Energy Optimization in Commercial FPGAs with Voltage, Frequency and Logic Scaling

This paper investigates the energy reductions possible in commercially available FPGAs configured to support voltage, frequency and logic scalability combined with power gating. Voltage and frequency scaling is based on in-situ detectors that allow the device to detect valid working voltage and frequency pairs at run-time while logic scalability is achieved with partial dynamic reconfiguration. The considered devices are FPGA-processor hybrids with independent power domains fabricated in 28 nm process nodes. The test case is based on a number of operational scenarios in which the FPGA side is loaded with a motion estimation core that can be configured with a variable number of execution units. The results demonstrate that voltage scalability reduces power by up to 60 percent compared with nominal voltage operation at the same frequency. The energy analysis show that the most energy efficiency core configuration depends on the performance requirements. A low performance scenario shows that serial computation is more energy efficient than the parallel configuration while the opposite is true when the performance requirements increase. An algorithm is proposed to combine effectively adaptive voltage/logic scaling and power gating in the proposed system and application

miR-101 sensitizes K562 cell line to imatinib through Jak2 downregulation and inhibition of NF-κB target genes

Imatinib mesylate (IM) is a frontline treatment in the early chronic phase of chronic myeloid leukemia (CML). However, intrinsic and acquired resistance against this drug has been defined and this issue has become a problem and a challenge in CML treatment. According to new findings, the inhibition of Janus kinase 2 (Jak2) in Bcr�Abl+ cells can promote apoptosis in IM-resistant cells. microRNAs (miRNAs) regulate the gene expression by targeting the messenger RNA (mRNA) for degradation. Recently, a growing body of evidence has implicated that dysregulation of miRNAs is associated with cancer initiation and development. In this report, we proposed that miRNA-101 targets Jak2 mRNA and regulates its expression and induces K562 leukemia cell apoptosis. Here, we transduced the K562 cell line with a miR-101-overexpressing vector and evaluated the Jak2 mRNA level. Our results showed that miR-101 overexpression in Bcr�Abl+ cells reduced the Jak2 mRNA level. Moreover, imatinib treatment and miR-101 upregulation led to miR-23a overexpression, which has putative binding site(s) on 3�-untranslated regions (3�-UTRs) of STAT5, CCND1, and Bcl-2 genes. Our results also indicated that miR-101 overexpression inhibited cell proliferation indicated by the MTT assay and promoted apoptosis detected via flow cytometry. Importantly, mRNA expression of NF-kappa B-regulated anti-apoptotic (Bcl-2, Bcl-xl, MCL-1, XIAP, and survivin) and proliferative (c-Myc and CCND1) genes was decreased. These findings suggest that miR-101 acts as a tumor suppressor by downregulating Jak2 expression and sensitizing K562 cells to imatinib. Therefore, restoration of miR-101 may be a therapeutic approach for CML treatment. © 2016, International Society of Oncology and BioMarkers (ISOBM)

A Theoretical Survey on the Potential Performance of a Perovskite Solar Cell Based on an Ultrathin Organic-Inorganic Electron Transporting Layer

An ultrathin perovskite solar cell with 29.33 % theoretical power conversion efficiency (PCE) is designed for flexible applications. The perovskite layer is sandwiched between two multijunctions, i.e. poly(3- hexylthiophene) (P3HT), nickel oxide (NiO), and copper (I) thiocyanate (CuSCN) as the hole transporting element, from one side, and zinc oxide (ZnO), tin (IV) oxide (SnO2) and phenyl-C61 butyric acid methyl ester (PCBM) as the electron transporting compartment, from the other side. This study uses a professional software package to accurately simulate a series of highly efficient perovskite-based solar cell structures that use both organic and inorganic materials. Calculations are simultaneously run with SCAPS (version. 3.3.07). The materials system for the electron transporting multijunction, bandgap of the perovskite layer, defection density, temperature of operating conditions, and concentration of charge doping are manipulated as the tuning parameters. An excellent fill factor (84.76 %), a potentially low entire thickness (⁓ 1 µm), and compatible nature for both organic and inorganic materials make this layout auspicious for a feasible and versatile high efficiency, but low-cost electronic devices. The constituent materials are selected based on the thickness and photoconversion efficiency. In order to assess the further potentials of materials system, we replaced CuSCN with PTAA (Polytriarylamine) and observed an increase in the theoretical efficiency, and we investigated the effect of varying the doping concentration in the PTAA layer. To simulate this structure, both the electrical and physical properties of the materials are considered, and the results are compared with those of previous works. These results should be of significant interest to experimentalists in the field

Optimization and characterization of zeolite-titanate for ibuprofen elimination by sonication/hydrogen peroxide/ultraviolet activity

In this study, a photo-catalyst of titanium oxide was coated on zeolite by the sol–gel method. The generation of the zeolite-titanate photo-catalyst was optimized at conditions of calcination temperature (300, 350, 400 and 500 °C), calcination time (1, 2, 3, and 4 h), and titanate content (0, 2, 4, 6, and 8 mL). The catalyst was used for ‘Sonication/UV/H2O2″ activity and finally, eliminating ibuprofen. Physicochemical properties of the as-built photo-catalysts for all optimized conditions were determined using FESEM-EDX-mapping, BET, FTIR, and XRD. The highest percentage of ibuprofen removal (98.9%) was obtained at conditions of zeolite to titanium ratio of 1 g: 2 mL, time in the furnace of 1 h, and temperature of the furnace of 350 °C. The optimum photo-catalytic (namely, Cat-350-1-2) had a surface area value of 39 m2/g and a crystalline size of 4.9 nm. The surface area for all photo-catalysts increased after being used for ibuprofen removal, possibly due to ultrasonic waves. The presence of Ti-O, benzene ring, O-Al-O, O-Si-O, C–H, and O–H in the photo-catalysts structure were confirmed. Growing the calcination time resulted in an increase in the crystallinity of titanium dioxide in the photo-catalysts and, ultimately a reduction in the ibuprofen removal. The consumed energy by the developed system was calculated for the presence (0.094 kJ/g) and absence (17.5 kJ/g) of the ultrasonic wave. The degradation pathway and reaction kinetic are also explored and proposed. The results showed that the ultrasonic-UV-activated H2O2-based technique can be applied as an alternative method for ibuprofen removal from aqueous medi

Energy Flow Simulation of the Uneven Span Glass Greenhouse with Special Structure using Computational Fluid Dynamics (CFD)

IntroductionGreenhouse cultivation is the popular intensive kind of crop production with a yield per cultivated unit area more than 10 times higher compared to field crops. Greenhouse production requires the use of large amounts of energy, water, and pesticides and it usually generates huge quantities of wastes to be disposed of it. Investment, labor, and energy costs per unit area are much higher in the greenhouse industry than in any other agricultural sectors. Sustainable greenhouse systems, socially supportive, commercially competitive, and environmentally sound, depend on cultivation techniques, equipment management, and constructive materials that aim to reduce agrochemicals, energy and water consumption as well as waste generation. The management of the greenhouse environment is depending on temperature manipulation. Temperature manipulation is critical to influencing plant growth, quality, and morphology and so is a major strategy in the environmental modification of crops. Heterogeneous indoor microclimate of a greenhouse has long become a matter of concern in many studies. It is believed to be unfavorable for crop growth, which damages crop activity, particularly transpiration and photosynthesis, one of the major causes of non-uniform production and quality. Since early and conventional methods are not sufficient to evaluate microclimate variables inside a greenhouse, Computational Fluid Dynamics (CFD) approach was applied for better and more accurate results. CFD is an effective numerical analysis technique to predict the distribution of the climatic variables inside cultivation facilities. Numerous studies have focused on the internal temperature, humidity, solar radiation, and airflow inside multiple cultivation facilities. For example, the CFD method was used to simulate natural ventilation for agricultural buildings and improve crop production systems. The CFD simulation and evaluation models could be applied for evaluation of the inside situation and temperature in greenhouses. Thermal and water vapor transfer is influenced by the openings of greenhouses in the CFD simulation. The CFD model was developed to predict the distribution of temperature, water vapor, and CO2 occurring in a Venlo-type semi-closed glass greenhouse equipped with air conditioners. Based on the above literature, this research aims to evaluate the energy flow and modeling of an un-even semi-buried greenhouse using external and internal variables and numerical solutions by the CFD method.Materials and MethodsIn this study, Computational Fluid Dynamic (CFD) solution was applied to evaluate the inside environment of a semi-double glass greenhouse with an east-west location. This greenhouse has a special structure that is used in very hot or very cold areas due to its depth of more than one meter below the ground. The greenhouse has an area of 38m2 and an air volume of 78.8m3. The temperature and humidity data were collected from inside and outside the greenhouse by temperature sensors (SHT 11 model made by CMOS USA). Irradiation data were collected inside the greenhouse, on level ground, by the TES132 radiometer.Results and DiscussionIn this study, the CFD method was used for a model solution with ANSYS Fluent version 2020R2 software. To evaluate the predictive capability of the model and its optimization, the comparison between actual (ya) and predicted values (yp) was used. Three criteria of RMSE, MAPE, and R2 were also used to evaluate the accuracy of the final model. The results showed that the dynamic model can accurately estimate the temperature of the air inside the greenhouse at a height of 1 m (R2 = 0.987, MAPE = 2.17%) and 2 m (R2 = 0.987, MAPE = 2.28%) from the floor. The results of energy flow showed that this greenhouse transfers 6779.4.4 kJ of accumulated thermal energy to the ground during the experiment.ConclusionIn the present study, the computational fluid dynamics method was used to simulate the internal conditions of an un-even semi-buried greenhouse with external and internal variables including temperature and solar radiation. The results showed that this greenhouse structure is able to transfer part of the increase in temperature caused by sunlight to the soil depth (104.214 kJm-2 heat through the floor, 178.443 kJm-2 through the north wall and 113.757 kJm-2 through the south wall). By increasing the thermal conductivity of the inner surface of the greenhouse, the heat flux to the depth of the soil can be increased

BIODESULFURIZATION OF SIMULATED LIGHT FUEL OIL BY A NATIVE ISOLATED BACTERIA BACILLUS CEREUS HN

In the present paper, the biodesulfurization of simulated light fuel oil (i.e., dibenzothiophene (DBT) in dodecane) and untreated kerosene with a high total sulfur content has been studied by a native isolated bacterium named Bacillus cereus HN. The influences of various parameters such as the reaction temperature (T), biocatalyst cell density, oil phase fraction (OFP), and initial DBT concentration on the fractional conversion of the model sulfur compound were investigated. The experimental data obtained were used to determine the reaction rate constant of the model sulfur compound and the corresponding activation energy. Furthermore, the biodesulfurization of un-treated kerosene with a total sulfur content of 2333 ppmw produced by an Iranian refinery company (Isfahan refinery) was investigated to examine the capability of this new microorganism. It was realized that about 33% of the total sulfur content of untreated kerosene could be removed after 72 hrs. The results of the response surface methodology (RSM) showed that a quadratic correlation could be proposed for the influences of biocatalyst cell density, OFP, and initial DBT concentration on the desulfurization of DBT.</span

Application of Low Concentration Surfactant Enhanced Water-Alternating-Gas Flooding

Large amounts of oil left in the petroleum reservoir after primary and secondary enhanced oil recovery methods have brought about the implementation of several tertiary means of oil recovery. Increment of oil recovery can support the world’s oil supply. Water alternating gas injection has been a very popular method of gas injection to improving volumetric sweep efficiency. Although water alternating as injection has been shown to improve oil recovery, this process suffers inherent challenges such as water blocking, mobility control in high viscosity oil and gravity segregation. To combat these problems associated with water alternating gas flooding, the use of surfactant has been employed in water alternating gas injection. Due to the high operational cost arising from chemical cost in surfactant alternating gas injection, a new technique which involves the injection of low concentration surfactant before water alternating as flooding has been proposed. This work investigates experimental and numerical oil recovery potential of surfactant enhanced water alternating gas flooding. The distinctive feature of this technique is that instead of injecting surfactant slugs alternatively with gas, which will result to using a greater amount of surfactant, a low concentration surfactant is injected into the reservoir before water alternating gas flooding. The aim is to evaluate the performance of this technique as a low cost and effective means of chemically enhanced oil recovery by combining both mechanisms of surfactant reduction of water-oil interfacial tension and creation of foam with gas. This study begins with surfactant evaluation to characterise surfactants compatibility with reservoir brine and oil. Then followed by series core flooding experiments which include waterflooding, gas flooding, water alternating gas flooding and surfactant-enhanced water alternating gas flooding. Core flood data was history matched for water alternating as flooding and surfactant-enhanced water alternating as flooding via commercial simulator by inputting relative permeability curves, rock, fluid properties and interfacial tension. The results showed that experimentally, surfactant enhanced water alternating as flooding had the highest oil recovery when compared to conventional enhanced oil recovery methods. History matching of core flood experiment predicted similar increment in oil recovery during surfactant enhanced WAG. The effectiveness of this technique is based on the injection pattern after the initial surfactant injection and oil recovery potential is similar to that of surfactant alternating gas flooding