Shi-Ming Zhang

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BACKGROUND Human papilloma virus (HPV) infection was the main cause of cervical cancer. There were only a few reports and detailed data about epidemiological research of HPV infection in rural population of China. MATERIALS AND METHODS The cervical cells of rural Chaozhou women were collected, and multiplex real time PCR was firstly performed to detect(More)
—This paper demonstrates a predictive noise parameter estimation methodology for UHV/CVD SiGe HBT's which combines ac measurement, calibrated ac simulation and two of the latest Y-parameter-based noise models: 1) the thermody-namic noise model, and 2) the SPICE noise model. The bias current and frequency dependence of the minimum noise figure, the optimum(More)
—This paper investigates SiGe profile design tradeoffs for low-noise RF applications at a given technology generation (i.e., fixed minimum feature size and thermal cycle). An intuitive model relating structural parameters and biases to noise parameters is used to identify the noise limiting factors in a given technology. The noise performance can be(More)
—This paper presents measurements of the avalanche multiplication factor (M 0 1) in SiGe HBT's using a new technique capable of separating the avalanche multiplication and Early effect contributions to the increase of collector current with collector-base bias, as well as allowing safe measurements at practical current densities. The impact of collector(More)
We propose a new approach to clustering high dimensional data based on a novel notion of cluster cores, instead of on nearest neighbors. A cluster core is a fairly dense group with a maximal number of pairwise similar objects. It represents the core of a cluster, as all objects in a cluster are with a great degree attracted to it. As a result, building(More)
—A unified approach to RF and microwave noise parameter modeling in bipolar transistors is presented. Circuit level noise parameters including the minimum noise figure, the optimum generator admittance, and the noise resistance are analytically linked to the fundamental noise sources and the y-parameters of the transistor through circuit analysis of the(More)
—We present the first systematic experimental and modeling results of noise corner frequency () and noise corner frequency to cutoff frequency ratio () for SiGe hetero-junction bipolar transistors (HBTs) in a commercial SiGe RF technology. The and ratio are investigated as a function of operating collector current density, SiGe profile, breakdown voltage,(More)
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