346 research outputs found

    Electronically Tunable Resistorless Mixed Mode Biquad Filters

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    This paper presents a new realization of elec¬tronically tunable mixed mode (including transadmittance- and voltage-modes) biquad filter with single input, three outputs or three inputs, single output using voltage differ-encing transconductance amplifier (VDTA), a recently introduced active element. It can simultaneously realize standard filtering signals: low-pass, band-pass and high-pass or by selecting input terminals, it can realize all five different filtering signals: low-pass, band-pass, high-pass, band-stop and all-pass. The proposed filter circuit offers the following attractive feature: no requirement of invert-ing type input signal which is require no addition circuit, critical component matching conditions are not required in the design, the circuit parameters ω0 and Q can be set orthogonally or independently through adjusting the bias currents of the VDTAs, the proposed circuit employs two active and minimum numbers of passive components. Fur-thermore, this filter was investigated from the point of view of limited frequency range, stability conditions, effects of parasitic elements and effects of non-ideal and sensitivity. Thus, taking these effects and conditions into considera¬tion, working conditions and boundaries of this filter are determined. We also performed Monte Carlo, THD and noise analyses. Simulation results are given to confirm theoretical analyses

    The electron diffusion coefficient tensor by using the real geometry of the Earth’s magnetic field in ionospheric plasma

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    In this study, the electron diffusion coefficients are calculated as depending on latitude, local time and seasonal in the ionospheric plasma by using the real geometry of Earth’s magnetic field for north hemisphere. It is observed that if the earth’s magnetic field is taken into account, the medium is anisotropic in ionospheric plasma. Due to this, the electron diffusion coefficients have tensorial form in the ionospheric plasma. As general, there is a harmony between change of the electron diffusion coefficient and the change of the electron density with local time in the ionospheric plasmaBu çalışmada, dünyanın gerçek manyetik alan geometrisi kullanılarak kuzey yarım küre için iyonosferik plazmada elektron difüzyon katsayıları yüksekliğe, yerel zamana ve mevsime bağlı olarak hesaplandı. Eğer dünyanın manyetik alanı hesaba katılırsa iyonosferik plazmada ortam anizotropik olur. Bundan dolayı iyonosferik plazmada elektron difüzyon katsayısı tensörel bir forma sahiptir. Genel olarak, elektron difüzyon katsayısının yerel zamanla değişimi ve elektron yoğunluğun yerel zamanla değişimi arasında bir uyum vardı

    The seasonal behavior of the refractive index of the ionosphere over the equatorial region

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    In this study, the seasonal behavior of the refractive index of the ionosphere over equator region is investigated both for collisional and collisionless cases by using the real geometry of Earth’s magnetic field for north hemisphere with respect to latitudes. It is observed that there is a harmony between the behavior of the electron density distribution and extra ordinary waves both for collisional and collisionless cases at hmF2 peak in the ionosphere.Bu çalışmada, ekvator bölgesinde iyonosferin kırılma indisinin mevsimsel davranışı, dünyanın gerçek manyetik alan geometrisi kullanılarak hem çarpışmalı hemde çarpışmasız durumlarda, kuzey yarım küre için enleme göre çalışılmıştır. İyonsferin hmF2 (F2- bölgesinin tepe yüksekliği) de çarpışmalı ve çarpışmasız durum için elektron yoğunlu dağılımı ile exra-ordinary dalgnın davranışı arasında bir uyum olduğu görülmüştü

    A Template-Based Design Methodology for Graph-Parallel Hardware Accelerators

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    Graph applications have been gaining importance in the last decade due to emerging big data analytics problems such as Web graphs, social networks, and biological networks. For these applications, traditional CPU and GPU architectures suffer in terms of performance and power consumption due to irregular communications, random memory accesses, and load balancing problems. It has been shown that specialized hardware accelerators can achieve much better power and energy efficiency compared to the general purpose CPUs and GPUs. In this paper, we present a template-based methodology specifically targeted for hardware accelerator design of big-data graph applications. Important architectural features that are key for energy efficient execution are implemented in a common template. The proposed template-based methodology is used to design hardware accelerators for different graph applications with little effort. Compared to an application-specific high-level synthesis methodology, we show that the proposed methodology can generate hardware accelerators with up to 18× better energy efficiency and requires less design effort

    Architectural requirements for energy efficient execution of graph analytics applications

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    Intelligent data analysis has become more important in the last decade especially because of the significant increase in the size and availability of data. In this paper, we focus on the common execution models and characteristics of iterative graph analytics applications. We show that the features that improve work efficiency can lead to significant overheads on existing systems. We identify the opportunities for custom hardware implementation, and outline the desired architectural features for energy efficient computation of graph analytics applications. © 2015 IEEE

    Hardware accelerator design for data centers

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    As the size of available data is increasing, it is becoming inefficient to scale the computational power of traditional systems. To overcome this problem, customized application-specific accelerators are becoming integral parts of modern system on chip (SOC) architectures. In this paper, we summarize existing hardware accelerators for data centers and discuss the techniques to implement and embed them along with the existing SOCs. © 2015 IEEE

    Functional biology of the Steel syndrome founder allele and evidence for clan genomics derivation of COL27A1 pathogenic alleles worldwide

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    © 2020, The Author(s). Previously we reported the identification of a homozygous COL27A1 (c.2089G\u3eC; p.Gly697Arg) missense variant and proposed it as a founder allele in Puerto Rico segregating with Steel syndrome (STLS, MIM #615155); a rare osteochondrodysplasia characterized by short stature, congenital bilateral hip dysplasia, carpal coalitions, and scoliosis. We now report segregation of this variant in five probands from the initial clinical report defining the syndrome and an additional family of Puerto Rican descent with multiple affected adult individuals. We modeled the orthologous variant in murine Col27a1 and found it recapitulates some of the major Steel syndrome associated skeletal features including reduced body length, scoliosis, and a more rounded skull shape. Characterization of the in vivo murine model shows abnormal collagen deposition in the extracellular matrix and disorganization of the proliferative zone of the growth plate. We report additional COL27A1 pathogenic variant alleles identified in unrelated consanguineous Turkish kindreds suggesting Clan Genomics and identity-by-descent homozygosity contributing to disease in this population. The hypothesis that carrier states for this autosomal recessive osteochondrodysplasia may contribute to common complex traits is further explored in a large clinical population cohort. Our findings auNorthwell Healthnt our understanding of COL27A1 biology and its role in skeletal development; and expand the functional allelic architecture in this gene underlying both rare and common disease phenotypes

    Preferences and priorities for relapsed multiple myeloma treatments among patients and caregivers in the United States

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    Introduction/Background: This study aimed to describe patient and caregiver preferences for treatments of relapsed or refractory multiple myeloma (MM). Materials and Methods: A survey including discrete-choice experiment (DCE) and best-worst scaling (BWS) exercises was conducted among US patients with relapsed or refractory MM and their caregivers. The DCE included six attributes with varying levels including progression-free survival (PFS), toxicity, and mode and frequency of administration. In addition, the impact of treatment cost was assessed using a fixed-choice question. The BWS exercise included 18 items (modes and frequency of administration, additional treatment convenience, and toxicity items). The survey was administered online to patients recruited from the Multiple Myeloma Research Foundation CoMMpass study (NCT01454297). Results: The final samples consisted of 94 patients and 32 caregivers. Avoiding severe nerve damage was most important to patients, followed by longer PFS. Caregivers considered PFS to be the most important attribute. We estimate that a third or more of patients were cost-sensitive, meaning their treatment preference was altered based on cost implications. Caregivers were not cost-sensitive. The three most bothersome treatment features in the BWS exercise were risk of kidney failure, lowering white blood cell counts, and weakening the immune system. Conclusion: Patients with relapsed or refractory MM and their caregivers consider many factors including efficacy, toxicity, mode/frequency of administration, and cost in their decisions regarding treatment options. The study provides a basis for future Research on patient and caregiver treatment preferences, which could be incorporated into shared decision-making with physicians

    Energy Efficient Architecture for Graph Analytics Accelerators

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    Specialized hardware accelerators can significantly improve the performance and power efficiency of compute systems. In this paper, we focus on hardware accelerators for graph analytics applications and propose a configurable architecture template that is specifically optimized for iterative vertex-centric graph applications with irregular access patterns and asymmetric convergence. The proposed architecture addresses the limitations of the existing multi-core CPU and GPU architectures for these types of applications. The SystemC-based template we provide can be customized easily for different vertex-centric applications by inserting application-level data structures and functions. After that, a cycle-accurate simulator and RTL can be generated to model the target hardware accelerators. In our experiments, we study several graph-parallel applications, and show that the hardware accelerators generated by our template can outperform a 24 core high end server CPU system by up to 3x in terms of performance. We also estimate the area requirement and power consumption of these hardware accelerators through physical-aware logic synthesis, and show up to 65x better power consumption with significantly smaller area. © 2016 IEEE

    Graph Analytics Accelerators for Cognitive Systems

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    Hardware accelerators are known to be performance and power efficient. This article focuses on accelerator design for graph analytics applications, which are commonly used kernels for cognitive systems. The authors propose a templatized architecture that is specifically optimized for vertex-centric graph applications with irregular memory access patterns, asynchronous execution, and asymmetric convergence. The proposed architecture addresses the limitations of existing CPU and GPU systems while providing a customizable template. The authors' experiments show that the generated accelerators can outperform a high-end CPU system with up to 3 times better performance and 65 times better power efficiency. © 1981-2012 IEEE
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