION OF TRAFFIC DENSITY WITH IMAGE PROCESSING USING PIN HOLE ALGORITHM

The intelligent traffic monitors are devloped and became more interst in recent years. A detection system in the monitoring traffic system is proposed using different algorithms. Pin Hole Algorithm used to detect the car that passes the road (the studied area). A fixed camera mounted at predetermined point used with known height (of the camera), the intensity of the light, and the visibility of the camera. The classification process is important to know the traffic congestion status. The traffic congestion status will be sent to the server address already provided. In the congestion detection test results were obtained with an accuracy value of 85% using the 64x64 grid division and obtaining good detection results for susceptible light intensity values between 5430 and 41379 LUX with an accuracy value of between 60% and 90%. ABSTRAK: Sejak beberapa tahun ini, sistem pengawasan trafik pintar telah dibina dan terus berkembang luas. Sistem pengesanan dalam sistem trafik pengawasan telah dicadangkan menggunakan pelbagai algoritma. Algoritma lubang pin digunakan bagi mengesan kereta yang melalui jalan (kawasan kajian). Kamera dipasang tetap pada titik tertentu iaitu dengan menyelaras ketinggian kamera, keamatan cahaya, dan kebolehlihatan kamera. Proses klasifikasi sangat penting bagi menentukan status kesesakan trafik. Status kesesakan trafik akan dihantar ke alamat pelayan yang telah disediakan. Nilai ketepatan ujian pengesanan kesesakan yang diperoleh adalah 85% iaitu menggunakan pembahagi grid 64x64 dan dapatan kajian menunjukkan pengesanan yang baik bagi nilai keamatan cahaya antara 5430 dan 41379 LUX dengan nilai ketepatan antara 60% dan 90%.

Study on the influence of structure shape of semi armour piercing warhead on vertical armour piercing efficiency

In order to evaluate the impact of different warhead shapes on the damage efficiency of semi armour piercing warhead effectively, four common semi armour piercing warhead models are established based on Solidworks, and the deck model is established with reference to the deck data of an aircraft carrier. And then the material setting and grid division are carried out based on Ansys so as to construct the explicit dynamic simulation model. The credibility of the model is verified based on the residual velocity theory after the model being established. Finally, based on the established model, the simulation research on the influence of warhead shape on vertical armour piercing ability is carried out. The results show that under the same velocity, the armour piercing ability of sharp oval and conical warheads are better and their residual velocity are higher.

ASYMPTOTIC METHODS OF ANALYSIS IN ELECTRODYNAMICS

Рассматривается метод геометрической дифракции и физической оптики, который является одним из самых точных и эффективных для решения крупных электродинамических задач. Для анализа характеристик процесса приводится его математическое описание, а также для сравнения с ним приведено описание метода конечного интегрирования, который является наиболее популярным и эффективным для малых объектов. Так показано, что применение метода МКИ невозможно для крупных объектов, так как в процессе сеточного разбиения происходит создание слишком большого числа ячеек для расчета, что значительно усложняет процедуру анализа. Для оценки эффективности и точности метода было произведено моделирование антенного элемента, который установлен на корабле-носителе. Так, характеристики излучателя рассчитывались с использованием метода конечного интегрирования, после чего характеристики диаграмм направленности передавались в проект с кораблем, затем производилось моделирование с использованием метода SBR. Итоговые результаты моделирования показали высокую эффективность и точность метода, а возможность установки шага сканирования позволяет управлять временем моделирования, однако стоит учитывать, что слишком большой шаг приводит к снижению точности анализа The article discusses the method of geometric diffraction and physical optics, which is one of the most accurate and effective for solving large electrodynamic problems. To analyze the characteristics of the process, we give its mathematical description and, for comparison, a description of the final integration method, which is the most popular and effective for small objects. Thus, we show that the application of the MCI method is impossible for large objects since in the process of grid division, too many cells are created for the calculation, which significantly complicates the analysis procedure. To assess the effectiveness and accuracy of the method, we simulated the antenna element, which is installed on the carrier ship. We calculated the characteristics of the emitter using the method of finite integration, after which we transferred the characteristics of the radiation patterns to the project with the ship, then we carried out the simulation using the SBR method. The final results of modeling showed high efficiency and accuracy of the method, and the ability to set the scanning step allows you to control the simulation time, however, it should be borne in mind that too large a step leads to a decrease in the accuracy of the analysis.

Research on Collision Detection Method of Contact On-line Measurement

In order to avoid collision and improve the safety of on-line measurement, a contact on-line measurement collision detection method is studied. Firstly, according to the structural characteristics of the probe and workpiece, the dynamic collision detection between the probe and workpiece is transformed into static collision detection by using the discrete method, and then the grid division of the collision detection space is carried out by using the space division method. Finally, the dynamic collision detection between the probe and workpiece is transformed into the intersection judgment between simple geometry, and according to different collision accuracy requirements, Hierarchical collision detection combining rough detection and fine detection is carried out. Experimental results show that the hierarchical collision detection algorithm has high detection speed and accuracy.

Research on Matching Characteristics of Wind Turbine and Generator for Small H-shaped Vertical Axis Wind Turbine

Based on the small H-shaped vertical axis wind wheel model (NACA0016), a CFD wind wheel model was constructed. Based on the principle of moving grid, the grid division of the CFD wind wheel model is completed by using GAMBIT software, and the boundary conditions such as the inlet boundary and the outlet boundary are set reasonably. Then, the turbulence model and the couple algorithm are used to carry out transient simulation calculations, and finally the aerodynamic parameter curves of the two-dimensional CFD wind wheel model are obtained. Based on this, the matching characteristics of the wind turbine and generator of the small H-shaped vertical axis wind turbine are studied. The research results show as follows: when the incoming wind speeds change in range of (2 m/s, 12 m/s), and the power characteristic curve and torque characteristic curve of the generator wind wheel are respectively overlap the best power curve and best torque of the generator, the matching characteristics of the small H-shaped vertical axis wind turbine rotor and generator are optimal, which provides reference for carrying out related research.

Location Privacy Protection Scheme for LBS in IoT

The widespread use of Internet of Things (IoT) technology has promoted location-based service (LBS) applications. Users can enjoy various conveniences brought by LBS by providing location information to LBS. However, it also brings potential privacy threats to location information. Location data that contains private information is often transmitted among IoT networks in LBS, and such privacy information should be protected. In order to solve the problem of location privacy leakage in LBS, a location privacy protection scheme based on k -anonymity is proposed in this paper, in which the Geohash coding model and Voronoi graph are used as grid division principles. We adopt the client-server-to-user (CS2U) model to protect the user’s location data on the client side and the server side, respectively. On the client side, the Geohash algorithm is proposed, which converts the user’s location coordinates into a Geohash code of the corresponding length. On the server side, the Geohash code generated by the user is inserted into the prefix tree, the prefix tree is used to find the nearest neighbors according to the characteristics of the coded similar prefixes, and the Voronoi diagram is used to divide the area units to complete the pruning. Then, using the Geohash coding model and the Voronoi diagram grid division principle, the G-V anonymity algorithm is proposed to find k neighbors in an anonymous area so that the user’s location data meets the k -anonymity requirement in the area unit, thereby achieving anonymity protection of location privacy. Theoretical analysis and experimental results show that our method is effective in terms of privacy and data quality while reducing the time of data anonymity.

Geometrically Invariant NSCT–GPCET-Based Image Watermarking with Accurate Moment Calculation

Generic polar complex exponential transform (GPCET), as continuous orthogonal moment, has the advantages of computational simplicity, numerical stability, and resistance to geometric transforms, which make it suitable for watermarking. However, errors in kernel function discretization can degrade these advantages. To maximize the GPCET utilization in robust watermarking, this paper proposes a secondary grid-division (SGD)-based moment calculation method that divides each grid corresponding to one pixel into nonoverlapping subgrids and increases the number of sampling points. Using the accurate moment calculation method, a nonsubsampled contourlet transform (NSCT)–GPCET-based watermarking scheme with resistance to image processing and geometrical attacks is proposed. In this scheme, the accurate moment calculation can reduce the numerical error and geometrical error of the traditional methods, which is verified by an image reconstruction comparison. Additionally, NSCT and accurate GPCET are utilized to achieve watermark stability. Subsequent experiments test the proposed watermarking scheme for its invisibility and robustness, and verify that the robustness of the proposed scheme outperforms that of other schemes when its level of invisibility is significantly higher.

A New Challenge: Detection of Small-Scale Falling Rocks on Transportation Roads in Open-Pit Mines

In transportation at open-pit mines, rocks dropped as a mining truck is driven will wear out the tires of the vehicle, thus increasing the mining cost. In the case of autonomous vehicles, the vehicle must automatically detect rocks on the transportation roads during the driving process. This will be a new challenge: rough road, rocks of small size and irregular shape, long detection distance, etc. This paper presents a detection method based on light detection and ranging (lidar). It includes two stages: (1) using the modified cloth simulation method to filter out the ground points; (2) using the regional growth method based on grid division to cluster non-ground points. Experimental results show that the method can detect rocks with a size of 20–30 cm at a distance of 40 m in front of the vehicle, and it takes only 0.3 s on an ordinary personal computer (PC). This method is easy to understand, and it has fewer parameters to be adjusted. Therefore, it is a better method for detecting small, irregular obstacles on a low-speed, unstructured and rough road.