115 research outputs found

    Universal feedback control of two-qubit entanglement

    Get PDF
    We consider two-qubit undergoing local dissipation and subject to local driving. We then determine the optimal Markovian feedback action to preserve initial entanglement as well as to create stationary entanglement with the help of an XY interaction Hamiltonian. Such feedback actions are worked out in a way not depending on the initial two-qubit state, whence called universal.Comment: 10 pages, 6 figure

    Evaluation and selection of thin-layer models for drying kinetics of apricot (cv. NASIRY)

    Get PDF
    E. Mirzaee, S. Rafiee, A. Keyhani(Agricultural Machinery Engineering Department, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran) Abstract: This paper presents the thin layer drying behavior of apricot (cv. NASIRY) at the air temperatures of 40ºC, 50ºC, 60ºC, 70ºC and air velocity of 1m/s and 2 m/s.  In order to select a suitable form of the drying curve, 12 different thin layer drying models were fitted to experimental data.  Fick’s second law was used as a major equation to calculate the moisture diffusivity with some simplification.  The high values of coefficient of determination and the low values of reduced chi-square and root mean square error indicated that the Logarithmic model and the Midilli et al. model could satisfactorily describe the drying curve of apricot for drying air velocity of 1m/s and 2 m/s, respectively.  According to the research results the calculated value of effective moisture diffusivity varied from 1.78×10-10–5.11×10-10 m2/s and the value of activation energy varied from a minimum of 24.01 kJ/mol to a maximum of 25.00 kJ/mol.Keywords: apricot, thin layer drying, effective moisture diffusivity, activation energy Citation: E. Mirzaee, S. Rafiee, A. Keyhani.  Evaluation and selection of thin-layer models for drying kinetics of apricot (cv. NASIRY).  Agric Eng Int: CIGR Journal, 2010, 12(2): 111-116.  &nbsp

    Pre-Training Multi-Modal Dense Retrievers for Outside-Knowledge Visual Question Answering

    Full text link
    This paper studies a category of visual question answering tasks, in which accessing external knowledge is necessary for answering the questions. This category is called outside-knowledge visual question answering (OK-VQA). A major step in developing OK-VQA systems is to retrieve relevant documents for the given multi-modal query. Current state-of-the-art asymmetric dense retrieval model for this task uses an architecture with a multi-modal query encoder and a uni-modal document encoder. Such an architecture requires a large amount of training data for effective performance. We propose an automatic data generation pipeline for pre-training passage retrieval models for OK-VQA tasks. The proposed approach leads to 26.9% Precision@5 improvements compared to the current state-of-the-art asymmetric architecture. Additionally, the proposed pre-training approach exhibits a good ability in zero-shot retrieval scenarios

    Simultaneous detection of Aeromonas hydrophila, and Escherichia coli in Rainbow trout (Oncorhynchus mykiss) by Duplex PCR

    Get PDF
    Rapid and accurate identification of microorganisms have a significant impact on strategies and fish health management programs. Hence, in this study a duplex PCR assay based on the 16s rRNA gene for simultaneous detection of Aeromonas hydrophila RTICC 1032 and Escherichia coli RTICC 2325 from pure cultures, and challenged fish tissues was performed and their results were compared with the results of single PCR assays for each bacterium. For this purpose, an experiment with three treatments including artificially infected with A. hydrophila, E. coli and a mixture of them with a control group was designed. Fish were injected intraperitoneally with 1 ml of sterile physiological saline containing 106CFU/ml of the corresponding bacteria. Samples were collected from liver, kidney and spleen 48 hrs post-injection. A duplex PCR based 16S rRNA genes was developed for the simultaneous detection of A. hydrophila and E. coli. The PCR reaction conditions were optimized to permit detection of organisms from agar plates and fish tissues in less than 8 hrs. Each of the two pairs of oligonucleotide primers exclusively targeted 16S rRNA gene of the specific microorganism. When duplex PCR assay was used to simultaneous detection of the pathogens in asymptomatic fish, spleen and liver were negative for A. hydrophila, whereas kidney was positive for two bacteria. Samples that were duplex PCR negative were also negative by the culture method. On the whole, the duplex PCR has advantages in terms of its accuracy, sensitivity, ease of use, time of length analysis and cost-effectiveness compared to the single PCR and traditional method

    RESIDUAL METAL CONCENTRATIONS IN ENHANCED COAGULATION WITH FERRIC CHLORIDE AND ALUM FOR TOC REMOVAL

    Get PDF
    Chemical coagulation with metallic salts has traditionally been used in water treatment for turbidity removal. However, coagulation is also capable of some degree of natural organic matter (NOM) removal, with NOM functioning as a precursor to disinfection by-products (DBPs) formation. Enhanced coagulation is thus introduced to most water utilities treating surface water. Jar-test experiments were conducted to compare the effectiveness of alum and ferric chloride in removing DBPs precursors from eight synthetic water samples, each representing a different element of the USEPA’s 3×3 enhanced coagulation matrix, and the residual metal (aluminum/iron) concentration in the treated water was assessed. Coagulant type influenced the removal of total organic carbon (TOC) and which was enhanced with increasing coagulant dose. For all the treated samples coagulation with ferric chloride proved to be more effective than alum at similar doses and the mean values of treatment efficiencies were 51% and 32%, respectively. Ferric chloride was therefore considered the better chemical for enhancing the coagulation process. The results of residual metal concentration measurements in treated water showed that iron and aluminum concentrations had been increased as expected but the quality of water concerning the residual metal deteriorated much more in cases of under-dosing. Despite expecting high residual Al and Fe concentrations under enhanced coagulation, metal concentrations were frequently remained low and were not increased appreciably

    RESIDUAL METAL CONCENTRATIONS IN ENHANCED COAGULATION WITH FERRIC CHLORIDE AND ALUM FOR TOC REMOVAL

    Get PDF
    Chemical coagulation with metallic salts has traditionally been used in water treatment for turbidity removal. However, coagulation is also capable of some degree of natural organic matter (NOM) removal, with NOM functioning as a precursor to disinfection by-products (DBPs) formation. Enhanced coagulation is thus introduced to most water utilities treating surface water. Jar-test experiments were conducted to compare the effectiveness of alum and ferric chloride in removing DBPs precursors from eight synthetic water samples, each representing a different element of the USEPA’s 3×3 enhanced coagulation matrix, and the residual metal (aluminum/iron) concentration in the treated water was assessed. Coagulant type influenced the removal of total organic carbon (TOC) and which was enhanced with increasing coagulant dose. For all the treated samples coagulation with ferric chloride proved to be more effective than alum at similar doses and the mean values of treatment efficiencies were 51% and 32%, respectively. Ferric chloride was therefore considered the better chemical for enhancing the coagulation process. The results of residual metal concentration measurements in treated water showed that iron and aluminum concentrations had been increased as expected but the quality of water concerning the residual metal deteriorated much more in cases of under-dosing. Despite expecting high residual Al and Fe concentrations under enhanced coagulation, metal concentrations were frequently remained low and were not increased appreciably

    Investigating the cost of wheat production in Iran and the effect of combine availability on harvesting cost

    Get PDF
    The aim of this study was investigated the cost of wheat production in Iran and the effect of combine availability on harvesting cost. Information of combine number and cost of wheat production in each province, for this period (2000 – 2006), attained from Ministry of Jihad-e-Agriculture of Iran statistics.  Data from variable costs such as land preparing, planting, cultivating, harvesting and land price in each province in each year was entered into computer. Comparisons between means of producing cost, specially harvesting cost, were carried out with use of SPSS15. To compare the mean of costs in each province Duncan test was used. The result showed that the cost of wheat harvesting in provinces has decreased with increasing the number of combine harvester in provinces. Therefore for decreasing the harvesting cost in Iran provinces it is necessary to distribute more combine harvester in provinces
    • …
    corecore