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Background: With the increase in the integration degree of the three-dimensional Integrated Circuit ( 3D I C) , the thermal power consumption per unit volume increases greatly, which makes the chip temperature rise. High temperature could affect the performance of the devices and even lead to thermal failure. So, the thermal management for 3D ICs is becoming a major concern. Objective: The aim of the research is to establish a micro-channel cooling model for a three-dimensional integrated circuit(3D IC) considering the through-silicon vias(TSVs). Methods: By studying the structure of the TSVs, the equivalent t hermal resistance of each layer was formulated. Then the one-dimensional micro-channel cooling thermal analytical model considering the TSVs was proposed and solved by the existing sparse solvers such as KLU. Results: The results obtained in this paper reveal that the TSVs can effectively improve the heat dissipation, and its maximal temperature reduction is about 10.75%. The theoretical analysis is helpful to optimize the micro-channel cooling system for 3D ICs. Conclusion: The TSV has an important influence on the heat dissipation of 3D IC, which can improve its heat dissipation characteristic.

The current flows in a porous media is a very complex nature phenomenon, and it is very difficult to establish its mathematical model with the traditional definition of derivative. In this paper, the fractal resistance-capacitance circuit of porous media is successfully established based on He?s fractal derivative, and the two-scale transform is adopted to solve the fractal circuit. In this fractal resistance-capacitance circuit circuit, the fractal dimension represents the effective porosity of the two plates of the capacitor, and the influence of its value on the fractal resistance-capacitance circuit circuit is also elaborated.

Local fractional calculus has gained wide attention in the field of circuit design. In this paper, we propose the zero-input response(ZIR) of fractal RC circuit modeled by local fractional derivative(LFD) for the first time. With help of the law of switch and the Kirchhoff Voltage Laws, the transient local fractional ordinary differential equation is established, and the corresponding exact solution behavior defined on Cantor sets is presented. What we found especially interesting was that the fractal RC becomes the ordinary one in the particular case κ = 1. The results obtained in this paper reveal that the local fractional calculus is a powerful tool to analyze the fractal circuit systems.

The through silicon via technology is a promising and preferred way to realize the reliable interconnection for 3-D integrated circuit integration. However, its size and the property of the filled-materials are two factors affecting the thermal behavior of the integrated circuits. In this paper, we design 3-D integrated circuits with different through silicon via models and analyze the effect of different material-filled through silicon vias, aspect ratio and thermal conductivity of the dielectric on the steady-state temperature profiles. The results presented in this paper are expected to aid in the development of thermal design guidelines for through silicon vias in 3-D integrated circuits.

For precision assembly of multiple species and variable batch productions, the existing problems are: assembly accuracy is low, and assembly efficiency is poor. This paper presents module design and optimization approaches for intelligent assembly system, meeting a large variety of assembly requirements. In addition, the connotation and components of the intelligent assembly system are described in detail. Then, based on the general functional integrity of the intelligent assembly system, the principle of module division about assembly system is proposed, and the basic functional modules have been divided. Taking the assembly accuracy, mass, work range, and work time as optimization targets, using genetic algorithm optimization method, we optimized the key modules’ sizes of assembly cell, and obtained the optimal sizes of key modules of the intelligent assembly system. The module design and optimization approaches can provide theoretical guidance and technical support to design the assembly system for precision microstructures.

Vertical integration for microelectronics possesses significant challenges due to its fast dissipation of heat generated in multiple device planes. This paper focuses on thermal management of a 3-D integrated circuit, and micro-channel cooling is adopted to deal with the 3-D integrated circuitthermal problems. In addition, thermal through-silicon vias are also used to improve the capacity of heat trans-mission. It is found that combination of microchannel cooling and thermal through-silicon vias can remarkably alleviate the hotspots. The results presented in this paper are expected to aid in the development of thermal design guidelines for 3-D integrated circuits.

An analytical thermal model is developed for N-die stacked chips with integrated micro-channels cooling. The model is implemented with some mathematical software. Comparison of the temperature predicted by the proposed model with some computer fluid dynamics software numerical results show excellent agreement, and the maximal relative error is less than 4.0%.

Impact and vibration are two of the thorniest technical problems to hybrid machine tool. In this paper, the kinematics principle of the hybrid machine tool was proposed as well as the suppression algorithm, which was based on the velocity optimal control algorithm (VOCA.). And this algorithm was carried out after fine interpolation. It was proved by experiment on hybrid machine tool that the impact was reduced effectively by this way. Account for the velocity optimal control algorithm, the velocity performance of the machine was improved, especially when kinematics calculation error occurred.

In order to meet the requirements raised by the surface strengthening and rolling technology of torsion shafts on heavy-duty armored vehicles, an open CNC system, based on PMAC, is developed. The paper covers a detailed description of its hardware and software. Experiments show that the introduction of rolling shafts processed by CNC rolling machines not only improves the surface roughness and abrasion resistance, but also raises endurance strength and production efficiency. Introduction