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- Abstract：A Lienard differential equation with time-delay is studied. The time delay r can qualitatively change the dynamics. Choosing time delay r as parameter, when r increases, the unique equilibrium can switch from being stable to unstable, thus Hopf bifurcation happens. The bifurcation direction is also computed by using the normal form method.Keywords：delay,Hopf bifurcation,Lienard differential equation,1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：flos lonicerae,chlorogenic acid,extraction process6|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A yield map generating system-YMapper was developed using Visual Basic 6.0 programming language. A local-averaging interpolation method with a coarse error data filter was studied. Approaches of coordinates definition, yield data classification and statistics, yield map rendering and plotting were discussed. The system was tested with yield data of winter wheat, soybean, corn, and cotton. The test result showed that the system was steady. Using the interpolation function available and useful yield maps can be generated from yield data that gathered by combine harvester yield monitoring system. The error data filter can prevent the yield data with too high or too low value from being calculated while interpolation, then the yield map accurate can be improved. The system can show how the yield distributed in the field in the form of yield data point maps or yield maps, which can be rendered and classified according to users' needs. Statistics function is also provided for yield data analysis.Keywords：precision agriculture,yield map generation,interpolation,software development0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To counter the blocking issue of no-tillage planter, a new sawtooth anti-blocking compoent was developed, and anti-blocking mechanism was investigated. The kinematics of the straw and sawtooth were analyzed, and mathematics equations of some movement parameters were set up, and main factors of effecting throwing characteristics were determined. Theory analysis and experimental results in the soil bin device showed that the sawtooth anti-blocking compoent has the better anti-blocking characteristics, and it could be put into practice as anti-blocking compoent for no-tillage planter.Keywords：no-tillage planter,sawtooth blade,anti-blocking,mechanism6|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A portable detector for soil electrical conductivity (EC) based on four-electrode measurement method was developed. The detector includes 3 parts, which are the sensor, the control and data acquisition box and the data processing software. The sensor injects stable electrical current into soil and detects the voltage drop in it. The voltage drop can be used to estimate the soil EC. The control and data acquisition box has the functions of data acquisition, calculation and communicating with a PC. The data processing software is designed to put the data from the data acquisition box into a Microsoft Access database for analysis. Laboratory test showed that the system performs well. Several nonlinear mathematical models are applied in the regression analysis, and the best result is obtained from the model of power function, in which the determined coefficient (R2) is greater than 0.99.Keywords：soil,electrical conductivity,four-electrode,precision agriculture3|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to overcome the problem of the low frequency of proliferation of garlic shoot-tips culture, the garlic bulbs and the shoot-tips (explants) with 1, 2 leaf primordiums need to be treated under low temperature. The forming and growing of the shoot of garlic shoot-tip cultures were promoted under low temperature. The effect of the treatment on explants was better than that of on bulb. During the same period of 60 days under low temperature, the number of shoots was 10 times as much as that of bulbs. In average, each shoot form 22.2 new shoots. Accumulative effects were not observed as the shoot-tips and bulbs were treated under the same low temperature. On the contrary, the effect on bulbs was weakened than that of on explants.Keywords：garlic,shoot-tip culture,explant,low temperature disposing0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：RZ-60 is a new kind of chopping and rubbing machine for crops. The processed materials are suitable for feed cattle, sheep or goat. Some parameter should be determined by experiment. This article involves the effective parts affect the intake air velocity and motor power.Keywords：corn stalk,forage cutter,hay chopper,knife,0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The method of rotation vector and software of MATLAB were used to analyze the displacement of the spatial 7R mechanism and confirm every pole and connection direction unit vector. The vectors' closed equations of the mechanism as well as every displace equations were developed and found the relation between other poles' position and the initiative input angle by transferring the function of the matrix operation and non-linear equation of MATLAB, then figured out the spatial track of any point of any pole. Drawing functions were used to express the displacement curve and any point track. The example showed that the given method is reliable.Keywords：the 7R mechanism,the method of rotation vector,MATLAB,the displacement analysis,1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：GIDC-C was designed for computer network. Fabricated with very large scale integration technology, the chip is a soc which include CPU,RSA,DES module. The top-down design methodology was adopted. The ASIC scheme and detailed structure of CPU,RSA,DES were presented. Power consumption, reliability and simulation is analyzed. The result of simulation and verification validates that the circuit works stably and reliably. The Encryption rate was reached to 5 times per second for RSA and 2?Mbit per second for DES.Keywords：CPU,SOC,encryption,0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Taking HT120 spotwelding robot made in China as an example, the effect of parallel four-bar mechanism on the reachable workspace of spotwelding robot and dynamic model of robot based the parallel four-bar mechanism were deeply analyzed. The analytical results showed that the dynamic and service performance of robot were improved by using the parallel four-bar mechanism. But only the parallel four-bar mechanism is not enough to balance in practice. So it is necessary to combine the parallel four-bar mechanism with other devices in order to keep a very good inertia balance.Keywords：parallel four-bar mechanism,spotwelding robot,reachable workspace,dynamics,inertia balance0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：On the basis of the existing electronic weight sorter controlled by PC, a new microcomputer control and measurement system was developed, which reduces the cost of the device and keeps the former system's main function. The AT89C51 microcomputer was used as its core and was provided with some correlative circuits, including a signal adjustment circuit, an A/D convert circuit, a signal output circuit and a display/keyboard unit. When it works, the system receives analog voltage signals produced by fruits from a pressure sensor, and then these signals will be amplified, filtered and converted to digital signals. After digital signals have been processed by the system software, fruits will be dynamically measured and sorted in real time. The experiment results indicated that this system works well and can be easily controlled; meanwhile it is multipurpose by setting sorting levels to sort different kinds of fruits.Keywords：microcomputer,electronic weighting,fruit sorting,control and measurement system,1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Being with taking the background of data warehouse for instance, the process of constructing the data warehouse model was discussed in detail, and a kind of data warehouse architecture containing four store-structures and three data-flows was put forward. Two new ideas was given compared with other similar systems, firstly, the second index for data warehouse was created, for the purpose of accomplishing the enterprise data integration and system query speed, which win the time at the cost of space. Secondly, the surrogate key was set in the data warehouse, which makes the integration of multiple data source simple, improves the speed of data draw-out, data conversion, data load and makes it possible for the iterative development to the data warehouse system. An advice of constructing the data warehouse model was put forward: adopting star model, merging atom data model and statistics data model, seting the surrogate key.Keywords：data warehouse,data model,data storage2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The multi-objective synthesized evaluating system was developed to solve the decision and evaluation problems of multi-objectives. The system allows the user to create the architecture model of the project branches and decides the branch weight using the level analysis and ratio analysis. The projects were evaluated using different methods, such as optimal point, priority sorting, linear weight and grading. At last, it integrates the former four ways to achieve the comprehensive result by using the Copeland way. We applied the system into various actual problems and all received impersonal and fair evaluation results. So it is proved that the system is quite a applied one.Keywords：multi-objective problem,branch weight,synthesized evaluating,3|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：It is recurred to the specialty and rule of true greenhouse by controlled component animation move and rove of virtual greenhouse.The rove,controlled component animation and the construction of enclosurings of virtual greenhouse are realized by using 3DS max,OpenGL and Panoroma Technology in VC++6.0 MFC. The simulation result showed that it is coincide with the truly greenhouse in micro-climate environment.Keywords：virtual reality,virtual greenhouse,OpenGL,controlled component animation,rove0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The visual system of automobile driving training simulator and advanced visual simulation software (Open GVS SDK and MutiGen Creator) were designed and developed. There are terrain model, two Dimension models and three Dimension models in the system. The technology of single-channel graphics display was described. The methods of multi-channels graphics display based on single-channel was presented. This system has ample scene and good visual effect, and can better fit in with the need of driving training.Keywords：visual system,modeling,channel,virtual environment2|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Dynamic water environment simulation is the key of NSBD (North to South Water Transfer Project) scene simulation. By the analyzing of the water simulation method and the need of NSBD Simulation System, this paper give a way which is based on water wave theory and Computer Graphics to develop the dynamic water environment. It is good for the dynamic water environment.Keywords：simulation,computer graphics,dynamic water environment2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：activated alumina,drinking water,fluoride ion,adsorption equilibrium,kinetics0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：hydraulic turbine runner,3D Euler method,laminar flow,numerical simulation0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The design and realization method of ATMS platform in ITS(Intelligent Transportation System) was introduced. The topology of the system was given. The structure of three layers C/S was adopted in the platform, so each part of the platform could be programming independently. The distributed application of each subsystem was realized using COM/DCOM technology that assured the communication between the subsystem. The application example showed that the work efficiency of the traffic management department has been enhanced greatly.Keywords：ITS,ATMS,design and realization0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on the analysis of present situation and the project of master planning for Changchun agricultural sci-tech district, considering of the planning objective, environmental condition, planning and building idea, function, industrial development analysis, spatial structure, function district and master layout, the thinking of master planning was developed and the main content of the comprehensive agricultural sci-tech district was put forward. The industrial development, sci-tech research, service environment was considered.Keywords：agricultural sci-tech district,master planning,thinking and content2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Value Chain is a useful tool of scaling corporation core competitive advantage. It is of great significance of thoroughly analysis the change of value chain structure and optimize it for enhancing corporation core competitive advantage. Firstly analyzing value chain meanings and structure, the goal and method of value chain optimization were discussed. Based on degree to customer value realization and resource qualifications inside, the fuzzy linear programme model of value chain optimization was set up by using the methods of dynamic cost analysis and marginal cost analysis. Finally, the calculating model and its optimal outcome were given according to the value chain of saloon car manufacture.Keywords：value chain,core competitive advantage,customer value,optimization,cost structure,1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Usually we studied the relationship of these parameters, such as security price, coupon rate, income and term by experimentation. Strictly speaking it dose not work by several special examples to account for the general conclusion. By the analysis of quantity and mathematics the relationship of these parameters was developed in detail and some valuable results about the relationship of these parameters were obtained.Keywords：security price,coupon rate,income rate,0|9|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The Comparative Advantage Index of yield per unit area, Scale Comparative Advantage Index and Comprehensive Comparative Advantage Index of the major crops in Pingdingshan region were calculated and analyzed. The result showed that the corn, potato and tobacco produced in Pingdingshan region have distinct comparative advantage comparing with those produced in Henan province. Compared with the wheat, corn, potato, peanut, sesame and tobacco produced in China, the crops produced in Pingdingshan region also have obvious comparative advantage. At last, the suggestions on how to adjust the structure of the crops were put forward.Keywords：comparative advantage index of yield per unit area,scale comparative advantage index,comprehensive comparative advantage index,major crops4|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on the advantage of comparison, the relationship between industrialized agriculture technologies and other production essentials was analyzed. The authors bring forward the idea that the technologies of agricultural facilities environment for certain cultivars and manufacture technologies are no longer the major obstacle in improving the benefits of industrialized agriculture in China; the direction of technology is to originally develop the seeds and seedlings and the post-harvest processing technologies which can increase the yield and labor force usage; other technologies should be developed around the cultivars with intenational competence based on China's particularity; the need of automation that will take the place of labor is weak in China, therefore, it should be developed carefully as a long term technologies repertory.Keywords：industrialized agriculture,technologies,produce factor,comparative advantage0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
