This paper describes an efficient object-based hybrid image coding (OB-HIC) scheme. The proposed scheme is based on using the discrete wavelet transform (DWT) in conjunction with the discrete cosine transform (DCT) to provide coding performance superior to the popular image coders. The proposed method uses combination of the object-based DCT coding and the high performance of the set partitioning in hierarchical tree (SPIHT) coding. The subband image data in the wavelet domain is modified based on the DCT and the object classification of the coefficient in the low-frequency image subband (LL). The modification process provides a new subband image data containing almost the same information of the original one but having smaller values of the wavelet coefficients. Simulation results of the proposed method demonstrate that, with small addition in the computational complexity of the coding process, the peak signal-to-noise ratio (PSNR) performance of the proposed algorithm is much higher than that of the SPIHT test coder and some of famous image coding techniques.

Estrogen is a key hormone in human reproductive physiology, controlling ovulation and secondary sexual characteristics. In addition, it plays an important role in the pathogenesis of breast cancer. Indeed, estrogen receptor antagonists and aromatase inhibitors (which block estrogen biosynthesis) are primary drugs used for treatment and prevention in at-risk populations. Despite its importance, tissue concentrations of estrogen are not routinely measured because conventional techniques require large samples of biopsies for analysis. In response to this need, we have developed a digital microfluidic method and applied it to the extraction and quantification of estrogen in 1 microliter samples of breast tissue homogenate (as would be collected with fine-needle aspiration), as well as in whole blood and serum. This method may be broadly applicable to conditions requiring frequent analysis of hormones in clinical samples (for example, infertility and cancer).

Estrogen is a key hormone in human reproductive physiology, controlling ovulation and secondary sexual characteristics. In addition, it plays an important role in the pathogenesis of breast cancer. Indeed, estrogen receptor antagonists and aromatase inhibitors (which block estrogen biosynthesis) are primary drugs used for treatment and prevention in at-risk populations. Despite its importance, tissue concentrations of estrogen are not routinely measured because conventional techniques require large samples of biopsies for analysis. In response to this need, we have developed a digital microfluidic method and applied it to the extraction and quantification of estrogen in 1 microliter samples of breast tissue homogenate (as would be collected with fine-needle aspiration), as well as in whole blood and serum. This method may be broadly applicable to conditions requiring frequent analysis of hormones in clinical samples (for example, infertility and cancer).

Since the emergence of PID controllers, control system engineers are in pursuit of more and more sophisticated versions of these controllers to achieve better performance, particularly in situations where providing a control action to even a minimal degree of satisfaction is a problem. This work is an attempt to contribute in this field. Variations in the values of weight, the friction coefficient of the road, road inclination and other nonlinear dynamics may highly affect the performance of antilock braking systems (ABS). A self-tuning scheme seems necessary to overcome these effects. Addition of automatic tuning tool can track changes in system operation and compensate for drift due to aging and parameter uncertainties. The paper develops a self-tuning PID control scheme with application to ABS via combinations of fuzzy and genetic algorithms (GAs). The control objective is to minimize the stopping distance while keeping the slip ratio of the tires within desired range. Computer simulations are performed to verify the proposed control scheme. Results are reported and discussed.

This paper presents a simple-to-construct, low dead volume pump capable of generating a wide range of positive and negative pressures for microfluidic applications. The pump generates pressure or vacuum by changing the volume of air confined inside a syringe and is able to generate pressures between -95 kPa to +300 kPa with a resolution as high as 1 Pa. Different from syringe pumps and electrokinetic pumping, which are capable of controlling flow rates only, our pump can be used to generate constant flow rates or constant pressures which are required for certain applications such as the aspiration of biological cells for biophysical characterization. Compared to syringe pumps, the new pump has almost zero dead volume and does not exhibit pulsatile flows. Additionally, the system does not require electrical power and is cost effective (~$100). To demonstrate the capabilities of the pump, we used it to aspirate osteoblasts (MC3T3-E1 cells) and to determine Young’s modulus of the cells, to generate a concentration gradient, and to produce variable-sized droplets in microchannels using hydrodynamic focusing.

In the present study, the transient performance of the viscous micropump will be investigated numerically. The viscous micropump's operation depends mainly on viscous forces and can operate in any situation where viscous forces are dominant. All the micropump calculations are reported in nondimensional quantities, which allows for the prediction of the micropump performance, regardless of the dimensions or the fluid that is used. The effect of the microchannel height, rotor eccentricity, Reynolds number, and pump load on the transient performance of the viscous micropump has been studied in detail. The steady state performance was compared with the available experimental data and was found to be in a very good agreement. The rotor eccentricity was determined to be the parameter that affected the transient performance of the micropump the most significantly. This work provides a foundation for future research on the subject of fluid phenomena in viscous micropumps.