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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]

For 100 sunflower head, maximum and minimum diameters, thickness, height of the ground, and mass of all seeds on sunflower head (SH) for five conventional varieties were measured. To examine the correlation between maximum SH diameter and minimum SH diameter, SH thickness, SH height from the ground and SH seeds mass, linear regression method was used. Also SH diameter and SH thickness of four sunflower hybrids varieties were measured. Log-normal, Weibull and Generalized extreme value (G.E.V) distribution were used in order to model SH diameter and SH thickness distributions of all varieties and hybrids; also, Kolmogorov-Smirnov methods were used for comparison of all probability density. Results indicated that value of average of dimensions, geometric and arithmetic mean diameter, head height from the ground, and mass of the seeds on each head of Dorsefid and Sirena varieties were more and less than the other varieties, respectively. For all varieties, there was linear correlation between maximum SH diameter and minimum SH diameters, SH thickness and mass of seeds; while there wasn't any correlation between SH height and maximum SH diameter. Results showed that whenever skewness and kurtosis had positive values, Log-normal and G.E.V distribution had good performance and whenever skewness and kurtosis had negative values, Weibull and G.E.V distribution had good performance based on Kolomogrov-Smirnov methods. [ABSTRACT FROM AUTHOR]

The study was conducted to investigate some physical properties of celery seed at various moisture levels. The average length, width, thickness and 1000-seeds mass were 0.571, 0.429, 0.295 mm and 0.792 g, respectively, at moisture content of 5.24% (d.b). Length, width and thickness distributions of the seeds were modeled using Generalized Extreme Value, lognormal and Weibull distributions. Results showed that to model length of the seeds, lognormal distribution had the best performance while to model the width of the seeds Weibull distribution had the best performance. True density has increase from 892.02 to 931.42 kg/m3 when the moisture content increased from 5.24% to 20.25% (d.b). The angle of static friction increased from 28.45 to 39.66°, 25.15 to 34.84°, 19.57 to 27.07° and 16.72 to 19.720° for plywood, rubber, iron and galvanized metal, respectively, as the moisture content increases from 5.24% to 20.25% (d.b). The pouring angle of repose increased from 34.70 to 39.12°, 33.37 to 36.37°, 30.59 to 33.33° and 27.16 to 29.45° for plywood, rubber, iron and galvanized metal, respectively, as the moisture content increases from 5.24% to 20.25% (d.b). The Hele-Shaw angle of repose increased from 32.65 to 35.25°, 30.35 to 32.77°, 27.81 to 30.03° and 24.72 to 26.61° for plywood, rubber, iron and galvanized metal, respectively, as the moisture content increases from 5.24% to 20.25% (d.b). [ABSTRACT FROM AUTHOR]

Due to the success of air-jet in food and agricultural sciences, in order to eliminate a number of problems in mechanical methods of removing sunflower seeds from the head, a new method was invented based on impingement jets. In fact, the aim of presenting the air-jet impingement method was not to design this simple machine. But when we started designing the final machine, we realized that we need to take a step back and study the jet parameters in simple and static state. The effect of the seeds' location on sunflower head, reservoir pressure, the angle of impingement, nozzle diameter and the distance between the nozzle outlet and the surface of the sunflower head on the removed area of sunflower head in static conditions were examined. The regions removed by the impingement of the air-jet were photographed and the area of the removed regions was calculated. Response surface methodology was used for designing experiments for all three regions of sunflower head of ?Dorsefid? variety. Based on the obtained results of two varieties, on side, middle and central regions, removing seeds using 30°, 60° and 90° angle of impingement is advised respectively. The results indicated that the area of the removed regions was increased with the increase of the nozzle diameter and reservoir pressure. Also the removed area increased with the increase of the distance between the nozzle outlet and the surface of the SH at first, but then decreased. The optimal distance between the nozzle outlet and the surface of the SH ranges between 24 to 28 mm. [ABSTRACT FROM AUTHOR]

To design the planting, separating, threshing, sizing and packing machines for agricultural products, physical and mechanical properties of the products should be known. In this paper, some physical properties of red radish seeds were studied. Dimensional parameters, when moisture content equals to 5.65% based on dry bases (d.b), were measured using image processing technique. Effects of moisture content on gravimetrical and frictional properties of the seeds, including mass of single seed, 1000-unit seed, bulk density, true density, porosity, static coefficient of friction on various surfaces, and angle of repose based on pouring, Hele-Shaw, empting and filling methods were studied. Effects of volume of the container (150, 350, 550 and 750 mL) and height of fall on bulk density and porosity of the radish seeds when moisture content equals to 5.65% (d.b) were studied. Also length, width, thickness and mass distributions of radish seeds were modeled using Gamma, Generalized Extreme Value and Weibull distributions. Results showed that length, width and thickness of the seeds ranged from 0.660 to 0.900 mm, 0.524 to 0.763 mm and 0.490 to 0.759 mm, respectively. With increasing volume of the container from 150 to 550 mL, bulk density of the seeds increased; but with increasing volume of the container from 550 to 750 mL, bulk density of the seeds decreased. With increasing volume of the container from 150 to 550 mL, bulk density of the seeds increased; but with increasing volume of the container from 550 to 750 mL, bulk density of the seeds decreased. With increasing moisture content from 5.65 to 21.71% (d.b), bulk and true density of the seeds decreased from 694.807 to 654.889 kg/m3 and 1141.810 to 1057.795 kg/m3; but with increasing moisture content from 5.65% to 21.71% (d.b), 1000-unit mass increased from 6.98 to 7.17 g. [ABSTRACT FROM AUTHOR]

The study was conducted to investigate the effect of the moisture content on some physical properties of two varieties of melon seed. Results showed that when moisture content increased from 5.64% to 21.42% (d.b), three principle dimensions of the melon seeds and kernels of Samsori and Varami varieties increased; but the percentage of the chances and the rate of the changes for length, width and thickness had different values. True density of Samsori variety increased from 1182.611 to 1219.536 kg/m³ when the moisture content increased from 5.64% to 21.42% (d.b). True density of Varamin variety increased from 1132.058 to 1159. 370 kg/m³ when the moisture content increased from 5.32% to 21.02% (d.b). The angle of static friction of Varamin variety increased from 29.79° to 36.45°, 28.27° to 34.31°, 23.89° to 29.45° and 15.46° to 19.19° for wood, robber, iron and galvanized, respectively, as the moisture content increases from 5.32% to 21.02% (d.b); the corresponding values for Samsori variety increased from 20.71° to 26.63°, 23.95° to 30.79°, 19.51° to 25.09° and 13.81° to 17.76°, respectively. The pouring angle of repose of the Varamin variety increased from 43.79° to 52.63°, 42.27° to 50.51°, 41.75° to 47.00° and 39.11° to 43.87° for wood, robber, iron and galvanized, respectively, as the moisture content increases from 5.32% to 21.02% (d.b); the corresponding values for Samsori variety increased from 41.23° to 46.91°, 43.34° to 49.42°, 38.64° to 43.95° and 36.16° to 41.21°, respectively. [ABSTRACT FROM AUTHOR]

To design the planting, separating, threshing, sizing and packing machines for agricultural products, physical and mechanical properties of the products should be known. In this work some physical properties of parsley seeds were studied. Dimensional parameters including three principle dimensions, geometric mean diameter, equivalent diameter, arithmetic mean diameter, sphericity, volume, surface area, projected area, flakiness ratio and elongation ratio were measured using image processing technique. Also length, width and thickness distributions of parsley seeds were modeled using Gamma, Generalized Extreme Value and Weibull distributions. Gravimetrical properties including mass of single seed, thousand seed mass, bulk density, true density and porosity were measured. Effect of the container volume and fall height on bulk density and porosity were studied. Frictional properties of parsley seeds (static coefficient of friction on various surfaces and repose angle of based on bypouring, Hele-Shaw, empting and filling methods) were measured. Results showed that length, width and thickness of the seeds ranged (0.660 - 0.883mm), (0.524 - 0.752mm) and (0.490 - 0.744 mm), respectively. With increasing the container volume from 150 to 550 mL, bulk density of the seeds increased; but from 550 to 750 mL, it was decreased. True density and thousand seed mass of the seeds were 884.658 kg/m3 and 1.390 g. The values of friction coefficient on plywood, rubber, iron and galvanized surfaces were 27.35°, 24.17°, 19.31° and 14.77°, respectively. The values of filling and empting repose angles were 32.64° and 40.16°. [ABSTRACT FROM AUTHOR]

To design a new machine which removes the seeds of sunflowers based on air-jet impingement, picking force of five varieties of sunflower seeds was measured. Effects of the loading rate, sunflower head's diameter, the location of the seeds on the head and the number of the days after harvesting on picking force of seeds were studied. The tests were conducted one, two, three and four days after harvesting. Also theoretical air-jet impingement forces for four levels of nozzle diameter, four levels of jet temperature and eight levels of pressure of reservoir to which the jet were calculated. With the increase of the sunflower heads' diameter and the loading rate from 50 to 150 g/min, the values of the picking force increased. With the increase of the distance between the location of the seeds and the center of the head, the values of the picking force decreased. Comparison between the experimental results and the theoretical calculations indicated that removing the sunflower seeds using nozzles with 2 mm is not possible. Also when the supply pressure is less than 5 bar, nozzles with a 4 mm diameter cannot be used to remove the sunflower seeds from the heads. The results indicate that using a nozzle with a diameter of 6 to 8 mm and pressure of 6 to 8 bar seems to be suitable for separating the seeds from SH, though more studies are required. [ABSTRACT FROM AUTHOR]

Plantain seed is a commonly used medicinal herb, which has been used in traditional medicine. Physical properties are useful information for designers of processing equipment and for industrial processing of plantain seeds. Physical properties of plantain seeds were determined as a function of moisture content by image processing method. Several properties were obtained in the moisture range from 6.44% to 19.95% dry basis. The results showed that the length, arithmetic and geometric diameter of seeds increased from 0.300 to 0.330 mm, 0.222 to 0.276 mm, and 0.231 to 0.280 mm, respectively. The thousand-unit mass increased from 0.205 to a maximum value of 0.230 g, the surface area increased from 0.282 to 0.418 mm2, the porosity increased from 50.46% to 60.30%. The value of empting angle of repose was found to increase from 36.4° to 48.2° and the value of filling angle of repose was decreased gently from 38.9° to 36.8°. As moisture content increased from 6.44% to 19.96% (d.b), the static coefficient of friction for surfaces of iron, galvanized and wood showed an increase of 29.75%, 20.99% and 48.80%, respectively. The results showed that the bulk density decreased from 666.6 to 526.9 kg/m3 and the true density decreased to a minimum value of 1310.6 kg/m3 at moisture content of 15.06% (db). [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]

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]

In order to study the effects of gamma radiation on some physical properties of squash (Cucurbit pepo. L) seed, five irradiation doses (25, 50, 75, 100 and 200 GY) have been used. Some physical properties, including dimensional properties (length, width, thickness, geometric mean diameter, sphericity, volume, surface area, projected area, flakiness ratio and elongation ratio), mass, 1,000 seeds mass, bulk density, true density and porosity of gamma irradiated squash seeds were measured. Statistical indices including maximum, minimum, average, variance, skewness and kurtosis, for dimensional properties and mass of the seeds were calculated. Results revealed a significant raise in hollow seeds number by increasing gamma irradiation dose from 5% for 25 GY to nearly 100% for 100 and 200 GY. On the other hand, length, width, thickness, mass of single seed, 1,000 seeds mass and porosity showed an increase followed by a decrease with the increasing gamma irradiation dose. With the increasing gamma irradiation dose, true and bulk densities were found to decrease from 338.41 kg m-3 to 214.01 kg m-3 and 420.16 kg m-3 to 256.12 kg m-3, respectively. In 100 and 200 GY all seeds were hollow and very small, therefore dimensions and mass of these seeds were not measured. [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]

Knowledge of agricultural seeds' physical properties has significant importance for machinery and processing equipment design. Physical properties of flixweed (Descur ainia sophia L.) seeds were determined as a function of moisture content. Several properties were studied in the moisture range from 5.28 to 17.53% dry basis. Also, probability distribution of seeds' principal dimensions were modeled by Gamma, Generalized Extreme Value, Lognormal, and Weibull functions. With increasing moisture content from 5.28 to 17.53%, properties including; length, width, thickness, geometric and arithmetic mean diameter, sphericity, specific surface area, volume, and projected area showed no specific trend. In contrast, the surface area increased from 6×10-7 to 1×10-6 m2. The bulk and particle density decreased from 696.61 to 542.51 kg·m-3, and 1217.50 to 1189.02 kg·m-3, respectively. The porosity increased from 42.78 to 54.37%. The maximum external static angle of friction belonged to wood at all moisture content levels, followed by the iron and galvanized surfaces. At all moisture levels, the emptying angle of repose was more than the filling one. [ABSTRACT FROM AUTHOR]

One of the most critical challenges of determining tiny seeds' engineering properties is their dimensions. In the present study, a method based on digital image processing was employed to investigate the moisture content's effect on geometric properties of summer savory, basil, cress, and ajowan seeds. Also, the gravimetrical and frictional properties of the seeds were measured. Gamma, Generalized Extreme Value, and Weibull distributions were used to model the probability frequency distribution of the seeds' length, width, and thickness. This research indicated that the application of the image processing technique could be an excellent method to measure dimensional parameters of tiny seeds. Results showed that, with an increasing moisture content of seeds, the 1000-seed mass increased for basil, cress, and ajowan seeds; but, summer savory seeds showed that increasing-decreasing trend. For all four plant spices, increasing moisture content will result in the bulk density decrement. The particle density of summer savory, basil, and cress seeds decreased due to moisture content increment. However, the particle density of ajowan seeds increased with increasing moisture content. Results of measuring the angle of friction on iron, wood, and galvanized surfaces showed that, in most cases, the angle of friction increased by increasing moisture content. Also, except for the filling angle of repose of summer savory, increasing trends were observed for the emptying and filling angle of repose due to moisture content increment. [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]

Information on physical properties of broiler chickens diets is not available in literatures and such information is important for design and construction of poultry equipments. Some physical properties of starter, grower and finisher diet of broiler chickens, namely: gravimetrical (bulk density, true density and porosity) and frictional properties (coefficient of friction filling angle of repose, empting angle of repose and pouring angle of repose) were studied. Effect of height of falling diets to the containers at 150, 250 and 350 mm and volume of the containers at 500, 600, 1,100 and 2,000 mL on bulk density and porosity of diets were studied. Results indicated that true density of the starter; grower and finisher diets were 1,442.574, 1,512.694 and 1,541.320 kg m³, respectively. A comparison between the three levels of height of falling for three diets indicated that with increasing height of falling, bulk density were increased and porosity were decreased. The coefficient of friction of starter, grower and finisher diet on different surfaces changed from 18.033 to 26.743°, 18.083 to 27.193° and 18.293 to 27.570°, respectively. The values obtained for pouring angle of repose of starter diet on iron, plywood and galvanized surfaces were 34.40°, 36.05° and 30.22°, respectively. The corresponding values for grower and finisher diets were 38.71°, 39.62°, and 33.72° and 36.66°, 38.21° and 33.62°, respectively. [ABSTRACT FROM AUTHOR]