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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. (Contains 1 figure and 8 tables.)

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. Index Terms--Gray system theory, IC marking, inspection, machine vision.

Image enhancement is an essential procedure in machine vision-based inspection. In practical applications, image enhancement is usually a part of image pre-processing, intended to make the following inspection more effective. The image enhancement method is usually selected by trial-and-error or on the basis of experience. This paper presents an automatic procedure for fast and effective image enhancement. The procedure uses multivariate analysis to automatically construct an optimal image enhancement model. First, an optimally enhanced image was selected from the literature as a basis for the model. Then, the image features were identified and Wilks' statistic was used for feature selection. Next, discriminate functions were built to select the optimal image enhancement method. To verify the model, 53 training images from the literature and 12 test images from a local company were used in an experimental analysis. The model achieved 98.11% accuracy in selecting the most suitable image enhancement method, and the average increase in contrast was 98% for the 53 training images. The enhancement method selection results for the 12 test images were also in agreement with the 53 training images from the literature. The results show that the proposed method is effective and appropriate for quickly improving image contrast. [ABSTRACT FROM AUTHOR]

The microwave communication substrate is currently using manual inspection from ultrasonic image. The bubble defect ratio is an important index for evaluating the quality of the substrate. It is difficult to formalise standards for the quality inspection procedure by an operator since different numbers of bubbles may be realised. This paper proposes a novel inspection procedure for the calculation of the bubble ratio of microwave communication substrate. First, the optimal threshold is determined for binary image segmentation on the basis of a co-occurrence matrix. Further, the image of the microwave communication substrate is divided into three parts, namely, the image skeleton area, soldering area, and IC working area. The image subtraction technique is used to obtain the global and critical regions for bubbles. After data analysis, if the critical region bubble ratio is larger than 10% of the critical region, then it is judged to be a defect. When a substrate is judged to be non-defective, we should further proceed with the global area detection. If the global region bubble ratio is larger than 12.3% of the global region, then it is judged as a defect. An experiment was conducted to demonstrate the application of this technique. The results showed that the inspection accuracy reached 97.49%. The results of this study provide an effective solution for the inspection of the interface bond quality of a microwave communication substrate. [ABSTRACT FROM AUTHOR]

Most industrial problems involve multiple-quality characteristics. The methods used for optimising such a multiple-response problem are those normally used for dealing with a single response problem, such as the experimental design, response surface methods (RSM) and regression techniques. There is a major difficulty with this traditional approach on the point estimation of the optimal solution, thus the obtained solution may not be practically feasible. In this research, a simulated regression approach via Monte Carlo simulations and the nonlinear optimisation via the trust-region methods were used to determine an optimal operational region (OOR). In practice, an engineer can refer to this region for adjusting manufacturing parameters in the production environment to minimise the response variations. An example with three controllable variables is used to demonstrate the application of the proposed methodology. [ABSTRACT FROM AUTHOR]

During the past decade, a variety of 'run-to-run' (R2R) control schemes have been proposed and investigated extensively using various semiconductor manufacturing methods. However, such control has a problem when it is suddenly faced with a larger process change that does not satisfy the control requirements. In view of this situation, a new process control framework is proposed, which integrates response surface modelling, evolutionary operation (EVOP) and R2R control principles. The primary objective of this study is to improve dynamic model parameter prediction, enabling more effective optimized recipe calculations. The recursive least squares (RLS) algorithm is used to evaluate changes in the process parameters. If the evaluated parameter values exceed a joint parameter threshold, the recipe moves to a new optimum point. This movement, which continuously applies the design of experiment (DOE) concepts to collect process data in the experimental range, uses this data with the least squares error (LSE) method to estimate the new model parameters. Then, the renewed model applies the minimized total cost principle (the cost function structure includes an expected off-target and controllable factors adjustment) and uses the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm to obtain a recipe for the next period. Simulation studies show that the proposed system has better control performance than the traditional self-tuning controller. In the relevant chemical mechanical planarization (CMP) application of semiconductor manufacturing, one critical chip fabrication step is also used to illustrate the proposed control procedure in a dynamic process. [ABSTRACT FROM AUTHOR]

BGA (Ball Grid Array) surface defect detection requires faster and more accurate methods for semiconductor industry applications. Traditionally, the BGA inspection used gray-scale images. However, the solder pad, wiring and gray scales shown in images depict little variance. Therefore, when the threshold value is poorly set or the contract rate is insignificant, BGA detection may fail to segment an object. This research proposes a modified methodology that uses Gamma correction for image enhancement. Three-color bands were applied to a modified Gamma correction algorithm (i.e. RGB) to better separate the high and low image contrasts. Better results were obtained by dividing the image into background and foreground portions using the Gamma correction. As a result, the proposed method improved the contrast value by 52.09%. After the images were enhanced and segmented, the compactness and internal holes were calculated as features for classification. The results showed that classification correctness was 96.43%. The proposed method used a 640 × 480 pixel image, performing complete defect detection 0.3 seconds faster than the traditional enhancement method, which requires 1 second. The research results provide an effective solution for the detection and classification of the BGA surface tin ball defect problem. [ABSTRACT FROM AUTHOR]

During the past decade, a variety of 'run-to-run' (R2R) control schemes have been proposed and extensively investigated under various assumed models of process dynamics and disturbances whilst applied to the setpoints (recipe) adjustment between batches for the production of semiconductor manufacturing. The R2R control mechanism of this kind represents an interdisciplinary methodology combining response surface modelling, engineering process control (EPC) and statistical process control (SPC), of which the main objective is to fine-tune the recipe so as to maintain the process output of each run as close to the nominal target as possible. In this paper, the single-input single-output (SISO) case is addressed. To overcome the shortcomings in published R2R controllers, an EWMA feedback controller through a strategy of triple smoothing is proposed (in line with the construction of EWMA statistics) which, in the standard R2R practice, compensates process shifts, a deterministic process drift, disturbance of coloured noises, as well as positive autocorrelation (up to the autoregressive order of two) present in the observed response. It is shown via an experimental study that the triple EWMA filter can provide better control performance for R2R applications as compared with those of the control actions of double EWMA and self-tuning (ST). At last, a relevant application to chemical mechanical planarization (CMP) in semiconductor manufacturing, a critical step in chip fabrication, is used to illustrate the proposed controller. [ABSTRACT FROM AUTHOR]

Before a machine vision system can be used effectively in a production environment, its capability (accuracy and repeatability) must be determined. In this project, a Taguchi methods-based systematic methodology is used to determine a vision system's three-dimensional (3D) coordinate measurement capability. This methodology reduces the effect of the noise factors rather than removes them which may be costly. Seven factors (i.e., lens type, colour of background, distance between two objects, distance between camera and target, filter, lighting source, and angle between the camera's optic axis and the target's surface) are studied in an L[sub 27](3[sup 13]) orthogonal array. The experiment results show that when set up correctly, the selected vision system can measure to 0.004 inch (1 in. = 25.4 mm) of accuracy and 0.001 in. of repeatability. The process capability percent and response figures show the amounts of change when the setup factor levels deviate from the optimal one. [ABSTRACT FROM AUTHOR]

This research utilized a biomechanical approach for the investigation of body weight effects in a manual-lifting activity. Following a 3-day training session, 10 male subjects performed 6 tasks in 12 trials. For each trial, the subject was directed to use a free style posture to lift a weighted box from the floor to a 0.762 m high shelf. In order to evaluate the forces and torques generated by the external load and the body weight acting on the articulations and vertebra during the lifting task, the experimenter used a high-speed camera to record the lifting activity, a GP-8 Sonic Digitizer to translate the motion into coordinates, and a biomechanical program to calculate the forces acting on the L5/S1 disc, the maximum abdominal force, and the torque acting on the abdomen. After the statistical analysis, two regression models were developed, which provide a convenient and useful means to quantify the maximum compressive and shear forces acting on the low back area during a sagittal plane-lifting activity. The model for the maximum compressive force acting on the L5/S1 disc in kilograms accounted for 95% of the variability in observed data (R² = 0.9506); the model for the maximum shear force acting on the same disc in kilograms accounted for 93% of the variability in observed data (R² = 0.9269). [ABSTRACT FROM AUTHOR]

Describes a procedure for designing and evaluating manual materials handling tasks. Aim of eliminating worker risk; Analysis of lifting, lowering, carrying, pushing and pulling, frequency of handling and height and distance of handling; Creation of a risk potential index to evaluate the acceptance and rejection of each task element.

The aim of this study is to see if the centre of pressure (COP) measurements on the postural stability can be used to represent the electromyography (EMG) measurement on the activity data of lower limb muscles. If so, the cost-effective COP data measurements can be used to indicate the level of postural stability and lower limb muscle activity. The Hilbert-Huang Transform method was used to analyse the data from the experimental designed to examine the correlation between lower-limb muscles and postural stability. We randomly selected 24 university students to participate in eight scenarios and simultaneously measured their COP and EMG signals during the experiments. The Empirical Mode Decomposition was used to identify the intrinsic-mode functions (IMF) that can distinguish between the COP and EMG at different states. Subsequently, similarity indices and synchronization analyses were used to calculate the correlation between the lower-limb muscle strength and the postural stability. The IMF5 of the COP signals and the IMF6 of the EMG signals were not significantly different and the average frequency was 0.8 Hz, with a range of 0-2 Hz. When the postural stability was poor, the COP and EMG had a high synchronization with index values within the range of 0.010-0.015. With good postural stability, the synchronization indices were between 0.006 and 0.080 and both exhibited low synchronization. The COP signals and the low frequency EMG signals were highly correlated. In conclusion, we demonstrated that the COP may provide enough information on postural stability without the EMG data. [ABSTRACT FROM AUTHOR]