On-line Error-matching Measurement and Compensation Method for a Precision Machining Production Line

Shih-Ming Wang,Chun-Yi Lee,Hariyanto Gunawan,Chin-Cheng Yeh 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.2

When producing a matching part for good mating with its counterpart (assembly part), good matching accuracy between the matching part and assembly part is highly required. The matching errors are influenced by not only the errors of the matching part but also the errors of the assembly part. Because the errors of an assembly part could be different from others, it is very difficult to have very good mating accuracy, if the manufacturing of a matching part does not take the actual errors of the assembly into account. Furthermore, it will need additional off -line assembly mating tests to find a good mating pair. This study proposes an error-matching compensation method to solve the not-good-mating problem for manufacturing assembly modules with good matching accuracy. In this method, the actual errors of an assembly part are directly in-line measured and used to compensate the machining process of a matching part so that a dedicated part with the good mating condition can be on-line made for the error-measured assembly part. In addition to having better matching accuracy, this method also provides advantages of high production efficiency and cost saving, because it will not need the off -line mating test to find good mating pairs. This method also includes a function of in-line auto-generation of error compensation NC programs to support continuous production. In this study, error analysis of two mating types (planar mating and triangle mating) were explored and discussed. The Human–Machine Interface was built with the use of C# language. Finally, machining experiments with in-line measurements were conducted to verify the proposed method. The experimental results have shown the feasibility and effectiveness of the proposed method.

Adjusting Recreation Specialization Investments to Develop a Tourism Destination

Shih-Ming Ou,Ching Chang,Zong-Wei Zhu 세계문화관광학회 2010 Conference Proceedings Vol.11 No.0

This paper explores the question of how recreation specialization affects the development of a tourism destination over time. We formulate the development process as an optimal control problem by adjusting specialization investments for the purpose of either attracting more tourists or discouraging tourists from visiting. Our research suggests investment strategies for two types of tourism destination consistent with the intensity of correlation between recreational activities and degree of specialization. Our data show that when the influx of tourists exceeds the carrying capacity of a destination, tourism companies will reduce investment to avoid congestion. Otherwise, companies will increase expenditures to maximize profits.

A New Synchronous Error Control Method for CNC Machine Tools with Dual-Driving Systems

Shih-Ming Wang,Ren-Jeng Wang,Shambaljamts Tsooj 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

Driving an object along one axis with two driving systems is a common method for obtaining high acceleration and high trust force for a large CNC machine tool. However, if large synchronous movement error exists between the two driving systems, the machine will not be able to achieve high acceleration. Moreover, it may also cause serious structure deformation and damage to the machine. To solve this problem, a new control method integrating the model reference adaptive control and variable structure control was developed and verified in this study. The proposed method can determine and compensate on-line the synchronous movement errors between two driving systems so that the master driving unit and the slave driving unit of a dual-driving system can synchronously move with no large drag force and reach the desired acceleration. Experiments were performed on a gantry-type two-axis platform with a sliding 5-Kg metal block attached on the X-axis. The experimental results showed that the maximum and the average synchronous movement errors were reduced from 0.061 mm to 0.040 mm and from 0.032 mm to 0.013 mm, respectively.

On-machine Volumetric-error Measurement and Compensation Methods for Micro Machine Tools

Shih-Ming Wang,Ji-Jun Lin 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

The CNC micro machine tool is an essential of the micro machining process for manufacturing miniature high-tech products. A software-based error compensation method based on measured volumetric errors that can pre-compensate cutting path can further enhance a machine’s accuracy without increasing its manufacturing cost. Considering the limited workspace of a micro machine tool and the instrument cost, an on-machine and vision-based measurement method integrating machine vision method with use of 3 COMs and homogeneous transformation method was proposed in this study. Sensitivity analysis was conducted to analyze the influence of the CMOS pixel error to the measurement accuracy. To improve the machining accuracy, the measured errors were directly compensated to the machining trajectory with use of an error compensation method that consists of an element-free error interpolation scheme and a recursive software error compensation scheme. Experiments on a toggletype micro machine tool were conducted to verify the effectiveness of the proposed methods. The results have shown that the feasibility and effectiveness of the proposed methods. The tracking errors of the machine was further improved from (x = 7.9 μm, y = 4.1 μm) to (x = 5 μm, y = 3.7 μm).

Practice of Smart Manufacturing Implementation on Traditional Manufacturing Industry

Shih-Ming Wang 한국생산제조학회 2022 한국생산제조시스템학회 학술발표대회 논문집 Vol.2022 No.5

Prevalence and impacts of male urinary incontinence on quality of life, mental health, work limitation, and health care seeking in China, Taiwan, and South Korea (LUTS Asia): Results from a cross-sectional, population-based study

Ming-Chieh Cheng,Shih-Ping Liu,Yao-Chi Chuang,Karina Chin Po Hsu,Po-Ming Chow 대한비뇨의학회 2022 Investigative and Clinical Urology Vol.63 No.1

Purpose: Male urinary incontinence (UI) is a global health issue associated with bothersome symptoms which affect daily life. This study aims to evaluate the prevalence of male UI in China, Taiwan, and South Korea and to determine if UI is an independent risk factor affecting the health-related quality of life (HRQoL), mental health, work limitations, and healthcare seeking behavior. Materials and Methods: A post-hoc analysis was conducted on the LUTS Asia database which was collated from a cross-sectional, population-based internet survey in China, Taiwan, and South Korea. Prevalence of male UI was assessed, and the effect on HRQoL, Hospital Anxiety and Depression Scale (HADS) depression and anxiety scores, work performance, and healthcare seeking behaviors was determined using univariate and multivariate analyses. Results: A total of 4,076 male participants were surveyed. Prevalence of male UI was 17.3%. UI adversely affected the HRQoL in both physical and mental domains. Both multivariate and univariate analyses showed that male UI could be correlated with a negative effect on the HADS anxiety and depression scores. Multivariate analysis suggested that work difficulties were correlated to the presence of UI. Up to 28% of participants who reported urge UI only did not adopt any management measures. Conclusions: UI is common in men over 40 years and adversely impacts HRQoL. It is an independent risk factor for anxiety and depression and may cause significant work limitations. Despite these negative effects, many men still do not seek any intervention.

An On-Machine and Vision-Based Depth-Error Measurement Method for Micro Machine Tools

Shih-Ming Wang,Han-Jen Yu,Shih-His Liu,Da-Fan Chen 한국정밀공학회 2011 International Journal of Precision Engineering and Vol. No.

The error measurement method is an essential for further enhancing the machining accuracy of a micro machine tool. An on-machine vision-based measurement method that can measure 2-D contouring-/tracking errors of a micro machining process had been previously developed. An on-machine depth-error measurement method was proposed in this study to fulfill the complete 3-D machining errors measurement. The method adopts image re-constructive technology and camera pixel correction to provide non-contact measurement capability. To improve the measurement limits due to the pixel resolution and the filler of view of a CCD, a 2-step measurement method with use of a depth model was developed. Because of the capability of eliminating the shadow effects caused by the tilting light source, the proposed method provides more accurate and reliable measurement results. Sensitivity analysis was conducted to assess the influence of the CCD setup errors on the measurement accuracy for implementation. Experiment was conducted and the results have shown the effectiveness and feasibility of the measurement method.

Transcription regulatory pathways associated with hypoxia in Arabidopsis

Ming-Che Shih 한국육종학회 2014 한국육종학회 심포지엄 Vol.2014 No.07

Transcriptional control plays an important role in regulating submergence responses in plants. Although numerous genes are highly induced during hypoxia, their individual roles in hypoxic responses are still poorly understood. Through microarray studies, we identified a number of transcription factors (TF) that are induced in different stages of hypoxia. We have chosen two TFs, AtHRE1, which was specifically induced during hypoxia but not by cold, drought or dehydration, and WRKY22, which was rapidly and strongly induced upon submergence in Arabidopsis, for further studies. Our results suggest that in addition to ethylene an ethylene-independent signal is also required to mediate hypoxia induction of HRE1. Through a series of genetic and molecular analyses, we found that hypoxia-inducible genes could be affected by AtHRE1-RNAi lines in two different ways: hypoxic induction of glycolytic and fermentative genes was reduced, whereas induction of a number of peroxidase and cytochrome P450 genes was increased. Taken together, our results show that AtERF73/HRE1 is involved in modulating ethylene responses under both normoxia and hypoxia. We found that many genes in the WRKY transcription factor (TF) family were rapidly and strongly induced upon submergence in Arabidopsis. Notably, a large proportion of innate immunity marker genes were co-induced with WRKYs under submergence and other stresses. Compared to wild-type, WRKY22 T-DNA insertion mutants, wrky22-ko1 and wrky22-ko2, have lower submergence-acclimatized disease resistance. Submergence induction of innate immunity markers, such as FRK1 and WRKY53, were lower in these WRKY22 mutants. These results provide evidence that submergence triggers Arabidopsis immunity through WRKY22, allowing plants to defend simultaneous or sequential infection upon floods.

A Micro Cutter Auto-Alignment System with On-Machine Positioning Error Measurement and Compensation Methods

Shih-Ming Wang,Ji-Jun Lin,Zhe-Zhi Ye,Shambaljamts Tsooj,Chun-Chieh Wang 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

To perform an accurate micro machining process, accurate alignment of the micro cutter with respect to the local coordinate frame for machining is essential. Due to the fragility of the micro tool, traditional cutter alignment method used in industry is no longer proper for micro machining. Utilizing machine vision technology with 2 CCDs, a micro tool positioning error measurement and auto-compensation method and system were proposed. In the measurement method, Power Law Method was first used to enhance the image taken by a CCD. Canny Edge Method and image projection method were then used to identify the contours of the cutter and the workpiece from the image. Finally, the position errors of the cutter were determined through calculating the number of pixels between the cutter and the workpiece. The proposed error compensation system can automatically generate NC codes which will accurately re-locate the cutter based on the measured position errors . Experiments were conducted on a micro machine tool, and the results have shown that the y-dir. positioning error of the cutter was significantly improved from -0.025 mm to 0.001 mm, and the total machining error was reduced from -0.02 mm to -0.001 mm.

Study of an Efficient Real-Time Monitoring and Control System for BUE and Cutter Breakage for CNC Machine Tools

Shih-Ming Wang,Chien-Da Ho,Po-Cheng Tsai,Chuntai Yen 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

If machining abnormalities, such as build-up-edge and cutter breakage, occur during machining, serious damage on the workpiecesurface and deterioration of production efficiency will happen, and cause additional energy consumption for rework and increase themanufacturing cost. To minimize the effects, an on-line diagnosis method with use of Fast Fourier Transform and algorithm of shorttimesignal variation analysis was developed to analyze the vibration signals to quickly detect the two abnormalities in this study. Inaddition, the real-time machining information from CNC controller was extracted through a bi-lateral communication module toprevent misdiagnosis. The control commands were automatically generated by the proposed system and directly sent to the CNCcontroller to stop the machine for cutter replacement. Without complex computation, the system can detect the occurrence of BUEor cutter breakage within 1 second and complete machine control within 3 seconds. The system can instantly transmit and save thereal machining information and diagnosis/control results to the remote central monitoring platform for further process improvement. With use of TCP/IP communication protocol the central monitoring platform can remote log into the on-site monitoring computer todirectly operate the diagnosis/control system. Experimental results showed the feasibility and effectiveness of the proposed system.