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Pedosphere 2011年第2期21卷 230-237页

作者： Y.ABBa.i B.GHANBa.iAN-ALa.iJEH A.M.liaghat M.SHORAFA Department of irriga.ion and Reclama.ion Engineering University of TehranKaraj 31587-77871 (Iran) Department of Earth and Environmental Sciences Wright State UniversityDayton OH 45435 (USA) Department of Soil Science Engineering University of TehranKaraj 31587-77871 (Iran)

Soil water retention data are essential for irriga.ion scheduling and determina.ion of irriga.ion frequency. However, direct measurement of this characteristic is time consuming and expensive and furthermore its spa.ial and temporal va.ia.ilities in field scales increase the number of measurements. Different pedotransfer functions, such as Saxton et al., Campbell, Vereecken et al., l^awls and Brakensiek, WSsten et al., Rajkni et al., Ghorba.i Dashta.i and Homaee, Zacha.ias and Wessolek, and Rosetta, were evaluated to estimate soil water retention of sa.ine and sa.ine-alka.i soils collected from south of Tehran, iran. The satura.ion-extract conductivity of all the 68 samples and exchangeable sodium percentage of more than half of them were measured to be greater than 4 dS m-1 and 15%, respectively. The calculated Akaike＇s informa.ion criterion values showed that Saxton et al. and Campbell models were the best in estima.ion of soil water retention curve and total available water, respectively.

关键词： exchangeable sodium percentage irriga.ion frequency soil moisture curve total available water

EXPERiMENTAL AND THEORETiCAL iNVESTiGa.iON OF THE FiRST FOLD CREa.iON iN THiN WALLED COLUMNS

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Acta Mecha.ica Solida Sinica 2010年第4期23卷 353-360页

作者： Abbas Niknejad G.H.liaghat H.Moslemi Na.ini A.H.Behravesh Mecha.ical Engineering Department Yasouj University Faculty of Engineering Payame Noor University (PNU) Mecha.ical Engineering Department Faculty of EngineeringTarbiat Modares University

in this paper, a theoretical formula.is presented to predict the instantaneous folding force of the first fold crea.ion in square and rectangular columns under a.ial *** rectangular column is a small and single model of honeycombs with square or rectangular *** are based on the analysis of the Ba.ic Folding Mecha.ism （BFM）.For this purpose, sum of the dissipated energy rate under bending around horizontal and inclined hinge lines and the dissipated energy rate under extensional deforma.ions was equal to the work rate of the external force on the *** final formula obtained in this research, reasonably predicts the instantaneous folding force of single-cell square and rectangular honeycombs instead of the average ***, according to the calculated theoretical rela.ion, the instantaneous folding force of the first fold crea.ion in a square column was sketched versus folding distance and compared to the experimental results, which showed a good correla.ion.

关键词： dissipated energy rate first fold crea.ion instantaneous folding force thin walled column

intrathecal hematoma and sacral ra.iculitis following repeat epidural blood patch

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The Journal of Biomedical Research 2021年第1期35卷 68-71页

作者： Jeremy Wolfson John liaghat Hong Liu Cristina Chandler Department of Anesthesiology and Pain Medicine University of California Davis HealthSacramentoCA 95817USA.

Postdural puncture headache(PDPH)is an incapa.ita.ing complica.ion that can occur following spinal anesthesia and with inadvertent dural puncture during epidural *** present a case of a 32-year-old G2 P1 female who was admitted for induction of labor and received epidural catheter placement for *** an inadvertent dural puncture and development of a PDPH,the pa.ient was offered conserva.ive measures for the first 48 hours without *** epidural blood patch(EBP)was placed achieving only moderate *** days later,a second EBP was performed and the pa.ient developed severe back pain which ra.iated bilaterally to her *** resonance ima.ing(MRi)demonstrated the presence of blood in the intrathecal *** could be the cause of sacral ra.iculitis,an uncommon complica.ion of an *** suggests that EBPs could potentially cause neurologic symptoms which may be more common than people previously *** complicated outcomes have followed both conserva.ive and aggressive management,MRi can be an early diagnostic tool in such cases and a multidisciplinary approach should be taken.

关键词： postdural puncture headache epidural blood patch intrathecal hematoma sacral ra.iculitis

Estima.ion of the van Genuchten Soil Water Retention Properties from Soil Textural Data

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Pedosphere 2010年第4期20卷 456-465页

作者： B. GHANBa.iAN-ALa.iJEH A. liaghat HUANG Guan-Hua M. Th. VAN GENUCHTEN Department of irriga.ion and Reclama.ion Engineering University of Tehran Karaj 31587-77871 （Iran） Department of Earth and Environmental Sciences Wright State University Dayton OH 45435 （USA） Department of irriga.ion and Drainage Engineering China Agricultural University Beijing 100083 （China） Department of Mecha.ical Engineering Federal University of Rio de Janeiro RJ 21945-970 （Brazil）

The van Genuchten (vG) function is often used to describe the soil water retention curve (SWRC) of unsaturated soils and fractured rock. The objective of this study was to develop a method to determine the vG model parameter m from the fractal dimension. We compared two approaches previously proposed by van Genuchten and Lenhard et al. for estima.ing m from the pore size distribution index of the Brooks and Corey (BC) model. in both approaches we used a rela.ionship between the pore size distribution index of the BC model and the fractal dimension of the SWRC. A dataset containing 75 samples from the UNSODA unsaturated soil hydraulic database was used to evaluate the two approaches. The sta.istical parameters showed that the approach by Lenhard et al. provided better estimates of the parameter m. Another dataset containing 72 samples from the literature was used to va.idate Lenhard's approach in which the SWRC fractal dimension was estimated from the clay content. The estimated SWRC of the second dataset was compared with those obtained with the Rosetta model using sand, silt, and clay contents. Root mean square error values of the proposed fractal approach and Rosetta were 0.081 and 0.136, respectively, indica.ing that the proposed fractal approach performed better than the Rosetta model.

关键词： fractal dimension soil water retention curve van Genuchten parameteriza.ion

investiga.ion of Spa.ial and Temporal Distribution of Snow Cover by Using Satellite imagery (Case Study: Sheshpirdam Ba.in)

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Open Journal of Geology 2016年第5期6卷 330-340页

作者： a.i liaghat Nima Tavanpour Department of Water Engineering Shiraz Branch Islamic Azad University Shiraz Iran Department of Water Engineering Faculty of Agriculture Shiraz University Shiraz Iran

About one third of the water needed for agriculture in the world is generated by melting snow. Snow cover, surface and ground water recharge are considered as sustainable and renewable resources. it is therefore necessary to identify and study these criteria. The aim of this study is to determine the spa.ial and temporal distribution of snow cover in the district of the Sheshpir ba.in in Fars province (in south of iran). Ground-based observa.ion of snow covers, especially in mountainous areas, is associated with many problems due to the insufficient accuracy of optical observa.ion, as opposed to digital observa.ion. Therefore, GiS and remote sensing technology can be partially effective in solving this problem. images of Landsat 5TM and Landsat 7TM satellites were used to derive snow cover maps. The images in ENVi 4.8 software were classified by using the ma.imum likelihood algorithm. Other spa.ial analyses were performed in ARC-GiS 9.3 software. The ma.imum likelihood method was accuracy assessed by opera.ion points of testing. The least and the average of overall accuracy of produced maps were found to be 91% and 98%, respectively. This demonstrates that the ma.imum likelihood method has high performance in the classifica.ion of images. Overall snow cover and the review of terrain through the years 2008-2009 and 2009-2010 showed that snow cover begins to accumulate in November and reaches its highest magnitude in February. Finally, no trace of snow can be observed on the surface of the ba.in in the month of May. By average, 34% of the ba.in is covered in snow from November through to May.

关键词： RS GiS Ma.imum Likelihood Algorithm Snow Cover Spa.ial and Temporal Distribution

Predict Edges in Fliker Social Network Using Data Mining Method

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intelligent informa.ion Management 2012年第3期4卷 60-65页

作者： a.ir Hossein Rasekh Zeinab liaghat Ala Mahda.i Sha.if University of Technology Tehran Iran Young Researchers Club Sepidan Branch Islamic Azad University Sepidan Iran Young Researchers Club Shiraz Branch Islamic Azad University Shiraz Iran

Using social networking services is becoming more popular day by day. The websites of the social networks like face-book currently are among the most popular internet services just after giant portals such as Yahoo, MSN and search engines like Google. One of the main problems in analyzing these networks is the prediction of rela.ionships between people in the network. The purpose of this paper is to forecast the friendship of a person with a new person using existing data on Flickr website accurately. in this paper, we achieved about 90% percent correct prediction with regards to the results which are obtained by using data mining methods.

关键词： Social Network Data Mining Link Prediction Regression

USAGE MANAGEMENT OF WASTE WATER iN AGRiCULTURE

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USAGE MANAGEMENT OF WASTE WATER IN AGRICULTURE

Effect of Sa.ine Water on Cadmium Uptake and Remedia.ility of Soil with Brassica Napus

第19届国际灌排大会

作者： Abdolma.id liaghat a.ireza Hassanoghli Mehdi liaghat Associate professor of Tehran University Karaj Iran. Research Professor of Agricultural Engineering Research institute Karaj Iran Undergraduate student of isla.ic Azad University Karaj Iran

＜正＞There is a need for further irriga.ion development in a.id and semi-a.id countries where popula.ion is increa.ing and water scarcity is serious. Therefore, planners are forced to consider any or all source of water, including wastewater. However, use of wastewater in agricultural fields need some special type of management. The purpose of this study was to develop a novel method for applica.ion of wastewater to irrigate different crops without any ill effect. The study was undertaken in 12 large lysimeters, 85 cm height and 76×60 cm area. An industrial crop （Soya） was planted into four lysimeters and irrigated with primary treated wastewater containing 160 and230 mg/l of BOD5 and COD, respectively. A livestock feed crop （Corn） was planted into three lysimeters and irrigated with the effluents drained by soya-planted lysimeters （called soya-effluent）. A raw eaten vegetable crop （parsley） was planted into two lysimeters and irrigated with the effluents drained from corn-planted lysimeters （called corn-effluent）. in addition, each of the proposed crops were also, planted in a lysimeter and irrigated with well water as controls. Water samples were collected from drain effluents after each irriga.ion event and parameters such as;BOD5, COD, Total Orga.ic Matter and the number of coliform were measured. The results of this study show a significant reduction in all parameters in the soya and corn-effluent. The average BOD5 and COD levels were reduced to 9 and 36 mg/l in the soya-effluent and to 8 and 20 mg/l in the corn-effluent, respectively. More than 99% of the conforms were reduced from the raw wastewater after its passing through the soil and crop systems. No nematodes were found in the soya and corn-effluents. The result of this study was promising and indicated that the low qua.ity wastewater could be used for different crops using the proposed method.

关键词： Drainage effluent irriga.ion Lysimeter multi recycling wastewater.

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Journal of Chemistry and Chemical Engineering 2010年第12期4卷 1-6页

作者： Mohammad Mahdi Mohamma.i Abdolma.id liaghat Gholamreza Savaghebi Dep. of lrriga.ion and Drainage Eng. Faculty of Agricultural Engineering and Technology University of Tehran Karaj31587-11167 Iran Dep. of Soil Science Faculty of Agricultural Engineering and Technology University of Tehran Karaj 31587-11167 Iran

Phytoremedia.ion is a new technique for clea.ing conta.inated soils. This method in compa.ison with the other techniques is very simple and low cost. Among the pollutants, heavy metals and specially cadmium （Cd） is very important because of its high movement in soil and high toxicity. Bioavaila.ility of metals in the soil is affected by va.ious factors including sa.ine solution. in fact there are symptoms for increa.ing Cd uptake due to increa.ing C1＂1 concentra.ion in soil solution. The objective of this study was to investigate the effect of sa.ine irriga.ion water on cadmium uptake and remedia.ility of soil with Brassica napus （rapeseed） in greenhouse experiment. Sa.ine waters of 0, 1.5 and 2.5 dS/m was applied on soil with different concentra.ions of Cd （5, 10, 20, 30 and 50 ppm） during the cultiva.ion period of Oka.i （fall rapeseed va.iety）. The results of this study showed that there are no significant differences in shoot dry matter exposed to Cd, but root dry matter decreased with increa.ing Cd concentra.ion （p〈5%）. Sa.inity had a significant effect （p〈l%） on Cd concentra.ion in roots and increased from 26.83 （in control） to 36.46 ***-1 dry wt （in 2.5 dS.m＂l treatment）. The significant effect （p〈5%） was found in shoots as well and the Cd uptake was increased from 2.14 to 3.25 mg.m^-1dry wt in control and 2.5 dS＇m^-1 treatments respectively. Likewise, sa.inity increased bioaccumula.ion coefficient, whereas had no significant effect on transport factor. The obtained results showed that Cd metal tend to accumulate more in the roots ofBrassica napus than in the shoots.

关键词： Brassica napus cadmium heavy metals phytoremedia.ion sa.inity.

<i>Helicobacter pylori</i>microbe and detecting with data mining algorithms

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Open Journal of Gastroenterology 2013年第2期3卷 93-98页

作者： a.ir Hossein Rasekh Zeinab liaghat a.ireza Tabebordbar Computer Science and Engineering Department Shiraz University Shiraz Iran

Nowadays medicines believe that the only definite method to diagnose the existence of Helicobacter pylori microbe is performing endoscope, however it’s painful and insufferable for young children. Thus in this paper we used data mining algorithms to diagnose the existence of this microbe and eventually we succeeded in predicting the existence of this bacterium in stomach that guides medicines to perform Endoscopy just in cases where percentage of finding this bacterium is high.

关键词： Data Mining Helicobacter pylori Regression RBF Network Part

Artificial Neural Networks Applica.ion to Predict Wheat Yield Using Clima.ic Data

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Journal of Agricultural Science and Technology(B) 2011年第1期1卷 76-88页

作者： B. Safa A. Kha.ili M. Teshnehlab A. liaghat Department of Agronomy and Horticulture University of Nebraska-Lineoln 202 Keim Hall Lincoln NE 68583-0915 USA Department of irriga.ion and Reclama.ion Engineering College of Agriculture University of Tehran Karaj lran Department of Electrical Engineering K.N. Toosi Technology University Tehran lran

The goal of this study was to apply artificial neural networks to predict rain-fed wheat yield using meteorological data a few days to few months before harvesting. The clima.ic observa.ion data used; were mean of daily minimum and ma.imum temperature, extreme of daily minimum and ma.imum temperature, sum of daily rainfall, number of rainy days, sum of daily sun hours, mean of daily wind speed, extreme of daily wind speed, mean of daily rela.ive humidity, and sum of daily water requirements that were collected during 1990-1999 in Sararood Sta.ion for wheat phenological stages consisting; sowing, germina.ion, emergence, 3rd leaves, tillering, stem forma.ion, hea.ing, flowering, milk maturity, wax maturity, full maturity, separately for each growing season. Then, they arranged in a matrix whose rows form each of the sta.istical years and the columns are meteorological factors at each phenological stage. Finally, the obtained model had the following capa.ilities： Prediction of wheat yield with ma.imum errors of 45-60 kg/ha at least two months before full maturity stage, determina.ion of the sensitivity of each phenological stage with respect to meteorological factors, and determina.ion of the priority order and importance of each meteorological factor effective in plant growth and crop yield.

关键词： Artificial neural network wheat yield clima.ic data phenological stage crop model.