Coverage and Spectral Efficiency of Network Assisted Full Duplex in a Millimeter Wave System

To cope with the growing trend of asymmetric data traffic, we introduce a novel network assisted full duplex (NAFD) for a millimeter wave system. NAFD can dynamically allocate the number of remote radio heads in the uplink mode or in the downlink mode, which can facilitate simultaneous uplink and downlink communications. In this manuscript, we use stochastic geometry to analyze the distribution of the signal-to-interference-plus-noise ratio and the data rate in a NAFD system. The numerical results verify the analysis and show that the NAFD outperforms the dynamic time division duplex system and the traditional flexible duplex system in terms of spectral efficiency.

Duplex Anti-Corrosion Protection of Steel Using a Combination of Hot-Dip Galvanising and Water-Soluble Paints

The goal of this paper is an evaluation of research aimed at corrosion and mechanical resistance of the so-called duplex system applied to a steel sheet. This system consists of a metal coating applied by hot-dip galvanising, to which an acrylic, water-soluble paint is commonly applied (commonly available on the Czech market) using standard technology in an air stream. For the purposes of the corrosion resistance comparison, one set of test specimens is provided only with a hot-dip galvanised coating. The mechanical resistance of applied anti-corrosion protection was determined by means of a pull-off adhesion test (according to the ČSN EN ISO 4624 standard), as well as an indentation test (according to the ČSN EN ISO 1520 standard). The corrosion resistance tests were then conducted in a salt spray environment (according to the ČSN EN ISO 9227 standard) for the samples not damaged by mechanical tests. Based on the obtained results, in general, waterborne paints with high dry matter content, low specific gravity and high zinc phosphate content, which are applied in several thinner layers, can be recommended.

Duplex Sign Language Communicator

In this paper we are introducing a sign language converter which works as a duplex system as it can convert text to sign language as well as it can do a real time video to text conversion. It is basically a system that can be used by all people who know sign language as well as who are not familiar with it. The main aim of this system is to involve the specially abled people as much as possible to interact with others. Our system uses the basic NLP i.e. the Natural language Processing and algorithms like CNN classifier to make the implementation of this translator. Along with that this system focuses on the Indian Sign Language so that it can be used by our country people. The finger gestures are captured by the camera and using various machine learning algorithms the system will automatically translate the signs to the readable text, similarly in sign to text conversion, based on the data sets and various Machine learning algorithms the text will be converted to sign language.

Beware the ureteric stone hidden in a duplex system

Level of evidence: 5

MSE minimized joint transmission in coordinated multipoint systems with sparse feedback and constrained backhaul requirements

In a joint transmission coordinated multipoint (JT-CoMP) system, a shared spectrum is utilized by all neighbor cells. In the downlink, a group of base stations (BSs) coordinately transmit the users’ data to avoid serious interference at the users in the boundary of the cells, thus substantially improving area fairness. However, this comes at the cost of high feedback and backhaul load; In a frequency division duplex system, all users at the cell boundaries have to collect and send feedback of the downlink channel state information (CSI). In centralized JT-CoMP, although with capabilities for perfect coordination, a central coordination node have to send the computed precoding weights and corresponding data to all cells which can overwhelm the backhaul resources. In this paper, we design a JT-CoMP scheme, by which the sum of the mean square error (MSE) at the boundary users is minimized, while feedback and backhaul loads are constrained and the load is balanced between BSs. Our design is based on the singular value decomposition of CSI matrix and optimization of a binary link selection matrix to provide sparse feedback—constrained backhaul link. For comparison, we adopt the previously presented schemes for feedback and backhaul reduction in the physical layer. Extensive numerical evaluations show that the proposed scheme can reduce the MSE with at least $$25\%$$ 25 % , compared to the adopted and existing schemes.

Obstructed Right Upper Moiety in a Bilateral Partial Duplex Renal System in an Adult

Duplex renal system, a common congenital anomaly of the kidney and urinary tract, is preferably identified through screening. For obstructed symptomatic duplications, prompt relief of obstruction to forestall renal parenchymal loss is recommended. We present a case of neglected obstruction of the right upper moiety in an adult female with discordant bilateral renal duplex system. A 49-year-old female with a 10-year history of recurrent right flank pain and fever presented for clinical evaluation and treatment. She had no such symptoms in early childhood. A diagnosis was made of obstructed right upper renal moiety in bilateral discordant renal duplication with complete moiety parenchymal destruction. She had right renal exploration with complete excision of the hydronephrotic sac and the grossly dilated moiety ureter down to the obstruction at the fusion of both upper and lower moiety ureters. Her postoperative period was uneventful. She is symptomfree and her urinary tract is structurally intact. Hitherto asymptomatic renal duplication can become symptomatic in early adulthood from intrinsic moiety ureter obstruction, suggesting a need for lifetime monitoring of persons with duplex renal systems. Late presentation with neglected symptoms, and consequent renal moiety destruction as seen here, is a result of the absence of such monitoring. Keywords: Duplex renal system, Obstruction

From Doppler to duplex: A personal early history of the vascular laboratory

In the mid-1970s, a group of clinicians and bioengineers at the University of Washington, under the direction of Dr D Eugene Strandness, Jr, built a prototype duplex scanner that combined B-mode imaging and pulsed Doppler flow detection in a single instrument. At that time, I was a general surgery resident with an interest in vascular disease, and arrangements were made for me to spend a year in the Strandness laboratory. The prototype duplex system was just being completed when I arrived in 1978, and I immediately became involved in a series of validation studies in which patients with carotid disease were scanned and spectral waveform parameters were correlated with independently read contrast arteriograms. This work resulted in the University of Washington duplex criteria for carotid artery disease, which have been widely adopted and modified. Subsequent advances in ultrasound technology expanded the applications of duplex scanning to the peripheral arteries and veins, as well as the abdominal vessels. In 1984, I joined Dr Strandness on the faculty in the Department of Surgery at the University of Washington where I have remained throughout my career. Over the years, I have had the opportunity to participate in many important developments, described in this article, that have helped to make the vascular laboratory the essential clinical resource that it is today.