Test data compression technique for embedded cores using virtual scan chains

This paper presents a design-for-test (DFT) technique to implement a "virtual scan chain" in a core that looks (to the system integrator) like it is shorter than the real scan chain inside the core. A core with a "virtual scan chain" is fully compatible with a core with a regular scan chain in terms of both the external test interface and tester program. The I/O pins of a core with a virtual scan chain are identical to the I/O pins of a core with a regular scan chain. For the system integrator, testing a core with a virtual scan chain is identical to testing a core with a regular scan chain (no special modes, control signals, or timing sequences are needed). The only difference is that the virtual scan chain is much shorter so the size of the scan vectors and output response is smaller resulting in less test data as well as less test time (fewer scan shift cycles). The process of mapping the virtual scan vectors to real scan vectors is handled inside the core and is completely transparent to the system integrator.     

Detection of charge storage on molecular thin films of tris(8-hydroxyquinoline) aluminum (Alq3) by Kelvin force microscopy: a candidate system for high storage capacity memory cells

Retention and diffusion of charge in tris(8-hydroxyquinoline) aluminum (Alq(3)) molecular thin films are investigated by injecting electrons and holes via a biased conductive atomic force microscopy tip into the Alq(3) films. After the charge injection, Kelvin force microscopy measurements reveal minimal changes with time in the spatial extent of the trapped charge domains within Alq(3) films, even for high hole and electron densities of >10(12) cm(-2). We show that this finding is consistent with the very low mobility of charge carriers in Alq(3) thin films (<10(-7) cm(2)/(Vs)) and that it can benefit from the use of Alq(3) films as nanosegmented floating gates in flash memory cells. Memory capacitors using Alq(3) molecules as the floating gate are fabricated and measured, showing durability over more than 10(4) program/erase cycles and the hysteresis window of up to 7.8 V, corresponding to stored charge densities as high as 5.4 × 10(13) cm(-2). These results demonstrate the potential for use of molecular films in high storage capacity nonvolatile memory cells.     

Mucous prolapse of the urethra

Urethral prolapse represent a rare cause of urological consultation. Frequent in older women, it also happens in under 10-year-old little girls with a racial predominance. For most cases, medical treatment and follow-up are sufficient, but failure of these or possible complications may necessitate a surgical correction. Circumferential excision and muco-mucous suture are effective treatments with very few complications. About four case-reports, we are reviewing here the literature and discussing etiopathogenic mechanisms and therapeutic options for this disease.     

Graphene quantum dots rescue protein dysregulation of pancreatic β-cells exposed to human islet amyloid polypeptide

Nano Research - The amyloid aggregation of peptides and proteins is a hallmark of neurological disorders and type 2 diabetes. Human islet amyloid polypeptide (IAPP), co-secreted with insulin by...     

Analytical method for optimal design of RF dual‐band rat‐race couplers for arbitrary frequency ratios

This article presents an analytical method to design a hybrid structure dual‐band rat‐race coupler at microwave frequencies. The proposed structure uses six identical cells of which each is engineered to work as a quarter wavelength transmission line with proper characteristic impedance at two distinct frequencies having arbitrary frequency ratio. The performances of the π‐ and T‐cells are studied to assess their ability to provide the required electrical parameters for dual‐band operation. It is demonstrated that the single‐section π‐topology can only lead to a suboptimal design for a dual‐band rat‐race cell at two nonharmonic frequencies. In contrast, the proposed double‐section π‐cell structure allows achieving an optimal dual‐band cell design. A dual‐band rat‐race coupler designed at 2.14 and 3.6 GHz has been simulated and fabricated in hybrid microstrip technology. Measurement results agree well with analytically based simulation results, which demonstrate the effectiveness of the proposed structure for dual‐band operation. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22: 690–700, 2012.     

Stability and Stabilization of Fractional‐Order Systems with Different Derivative Orders: An LMI Approach

Stability and stabilization analysis of fractional‐order linear time‐invariant (FO‐LTI) systems with different derivative orders is studied in this paper. First, by using an appropriate linear matrix function, a single‐order equivalent system for the given different‐order system is introduced by which a new stability condition is obtained that is easier to check in practice than the conditions known up to now. Then the stabilization problem of fractional‐order linear systems with different fractional orders via a dynamic output feedback controller with a predetermined order is investigated, utilizing the proposed stability criterion. The proposed stability and stabilization theorems are applicable to FO‐LTI systems with different fractional orders in one or both of 0 <  α  < 1 and 1 ≤  α  < 2 intervals. Finally, some numerical examples are presented to confirm the obtained analytical results.     

Large‐signal modeling methodology for GaN HEMTs for RF switching‐mode power amplifiers design

A large‐signal model for GaN HEMT transistor suitable for designing radio frequency power amplifiers (PAs) is presented along with its parameters extraction procedure. This model is relatively easy to construct and implement in CAD software since it requires only DC and S‐parameter measurements. The modeling procedure was applied to a 4‐W packaged GaN‐on‐Si HEMT, and the developed model is validated by comparing its small‐ and large‐signal simulation to measured data. The model has been employed for designing a switching‐mode inverse class‐F PA. Very good agreement between the amplifier simulation and measurement shows the validity of the model. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.     

Parametric study of droplet size in an axisymmetric flow-focusing capillary device

A conventional technique for microfluidic droplet generation is Co-axial Flow Focusing(CFF) in which a contraction zone is placed downstream of the dispersed phase nozzle. In this contraction zone, the dispersed-phase(dphase) fluid is pinched off by continuous-phase(c-phase) fluid to generate micro-droplets. Studying the influence of multiple parameters such as the fluids velocities and viscosities, the interfacial tension, and nozzle and orifice diameters on the droplet size is of great importance for the design and application of CFF devices. Thus,development of more complete numerical models is required. In this paper, we show our model is compatible with experimental data and then numerically investigate the effects of aforementioned parameters on the droplet generation in a CFF microfluidic device. Simulation results showed that the c–phase flow rate, viscosity and the interfacial tension had great impacts on the droplet size. The effect of the nozzle diameter on the generated droplet size was small compared to that of the orifice in a CFF device. Using the simulation results, a correlation was also developed and suggested which predicts the droplet size with less than 15% error in a wide range of the introduced dimensionless parameters.