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Three main dimensions of nut and kernel of almonds were measured. Then some dimensional properties of nut and kernel were calculated. Effect of the moisture content on bulk density, true density, porosity and coefficient of friction of kernels and nuts were studied. Angle of repose on iron, plywood and galvanized sheet were measured. Also in order to examine the correlation between two dimensions of kernels and nuts and correlation between one dimension of nuts and similar dimension of kernels, linear and quadratic regression were used. Length, width and thickness distributions of nuts and kernels were modeled using normal, log normal, Weibull and Generalized Extreme Value distributions. For modeling other dimensional properties, only Generalized Extreme Value was used. The estimated parameters of the PDF for three main dimensions of nuts and kernels indicated that G.E.V was best fit. With increasing moisture content of the kernels from 4.20% to 29.64% (w.b.), true density and porosity were increased from 939.629 to 1,077.428 kg m-3 and 37.704% to 57.088%, respectively; and bulk density was decreased from 585.350 kg m-3 to 462.343 kg m-3 . When the moisture content of the nuts increased from 4.03% to 28.13% (w.b.), true density and porosity were increased from 1,025.124 kg m-3 to 1,149.700 kg m-3 and 38.562% to 56.55%, respectively, and bulk density was decreased from 629.81 kg m-3 to 499.532 kg m-3 . Values of coefficient of friction on all surfaces were increased with increasing moisture content. [ABSTRACT FROM AUTHOR]

Information on physical properties of virgin olive fruit, especially those grown in Iran,arenot available in literatures. Some physical properties of Mari variety of virgin olive fruits, namely: dimensional properties (length, width, thickness, arithmetic mean diameter, geometric mean diameter, sphericity, volume of the fruit, surface area and projected area), gravimetric properties (unit mass of fruit, 1,000 fruit mass, bulk density, true density and porosity), frictional properties (angle of repose and coefficient of friction), modeling dimensional properties and mass (using normal distribution) were studied. Also sphericity, volume, surface area and projected area were calculated using different theoretical equations. Length, width and thickness of fruits ranged from 18.46 mm to 27.63 mm, 15.80 mm to 21.99 mm and 14.77 mm to 20.33 mm, respectively. Bulk density of fruits increased from 590.78 kg m-3 to 646.51 kg m-3 as the volume container increased from 500 mL to 2,000 mL and true density of 1,059.14 kg m-3 were obtained. The highest value forangle of repose and coefficient of friction amongplywood, rubber, iron and galvanized surfaceswererecorded for iron surface and the lowest value was recorded for galvanized surface. [ABSTRACT FROM AUTHOR]

For designing the dehulling, separating, threshing, sizing and planting machines for sunflower, physical and mechanical properties of sunflower seeds should be known. In this work some physical properties of three varieties of sunflower seeds, distance between the adjacent seeds on the sunflower head (SH), length, width, thickness, mass of the individual seeds, 1000- seeds mass, and changing these parameters with location of seeds on SH were measured. Then shape properties, including geometric mean diameter, sphericity, surface area, projected area and volume of the seeds were calculated. Variations of the shape properties of the seeds on the SH were studied. Statistical indices for dimensional and shape parameters were calculated. For Mikhi, Sirena, and Songhori varieties, true and bulk densities, porosity, angle of repose on wood and galvanized surfaces were calculated by using standard methods in the moisture of 9.15, 5.26 and 5.62% (w.b.), respectively. The distribution of distance between adjacent seeds on SH was modeled by using three continuous statistical distributions namely Normal, two-parameter Log-normal and two-parameter Weibull distribution. Size and mass of seeds were modeled with two-parameter Weibull distribution. The parameters of the probability density functions (PDF) were estimated, then evaluated, and the predictive performances of the models were compared. Log likelihood goodness of fit test was used to test how well different PDFs work for prediction of the distance between seeds on sunflower head, size and mass of seeds. The results for three varieties showed that when the distance between locations of the seed from center of the sunflower head increased, size, shape properties and mass of seed, increased, too. The values of true and bulk density, porosity and angle of repose on wood and galvanized surfaces for Mikhi variety were 497.500 kg/m³, 331.027 kg/m³, 33.46%, 25.08° and 22.23°, for Sirena were 580.368 kg/m³, 422.015 kg/m³, 27.28%, 26.80° and 23.86°, and for Songhori were 471.746 kg/m³, 319.346 kg/m³, 32.30%, 24.39° and 21.70° respectively. Modeling result for the distance between adjacent seeds on SH showed that, Log-normal distribution model fits the empirical probability density well and two-parameter Weibull distribution had worst performance for prediction. Also modeling result for the distance between adjacent seeds on showed that whenever Skewness and Kurtosis had negative value, Weibull distribution was best fit. Statistical analyses for dimensional properties and mass showed that in most cases, both Skewness and Kurtosis had negative values. Therefor for modeling dimensional properties and mass, Weibull distribution was used. [ABSTRACT FROM AUTHOR]

Increasing energy efficiency in water distribution systems is one of the most important aspects of a sustainable water infrastructure. Additionally, providing this energy from renewable sources is an essential step towards a cleaner production in energy infrastructures. Therefore in this paper, an optimization model is developed to minimize the energy consumption of a water-energy microgrid system. A day-ahead economic dispatch model is developed to minimize the daily cost of energy in the water-energy microgrid. The energy consumption of water system is minimized using tank's and pump's scheduling and operation, hydraulic factors, and daily demand. Particularly, the electricity consumption of the pump is minimized by adjusting its head gain and flow rate via a variable speed. The energy unit is composed of an aggregated conventional power generation, solar photovoltaic, wind generation, and battery energy storage system. To offer a global optimum for the proposed non-linear programming formulation, bivariate piecewise linear approximation is used to linearize the pump's power consumption and gain, and conservation of energy-mass. In addition, univariate piecewise linear approximation is used to linearize the energy consumption function of conventional power generation systems. The optimization results of the mixed integer linear programming and mixed integer non-linear programming formulations for the studied water-energy microgrid system are compared and discussed. These models are developed to concurrently minimize the electricity consumption of a micro water-energy distribution network in two scenarios of (1) standalone water distribution system operation and (2) an integrated islanded micro water-energy system with electrical loads. • Energy consumption of standalone micro water system is formulated. • Co-optimization of energy and water demand in water-energy microgrid is studied. • Via piecewise linearization, nonlinear functions presented as linear approximates. • Unit commitment problem was formulated for distributed generation units. • A microgrid with battery storage and renewable sources is considered. [ABSTRACT FROM AUTHOR]

• An integrated state-estimation of a combined water-energy system is proposed. • Via 3-tier state estimation in water system, computational issues are resolved. • False data injection is identified via an integrated bad data detection framework. • Source of false data is determined via an integrated bad data detection model. Recent studies have shown indisputable evidence indicating water and energy networks are two interdependent cyber-physical networks and should be operated cooperatively to maximize their efficiency and resiliency. However, current state-estimation models of water and energy infrastructures are implemented independently in their respective control centers. Such independent state-estimation in energy or water network might not be able to detect false data injections in the other network. In this paper, an integrated state-estimation framework is proposed to process the consistency of the data and estimate the parameters of a combined water and energy network. Compared to standalone state-estimation, an integrated framework proposed in this work makes it more difficult for the attackers to launch stealthy false data injections, as more parameters are involved in the state-estimation that need to be modified for a successful attack. The findings of this research confirm that by accounting for interlinks between hydrological and energy systems, the security of both systems will be improved. The interconnection between the state variables and measurements of the water-energy network is reflected in the energy consuming components of the water system, and is achieved through the measurements of pump's active power consumption in the proposed integrated estimation framework. The framework includes Newton's iterative method for an alternating current (AC) state-estimation procedure for the energy network. The state-estimation of the energy network includes the estimation of voltages using measured parameters of the energy network such as active/reactive power flow/injection or voltages. Moreover, a three-tier state-estimation process based on Newton's iterative method for the water network is contemplated to attain nodal heads, nodal demands, and the flow rate of the pipes without pumps. An integrated bad data detection algorithm is also supplemented to the proposed framework to detect potential bad data in water distribution system or energy network and enhance the resilience of the integrated water energy systems. [ABSTRACT FROM AUTHOR]

• Dynamic economic dispatch of a water-energy microgrid with intelligent thermal management. • Optimizing the energy consumption of pumps in water distribution network. • Considering occupants' temperature comfort range. • Adding thermal equilibrium of buildings to dynamic economic dispatch. • Use of renewable energy sources and energy storage in water-energy microgrid. In this paper, a mixed integer nonlinear programming formulation is proposed to intelligently dispatch the distributed generators, manage buildings' thermal energy, and support the water demand in an islanded water-energy microgrid. To optimize the demand of water distribution system, pump's nonlinear scheduling and hydraulic factors, and daily water usage of buildings are added to the formulation. In addition, thermal management of electric chillers considering customers' comfort level and outside temperature forecast was formulated. For a summer cooling schedule, it is shown that adjusting the indoor temperature settings at 20–25 °C for both occupied and unoccupied hours offers the lowest daily operation cost and peak demand charges. A fixed temperature setting of 25 °C during the occupied and unoccupied hours results in a lower daily cost and demand charges than a wide temperature setting of 15–30 °C. Lowest daily costs and electricity demand can be achieved within the proposed integrated water-energy microgrid with optimal water demand and building thermal energy management. By incorporating the water system constraints in the optimization model, hourly cost savings up to $150 can be achieved. In addition, incorporating building's thermal management in the proposed economic dispatch model can result in up to $20 hourly energy saving in the water-energy system. [ABSTRACT FROM AUTHOR]

• Energy consumption of a standalone micro water system is optimized. • Energy consumption of an islanded a micro water-energy system is optimized. • Random behavior of renewable energy sources is considered for the energy system. • Battery energy storage charging/discharging is used in the micro energy system. • Variable speed and quadratic functions for the head of the pumps are considered. Water and energy systems are interdependent. However, at national and international levels, energy and water systems have been designed individually. To optimize the use of energy resources and have a more sustainable energy processes, a new formulation is proposed in this paper to optimize the energy consumption of water-energy systems at a community scale. More specifically, single-objective, bi-level, and co-optimization models are developed to minimize the energy consumption of a micro water distribution network concerning three scenarios: (1) standalone operation; (2) integrated with a grid-connected micro energy system with no storage unit; and (3) integrated with an off-grid micro energy system with storage units. In all conditions, a mixed integer nonlinear programming formulation is used to solve the optimization problems. Pump operations with varying statuses, flow rates, and speeds are contemplated to formulate the energy consumption of the micro water, considering a quadratic function for the pump's energy head changing with flow rate. The micro water network is designed based on a diurnal pattern of water demand for a network including 1 reservoir, 1 water tank, 6 nodes, and 2 pumps. The micro energy system includes a microgrid with a combined heat and power plant (CHP), diesel (DS) generator, natural gas (NG) generator, renewable sources (solar and wind), and energy storage units. Several case studies are carried out to compare the performance of developed optimization models. [ABSTRACT FROM AUTHOR]

An impingement jet method was employed for extracting of sunflower seeds from sunflower heads (SHs). The method was based on holding SHs with a rotating plate and extracting the sunflower seeds with the help of pressurized air-jets. Artificial neural networks (ANNs) and response surface methodology (RSM) were used to model the effects of operational parameters of impingement air-jet on performance of preliminary model of the remover machine. The operational parameters were diameter of nozzle (ND), angle of impingement (AI), distance between nozzle outlet and sunflower head (DBNS), air pressure (AP) and rotational velocity of sunflower head (RV). The final ANN model, 3-5-1, successfully modeled the relationship between three operational parameters, ND, AI and RV with removing performance of machine (RPAJSSR) with R2of 0.98 and T value of 0.96. The RSM method was applied for three different locations of SHs at the optimum AP of 7 bar. The maximum value of RPAJSSR, (57%) was obtained for ND of 8 mm, AI of 30°, DBNS of 20 mm and RV of 10 rpm at side region of SH (SRSH). Also, the minimum value (4.49%) belonged to ND of 4 mm, AI of 30°, DBNS of 20 mm and RV of 15 rpm for central region of SH (CRSH). [ABSTRACT FROM AUTHOR]

In order to eliminate some problems of traditional and mechanical methods of separating sunflower seeds from the receptacles, a new method based on impingement jets was innovated. The effect of the seeds' location, reservoir pressure, nozzle diameter, and the distance between the two nozzles on the separating area of sunflower receptacle, in three different states including, static, linear movement of sunflower receptacle, and rotational movement of nozzles were examined. Also theoretical areas of covered region by the two nozzles in the three different states were calculated. The regions separated by impingement of the air-jet were photographed and the area of the separated regions was calculated based on image processing technique. Also, for the three states, power consumption of compressor was calculated. Moreover, in each state, response surface methodology was used to find the five best optimized points. In the static state, maximum and minimum values of area of separated regions in the central, middle, and side region of sunflower receptacle were equal to 2.63 and 1.39, 3.83 and 1.96, and 4.02 and 2.12 cm2, respectively. In the linear movement state, maximum and minimum values of area of separated regions in the central, middle, and side region of sunflower receptacle were equal to 9.78 and 5.72, 16.19 and 10.02, and 17.43 and 11.15 cm2, respectively. The corresponding values for rotational movement state were 9.33 and 5.14, 128.98 and 86.12, and 241.89 and 157.65 cm2, respectively. Obtained results by variance analyzing showed that in all three states and in each region, effects of independent input factors were significant at probability level of 1%. Also in all tests, no seed was observed to be damaged due to air-jet impinging. [ABSTRACT FROM AUTHOR]

Although water and energy systems are interdependent, they are still designed individually due to their complexity. This paper proposes a multiple input multiple output (MIMO) model predictive control (MPC) for demand management of an integrated water distribution system (WDS) supplied by an islanded microgrid (MG) system, offering an additional opportunity for energy-saving at the WDS. This strategy benefits the island and remote communities, which have limited access to the centralized electric grid. The existing literature either used an open-loop approach for energy management of water-energy microgrids or ignored the interconnected nature and MIMO nature of these systems. Compared to that, the proposed closed-loop energy management system is developed to address the detailed dynamics of assets, the inherent interconnections between water and energy networks, and to provide resilience as well as energy saving and demand management capabilities. The integrated MPC algorithm is designed in discrete time, utilizing a state-space model and sequential quadratic programming (SQP) as the solution method. Considering the intensive use of electricity by the pumps in WDS, their energy consumption is accommodated by an islanded microgrid system that incorporates a diesel generator, renewable energy sources (wind and solar), and a battery bank that serves as an energy source and a storage device. The proposed approach is investigated using base water demand from a real-world community, Telford, in Pennsylvania. Several case studies, such as variations in renewable energy contributions and increments of the control actions, are carried out to demonstrate the feasibility and reliability of the integrated MPC to provide efficient water and energy demand management concurrently. • Model predictive control algorithm of the interconnected water-energy is developed. • The full dynamics of energy-consuming assets in the water system are considered, including quadratic pump relations. • Effect of the renewable energy variations on the 24-hr energy dispatch is studied. • Multiple optimal configurations result in up to $360k/year savings, reduced carbon footprint, and smoother control. • The developed framework is applied in a Telford, PA case study, showcasing its real-world implementation. [ABSTRACT FROM AUTHOR]

Some physical and mechanical properties of sunflower seeds were studied. The measured parameters were linear dimensions, thousand grain mass, geometric mean diameter, sphericity, surface and projected area, volume, shape parameters (such as flakiness ratio and elongation ratio), true and bulk densities, porosity, angle of repose and static coefficient of friction of the Shamshiri variety in the moisture range from 6.3 to 20% (w.b.) using standard methods. Average rupture force, deformation and absorbed energy at rupture point of the sunflower seeds under compression as well as the extent of physical damage to seeds due to impact were also determined over a range of moisture contents between 1.8% and 20.3% (w.b). The results showed a variation of 14.32 to 31.00 mm for length, 4.73 to 9.82 mm for width and 2.36 to 6.67 mm for thickness of sunflower seeds. The values of the thousand grain mass, seed volume, true density, bulk density and porosity of sunflower seeds were between l49.81-167.77g, 99.05-628.9 mm3, 444.39-521.78 kg/m3, 269.06-275.57 kg/m3 and 39.09-17.18% respectively. The rupture force, deformation, and absorbed energy increased with increase in moisture content from 1.8 to 14.5%, while decreased with further increasing of moisture content from 14.5 to 20.3%. The mean value of percentage of physically damaged seeds increased from 2.75 to 10.81% with increasing the impact velocity from 40.8 to 62.3 m/s. In both impact orientations, the total damaged seeds increased with increase in impact velocity for all moisture contents of seeds. [ABSTRACT FROM AUTHOR]

To design a sunflower machine for removing seeds from sunflower head (SH) based on air-jet impingement, preliminarily model of such machine was designed, constructed and evaluated. Effects of the seed location, angle of impingement, distance between nozzle outlet and sunflower head, and rotational velocity of sunflower head on percentage of extracted seeds were examined. In order to examine the effects of air-jet parameters on percentage of removed seeds in different locations of seed on sunflower head, sunflower heads were divided into three regions, namely central region, middle region and side region. Results indicated that in all three regions, with increasing rotational velocity from 10 to 30 rev/min, percentages of removed seeds from the SH decreased. Results also indicated that in all three regions, with increasing distance between nozzle outlet and SH surface from 10 to 20 mm and decreasing distance between nozzle outlet and SH surface from 40 to 20 mm, percentage of removed seeds from the SH by air-jet increased. Results indicated that in side region, with decreasing angle of impingement from 90% to 30%, of removed seeds from the SH by air-jet increased and in middle and central regions, with increasing angle of impingement from 30° to 60° and decreasing angle of impingement from 90° to 60°, percentages of removed seeds from the SH by air-jet increased. Also in all tests, no seed damaged due to air-jet impinging was observed. [ABSTRACT FROM AUTHOR]

Due to the success of air-jet application in food and agricultural sciences, a new method was invented based on the impingement jets to eliminate some problems presented in mechanical methods of removing sunflower seeds from the head. When the sunflower head had linear velocity and the nozzle was fixed, the effects of the seeds’ location on the sunflower head, reservoir pressure, nozzle diameter, linear velocity of the sunflower head, and the distance between the nozzle outlet and the surface of the sunflower head on its removed area were examined. The regions removed by the impingement of the air-jet were photographed, and the area of the removed regions was calculated based on the image processing technique. The results showed that the area of the removed region increased with increasing the nozzle diameter, reservoir pressure, and distance between the nozzle outlet and sunflower head; also, the area of the removed region increased with decreasing the linear velocity of the sunflower head. The maximum value of the area of the removed region in all regions was obtained when the linear velocity, nozzle diameter, reservoir pressure, and distance between nozzle outlet and sunflower head were equal to 1 cm sec-1, 8 mm, 800 kPa, and 30 mm, respectively. The minimum value of the area of the removed region in all regions was obtained when the linear velocity, nozzle diameter, reservoir pressure, and distance between nozzle outlet and sunflower head were equal to 3 cm sec-1, 4 mm, 600 kPa, and 10 mm, respectively. [ABSTRACT FROM AUTHOR]