Showing 31 results for Performance
M. R. Akbari, H. Kermanshahi, G. A. Kalidari,
Volume 8, Issue 3 (10-2004)
Abstract
This experiment was conducted to evaluate the effects of adding acetic acid to drinking water on the performance and ileal microorganisms of broiler chickens. In a completely randomized design with 5 treatments and 5 replicates, 300 day-old commercial mail broiler chicks (ROSS) were divided into 25 groups, 12 chicks per group. Each of the five levels of acetic acid added to drinking water (0.0, 0.1, 0.2, 0.3, and 0.4%) were given to five replicates for a period of 21 days. All groups were fed a practical corn-soybean based diet. During the experiment, chickens were not fed any antibiotics or coccidiostats. The diet formulation for all groups was the same. At 14 and 28 days of age, one chicken of each replicate was weighed and killed by cervical dislocation. Ileal contents were collected and used for microbial evaluation. At 49 days of age, one bird from each pen was killed to weigh gastrointestinal tract, liver, pancreas and abdominal fat. The number of total aerobes and colliforms per gram of ileal contents were enumerated on the appropriate bacteriological media. There was no significant difference in feed intake, weight gain, feed to gain ratio, live body weight, gastrointestinal tract, abdominal fat, liver and pancreas weights (p>0.05). Also, the differences among treatments for total aerobe and coliform counts were not significant (p>0.05). Under the conditions of this study, addition of acetic acid as an organic acid into drinking water at the levels used could not affect the performance and ileal microbial counts of chickens.
S.m.a. Jalali Hajiabadi, S.a.h. Abolghasemi, A.r. Jafari Sayadi, M. Rostaei Alimehr, M. Haghighian Roudsari,
Volume 8, Issue 4 (1-2005)
Abstract
Two hundred Arian broiler chicks were used to investigate the effect of contents of dietary glucosinolates on performance of broiler chicks during starter (0-21 days of age) and grower periods (22-42 days of age) in a completely randomized design. The dietary glucosinolates contents in the starter period were 0 (S1), 7.5 (S2), 15 (S3), 22.5 (S4), 30 (S5) µmol/g and in the grower period they were 0 (G1), 5.7 (G2), 11.4 (G3), 17.1 (G4), 22.8 (G5) µmol/g. Feed intake during the grower period was affected (P<0.05) by different levels of glucosinolates in the diets and the lowest feed intake was observed in the G5 treatment. The lowest body weight gains were observed in the S5 and G5 treatments during the starter and grower periods, respectively (P<0.05). The feed conversion ratio (FCR) in the S5 treatment for the starter and the G5 treatment for the grower period were significantly different (P<0.05) from other treatments. The correlation between the body weight gain and level of dietary glucosinolates or glucosinolate consumption was high during the starter (r = -95.3% and -94.7%, respectively) and relatively high (r = -69.5% and -72.4%, respectively) during the grower period. This experiment showed that the amount of glucosinolates in the diets of broiler chicks for the periods of starter and grower feeding system should not be more than 11.36 and 8.11µmol/g diet, respectively. Also during the starter and grower feeding periods, the highest level of rapeseed meal could be used in the broiler diets are 13 and 8 percent, respectively.
F. Khajali,
Volume 9, Issue 3 (10-2005)
Abstract
This study was carried out to evaluate the duration of time of feeding starter and finisher diets on live performance and carcass characteristics of female broilers. Starter diet was fed to 14 or 21 days of age. Finisher diet was fed beginning at 35 or 42 days up to 49 days of age. The results indicated that reduction of duration of feeding starter diet reduced weight gain (P<0.0071) and impaired feed conversion ratio (P<0.0002) up to 21d. Reduction of time of feeding starter diet caused a decrease in body weight at 21d (P<0.0071) whereas it had no effect on body weights at 42 and 49 days. Increasing time of feeding finisher diet caused a drop of the weight gain (P<0.0076) and impaired feed conversion ratio (P<0.0001) up to 42d but these differences were not significant up to 49d, suggesting a catch-up growth during 42 to 49d. There was no significant effect of dietary treatments on carcass characteristics at 49 days of age. Lowering time of feeding starter diet and increasing time of feeding finisher diet caused a significant decrease in pH, moisture and nitrogen contents of the litter.
M. J. Agah, J. Pourreza, A. Samie, H. R. Rahmani,
Volume 10, Issue 2 (7-2006)
Abstract
This experiment was carried out to determine the effects of different levels of (Kabuli) chickpea grains with different processing methods on the performance of broilers. In a factorial experiment with completely randomized design, 576 Rose broiler chicks were divided into 16 treatments with three replications of 12 chicks each. The first factor comprised three levels of chickpea (10, 20 and 30 percent) in ration, and the second factor five processing methods of chickpea (raw, cooked for 10 and 20 mins, and soaked for 24 and 48 hrs). Treatments included one control ration (without chickpea) and 15 experimental rations, all of which were isoenergetic and isonitrogenous. The experimental period lasted 8 weeks for the 1 to 56 day old chicks. Body weight gain, feed intake, feed conversion ratio were determined at three age periods of 7 to 21, 7 to 42 and 7 to 56 days. Carcass, abdominal fat, intestine and pancreas weight percentages to live weight were measured. Maximum body weight gain belonged to chickens fed on %30 chickpea grains soaked for 48h in age periods of 7 to 42 and 7 to 56 days, which was significantly different from control diet (P<0.05). The effect of chickpea grains levels and processing methods on chicken feed intake in age periods of 7 to 56 days was not significant. Interaction effects of chickpea levels with processing methods on feed conversion ratio in three age periods was not significant either. The effect of chickpea grains levels and processing methods on carcass, abdominal fat and intestine weight percentages to live weight were not significant except for the pancreas weight percentage (P<0.05). Therefore, it seems that chickpea grain is a suitable source of energy and protein in broiler diet (20% as raw or 30% as soaked for 48% h) when soyabean meals and corn grains are unavailable.
S.a.h. Abolghasemi, A.r. Jafari-Sayadi, S.m.a. Jalali-Hajiabadi, Z. Ansari-Pirsaraei,
Volume 10, Issue 4 (1-2007)
Abstract
To study the effects of terbutaline (a beta adrenergic agonist) on performance of broiler chickens, 21 d-old male and female Cobb broiler chicks (n=300) were randomly assigned to one of five dietary treatments containing 0 (control), 5, 10, 15 and 20 mg terbutaline per kg diet. The feed conversion ratio (FCR), feed intake and body weight gain were measuered after 3 weeks. At 42-d age, six males and six females were randomly selected from each treatment and their live weight and weights of carcass, breast, breast muscle, drumsticks, drumstick muscle and abdominal fat were determined. Terbutaline didn’t affect daily weight gain, but FCR of male chicks was reduced for 5 and 10 mg/kg terbutaline treatments comapared with the control group (p<0.05). Carcass weight and weight of drumsticks, drumstick muscle, breast, breast muscle and ratio of breast to live weight of female chicks reciving 5 mg/kg terbutaline were higher than for other treatments (p<0.05). In male chicks, the live weight and weight of carcass, ratio of carcass to live weight, drumsticks and drumstick muscle at 5 mg/kg terbutaline treatment were higher than for other treatments (p<0.05). This experiment also showed that the addition of 5 mg terbotaline per kg diet during growing period improved FCR and ratio of carcass to live weight of male chicks, increased the ratio of breast to live weight of female chicks, and increased the carcass weight of male and female Cobb chicks.
M. Heidari Soltanabadi, A. Hemmat,
Volume 11, Issue 1 (4-2007)
Abstract
Studies show that excessive rotation of rice, when the grains revolve inside the milling chamber, increase the breakage. Ease of grain movement in the milling chamber could minimize this problem by utilizing screw conveyor at the first part of rotor. In this study the rotor of a conventional milling was equipped with a screw conveyor. The effects of two rotor types (modified and conventional rotors), three output rates (412, 654 and 915 kg/h) and three blade distances from the agitator (11, 12 and 13mm) were examined on indices of rice quality using a split-split plot design. In this experiment, the percentage of whole white rice and breakage, degree of milling and milling performance index were either measured or calculated. Results showed that only the effect of blade distance on percentage of breakage was significant whereas the effect of feed rate on all measured parameters was significant. In addition, the interaction effects of rotor type and blade distance, rotor type and feed rate on percentage of whole white rice and breakage were significant, respectively. The milling performance index showed that the best conditions for both rotors can be obtained at output rate of 412kg/hr and 11or 12mm blade distance from the agitator. For this adjustment, the average of percentage of breakage in the modified and conventional rotors were 20.5 and 23, respectively.
H. Kermanshahi, M. R. Akbari, N. Afzali,
Volume 11, Issue 1 (4-2007)
Abstract
A feeding trail was conducted to evaluate the effects of diets contaminated with Aflatoxin B1 (AFB1) on the performance and blood enzymes of broiler chickens. In a randomized complete-block design with 4 blocks and 4 treatments, 112 day-old male broiler chicks were divided into 16 groups, 7 chicks per. Treatments consisted of three levels of AFB1 in starter diet (0.4, 0.8, and 1.2 ppm) along with a control group (no AFB1). Feed intake and body weight gain were recorded on a weekly basis. On days 7, 14, 21, and 28, one bird from each replicate was weighed, and killed to collect the blood samples, and to weigh its proventriculus, gizzard, duodenum and pancreas, heart, liver, spleen, bursa of fabricius, and brain. Feeding AFB1 significantly decreased feed intake and body weight gain and increased relative weight of liver (p<0.05). Relative weight of brain decreased on day 7 and then showed a significant increase by day 28 (p<0.05). AFB1 significantly (P<0.05) increased serum activity of aspartate amino transferase (AST) and alanine amino transferase (ALT) and decreased serum activity of lactate dehydrogenase (LDH) enzymes. Generally, this study demonstrated that, alongside other negative effects, AFB1 could also have adverse effect on the brain of broilers.
R. Hashemi, B. Dastar, S. Hassani, Y. Jafari Ahangari,
Volume 11, Issue 1 (4-2007)
Abstract
The effect of dietary protein level and feed restriction on performance, body temperature and hematological values was evaluated, using Ross 308 broiler chicks under heat stress. For this purpose, three dietary treatments were fed to broilers during 21 to 42 days of age. Two treatments consisted of diets with protein levels recommended by NRC, 1994 and 85% of NRC recommendation and were fed ad-lib during the experiment. The third treatment was a feed restriction group that was fed diet with protein level recommended by NRC, but chicks were deprived of feed for 6 hours during heat stress challenge. Birds had free access to water. Results indicated that lowering protein content or feed restriction had no significant effect on body weight gain (P>0.05). Feed restriction resulted in significantly decreased feed intake, improved feed conversion and energy efficiency ratio, and decreased body temperature after heat stress challenge at 24 and 32 days (P<0.05). Lowering protein of diet and feed restriction resulted in significantly decreased protein intake, improved protein efficiency ratio and increased hematocrit and blood uric acid (P<0.05). Sex had no significant effect on body temperature and hematological values (P>0.05). Heat stress significantly increased body temperature, hematocrit and glucose and uric acid values.
S.a. Mohseni Movahed, M.j. Monem,
Volume 11, Issue 40 (7-2007)
Abstract
Poor performance of irrigation canals and its effect on decreasing of Agricultural water productivity require attention for their improvement. In this paper a new mathematical model is introduced which could present optimal operation considering downstream requirements of turnouts, canal inlet flow, actual constraints and real conditions of canal system. Four performance indicators of delivery including efficiency, adequacy, equity and stability are considered as an objective function in the process of optimization. Since this objective function is an implicit function of decision variables (regulation of turnouts and control structures) and hydraulic parameters, it is necessary to implement hydrodynamic model, using numerical optimization methods. SA (Simulated Annealing) technique is a numerical
meta – heuristic intelligent search method which is used in combination with a hydrodynamic model (ICSS) (Irrigation Conveyance System Simulation.) for performance optimization of canal system. Theoretically it is proven that SA technique is capable of tending towards global optimum solution asymtotically. Taking short random steps in SA algorithm guarantees avoiding instability in hydrodynamic model. The developed model has been applied on E1R1 Distributary canal of Dez irrigation network for ten days. The results indicated that optimal performance improved very well in comparison with the present situation.In this model the weighting coefficients of indicators are determined using sensitivity analysis in optimization process. Consistency test on the derived coefficients shows that proposed method is appropriate. Applying weighting coefficients for performance indicators in the processes of optimization has resulted in 7 to 21 percent improvement compared to the case of equall weighting coefficients. Also, the results indicate that the developed model (ICSS-DOM) (ICSS-Delivery Optimization Model) is an efficient tool for the evaluation and optimization of irrigation canal performance, producing good and valid results in a relatively short and suitable time.
M.d. Shakouri, H. Kermanshahi,
Volume 11, Issue 40 (7-2007)
Abstract
In order to study the effect of corn, Ghods wheat, Falaat wheat, and triticale with or without enzyme addition on perormance and digestive tract characteristics, an experiment was carried out by using 288 male broiler chickens in a compeletly randomized design with 4*2 factorial arrangement for 57 days. Enzyme addition significantly decreased both feed conversion ratio of chickens fed Ghods wheat and triticale, and weight gain of chickens fed Ghods wheat. Growth performance of chickens fed Ghods wheat with enzyme was not significantly different compared with corn without enzyme. Enzyme addition decreased ileum relative weight of chickens. Gizzard and proventriculus of chickens fed Falaat wheat and triticale were heavier than those of other treatments. According to the results, enzyme supplementation showed positive effect on triticale and especially Ghods wheat based diets.
F. Shariatmadari, A. A. Moghadamian,
Volume 11, Issue 40 (7-2007)
Abstract
The purpose of this research was to evaluate the effect of early life nutrient restriction and subsequent intermittent lighting schedule on performance in broiler. In a factorial experiment, the effect of three levels of feeding regimes and two levels of lighting schedule were investigated using 480 day-old male Hubbard chicks. The broiler chickens were randomly distributed over two rooms consisting of 4 replicates of 20 birds for each of three treatment groups. From 3 to 12 days of age treatment groups were either allowed ad-libitum access, 90% or 80% to feed. From 12 days of age until 42 days of age all birds were allowed ad-libitum access to feed. The lighting schedule for day 12 onwards in one room was a 23h light (L): 1h dark (D) lighting schedule (CL) and another room with an intermittent lighting schedule (IL, 1L:3D) from 8 AM until 8 PM . The results indicated that feed intake and feed conversion ratio of birds reared in the IL schedule were significantly lower than CL , at growth and total period of experiment (p<0.01). IL schedule did not have any significant effect on mean body weight at the end of experimental period and body weight gain at total period of experiment(p>0.05). Relative growth rate and production (PI( in the IL were higher than CL schedule (p<0.01). Feed intake and feed conversion ratio of birds given 90 and 80% of ad libitum were significantly lower in comparison with control group (p<0.01). Body weight (gain) at the end of the experiment and growth period and body weight gain in birds fed 80% of ad libitum group were significantly lower in comparison with control and 90% of ad libitum groups. At 5,6 weeks and grower period EPI and relative growth rate in birds fed 80 and 90% of ad libitum were significantly higher in comparison with control. These results indicated that feed restriction and lighting program did not have any significant effect on carcass composition (protein, fat, ash and dry matter), carcass fragment percentage (except for drumstick), abdominal fat percentage, lung , heart, right and left ventricle weight and hematocrit percentage (p>0.05), but proportion of heart weight to body weight and drumstick percentage in birds fed 80 % of ad libitum were higher than the other groups (p<0.05). Lighting schedule and feeding regime did not have any interaction effect, except for relative growth rate (p<0.05). Relative growth rate in birds with feed restriction under IL schedule was higher than birds with feed restriction under CL schedule. Intermittent lighting and feed restriction had synergic, activity effect and positive effect on body weight gain and feed convertion ratio.
H.r. Rahmani, A.a. Gheisari, R. Taheri, A. Khodami, M. Toghiani,
Volume 12, Issue 43 (4-2008)
Abstract
This experiment was conducted to evaluate the effects of 7 experimental diets (2 diets containing 100 and 200 mg vitamin E (VE)/kg and 5 diets containing 0, 0.5, 1, 1.5 and 2% green tea powder (GTP) ) on performance and breast and thigh meat oxidative stability of broiler chicks during different storage times. A total of 364 male broiler chicks were divided to 28 groups of 13 chicks each. Then every 4 groups were randomly allocated to one of experimental diets. During the experimental period (7-42 days of age) feed intake, weight gain and feed conversion of the experimental groups were measured. On day 42, 2 birds from each replicate (8 chicks per treatment) were weighed, slaughtered and their muscles of breast and thigh were minced and stored at 4ºC. Meat oxidative stability of the samples was determined on days 0, 6 and 9 of storage time using thiobarbituric acid test (TBA test). The results showed that addition of the VE and GTP to diets tended to significantly (P<0.05) reduce live body weight, weight gain, feed intake and abdominal fat accumulation and increase feed conversion ratio and pancreas size compared to control group. Increasing storage time from 0 to 6 and 9 d significantly (P< 0.05) increased TBA number. Lipid peroxidation and TBA values in thigh muscle were significantly (P<0.05) higher than breast muscle (1.46 vs. 0.359 mg Malonaldehyde/kg meat). Different dietary levels of GTP in diets did not have any significant effect on prevention of meat lipid peroxidation. In addition, the values of TBA in meat of the groups fed diets containing high levels of GTP significantly (P<0.05) increased in comparison to control group and those fed VE supplemented diets.
H. Amanlou, D. Zahmatkesh, A. Nikkhah,
Volume 12, Issue 43 (4-2008)
Abstract
24 Holstein cows and 16 Holstein heifers in close-up period were used to evaluate the effects of ground wheat grain in prepartum diets on health and performance of dairy cows. Cows were blocked based on parity (three groups) and then randomly assigned to two experimental diets. Study rations included a treatment containing wheat with 1.62Mcal/kg NEL, 14.8%CP, 42.1%NFC, and –64meq/Kg DCAD and another treatment was composed of barley and wheat bran with 1.59Mcal/kg NEL, 14.8%CP, 38.2%NFC, and –48meq/Kg DCAD. Cows were fed experimental diets in group, on average 24%4 days prior to parturition, and they were fed the same ration up to day 21 postpartum. Average feed intake prior to confining, milk yield and composition, blood metabolites, feeding and chewing activity, urine and feces pH, placenta weight and time of its omitted, pregnancy duration, parturition status, body weight and BCS, and metabolic disorders were evaluated in this research. Average feed intake for wheat treatment was more than barley and wheat bran treatment (11.56 in contrast to 10.74, Kg DM), but it was not statistically significant. Milk production in wheat treatment had no significant increase. Milk fat yield in wheat treatment had a higher value compared to barley and wheat bran treatment (P<0.025). Blood calcium in wheat treatment was significantly higher (P<0.005), and blood glucose in wheat treatment was significantly higher than barley and wheat bran treatment (P<0.011). Changes in body weight and BCS, pregnancy duration and parturition status were not significantly different between treatments. Urine pH in wheat treatment had a significant decrease in the last week prior to parturition (P< 0.003).
M.r. Barekatain, J. Pourreza, A.h. Samie, S.a. Tabeidian, E. Rowghani,
Volume 12, Issue 43 (4-2008)
Abstract
This experiment was conducted to determinate the effects of different levels of Amet protein binder (0, 1.5, 3, 4.5 and 6) in substitution for fish meal on performance and digestibility of nutrients. This study used 400 broiler chickens (Ross strain) with 5 treatments of 4 replications in a completely randomized design. Weight gain, feed consumption, and feed conversion ratio were determined at the end of each phase of the experiment. In addition, the digestibility of nutrients and apparent metabolizable energy (AMEn) of the whole diets were measured by sampling excreta. The results showed that levels of 4.5 and 6% of Amet significantly decreased feed consumption (P< 0.01). Feed consumption was higher for 1.5, 0(control), and 3% Amet in diets, respectively. At the starting phase, 1.5% Amet treatment improved feed conversion ratio (P<0.01). The treatments 6% and 4.5% Amet increased feed conversion ratio in all phases of experiment and the final phase. Percentages of abdominal fat were not significantly affected by treatments. Replacement of different levels of Amet except the treatment 6% had no significant effect on percentage of carcass. The level of 1.5% Amet versus control significantly increased AMEn (P<0.01). It seems that the inclusion of 1.5% Amet binder in the diet can positively affect performance and AMEn of diet in broiler chickens.
A. Mahmoodi Pour, M. Esna-Ashari, O. Karami, M. Hesari,
Volume 12, Issue 45 (10-2008)
Abstract
Resveratrol (5,3,4'- trihyroxystilbene) is a valuable polyphenolic compound which prevents cancer, heart and vascular diseases in human. In this research, the compound was extracted from leaf and fruit tissues of two Iranian grape cultivars (Rajabie Sefide Shiraz and Keshmeshie Ghermez) using a general extraction method with some modification, and analyzed quantitatively by High Performance Liquid Chromatography (HPLC). Resveratrol content in leaf and fruit of Rajabie Sefide Shiraz cultivar was higher than Keshmeshie Ghermez and its amount in the fruits of both cultivars was observed to be greater than their leaves. The accumulation of Resveratrol at the early stage of fruit growth (4 weeks after full bloom) was higher than the subsequent stages of fruit growth and development (8 weeks after full bloom and ripened fruit) in both cultivars. This compound gradually decreased from the beginning of fruit set to the complete stage of growth and development and reached the lowest level when the fruits were ripe. Leaves and fruits of both cultivars were treated with methyl jasmonate (1 mM), then the rate of resveratrol was measured after treatments. It was observed that the amount of this compound was significantly increased in treated samples when compared with the control however, the difference diminished later. The fruits of both cultivars responded better to the treatments 4 weeks after full bloom.
Sh. Zamani, A. Parvaresh Rizi, S. Isapour,
Volume 17, Issue 66 (2-2014)
Abstract
Modernization of irrigation canals as an operation improvement tool is essential to promote the performance of canal networks and indeed requires control systems. Proportional integral derivative (PID) algorithms have more applications than the other controllers in different places of the world, but tuning these controllers for different hydraulic conditions of canals is considered as a major problem for designing control algorithms. Since the bottom slope is one of the effective factors in the water flow dynamic behavior, in this research, the distant downstream Proportional Integral Derivative feedback control with decouplers was designed with a change in longitudinal slope in a reference canal and its performance was investigated. The canal characteristics were used to tune this controller and the system identification as a new method was applied for determining canal characteristics. SOBEK hydrodynamic model modulated with MATLAB software was used to design and run the control algorithms, and slope influence on water flow behavior, tuning controller, and coefficients of controller were investigated with different values of slope. Then, controller performance for hypothetical period of operation in various scenarios was evaluated with computation performance indices. The results showed less resonance behavior of water flow and less potential of controller in steep slope
B. Moumeni, M. Masoudian, M. A. Gholami Sefidkohi, A. Emadi,
Volume 22, Issue 3 (11-2018)
Abstract
Over the years, since the beginning of the national and infrastructural project of Development and Renovation of Paddy Fields of Iranian Northern provinces, it has been essential to evaluate water distribution and delivery Performance of the project to get its feedback in the pursuit of the desired goals. However, the results of the evaluation of a system can reliable when they are based on quantitative indicators, not on personal opinions and empirical judgment. So, in this study, Total Error (TE) of performance of water delivery system, a statistical indicator, and its component including adequacy, water management capability and equity errors were calculated and compared for two concrete and earthen irrigation canals. This analysis was done based on calculating water demand and measuring the volume of delivered water between outlets during the irrigation season in the paddy fields of Esmaelkola of Joybar city, in 2015. According to the results, although the concrete channel (0.28) had less error than the earthen channel (0.43) and in the concrete channel, as compared to the earthen channel, the share of the components of adequacy and water management capability from the total error was dropped from 47% to less than 10%, but the error in the water delivery of the concrete channel was still high due to the error in the equity of distribution, whose value was 0.25 (90% of the total error). Therefore, in order to reduce the performance error, after channel lining, it would be necessary to make fundamental changes in the intake and flow control structure in addition to the training of irrigators regarding water delivery based on water demand.
D. Salehi, M. Goodarzi, H. Montaseri,
Volume 23, Issue 4 (12-2019)
Abstract
This research tried to provide a sustainable solution for the allocation of water resources of Zayandehrood basin in a way ensuring minimal conflicts and tension between the stakeholders in use of the water resources, four main decision makers of the basis, comprising Regional Water Company, conflicts among Agricultural Jahad Organization, and Department of Environment of Isfahan Province and Chaharmahal and Bakhtiari Province, were reviewed and 128 possible cased according to 7 scenarios were constructed and applied in the GMCR model. According to the GMCR approach, 6 balanced sustainable scenarios in different climatic periods of the basin were presented. Finally, the results were generalized for choosing the best mode in the form of a scenario within the WEAP model; also, the results obtained from these scenarios were presented using the criteria of system performance assessment. On the basis of the findings, Scenario II was developed, comprising the application of new simultaneous management of demand and supply, restrictions in drawing water from water tables, new prioritization in stakeholder allocation and new water portion plans in the basin as the best scenario with 81.4% sustainability index.
M. Fuladipanah, M. Majediasl,
Volume 24, Issue 4 (11-2020)
Abstract
The prediction of local scouring as a dynamic and nonlinear phenomenon using methods of acceptable predictive capability has always been of interest to researchers. The shape of the bridge pier is one of the important factors in the formation and magnitude of the scour hole. In this paper, the scour depth of three bridge piers with cylindrical, sharp nose and rectangular shapes was predicted in two scenarios using the support vector machine algorithm with 395 field data obtained from the US Geological Survey and Froehlich (1988), based on different combinations of dimensionless parameters as the water attack angle (α), Froud number (Fr), the ration of pier length to width (l/b), and the ratio of mean sediment size to pier width (D50/b). The results of the study, while confirming the acceptable performance of the SVM algorithm for all piers in both scenarios, showed that in the first and second scenarios, the most optimal performance was related to the rectangular pier shape with correlation coefficient of 0.8702 and 0.8838, with and maximum Ds (DDR) values of 0.854 and 1.229 respectively, during the testing phase. The positive effect of increasing the number of data on the performance of the SVM algorithm was also confirmed by further probing the evaluation indicators. The results of the comparison pointed out the overestimation of the predicted scour depth values of absolute error between 11% to 35%.
F. Ahmadzadeh Kaleibar, M. Fuladipanah,
Volume 27, Issue 2 (9-2023)
Abstract
Using transfer functions to predict soil moisture parameters has been considered strictly a scientific and economical method among researchers. In this research, field capacity (FC) and permanent wilting point (PWP) of soil were predicted using classic regression (linear and non-linear), support vector machine (SVM) algorithm, and gene programming expression (GEP) algorithm based on three performance assessment criteria as determination of coefficient (R2), root mean square error (RMSE), and standardized developed discrepancy Ratio (DDR) in the Arasbaran plain in the northwest of Iran. Independent parameters were determined as clay percent (Cl), silt percent (Si), gravel percent (Sa), organic carbon (OC), bulk density (ρb), and actual density (ρs) which (S, ρb, ρs) and (ρb, ρs) were opted to predict FC and PWP using Gamma test, respectively. The results showed that each three transfer functions are capable to simulate FC and PWP parameters but the SVM algorithm is the superior predictor among the three functions so the values of (R2, RMSE, and DDRmax) of training and testing phases for FC were obtained (0.9908, 0.5517, 17.50), (0.9785, 0.7004, 11.62) and those of PWP were calculated (0.9782, 0.5764, 2.85) and (0.8389, 1.187, 3.09), respectively.