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Effect of livestock grazing and human uses on herbaceous species diversity in oriental beech(Fagus orientalis Lipsky) forests, Guilan, Masal, northern Iran

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Journal of Forestry Research 2014年第2期25卷 455-462页

作者： Sepide Sadat Ebrahimi Hassan Pourbabaei David Potheir ali omidi Javad Torkaman Department of Forestry Natural Resource FacultyUniversity of Guilan Centre d’étude de la forêt (CEF) and Département des sciences du boiset de la forêtPavillon Abitibi-Price Department of Forestry Natural Resources Office

Plant diversity plays key ecological roles in forest ecosystems, including influencing succession, resilience and nutrient cycling. This study was conducted to investigate the effect of livestock grazing and human uses on herbaceous species diversity. We surveyed 50 ha of protected area and 50 ha of unprotected area to evaluate herbaceous species diversity in oriental beech （Fagus orientalis Lipsky） forests in northern Iran. We calculated and compared three indices each of diversity and evenness, and species richness between the two areas. Herbaceous cover was higher in the unprotected area while leaf litter depth and tree canopy cover were higher in the protected area. The diversity indices, H （Shan- non-Wiener index ）, N~ （McArthur index）, N2 （Hill＇s index）, EQ （Modified Nee index）, E,ar （Smith-Wilson index）, E5 （modified index of Hill） and R=S （species richness） and species richness R=S were greater in the protected area than in the unprotected area, suggesting that protection from grazing results in increased numbers of plants and species. The effect of land protection on plant diversity was more pronounced for evenness than for species richness and the positive correlation between diversity and evenness indices was higher than that between diversity and richness.

关键词： grazing human uses richness evenness beech forests Caspianforest

Overview of the Importance of Intelligent Approaches on Machinery Faults Diagnosis and Prediction Based on Prognostic and Health Management/Condition-Based Maintenance

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Journal of Donghua University(English Edition) 2018年第3期35卷 270-273页

作者： omidi ali LIU Shujie School of Mechanical Engineering Dalian University of TechnologyDalian 116024China

Condition monitoring is increasingly used to anticipate and detect failures of industrial *** of machines can cause high maintenance or replacement *** neglected,it may result in catastrophic accidents leading to production *** potential failure would negatively affect the profitability of the company,including production shut down,cost of spare parts,cost of labor,damage of reputation,risk of injury to people and the *** recent years,condition-based maintenance( CBM) and prognostic and health management( PHM) are developed and formed a strong connection among science,engineering,computer,reliability,communication,management,*** maintenance management systems( CMMS) store a lot of data regarding the fault diagnosis and life prediction of the machinery ***'s too necessary to uncover useful knowledge from the huge amount of ***'s vital to find the ways to obtain useful and concise information from these *** information can be of great influence in the decision making of *** article is a review of intelligent approaches in machinery faults diagnosis and prediction based on PHM and CBM.

关键词： condition-based maintenance(CBM) prognostic and health management(PHM) machinery fault diagnosis data mining data processing

Long-term effect of fire on herbaceous species diversity in oriental beech (Fagus orientalis Lipsky) forests in northern Iran

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Forestry Studies in China 2012年第4期14卷 260-267页

作者： Mohammad Naghi ADEL Hassan POURBABAEI ali omidi David POTHIER Department of Forestry Natural Resources FacultyUniversity of Guilan Department of Forestry Natural Resources Office Centre d'étude de la forêt (CEF) et Département des sciences du bois et de la forêt Pavillon Abitibi-Price2405 rue de la TerrasseUniversité Laval

We studied the long-term impacts of natural burning on herbaceous species diversity 37 years after a fire occurred in the Roudbar forests of Guilan Province, northern Iran. Numerous studies have examined short-term changes in understory vegetation following wildfire; however, very few long-term studies are available or changes inferred from retrospective studies based on chro- nosequences. For this study, 170 ha of forest （85 ha, burned areas; 85 ha, unburned areas） were surveyed. Because the 1000 m2 plots were too large for detailed measurements of herbaceous species, we determined a sub-sample size according to the Whittaker＇s nested plot sampling protocol and minimal areas method. Hence, sub-plots of 32 m2 were used for herbaceous species measurements, which consisted of percent cover of each species based on the Domin criterion. We measured plant diversity （Shannon-Wiener index）, spe- cies richness （Margalef＇s index）, and evenness （Smith-Wilson index）. Mean percent cover, together with diversity, richness and even- ness, increased markedly in burned areas compared to unburned controls. This suggests that the biodiversity of these forests could be restored within 37 years after fire. However, the abundance of invasive species such as Rubus fruticosus and Bromus benekenii increased significantly in burned areas, but these could be controlled by relevant silvicultural operations.

关键词： fire diversity richness evenness beech forest northern Iran

Over-mature beech trees (Fagus orientalis Lipsky) and close-to-nature forestry in northern Iran

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Journal of Forestry Research 2012年第2期23卷 289-294页

作者： Mostafa Moradi Mohammad R.Marvie Mohadjer Kiomars Sefidi Mahmoud Zobiri ali omidi Faculty of Natural Resources University of TehranKarajIran Faculty of Agriculture University of Mohaghegh ArdabiliArdabilIran FRWO(Forests Range and Watershed Management Organization of Iran)RashtIran

Oriental Beech is the most important commercial tree species in northern Iran. In recent years wood production companies interested in felling large beech trees for profit have challenged advocates of close-to-nature silviculture who favor conservation. Our study objective was to assess the economic value of over-mature beech trees by relating tree diameter （DBH） to amount of decay. Based on the location of onset of decay, we categorized three types of decay as stump, stem, and crown decay. Trees of greater diameter （age） typically showed greater decay in the stem. Percent of decayed volume, diameter of decayed tissue, and length of decay in tree stems varied between 0.5%-64.3%, 15 cm-75 cm, and 2.0-19.5 m, respectively. With increasing trunk diameter, the propor- tion of truck decay increased. Red heart and dark red heart constituted 25% and 14.3% of sampled trees, respectively. However, we found no correlation between intensity of stem decay and morphological charac- teristics of trees. Seedlings were not abundant around the bases of over-mature trees, suggesting that the trees did not contribute to regeneration of the stand. Beech trees of diameter 〉1 m do not provide valu- able round wood for industries and cause to raise wood production costs. We recommend that these trees 〉1 m DBH should be retained in forest stands because of their low commercial value but high ecological and conservational values such as maintaining biodiversity in forest ecosystems.

关键词： Caspian forests close-to-nature forestry Fagus orientalis red heart and stem decay Iran

基于轴承振动分析的智能离心泵寿命研究及故障诊断

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基于轴承振动分析的智能离心泵寿命研究及故障诊断

作者： ali omidi 大连理工大学

学位级别：硕士

离心泵广泛应用于石油、石化、化工等流体领域,是重要的旋转机器之一。在工作过程中,由于泵的失效会导致生产线停止运转,因此,泵失效能力的早期检测可以保证生产线的连续性,同时也防止了泵本身的严重损坏,而监测离心泵的健康状况对于防... 详细信息

离心泵广泛应用于石油、石化、化工等流体领域,是重要的旋转机器之一。在工作过程中,由于泵的失效会导致生产线停止运转,因此,泵失效能力的早期检测可以保证生产线的连续性,同时也防止了泵本身的严重损坏,而监测离心泵的健康状况对于防止泵的意外停机至关重要。振动信号处理和技术分类的组合可以更好、更可靠的进行离心泵故障诊断。振动信号处理、尺寸测量技术和分类技术的应用是离心泵故障诊断中更值得深入探索的一个开放研究领域。本文研究基于轴承振动分析的离心泵寿命研究及故障诊断,在基于条件的维护(CBM)中,预测及健康管理(PHM)的加入对系统的有效保护有重要作用。在此之前,直接用测量的实际数值与PHM匹配的方法会引入外部噪音,基于此模型的维护策略并不理想。为了解决上述问题,本论文提出基于条件维护(CBM)和预测与健康管理(PHM)的结合,建立一种新的故障诊断方法,从轴承的数据中提取隐藏知识以提高离心泵寿命预测性能的工具。应用这种数据处理方法,在使用数据作为PHM输入之前,先消除外部噪声并进行数据匹配。我们采用泵轴承振动数据来验证模型。将该模型与两个相似模型进行了比较,通过建立一个智能网络,隐藏数据信号,获取更多清晰的知识预测。结果表明,我们所提出的模型可以更精确地进行预测。该方法可以期待用于提高设备管理的有效性、可靠性、安全性,最终提高离心泵的使用寿命。

关键词：基于条件的维修(CBM) 预测与健康管理(PHM.) 故障诊断数据挖掘数据处理智能条件预测

Missed estradiol determination resulting in oocyte retrieval and embryo development following controlled ovarian hyperstimulation at early pregnancy: Case report

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Asian pacific Journal of Reproduction 2018年第3期7卷 143-144页

作者： Maryam Eftekhar Azam Agha-Rahimi Mohammad ali Khalili Marjan omidi Department of Obstetrics and Gynecology Shahid Sadoughi University of Medical SciencesYazdIran Research and Clinical Center for Infertility Yazd Reproductive Sciences InstituteShahid Sadoughi University of Medical SciencesYazdIran Department of Reproductive Biology Shahid Sadoughi University of Medical SciencesYazdIran

This paper is a case report on the success of oocyte retrieval and good quality embryo development following controlled ovarian hyperstimulation at early pregnancy. A 30-year-old patient underwent controlled ovarian hyperstimulation by gonadotropin-releasing hormone agonist long protocol. On the day of oocyte collection, a 5-week gestational sac was observed by exact sonography monitoring. However, via ultrasound guided follicle puncture, 7 oocytes were collected. After intarcytoplasmic sperm injection, 3 developed good quality embryos were cryopreserved. Moreover, the natural pregnancy was continued and finally a healthy live birth was achieved. Despite physiological hormonal changes during pregnancy, the follicular growth occurred and followed by oocyte retrieval and embryo development, subsequently.

关键词： Controlled ovarian hyperstimulation Oocyte Embryo Pregnancy

Epicardial Versus Endocardial Pacemakers in the Pediatric Population:A Comparative Inquiry

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Congenital Heart Disease 2021年第6期16卷 573-584页

作者： Mohammadrafie Khorgami ali Sadeghpour Tabaei Elio Caruso Silvia Farruggio Negar omidi Maryam Moradian Behzad Mohammadpour Ahranjani Zahra Khajali Rahele Zamani Cardiovascular Medical and Research Center Iran University of Medical SciencesTehranIran Cardiovascular Surgery Department Rajaie Cardiovascular Medical and Research CenterIran University of Medical SciencesTehranIran Department of Pediatric Cardiology Mediterranean Pediatric Cardiology Center“Bambin Gesù”San Vincenzo HospitalTaorminaItaly Cardiac Primary Prevention Research Center Tehran Heart Center and Department of CardiologySchool of MedicineTehran University of Medical SciencesTehranIran Pediatric Cardiology Bahrami Children’s HospitalTehran University of Medical ScienceTehranIran Adult Congenital Heart Disease Department Rajaie Cardiovascular Medical and Research CenterIran University of Medical SciencesTehranIran

Background:Most children in need of cardiac pacemakers remain dependent on the function of the permanent from childhood to *** sought to evaluate and compare the function between epicardial and endocardial pacemakers in pediatric groups with different ***:Between 2012 and 2018,this single-canter study evaluated 44 pediatric patients with indications for epicardial or endocardial ***:The 2 groups,at a median age of 5(0.1–16)years,were compared concerning the characteristics of the leads used(n=80:bipolar,unipolar,steroid-eluting,and non–steroid-eluting),survival data,and *** reason for pacemaker implantation was congenital complete heart block in 11(25%)cases and postoperative heart block in 33(75%)*** commonest congenital heart disease accompanied by postoperative block was the ventricular septal *** the endocardial lead group,the mean ventricular pacing threshold immediately after the implantation and during the follow-up was less than that in the epicardial lead group(0.75 vs.0.81 V;P=0.01 and 0.8 vs.2.4 V;P=0.001).During the follow-up,the mean battery longevity was better in the endocardial group(last visit:6.7 endocardial vs.3.3 years epicardial).Lead failure was commoner in the epicardial pacemaker,and chronic high-pacing threshold pattern was seen in 14 patients in this *** 3 years,freedom from lead failure was 94%and 63%in the endocardial and epicardial ***:Pacemakers with endocardial bipolar steroid-eluting leads showed better lead characteristics regarding survival and battery longevity than epicardial pacemakers without these lead *** appropriate pacemaker type should be selected based on the patient’s condition.

关键词： Pacemaker congenital heart defects cardiac pacing pediatrics

Hybrid External Fixation for Open Severe Comminuted Fractures of the Distal Femur

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Surgical Science 2013年第2期4卷 176-183页

作者： Ebrahim Ghayem Hassankhani ali Birjandinejad Farzad omidi Kashani Golnaz Ghayem Hassankhani Department of Orthopedics and Spine Surgery Orthopedic Research Center Imam Reza Hospital Mashhad University of Medical Sciences Mashhad Iran Department of Orthopedics Surgery Imam Reza Hospital Mashhad University of Medical Sciences Mashhad Iran Department of Orthopedics Surgery Shahid Kamiab Hospital Mashhad University of Medical Sciences Mashhad Iran Mashhad University of Medical Sciences Mashhad Iran

Background: The treatment of distal femoral open comminuted fractures is a major problem for orthopedic surgeon. The basic and important aim in treatment of these fractures is to assemble the condylar fragments and then fix the condyles to the femoral shaft by minimum handling of the bone and soft tissues. Objectives: To evaluate the treatment of distal femoral open comminuted fractures (type C2 and C3) with hybrid external fixator. Methods: Thirty-four patients with distal femur open comminuted fracture (type C2 and C3) were treated by hybrid external fixator between January 2005 and December 2008. All of the fractures were opened with extension to joint surface. 30 patients were male and 4 were female. Their average age was 30.5 years (17 to 72 years). Average follow up period was 36 months. 12 patients had isolated fracture and 22 patients had multiple fractures. The bony and functional results were evaluated by the association for the study and application of the method of Ilizarov (ASAMI) protocol and knee society score. Results: 29 out of 34 fractures (85%) had union without bone grafts. Average time of union was 6.1 months (4 - 19 ms). The average knee range of motion was 87.5 degrees (30 - 115 degrees). The bony results were excellent in 24 patients (70.5%), good in 6 (17.7%), fair in 2 (5.9%), and poor in 2 (5.9%), and the functional results were excellent in 10 (29.4%) patients, good in 14 (41.2%), fair in 6 (17.6%), and poor in 4 (11.8%), and the functional results were excellent in 10 (29.4%) patients, good in 14 (41.2%), fair in 6 (17.6%), and poor in 4 (11.8%) according to ASAMI protocol. According to the knee society score the functional results were excellent in 9 (26.44%) patients, good in 13 (38.26%), fair in 7 (20.6%), and poor in 5 (14.7%). Conclusion: Hybrid external fixator is an effective method for treatment of distal femoral open comminuted fractures (type C2 and C3) and may be considered as an alternative surgical methods in the management

关键词： Hybrid External Fixator Open Fractures Distal Femoral Fracture Type C2 and C3

Optimization of Ilmenite Dissolution by Synergistic Effect of Oxalic Acid and Hydrochloric Acid for Preparing Synthetic Rutile

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International Journal of Nonferrous Metallurgy 2018年第3期7卷 25-38页

作者： Mohammad Hasan omidi Omid Salmani Nuri Hassan Tavakoli Department of Chemistry Faculty of Science University of Guilan Guilan Iran Department of Mining and Metallurgical Engineering Amirkabir University of Technology Tehran Iran Department of Physics and Chemistry Faculty of Basic Sciences Imam Ali University Tehran Iran

This study was carried out to investigate the interaction of oxalic acid with hydrochloric acid to attain the better performance for iron dissolution in comparison to absence of oxalic acid. The effects of oxalic acid on ratio of hydrochloric acid, acid concentration, ratio of liquid to solid, temperature and dissolution time are investigated for the dissolution of Fe and Ti from ilmenite to produce synthetic rutile. The DX7 software basing on an experimental design method with the central composite of response surface design is applied to specify the effects of the parameters and to optimize the leaching process. The optimum condition was determined by analysis of variance (ANOVA), indicating that the ratio of oxalic acid to hydrochloric acid for Fe dissolution and acid concentration for Ti dissolution were the most effective parameters. The results showed that the dissolution of Fe and Ti in 30% (w/w) hydrochloric acid solution was only 48.65% and 5.14%, respectively, while at the same condition and in the presence of oxalic acid with twice the ratio, these values are increased to 78.65% and 12.06%, respectively. The optimum values of parameters were as follows: oxalic acid to hydrochloric acid ratio (2:1), acid concentration (30%), ratio of liquid to solid (10), temperature (160 °C), and dissolution time (3 h). By applying the optimized parameters, Fe and Ti dissolution of 97.15% and 2.8% were predicted by the software with a desirability of 0.745. The results of leaching tests indicated that the Fe and Ti dissolution of 97.58% and 2.43%, were achieved, respectively, which are very close to the predicted value.

关键词： Ilmenite Oxalic Acid Hydrochloric Acid Synthetic Rutile Leaching