Abstract
Equipment fault diagnosis can increase productivity, product quality and life of machinery. However, the commercially available diagnostic tools cannot detect randomly occurring faults, and are too complex and expensive to use. For printing industry, the quality of the printed matters is not only affected by press faults but also by press settings, which are usually determined by printing experts. However, such experts are difficult and expensive to hire. Thus, the development of an expert and automated system is required. Two systems and a test form have been developed:-

1. an expert system which includes an effective Smart Electronic Ear (SEE) for monitoring and fault diagnosis of printing machinery;
2. an Intelligent Color Printing Quality Enhancement System (ICPS); and
3. a printing test form for quality evaluation of printed matters.

SEE is embedded with our "Exact" wavelet analysis and other advanced signal processing tools, such as active noise cancellation and multiple source separation. SEE is specially developed to minimize the problems of overlapping as observed in the conventional wavelet transforms. SEE can diagnose both periodically and randomly occurring faults. Since SEE is fully developed by virtual instrument, substantial saving can be obtained by reducing hardware type of instruments. Apart from printing machinery, SEE is also applicable to a wide range of industrial equipment.

ICPS is the first quality evaluation system for printing industry in Hong Kong. It possesses a knowledge base which stores huge printing knowledge in the form of facts, rules, heuristics, and procedures. The knowledge base will help press operators to set printing parameters properly and detect anomalous conditions during printing.

A printing test form is also designed to evaluate the performance of printing presses. This test form is the first form that is uniquely designed for China and Asian type of printed matters.

The project received financial support under the Innovation and Technology Fund of the HKSAR Government.

Contact Information
Mr H Y Wong
Director, Technology Transfer Office
City University of Hong Kong
83 Tat Chee Avenue
Kowloon, Hong Kong
Tel : (852) 2788 8428
Fax : (852) 2788 9119
Email : hy.wong@cityu.edu.hk The product of this project is an expert system which integrates both SEE and ICPS, and a customized test form. This project received financial support under the Innovation and Technology Fund of the HKSAR Government.

簡介
可靠的故障診斷及品質監測能提高生產效率和確保產品質量，更可有效地延長機器的壽命。在印刷行業裡，印刷品品質受多方面因素影響，如印刷機故障，以致開機前的準備不足及調較失當等亦是常見的問題。一直以來，業界都依賴有多年經驗的印刷師傅作品質監控，有關的人才越來越少而且薪酬相當高，而現有儀器價格昂貴，使用不便，且不能診斷突發性故障。選用自動化而成本較低的專家監控系統，將會是印刷管理層的新趨勢。有鑑於此，我們開發了一套專家系統。此系統結合了「智能耳」(SEE)和「智能色彩品質改善系統」(ICPS)，前者可有效監測印刷機的運作，分析錯誤，後者則配合發展一套適合內地及東南亞廠房的印刷樣張，用以監控印刷品品質。

「智能耳」(SEE) 是一項利用我們開發的 "Exact" 微波分析，並加入了其他先進的信號處理技術，如主導性消噪及盲源分離等。傳統的微波分析常重覆顯示問題所在，新的SEE改進了這方面的缺點，並對具有週期性及突發性特徵的機械故障均可作出成功診斷。由於SEE是一個軟體虛擬儀器，成本自然比市面上一般硬體監察儀器低，除印刷行業外，亦適合眾多工業採用。

ICPS是本港印刷業界首個印刷品品質評估系統。它包含了知識庫，儲存印刷專家的專業知識，如理論、定律、歸納及印刷程序等資料。這個知識庫可幫助機器操作員輸入適當的參數數據，用以探測不規則的印刷問題。

現時印刷業界一般使用歐美標準的印刷樣張以評估印刷機的表現。本計劃將為中國及東南亞廠房特別設計一套更合適的樣張標準。

本項目獲得香港政府的創新及科技基金資助。

查詢
香港城市大學技術轉移處處長黃漢儀先生
地址 : 香港九龍達之路83號
電話 : (852) 2788 8428
傳真 : (852) 2788 9119
電郵 : hy.wong@cityu.edu.hk