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Applying Sliding Mode Control to Suppress Double Frequency Voltage Ripples in Single-phase Quasi-Z-source Inverters

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 671-681页

作者： Jaber Merrikhi Ahangarkolaei mahdi izadi Tohid Nouri Department of Electrical Engineering Sari BranchIslamic Azad UniversitySariIran Department of Electrical Engineering Shahriar BranchIslamic Azad UniversityShahriarIran

The inherent double-line frequency ripple(DFR)of the single-phase quasi-Z-Source inverter(qZSI)strongly affects performance and design of the whole system,which requires hardware improvement methods such as additional semiconductor components or increasing the volume of capacitors and *** a result,hardware solutions increase the price,and the volume and also reduces reliability of the *** this paper,as a non-hardware solution,a sliding mode control(SMC)method is presented to control the voltage of the qZSI *** suppress the DFR,a second-order harmonic is injected into the capacitor reference *** and experimental results show that the introduced controller will have satisfactory results in reducing the DFR without any hardware changes in the qZSI,such as increasing the volume of the capacitor and inductor,adding a semiconductor,or increasing the frequency.A simulation model and experimental prototype are provided to demonstrate the validation of the effectiveness of the proposed controller.

关键词： Double-frequency ripple quasi-Z-source inverter sliding mode control

Introduction of New Method on Engineering Risk Assessment:Engineering Errors and Effects Analysis(3EA)

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Management Studies 2018年第6期6卷 527-530页

作者： Mohammad mahdi izadi Shahid Beheshti University of Medical Science Nargan Co. TehranIran

Construction and commissioning accidents investigation shows that engineer’s errors in basic and detailed phases are the main *** will be gained more efficiency of investment when a relevant method is applied for error identification and risk assessment in basic and detailed *** of risk assessment methods are related to construction phase,meanwhile hidden risks that were happen in previous phases cannot be found by these *** HAZOP study can be applied in detail phase but it can help to find process *** of identifying risks in basic and detailed phases is to apply preventive actions against birth and grows *** risk assessment method can reduce costs and improve environmental protection,safety,and reliability of *** main purpose of this study is to identify engineer’s errors and analyse their HSE *** method is applied in seven oil and gas engineering projects in Iran,raising the level of engineer’s attention to safety precautions and environmentally-friendly design,reducing the cost of improving the level of safety and environmental protection,improving environmental protection,safety,and design reliability,and improving procedures related to design process and control have been achieved.

关键词： Engineering Errors and Effects Analysis(3EA) engineering error detailed effectiveness control risk assessment

Effect of Time, Cultivar and Rootstock on Success of Rose Propagation through Stenting Technique

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American Journal of Plant Sciences 2014年第11期5卷 1644-1650页

作者： Zeinab izadi Hossein Zarei mahdi Alizadeh Department of Horticultural Sciences Gorgan University of Agricultural Sciences and Natural Resources Gorgan Iran

An experiment was undertaken to study the effects of two grafting times (1st of June and end of September) as well as kind of rootstock on growth and rooting of rose stentlings. Two Rosa species i.e. R. canina and R. manetti were selected as rootstock and three different hybrid tea rose cultivars namely Avalanch, Peach Avalanch and Dolcevita were grafted on them as scion through omega and splice techniques. The growth parameters were collected 57 days after grafting. The highest average of rooting, healing percentage, numbers of root, shoot and leaves were seen in September grafted plants. In overall Rosa canina was the best rootstock for Avalanch cultivar. Other observations did not lead to any prominent result as it varied with time of grafting, scion and rootstock cultivars.

关键词： Rootstock Rose Scion Stenting Grafting Time

Role of interlayer composition in microstructure and mechanical properties during TLP bonding of GTD-111/IN-718 superalloys

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Transactions of Nonferrous Metals Society of China 2022年第3期32卷 908-926页

作者： Ali izadi GHAHFEROKHI Masoud KASIRI-ASGARANI Kamran AMINI mahdi RAFIEI Reza EBRAHIMI-KAHRIZSANGI Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Center for Advanced Engineering Research Majlesi BranchIslamic Azad UniversityIsfahanIran

An investigation was carried out to assess the applicability of transient liquid phase bonding of two dissimilar super-alloys with different interlayers. The effect of using three types of interlayer such as BNi-2, BNi-3, and BNi-9 on microstructure and mechanical properties was studied in the GTD-111/IN-718 system at 1100 ℃ for different bonding time. To determine the compositional changes and microstructure in the joint region, field emission scanning electron microscopy equipped with energy dispersive spectroscopy was utilized. The formation of Ni_(3)B in the athermally solidified zone(ASZ) is controlled by the B content and, accordingly, the morphology of Ni_(3)Si is governed by the Si content. The Cr content might impede the relocation of B from the interlayer into the base metal and the formation of CrB inside the ASZ is dominated by the Cr content. The high micro-hardness of the eutectic compounds is originated from the formation of boride matrixes such as Ni or Cr boride. The shear strength of the joint using BNi-9 after the completion of isothermal solidification is lower compared that that using BNi-3 and BNi-2, which could be related to the absence of Si in the filler metals constituent and the significant presence of Cr in BNi-9.

关键词： transient liquid phase bonding Ni-based superalloy isothermal solidification Ni-B compounds