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Journal of Central South University 2016年第5期23卷 1163-1175页

作者： y.hashemi H.Shayeghi M.Moradzadeh A.Safari Technical Engineering Department University of Mohaghegh Ardabili Centre of Excellence for Power System Automation and Operation Department of Electrical EngineeringIran University of Science and Technology Centre for Engineering Innovation Department of Electrical and Computer EngineeringUniversity of Windsor Electrical Energy Laboratory Department of Electrical EnergySystems and AutomationGhent University Department of Electrical Engineering Azarbaijan Shahid Madani University

A mathematical approach was proposed to investigate the impact of high penetration of large-scale photovoltaic park(LPP) on small-signal stability of a power network and design of hybrid controller for these units.A systematic procedure was performed to obtain the complete model of a multi-machine power network including *** damping of oscillations focusing on inter-area oscillatory modes,a hybrid controller for LPP was *** performance of the suggested controller was tested using a 16-machine 5-area *** results indicate that the proposed hybrid controller for LPP provides sufficient damping to the low-frequency modes of power system for a wide range of operating *** method presented in this work effectively indentifies the impact of increased PV penetration and its controller on dynamic performance of multi-machine power network containing *** results demonstrate that the model presented can be used in designing of essential controllers for LPP.

关键词： hybrid controller multi-objective optimization large-scale photovoltaic park small-signal scrutiny

Comparison of biomechanical indices measured by ocular response analyzer between children and elderly:a systematic review

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 154-159页

作者： Hassan hashemi Fereshteh Shokrollahzadeh Hadi Ostadimoghaddam Abbasali yekta Mehdi Khabazkhoob Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Rehabilitation Research Center Department of OptometrySchool of Rehabilitation SciencesIran University of Medical SciencesTehran ***Iran Refractive Errors Research Center Mashhad University of Medical SciencesMashhad ***Iran Department of Optometry School of Paramedical SciencesMashhad University of Medical SciencesMashhad ***Iran Department of Medical Surgical Nursing School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

Biomechanical study of the visual system by ocular response analyzer investigates the inter-structural biological relationships,mechanics,and function of the visual *** review aimed to investigate the changes in corneal biomechanical parameters with age and *** articles published in PubMed between 2000 and 2021 were investigated and critiqued,and valid scientific evidence was collected,reviewed and concluded according to the inclusion and exclusion *** studies showed that corneal biomechanical changes occur infrequently in children up to the age of 20y,and with increasing age and wider age range,there was a significant decrease in corneal biomechanical indices,especially corneal *** children and adults,most studies have shown that these biomechanical indicators,especially corneal resistance factor,were higher in *** hormonal changes may contribute to this finding,the role of axial length and other biometric indicators should not be *** axial length,the intraocular pressure,and the corneal thickness are other factors associated with biomechanical parameters that should be taken into account in clinical diagnosis and management especially for patients undergoing refractive surgery as well as keratoconus patients.

关键词： ocular response analyzer corneal biomechanics visual function children elderly

Topographic factors associated with anterior chamber angle narrowing in patients with keratoconus

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 67-73页

作者： Hamed Soltan-Dehghan Abdollah Farzaneh Hassan hashemi Payam Nabovati Mehdi Khabazkhoob Rehabilitation Research Center Department of OptometrySchool of Rehabilitation SciencesIran University of Medical SciencesTehran ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Department of Medical Surgical Nursing School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this ***,complete ocular examinations were performed for all patients,including visual acuity measurement,refraction,and slit-lamp ***,all participants underwent corneal imaging by the Oculus Pentacam ***:The mean age of the participants was 32.40±8.52y(15-60y)and 69.5%of them were *** mean ACA was 38.47°±5.75°(range:14.40°to 56.50°)in the whole sample,38.24°±6.00°in males,and 38.98°±5.11°in females(P=0.447).The mean ACA was significantly different among different groups of cone morphology,as patients with nipple cones showed the lowest mean ***,there were statistically significant differences in the mean ACA among different groups of cone locations,with patients having central cones exhibiting the lowest mean ACA(Py,directly correlated with ACA(anterior Q:r=0.122,P=0.014,posterior Q:r=0.192,Py provides critical insights into the risk factors for ACA narrowing in KCN patients,which is essential for planning intraocular *** with nipple and central cones exhibited the most significant ACA ***,more negative Q-values are associated with increased ACA narrowing,highlighting the need for targeted diagnostic and therapeutic strategies.

关键词： keratoconus anterior chamber angle cone morphology cone location

Autorefraction versus subjective refraction in high astigmatism

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International Journal of Ophthalmology(English edition) 2025年第3期18卷 504-509页

作者： Haleh Kangari Hassan hashemi Saeed Rahmani Elnaz Ahmadian Abbasali yekta Mehdi Khabazkhoob Department of Optometry School of RehabilitationShahid Beheshti University of Medical SciencesTehran ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Noor Research Center for Ophthalmic Epidemiology Noor Eye HospitalTehran ***Iran Refractive Errors Research Center Mashhad University of Medical SciencesMashhad ***Iran Department of Medical Surgical Nursing School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM:To compare the subjective refraction data with autorefraction findings in high ***:In a cross-sectional study,sampling was done from in different geographic regions in Iran using a multistage random cluster sampling *** study participants underwent cycloplegic auto-refraction and subjective refraction using the red-green ***:In this study,277 eyes of 158 students aged 8 to 15y were *** to the results,the mean difference between subjective refraction and autorefraction in measuring sphere,cylinder,spherical equivalent,J0,and J45 was-0.18±0.76,-0.36±0.40,-0.36±0.79,0.15±0.20,and 0.05±0.21 *** correlation of these two refraction methods in measuring the aforementioned indices was 0.963,0.898,0.960,0.931,and 0.948 *** 95%limits of agreement of the two methods in measuring the above indices were-1.66 to 1.31,-1.14 to 0.42,-1.91 to 1.19,-0.24 to 0.54,and-0.36 to 0.47 *** agreement between the two methods decreased with increasing cylinder power,and the best agreement was found in myopic ***:The measurements obtained by autorefractometer have a significantly higher cylinder average compared to subjective ***,in the cylinder range of 4–5 diopters,the values of J0 and J45 do not have a high correlation.

关键词： subjective refraction autorefraction astigmatism

Attuned design of demand response program and M-FACTS for relieving congestion in a restructured market environment

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Frontiers in Energy 2015年第3期9卷 282-296页

作者： y. hashemi H. SHAyEGHI B. hashemi Technical Engineering Department University of Mohaghegh Ardabili Ardabil *** Iran Network Studies Group Bakhtar Regional Electric Company Arak *** Iran

This paper addresses the attuned use of multi- converter flexible alternative current transmission systems （M-FACTS） devices and demand response （DR） to perform congestion management （CM） in the deregulated environment. The strong control capability of the M- FACTS offers a great potential in solving many of the problems facing electric utilities. Besides, DR is a novel procedure that can be an effective tool for reduction of congestion. A market clearing procedure is conducted based on maximizing social welfare （SW） and congestion as network constraint is paid by using concurrently the DR and M-FACTS. A multi-objective problem （MOP） based on the sum of the payments received by the generators for changing their output, the total payment received by DR participants to reduce their load and M-FACTS cost is systematized. For the solution of this problem a nonlinear time-varying evolution （NTVE） based multi-objective particle swarm optimization （MOPSO） style is formed. Fuzzy decision-making （FDM） and technique for order preference by similarity to ideal solution （TOPSIS） approaches are employed for finding the best compromise solution from the set of Pareto-solutions obtained through multi-objective particle swarm optimization-nonlinear time-varying evolution （MOPSO-NTVE）. In a real power system, Azarbaijan regional power system of Iran, comparative analysis of the results obtained from the application of the DR ＆ unified power flow controller （UPFC） and the DR ＆ M-FACTS are presented.

关键词： multi-converter flexible alternative currenttransmission systems (M-FACTS) demand response,

An AlGaN/GaN HEMT with a reduced surface electric field and an improved breakdown voltage

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Chinese Physics B 2012年第8期21卷 360-364页

作者：谢刚 Edward Xu Niloufar hashemi 张波 Fred y.Fu Wai Tung Ng The Edward S.Rogers Sr.Electrical and Computer Engineering Department University of Toronto State key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Crosslight Software Inc.Burnaby BCCanada

A reduced surface electric field in an AlGaN/GaN high electron mobility transistor （HEMT） is investigated by employing a localized Mg-doped layer under the two-dimensional electron gas （2-DEG） channel as an electric field shaping layer. The electric field strength around the gate edge is effectively relieved and the surface electric field is distributed evenly as compared with those of HEMTs with conventional source-connected field plate and double field plate structures with the same device physical dimensions. Compared with the HEMTs with conventional sourceconnected field plates and double field plates, the HEMT with a Mg-doped layer also shows that the breakdown location shifts from the surface of the gate edge to the bulk Mg-doped layer edge. By optimizing both the length of Mg-doped layer, Lm, and the doping concentration, a 5.5 times and 3 times the reduction in the peak electric field near the drain side gate edge is observed as compared with those of the HEMTs with source-connected field plate structure and double field plate structure, respectively. In a device with VGS = -5 V, Lm 1.5 m, a peak Mg doping concentration of 8×10^17 cm-3 and a drift region length of 10 m, the breakdown voltage is observed to increase from 560 V in a conventional device without field plate structure to over 900 V without any area overhead penalty.

关键词： AlGaN/GaN HEMT reduced surface electric field Mg-doped layer breakdown voltage

Axial length and anterior chamber indices in elderly population: Tehran Geriatric Eye Study

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International Journal of Ophthalmology(English edition) 2023年第11期16卷 1876-1882页

作者： Hassan hashemi Samira Heydarian Alireza hashemi Mehdi Khabazkhoob Noor Research Center for Ophthalmic Epidemiology Noor Eye HospitalTehran ***Iran Department of Rehabilitation Science School of Allied Medical SciencesMazandaran University of Medical SciencesSari ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Department of Basic Sciences School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM:To determine the normative distribution of axial length(AL),anterior chamber depth(ACD),anterior chamber volume(ACV),anterior chamber angle(ACA),and some of their associated factors in subjects aged 60 and ***:In this cross-sectional study,160 clusters were sampled using multi-stage cluster sampling in Tehran,*** a preliminary interview,the participants underwent optometric examinations including visual acuity and refraction measurement followed by slit lamp ***,ocular imaging was done using the Pentacam AXL to measure AL,ACD,ACV,and ***:A total of 4519 eyes of 2436 participants were evaluated,of whom 58.0%(n=1412)were *** mean age of the subjects was 67.32±6.05y(range:60-95y).The mean AL,ACD,ACV,and ACA was 23.22 mm(23.18-23.27 mm),2.61 mm(2.59-2.62 mm),126.56 mm3(125.08-128.04 mm3),and 30.61°(30.3°-30.92°),*** the multivariable model,after adjusting for the effect of both eyes,the longest and shortest AL was seen in myopic and hyperopic subjects,***,ACD,ACV and ACA were significantly larger in men compared to women(Py,age and sex *** alteration in these parameters and their effect on refraction should be considered in this age group,especially in case of cataract surgery.

关键词： biometry elderly axial length anterior chamber depth

Residual refractive errors in pseudophakic eyes and related factors:a population-based study

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International Journal of Ophthalmology(English edition) 2023年第5期16卷 778-786页

作者： Hassan hashemi Alireza Jamali Farhad Rezavn Alireza hashemi Mehdi Khabazkhoob Noor Research Center for Ophthalmic Epidemiology Noor Eye HospitalTehran ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Department of Basic Sciences School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM: To determine residual refractive error after cataract surgery in pseudophakic eyes and its relationship with age, sex, and axial length(AL).METHODS: In this population-based cross-sectional study, the sampling was performed on individuals aged 60y and above in Tehran, Iran using a multi-stage stratified random cluster sampling method. Pseudophakic eyes with a best-corrected visual acuity of 20/32 or better were analyzed and their refractive results were ***: The mean spherical equivalent(SE) refraction was-0.34±0.97 diopters(D) and the mean absolute SE was 0.72±0.74 D with a median of 0.5 D. Moreover, 32.68%(n=546, 95%CI: 30.27%-35.08%), 53.67%(n=900, 95%CI: 51.23%-56.1%), 68.99%(n=1157, 95%CI: 66.96%-71.02%), and 79.73%(n=1337, 95%CI: 77.69%-81.76%) of the eyes had a residual SE within ±0.25, ±0.50, ±0.75, and ±1.00 D of emmetropia, respectively. According to the multiple logistic regression model, increasing age was associated with a statistically significant decrease in predictability for all cut points. Moreover, the predictability based on all cut points was significantly lower in individuals with an AL longer than 24.5 mm than in those with an AL between 22 to 24.5 ***: Based on the results, the accuracy of intraocular lens(IOL) power calculation is lower for those who underwent cataract surgery during the last 5y in Tehran, Iran. Among the most important influential factors, the choice of IOL or it's power disproportionate to eye conditions and age can be mentioned.

关键词： cataract surgery pseudophakic axial length residual refractive errors

Prevalence of retinal pathologies in people over 60 years:the Tehran Geriatrics Eye Study

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 721-728页

作者： Abolghasem Mortazavi Alireza hashemi Alirerza Jamali Hassan hashemi Mohammadreza Aghamirsalim Mehdi Khabazkhoob Department of Neurosurgery Sina HospitalTehran University of Medical SciencesTehran ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Rehabilitation Research Center Department of OptometrySchool of Rehabilitation SciencesIran University of Medical SciencesTehran ***Iran Noor Research Center for Ophthalmic Epidemiology Noor Eye HospitalTehran ***Iran Translational Ophthalmology Research Center Tehran University of Medical SciencesTehran ***Iran Department of Basic Sciences School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM:To determine the prevalence of some retinal pathologies in people over 60y and their association with demographic and ocular ***:A cross-sectional study was conducted in Tehran using multistage cluster *** selecting subjects aged 60 and over,optometric,and ophthalmic examinations were *** retinal examination,a 90 D lens was used and indirect ophthalmoscopy was performed after instilling tropicamide *** was done using the IOL Master for all ***:Of 3791 people that were invited through cluster sampling,3310 participated in the study(response rate=82%).The prevalence of retinal pigmented epithelium(RPE)change,drusen,geographic atrophy(GA),hypertensive retinopathy(HTR),nonproliferative diabetic retinopathy(NPDR),proliferative diabetic retinopathy(PDR),choroidal neovascularization(CNV),central retinal artery occlusion(CRAO),myopic retinopathy(MR),branch retinal vein occlusion(BRVO),and central retinal vein occlusion(CRVO)was 27.42%,11.08%,4.52%,3.03%,4.05%,0.54%,0.82%,0.39%,0.20%,0.49%,and 0.19%,*** removing the effect of age,the odds of NPDR were 1.68 times higher in women compared to men(P=0.014).After removing the effect of sex,the odds of drusen,RPE change,GA,CNV,BRVO,and CRVO increased with ***:There is a higher prevalence of RPE change,drusen,GA,CNV and a lower prevalence of MR and CRAO in the elderly population of Tehran aged over 60y compared to global average *** the correlation of most of the diseases with age and their effects on vision,attention should be paid to these diseases and the related screening programs to prevent vision impairment.

关键词： retinal pathologies cross-sectional study vision impairment

The prevalence of red-green color vision deficiency and its related factors in an elderly population above 60 years of age

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International Journal of Ophthalmology(English edition) 2023年第9期16卷 1535-1541页

作者： Hassan hashemi Aida Shahidi Alireza hashemi Alireza Jamali Abolghasem Mortazavi Mehdi Khabazkhoob Noor Research Center for Ophthalmic Epidemiology Noor Eye HospitalTehran ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Rehabilitation Research Center Department of OptometrySchool of Rehabilitation SciencesIran University of Medical SciencesTehran ***Iran Department of Neurosurgery Sina HospitalTehran University of Medical SciencesTehran ***Iran Department of Basic Sciences School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM:To determine the prevalence of red-green(RG)color vision deficiency(CVD)in an elderly population and its related ***:This report is a part of the Tehran Geriatric Eye Study:a cross-sectional population-based study that was conducted on the elderly population(≥60y)of Tehran,Iran using multi-stage stratified random cluster *** study participants underwent complete ocular examination,including the measurement of uncorrected and bestcorrected visual acuity,objective and subjective refraction,and slit-lamp *** color vision was tested using Ishihara plates with the near optical correction in ***:Of the 3791 invitees,3310 participated in the *** data of 2164 individuals were analyzed after applying the exclusion *** prevalence of R-G CVD was 3.73%(95%CI:2.37%–5.09%)in the whole sample;the prevalence of protanomaly,protanopia,and deuteranopia was 1.51%,1.76%,and 0.45%,*** prevalence of R-G CVD was significantly higher in males than in *** prevalence of RG CVD increased with advancing age from 2.91%in the age group 60–64y to 5.8%in the age group≥80y(P=0.070).According to the multiple logistic regression model,male sex,and glaucoma were significantly related to RG *** age and hypertension also had a marginally significant relationship with RG ***:Changes in color vision occur in the elderly due to the aging process and some physiological and pathological *** the change in visual perception may affect the person’s performance,this aspect of the visual system’s function should also be taken into consideration in the examinations of the elderly.

关键词： color vision population-base study protanomaly protanopia deuteranopia elderly