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基于三闭环控制系统的BLDC转矩脉动抑制分析

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兰州文理学院学报（自然科学版） 2023年第4期37卷 68-73页

作者：曹子沛 annisa binti jamali 任远林沐娟安徽工商职业学院应用工程学院安徽合肥231131 砂拉越大学工程学院砂拉越州古晋市94300

为解决无位置传感器无刷直流电机存在转矩脉动的问题,本文基于传统的双闭环控制,增加功率环,建立三闭环控制系统,利用分阶段控制策略,减小电机的母线电流脉动和转矩脉动.首先利用MATLAB/Simulink软件建立传统的双闭环控制模型,提出功率... 详细信息

为解决无位置传感器无刷直流电机存在转矩脉动的问题,本文基于传统的双闭环控制,增加功率环,建立三闭环控制系统,利用分阶段控制策略,减小电机的母线电流脉动和转矩脉动.首先利用MATLAB/Simulink软件建立传统的双闭环控制模型,提出功率抑制闭环控制的研究方法以及推导公式;然后建立三闭环控制系统模型,通过仿真结果验证结论;最后利用DSPIC33F单片机控制平台验证了控制策略能够很好抑制转矩脉动,改进后的系统具有较好的鲁棒性.

关键词：转矩脉动 BLDCM 无位置传感器三闭环控制方法

独立或共享租赁模式下储能电站调峰的经济性分析

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太阳能 2023年第7期 40-53页

作者：曹子沛 annisa binti jamali 沐娟任远林安徽工商职业学院应用工程学院合肥231131 砂拉越大学工程学院砂拉越州999004

2021年,中国多个省市发布政策要求光伏发电项目需配置一定比例的储能,储能配置比例为10%~20%,配置时长在1~4 h之间。储能的配置方式既可以是与光伏发电系统配套设置,也可以是由独立或共享租赁模式的储能电站进行储能。针对中国各地区采... 详细信息

2021年,中国多个省市发布政策要求光伏发电项目需配置一定比例的储能,储能配置比例为10%~20%,配置时长在1~4 h之间。储能的配置方式既可以是与光伏发电系统配套设置,也可以是由独立或共享租赁模式的储能电站进行储能。针对中国各地区采用电化学储能的独立储能及共享租赁储能电站调峰的政策进行分析,并对储能电站投资关键边界条件(比如:调峰补贴、调峰保障小时数、租赁价格、储能成本等)变化对项目内部收益率的影响进行定量测算和分析。分析结果显示:共享租赁储能电站在采用租赁叠加调峰补贴方式后已具备投资价值,而独立储能电站仅依靠调峰补贴暂不具备投资价值。

关键词：电化学储能共享租赁储能电站独立储能电站调峰内部收益率经济性

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

Survivability evaluation for networks carrying complex traffic flows

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Digital Communications and Networks 2023年第2期9卷 534-544页

作者： Amin jamali Mehdi Berenjkoub Hossein Saidi Behrouz Shahgholi Ghahfarokhi Faculty of Computer Engineering University of IsfahanIsfahan***Iran Department of Electrical and Computer Engineering Isfahan University of TechnologyIsfahan***Iran

The capability of a system to fulfill its mission promptly in the presence of attacks,failures,or accidents is one of the qualitative definitions of *** this paper,we propose a model for survivability quantification,which is acceptable for networks carrying complex traffic *** network traffic is considered as general multi-rate,heterogeneous traffic,where the individual bandwidth demands may aggregate in complex,nonlinear *** probability is the chosen measure for survivability *** study an arbitrary topology and some other known topologies for the *** and dependent failure scenarios as well as deterministic and random traffic models are ***,we provide survivability evaluation results for different network *** results show that by using about 50%of the link capacity in networks with a relatively high number of links,the blocking probability remains near zero in the case of a limited number of failures.

关键词： Blocking probability Complex traffic Link failure Network survivability Disaster recovery Information assurance

Forty Years of Air Temperature Change over Iran Reveals Linear and Nonlinear Warming

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Journal of Meteorological Research 2022年第3期36卷 462-477页

作者： Majid KAZEMZADEH Zahra NOORI Sadegh jamali Abdulhakim M.ABDI Faculty of Natural Resources University of Tehran77871-31587KarajIran Department of Technology and Society Lund UniversitySE-22100LundSweden Centre for Environmental and Climate Science Lund UniversitySE-22362LundSweden

Spatiotemporal analysis of long-term changes in air temperature is of prime importance for climate change research and the development of effective mitigation and adaptation *** there are considerable studies on air temperature change across the globe,most of them have been on linear trends and time series analysis of nonlinear trends have not received enough ***,spatiotemporal patterns of monthly and annual mean(Tmean),maximum(T_(max)),and minimum(T_(min))air temperature at 47 synoptic stations across climate zones in Iran for a 40-yr period(1978–2017)are analyzed.A polynomial fitting scheme(Polytrend)is used to both monthly and annual air temperature data to detect trends and classify them into linear and nonlinear(quadratic and cubic)*** significant(non-significant)trends in Tmean,T_(max),and T_(min) across all climate zones are 41.1%(58.9%),34.1%(65.9%),and 46%(54%),*** highest magnitude of increasing trends is observed in the annual T_(min)(0.47℃decade−1)and the lowest magnitude is for the annual T_(max)(0.4℃decade−1).Across the country,increasing trends(=37.2%)have higher spatial coverage than the decreasing trends(=3.2%).Warming trends in Tmean(65.3%)and T_(min)(73.1%)are mainly observed in humid climate zone while warming trends in T_(max) are in semi-arid(43.9%)and arid(34.1%)*** change with a positive trend is predominant in all Tmean(56.7%),T_(max)(67.8%),and T_(min)(71.2%)and for both monthly and annual ***,the linear trends have the highest warming rate in annual T_(min)(0.83℃decade^(−1))and Tmean(0.46℃decade^(−1))whereas the nonlinear trends have the highest warming rate in annual T_(max)(0.52℃decade^(−1)).The linear trend type is predominant across the country especially in humid climate zones whereas the nonlinear trends(quadratic and cubic)are mainly observed in the arid climate *** study highlights nonlinear changes and spatiotemporal trends in air temperature in Iran an

关键词： linear trends nonlinear trends time series analysis air temperature Polytrend Iran

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

Experimental Testing of Cellular Construction Materials Containing Flax Particles

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Fluid Dynamics & Materials Processing 2023年第3期19卷 723-741页

作者： Hamadou-Ali Mohamed Benazzouk Amar Haïkel Ben Hamed Arash jamali Laboratoire des Technologies Innovantes(UR-UPJV 3899)-UPJV Amiens80000France Plateforme de Microscopie Electronique-UPJV HUB de l’Energie80039Amiens

The feasibility of a sustainable non-autoclaved cellular concrete,based on flax vegetable co-products,for the production of usable specimen in the lightweight construction field,has been investigated *** produced specimen,containing various volume ratios of flax particles with respect to preformulatd Tradical PF70 lime binder of 0,1,and 2,were lightened by creating a porous structure in the matrix through the addition of 0.3%*** powder(able to react with calcium hydroxide from the binder and result in microscopic air-bubbles).Fresh and hardened specimen properties,including hydration,fresh density,porosity,hardened density,compressive and flexural strengths,toughness energy,and dry thermal conductivity at different temperatures,were assessed for varying flax-to-binder *** have shown that the addition of Aluminum powder leads to restrain the setting time delay of binder-based ***,the hardened material displays a significant decrease in specimen density,thereby resulting in a compressive strength level compatible with that required in the cellular construction materials *** also highlighted the ability of added flax to induce a change in the specimen from brittle to ductile ***,a high degree of thermal insulation can be achieved,which makes the cellular specimen based on flax particle suitable as insulated-bearing walls material.

关键词： Flax particles cellular concrete lightening porous structure physico-mechanical properties thermal conductivity

Auto-refraction versus subjective refraction in different phakic and pseudophakic conditions:the Tehran Geriatric Eye Study(TGES)

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International Journal of Ophthalmology(English edition) 2023年第8期16卷 1309-1316页

作者： Hassan Hashemi Amir Asharlous Alireza jamali Abolghasem Mortazavi Alireza Hashemi 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 compare the subjective refraction data with non-cycloplegic auto-refraction findings in the geriatric population above 60 years of age according to the different crystalline lens ***:This report is a part of the Tehran Geriatric Eye Study(TGES)that was conducted from January 2019 to January 2020 on elderly population 60 years of age and above in *** samples were selected by multistage stratified random cluster *** 3791 individual invitees,3310(response rate:87.3%)participated in this *** study participants underwent non-cycloplegic autorefraction(auto-refractometer/keratometer Nidek ARK-510)and subjective ***:Regarding the sphere,eyes with mixed cataract had the worst limits of agreement(LoA:-1.24 to 0.87)and the best agreement was related to the pseudophakic eyes(LoA:-0.83 to 0.54).The highest(0.27±0.31 D)and lowest(0.21±0.27 D)differences between the two methods regarding the cylinder power were observed in eyes with cortical cataract and normal eyes,*** worst LoA between the two methods in measuring the cylinder power was related to the eyes with mixed cataract(LoA:-0.44 to 0.96).Regarding the J0(horizontal/vertical components of astigmatism),the mean values of J0 obtained by auto-refraction were tended more toward against the rule direction in all crystalline lens conditions,and the two methods had the greatest difference in cortical cataract cases(0.05±0.17 D).Regarding the J45(oblique components of astigmatism),the lowest(0±0.11 D)and highest(-0.01±0.12 D)differences were observed in normal eyes and eyes with cortical cataract,***:The auto-refractometer/keratometer Nidek ARK-510 results in the elderly with different phakic and pseudophakic conditions do not correspond well with subjective refraction *** discrepancy in spherical findings is more pronounced in individuals with mixed cataract than in other cases.

关键词： refraction subjective geriatric noncycloplegic autorefraction

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