Browsing by Author "Lin, Yu-Cheng"

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A Collaborative and Ubiquitous System for Fabricating Dental Parts Using 3D Printing Technologies
(2019-09-01)
Wang, Yu-Cheng
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Chen, Toly
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Lin, Yu-Cheng
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工業工程與管理學系
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Department of Industrial Engineering and Management
Three-dimensional (3D) printing has great potential for establishing a ubiquitous service in the medical industry. However, the planning, optimization, and control of a ubiquitous 3D printing network have not been sufficiently discussed. Therefore, this study established a collaborative and ubiquitous system for making dental parts using 3D printing. The collaborative and ubiquitous system split an order for the 3D printing facilities to fulfill the order collaboratively and forms a delivery plan to pick up the 3D objects. To optimize the performance of the two tasks, a mixed-integer linear programming (MILP) model and a mixed-integer quadratic programming (MIQP) model are proposed, respectively. In addition, slack information is derived and provided to each 3D printing facility so that it can determine the feasibility of resuming the same 3D printing process locally from the beginning without violating the optimality of the original printing and delivery plan. Further, more slack is gained by considering the chain effect between two successive 3D printing facilities. The effectiveness of the collaborative and ubiquitous system was validated using a regional experiment in Taichung City, Taiwan. Compared with two existing methods, the collaborative and ubiquitous 3D printing network reduced the manufacturing lead time by 45% on average. Furthermore, with the slack information, a 3D printing facility could make an independent decision about the feasibility of resuming the same 3D printing process locally from the beginning.
A Fuzzy Collaborative Approach for Evaluating the Suitability of a Smart Health Practice
(2019-12-01)
Chen, Tin-Chih Toly
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Wang, Yu-Cheng
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Lin, Yu-Cheng
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Wu, Hsin-Chieh
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Lin, Hai-Fen
A fuzzy collaborative approach is proposed in this study to assess the suitability of a smart health practice, which is a challenging task, as the participating decision makers may not reach a consensus. In the fuzzy collaborative approach, each decision maker first applies the alpha-cut operations method to derive the fuzzy weights of the criteria. Then, fuzzy intersection is applied to aggregate the fuzzy weights derived by all decision makers to measure the prior consensus among them. The fuzzy intersection results are then presented to the decision makers so that they can subjectively modify the pairwise comparison results to bring them closer to the fuzzy intersection results. Thereafter, the consensus among decision makers is again measured. The collaboration process will stop when no more modifications are made by any decision maker. Finally, the fuzzy weighted mean-centroid defuzzification method is applied to assess the suitability of a smart health practice. The fuzzy collaborative approach and some existing methods have been applied to assess the suitabilities of eleven smart health practices for a comparison. Among the compared practices, only the fuzzy collaborative approach could guarantee the existence of a full consensus among decision makers after the collaboration process, i.e., that the assessment results were acceptable to all decision makers.
A fuzzy polynomial fitting and mathematical programming approach for enhancing the accuracy and precision of productivity forecasting
(2019-06-01)
Chen, Toly
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Ou, Chungwei
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Lin, Yu-Cheng
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工業工程與管理學系
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Department of Industrial Engineering and Management
Forecasting future productivity is a critical task to every organization. However, the existing methods for productivity forecasting have two problems. First, the logarithmic or log-sigmoid value, rather than the original value, of productivity is dealt with. Second, the objective functions are not consistent with those adopted in practice. To address these problems, a fuzzy polynomial fitting and mathematical programming (FPF-MP) approach are proposed in this study. The FPF-MP approach solves two polynomial programming problems, based on the original value of productivity, in two steps to optimize accuracy and precision of forecasting future productivity, respectively. A real case was adopted to validate the effectiveness of the proposed methodology. According to the experimental results, the proposed FPF-MP approach outperformed six existing methods in improving the forecasting accuracy and precision.
A multibelief analytic hierarchy process and nonlinear programming approach for diversifying product designs: Smart backpack design as an example
(1970-01-01)
Lin, Yu-Cheng
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Chen, Toly
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工業工程與管理學系
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Department of Industrial Engineering and Management
Owing to the cost constraint, it is difficult to incorporate all critical features into a single product design. To deal with this issue, analytic hierarchy process is a well-known method that compares the relative priorities of critical features. This study aims to illustrate that the judgment of a designer can be used to generate multiple diversified product designs. To this end, this study proposed a multibelief analytic hierarchy process and nonlinear programming approach. In the proposed methodology, a decision maker's judgment matrix is decomposed into several single-belief judgment matrices that are more consistent than the original judgment matrix and represent diversified points of view regarding the relative priorities of factors. To this end, a nonlinear programming model is established and optimized. The proposed methodology was applied to a smart backpack design problem. It was concluded that a designer's judgment was often inconsistent, which was ignored in the conventional analytic hierarchy process method but could be employed to diversify product designs.
A Novel Seesaw Swivel Actuator Design and Fabrication
(2010-07-01)
Chou, Po-Chien
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Lin, Yu-Cheng
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Cheng, Stone
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機械工程學系
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Department of Mechanical Engineering
Many small form factor optical pickup heads based on the swing arm design utilize piezoelectricity or slim plate of metal to perform focusing action. The seesaw type actuator is a new driving mechanism used for swiveling the entire optical pickup heads devices. The configuration of the seesaw swivel actuator has unique features including a rotary actuator for coarse and fine tracking and a seesaw arm for swiveling along a pivot instead of a hinge to permit a tilt focus movement. In this paper, a biaxial voice coil motor (VCM) combining the swing type tracking VCM and seesaw type focusing VCM in the rear of the swing arm is proposed. This seesaw swing arm actuator is fabricated and evaluated in dynamic experiments. The performance of the biaxial VCM is verified through simulation by finite-element methods, and the effectiveness is confirmed by experimental procedures and parametric design optimization.
A three-dimensional-printing-based agile and ubiquitous additive manufacturing system
(2019-02-01)
Chen, Tin-Chih Toly
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Lin, Yu-Cheng
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工業工程與管理學系
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Department of Industrial Engineering and Management
Mass producing items using three-dimensional (3D) printing is challenging. This study exploits this technology for mass production by developing an agile and ubiquitous additive manufacturing system based on 3D printing. The proposed system receives an order and then distributes the order among multiple 3D printing facilities to minimize the makespan (i.e., cycle time). A decision-making model was also constructed for distributing the order to multiple 3D printing facilities to minimize the makespan, and an algorithm was developed to solve the model. The effectiveness of the proposed methodology was evaluated through an experiment. The experimental results showed that the proposed methodology reduced the cycle time by 54 min on average. Additionally, it could also distribute orders and balance the workloads of multiple 3D printing facilities. The proposed system is an industrial Internet of things based technology that coordinates multiple distributed 3D printing facilities via the Internet. Its application to the mass production of 3D-printed items is efficient and economical.
Achieving high focusing power for a large-aperture liquid crystal lens with novel hole-and-ring electrodes
(2008-11-10)
Chiu, Chi-Wei
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Lin, Yu-Cheng
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Chao, Paul C. -P.
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Fuh, Andy Y. -G.
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電控工程研究所
Aiming to equip commercial camera modules, such as the optical imaging systems with a CMOS sensor module in 3 Mega pixels, an ultra thin liquid crystal lens with designed hole-and-ring electrodes is proposed in this study to achieve high focusing power. The LC lens with proposed electrodes improves the central intensity of electric field which leads to better focusing quality. The overall thickness of the LC lens can be as thin as 1.2 mm and the shortest focal length of the 4 mm-aperture lens occurs at 20 cm under an applied voltage of 30 V at 1 KHz. The inner ring electrode requires only 40% of applied voltage of the external hole electrode. The applied voltages for this internal ring and external hole electrodes can simply be realized by a pre-designed parallel resistance pair and a single voltage source. Experiments are conducted for validation and it shows that the designed LC lens owns good image clearness and contrast at the focal plane. The proposed design reduces the thickness of LC lens and is capable of achieving relative higher focusing power than past studies with lower applied voltage. (C) 2008 Optical Society of America
An advanced fuzzy collaborative intelligence approach for fitting the uncertain unit cost learning process
(2019-10-01)
Lin, Yu-Cheng
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Chen, Toly
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交大名義發表
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National Chiao Tung University
Estimating the unit cost of each product precisely and accurately is a prerequisite to determining the profitability of a manufacturer, which is usually addressed by fitting the underlying learning process. However, existing methods for this purpose often deal with a logarithmic or log-sigmoid value, rather than the original value, of the unit cost. To resolve this problem, in this study, a new fuzzy collaborative intelligence (FCI) approach is proposed by considering the original value of the unit cost directly. The effectiveness of the new FCI approach is validated with a real dynamic random access memory (DRAM) case. The experimental results showed that the new FCI approach outperformed two existing methods in improving the fitting accuracy in terms of MAE and MAPE and also in reducing the average range of the fitted unit costs.
Approximating alpha-cut operations approach for effective and efficient fuzzy analytic hierarchy process analysis
(2019-12-01)
Chen, Toly
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Lin, Yu-Cheng
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Chiu, Min-Chi
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工業工程與管理學系
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Department of Industrial Engineering and Management
Fuzzy analytic hierarchy process (FAHP) has been widely applied to multicriteria decision making (MCDM). However, deriving the fuzzy maximal eigenvalue and eigenvector of a fuzzy pairwise comparison matrix is a computationally intensive task. As a result, most existing FAHP methods estimate, rather than derive, the fuzzy maximal eigenvalue and weights. Therefore, the results are inaccurate. By contrast, the alpha-cut operations (ACO) method derives the fuzzy maximal eigenvalue and weights, but is time-consuming. To address these issues, the approximating alpha-cut operations (xACO) approach is proposed in this study. The proposed xACO approach does not enumerate all possible combinations of the a cuts of fuzzy pairwise comparison results, but approximates the membership functions of the fuzzy maximal eigenvalue and weights with logarithmic functions in the process. To evaluate the performance of the xACO approach, it was applied to two real cases. According to the experimental results, the xACO approach estimated the fuzzy maximal eigenvalue and weights effectively and efficiently based on less than 0.2% of the entire results. (C) 2019 Elsevier B.V. All rights reserved.
Calcium alginate microcapsule generation on a microfluidic system fabricated using the optical disk process
(2007-08-01)
Huang, Keng-Shiang
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Liu, Ming-Kai
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Wu, Chun-Han
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Yen, Yu-Tang
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Lin, Yu-Cheng
This paper describes the generation of monodisperse calcium alginate (Ca-alginate) microcapsules on a microfluidic platform using the commercial optical disk process. Our strategy is based on combining the rapid injection molding process for a cross-junction microchannel with the sheath focusing effect to form uniform water-in-oil (w/o) emulsions. These emulsions, consisting of 1.5% (w/v) sodium alginate (Na-alginate), are then dripped into a solution containing 20% (w/v) calcium chloride (CaCl2) creating Ca-alginate microparticles in an efficient manner. This paper demonstrates that the size of Ca-alginate microparticles can be controlled from 20 mu m to 50 mu m in diameter with a variation of less than 10%, simply by altering the relative sheath/sample flow rate ratio. Experimental data show that for a given fixed dispersed phase flow (sample flow), the emulsion size decreases as the average flow rate of the continuous phase flow (sheath flow) increases. The proposed microfluidic platform is capable of generating relatively uniform emulsions and has the advantages of active control of the emulsion diameter, a simple and low cost process and a high throughput.
Effectiveness of holographic optical element module sensor in measuring blood prothrombin time
(2014-07-01)
Lin, Yu-Cheng
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Yen, Shih-Chieh
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Cheng, Stone
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Huang, Tony
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機械工程學系
A small-form-factor holographic optical element (HOE) module, which was mounted on a dual-stage seesaw actuator, was utilized to evaluate blood coagulation in real time. The method involved assessing the decrease in transmitted light of the blood sample surface when the clotting is formed. The prothrombin time (PT) was measured by illumining and focusing a 635 nm laser beam onto the sample. As the fibrinogen turned into non-solute fibrin, the transmitted efficiency and total intensity of the reflected light from the reflector changed. A low-pass filter suppressed the noise in the coagulation-related transient response to yield accurate signals. Finally, the PT measurements were compared to those made classically using other optical sensors.
Effectiveness of holographic optical element module sensor in measuring blood prothrombin time
(2014-07-01)
Lin, Yu-Cheng
;
Yen, Shih-Chieh
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Cheng, Stone
;
Huang, Tony
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機械工程學系
A small-form-factor holographic optical element (HOE) module, which was mounted on a dual-stage seesaw actuator, was utilized to evaluate blood coagulation in real time. The method involved assessing the decrease in transmitted light of the blood sample surface when the clotting is formed. The prothrombin time (PT) was measured by illumining and focusing a 635 nm laser beam onto the sample. As the fibrinogen turned into non-solute fibrin, the transmitted efficiency and total intensity of the reflected light from the reflector changed. A low-pass filter suppressed the noise in the coagulation-related transient response to yield accurate signals. Finally, the PT measurements were compared to those made classically using other optical sensors.
Enhancement of Optical Adaptive Sensing by Using a Dual-Stage Seesaw-Swivel Actuator with a Tunable Vibration Absorber
(2011-05-01)
Chou, Po-Chien
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Lin, Yu-Cheng
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Cheng, Stone
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機械工程學系
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Department of Mechanical Engineering
Technological obstacles to the use of rotary-type swing arm actuators to actuate optical pickup modules in small-form-factor (SFF) disk drives stem from a hinge's skewed actuation, subsequently inducing off-axis aberrations and deteriorating optical quality. This work describes a dual-stage seesaw-swivel actuator for optical pickup actuation. A triple-layered bimorph bender made of piezoelectric materials (PZTs) is connected to the suspension of the pickup head, while the tunable vibration absorber (TVA) unit is mounted on the seesaw swing arm to offer a balanced force to reduce vibrations in a focusing direction. Both PZT and TVA are designed to satisfy stable focusing operation operational requirements and compensate for the tilt angle or deformation of a disc. Finally, simulation results verify the performance of the dual-stage seesaw-swivel actuator, along with experimental procedures and parametric design optimization confirming the effectiveness of the proposed system.
Enhancement of PZT embedded swing arm actuator using integrated read/write performance and actuation
(2012-04-01)
Lin, Yu-Cheng
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Chou, Po-Chien
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Cheng, Stone
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機械工程學系
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Department of Mechanical Engineering
The current technological challenges associated with the rotary-type seesaw arm actuator for small-form-factor (SFF) disk drives are the small skew focusing, which causes off-axis aberrations and reduces optical quality. This article develops a novel design for a seesaw arm actuator and suspension assembly that is based on a micro-PZT actuator to position pickup head. Dual-stage actuation relaxes the dynamic requirement on the focusing stroke. The proposed actuator with a tilt-compensation mechanism uses a PZT bender to drive pickup head focusing. This combined system, optical module and dual stage actuator, is effectively self-aligned the optical axis for read/write performance in both experiment and simulation result. Finite element modeling and dynamic measurements reveal significant improvements in the actuator bandwidth with and without micro-PZT actuator compensation.
Evaluating the Suitability of a Smart Technology Application for Fall Detection Using a Fuzzy Collaborative Intelligence Approach
(2019-11-01)
Lin, Yu-Cheng
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Wang, Yu-Cheng
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Chen, Tin-Chih Toly
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Lin, Hai-Fen
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工業工程與管理學系
Fall detection is a critical task in an aging society. To fulfill this task, smart technology applications have great potential. However, it is not easy to choose a suitable smart technology application for fall detection. To address this issue, a fuzzy collaborative intelligence approach is proposed in this study. In the fuzzy collaborative intelligence approach, alpha-cut operations are applied to derive the fuzzy weights of criteria for each decision maker. Then, fuzzy intersection is applied to aggregate the fuzzy weights derived by all decision makers. Subsequently, the fuzzy technique for order preference by similarity to the ideal solution is applied to assess the suitability of a smart technology application for fall detection. The fuzzy collaborative intelligence approach is a posterior-aggregation method that guarantees a consensus exists among decision makers. After applying the fuzzy collaborative intelligence approach to assess the suitabilities of four existing smart technology applications for fall detection, the most and least suitable smart technology applications were smart carpet and smart cane, respectively. In addition, the ranking result using the proposed methodology was somewhat different from those using three existing methods.
Feasibility Evaluation and Optimization of a Smart Manufacturing System Based on 3D Printing: A Review
(2017-04-01)
Chen, Toly
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Lin, Yu-Cheng
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工業工程與管理學系
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Department of Industrial Engineering and Management
As a major enabling factor for Industry 4.0, three-dimensional ( 3D) printing faces technical and managerial concerns that may hinder its sustainable development. In this study, four technical challenges are reviewed as follows: time-consuming 3D object design, limited types of usable materials, low precision, and low productivity. Seven managerial concerns are also discussed as follows: 3D object database management, intellectual property rights of 3D printing, business innovation, ubiquitous manufacturing, lean manufacturing, globalization and deglobalization, and feasibility evaluation and optimization. Then, this study asserts that technical challenges should be addressed to ensure the feasibility of a 3D printing application in a manufacturing context, whereas managerial concerns should be addressed to advance and optimize a 3D printing application. Based on the discussion, to maximize profit, a smart manufacturing system based on 3D printing should continually provide 3D objects of interest to customers, or join as many ubiquitous manufacturing networks as possible.(C) 2016 Wiley Periodicals, Inc.
Integer nonlinear programming and optimized weighted-average approach for mobile hotel recommendation by considering travelers' unknown preferences
(2018-10-01)
Lin, Yu-Cheng
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Chen, Toly
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Wang, Li-Chih
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工業工程與管理學系
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Department of Industrial Engineering and Management
The existing mobile hotel recommendation systems are usually subject to a difficult problem-travelers choose dominated hotels. This problem is difficult to resolve because there is no reason to recommend a hotel that is inferior to another in all aspects. To address this problem, an artificial dimension is added to each hotel to model unknown personal preferences. The possible values along the artificial dimension and the weight associated with it are derived by solving an integer nonlinear programming problem. Thus, the proposed methodology hybridizes objective and subjective weights. An illustrative example is provided to show the applicability of the proposed methodology. In addition, a field study was conducted in a small region of Seatwen District, Taichung City, Taiwan to evaluate the possible advantages of the proposed methodology over existing methods. The experimental results showed that the proposed methodology outperformed five existing methods in improving the successful recommendation rate, with the most significant advantage being up to 33 %. Furthermore, the recommendation results generated using the proposed methodology were found to be less risky.
Miniaturized suspension structure for precise flying height positioning measurement using a swing arm actuator with a holographic optical element module sensor
(2011-03-01)
Chou, Po-Chien
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Lin, Yu-Cheng
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Cheng, Stone
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機械工程學系
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Department of Mechanical Engineering
This work presents a means of active actuation of the suspension structure with a holographic optical element (HOE) for the small-form-factor optical-disk drives. The proposed HOE module sensor is mounted on a swing arm swivel-drive mechanism with unique features, including a rotary actuator for tracking and a swing arm nutates along a pivot for focusing. The fabrication methodology for a cantilever-beam-like structure with HOE module sensor is investigated. Furthermore, the performances of optical module with swing arm-swivel actuation are experimentally evaluated to demonstrate the effectiveness of precise flying height positioning measurement method. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3549259]
Multi-layer Rectangular/Non-Rectangular Obstacles-Avoiding X-Architecture Router
(2008)
Lin, Yu-Cheng
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Shi, Chia-Cheng
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Chen, Hung-Ming
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電機學院
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College of Electrical and Computer Engineering
Due to emerging DSM effects, routing has been a very important topic in cut-rent design flow. Currently there are three issues. One, the traditional Manhattan routing has longer length and larger delay than X-architecture routing. Second, in multilayer routing, the delay of one via is much larger than the delay of Manhattan routing. Third, since a routed segment and macro cell should be considered as obstacles, we must consider the rectangle and non-rectangle obstacles, and consider the number of vias as well. In this paper, under the conditions of rectangle obstacles and non-rectangle obstacles, we use fewer vias and X-Architecture router by region to construct the multilayer routing trees. The main purpose is to obtain a routing tree of minimal wirelength and minimal delay.
Nonconfocal Differential Interferometry Sensing Scheme for Scanning Probe Microscopy
(2011-04-01)
Lin, Yu-Cheng
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Cheng, Stone
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機械工程學系
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Department of Mechanical Engineering
In this work, we describe a nonconfocal differential interferometer to detect the cantilever vibration for a scanning probe microscope. Capable of focusing the beams on the different height surfaces of a cantilever to adapt the length of commercially available cantilever chips, the proposed two-beam interferometer can maintain the sensitivity by placing a glass slip for an object beam to extend the focal length to the cantilever. An experiment involving a scanning force microscope is performed in static mode operation for applications where topography and magnetic images are presented. (C) 2011 The Japan Society of Applied Physics