Chien-Hung Chen

Automatic segmentation of abnormal cell nuclei from microscopic image analysis for cervical cancer screening

In this paper, two methods of microscopic image analysis were presented to classify the abnormal cells in Papanicolaou(Pap) smear for cervical cancer screening. Our goal is to extract those cell nuclei which are abnormally large size, bizarre shape as well as hyper density and we hope to apply this method to the different kinds of abnormal cells. The global information of the image and the local image condition were meantime considered. The reported method searched whole picture by scanning on different axes and determined the locations of abnormal cell nuclei with high contrast This developed method is also able to find cell nuclei, those were almost as bright as the background. Using the reported cytological image analysis, we successfully recognized the abnormal cells such as squamous intraepithelial neoplasia (SIL) and differentiated them from the normal epithelial cells.

Home self-monitoring of blood flow velocity based on LabVIEW mobile environment

In this study, we have presented the prototype of a wireless blood flow velocity monitoring environment that provides a home self-monitoring healthcare device for patients who need a long-term observation of peripheral blood flow dynamics. The self-monitoring device is able to measure blood flow velocity of cutaneous microvascular in vivo. The measurement system was integrated in the LabVIEW mobile environment that provide the data encode, data transmission via Bluetooth, and information display. The results of this study show the overall system function and the ability of blood flow velocity monitoring.

Preparation of Silicon Nanowire Field-effect Transistor for Chemical and Biosensing Applications

Surveillance using biomarkers is critical for the early detection, rapid intervention, and reduction in the incidence of diseases. In this study, we describe the preparation of polycrystalline silicon nanowire field-effect transistors (pSNWFETs) that serve as biosensing devices for biomarker detection. A protocol for chemical and biomolecular sensing by using pSNWFETs is presented. The pSNWFET device was demonstrated to be a promising transducer for real-time, label-free, and ultra-high-sensitivity biosensing applications. The source/drain channel conductivity of a pSNWFET is sensitive to changes in the environment around its silicon nanowire (SNW) surface. Thus, by immobilizing probes on the SNW surface, the pSNWFET can be used to detect various biotargets ranging from small molecules (dopamine) to macromolecules (DNA and proteins). Immobilizing a bioprobe on the SNW surface, which is a multistep procedure, is vital for determining the specificity of the biosensor. It is essential that every step of the immobilization procedure is correctly performed. We verified surface modifications by directly observing the shift in the electric properties of the pSNWFET following each modification step. Additionally, X-ray photoelectron spectroscopy was used to examine the surface composition following each modification. Finally, we demonstrated DNA sensing on the pSNWFET. This protocol provides step-by-step procedures for verifying bioprobe immobilization and subsequent DNA biosensing application.

An Integrated Embedded System for Evaluating Performance Parameters of CMOS Image Sensor

This paper introduces a CMOS-image-sensor-performance evaluation system that can compute parameters including pixelwise dynamic range, dynamic linearity, signal-to-noise ratio, and chip-level dynamic uniformity with a single measurement. The proposed system offers a simpler and significantly more integrated approach than the available systems by employing an embedded processing system and a large-data-processing method with multithreading capability. This paper also presents a new optimization technique to overcome the memory-size limitations of embedded systems for larger data-processing applications. The proposed system is designed and implemented to target small business applications and laboratories conducting research on CMOS quality sensors.

Implementation of a Large Data Processing Method for Embedded System and CMOS SNR Application

The embedded system is the future trends of instrument and the larger memory capacity of embedded system is favor to different variety of applications. The commercial embedded systems are always restricted by their embedded memory capacity and required to be upgraded, especially in image application. This article reports a new design and development of an embedded system built in a CMOS image SNR measurement instrument. The new developed approach using the mix technique of large data processing (MLDP) method for CMOS SNR calculation is described. The MLDP method uses an external memory device as auxiliary memory in the regular embedded system to break the memory capacity limitation. The experimental results show the new method is applied successfully in CMOS SNR measurement and the calculated speed is increased almost 200 times compared to that of the traditional method even thought the processing data size is over the embedded system memory.

A design of near infrared spectrometer for pears sugar concentration analysis

Non-destructive inspection is one of the important concerns to industry. There is the necessity of low-cost instrumentation for online rapid measurement and analysis of inner quality of fruit. This study is the development of a low-cost near IR inspection system based on flat field concave grating. This system is capable of quickly inspecting the sugar concentration of pears for fruit grade category. The proposed near IR inspection system was tested and the multivariate calibration technique, PLSR (partial least square regression) was introduced to analyze the reflected near IR spectra collected from the skin of pears. The results of experiments show the overall system performance and the ability of the prediction on sugar concentration of pears.

DESIGN OF AN AUTOMATED FEEDBACK CONTROL COOLING SYSTEM FOR SWIR LINEAR IMAGE SENSOR APPLICATION

Our novel automated feedback temperature controlled cooling system consists of a temperature measurement circuit, a TE cooler, a thermistor, a microcontroller, and a digital-to-analog converter and PWM algorithms. The measurement accuracy of this temperature controlled TE system was better than 0.1°C and can be used for maintaining an instruments isothermal applications. The experimental results of SWIR linear image shows that the temperature can be stably maintained at −20°C, the dark output current can be reduced almost 80 mV (Integration time: 100 ms) and the SNR of pixel can be improved from 48 dB to 83 dB as well.