Bernard C. Jiang

Machine vision-based gray relational theory applied to IC marking inspection

In the semiconductor industry, IC marking error remains a problem. The objective of this study is to identify IC marking using gray relational analysis. The gray theorem determines the gray relational grades of all of the selected factors by choosing the highest gray relational grade, even under incomplete information circumstances. In an IC marking identification procedure, an image is rotated and segmented first. Second, thresholding and thinning operations are applied to reduce the calculation complexity and extract features from the segmented image. Finally, the gray relational analysis method is applied to inspect the IC markings. The identification rate reaches 97.5%. As compared to traditional methods, there are three advantages in gray relational analysis: 1) No large amount of data is needed; 2) No specific statistical data distribution is required; and 3) There is no requirement for the independency of the factors to be considered. It is an easy and practical method in the field of IC marking inspection.

Liquid crystal display surface uniformity defect inspection using analysis of variance and exponentially weighted moving average techniques

Display quality is part of the final liquid crystal display (LCD) inspection process before shipping. A ‘limited sample’ is provided based on the agreement between the manufacturer and the customer. This inspection usually includes an operator who compares the LCD product with the limit sample using the naked eye. The procedure often causes controversy in the manufacturing plant and between the manufacturer and customers. This study attempts to establish a more objective, automatic method to determine the MURA-type defects in LCD panels. A luminance meter is used as the measurement device. An LCD panel is divided into 144 areas. Five points are measured to obtain the luminances. Analysis of variance and the exponentially weighted moving average techniques are applied to determine the existence of MURA defects. Fifty normal LCD panels and 50 MURA defects panels were used to test the inspection method. All 50 LCD panels with MURA defects were correctly identified using the proposed inspection method. The proposed inspection method can help LCD manufacturers reduce the variation in LCD panel inspection results and establish a better relationship with customers through a common inspection mechanism.

A review of recent developments in robot metrology

Abstract This paper provides a review of various measurement techniques, and testing methods, conditions and specifications (TMCS) for determining performance of a robot. First, the principles of eperation, accuracy and repeatability of measurement systems, and any special features are summarized. Then, the TMCS proposed by the Robotic Industries Association, the International Organization for Standardization, a Japanese standard testing proposal, and several individuals are reviewed, and future research needs are identified.

3-D camera calibration using vanishing point concept

Abstract A three-dimensional (3-D) camera calibration technique that uses two-dimensional (2-D) grid paper and a vanishing point concept was developed and tested. The calibration technique does not require knowledge of the precise location of the calibration target as other calibration techniques require. The algorithm developed consists of the following steps: (1) Use a point-finder program with a subpixel interpolation technique to identify the points on a grid. (2) Apply an equalization procedure. (3) Use a line-finder program with a statistical linear regression technique to identify a line. (4) Repeat Steps 1 and 2 until all the lines are found. Then divide the lines into two groups—horizontal and vertical. (5) Determine one vanishing point for all the horizontal lines and one vanishing point for all the vertical lines. (6) Using the same vanishing point concept, determine the vanishing points for the planes of sight in space (horizontal and vertical). (7) Determine the camera location and rotational matrix. By using statistical methods, resolution at the subpixel level was achieved. Commercially available components were used in the vision system for this project. The results of the two tests showed that a low-cost vision system can make 3-D coordinate measurements as exact as 5 mils (0.005 inches) in accuracy and 1 mil in repeatability when properly set up and used with this calibration technique.

Using data mining techniques for multi-diseases prediction modeling of hypertension and hyperlipidemia by common risk factors

Research highlights? This paper proposes a two-phase analysis procedure to simultaneously predict hypertension and hyperlipidemia. ? Common risk factors of these diseases picked up by data mining and majority vote. ? This study uses common risk factors to build MARS predictive models for hypertension and hyperlipidemia. Many previous studies have employed predictive models for a specific disease, but fail to note that humans often suffer from not only one disease, but associated diseases as well. Because these associated multiple diseases might have reciprocal effects, and abnormalities in physiological indicators can indicate multiple associated diseases, common risk factors can be used to predict the multiple associated diseases. This approach provides a more effective and comprehensive forecasting mechanism for preventive medicine. This paper proposes a two-phase analysis procedure to simultaneously predict hypertension and hyperlipidemia. Firstly, we used six data mining approaches to select the individual risk factors of these two diseases, and then determined the common risk factors using the voting principle. Next, we used the Multivariate Adaptive Regression Splines (MARS) method to construct a multiple predictive model for hypertension and hyperlipidemia. This study uses data from a physical examination center database in Taiwan that includes 2048 subjects. The proposed analysis procedure shows that the common risk factors of hypertension and hyperlipidemia are Systolic Blood Pressure (SBP), Triglycerides, Uric Acid (UA), Glutamate Pyruvate Transaminase (GPT), and gender. The proposed multi-diseases predictor method has a classification accuracy rate of 93.07%. The results of this paper provide an effective and appropriate methodology for simultaneously predicting hypertension and hyperlipidemia.

A cause-and-effect analysis of robot accidents

Abstract Jiang, B.C. and Gainer, C.A., Jr., 1987. A cause-and-effect analysis of robot accidents. Journal of Occupational Accidents , 9: 27–45. Reported cases of robot accidents involving fatality, injury and non-injury were gathered from several sources (U.S., West Germany, Sweden and Japan). In cases where adequate information was available a cause-effect analysis of these accidents was performed. A total of 32 accidents were analyzed in the study. The accident effects were grouped according to who was injured (line worker, maintenance worker or programmer), the type of injury (pinch-point, impact or other), and the degree of injury (fatal, non-fatal-lost-work or non-fatal-no-lost-work). The accident causes were grouped into four categories (human error, workplace design, robot design and other) with the possibility that an accident could have more than one cause. Findings indicate that line workers are at greatest risk, followed by maintenance workers and programmers. Pinch-point accidents accounted for 56% of all accidents while impact accidents accounted for 44%. Most accidents were caused by poor workplace design (20 of 32 accidents) and human error (13 of 32 accidents). A comprehensive cause-effect analysis was performed on 25 of the accidents and includes: the accident source, the accident cause, the accident effect in terms of human injury, recommended guidelines to be implemented, and applicable safety standards in each case. Conclusions are drawn on the effectiveness of worker safety training and workplace design, both a result of suggested standards.

Psychophysical modelling for combined manual materials-handling activities.

Most psychophysical studies in manual materials handling (MMH)are involved only with single MMH activities, i.e. lifting, lowering, carrying, holding, pushing or pulling. Very little research has been reported on the determination of operator capacities for combinations of MMH activities (e.g. lifting a box, then carrying the box, or carrying a box, then lowering the box). These kinds of combined activities are prevalent in industry and in our daily lives. The objective of this study was to utilize the psychophysical approach to examine the effects of combinations of lifting, carrying and lowering activities. Twelve male students served as subjects for the study. The capacities that were determined as the maximum acceptable workloads for a 1-h work period for four individual MMH activities—lifting from floor to knuckle height (LFK), lifting from knuckle to shoulder height (LKS), lowering from knuckle to floor height (LOW) and carrying for 3·4 m (C) —and three combined MMH activities—LFK + C, LFK + C + LKS...

An empirical study of industrial engineering and management curriculum reform in fostering students’ creativity

The objective of this paper is to examine the effectiveness of a creativity-fostering program in industrial engineering and management (IE&M) curriculum reform. Fostering creativity in students has become a crucial issue in industrial engineering education. In a survey of previous studies, we found few on IE&M curriculum reform. In particular, no study has dealt directly with fostering students’ creativity. In this study, we propose an IE&M curriculum reform program. The core of this program is intended to enhance students’ creative problem solving ability. Based on this concept, three required courses were developed: industrial communication, creative problem solving, and scientific research methodology. To investigate the effectiveness of this curriculum reform program, we conducted a two-year follow-up study. One hundred seventy-seven IE&M undergraduates from Yuan-Ze University participated this study, and Torrance Tests of Creative Thinking (TTCT) were used to measure changes in their creativity. The results showed that the students, after completing this reformed curriculum program, had significantly improved their creativity.

Multivariate Multiscale Entropy Applied to Center of Pressure Signals Analysis: An Effect of Vibration Stimulation of Shoes

Falls are unpredictable accidents and resulting injuries can be serious to the elderly. A preventative solution can be the use of vibration stimulus of white noise to improve the sense of balance. In this work, a pair of vibration shoes were developed and controlled by a touch-type switch which can generate mechanical vibration noise to stimulate the patient’s feet while wearing the shoes. In order to evaluate the balance stability and treatment effect of vibrating insoles in these shoes, multivariate multiscale entropy (MMSE) algorithm is applied to calculate the relative complexity index of reconstructed center of pressure (COP) signals in antero-posterior and medio-lateral directions by the multivariate empirical mode decomposition (MEMD). The results show that the balance stability of 61.5% elderly subjects is improved after wearing the developed shoes, which is more than 30.8% using multiscale entropy. In conclusion, MEMD-enhanced MMSE is able to distinguish the smaller differences between before and after the use of vibration shoes in both two directions, which is more powerful than the empirical mode decomposition (EMD)-enhanced MSE in each individual direction.

Development of a fuzzy decision model for manufacturability evaluation

A manufacturability evaluation decision model is formulated and analyzed based on fuzzy logic and multiple attribute decision-making under the concurrent engineering environment. The study emphasizes on the treatment of the linguistic and vagueness at the early product development stage. The study also considers the function integration of the total life cycle of a product. Hence, the integrated decision model covers the multi-level, multi-goal requirements of the products. Multiple criteria such as the goal space, the decision space, the function space, the development (i.e., product & process design) space, and the activity space, are then applied under different analysis of decision-making methods. For instances, the fuzzy multiple attribute decision-making (FMADM) combined with activity-based costing (ABC) can be used in the activity decision space. The fuzzy logic decision model can be applied in the goal decision space. The results of this study point out the importance of early decision making capability. An example of a high-pressure vessel is provided to demonstrate the proposed model for evaluating the manufacturability.