Jim Lai - Academia.edu (original) (raw)
Papers by Jim Lai
2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)
The purpose of this paper is to consider the impact of humidity and temperature on the electrical... more The purpose of this paper is to consider the impact of humidity and temperature on the electrical properties of printed circuit boards (PCBs). PCB base materials are glass reinforced thermosetting laminates using a variety of resin systems with different loss characteristics. Test results indicate humidity has little impact on electrical properties of inner layer. It is difficult for moisture to penetrate into the PCB due to barriers created by copper ground planes. Conversely, temperature has a significant influence on PCB's electrical properties. Increasing temperature from 20 to 80 degrees C has a limited impact on dielectric constant (<; 3%) for all material types: standard loss, middle loss, low loss and ultra-low loss materials. The impact of increased temperature, 20 to 80 degrees, on loss tangent is more significant. Increasing temperature from 20 to 80 degrees C will influence loss tangent according to material type ranging from 10.4% for ultra-low loss to 38.7% for standard loss materials.
: The present Phase II of Smart Prosthetic Hand Technology focuses on the four closely connected ... more : The present Phase II of Smart Prosthetic Hand Technology focuses on the four closely connected areas of EMG signal identification and estimation, hand motion estimation, intelligent embedded systems and control, robotic hand and biocompatibility and signaling. The developed identification algorithm using a new sensor array, a proposed hybrid estimation algorithm will provide for the decomposition and inference of multiple signals. Different categories of amputation level will be simulated and the identification of EMG signals will be tested and adapted to these different cases. Next, the proposed sensing and actuation system for the artificial hand overcomes the limitations on dexterous manipulation of the prosthetic hands. Strategies on grasping and manipulation will be developed to complement the myoelectric signals. The proposed fusion of soft and hard embedded control systems strategy will alleviate the present problems associated with prosthetic devices. Finally, by investiga...
Proceedings of the 1989 ACM/IEEE conference on Supercomputing - Supercomputing '89
The inverse solutions of a robotic systems are generally produced by a serial process. Due to the... more The inverse solutions of a robotic systems are generally produced by a serial process. Due to the computing time of processing geometry data and generating an inverse solution corresponding to a specified point in Cartesian trajectory is larger than the sampling period, the missing points in the joint space are generated by some interpolation schemes (linear or cubic spline interpolations)
Journal of Shoulder and Elbow Surgery
BACKGROUND Cutibacterium acnes is the most common pathogen in shoulder prosthetic joint infection... more BACKGROUND Cutibacterium acnes is the most common pathogen in shoulder prosthetic joint infections. Short-contact benzoyl peroxide (BPO) solutions effectively reduce C acnes loads on the shoulder preoperatively. It is unknown how long the effect of BPO lasts. We evaluated C acnes counts 1 week after BPO application. We hypothesized that BPO would decrease C acnes burden with a rebound after 1 week. METHODS Screening of 102 healthy volunteers with no history of shoulder surgery or C acnes infection was performed to establish bacterial counts. Thirty-four participants were selected based on an established threshold. Each was given BPO 5% for 3 consecutive days of application on either the left or right shoulder as indicated by a random number generator. Deep sebaceous gland cultures were obtained with a detergent scrub technique before BPO application, after 3 days of use, and 1 week after BPO treatment commenced. RESULTS The differences between the logarithmic reduction and the logarithmic rebound at the anterior, lateral, and posterior sites were statistically significant. Anteriorly, the average log reduction was -0.44 and the average log rebound was 0.69 (P = .003). Laterally, reduction was -0.64 and rebound was 0.74 (P = .003). Posteriorly, reduction was -0.63 and rebound was 0.78 (P = .008). At the axilla, reduction was -0.40 and rebound was 0.31 (P = .10). The differences in C acnes burden between pretreatment and 1-week counts at all sites were not statistically significant. CONCLUSION A significant decrease in C acnes burden occurred after BPO application but was not permanent. Significant rebound occurred just 1 week later.
Journal of Bone and Mineral Research
Patients with Hutchinson-Gilford progeria syndrome (HGPS) have low bone mass and an atypical skel... more Patients with Hutchinson-Gilford progeria syndrome (HGPS) have low bone mass and an atypical skeletal geometry that manifests in a high risk of fractures. Using both in vitro and in vivo models of HGPS, we demonstrate that defects in the canonical WNT/b-catenin pathway, seemingly at the level of the efficiency of nuclear import of b-catenin, impair osteoblast differentiation and that restoring b-catenin activity rescues osteoblast differentiation and significantly improves bone mass. Specifically, we show that HGPS patientderived iPSCs display defects in osteoblast differentiation, characterized by a decreased alkaline phosphatase activity and mineralizing capacity. We demonstrate that the canonical WNT/b-catenin pathway, a major signaling cascade involved in skeletal homeostasis, is impaired by progerin, causing a reduction in the active b-catenin in the nucleus and thus decreased transcriptional activity, and its reciprocal cytoplasmic accumulation. Blocking farnesylation of progerin restores active b-catenin accumulation in the nucleus, increasing signaling, and ameliorates the defective osteogenesis. Moreover, in vivo analysis of the Zmpste24-/-HGPS mouse model demonstrates that treatment with a sclerostin-neutralizing antibody (SclAb), which targets an antagonist of canonical WNT/b-catenin signaling pathway, fully rescues the low bone mass phenotype to wild-type levels. Together, this study reveals that the b-catenin signaling cascade is a therapeutic target for restoring defective skeletal microarchitecture in HGPS.
The American journal of sports medicine, 2018
Massive rotator cuff tears (RCTs) begin as primary tendon injuries and cause a myriad of changes ... more Massive rotator cuff tears (RCTs) begin as primary tendon injuries and cause a myriad of changes in the muscle, including atrophy, fatty infiltration (FI), and fibrosis. However, it is unclear which changes are most closely associated with muscle function. To determine if FI of the supraspinatus muscle after acute RCT relates to short-term changes in muscle function. Controlled laboratory study. Unilateral RCTs were induced in female rabbits via tenotomy of the supraspinatus and infraspinatus. Maximal isometric force and rate of fatigue were measured in the supraspinatus in vivo at 6 and 12 weeks after tenotomy. Computed tomography scanning was performed, followed by histologic analysis of myofiber size, FI, and fibrosis. Tenotomy resulted in supraspinatus weakness, reduced myofiber size, FI, and fibrosis, but no differences were evident between 6 and 12 weeks after tenotomy except for increased collagen content at 12 weeks. FI was a predictor of supraspinatus weakness and was stron...
Journal of the Chinese Institute of Engineers
Abstract Recognizing 3‐D objects from 2‐D images has been an important area of research in comput... more Abstract Recognizing 3‐D objects from 2‐D images has been an important area of research in computer vision. In this paper, an efficient method is developed to determine the position and the orientation of a 3‐D polyhedron in a noisy image. This method assumes that the direction of a straight line on an image can be determined from noisy data. A set of linear equations are used to determine the orientation of an object. In cases where there are not enough straight lines of an image presented, the constraint equations can be introduced and the iterative process is applied. However the iterative process is simple and the divergence is not a problem. After the orientation is determined, the straight lines, corresponding to the visible edges of the object, are used to determine the intersection points. From the intersections and the corresponding corners of the polyhedron, another set of linear equations are used to obtain the position of the object. If the sum of the perpendicular distances, between the endpo...
Journal of the Chinese Institute of Engineers
Abstract In this paper, two methods, the Individual Calibration Method (ICM) and the Simultaneous... more Abstract In this paper, two methods, the Individual Calibration Method (ICM) and the Simultaneous Calibration Method (SCM), are used to calibrate a vision system with two cameras. The first approach calibrates a camera individually. For the second approach, two or more sets of camera intrinsic and extrinsic parameters are determined simultaneously such that the position errors for the 3‐D points are minimized. We show, theoretically and experimentally, the following results: (a) the offsets of the image centers do not affect significantly the position and orientation of a coordinate frame with respect to a stereo vision system with two cameras; (b) the lens distortion will not change dramatically the position and orientation of a coordinate frame with respect to a stereo vision system. We also find that (a) there is a difference in the determination of an object's location for the simultaneous and individual calibration methods; (b) the approach of calibrating two cameras simultaneously has the advantage ...
Journal of the Chinese Institute of Engineers
... Jim ZC Lai* and Shyh-Hwa Chyi Department of Information Engineering Feng Chia University Taic... more ... Jim ZC Lai* and Shyh-Hwa Chyi Department of Information Engineering Feng Chia University Taichung, Taiwan 40724, ROC ... The interpolated position points Page 3. JZC Lai & SH Chyi: A Parallel Algorithm for Generating Set Points in Cartesian Space for Spline Motion 41 Pi+1 ...
Journal of the Chinese Society of Mechanical Engineers Transactions of the Chinese Institute of Engineers Series C, 1992
Signal Processing, Apr 1, 2010
Pattern Recognition, Nov 1, 2009
In this paper, we present a fast k-means clustering algorithm (FKMCUCD) using the displacements o... more In this paper, we present a fast k-means clustering algorithm (FKMCUCD) using the displacements of cluster centers to reject unlikely candidates for a data point. The computing time of our proposed algorithm increases linearly with the data dimension d, whereas the computational complexity of major available kd-tree based algorithms increases exponentially with the value of d. Theoretical analysis shows that our method can reduce the computational complexity of full search by a factor of SF and SF is independent of vector dimension. The experimental results show that compared to full search, our proposed method can reduce computational complexity by a factor of 1.37-4.39 using the data set from six real images. Compared with the filtering algorithm, which is among the available best algorithms of k-means clustering, our algorithm can effectively reduce the computing time. It is noted that our proposed algorithm can generate the same clusters as that produced by hard k-means clustering. The superiority of our method is more remarkable when a larger data set with higher dimension is used.
2016 Asia-Pacific International Symposium on Electromagnetic Compatibility (APEMC)
The purpose of this paper is to consider the impact of humidity and temperature on the electrical... more The purpose of this paper is to consider the impact of humidity and temperature on the electrical properties of printed circuit boards (PCBs). PCB base materials are glass reinforced thermosetting laminates using a variety of resin systems with different loss characteristics. Test results indicate humidity has little impact on electrical properties of inner layer. It is difficult for moisture to penetrate into the PCB due to barriers created by copper ground planes. Conversely, temperature has a significant influence on PCB's electrical properties. Increasing temperature from 20 to 80 degrees C has a limited impact on dielectric constant (<; 3%) for all material types: standard loss, middle loss, low loss and ultra-low loss materials. The impact of increased temperature, 20 to 80 degrees, on loss tangent is more significant. Increasing temperature from 20 to 80 degrees C will influence loss tangent according to material type ranging from 10.4% for ultra-low loss to 38.7% for standard loss materials.
: The present Phase II of Smart Prosthetic Hand Technology focuses on the four closely connected ... more : The present Phase II of Smart Prosthetic Hand Technology focuses on the four closely connected areas of EMG signal identification and estimation, hand motion estimation, intelligent embedded systems and control, robotic hand and biocompatibility and signaling. The developed identification algorithm using a new sensor array, a proposed hybrid estimation algorithm will provide for the decomposition and inference of multiple signals. Different categories of amputation level will be simulated and the identification of EMG signals will be tested and adapted to these different cases. Next, the proposed sensing and actuation system for the artificial hand overcomes the limitations on dexterous manipulation of the prosthetic hands. Strategies on grasping and manipulation will be developed to complement the myoelectric signals. The proposed fusion of soft and hard embedded control systems strategy will alleviate the present problems associated with prosthetic devices. Finally, by investiga...
Proceedings of the 1989 ACM/IEEE conference on Supercomputing - Supercomputing '89
The inverse solutions of a robotic systems are generally produced by a serial process. Due to the... more The inverse solutions of a robotic systems are generally produced by a serial process. Due to the computing time of processing geometry data and generating an inverse solution corresponding to a specified point in Cartesian trajectory is larger than the sampling period, the missing points in the joint space are generated by some interpolation schemes (linear or cubic spline interpolations)
Journal of Shoulder and Elbow Surgery
BACKGROUND Cutibacterium acnes is the most common pathogen in shoulder prosthetic joint infection... more BACKGROUND Cutibacterium acnes is the most common pathogen in shoulder prosthetic joint infections. Short-contact benzoyl peroxide (BPO) solutions effectively reduce C acnes loads on the shoulder preoperatively. It is unknown how long the effect of BPO lasts. We evaluated C acnes counts 1 week after BPO application. We hypothesized that BPO would decrease C acnes burden with a rebound after 1 week. METHODS Screening of 102 healthy volunteers with no history of shoulder surgery or C acnes infection was performed to establish bacterial counts. Thirty-four participants were selected based on an established threshold. Each was given BPO 5% for 3 consecutive days of application on either the left or right shoulder as indicated by a random number generator. Deep sebaceous gland cultures were obtained with a detergent scrub technique before BPO application, after 3 days of use, and 1 week after BPO treatment commenced. RESULTS The differences between the logarithmic reduction and the logarithmic rebound at the anterior, lateral, and posterior sites were statistically significant. Anteriorly, the average log reduction was -0.44 and the average log rebound was 0.69 (P = .003). Laterally, reduction was -0.64 and rebound was 0.74 (P = .003). Posteriorly, reduction was -0.63 and rebound was 0.78 (P = .008). At the axilla, reduction was -0.40 and rebound was 0.31 (P = .10). The differences in C acnes burden between pretreatment and 1-week counts at all sites were not statistically significant. CONCLUSION A significant decrease in C acnes burden occurred after BPO application but was not permanent. Significant rebound occurred just 1 week later.
Journal of Bone and Mineral Research
Patients with Hutchinson-Gilford progeria syndrome (HGPS) have low bone mass and an atypical skel... more Patients with Hutchinson-Gilford progeria syndrome (HGPS) have low bone mass and an atypical skeletal geometry that manifests in a high risk of fractures. Using both in vitro and in vivo models of HGPS, we demonstrate that defects in the canonical WNT/b-catenin pathway, seemingly at the level of the efficiency of nuclear import of b-catenin, impair osteoblast differentiation and that restoring b-catenin activity rescues osteoblast differentiation and significantly improves bone mass. Specifically, we show that HGPS patientderived iPSCs display defects in osteoblast differentiation, characterized by a decreased alkaline phosphatase activity and mineralizing capacity. We demonstrate that the canonical WNT/b-catenin pathway, a major signaling cascade involved in skeletal homeostasis, is impaired by progerin, causing a reduction in the active b-catenin in the nucleus and thus decreased transcriptional activity, and its reciprocal cytoplasmic accumulation. Blocking farnesylation of progerin restores active b-catenin accumulation in the nucleus, increasing signaling, and ameliorates the defective osteogenesis. Moreover, in vivo analysis of the Zmpste24-/-HGPS mouse model demonstrates that treatment with a sclerostin-neutralizing antibody (SclAb), which targets an antagonist of canonical WNT/b-catenin signaling pathway, fully rescues the low bone mass phenotype to wild-type levels. Together, this study reveals that the b-catenin signaling cascade is a therapeutic target for restoring defective skeletal microarchitecture in HGPS.
The American journal of sports medicine, 2018
Massive rotator cuff tears (RCTs) begin as primary tendon injuries and cause a myriad of changes ... more Massive rotator cuff tears (RCTs) begin as primary tendon injuries and cause a myriad of changes in the muscle, including atrophy, fatty infiltration (FI), and fibrosis. However, it is unclear which changes are most closely associated with muscle function. To determine if FI of the supraspinatus muscle after acute RCT relates to short-term changes in muscle function. Controlled laboratory study. Unilateral RCTs were induced in female rabbits via tenotomy of the supraspinatus and infraspinatus. Maximal isometric force and rate of fatigue were measured in the supraspinatus in vivo at 6 and 12 weeks after tenotomy. Computed tomography scanning was performed, followed by histologic analysis of myofiber size, FI, and fibrosis. Tenotomy resulted in supraspinatus weakness, reduced myofiber size, FI, and fibrosis, but no differences were evident between 6 and 12 weeks after tenotomy except for increased collagen content at 12 weeks. FI was a predictor of supraspinatus weakness and was stron...
Journal of the Chinese Institute of Engineers
Abstract Recognizing 3‐D objects from 2‐D images has been an important area of research in comput... more Abstract Recognizing 3‐D objects from 2‐D images has been an important area of research in computer vision. In this paper, an efficient method is developed to determine the position and the orientation of a 3‐D polyhedron in a noisy image. This method assumes that the direction of a straight line on an image can be determined from noisy data. A set of linear equations are used to determine the orientation of an object. In cases where there are not enough straight lines of an image presented, the constraint equations can be introduced and the iterative process is applied. However the iterative process is simple and the divergence is not a problem. After the orientation is determined, the straight lines, corresponding to the visible edges of the object, are used to determine the intersection points. From the intersections and the corresponding corners of the polyhedron, another set of linear equations are used to obtain the position of the object. If the sum of the perpendicular distances, between the endpo...
Journal of the Chinese Institute of Engineers
Abstract In this paper, two methods, the Individual Calibration Method (ICM) and the Simultaneous... more Abstract In this paper, two methods, the Individual Calibration Method (ICM) and the Simultaneous Calibration Method (SCM), are used to calibrate a vision system with two cameras. The first approach calibrates a camera individually. For the second approach, two or more sets of camera intrinsic and extrinsic parameters are determined simultaneously such that the position errors for the 3‐D points are minimized. We show, theoretically and experimentally, the following results: (a) the offsets of the image centers do not affect significantly the position and orientation of a coordinate frame with respect to a stereo vision system with two cameras; (b) the lens distortion will not change dramatically the position and orientation of a coordinate frame with respect to a stereo vision system. We also find that (a) there is a difference in the determination of an object's location for the simultaneous and individual calibration methods; (b) the approach of calibrating two cameras simultaneously has the advantage ...
Journal of the Chinese Institute of Engineers
... Jim ZC Lai* and Shyh-Hwa Chyi Department of Information Engineering Feng Chia University Taic... more ... Jim ZC Lai* and Shyh-Hwa Chyi Department of Information Engineering Feng Chia University Taichung, Taiwan 40724, ROC ... The interpolated position points Page 3. JZC Lai & SH Chyi: A Parallel Algorithm for Generating Set Points in Cartesian Space for Spline Motion 41 Pi+1 ...
Journal of the Chinese Society of Mechanical Engineers Transactions of the Chinese Institute of Engineers Series C, 1992
Signal Processing, Apr 1, 2010
Pattern Recognition, Nov 1, 2009
In this paper, we present a fast k-means clustering algorithm (FKMCUCD) using the displacements o... more In this paper, we present a fast k-means clustering algorithm (FKMCUCD) using the displacements of cluster centers to reject unlikely candidates for a data point. The computing time of our proposed algorithm increases linearly with the data dimension d, whereas the computational complexity of major available kd-tree based algorithms increases exponentially with the value of d. Theoretical analysis shows that our method can reduce the computational complexity of full search by a factor of SF and SF is independent of vector dimension. The experimental results show that compared to full search, our proposed method can reduce computational complexity by a factor of 1.37-4.39 using the data set from six real images. Compared with the filtering algorithm, which is among the available best algorithms of k-means clustering, our algorithm can effectively reduce the computing time. It is noted that our proposed algorithm can generate the same clusters as that produced by hard k-means clustering. The superiority of our method is more remarkable when a larger data set with higher dimension is used.