Creat membership Creat membership
Sign in

Forgot password?

Confirm
  • Forgot password?
    Sign Up
  • Confirm
    Sign In
home > search

Now showing items 1 - 16 of 113

  • A LOW-PHASE-NOISE CMOS QUADRATURE VCO WITH PMOS BACK-GATE COUPLING

    Yeh, Mel-Ling   Lin, Yao-Chian   Liou, Wan-Rone   Kuo, Sheng-Hing   Roblin, Patrick   Chang, Chung Cheng  

    A new PMOS backgate quadrature voltage controlled oscillator (QVCO) is designed and implemented using TSMC 0.18 mu m 1P6M CMOS technology. The phase noise of the PMOS hack-gate coupled QVCO operating at 1.5 V is measured to be -100 dBc/Hz and -125.08 dBc/Hz at 100 KHz and 1 MHz offset, respectively, for a low power consumption of 15 mW. The backgate QVCO demonstrates a wide frequency tuning range, a low phase noise, and a low power consumption. The corresponding figure-of-merit of the QVCO is -186 dBc/Hz. (C) 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2682-2685, 2010: View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25564
    Download Collect
  • Associations between Water Quality Measures and Chronic Kidney Disease Prevalence in Taiwan.

    Chang, Kuan Y   Wu, I-Wen   Huang, Bo-Ruei   Juang, Jih-Gau   Wu, Jia-Chyi   Chang, Su-Wei   Chang, Chung Cheng  

    To determine the relationships between exposure to environmental contaminants in water and chronic kidney disease (CKD), we investigated the associations of 61 water attributes with the prevalence of CKD and End-Stage Renal Disease (ESRD) using data from 2005 to 2011 from all 22 counties and cities in the main island of Taiwan. We acquired patient information from the Taiwan Longitudinal Health Insurance Database to calculate the age-standardized CKD and ESRD prevalence rates and linked the patients' residences to the water quality monitoring data, which were sampled periodically for a total of over 45,000 observations obtained from the Taiwan Environmental Water Quality Information Database. The association analysis adjusting for gender, age, and annual effects showed that the zinc (Zn), ammonia, chemical oxygen demand (COD), and dissolved oxygen in rivers were weakly correlated with CKD (tau =3D 0.268/0.250/0.238/-0.267, p =3D 6.01*10-6/2.52*10-5/6.05*10-5/3.30*10-5, respectively), but none for ESRD. The importances of Zn and COD in rivers were also demonstrated in a CKD regression model. Moreover, an unusually high CKD prevalence was related to arsenic contamination in groundwater. A further prospective cohort study would improve our understanding of what level of environmental water with risky properties could affect the development of CKD.=20
    Download Collect
  • Fabrication and characterization of PZT thin film ultrasonic devices

    Chang, Chung Cheng   Chen, Kau Hsiung  

    Download Collect
  • Study of the fabrication of a silicon pressure sensor

    CHANG, CHUNG CHENG   LIEU, CHI TSAI   KUAN, MEI  

    Download Collect
  • The oscillation condition and optical detection of series photodetector frequency circuit system matched with PMMA

    Hsu, Yuh Ming   Chang, Chung Cheng  

    In this study, the oscillation conditions for series photodetector frequency circuit system were proposed and verified experimentally. The effect of the capacitance C-p and oscillator phase theta on the oscillation ability of series photodetector frequency circuit system was investigated. It revealed that series photodetector frequency circuit system possessed excellent oscillation ability, but the oscillation ability decreased with increasing oscillator phase or decreasing capacitance C-p, even resulted in a cease-to oscillate zone. Moreover, this study elucidated the frequency response and optical detection of series photodetector frequency circuit system matched with PMMA for fluorescence dye concentration. In accordance with Hex fluorescence dye concentrations and frequency responses, the detection limit of fluorescence dye concentration 3.3 pmol/L can be measured by 100 MHz sensor system matched with PMMA. The results also showed that the frequency shift of 100 MHz sensor system matched with PMMA was linearly related to the logarithm of fluorescence dye concentration from 3.3 pmol/L to 33.3 mu mol/L. (C) 2012 Published by Elsevier GmbH.
    Download Collect
  • Frequency sensitivity analysis of series photodetector frequency circuit system using circuit parameters of quartz crystal

    Hsu, Yuh Ming   Chang, Chung Cheng  

    The 48 MHz series photodetector frequency circuit systems matched with different quartz crystals were developed for frequency sensitivity analysis. In accordance with derived theory of series photodetector frequency circuit system, the circuit parameters of quartz crystal such as R-q and C-q can be applied to improve the frequency sensitivity. On the basis of parameter adjustment, the quartz crystal with proper R-q and C-q was selected to improve the frequency sensitivity of fluorescence detection. In the optimal conditions of R-q and C-q, the detection limit of U1392-Hex fluorescence dye concentration 3.3 pmol/L can be measured by 48 MHz sensor system. Moreover, the frequency method showed that the detection limit of U1392-Hex fluorescence dye concentration was lower than the conventional fluorescence technique by 2-3 orders. The result also indicated that the frequency shift Delta F was linearly related to the logarithm of fluorescence dye concentration in the range 3.3 pmol/L-3.3 mu mol/L. (C) 2012 Published by Elsevier GmbH.
    Download Collect
  • A study on the biological detection chip through the use of PDMS lens for the reinforcement of fluorescence receiving signal

    Chang, Chung Cheng   Hsu, Yuh Ming   Chen, Tai Chun   Ho, Chih Chieh   Te Chen, Chao   Chen, Po Tai  

    In this study, MEMS process technology is adopted to produce microfluidic chip and PDMS lens. SU-8 thick film photo resist is coated onto silicon wafer surface in two times of spin coating, then through lithography and mold transfer technology, PDMS chip of minimal line width 100 μm and thickness 200 μm is printed. In fluorescence detection aspect, we use objective lens to couple laser optical source to optical fiber, and then have it incident to excite fluorescence sample, the excited fluorescence then passes through filter and detected by optical detector of experiment group and spectrophotometer of reference group. From the experiment result, the Hex fluorescence detection limit of the system is verified to be 1 pmol/5 μl. In addition, we have integrated PDMS lens into microfluidic chip to make generalized detection experiment, it was found that the signal measured by optical embedded type is higher than that of non-embedded type. Meanwhile, the microfluidic chip with double concave lens (135°) and10 mm PDMS focusing lens can be utilized to obtain optimal fluorescence receiving effect. The fluorescence intensity is raised by 2-3 times, and the measurement limit is lowered to 100 fmol/5 μl.
    Download Collect
  • Improvement of frequency sensitivity of series photodetector frequency circuit system and its application for Cy5 fluorescence detection

    Hsu, Yuh Ming   Chang, Chung Cheng  

    This study elucidated the frequency characteristics of series photodetector frequency circuit system for detection of DNA probe ET996 marked with fluorescence dye Cy5. We developed 48 MHz series photodetector frequency circuit system with good sensitivity for fluorescence detection. In accordance with the theory of series photodetector frequency circuit system, the frequency sensitivity can be improved by adjusting circuit parameters such as A (tan theta). C(q), C(o), and C(p). In this research of A adjustment, the capacitance parameter C(m) of 48 MHz series photodetector frequency circuit system was adjusted to improve the frequency sensitivity for detection of fluorescence dye concentration; moreover, the bias of photodetector was also adjusted to improve the frequency sensitivity. In the optimal conditions of capacitance match and photodetector bias, the detection limit of ET996-Cy5 fluorescence dye concentration 2 pmol/L can be measured by 48 MHz sensor system. The results of fluorescence experiment also demonstrated that the frequency shift of 48 MHz sensor system was linearly related to the logarithm of fluorescence dye concentration from 200 nmol/L to 2 pmol/L. The frequency method can be applied simply and the detection limit of ET996-Cy5 fluorescence dye concentration was lower than the conventional fluorescence technique by 2 orders. (C) 2010 Elsevier GmbH. All rights reserved.
    Download Collect
  • A novel frequency method for quantitative analysis of fluorescence dye concentration by using series photodetector frequency circuit system

    Hsu, Yuh Ming   Chang, Chung Cheng  

    This study reported the frequency characteristics of series photodetector frequency circuit system for detection of fluorescence dye concentration. In the condition of the same fluorescence intensity, the series photodetector frequency circuit system with higher responsivity of photodetector had higher frequency shift. The 100 MHz series photodetector frequency circuit system was applied to determine the fluorescence dye concentration of HEX by frequency shift. The correlation curve showed that the frequency shift was linearly related to the logarithm of fluorescence dye concentration from 100 pmol 3 mu l(-1) to 10 amol 3 mu l(-1). The proposed method can be applied simply and the detection limit of fluorescence dye concentration was lower than the conventional fluorescence technique by 2-3 orders. (C) 2009 Elsevier B.V. All rights reserved.
    Download Collect
  • On the explicit analytic solution of ChengChang equation

    C. Wang   J.M. Zhu   S.J. Liao   I. Pop  

    An analytic technique is applied to solve the free convection over a heated horizontal flat surface embedded in a porous medium. An explicit, totally analytic and uniformly valid solution is given to the so-called Cheng-Chang equation, which agrees well with numerical results
    Download Collect
  • On the explicit analytic solution of ChengChang equation

    Wang, C.   Zhu, J.M.   Liao, S.J.   Pop, I.  

    An analytic technique is applied to solve the free convection over a heated horizontal flat surface embedded in a porous medium. An explicit, totally analytic and uniformly valid solution is given to the so-called ChengChang equation, which agrees well with numerical results.
    Download Collect
  • Analysis and improvement on frequency sensitivity of series photodetector frequency circuit system and its application for HEX fluorescence measurement

    Hsu, Yuh Ming   Chang, Chung Cheng  

    This study reported the improvement of frequency sensitivity of series photodetector frequency circuit system for fluorescence detection. The 48 MHz series photodetector frequency circuit system matched with polydimethyl siloxane (PDMS) focusing lens was applied to the detection of emissive fluorescence intensity. MEMS technology processes were used to fabricate PDMS focusing lens, the mixing amount of PDMS and the curing temperature were adjusted, and self-improved mold-transfer technology was used to make a 3D planar lens of diameter of 3 to 10 mm. While the series photodetector frequency circuit system matched with PDMS focusing lens of diameter 10 mm was used for fluorescence detection, the relative fluorescence intensity was enhanced by approximately two times, which indicated that the frequency sensitivity of the 48 MHz sensor system was improved. Besides, the bias of the photodetector was also adjusted to improve the frequency sensitivity. According to the optimal conditions of PDMS focusing lens and bias of a photodetector, the detection limit of HEX fluorescence dye concentration 3.3 pmol/L can be measured. The results of the fluorescence experiment also demonstrated that the frequency shift of the 48 MHz sensor system was linearly related to the logarithm of fluorescence dye concentration from 333.3 nmol/L to 3.3 pmol/L. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3567067]
    Download Collect
  • Tang Chung Chang (C. C. Tang): 1905-1993

    Robert L. Rausch  

    Download Collect
  • Joint venture fully acquired: Akzo Nobel gains control of Akzo Nobel Chang Cheng Coatings

    Download Collect
  • Joint venture fully acquired: Akzo Nobel gains control of Akzo Nobel Chang Cheng Coatings

    Download Collect
  • Vehicle Technology; Reports from National Chung Cheng University Describe Recent Advances in Vehicle Technology

    Download Collect
1 2 3 4 5 6 7 8

Contact

If you have any feedback, Please follow the official account to submit feedback.

Turn on your phone and scan

Submit Feedback