Hybrid NRZ/Multi-Tone Signaling for High-Speed Low-Power Wireline Transceivers

Over the past few decades, incessant growth of Internet networking traffic and High-Performance Computing (HPC) has led to a tremendous demand for data bandwidth. Digital communication technologies combined with advanced integrated circuit scaling trends have enabled the semiconductor and microelectronic industry to dramatically scale the bandwidth of high-loss interfaces such as Ethernet, backplane, and Digital Subscriber Line (DSL). The key to achieving higher bandwidth is to employ equalization technique to compensate the channel impairments such as Inter-Symbol Interference (ISI), crosstalk, and environmental noise. Therefore, todayâs advanced input/outputs (I/Os) has been equipped with sophisticated equalization techniques to push beyond the uncompensated bandwidth of the system. To this end, process scaling has continually increased the data processing capability and improved the I/O performance over the last 15 years. However, since the channel bandwidth has not scaled with the same pace, the required signal processing and equalization circuitry becomes more and more complicated. Thereby, the energy efficiency improvements are largely offset by the energy needed to compensate channel impairments. In this design paradigm, re-thinking about the design strategies in order to not only satisfy the bandwidth performance, but also to improve power-performance becomes an important necessity. It is well known in communication theory that coding and signaling schemes have the potential to provide superior performance over band-limited channels. However, the choice of the optimum data communication algorithm should be considered by accounting for the circuit level power-performance trade-offs. In this thesis we have investigated the application of new algorithm and signaling schemes in wireline communications, especially for communication between microprocessors, memories, and peripherals. A new hybrid NRZ/Multi-Tone (NRZ/MT) signaling method has been developed during the course of this research. The system-level and circuit-level analysis, design, and implementation of the proposed signaling method has been performed in the frame of this work, and the silicon measurement results have proved the efficiency and the robustness of the proposed signaling methodology for wireline interfaces. In the first part of this work, a 7.5 Gb/s hybrid NRZ/MT transceiver (TRX) for multi-drop bus (MDB) memory interfaces is designed and fabricated in 40 nm CMOS technology. Reducing the complexity of the equalization circuitry on the receiver (RX) side, the proposed architecture achieves 1 pJ/bit link efficiency for a MDB channel bearing 45 dB loss at 2.5 GHz. The measurement results of the first prototype confirm that NRZ/MT serial data TRX can offer an energy-efficient solution for MDB memory interfaces. Motivated by the satisfying results of the first prototype, in the second phase of this research we have exploited the properties of multi-tone signaling, especially orthogonality among different sub-bands, to reduce the effect of crosstalk in high-dense wireline interconnects. A four-channel transceiver has been implemented in a standard CMOS 40 nm technology in order to demonstrate the performance of NRZ/MT signaling in presence of high channel loss and strong crosstalk noise. The proposed system achieves 1 pJ/bit power efficiency, while communicating over a MDB memory channel at 36 Gb/s aggregate data rate

Design of a Nanometric AlTi Additive for MgB2-Based Reactive Hydride Composites with Superior Kinetic Properties

Solid-state hydride compounds are a promising option for efficient and safe hydrogen-storage systems. Lithium reactive hydride composite system 2LiBH4 + MgH2/2LiH + MgB2 (Li-RHC) has been widely investigated owing to its high theoretical hydrogen-storage capacity and low calculated reaction enthalpy (11.5 wt % H2 and 45.9 kJ/mol H2). In this paper, a thorough investigation into the effect of the formation of nano-TiAl alloys on the hydrogen-storage properties of Li-RHC is presented. The additive 3TiCl3·AlCl3 is used as the nanoparticle precursor. For the investigated temperatures and hydrogen pressures, the addition of ∼5 wt % 3TiCl3·AlCl3 leads to hydrogenation/dehydrogenation times of only 30 min and a reversible hydrogen-storage capacity of 9.5 wt %. The material containing 3TiCl3·AlCl3 possesses superior hydrogen-storage properties in terms of rates and a stable hydrogen capacity during several hydrogenation/dehydrogenation cycles. These enhancements are attributed to an in situ nanostructure and a hexagonal AlTi3 phase observed by high-resolution transmission electron microscopy. This phase acts in a 2-fold manner, first promoting the nucleation of MgB2 upon dehydrogenation and second suppressing the formation of Li2B12H12 upon hydrogenation/dehydrogenation cycling.Fil: Le, Thi-Thu. Helmholtz Zentrum Geesthacht; AlemaniaFil: Pistidda, Claudio. Helmholtz Zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Helmholtz Zentrum Geesthacht; Alemania. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Castro Riglos, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Helmholtz Zentrum Geesthacht; Alemania. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Karimi, Fahim. Helmholtz Zentrum Geesthacht; AlemaniaFil: Skibsted, Jørgen. University Aarhus; DinamarcaFil: Gharibdoust, Seyedhosein Payandeh. University Aarhus; DinamarcaFil: Richter, Bo. University Aarhus; DinamarcaFil: Emmler, Thomas. Helmholtz Zentrum Geesthacht; AlemaniaFil: Milanese, Chiara. Università di Pavia; ItaliaFil: Santoru, Antonio. Helmholtz Zentrum Geesthacht; AlemaniaFil: Hoell, Armin. Helmholtz Zentrum Berlin für Materialien und Energie; AlemaniaFil: Krumrey, Michael. Physikalisch Technische Bundesanstalt; AlemaniaFil: Gericke, Eike. Universität zu Berlin; AlemaniaFil: Akiba, Etsuo. Kyushu University; JapónFil: Jensen, Torben R.. University Aarhus; DinamarcaFil: Klassen, Thomas. Helmholtz Zentrum Geesthacht; Alemania. Helmut Schmidt University; AlemaniaFil: Dornheim, Martin. Helmholtz Zentrum Geesthacht; Alemani

Effects of intravenous Semelil (ANGIPARS�) on diabetic foot ulcers healing: A multicenter clinical trial

Some diabetic foot ulcers, which are notoriously difficult to cure, are one of the most common health problems in diabetic patients .There are several surgical and medical options which already have been introduced for treatment of diabetic foot ulcers, so some patient will require amputation. The purpose of this study was to evaluate the efficacy of intravenous Semelil (ANGIPARS�), a naive herbal extract to accelerate healing of diabetic foot ulcers. A multi-centric randomized controlled trial was conducted to evaluate intravenous Semelil for healing of diabetic foot ulcers. Sixteen diabetic patients were treated with intravenous Semelil, and nine other patients were treated with placebo as control group. Both groups were otherwise treated by wound debridement and irrigation with normal saline solution, systemic antibiotic therapy and daily wound dressing. Before and after intervention, the foot ulcer surface area was measured, by digital photography, mapping and planimetry. After 4 weeks, the mean foot ulcer surface area decreased from 479.93±379.75 mm2 to 198.93±143.75 mm2 in the intervention group (p = 0.000) and from 766.22±960.50 mm2 to 689.11±846.74 mm2 in the control group (p = 0.076). Average wound closure in the treatment group was significantly greater than placebo group (64 vs. 25, p= 0.015). This herbal extract by intravenous rout in combination with conventional therapy is more effective than conventional therapy by itself probably without side effect. However, further studies are required in the future to confirm these results in larger population

Intravenous Semelil (ANGIPARS�) as a novel therapy for pressure ulcers: A randomized clinical trial

The prevalence of pressure ulcers of the foot is a major health care problem in frail elderly patients. A pressure sore dramatically increases the cost of medical and nursing care, and effective treatment has always been an essential nursing concern. Management options for pressure ulcers include local wound care; surgical repair and, more recently, topical application of growth factors. The main goal of this study was to examine the effects of intravenous treatment of Semelil (ANGIPARS�), a new herbal extract in patients with severe, noninfected pressure ulcers of the foot. As a randomized clinical trial, 18 patients with pressure ulcers were recruited from Vali-e-Asr hospital, Medical Sciences/University of Tehran, Iran. Nine patients received intravenous Semelil (ANGIPARS�) besides to conventional therapy and nine received only conventional treatment. At the baseline, the treatment and control groups did not differ across demographic variables, clinical characteristics, and functional measures. The mean surface areas of the ulcers were reduced 43.2 ± 57.4 cm2 (80.3) and 2.8± 6.2 cm2 (6.3) in the treatment and control groups, respectively (p=0.000). The average reduction in pressure ulcer area at four weeks was statistically and clinically greater in the treatment group than in the control group So, intravenous Semelil (ANGIPARS�) can be recommended as an effective treatment for patients with severe pressure ulcers

Ölçekli silindirle-sıkıştırılmış-beton bır barajın sismik deneyi.

Within the last half-century, seismic response analysis of concrete gravity dams has been extensively studied. Studies reveal that two types of failure modes prevail in the form of dam body cracking or base slide. The literature lacks the conditions that clearly differentiate the two failure types. In this context a state of the art single degree of freedom pseudo-dynamic testing was developed to assess the gravity dam response on smooth foundation interface. Three different hazard levels of earthquake namely, Operational base earthquake (OBE), Maximum design earthquake (MDE) and Maximum characteristic earthquake (MCE) were employed during the course of the study. Subsequently a pushover test was performed to identify the reserve capacity of the scaled dam and its failure mode. The test results demonstrated the tendency of the scaled dam specimen to slide during MCE ground motion and eventually fail due to the rigid body sliding during the pushover test. A comparison was made between tip displacement and base slip acquired from the test and those values obtained from sliding analysis developed by Chopra and Zhang (1991b). Results were found to be in agreement and confirmed the approach by Chopra and Zhang (1991b). Finally thevi results were compared with the results from a companion specimen tested by Aldemir et al. (2015), which had a rough dam-foundation interface. It was found that base roughness is detrimental in defining the final failure mode of dams. M.S. - Master of Scienc

Seismic behaviour of roller compacted concrete dams under different base treatments

The effect of base roughness on the seismic behaviour of roller compacted concrete gravity dams were investigated by pseudo-dynamically testing two 1/75 scaled specimens with smooth and rough base treatments. Both specimens were tested under the effect of three different hazard level earthquakes and also a pushover experiment was conducted to obtain the capacity curve of each specimen. The smooth base specimen exhibited significant sliding under the effect of the maximum credible earthquake motion. In contrast, the rough base specimen had no base sliding response even during the pushover experiment, whereas large body cracks reaching almost the downstream toe of the specimen was the main reason for the loss of lateral strength. The numerical simulation of these two experiments were also conducted by using the sliding response analysis and the finite element method. The base sliding response of the smooth-base specimen was simulated successfully by considering a variable friction coefficient. The finite element results for the rough-base specimen was also promising as far as the base shear and tip displacement estimations were considered. However, the crack propagation estimates were inconclusive due to the severe diffusion of the cracks

A Method for Noise Reduction in Active- RC Circuits

A method for noise reduction in active-RC circuits is introduced. It is shown that the output noise in an active-RC circuit can be considerably reduced, without disturbing the circuit transfer function by inserting appropriate passive or active components in the circuit. The inserted components introduce new signal paths in the circuit for noise reduction while the original circuit transfer function is kept unchanged. The procedure to define the proper paths in the circuit and their transfer functions is given. The effectiveness of the presented method is demonstrated using a second-order active-RC filter fabricated in a 0.18-μm CMOS technology

Hybrid NRZ/Multi-Tone Serial Data Transceiver for Multi-Drop Memory Interfaces

A 7.5 Gb/s mixed NRZ/multi-tone transceiver for multi-drop bus (MDB) memory interfaces is designed and fabricated in 40 nm CMOS technology. Reducing the complexity of the equalization circuitry on the receiver (RX) side, the proposed architecture achieves 1 pJ/bit link efficiency for a MDB channel with 45 dB loss at 2.5 GHz. The transmitted spectrum is composed of baseband (BB) and I /Q sub-bands with the ability to match the modulation frequency of the entire transceiver (TRX) with respect to the channel response over a +/- 25% range. A switched-capacitor-based mixer/filter is developed to efficiently down convert and equalize the I /Q sub-bands in the RX. The core size area is 85 x 60 um2 and 150 x 60 um2 for the TX and RX, respectively

A 4×9 Gb/s 1 pJ/b Hybrid NRZ/Multi-Tone I/O with Crosstalk and ISI Reduction for Dense Interconnects

A low-power 4-channel hybrid NRZ/multi-tone transceiver for multi-drop bus (MDB) memory interfaces is designed and fabricated in 40 nm CMOS technology. The proposed system achieves 1 pJ/bit power efficiency, while communicating over an MDB channel with 45 dB loss at 3 GHz. The multi-tone (MT) nature of the proposed transceiver helps to control the intersymbol interference (ISI) and reduce the far-end crosstalk (FEXT), which results in a very energy-efficient implementation. The core size area is 80 x 60 um2 and 130 x60 um2 for the TX and RX blocks (including the clock unit), respectively

Analysis, Optimization, and Modeling of Analog Multi-Tone Serial Data Transceivers

This paper presents a versatile and fast time-domain architectural modeling framework for high-speed serial data transceivers (TRX) that can employ various analog modulation schemes. We highlight a modeling of TRXs employing an analog multi-tone signaling, which is not straightforward to model and hard to optimize with conventional serial link modeling tools. A method to limit the computing system’s memory usage when simulating a data transmission of a long bit-stream, e.g., greater than 10 Mbits, is also described. The reliability of the modeling framework is proven by some comparisons with a highly-trusted commercial tool for a conventional TRX architecture