A Study of Massively Parallel Molecular Computing - Creating IntBrconnection'Free Computers -

VLSI电路复杂度的指数级增长使得互连问题变得尤为严重。本研究计划从集成电路技术和基础计算机科学的角度探讨无互连分子计算的可能性。以下是本项目的主要成果：我们提出了一个用于分子计算的人工催化剂装置的基本模型，并研究了一些可能的装置实现方法。我们研究了利用人工催化剂装置的集体行为诱导的反应扩散动力学来实现大规模并行计算的可能性，这些装置是在二维衬底上制造的。作为演示所提出概念的第一步，我们开发了一个氧化还原微阵列的实验模型，该微阵列由铂微电极的二维阵列组成，每个微电极都作为人工催化剂装置。我们证实了氧化还原微阵列可以在阵列表面的薄液体层中控制可逆的氧化还原反应，并可以实现人工可激发的反应扩散动力学。我们成功地观察到活性化学波在液体层内的传播。我们研究了一种系统的方法来设计人工反应扩散动力学来进行特定的图像/模式处理。我们采用数字反应扩散系统（DRDSs）的框架进行理论讨论，这是一种特殊的具有图案/纹理形成能力的多维数字滤波器。我们在DRDS的基础上开发了一种新的纹理图像恢复算法，如指纹图像。我们还开发了一种使用可兴奋drds的任意2D/3D地图的最短路径搜索算法。进一步研究分子计算系统的设计方法是今后的研究课题。

The exponential growth of VLSI circuit complexity causes interconnection problems to become particularly severe. This research project is to investigate a possibility of interconnectionfree molecular computing from the viewpoint of integrated circuit technlogy as well as fundametal computer science. Listed below are major results of this project:1. We proposed a basic model of artificial catalyst devices for molecular computing, and investigated some possible approaches to device implementation. We investigated a possibility of realizing massively parallel computation using reaction-diffusion dynamics induced by a collective behavior of artificial catalyst devices, which are fabricated on a 2D substrate. As a first step for demonstrating the proposed concept, we developed an experimental model of a redox microarray consisting of a two-dimensional array of platinum microelectrodes, each of which works as an artificial catalyst device. We confirmed that the redox microarray could control reversible redox reactions in a thin liquid layer on the surface of the array, and could realize artificial excitable reacton diffusion-dynamics. We successfully observed active chemical-wave propagation within the liquid layer.2. We investigated a systematic way of designing artificial reactiondiffusion dynamics for performong specific image/pattern processing. We employed the framework of Digital Rraction Diffusion Systems (DRDSs) --- a special class of multidimensional digital filters having pattern/texture formation capability --- for theoretical discussion. Wedveloped a new restoration algorithm for texture images, such as fingerprint images, on the basis of DRDS. We also developed a shortest path search algorithm for arbitrary 2D/3D maps using excitable DRDSs.Further investigations on a systematic way of designing molecular computing systems are deing left as future research subjects.