Abstract: The length of the anchor chain released directly influence the holding power of anchor and holding power of anchor decides the safety of the ship in the state of anchoring. In order to calculate the length of the catenary for anchored vessel in static hydraulic condition, Parabola and catenary mathematical model has been used in this paper to the data processing. These two kinds of thoughts are both based on the infinitesimal dividing model. The parabola method is using the Taylor series expansion to calculate the results of former 3~5 terms respectively, while catenary one uses the differential solving method. Through the example analysis to compare the accuracy of results obtained by these two methods, the conclusion can be obtained that parabola method is closely related to Taylor expansion terms. For a certain range of the anchored catenary length, the more Taylor series expansion, the more accurate results we can get; the gap of the results calculated by these two methods can be neglected. The catenary method is more accurate than that of parabolic one when the length of the catenary beyond this range.
Abstract: The combustion characteristic of low calorific fuel gas was numerically investigated in porous burner by preheating air. Two-dimensional temperature profile, flame propagation precess, and CO reaction rate were analyzed detailly by preheating air, and compared with that of room air. The results showed that when the air is preheated, the combustion flame location locates to upstream, the maximum combustion temperature is higher than that of room air, and flame propagation velocity decreases.The CO oxidation reaction rate increases gradually with the radius distance increaing, but reaction region decreases. CO oxidation region guradually decreases and locates to the upstream with air preheating temperature increasing. Peaks of CO oxidation rate gradually change from two to one.
Abstract: 172 basic Cessna plane in the process of operation, the production of equipment failure is random, so the evaluation of equipment performance and to predict its failure time to improve the safe operation of the 172 basic plane has important application value. On the plane this complex system, the grey theory combined with 172 basic Cessna plane, the collection of 172 basic aircraft fault information centralized data processing, analysis, prediction model GM (1, 1), through the calculation of the GM model data, and the error precision fitting test, better realize the basic 172 aircraft equipment failure time prediction.
Abstract: In the traditional teaching process of analog circuit course, the connected circuit element and current trend are not intuitive and students understand difficultly. In order to solve this problem, the teaching aid of analog circuit based on magnetic elements is researched and designed, including a DC power supply, some element modules and some connecting soft lights, both ends of the connecting soft light has a connecting plug connection, element module is comprised of bottom plate, switch, socket, input slot, output slot, symbol and permanent magnet, input slot and output slot are communicated together , switch and symbol are communicated together, permanent magnet is located at the bottom of the component module. By a plurality of component modules absorbed on the surface of iron blackboard that are marked with the symbol to make up the teaching circuit, by shining of connecting soft lights to simulate the current in the circuit, the teaching content of analog circuit is vividly demonstrated and understanding of students for teaching content is improved.
Abstract: In this paper, a fitness device which could generate electricity was designed into rod group structure based on theoretical calculation and experiment. The device could make mechanical energy into electrical energy in process of fitness, and the storage power could used to daily life lighting and small household electrical appliances power. Physical prototype of the device was developed successfully, the actual test results show that, the safe load of the device was 100kg, the charging voltage was 5V and 12V. People could generated available energy in process of fitness, positivity of fitness for people were removed, in results, the device contained certain practical value of popularization.
Abstract: The self-inductance is the inherent phenomenon in a wire. Through the comparison of two kinds of method for solving the self-inductance, stated that note in the current contribution rate problem in the process by the first method to solve the self-inductance coefficient. Through solving the relationship between the coefficient of self-inductance and cable radial thickness for coaxial cables that cable, the coefficient of self-inductance decreases monotonously with the radial thickness of the reduction.
Abstract: With rapid development of integrated circuit technologies, power consumption has been a key factor for long time, beside speed and area. Currently, in order to obtain the optimal low power result, we try to reduce system power consumption in each stage of integrated circuit design. Base on the traditional methodologies, a dual optimization methodology is developed, which reduces not only the number of addition operations, but also the width of one multiplier. From implementation point of view, the result of first optimization can be used for the second one, such implementation save the computation effort of second optimization, and promote operation speed and efficiency of whole methodology. The dissertation develop the low power technique for multipliers in different stages, it has reference value to integrated circuit front-end low power design for fixed coefficient multipliers.
Abstract: In combination with ALU design, this paper proposes a design method based on the sharing of resources equivalent transformation. Based on the analysis of a resource-shared ALU design example, an ALU function is presented. Compared with method based on the instruction function design, the resource sharing design methods have unique advantages in terms of saving resources. The design method is not suitable for modern HDL-based design method described herein, but also to the schematic design of a conventional method.
Abstract: Study on the deterioration of the constant current remote feeding system throughout the life of the structure is always one of the most important issues in seafloor observatory network reliability engineering. Relationship between current-to-current convertor subsystem and amount of loads in branch line is described by introducing failure rate factor. Multistate reliability model of remote power feeding system has been set up and solved by genetic algorithms. Simulation results show that as the load configuration in trunk line and branch line changing, there exists best combination maximizes the system reliability, besides, appropriate increasing amount of loads in branch line can optimize the preventive strategy.
Abstract: Due to the actual situation, when carrying out research on the principle of low-voltage distributed PV power station, we should make research on the process of survey and the determination of measurement program. And the working-out process of the connection scheme to the first distributed PV power station in Liaoning region is stated. After the discussing the difficult problem on the development of the connection scheme, the next phase of research direction is proposed.