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A module similarity measure method of the mechanical and electrical products is studied in this paper. First this paper proposes the module assembly type coding method and network modeling method, and establishes its weighted network model by taking typical module as an example; then it studies the assembly relationship similarity, node similarity and network similarity; finally it provides the module similarity measure method based on the assembly relationship.

The paper took a structure improvement of a coupling component for board-level photoelectric interconnection and analyzed its coupling efficiency by stimulation. Firstly, it briefly introduced the commonly used coupling components, analyzed the coupling performance, and selected a coupling component to improve its structure. Secondly, it introduced methods to improve coupling components, such as 45-degree gold-plated cross section, and manufacturing ball lens on both the top and the bottom to increase the coupling efficiency of coupling components. Finally, the optical simulation software Advanced Systems Analysis Program was applied to analyze the coupling efficiency. The coupling efficiency of improved coupling component was increased. The analyses and results are significant in engineering application and guiding.

In this paper, PLCC lead free solder joint’s thermal fatigue lifetime is analyzed by using the Response Surface Methodology, combined with solder joint’s shape prediction and finite element simulation. Three key solder joint’s process parameters, pad length, gap height and solder paste’s volume are chosen to build an orthogonal array , 25 PLCC lead free SAC305 solder joint’s models with different parameters combination are built in Surface Evolver to predict the solder joint’s shape. Then the PLCC device’s surface shape models in Surface Evolver are converted to three-dimensional finite element models by using a special method. Thermal analyses give the distribution and the change of thermal stress and strain, which show the dangerous solder joint in the whole PLCC device and position with weak thermal reliability in single solder joint. Furthermore, the PLCC solder joints’ thermal fatigue lifetime are calculated with the modified Coffin-Manson equation, and the series of thermal fatigue lifetime data are processed by the Response Surface Methodology. Regression equation between thermal fatigue lifetime and the three key factors is concluded. With the solder joint’s influencing rule on thermal fatigue lifetime and the solder joint’s process parameter combination belong to the highest thermal fatigue lifetime, assembly process of PLCC is improved and then enhance the PLCC solder joint’s reliability.

Solder joint shape refers to geometry that molten solder can be achieved with spreading and wetting along the metal surface in the junction between components solder pins and printed circuit board (PCB) pad, to the metal surface contact angle and solder fillet shape[1]. BLP (Bottom Leaded Plastic) [2] which is not a type of thin out-line surface mount device(SMD) without the side lead is widely used in manufacturing of new generation memory such as SDRAM \ RDRAM \ DDR. For this non-lead SMD, the shape and reliability of solder joint is the focus of the study. In this paper, we select the C-BLP of 28-pin device as the research object, complete the forming model of solder joint shape based on minimum energy principle and the solder joint shape theory by using Surface Evolver software, and analyze two critical process parameters (solder volume and solder pad width ) impacting on the solder joint shape. The study results show that the solder volume and pad width have a significant impact on the three-dimensional shape of BLP solder joint. The law of which is that: in the case of the other fixed parameters, as the increase of the solder volume, solder joint surface gradually changes from the relatively flat to the convex, solder joint gradually changes from the completely soldered to the partly soldered in the pad connections, and solder joint heights are gradually decreased; in the case of the other fixed parameters, as the increase of the pad in width, the solder joint surface gradually changes from the convex to the flat, solder joint gradually changes from the completely soldered to the partly soldered in the pad connections, and solder joint heights are gradually decreased. The actual solder joint shape designs of BLP devices can be instructed based on predicted results.

In this paper, taking workshop scheduling of SMT product manufacture system for object, the conception of resource cost is incorporated with Petri Nets. The workshop scheduling model of SMT product manufacture system is build based on transition timed Petri Nets (TC-TPN). ω1 proportion of processing cost, ω2 proportion of processing time, ω3 mutation factor are chosen as the key factors using the improved heuristic A* scheduling algorithm. The result shows that: considering the processing time preference, when ω1=0.7, ω2=0.2, ω3 =0.1, the processing time is reduced by 5.83%, 3.45%, the processing time is decreased by 6.14% and 2.94%; however, considering the processing cost preference, when ω1=0.1, ω2=0.8, ω3 =0.1, the processing time is reduced by 1.94%, 0.86%, the processing time is decreased by 8.06% and 7.52%.

In the thermal design of embedded high-power chips microwave modules, structural parameter is one of the main reasons affect the thermal resistance, thus influences the reliability of the modules, the structural parameter optimized of the microwave components was studied in this paper. The goal of this work is to decrease the temperature and achieves the best structural dimensions. Using the ANSYS software build the EPCM module, through simulation analysis, Linear regression equation be fitted by RSM, which concerning the module maximum temperature with board area, substrate thickness, molybdenum thickness and encapsulation thickness. Based on genetic algorithms, structural parameter optimization algorithm of thermal model was proposed and the optimization structural parameter of embedded high-power chips microwave modules was achieved by corresponding optimization program. Based on ANSYS work, before optimization the model of maximum temperature is 86.717℃, the maximum temperature module of the optimization structural parameter is lower 1.28℃ than before, so the thermal resistance decreased. The result show that the maximum temperature module of the optimization structural parameter is in good accord with the FEA results. It turns out that the RSM –GA approach proposed in this work can be effective and robust in providing structural parameter optimization in EPCM.

In the thermal design of Embedded Power Chip Microwave Modules, the placement of chips on substrate has a significant effect on internal temperature field, thus, influence the reliability of the modules. In this paper, Based on BP-GA, the optimization for chips placement of EPCM is achieved by corresponding optimization program. To demonstrate the effectiveness of the results, ANSYS, finite element analysis (FEA) is carried out to assess the thermal field distribution of the optimization for chips placement. The result shows that the thermal field distributions of the optimization are consistent with the FEA results. The internal highest temperature of the initial placements is 90.369℃. After optimization, the internal highest temperature is 86.128℃, the highest temperature be reduced more than 5℃. It can effectively deal with the problem about optimize the thermal placement of EPCM chips, and improves the internal thermal distribution.

The effect of loss of transmission line on the transmission signal can’t be ignored in microwave circuits. Based on the theory of loss and microwave network principle, the effect of the width, parallel length and space of transmission lines on the scattering parameters’ insertion loss is analyzed in perspective of scattering parameters of the odd mode and even mode. The simulation results show that: when the other parameters are fixed, both the characteristic impedance and the conductor loss decrease non-linearly with the line width broadening; due to the coupling effect between micro-strip lines, the first trough frequency of the scattering parameter S21 curved line, that is the point the signal energy attenuate most seriously, decreases linearly with line width broadening and increases non- linearly with line spaces broadening.

We present an approach to recognizing characters in surface mount technology (SMT) product. An improved SMT product character recognition method is proposed which can obtain a good recognition rate. Some appropriate image processing algorithms, such as Gray processing, Low-pass Filter, Median Filter, and so on, are used to eliminate the noise. Then, Character image is obtained after character segmentation and character normalization. Finally, a three-layer back propagation (BP) neural network module is constructed. In order to improve the convergence rate of the network and avoid oscillation and divergence, the BP algorithm with momentum item is used. As a result, the SMT product character recognition system is developed. Experimental results indicate that the proposed character recognition can obtain satisfactory character-recognition rate and the recognition rate reached over by 98.6% when the hidden layer of BP neural network module has 20 nodes.

Three compounds were isolated from the tissue culture cells of Daphne giraldii cullus, their structures were identified as daphneolone (1), S-(+)-1-(4-hydroxy-3-methoxyphenyl)-3-hydroxy-5-phenyl-1-pentanone (2), S-(+)-1-(4-methoxyphenyl)-3-hydroxy-5-phenyl-1-pentanone (3), and among them, 2 was a new compound, 3 was a novel natural product.

Chemical investigation of Syringa velutina Kom. led to the isolation of two new secoiridoid glucosides. Their structures were identified as 6′-O-(6, 7-dihyrofoliamenthoyl)-8-epi-kingisidic acid (syrveoside A, 1) and 6′-O-menthiafoloyl-8-epi-kingisidic acid (syrveoside B, 2) on the basis of chemical and physicochemical evidence.

A new compound, 3,6,20(S)-trihydroxy-12,23-epoxydammar-24-ene,6,20-di-O-β-d-glucopyranoside (1), was isolated from the leaves of Panax ginseng C.A. Meyer, whose structural elucidation was carried out by means of spectral analysis (including IR, HR-FAB-MS and NMR). This compound showed the moderate cytotoxic activities against U937 and HeLa cells by using the MTT method.

This document improved genetic algorithm and Intelligent discern points algorithmin chip placement and routing for Board-level photoelectric interconnection, by comparisonofthe algorithm results to verify the effectiveness and practicality of the improved algorithm. First introduced the features of chip placement and routing for Board-level Photoelectric Interconnection. Then describes the improved method of genetic algorithms and intelligent discern points algorithms. Finally, implement algorithm by C language on VC6.0++ platform, while the data import MATLAB to displays the optimal placement and routing results. The results show that the effectiveness of improved algorithm, which has a guiding significance for the chip placement and routing.