Effect of Hydrostatic Pressure on the Revers Gate-Current of AlGaN/GaN HEMTs

In this paper, we present an analytical-Numerical model for reverse gate leakage current in AlGaN/GaN high electron mobility transistors, which investigate the influence of the hydrostatic pressure (HP) on gate-current.  It has been found that the bound charge at the heterointerface has the most impact on the threshold voltage. The increases in hydrostatic pressure cause an increase in threshold voltage. With increasing HP, the Schottky barrier height decreases, AlGaN electric field and reverse gate leakage current are increased. The increase in HP acts as a positive virtual gate. The dependence on the HP of Poole- Frenkel emission (FP) and Fowler-Nordheim (FN) direct tunneling is more than trap-assisted-tunneling (TAT). Increasing the pressure of 2GPa, the intersection point of PF and TAT varies by 1 volt, and the PF range increases compared to TAT.&nbsp

Effect of Hydrostatic Pressure and Temperature on Quantum Confinement of AlGaN/GaN HEMTs

In this paper, an analytical model for quantum confinement electron density in two-dimensional quantum well, has been investigated. In order to obtain the exact AlGaN/GaN HEMTs parameters such as electron density, the wave function, band gap, polarization charge, effective mass and dielectric constant, the hydrostatic pressure and temperature effects are taken into account. It has been found that the electron density decreases with increasing temperature and increases with increasing hydrostatic pressure. With increasing hydrostatic pressure, the effective mass decreases and the quantum confinement electrons are increased in the quantum well. Also with increasing hydrostatic pressure, the height of wave functions increase and decreases electron wave functions to penetrate the quantum barrier but increasing the temperature behaves the opposite of increasing the pressure.   However, with increasing temperature, the effective mass is increased and the quantum confinement electrons are reduced. The calculated results for electron density are in good agreement with existing experimental data

Optimal lower bounds for universal relation, and for samplers and finding duplicates in streams

In the communication problem $\mathbf{UR}$ (universal relation) [KRW95], Alice and Bob respectively receive $x, y \in\{0,1\}^n$ with the promise that $x\neq y$. The last player to receive a message must output an index $i$ such that $x_i\neq y_i$. We prove that the randomized one-way communication complexity of this problem in the public coin model is exactly $\Theta(\min\{n,\log(1/\delta)\log^2(\frac n{\log(1/\delta)})\})$ for failure probability $\delta$. Our lower bound holds even if promised $\mathop{support}(y)\subset \mathop{support}(x)$. As a corollary, we obtain optimal lower bounds for $\ell_p$-sampling in strict turnstile streams for $0\le p < 2$, as well as for the problem of finding duplicates in a stream. Our lower bounds do not need to use large weights, and hold even if promised $x\in\{0,1\}^n$ at all points in the stream. We give two different proofs of our main result. The first proof demonstrates that any algorithm $\mathcal A$ solving sampling problems in turnstile streams in low memory can be used to encode subsets of $[n]$ of certain sizes into a number of bits below the information theoretic minimum. Our encoder makes adaptive queries to $\mathcal A$ throughout its execution, but done carefully so as to not violate correctness. This is accomplished by injecting random noise into the encoder's interactions with $\mathcal A$, which is loosely motivated by techniques in differential privacy. Our second proof is via a novel randomized reduction from Augmented Indexing [MNSW98] which needs to interact with $\mathcal A$ adaptively. To handle the adaptivity we identify certain likely interaction patterns and union bound over them to guarantee correct interaction on all of them. To guarantee correctness, it is important that the interaction hides some of its randomness from $\mathcal A$ in the reduction.Comment: merge of arXiv:1703.08139 and of work of Kapralov, Woodruff, and Yahyazade

Symptomatic Müllerian Duct Cyst in a Male Adult: A Rare Case Report

Background: Müllerian duct cyst is an uncommon congenital anomaly. It is usually small and asymptomatic. A rare case of this entity with symptoms of ejaculatory duct obstruction such as hematospermia and secondary infertility is presented here.Case Report: A 39-year-old male presented with complaints of pain in the lower abdomen, dysuria, frequency, and hematospermia for the last 2 years. He also suffered from secondary infertility with a 9-year-old son. Imaging studies showed a large cystic midline lesion right behind the bladder and also bilateral dilated ejaculatory ducts. The patient underwent a transurethral drainage. The prostatic urethra was resected using a 26 Fr resection loop proximal to the verumontanum and a capacious cystic structure opened, and finally two dilated ejaculatory duct openings were seen. On follow-up, a significant improvement of symptoms and semen quality was achieved after surgery.Conclusions: A high index of suspicion in using advanced imaging modalities is necessary for the diagnosis of this anomaly. Surgical excision of a Müllerian duct cyst may be performed depending on the size and location of the cyst and the presence of clinical symptoms. Transurethral de-roofing of the cyst is effective and safe for the treatment of small Müllerian duct cyst accompanied with ejaculatory duct obstruction

Numerical Optimization for Source-Drain Channel Resistance of AlGaN/GaN HEMTS

A numerical model for the source-drain channel resistance based high electron mobility transistors has been developed that is capable to predict accurately the effects of polarization Coulomb Field Scattering (PCF), multi sub-band on source-drain channel resistance. Salient features of the model are incorporated of fully and partially occupied sub-bands in the interface quantum well, combined with a self-consistent solution of the Schrödinger and Poisson equations. In addition, to develop the model, accurate two-dimensional electron gas mobility and modified wave function in barrier AlGaN have been used. According to the numerical calculations, the effect of multi sub-band and PCF scattering on the increase of source-drain channel resistance is 35% and 65%, respectively, with the effect of PCF being almost twice as high as multi sub-band. The calculated model results are in very good agreement with existing experimental data for high electron mobility transistors device

Numerical Performance of AlGaN/GaN High Electron Mobility Transistors under Hydrostatic Pressure and Temperature

In this paper, drain-source current, in AlGaN/GaN high electron mobility transistors have been investigated. In order to obtain parameters of exact AlGaN/GaN high electron mobility transistors such as electron density, the wave function, band gap, polarization charge, effective mass and dielectric constant, the hydrostatic pressure and temperature effects are taken into account. It has been found that the drain-source current decreases with increasing temperature and increases with increasing hydrostatic pressure. The increase in temperature is equivalent to a negative virtual gate and an increase in the hydrostatic pressure equivalent to the positive virtual gate voltage. Moreover, the temperature and hydrostatic pressure effective mass dependence in high electron mobility transistor structures are investigated, and it is observed that the increase of hydrostatic pressure decreases the effective mass and the wave function penetrated to quantum barrier AlGaN. The calculated results are in good agreement with existing experimental data

Protozoans; (Coccidia and Myxosporea;) infections in some fishes of Aras and Mahabad Dams (Northwest of Iran)

During a protozoological study on the fishes of West-Azarbayejan province (Northwest of Iran) in 1998, three different protozoans were revealed. Myxobolus musayevi from Capoeta capoeta, Myxobolus dispar from Aspius aspius taeniatus and Goussia carpelli from Cyprinus carpio. Altogether 13 different fish specimen were examined. The fishes including: Aspius aspius taeniatus (2), Rutilus ruti/us (3), Capoeta cpoeta (2) and Cyprinus carpio (6). They were caugth from Aras and Mahabad Dams and transported alive to the laboratory where they were wieghted and measured. Then, they were examined for protozoan infections when their spinal cord was cut. Myxobolus musayevi had already reported from Capoeta capoeta from Taj an in Mazandaran province. This is the first record of Myxobolus dispar from Aspius aspius taeniatus from Iranian freshwaters. Goussia carpelli also had already recorded (unpublished) from the Cyprinus carpio from Sepeedroud River in Guilan province. In this study, three of C. carpio which were caught from Aras Dam had been infected by the oocyst of the Goussia carpelli in the mocus of the intestine

Dynamics of Droplets

Capturing non-Newtonian power-law drops by horizontal thin fibers with circular crosssection in a quiescent media can be studied in this chapter. The case is simulated using volume of fluid (VOF) method providing a notable reduction of a computational cost. Open source OpenFOAM software is applied to conduct the simulations. This model is an extension of the one developed earlier by Lorenceau, Clanet, and Quéré [1]. To validate the model, water drops affecting a fiber of radius 350μm were simulated and threshold drop radiuses were obtained regarding to the impact velocity. These results agreed well with the experimental data presented by Lorenceau et al. [1]. In the next step, non-Newtonian power-law drops landing on thin fiber of radius 350μm were simulated. The final goal of this study was to obtain the threshold velocity and radius of a drop that is completely captured by the fiber. Threshold radiuses for both shear-thinning and shear-thickening drops were obtained and compared with corresponding Newtonian drops. Results show that the threshold radius of drop increases in a fixed velocity as n, power-law index, increases. Furthermore, shear-thinning nature of the drop leads to instabilities in high Reynolds numbers (Re) as it influences the fiber

Unusual presentation of synovial sarcoma as meniscal cyst: A Case Report

Periarticular cyst and cystic soft tissue lesion around the knee are common. Synovial sarcoma is a rare and malignant soft tissue tumor accounting for approximately 5 of soft tissue sarcoma. A case is presented where a lesion adjacent to the joint line of the knee was diagnosed clinically and on imaging as a meniscal cyst. MRI signal was homogenous and no concomitant meniscal tears were seen. The tissue diagnosis was monophasic synovial sarcoma. © 2015 BY THE ARCHIVES OF BONE AND JOINT SURGERY