147 research outputs found
A Modular Platform for Adaptive Heterogeneous Many-Core Architectures
Multi-/many-core heterogeneous architectures are shaping current and upcoming generations of compute-centric platforms which are widely used starting from mobile and wearable devices to high-performance cloud computing servers. Heterogeneous many-core architectures sought to achieve an order of magnitude higher energy efficiency as well as computing performance scaling by replacing homogeneous and power-hungry general-purpose processors with multiple heterogeneous compute units supporting multiple core types and domain-specific accelerators. Drifting from homogeneous architectures to complex heterogeneous systems is heavily adopted by chip designers and the silicon industry for more than a decade. Recent silicon chips are based on a heterogeneous SoC which combines a scalable number of heterogeneous processing units from different types (e.g. CPU, GPU, custom
accelerator).
This shifting in computing paradigm is associated with several system-level design challenges related to the integration and communication between a highly scalable number of heterogeneous compute units as well as SoC peripherals and storage units. Moreover, the increasing design complexities make the production of heterogeneous SoC chips a monopoly for only big market players due to the increasing development and design costs. Accordingly, recent initiatives towards agile hardware development open-source tools and microarchitecture aim to democratize silicon chip production for academic and commercial usage.
Agile hardware development aims to reduce development costs by providing an ecosystem for open-source hardware microarchitectures and hardware design processes. Therefore, heterogeneous many-core development and customization will be relatively less complex and less time-consuming than conventional design process methods.
In order to provide a modular and agile many-core development approach, this dissertation proposes a development platform for heterogeneous and self-adaptive many-core architectures consisting of a scalable number of heterogeneous tiles that maintain design regularity features while supporting heterogeneity. The proposed platform hides the integration complexities
by supporting modular tile architectures for general-purpose processing cores
supporting multi-instruction set architectures (multi-ISAs) and custom hardware accelerators. By leveraging field-programmable-gate-arrays (FPGAs), the self-adaptive feature of the many-core platform can be achieved by using dynamic and partial reconfiguration (DPR) techniques.
This dissertation realizes the proposed modular and adaptive heterogeneous many-core platform through three main contributions. The first contribution proposes and realizes a many-core architecture for heterogeneous ISAs. It provides a modular and reusable tilebased architecture for several heterogeneous ISAs based on open-source RISC-V ISA. The modular tile-based architecture features a configurable number of processing cores with different RISC-V ISAs and different memory hierarchies.
To increase the level of heterogeneity to support the integration of custom hardware accelerators, a novel hybrid memory/accelerator tile architecture is developed and realized as the second contribution. The hybrid tile is a modular and reusable tile that can be configured at run-time to operate as a scratchpad shared memory between compute tiles or as an accelerator tile hosting a local hardware accelerator logic. The hybrid tile is designed and implemented to be seamlessly integrated into the proposed tile-based platform.
The third contribution deals with the self-adaptation features by providing a reconfiguration management approach to internally control the DPR process through processing cores (RISC-V based). The internal reconfiguration process relies on a novel DPR controller targeting FPGA design flow for RISC-V-based SoC to change the types and functionalities of compute tiles at run-time
A cache framework for nomadic clients of web services
This research explores the problems associated with caching of SOAP Web Service request/response pairs, and presents a domain independent framework enabling transparent caching of Web Service requests for mobile clients. The framework intercepts method calls intended for the web service and proceeds by buffering and caching of the outgoing method call and the inbound responses. This enables a mobile application to seamlessly use Web Services by masking fluctuations in network conditions.
This framework addresses two main issues, firstly how to enrich the WS standards to enable caching and secondly how to maintain consistency for state dependent Web Service request/response pairs
Study Of Gan Low Dimensional Structures On Silicon Substrates Grown By Thermal Vapor Deposition For Photodiode And Solar Cell Applications
Gallium nitride (GaN) is a greatly promising wide band gap semiconductor with applications in high power electronic and optoelectronic devices. Heterostructure solar cell involving GaN low Dimensional (low D) structures on single crystalline silicon (Si) substrates are the preferable choice as they have excellent internal quantum efficiencies, large open-circuit voltages, and low processing cost. This thesis examines the growth of GaN low D structures on Si substrates using inexpensive thermal vapor deposition (TVD) techniques for solar cell and photodiode (PD) devices. The growth was achieved using two methods. The first method involved the growth of GaN low D structures on n-Si (111) in NH3-free environments by TVD via thermal evaporation of GaN powder under different carrier gases, substrate temperatures and deposition times. The result showed that the morphology and shape of GaN low D structures are highly dependent on each parameter. The X-ray diffraction and Raman spectra of the low D structures indicated that the GaN structure had a hexagonal wurtzite structure. The TVD is optimized by using 1h deposition time and 1000ᵒC temperature to obtain uniform dense low D structures with good crystalline quality and hence enhanced performance of PD and solar cell devices
Impact of corporate income taxation on capital structure in developing Southeast Asian nations: empirical evidence from Tiger Cub Corporations
The increasing investment in the Tiger Cub Nations of Indonesia, Malaysia, Philippines, Thailand, and Vietnam has driven the developing nations towards greater industrialization and to becoming export leaders in the Southeast Asian region. The integration and accelerated growth of their financial markets, in addition to investment incentives to attract foreign direct investment shape a critical environment for corporate and individual investors. While their economies sustain a fiscal policy through the implementation of corporate and personal taxation, this paper aims to highlight the impact of corporate income taxation on the capital structure of firms. Associated with the share of debt in corporate capital, the investigation dissects into the impact of corporate taxation on leverage, while considering capital structure determinants as control factors as proposed by conventional literature. This paper enlists local stock-exchange listed firms and their debt structure during the period 2008-2019, following the global financial crisis and corporate tax reforms in Malaysia
Shoahliteratur im deutsch-jüdisch-arabischen Kontext: Der Gerechte unter den Völkern Mohammed Helmy als literarisches Motiv. Mit Unterrichtsvorschlägen für arabischsprechende Deutschlernende.
Diese Dissertation befasst sich mit deutschsprachigen Texten über den aus Ägypten stammenden Berliner Arzt Mohammed Helmy, der 2013 postum von der israelischen Gedenkstätte Yad Vashem mit dem Ehrentitel Gerechter unter den Völkern ausgezeichnet wurde, weil er die Jüdin Anna Boros-Gutman vor der Deportation versteckte. Die Texte werden in den Kontext der Shoahliteratur gebracht und analysiert. Nach Lieferung von grundlegenden Informationen und Klärung von zentralen Begriffen wird die Entwicklung der Shoahliteratur beschrieben. Dabei wird der Fokus auf den aktuellen Wandel der Shoahliteratur gelegt, insbesondre weil in den letzten Jahren viele Bücher erschienen sind, die sich mit wahren Begebenheiten anhand von Archivmaterialien beschäftigen. Die Textanalyse beginnt mit der Untersuchung ausgewählter Archivunterlagen auf ihre autobiographischen Züge hin. Danach werden zwei Biographien: Der Muslim und die Jüdin von Ronen Steinke und Mod Helmy von Igal Avidan (beide 2017) analysiert. Überdies wird ein Familienroman von Jürgen Seidel Die Rettung einer ganzen Welt (2018), der auf der wahren Geschichte basiert, ausführlich untersucht. Diese Textanalysen dienten als eine zielführende Grundlage für den zweiten Teil der Arbeit bzw. für die Didaktisierung der Erlebnisse M. Helmys im DaF/DaZ-Unterricht. Es werden drei kulturreflexive Unterrichtsvorschläge erstellt, die spezifisch für arabischsprechende Deutschlernende konzipiert werden und zwischen sprachbezogenen und kulturbezogenen Lernzielen verbinden
Ultrasound Prediction of the Mode of Delivery in the Second Stage of Labor Using the Fetal Head-Symphysis Distance
OBJECTIVE:
To evaluate whether the fetal head-symphysis distance measured by three-dimensional transperineal ultrasound during the active second stage predicts operative delivery.
DESIGN:
Prospective observational study.
SETTING:
University hospital, Bologna, Italy.
POPULATION:
Seventy-one nulliparous women at term in active second stage of labor.
METHODS:
We acquired a series of sonographic volumes at the beginning of the active second stage (T1) and every 20 min thereafter (T2, T3, T4, T5, T6) until delivery. All volumes were retrospectively analyzed and head-symphysis distance was measured for each acquisition. We compared head-symphysis distance between women with spontaneous vaginal delivery and those with operative delivery. Receiver operator characteristic curves were constructed to estimate the accuracy of head-symphysis distance in the prediction of operative delivery. Logistic regression was used to identify independent variables associated with operative delivery.
MAIN OUTCOME MEASURES:
Operative delivery (vacuum or cesarean).
RESULTS:
Of the women included, 81.7% had a spontaneous vaginal delivery and 18.3% underwent operative delivery. Women with spontaneous vaginal delivery had shorter head-symphysis distance than women in the operative delivery group at T1 (p < 0.001), T2 (p < 0.001) and T3 (p = 0.025), whereas no significant differences were recorded thereafter. Receiver operator characteristic curves revealed accuracy values of 81.0%, 87.9% and 77.6% in the prediction of operative delivery at T1, T2 and T3, respectively. At multivariate logistic regression head-symphysis distance and epidural analgesia were the only independent predictors of operative delivery among ultrasonographic, maternal and intrapartum variables.
CONCLUSIONS:
Ultrasonographic measurement of head-symphysis distance in the second stage of labor can be used to predict operative delivery
∈φ-contraction and some fixed point results via modified ω-distance mappings in the frame of complete quasi metric spaces and applications
In this Article, we introduce the notion of an ∈φ-contraction which based on modified ω-distance mappings and employ this new definition to prove some fixed point result. Moreover, we introduced an interesting example and an application to highlight the importance of our work
A Computational Approach to a Mathematical Model of Climate Change Using Heat Sources and Diffusion
The present work aims to extend the climate change energy balance models using a heat source. An ordinary differential equations (ODEs) model is extended to a partial differential equations (PDEs) model using the effects of diffusion over the spatial variable. In addition, numerical schemes are presented using the Taylor series expansions. For the climate change model in the form of ODEs, a comparison of the presented scheme is made with the existing Trapezoidal method. It is found that the presented scheme converges faster than the existing scheme. Also, the proposed scheme provides fewer errors than the existing scheme. The PDEs model is also solved with the presented scheme, and the results are displayed in the form of different graphs. The impact of the climate feedback parameter, the heat uptake parameter of the deep ocean, and the heat source parameter on global mean surface temperature and deep ocean temperature is also portrayed. In addition, these recently developed techniques exhibit a high level of predictability. Doi: 10.28991/CEJ-2022-08-07-04 Full Text: PD
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