Browsing by Author "Chang, Chun-Hao"

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Aquifer Parameter Estimation for a Constant-Flux Test Performed in a Radial Two-Zone Aquifer
(2009-09-01)
Yeh, Hund-Der
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Chang, Chun-Hao
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Chen, Yen-Ju
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環境工程研究所
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Institute of Environmental Engineering
A patchy aquifer or an aquifer with a finite thickness skin can be considered as a radial two-zone aquifer system, which can be characterized by five parameters, i.e., the thickness of the first zone and four aquifer parameters including the transmissivity and storage coefficient for each of the first and second zones. This paper proposes an approach based on an analytical solution of a constant-flux pumping in a confined two-zone aquifer and the simulated annealing algorithm to determine the five parameters simultaneously. The estimated results for the five parameters are fairly good even assuming the aquifer as a single-zone system at the beginning of the data analysis. The estimated results indicate that the first-zone parameters are much more difficult to accurately identify than the second-zone parameters due to insufficient early-time data and high correlation of the sensitivities among the first-zone parameters. However, the problem of inaccurate results obtained at the first-zone can be significantly improved if more densely temporal drawdown measurements are used.
Demo: Tagging IoT Data in a Drone View
(2019-01-01)
Van, Lan-Da
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Chang, Chun-Hao
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Tong, Kit-Lun
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Wu, Kun-Ru
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Zhang, Ling-Yan
Both cameras and IoT devices have their particular capabilities in tracking moving objects. Their correlations are, however, unclear. In this work, we consider using a drone to track ground objects. We demonstrate how to retrieve IoT data from devices, which are attached on human objects, and correctly tag them on the human objects captured by a drone view. This is the first work correlating IoT data and computer vision from a drone camera. Potential applications of this work include aerial surveillance, people tracking, and intelligent human-drone interaction.
Design and Implementation of a Packet-in Buffer System for SDN Switches
(2017-01-01)
Wang, Shie-Yuan
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Chang, Chun-Hao
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Hsieh, Yi-Hsuan
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Chou, Chih-Liang
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資訊工程學系
In this paper, we designed, implemented, and evaluated the performance of a Packet-in packet buffer system in an SDN bare metal commodity switch and Open vSwitch. In our approach, only the first packet of a new flow needs to be sent to the SDN controller via a Packet-in packet and all subsequent packets can be temporarily stored in the Packet-in packet buffer system until the arrival of the flow rule. Our experimental results show that our approach effectively prevents packets of a new flow from being dropped when they pass an SDN switch, significantly reduces the switch CPU usage, greatly reduces the control plane bandwidth usage, and greatly reduces the Packet-in packet processing load imposed on the SDN controller.
Hand-powered centrifugal microfluidic disc with magnetic chitosan bead-based ELISA for antibody quantitation
(2020-08-01)
Lin, Chia-Tung
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Kuo, Shao-Hsuan
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Lin, Pei-Heng
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Chiang, Pei-Huan
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Lin, Wan-Hsuan
Extreme point-of-care testing (POCT) is a medical test performed at or near patients at a resource-limited condition. POCT technology has advantages over traditional medical lab tests for molecular detection and infection diagnosis, such as being simple, portable, low-cost, and user-friendly. However, some POCT devices might rely on bulky equipment, and some might be easily influenced by components in biofluid, which might result in higher prices and lower accuracy. In this paper, we demonstrated a low-cost method for detecting bacterial infection in the early stage. We designed a hand-powered centrifugal microfluidic (CMF) disc with magnetic chitosan beads (MCBs) to detect specific circulating antibodies in human whole blood. Nine identical units was used for calibration curve plotting and sample testing. The MCBs, generated with another microfluidic chip and coated with MBL proteins (biomarker of drug-resistant Streptococcus pneumoniae, DRSP, taken as an example for bacterial infection), were served as the substrate of sandwich-structured enzyme-linked immunosorbent assays (ELISA) and as the micro stirring sphere at the same time. The limit of detection (LOD) in PBS and human whole blood were 22.67 ng/mL and 24.83 ng/mL, respectively. The comparison between calibration curves from the antibody spiked in human whole blood and that in PBS was shown to prove the high compatibility and low interference of biofluid, and the recovery rate was 92 %. In conclusion, since our low-cost, time-saving, and user-friendly hand-powered CMF device with minimally consumed electricity detected the target antibody precisely, we believe that other similar assays would be feasible as well. Therefore, we are firmly convinced that this alternative POCT device may lead to the development of next-generation healthcare diagnoses.
MONOLITHIC NI-ELECTROPLATED MICROSTRUCTURE AND ITS APPLICATION IN MICRO MIRRORS AND MICRO ASSEMBLY
(2014-01-01)
Chiu, Yi
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Lai, Wen-Ching
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Chang, Chun-Hao
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Chang, Chun-Po
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Chen, Ching-Hung
This paper presents micro mirrors and micro assembly mechanisms fabricated by monolithic nickel electroplating. Multiple nickel structural layers were electroplated and patterned with copper as the sacrificial material. A novel side latch design was proposed and demonstrated for 3D micro assembly of micro mirrors by simple push operation of micro probes. Micro mirrors was assembled in about 15 sec in laboratory tests. The resonance frequency of the scanning mode of a stand-alone micro mirror was measured to be 4.753 kHz with a quality factor of about 470.
PlantTalk: A Smartphone-Based Intelligent Hydroponic Plant Box
(2019-04-02)
Van, Lan-Da
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Lin, Yi-Bing
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Wu, Tsung-Han
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Lin, Yun-Wei
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Peng, Syuan-Ru
This paper proposes an IoT-based intelligent hydroponic plant factory solution called PlantTalk. The novelty of our approach is that the PlantTalk intelligence can be built through an arbitrary smartphone. We show that PlantTalk can flexibly configure the connections of various plant sensors and actuators through a smartphone. One can also conveniently write Python programs for plant-care intelligence through the smart phone. The developed plant-care intelligence includes automatic LED lighting, water spray, water pump and so on. As an example, we show that the PlantTalk intelligence effectively lowers the CO2 concentration, and the reduction speed is 53% faster than a traditional plant system. PlantTalk has been extended for a plant factory called AgriTalk.
Rapid and Safe Isolation of Human Peripheral Blood B and T Lymphocytes through Spiral Microfluidic Channels
(2019-05-31)
Chiu, Po-Lin
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Chang, Chun-Hao
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Lin, Yu-Ling
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Tsou, Ping-Hsien
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Li, Bor-Ran
Peripheral blood lymphocytes (PBLs) are mature lymphocytes that circulate in the blood rather than being localized to organs. A reliable label-free collection approach that can viably and appropriately isolate PBLs to establish in vitro culture systems is crucial for basic research and clinical requirements. However, isolation of PBLs from whole blood is difficult, and so the development of a rapid and safe method to perform this task is required. Microfluidic technology offers opportunities that challenge the performance of macroscale methods. In this study, we proposed a simple spiral microfluidic chip for efficient and high-throughput isolation of lymphocytes from a sample with prelysed RBCs. This spiral microfluidic platform does not rely on antibodies or biological markers for labeling cells of interest while isolating lymphocytes but rather enriches B and T lymphocytes through the different physical properties that are intrinsic to lymphocytes and other blood cells. The device was used to achieve high-throughput (similar to 1.3 x 10(5) cells/min) separation of lymphocytes with high viability (>95%). Compared with previous approaches, our device provided rapid, label-free, high-throughput, and safe lymphocyte separation.