Papers by Keyword: Level

Abstract: At present, pruning of fruit trees on hills is mainly completed by climbing on trees or ladder, which could cause injury due to poor landform. In order to avoid such kind of risks, it is important to develop a lifting platform for orchards in hilly area. In this paper its structure and working mechanism were introduced. This lifting platform, as a machine, is comprised of power device, elevating mechanism, leveling mechanism, slewing mechanism, supporting mechanism and hydraulic control system, and is driven by a small four-wheel tractor. Its hydraulic system can control hydraulic cylinders to extend and retract so as to lift, lower, rotate or keep platform at horizontal position. By analyzing the machine’s kinematic model, the mode of hydrostatic triangle leveling was determined. In order to simplify the machine’s structure, a cantilever beam was used as a supporting mechanism. After carried out the performance test for the machine, the results show that the machine has the following features: stable working performance, the maximum load up to 150 kg, the lifting height 1.5 m, the rotating speed 1 r/min, the lifting velocity 0.1 m/s, and leveling error in lifting process no more than 2° (no matter on horizontal plane or on slopes). So the machine can be suitable for sloped terrain, and the design requirements are well satisfied.

Abstract: In order to effectively control the main parameters of the condenser, the lumped parameter mathematic model of a small marine condenser is presented according to its structure and working principle. The integrated control system of the condenser is designed. Matlab/Simulink software is used for the simulation of the control system. Different operating conditions of the condenser are calculated. Result shows that the integrated control system of the condenser could effectively keep such controlled parameters as vacuum, condensate subcooling degree and water level at the set value. It has guiding significance for control system design of the marine condenser.

Abstract: With the increasing attention of textile, the wear resistance of the fabric is more and more important today. The wear resistance is judged by the sample and standard sample according to sensory contrast complete, but this approach has repeated poor consistency. The subjective factors of testers influence the result heavily. So the powerful image processing tools of MATLAB was used in the analysis of fabrics image processing. By image read, display and interception, image preprocessing, and feature extraction value, the eigenvalues of total area of the hair bulb, maximum area of the hair bulb, and hair bulb number were obtained. After the improved minimum distance discrimination method was used to determine the level of wear resistance by computer. Tests show that fabrics wear resistance level can be judged quickly, accurately and automatically.

Abstract: Aimed problem A of CUMCM in 2010,use geometry method to study height and volume relation in oil tank with changed position. Get function , which was proved to be correct and reliable with numerical method.

Abstract: Sheet forming is a high-volume fabrication method for producing lightweight materials components. An important goal in manufacturing research is to determine the optimum method for producing products with less cost. In this paper, combined with the orthogonal test method and finite element method (FEM) simulation, the analysis was carried out to analyze the key process factors such as stamping force, fillet radius, and friction coefficient. Using orthogonal test method can reduce the testing time, learn how the molding parameters influence the total equivalent plastic strain, acquire the best match forming parameters, and give guidance for the better condition

Abstract: Glass lens molding is a high-volume fabrication method for producing optical components. In this paper, combined with the orthogonal test method and finite element method (FEM) simulation, the coupled thermo-mechanical analysis was carried out to analyze the key process factors. In order to reduce the testing time, an orthogonal test with three sets of level factors and three parameters is conducted to obtain the optimal molding process parameters. The result shows that the most significant parameter is molding velocity, the other effect parameters are molding temperature and friction coefficient. According to the previous analysis of orthogonal experiment, it is shown that the best optimal finishing process parameters were A2B1C1.

Abstract: The ways to gain better quality and higher casting performance is an urgent topic among aluminium producers today. This issue is also often on the agenda at conferences like this and the subjects and technologies to achieve this varies. Controlling the molten metal flow by maintaining predefined levels or level patterns is one of many powerful tools to reach this goal. Precimeter Control specializes in applications for non-ferrous molten metal level measurement and molten metal flow control. By integration, or retrofitting, any new or existing casting line can easily be automatically controlled and gain improved casting performance in a cost efficient way. This paper will focus on the main benefits from automatic level control and how some plants have achieved improvements in their casting process of DC (Direct Chill) slab (or rolling ingot) casting after implementing such technology.

Abstract: A railway is a strip-shaped corridor usually divided into multiple sections that are constructed separately. Associated construction contracts must consider scheduling. Because a railway is a continual linear structure, high-precision level surveys are needed for rail sections to connect smoothly. However, the different phases and sections of construction require multiple-level surveys, which often lead to bias in the benchmarks. Since the railway is a continuous alignment, and an inconsistent elevation system affects the civil work and subsequent track laying. This study therefore used a statistical method to eliminate inconsistencies in benchmarks. Statistics are widely used in engineering and in daily life, to solve decision making problems involving uncertainties. This study used the expected value of closing error between benchmarks as an index for recalculating level, and used the standard error of expected value as the accuracy index. Application of the proposed method using measurement data for a Taipei underground project of the Taiwan Railway Administration showed that it eliminates bias in benchmarks and provides the required accuracy for closure between adjacent points.

Abstract: Transparent and conductive ITO thin films were prepared on quartz glasses by the sol-gel dip-coating method. This process is affected by factors such as doping level of tin, number of dip-coatings (layers or thickness of film), withdrawal speed, annealing temperature and time. The effects of each factor at 5 levels on the properties of ITO films has been studied and optimized using the method of orthogonal experiments (L₂₅(5)⁵). Quantitative analysis of the parameters in the orthogonal array design was performed and the results indicate that when the sheet resistance and transmittance are the two targets, the optimum experimental conditions are: mol ratio of Sn: In: 1/10, number of dip-coatings: 8, withdrawal speed: 200 mm/min, annealing temperature: 550°C and time: 70 minutes. To validate the project, another experiment was performed under the above conditions to determine the best performance of ITO film. The test results show that the sheet resistance is 125Ω/γ and transmittance is 86.2%, which meets the expected aim.

Abstract: An idea of a control system architecture for a new wheeled mobile robot is proposed. The robot construction is characterized by an original drive mechanism and constitutes an extension of the previous research performed in Hochschule Ravensburg-Weingarten. In the new construction, the robot is given the ability to rise or lower its chassis. No complicated additional hardware is required as the level of the chassis can be changed by means of torque differences on the wheels. A modular approach is adopted to develop a hierarchical two-level and layered control system. Low and high levels correspond to local and global vehicle control. The low level is described in more detail, defining the layers and providing appropriate justification.