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۱A[VG1][VG2][H3] GLANCE AT HISTORICAL QANATS IN IRAN WITH AN EMPHASIS ON VAZVAN QANAT IN ISFAHAN
نویسنده(ها):
اطلاعات انتشار: سمینار بین المللی تاریخ آبیاری و زهکشی، سال
تعداد صفحات: ۸
Qanat is a way of conveyance of underground water to ground surface for irrigation and drinking. This is a technology born and developed in Iran and extended to other countries in the East and the West over the time. The total number of Iranian Qanats is 18000 and their total discharge is about 7.4 billions cubic meters. Among the Iranian Qanats some of them are specific from the point of view of mother well depth, length, rate of flow, oldness and attractiveness. Keikhosrow Qanat in Gonabad (Khorasan Province) has the deepest mother well, that is 400 meters. One of the Yazd Qanats has the largest tunnel that is 116 kilometers. The most flow rate Qanat is Payekam Qanat in Bam suburb which is 312 lit\s. From innovation and talent point of view, there are few historical Qanats in Isfahan such as Moon Qanat in Ardestan in which the tunnel has
two parallel floors and Vazvan Qanat in which flowing water is collected beyond an underground dam for a period for irrigation purposes over the following year. There are a large number of benefits resulted from Qnanats, and few disadvantages as well, but the benefits are more. If the idle Qanats are repaired and renewed, then the rate of available water will be 1.7 billions lit\s, i.e. 4 times of Karroon River in Iran or ¾ of Nile River in Egypt. But from author’s point of view, this is not possible, because of shortage of rainfall and falling water level tables which had been happened due to huge number of dug wells.<\div>

۲Simultaneous Application of EKF and RLS Methods for Induction Motor Speed and Parameters Estimation
نویسنده(ها): ، ، ،
اطلاعات انتشار: بیست و یکمین کنفرانس بین المللی برق، سال
تعداد صفحات: ۸
In this paper the induction motor’s parameters and speed are estimated by the application of two methods. The Extended Kalman Filter (EKF) and Recursive Least Square (RLS) are used to implement the estimator. Combination of these algorithms has been investigated and the results are presented. The possibility of the application of these methods for on–line motor speed and parameter estimation for using in drive application has been analyzed. The theoretical development of algorithm is followed by simulation study which is used to illustrate the possible range of behavior including the introduction of noise and modeling errors.<\div>

۳PREDICTING WATER LOSSES (RUNOFF) UNDER MOVING SPRINKLER IRRIGATION USING THE EUROPEAN SOIL EROSION MODEL (EUROSEM)
نویسنده(ها):
اطلاعات انتشار: اولین کنفرانس بین المللی بحران آب، سال
تعداد صفحات: ۱۱
Moving sprinkler irrigation systems such as centre pivots and rain guns can have excessively high water application rates and are prone to water losses due to runoff problems. This is exacerbated by the trend to low pressure operation, for the reason of saving energy, which adds to the problem.
Runoff problems are traditionally dealt with in the field either by adjusting the irrigation system or the cultivation practices. This paper describes a more fundamentally based approach to predict runoff from moving sprinkler irrigation. A well known runoff–erosion model called EUROSEM is used to predict runoff from both plane and ridge and furrow cultivation and is validated by field experiments.
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۴A Modified DTC for Induction Motor Drive System Fed by Indirect Matrix Converter Using Active Learning Method
نویسنده(ها): ، ، ،
اطلاعات انتشار: دومین کنفرانس بین المللی الکترونیک قدرت و سیستم های درایو، سال
تعداد صفحات: ۶
This paper presents a high performance Direct Torque Control (DTC) theme for the induction motor using Indirect Matrix Converter (IMC). To improve the dynamic behavior of motor, Active Learning Method (ALM) is implemented on the DTC. The ALM uses its own modeling technique called the ink drop spread (IDS) method. Functionally the IMC is very similar to the Direct Matrix Converter (DMC) but it has separate line and load bridges. In the inverter stage, the classical DTC method is employed. In the rectifier stage, in order to reduce losses caused by snubber circuit the rectifier four–step commutation method is employed. By suitably selecting switching pattern and using Active Learning Method the electromagnetic torque ripple of the motor is effectively reduced. The simulation results of proposed strategy and confirm its effectiveness and accuracy.<\div>

۵Eight new records of bird species from North–Eastern Iran
نویسنده(ها): ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: Iranian journal of animal biosystematics، هفتم،شماره۱، ۲۰۱۱، سال
تعداد صفحات: ۱۹
During ornithological expedition to four provinces in the northeast and north of Iran in June 2009, a total of 117 bird species belonging to 14 orders and 40 families were recorded. Based on these records, eight bird species were found outside their presumed breeding range according to the available distribution maps covering Iran, suggesting that updating of the distribution maps should be provided.

۶Length–weight and length–length relationships, Relative condition factor and Fulton?s condition factor of Five Cyprinid species in Anzali wetland
نویسنده(ها): ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: Caspian Journal of Environmental Sciences، دهم،شماره۱، ۲۰۱۲، سال
تعداد صفحات: ۸
This study was conducted to determine length–weight and length–length relationships, relative condition factor (Krel) and Fulton?s condition factor (K) for five species including Scardinius erythrophtalmus, Carassius auratus gibelio, Cyprinus carpio, Tinca tinca and Hemiculter leucisculus belonging to Cyprinidae family. Fish sampling was carried out by gill net and fyke net in the western region of Anzali wetland (SW of the Caspian Sea) between Nov. 2010 and May 2011. 368 specimens were measured and weighed. The values of the exponent b in the length–weight relationships (LWRs) ranged from 2.5358 to 3.3613 and those of the length–length relationship (LLRs) ranged from 0.8717 to 0.9412. Also, relative condition factor (Krel) ranged from 1.00?0.11 to 1.30?0.21 and Fulton?s condition factor (K) ranged from 0.80?0.05 to 1.60?0.18 for all species.
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