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Biofumigation for the Control of Vegetables Soilborne Pathogens in Some non-Temperate Climate Countries
Get PDFSoil-borne pathogens (SBPs) significantly reduce the yield and quality of crops worldwide. In the past, their control was principally accomplished by using soil fumigants such as methyl bromide (MB). However, this fumigant which is a powerful ozone-depleting substance, has completely been phased out under the Montreal Protocol (MP). New chemicals and non-chemical alternatives to MB, including biofumigation, have been actively researched, developed, and commercially adopted worldwide. This review seeks to provide the status of biofumigation for the control of SBPs in some non-temperate climate zones referred to in this paper as Article 5 countries or developing countries according to the Montreal Protocol (MP) classification. The review will first define “the non-temperate climate zone,” list the countries belonging to this zone, focus on the role and importance of the MP in phasing-out MB, and in searching and commercially adopting alternatives including biofumigation to this fumigant. It also describes the biofumigation techniques reported and used, reports its efficacy/inefficacy to manage SBPs in some non-climate temperate countries, insists on the place it must have in an IPM program to increase its efficacy, and finally, lists the collaboration and the research needed to further develop and commercially adopt this technology in non-temperate climate countries
Comparison of Speech Quality and Intelligibility Assessments in University Classrooms
Get PDFEstimates of speech quality and intelligibility for three university classrooms of small, medium and large sizes are presented. The quality and intelligibility of speech were assessed by objective methods using binaural room impulse responses, measured at 5-6 points of the premises. The measures of speech quality were log-spectral distortion (LSD), bark spectral distortion (BSD) and perceptual evaluation of speech quality (PESQ), and the objective measure of speech intelligibility was the speech transmission index (STI).
Among the quality measures considered, only BSD is shown to be highly correlated with STI measures for all three classrooms. In this case, correlation coefficient R varies from minus 0.6 for a small room to minus 0.98 for a large room. The close relationship between PESQ and STI is observed only in the case of a large classroom (R = 0.96-0.99), and the LSD measure was found to be uncorrelated with STI for premises of all sizes. The obtained results can serve as a justification for the use of BSD instead of STI, and vice versa, in the acoustic examination of classrooms of different sizes
Transformer Oil Generation and Regeneration Techniques Based on Recent Developments (A Review)
Get PDFWith regard to the wide application of Transformer Oils (TO) as an energy stream on an industrial scale with fast progress towards green TO generation and regeneration technologies, the current review takes into investigation the TO generation industries based on the screening step of industrial projects by Iranian evaluator teams of in-charge organizations. The present review encompassed the TO generation and regeneration technologies from traditional, typical, and recently developed practices in this regard. The technologies extended to introduce green TO generation practices in connection with fossil fuel resources. By the way, a comparison has been done based on technologies posed for TO with the used motor oil reprocessing techniques and used lubricant oil regeneration technologies. To sum up, the current review comprised basic knowledge to select the best technologies for decision-making models in future industrial developments. The prominent achievement of the current review can be mentioned to the aggregation of industrial data for further processing in decision-making theory, criteria, and alternatives selections
The Joint Application of Diagenetic, Petrophysical and Geomechanical Data for Selecting Hydraulic Fracturing Candidate Zone: A Case Study from a Carbonate Reservoir in Iran
Get PDFThe more comprehensive information on the reservoir properties will help to better plan drilling and design production. Herein, diagenetic processes and geomechanical properties are notable parameters that determine reservoir quality. Recognizing the geomechanical properties of the reservoir as well as building a mechanical earth model play a strong role in the hydrocarbon reservoir life cycle and are key factors in analyzing wellbore instability, drilling operation optimization, and hydraulic fracturing designing operation. Therefore, the present study focuses on selecting the candidate zone for hydraulic fracturing through a novel approach that simultaneously considers the diagenetic, petrophysical, and geomechanical properties. The diagenetic processes were analyzed to determine the porosity types in the reservoir. After that, based on the laboratory test results for estimating reservoir petrophysical parameters, the zones with suitable reservoir properties were selected. Moreover, based on the reservoir geomechanical parameters and the constructed mechanical earth model, the best zones were selected for hydraulic fracturing operation in one of the Iranian fractured carbonate reservoirs. Finally, a new empirical equation for estimating pore pressure in nine zones of the studied well was developed. This equation provides a more precise estimation of stress profiles and thus leads to more accurate decision-making for candidate zone selection. Based on the results, vuggy porosity was the best porosity type, and zones C2, E2 and G2, having suitable values of porosity, permeability, and water saturation, showed good reservoir properties. Therefore, zone E2 and G2 were chosen as the candidate for hydraulic fracturing simulation based on their E (Young’s modulus) and ν (Poisson’s ratio) values. Based on the mechanical earth model and changes in the acoustic data versus depth, a new equation is introduced for calculating the pore pressure in the studied reservoir. According to the new equation, the dominant stress regime in the whole well, especially in the candidate zones, is SigHmax>SigV>Sighmin, while according to the pore pressure equation presented in the literature, the dominant stress regime in the studied well turns out to be SigHmax>Sighmin>SigV.
Thermal Performance Improvement and Contamination Control Strategies in an Operating Room
Get PDFOperating room is a cleanroom that provides thermal comfort and good indoor air quality (IAQ) to support the surgery process. The heating, ventilation, and air conditioning (HVAC) system plays a critical role for the health protection regarding to IAQ, i.e., thermal performance, air changes per hour, pressurization, filtration, air distribution, etc. However, HVAC system in the operating room is operated for 24 hours year-round with intensive energy consumption. Energy-efficient approaches for the HVAC system is also quite challenging in term of contamination control to meet the standards specifications. In this study, a full-scale operating room was carried out through field measurements and numerical analysis extensively. Computational Fluid Dynamic (CFD) simulation has been carried out and verified with field measurement data. Thermal comfort performance along with temperature distribution and velocity profile have been simulated extensively. The energy-efficient approach by reducing the face velocity of the HEPA filter was examined which is done by reducing the velocity from 0.4, 0.3, 0.2 (m/s) for energy-saving concern but still need to meet the thermal performance and minimum contamination control requirement. The results reveal how the potential of HVAC systems to control air contamination, a comfortable thermal environment for occupants and the possibility of energy-efficient approaches in the operating room
Global Warming and Loss of Bearing Capacity of Permafrost: An Experimental Study on the Effects of Freezing/Thawing Cycles on a Silty Soil
Get PDFOne of the major effects of global warming is the thawing of permafrost. This phenomenon has several consequences on the affected environments, such as the loss of soil bearing capacity, the beginning of the seasonal cycles of freezing/thawing and an increase in the frequency of occurrence of natural hazards.This paper focuses on the loss of soil bearing capacity. A preliminary experimental study was carried out to understand and quantify the changes in the behaviour of a silty soil subjected to a freezing / thawing cycle through a series of laboratory tests. After the soil used for the lab tests was characterised, many shear tests and oedometric tests were performed before, during and after freezing. The geotechnical parameters were deduced from the oedometric curves and Mohr-Coulomb diagrams obtained. The comparison of the results made it possible to observe the evolution of the soil parameters, i.e. the internal friction angle, the cohesion, and the oedometric curves.All tests were carried out according to Swiss standards for laboratory testin
A Transient Two-dimensional CFD Evaluation of Indoor Thermal Comfort with an Intermittently-operated Radiant Floor Heating System in an Office Building
Get PDF To provide excellent thermal comfort in an energy-efficient manner, the radiant floor cooling and heating system has become an attractive technology. In this work, an intermittently-operated radiant floor heating system combined with a ventilation system for use during the weekdays is proposed via a transient two-dimensional computational fluid dynamics model that takes into account the variation of the indoor heat gain. Additionally, intermittent controls based on the minimum outdoor air temperature and the average water supply and return temperature are proposed. Six specifically-designed outdoor air temperature values ranging from -15oC to 15oC are taken as examples to evaluate the thermal comfort performance using the operative temperature and local thermal discomfort criteria, including the vertical air temperature, floor temperature, and radiant asymmetry. Meanwhile, the percentages dissatisfied induced by the local discomfort parameters above were analyzed.. Results show that for the case with a minimum outdoor air temperature of -14.2 oC, the earlier shut-off of the water supply (e.g., 18:00) cannot contribute to maintaining a comfortable environment at 7:00. To eliminate the effect of the indoor heat gain, a water supply shut-off after 20:00 and the pump starting to recirculate water in the concrete slab at 00:00 are encouraged in the case of an insufficient indoor heat gain during the next daytime. The maximum operative temperature commonly occurred between 4:00-6:00 p.m. A trade-off between the percentages dissatisfied and the operative temperature is finally identified. The control strategy of the shut-off of the water supply for two hours at noon and at least four hours during the nighttime is ultimately obtained to yield the acceptable thermal comfort performance in the intermittent operating mode of a floor heating system while effectively reducing energy consumption
Energetic Analysis in a Spray Drying Process
Get PDF The present work aims in evaluate the installation of an equipment of spray drying, by psychrometry technique, analyse the power sources consumption and relates with the productivity of the equipment, by energy auditory. This work consists in comparing the evaporation capacity of a 750 kg/h of water spray dryer and the amount of water that comes from atmospheric air, where the equipment consumes 160 kWh and 80 kg of LGP/h. Therefore, this work demonstrates that to project a spray dryer it must be analysed these water mass values in atmospheric air and be contemplated a dehumidifier in order to prevent so significant and different losses in different periods of the same day
The Latest Reports in Managing Acidic Sludge of Used Motor Oil Reprocessing Industries
Get PDFUsed Motor Oils Recycling (UMOR) can be fulfilled in different ways depending on the quality and quantity of the fresh oil and the quality of the collected UMO. The Acidic Sludge (AS) is a byproduct of UMOR with hazardous effects and impacts on the environment. It yields 0.15 of each barrel (220 liters) of UMOR operation. The valid and relevant databases were used to discover the latest reports in managing the AS of UMOR operation. The findings of the current review were oriented towards the physical-chemical backbone of AS and its industrial exploitation. The chemical structure of AS was highlighted by a glance view in the recent reports. To sum up, it was recommended to utilize this valuable byproduct in many industrial applications as an additive
A Numerical Method with Shifted Chebyshev Polynomials for a Set of Variable Order Fractional Partial Differential Equations
Get PDFIn this paper, a high-efficiency numerical algorithm based on shifted Chebyshev polynomials is given to solve a set of variable-order fractional partial differential equations. First, we structure the differential operator matrix of the shifted Chebyshev polynomials. Then, we transform the problem into solving a set of linear algebraic equations to obtain the numerical solution. Moreover, a step of error correction is given. Finally, numerical examples are given to show the effectiveness and practicability of the proposed method