Dynamical Systems on Hilbert C*-Modules

We investigate the generalized derivations and show that every generalized derivation on a simple Hilbert $C^*$-module either is closable or has a dense range. We also describe dynamical systems on a full Hilbert $C^*$-module ${\mathcal M}$ over a $C^*$-algebra ${\mathcal A}$ as a one-parameter group of unitaries on ${\mathcal M}$ and prove that if $\alpha: \R\to U({\mathcal M})$ is a dynamical system, where $U({\mathcal M})$ denotes the set of all unitary operator on ${\mathcal M}$, then we can correspond a $C^*$-dynamical system $\alpha^{'}$ on ${\mathcal A}$ such that if $\delta$ and $d$ are the infinitesimal generators of $\alpha$ and $\alpha^{'}$ respectively, then $\delta$ is a $d$-derivation.Comment: 7 pages, minor changes, to appear in Bull. Iranian Math. So

Dietary glycemic index and glycemic load in relation to mortality from cardiovascular disease: a review of epidemiologic evidence

زمینه و هدف: در طول دهه‌های گذشته، همواره بیماری‌های قلبی عروقی به عنوان اولین عامل مرگ و میر در سراسر دنیا شناخته شده است. تغییرات نامناسب در الگوی رژیم غذایی، از جمله افزایش مصرف کربوهیدرات‌های تصفیه شده با نمایه گلیسمیک (GI: Glycemic index) و بار گلیسمیک (GL: Glycemic Load) بالا، از مهمترین عوامل خطرزای محیطی در افزایش بیماری‌های قلبی عروقی است. این مطالعه با هدف مروری بر مطالعات پیشین، جهت بررسی ارتباط بین GI و GL رژیم غذایی و مرگ و میر ناشی از انواع بیماری‌های قلبی عروقی انجام شده است. روش بررسی: در این مطالعه مروری با جستجو در PubMed با کلید واژه‌های Glycemic index ، Cardiovascular disease (CVD) و mortality صورت گرفت. تا کنون مطالعات محدودی در این زمینه انجام شده که روش‌ها و نتایج حاصل از این مطالعات در این مقاله مورد بررسی قرار گرفته است. تمام مطالعات انجام شده، از نوع بررسی‌های آینده‌نگر بوده که بر روی انسان انجام شده است. یافته‌ها: نتایج مطالعات حاکی از آن است که ارتباط بین GI و GL رژیم غذایی و مرگ و میر بیماری‌های قلبی عروقی، معنی دار نبوده و تنها در زنان میانسال و مسن ژاپنی، ارتباط مثبت و معنی داری بین GI و GL رژیم غذایی و مرگ و میر ناشی از سکته اسکیمیک (خطر نسبی: 45/2 و فاصله اطمینان 95: 01/1 تا 92/5) مشاهده شده است. نتیجه‌گیری: نتیجه‌گیری بر اساس شواهد و یافته‌های موجود کار دشواری است و تعیین چگونگی ارتباط بین نمایه‌گلیسمیک و بارگلیسمیک رژیم غذایی و مرگ و میر ناشی از انواع بیماریهای قلبی و عروقی، نیازمند مطالعه و تحقیقات بیشتر، در این زمینه است

A Multiband OFDMA Heterogeneous Network for Millimeter Wave 5G Wireless Applications

Citation: Niknam, S., Nasir, A. A., Mehrpouyan, H., & Natarajan, B. (2016). A Multiband OFDMA Heterogeneous Network for Millimeter Wave 5G Wireless Applications. Ieee Access, 4, 5640-5648. doi:10.1109/access.2016.2604364Emerging fifth generation (5G) wireless networks require massive bandwidth in higher frequency bands, extreme network densities, and flexibility of supporting multiple wireless technologies in order to provide higher data rates and seamless coverage. It is expected that the utilization of the large bandwidth in the millimeter-wave (mmWave) band and deployment of heterogeneous networks (HetNets) will help address the data rate requirements of 5G networks. However, high pathloss and shadowing in the mmWave frequency band, strong interference in the HetNets due to massive network densification, and coordination of various air interfaces are challenges that must be addressed. In this paper, we consider a relay based multiband orthogonal frequency division multiple access HetNet in which mmWave small cells are deployed within the service area of macro cells. In particular, we attempt to exploit the distinct propagation characteristics of mmWave bands (i.e., 60 GHz-the V-band and 70-80 GHz the E-band) and the long term evolution band to maximize overall data rate of the network via efficient resource allocation. The problem is solved using a modified dual decomposition approach and then a low complexity greedy solution based on the iterative activity selection algorithm is presented. Simulation results show that the proposed approach outperforms conventional schemes

Thermal Management for S-NUCA Many-Cores via Synchronous Thread Rotations

On-chip thermal management is quintessential to a thermally safe operation of a many-core processor. The presence of a physically distributed logically shared Last-Level Cache (LLC) significantly reduces the performance penalty of migrating threads within the cores of an S-NUCA many-core. This cost reduction allows novel thermal management of these many-cores via synchronous thread migration. Synchronous thread migration provides a viable alternative to Dynamic Voltage and Frequency Scaling (DVFS) and asynchronous thread migration used traditionally to manage thermals of S-NUCA many-cores. We present a theoretical method to compute the peak tem-perature in many-cores with synchronous thread migrations. We use the method to create a thermal management heuristic called HotPotato that maximizes the performance of S-NUCA many-cores under a peak temperature constraint. We implement HotPotato within the state-of-the-art HotSniper simulator. Detailed interval thermal simulations with HotSniper show an average 10.72% improvement in response time of S-NUCA many-cores when scheduling with HotPotato compared to a state-of-the-art thermal-aware S-NUCA scheduler

Unitarily invariant norm inequalities for operators

We present several operator and norm inequalities for Hilbert space operators. In particular, we prove that if $A_{1},A_{2},...,A_{n}\in {\mathbb B}({\mathscr H})$, then $$|||A_{1}A_{2}^{*}+A_{2}A_{3}^{*}+...+A_{n}A_{1}^{*}|||\leq|||\sum_{i=1}^{n}A_{i}A_{i}^{*}|||,$$ for all unitarily invariant norms. We also show that if $A_{1},A_{2},A_{3},A_{4}$ are projections in ${\mathbb B}({\mathscr H})$, then &&|||(\sum_{i=1}^{4}(-1)^{i+1}A_{i})\oplus0\oplus0\oplus0|||&\leq&|||(A_{1}+|A_{3}A_{1}|)\oplus (A_{2}+|A_{4}A_{2}|)\oplus(A_{3}+|A_{1}A_{3}|)\oplus(A_{4}+|A_{2}A_{4}|)||| for any unitarily invariant norm.Comment: 10 pages, Accepted pape

3D-TTP: Efficient Transient Temperature-Aware Power Budgeting for 3D-Stacked Processor-Memory Systems

The heat produced during computation severely limits the performance of multi-/many-core processors. High-performance 3D-stacked processor-memory systems stack cores and main memory on a single die. However, 3D-stacked systems suffer more severe thermal issues than their non-stacked planar 2D counterparts. Consequently, the aggressive thermal throttling required for their thermally-safe operation limits the potential performance gains. Power budgeting is an effective thermal management technique that prevents thermal throttling in multi-/many-core processors by assigning a thermally-safe power budget to cores within the processors. State-of-the-art power budgeting techniques for 2D processors do not account for the vertical thermal coupling between the layers of the 3D-stacked system and will fail to prevent thermal throttling in them. Furthermore, estimating thermals for a 3D-stacked processor with power budgeting requires a finer-grained RC thermal model than non-stacked processors. This requirement inhibits the porting of existing power budgeting solutions for 2D processors to 3D-stacked processor-memory systems. This work is the first to present the linear algebra-based algorithmic time-invariant transformations required to enable power budgeting in 3D-stacked systems. Based on the transformations, we propose the first transient-temperature-aware power budgeting technique, 3D-TTP, for 3D-stacked systems. Detailed interval thermal simulations with the advanced CoMeT simulator designed for 3D-stacked systems also confirm no thermal violations with our 3D-TTP technique. 3D-TTP exhibits an average 11.41% speedup over the state-of-the-art reactive-based thermal management technique

Analysis of acoustic emission data for bearings subject to unbalance

Acoustic Emission (AE) is an effective nondestructive method for investigating the behavior of materials under stress. In recent decades, AE applications in structural health monitoring have been extended to other areas such as rotating machineries and cutting tools. This research investigates the application of acoustic emission data for unbalance analysis and detection in rotary systems. The AE parameter of interest in this study is a discrete variable that covers the significance of count, duration and amplitude of AE signals. A statistical model based on Zero-Inflated Poisson (ZIP) regression is proposed to handle over-dispersion and excess zeros of the counting data. The ZIP model indicates that faulty bearings can generate more transient wave in the AE waveform. Control charts can easily detect the faulty bearing using the parameters of the ZIP model. Categorical data analysis based on generalized linear models (GLM) is also presented. The results demonstrate the significance of the couple unbalance