Papers by Author: Jui Chang Lin

Abstract: This research designs environment supervisory control system of computer room which consists of multiple Android environment controllers and one supervisory control server. An Android environment controller is a controller based on Android device. The controller contains an Android device, a Wi-Fi wireless access point, a switch hut (or NAT) and three data acquisition modules. The Android device enters TCP/IP LAN through the Wi-Fi access point. The data acquisition modules with TCP/IP interface are plugged into the LAN, and read/written by the Android device with Modbus TCP/IP protocol. Control logics are designed for computer room environment control. The controller monitors air conditioning systems, room temperature and humidity, fire alarm systems, uninterruptible power supply (UPS) systems, electricity supply systems, leak detections, and door access control systems. If something happens, it can drive buzzer, alarm, voice dialing, or air conditioning, send SMS, voice mail, record audio, or video. A supervisory control server is used to help remote controls of all Android environment controllers. All Android controllers send their operation data to the server. Authorized user can login to the server to monitor and control certain Android controller with a browser or Android device.

Abstract: In multi-wire flat rolling process, the error of the rolled wires in thickness was due to the roller deflection and the spring back of the rolled wire. In order to control the dimension accuracy, to know the quantity of thickness error precisely is very important. In this study, the DEFORM-3D finite element analysis software was used to simulate the multi-wire flat rolling process with the elastic-plastic deformation model, supposed the rollers as elastic body and the wires as elastic-plastic body through the rolling process. From the computer simulation results, it can be found that, the deflection of roller has the biggest effect on the dimension accuracy of wire. To control the deflection value of roller, besides roller material and the roller length, the choice of roller diameter is also very important.

Abstract: This article is pointed to the dimension accuracy analysis of the micro-punching mold for plastic carrier tape. The parts’ dimensions of the punch were first determined by the specification of the plastic carrier tape. The parts would be manufactured and assembled, and the performance of the punch was tested subsequently. Variation of dimensional accuracy of the plastic carrier tape was inspected to evaluate the performance of the punch. Mean and variance test was conducted under the significance level of α = 0.05. Through these inspections, all the plastic carrier tape met the specifications of dimensional accuracy, which indicated that the precision and performance of the developed micro-punching mold also met the requirement.

Abstract: This study is subject to 3D virtual simulation and experiment design method application in the optimal clearance design in the 3D shell punched processing. During the simulation stage, the PAM-CRASH and 3D-CAD (Pro/E) system are used to model the punching processing. The results of the punching maximum punched burr from the 3D virtual punching simulation were input to a neural network to establish a model corresponding to the 3D shell punched variables. Once the metal punching control parameters, such as punch/die radius, punch/die clearance, punch cutting angle and different material thickness, were given, the punching processing performance (the punching maximum burr and maximum stress) can be accurately predicted by this developed network. Therefore, in this research, a satisfactory result based on the simulation verification is established.

Abstract: This study aimed to create a multi-cavity and non-uniform thickness die casting for flowing balance. The die casting processes involved a hot-chamber die casting experiment and computer aided simulation to explore the flowing condition of the molten metal in the metal molding process. Computer-aided mould flow analysis software FLOW 3D V9.2 was applied to simulate the filling stage of zinc alloy in the mould cavities. The design parameters of the mould included four variables relating to the gate: width, position, shape, and thickness of cross-section. Analysis results shows that the primary goals of balance design include two things: (1) the flowing path of molten metal was shortest; (2) the mould cavity was easiest to fill with molten metal. The flowing balance design used analysis software to simulate the flowing condition of the air, which produced an air trap. The melting metal motive force pushed air into the slug well in order to reduce the production of pores. The experiment confirms the actual flowing situation of zinc alloy with a nearly 95% accuracy.

Abstract: This article is pointed to the dimension accuracy analysis of the vacuum forming mold for plastic carrier tape. The dimension accuracy of the vacuum forming mold was decided by the dimension specification of the plastic carrier tape. After detail design of the parts which would be manufactured and assembled. The accuracy and performance of the mold had been tested subsequently. The dimension accuracy of the mold was conducted by the accuracy of the plastic carrier tape. Variation of dimensional accuracy of the plastic carrier tape was inspected to evaluate the performance of the vacuum forming mold. Mean and variance test was conducted under the significance level of α = 0.05.Through series of inspections, all the plastic carrier tape met the specification of dimension accuracy which indicated that the precision and performance of the developed vacuum forming mold also met the requirement.

Abstract: Optically, humans can discriminate between colors as close as 2nm in wavelength in relative judgment task. However, there is little research to discuss color differences for absolute color judgments in which the comparison is held in memory. Therefore, the intent of this study was to explore effects of wavelengths on the Just Noticeable Difference (JND) of absolute judgments in our perceptual world. A color identification task was utilized to investigate the JND of wavelengths. In the experiment, the Standard Stimulus Color (SSC) and the Comparison Stimulus Color (CSC) were successively presented. The SSC which was presented first must be stored in working memory and recalled when the second color, CSC, is presented. Subjects had to decide if the CSC matched the SSC. Each CSC was presented four times for each subject in the experiment. The CSC wavelength that was recognized as different from the SSC twice was designed as a JND wavelength. Five SSC wavelengths with 100% saturation and 100% lightness were chosen from the hue circle of HLS color space which included 360 hues. Because the hue circle is a circle, the CSC may be on both sides of a SSC in the hue circle. The CSC hue which may be located on the clockwise direction or counter clockwise direction of the SSC was called clockwise direction color (CD) or counter clockwise direction color (CCD), respectively. The wavelengths expressed with HLS color space were translated into coordination of CIE1931 (x, y)-chromaticity diagram. The results indicated that threshold sensitivities varied for different wavelengths on absolute judgment tasks. The lights with longest or shortest wavelength had greater JNDs than ones with middle wavelengths for absolute judgment tasks. The comparison of the results of the experiment on absolute color judgment tasks and MacAdam’s (1942) findings for relative color judgment tasks were also discussed.

Abstract: Chips scraping each other during transportation, and chips coming into contact with water or air will cause oxidization resulting in poor quality products. The chips need to be well packed and to be protected from the environment. The method of Surface Mount Component (SMC) packing using plastic carrier tape can reduce chip damage. This study focuses on the extrusion process parameters optimization of plastic carrier tape. Because each extrusion process produces 270 pieces of carrier tape, the tape size is 1.35mmX2.25mmX1.35mm and is extremely difficult to reach the tolerance standard. This study utilized a practical test to explore various factors on the quality of the carrier tape, such as the rotational speed of extruder screw motor and extrusion mold; the negative pressure of extrusion mold; and the temperature of the extrusion mold. These experiments could find out an optimal extrusion process.

Abstract: This research applies 3D mesh mold-flow analysis to analyze the SD (Secure Digital) card. It aims at temperature of the mold and plastic. The proper mold filling temperature is found by simulation analysis to improve the short shot situation, and seeks the cause of warping via various processed conditions. SD memory card clip has a big variation in thickness. Due to the bigger flow resistance the plastic is difficult to reach thinner portion, even hot plastic is also difficult to supply. The temperature of plastic goes down as a result of the cold mold cavity. Thus, the plastic does not reach certain portions before solidifying. The cooling system of injection machine was controlled by constant temperature oil cooling. This study explored the optimum injection condition by utilizing experiment to control the temperature of the plastic, the temperature of mold, the packing pressure process and so on. It is valuable to companies which utilize injection mold applications.

Abstract: This research utilizes an image-vision-system to measure the size of the product-burr. The relational expression was established between the clearance of micro punching die and burr size after blanking the composite material via a neural network. This can help to anticipate the burr size under any clearance and used cycles of punching die. The purposes of this research are: (1) it can predict the used cycles of punching die at any clearance between the punch and die, the engineer can change the punching dies at right moment to prevent the bad product from producing; (2) it can utilize this research to find out the optimum clearance condition which can avoid bad design of the punching die, which will take long time to repaired the punching die.