Combined Time and Information Redundancy for SEU-Tolerance in Energy-Efficient Real-Time Systems

Recently the trade-off between energy consumption and fault-tolerance in real-time systems has been highlighted. These works have focused on dynamic voltage scaling (DVS) to reduce dynamic energy dissipation and on time redundancy to achieve transient-fault tolerance. While the time redundancy technique exploits the available slack time to increase the fault-tolerance by performing recovery executions, DVS exploits slack time to save energy. Therefore we believe there is a resource conflict between the time-redundancy technique and DVS. The first aim of this paper is to propose the usage of information redundancy to solve this problem. We demonstrate through analytical and experimental studies that it is possible to achieve both higher transient fault-tolerance (tolerance to single event upsets (SEU)) and less energy using a combination of information and time redundancy when compared with using time redundancy alone. The second aim of this paper is to analyze the interplay of transient-fault tolerance (SEU-tolerance) and adaptive body biasing (ABB) used to reduce static leakage energy, which has not been addressed in previous studies. We show that the same technique (i.e. the combination of time and information redundancy) is applicable to ABB-enabled systems and provides more advantages than time redundancy alone

Comments on “Flow, thermal, and entropy generation characteristics inside a porous channel with viscous dissipation” by S. Mahmud and R.A. Fraser [Int. J. Thermal Sciences 44 (2005) 21–32]

Hoomen, Merrikh and Ejlali presents comment on the paper on 'Flow, thermal, and entropy generation characteristics inside a porous channel with viscous dissipation' by S. Mahmud and R.A. Fraser. The paper presents closed form solutions to the velocity and temperature distributions that would be very useful for checking numerical computations. The authors have applied the fluid thermal conductivity kf in all of the equations, that should be replaced by the effective thermal conductivity. They have presented the temperature distribution and the Nusselt number as a function of the Darcy number only, inspite of the fact that Re, Pr, and Ec will affect the temperature profile. The authors have applied a clear-fluid compatible term in the entropy production term that has not been already considered in the thermal energy equation. The reliability of the numerical results is questionable though the authors have applied a previously tested numerical scheme

Distribution and pollution level of nickel and vanadium in sediments from south part of the Caspian Sea, Iran

765-771Distribution and pollution level of nickel and vanadium in sediment from south part of the Caspian Sea, north of Iran, were studied. Sediment samples obtained by Van Veen Grab from four stations, including, Turkaman, Amirabad, Fereydunkenar and Noushahr along the south part of the Caspian Sea, during fall of 2015 and april, summer and winter of 2016. The concentrations of metal were ranged from 21.63 µg/g to 55.45 µg/g for nickel and from 58.23 µg/g to 146.27 µg/g for vanadium in sediments samples collected from all stations. There was significant difference in metals concentration between different stations along the Caspian Sea (P < 0.05), and the highest mean concentration of metals was absorbed in Fereydunkenar estuary, followed by Amirabad, Turkaman and Noushahr, respectively. The results showed that there were significant differences between metals pollution during four seasons (P < 0.05), and the highest concentration of metals were absorbed in dry season (summer) and the lowest concentration in wet season (winter). There was a positive correlation between nickel and vanadium concentration in sediment samples, and the Pearson correlation was (r = 0.67) between nickel and vanadium in sediment samples. The positive correlation between heavy metals can be related to same source of both metals in the environment. Based on our results, anthropogenic activities such as oil industry and agriculture activities are the main sources of pollution in the coasts along south part of Caspian Sea

Sustainability in Historical Houses of Tabriz and its Insignificant Role in Contemporary Houses

ABSTRACT During recent decades, large cities such as Tabriz where urban development phenomenon is increasingly growing encounter many problems. In transition from historical to contemporary houses of Tabriz, historical houses clearly lost some of their values and factors as well as local knowledge, naturalism and saving energy which played a role in contemporary houses. Moreover, changes made during &apos;Transform and Restore Iranian Historical Cities Program&apos; including Tabriz, resulted in changes in form and structure of residential buildings which does not consider environmental issues; while a development program is considered a sustainable development so that in long-term it qualitatively improves human health and ecological systems. Sustainable architecture theory is derived from this idea; basics and regulations used in this architecture clearly explain most new concepts in sustainable architecture area. Hence the study attempts to identify and describe sustainability, to identify sustainability concepts on architecture, and to analyze these concepts on residential architecture of Tabriz. The study tries to achieve objective basics for sustainable design of Tabrizian buildings

Stractural and Morphological Characteristics of Whey Protein Concentrate-Modified Starch Complex: Effect of pH and Bioplymers Ratio

In this study, interaction between WPC and OSAS as a function of pH (3, 4, 5 and 6) and biopolymers ratio (1:2, 1:1 and 2:1) at total concentration of 1% w/w was investigated by measuring the structural (turbidity, particles size, Zeta potential, viscometery, FTIR) and morphological (SEM) properties. Maximum zeta potential was observed at 2:1 biopolymers ratio and pH=3. With increasing pH and decreasing ratio of WPC:OSAS, zeta potential value decreased. At ratio 1:2 and pH 6 minimum zeta potential was gained. Minimum particles size was observed at ratio 1:2 and pH=6 (0.819 µm) in which with decreasing pH to 4 and increasing ratio up to 2:1, it was maximized (2.260). Turbidity results was in accordance with particles size measurements and maximum and minimum results was observed at the same points. At ratio 1:2 and pH=4, maximum viscosity was observed (1.301 mPa.s). Reducing the ratio and increasing pH led to minimum viscosity at pH=6 and ratio 2:1 (1.147 mPa.s). In all measured characters, there was significant difference between control (WPC) and complex samples. FTIR study revealed that by complexation between WPC and OSAS, amid II peak was weakened and carboxylated and OSA group's peak were removed. SEM images showed that with formation of electrostatic complex, spherical structures of WPC and OSAS was changed to porous network and sheet structures

Fuel consumption in mining industry using partial least squares structural equation modeling approach

Purpose: Consumption of fossil fuels due to their non-renewability has always been one of the fundamental problems among energy-related issues. Major dependence of mining equipment and activities on energy, fuel and adequate fuel allocation has become of great importance in fuel consumption of mines. Therefore, this study aims to propose a model for optimal fuel allocation for mining industry. Design/methodology/approach: In this study, partial least squares structural equation modeling (PLS-SEM), as one of the well-known statistical methods, is used to model and analyze fuel consumption pattern in mine industry. Findings: To show the applicability of the proposed model, the study investigates the model for a real mine in Iran. In this regard, real data of important factors affecting mine fuel consumption are collected. Results of statistical models construct a general formula to calculate the fuel consumption based on three main variables. Originality/value: Policymaking is one of the important tasks in energy-related organizations. One of the main sectors that uses noticeable amount of fossil fuels is mining industry. Despite the government subsidy for mining in Iran, there is a significant price difference between the price of allocated fuel for mine and the price of the same fuel in the open market. Therefore, this study implements PLS-SEM approach to formulate the fuel consumption pattern under all possible fuel consumption indicators to enable policymakers to make reliable decision for future purposes

Spatial Distribution Variation and Probabilistic Risk Assessment of Exposure to Fluoride in Ground Water Supplies: A Case Study in an Endemic Fluorosis Region of Northwest Iran

Prevalence of fluorosis is a worldwide public health issue, especially in the West Azerbaijan province of Iran. The aim of this study was to investigate fluoride concentration in drinking water resources within Maku city, in both the warm and cold seasons, to perform a health risk assessment. Fluoride were measured using UV-visible spectrophotometry. The spatial distribution was calculated by the software ArcGIS and Hazard Quotients (HQs) were calculated according to the US EPA method. The fluoride concentrations ranged between 0.29 to 6.68 and 0.1 to 11.4 mg/L in the cold and warm seasons, respectively. Based on this report, 30.64 and 48.15% of the samples revealed a fluoride level higher than the permissible level in the cold and warm seasons, respectively. Moreover, results showed that the HQ value in the warm season for different age groups was higher than the HQ value in the cold season. In both seasons, the non-carcinogenic risks of fluoride for the four exposed populations varied according to the order: children &gt; teenagers &gt; adults &gt; infants. The HQ values for three age groups (children, teenager and adults) for both seasons were higher than 1 with a high risk of fluorosis. The results of this study, support the requests that government authorities better manage water supplies to improve health quality