Papers by Keyword: Digital System

Abstract: The purpose of this study is to achieve chromatic aberration, color appearance attribute value fast computing; and observe conditions in different color appearance of digital image conversion between digital color appearance evaluation system. Digital color appearance evaluation system through analysis showed that the final form that can be color difference calculation, calculation of color appearance attributes forward and reverse computing, digital image conversion, to obtain a digital image tristimulus values, color point color display and so on.

Abstract: Based on the digital serial communication, E1 and Ethernet port circuits connecting the electronic equipment on ships, characterizations of the digital signals transmitted through the circuits are analyzed. The situations when the EMI generated by the digital systems causing pollution to the grounding system and the grounding voltages coupled to the signal-transmitting circuits are simulated. Furthermore, the influence of the equivalent impedance of the main and branch grounding cables on the grounding performance are analyzed quantitatively. Therefore, the grounding demand is obtained. Finally, some anti-interference measures so as to improve the grounding performance are proposed.

Abstract: The hierarchy design method of digital system based on EDA is proposed through the design of digital frequency meter system in this paper. Firstly, it divides the frequency meter into different function module and Writes VHDL code to describe each module circuit. Then, it creates the schematic diagram of top circuit. Design input, compiled, logic synthesize and function simulation are accomplished use MAX+PLUS II. In the end, digital frequency meter is implemented in CPLD. The results show that the design method can greatly simplify the complexity of hardware circuit structure. Its characteristic is high reliability and strong flexibility.

Abstract: Ejection style of mold effects significantly the quality and efficiency of mold production. A new leverstyle secondary ejection mechanism is illustrated. The mechanism can solve the problem that plastic parts are difficult to eject fully after the first ejection. The mechanism has simple structure and high safety and reliability, satisfies the requirement of full automation and is suit to large quantity of mold production. Commercial CAD/CAM systems provide semi-automatic tools to assist the designer in the dimensioning process. Using the method, good results have been obtained for several basic geometric models.

Abstract: Commercial CAD/CAM systems provide semi-automatic tools to assist the designer in the dimensioning process. Analytical solutions to injection molding problems are very rare due to thecomplexities of the governing equations, the material behavior and the cavity geometry. Study of window frame fabrication by injection moulding process was carried out with the aid of Moldflow® software. Ejector plate designs were created to compare the pros and cons of each design. The investigations were carried out on flowing, packing, cooling and costing of injection moulded window frame. Using the method, good results have been obtained for several basic geometric models.

Abstract: At present, because of the extensive production management and backward information management, the coal mine enterprises require a shift to intensive management. The establishment operation management of digital system of coal enterprises can help the enterprise to realize the digital management, improve the market competition ability, promote the enterprise strategic management ability. The realization of this system can help to solve the main problems such as the difficulties of business process management and summary, unable to effectively control the business process, lack of process and cooperation difficult, difficult of business analysis. Therefore the establishment of operation management of digital system of coal enterprises becomes a pressing matter of the moment.

Abstract: To meet the requirements of the testing for modern complex digital systems and devices, A novel method for the design of digital system fault diagnosis instrument based on VXI bus is described in this paper, and the composition and design principle of the hardware of the presented method is introduced in the paper. The instrument designed with the novel method provides 64 pins of Transistor-Transistor Logic (TTL) digital I/O for the test of digital modules and systems. Testing can be automatic accomplished by programming a sequence of test vectors. Real-time data comparison ensures fast test execution by eliminating the post processing of test data. Branching and test execution pause enhance the ability to synchronize the test system to activity of the unit under test (UUT). The experimental results show the module designed with the presented method has much more higher performance than the only similar manufacture VX4820.

Abstract: According to the development of domestic and foreign Intelligent Railway, we integrate the needs of the mine railway system users, analyze internal data flow of the system, combine with the integration of the basic ideas and methodology, and use the model theory approach of model theory and system integration model. And then, we put forward mine railway intelligent transport digitizing systems integration model and design the overall framework of the mine railway intelligent transportation digitizing system

Abstract: A bit full adder is a very important component in the digital system. Design of a full-adder circuit, as an example, by changing its output function expression in the form of expression, use the gates, decoder, multiplexer etc 74 series devices, the eight circuits realization form are given respectively, and briefly analyzed the advantages and disadvantages of the various circuit implementation. The example show that the design of combinational logic circuits has mobility and variety, it could give the instructiveness and the guiding for other design of combinational logic circuits.

Abstract: In general hardware designers design integrated circuit with hardware description languages or schematic diagram. However the growth of circuit complexity makes circuit design error prone and time consuming. The resulting descriptions tend to be lengthy and hard to reason about. Therefore functional simulation, timing simulation and in-circuit test are three essential steps to ensure that the designed circuit is correct. This paper presents a method of in-circuit verification on FPGA using UART communication between the computer and the FPGA board. Through UART, designers can convert the parallel input vector into a set of serial stimulus signals and send them to the FPGA board, and also can receive the feedback serial signals from the FPGA board and reconvert them into a parallel output vector. Given the input and output ports of the verified circuit component, a verification platform based on UART communication will be customized automatically by the in-circuit verification platform generator. This breaks the constraint of the FPGA board's limited pins and supports wide-scale input/output vectors and can be applied in in-circuit test of digital circuit.