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Frontiers of Nursing 2024年第3期11卷 319-326页

作者： Mohammad Ali Mohammadi mehdi heidarzadeh Saeed Mehri Mahmood Shamshiri Department of Medical-Surgical Nursing School of Nursing and MidwiferyArdabil University of Medical SciencesArdabil ***Iran Department of Emergency Nursing School of Nursing and MidwiferyArdabil University of Medical SciencesArdabil ***Iran Department of Critical Care Nursing School of Nursing and MidwiferyArdabil University of Medical SciencesArdabil ***Iran

Objective:To explore the meaning of care experienced by people with blindness in ***:Interpretive phenomenology along with the 6-step method of van Manen was used to conduct the *** purposeful sampling,15 people with legal blindness were *** analysis was used to isolate the meaning of ***:Five themes emerged:(a)nurses in the eyes of patients with blindness;(b)negligence in the caring moments;(c)being cared for in ambiguity;(d)Uncoordinated care;and(e)Psychological discomfor *** sub-themes were condensed into an overarching theme titled as“marginalized patients inside the stereotypical healthcare system.”Conclusions:Lived experiences of patients with blindness revealed that hospitals provide stereotypic or inappropriate care for this minority group in *** professionals par ticularly nurses should be skilled to provide person-centered and coordinated care for patients with blindness.

关键词： hospitalization lived experience meaning of care people with blindness phenomenology

A methodology for damage evaluation of underground tunnels subjected to static loading using numerical modeling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1993-2005页

作者： Shahriyar heidarzadeh Ali Saeidi Rock Mechanics Engineer AtkinsRéalisMontrealQuebecCanada Department of Applied Sciences Universitédu QuébecàChicoutimiChicoutimiQuebecCanada

We have proposed a methodology to assess the robustness of underground tunnels against potential *** involves developing vulnerability functions for various qualities of rock mass and static loading *** account for these variations,we utilized a Monte Carlo Simulation(MCS)technique coupled with the finite difference code FLAC^(3D),to conduct two thousand seven hundred numerical simulations of a horseshoe tunnel located within a rock mass with different geological strength index system(GSIs)and subjected to different states of static *** quantify the severity of damage within the rock mass,we selected one stress-based(brittle shear ratio(BSR))and one strain-based failure criterion(plastic damage index(PDI)).Based on these criteria,we then developed fragility ***,we used mathematical approximation techniques to produce vulnerability functions that relate the probabilities of various damage states to loading intensities for different quality classes of blocky rock *** results indicated that the fragility curves we obtained could accurately depict the evolution of the inner and outer shell damage around the ***,we have provided engineers with a tool that can predict levels of damages associated with different failure mechanisms based on variations in rock mass quality and in situ stress *** method is a numerically developed,multi-variate approach that can aid engineers in making informed decisions about the robustness of underground tunnels.

关键词： Fragility curves Underground tunnels Vulnerability functions Brittle damage FLAC3D Numerical modeling

Determination of uncertainties of geomechanical parameters of metamorphic rocks using petrographic analyses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 345-364页

作者： Behzad Dastjerdy Ali Saeidi Shahriyar heidarzadeh Department of Applied Sciences University of Quebec at ChicoutimiSaguenayQCCanada SNC-Lavalin MontrealCanada

Geomechanical parameters of intact metamorphic rocks determined from laboratory testing remain highly uncertain because of the great intrinsic variability associated with the degrees of *** aim of this paper is to develop a proper methodology to analyze the uncertainties of geomechanical characteristics by focusing on three domains,*** treatment process,schistosity angle,and ***,the variabilities of the geomechanical laboratory data of Westwood Mine(Quebec,Canada)were examined statistically by applying different data treatment techniques,through which the most suitable outlier methods were selected for each parameter using multiple decision-making criteria and engineering *** indicated that some methods exhibited better performance in identifying the possible outliers,although several others were unsuccessful because of their limitation in large sample *** well-known boxplot method might not be the best outlier method for most geomechanical parameters because its calculated confidence range was not acceptable according to engineering ***,several approaches,including adjusted boxplot,2MADe,and 2SD,worked very well in the detection of true ***,the statistical tests indicate that the best-fitting probability distribution function for geomechanical intact parameters might not be the normal distribution,unlike what is assumed in most geomechanical ***,the negative effects of schistosity angle on the uniaxial compressive strength(UCS)variabilities were reduced by excluding the samples within a specific angle range where the UCS data present the highest ***,a petrographic analysis was conducted to assess the associated uncertainties such that a logical link was found between the dispersion and the variabilities of hard and soft minerals.

关键词： Intact rock parameters Natural variabilities Outlier detection methods Uncertainties Westwood mine Mineralogy

Correlation between process parameters,grain size and hardness of friction-stir-welded Cu-Zn alloys

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Rare Metals 2018年第5期37卷 388-398页

作者： Akbar heidarzadeh Tohid Saeid Faculty of Materials Engineering Sahand University of Technology

In this study, the effects of tool rotational speed, tool traverse speed, and Zn content on the grain size and hardness of the friction-stir-welded （FSWed） Cu-Zn alloy joints were investigated. The microstructures of the joints were examined using optical microscope （OM） and scanning transmission electron microscope （STEM）. Vickers hardness test was conducted to evaluate the hardness of the joints. In addition, the relationships between the process parameters, grain size, and hardness of the joints were established. The results show that the developed relationships predict the grain size and hardness of the joints accurately. The Zn content of the alloys is the most effective parameter on the grain size and hardness, where the tool traverse speed has the minimum effect. The relationship between the hardness and grain size of the joints has a deviation from the Hall-Petch equation due to formation of high dislocation density inside the grains. At higher Zn amounts, the dislocation tangles with high density form instead of dislocation cells, and hence, lower conformity with the Hall-Petch relationship is observed.

关键词： Friction stir welding Grain size Hardness Cu-Zn alloy

Photocurrent improvement of an ultra-thin silicon solar cell using the localized surface plasmonic effect of clustering nanoparticles

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Chinese Physics B 2020年第6期29卷 532-537页

作者： F Sobhani H heidarzadeh H Bahador Department of Electrical and Computer Engineering University of Mohaghegh ArdabiliArdabilIran

The cluster-shaped plasmonic nanostructures are used to manage the incident light inside an ultra-thin silicon solar *** we simulate spherical,conical,pyramidal,and cylindrical nanoparticles in a form of a cluster at the rear side of a thin silicon cell,using the finite difference time domain(FDTD)*** calculating the optical absorption and hence the photocurrent,it is shown that the clustering of nanoparticles significantly improves *** photocurrent enhancement is the result of the plasmonic effects of clustering the *** comparison,first a cell with a single nanoparticle at the rear side is *** four smaller nanoparticles are put around it to make a *** photocurrents of 20.478 mA/cm2,23.186 mA/cm2,21.427 mA/cm2,and 21.243 mA/cm2 are obtained for the cells using clustering conical,spherical,pyramidal,cylindrical NPs at the backside,*** values are 13.987 mA/cm2,16.901 mA/cm2,16.507 mA/cm2,17.926 mA/cm2 for the cell with one conical,spherical,pyramidal,cylindrical NPs at the backside,***,clustering can significantly improve the ***,the distribution of the electric field and the generation rate for the proposed structures are calculated.

关键词： clustering nanoparticles plasmonic solar cell localized surface plasmon resonance photocurrent finite difference time domain(FDTD)method light management

Influence of Mould and Insulation Design on Soundness of Tool Steel Ingot by Numerical Simulation

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Journal of Iron and Steel Research(International) 2013年第7期20卷 78-83页

作者： M heidarzadeh H Keshmiri Esfarayen Industrial Complex (EICO) Esfarayen *** North Khorasan Iran

The solidification of 4.4 t cold work tool steel ingot type X210Crl2 was simulated by Magma software. By the reduction of ingot height, solidification modeling and pouring of a new 3 t ingot were performed and decreasing the porosity formation potential in 3 t ingot in comparison with 4.4 t ingot on the basis of Niyama criterion was ob-served which was in good accordance with experimental data. In order to produce sound ingot, a new 2.8 t ingot mould was designed which includes some parameteric changes in mould such as mould slope, slenderness ratio, mould concavity radius, fillet radius of mould internal corners and feeding diameter to ingot upper diameter ratio. Furthermore, the effects of insulating between kokil and feeding ring and also insulating the outer surface of feeding ring as well as insulating the outer surface of one third of kokil upper part on eenterline porosity formation were in-vestigated in both 2.8 and 4.4 t ingots. The results show that the ingot which was produced in new designed 2.8 t mould has a better Niyama pattern and the centerline porosities were eliminated.

关键词： numerical modeling steel ingot mould parameter porosity

Evaluation of the effect of geometrical parameters on stope probability of failure in the open stoping method using numerical modeling

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International Journal of Mining Science and Technology 2019年第3期29卷 399-408页

作者： Shahriyar heidarzadeh Ali Saeidi Alain Rouleau Department of Applied Sciences University of Quebec at Chicoutimi

Stress-induced failure is among the most common causes of instability in Canadian deep underground *** stoping is the most widely practiced underground excavation method in these mines,and creates large stopes which are subjected to stress-induced *** probability of failure(POF)depends on many factors,of which the geometry of an open stope is especially *** this study,a methodology is proposed to assess the effect of stope geometrical parameters on the POF,using numerical *** ranges for each input parameter are defined according to previous surveys on open stope geometry in a number of Canadian underground mines.A Monte-Carlo simulation technique is combined with the finite difference code FLAC3D,to generate model realizations containing stopes with different geometrical *** probability of failure(POF)for different categories of stope geometry,is calculated by considering two modes of failure;relaxation-related gravity driven(tensile)failure and rock mass brittle *** individual and interactive effects of stope geometrical parameters on the POF,are analyzed using a general multi-level factorial ***,mathematical optimization techniques are employed to estimate the most stable stope conditions,by determining the optimal ranges for each stope’s geometrical parameter.

关键词： Stope stability Stope geometrical parameters Probability of failure General factorial design Numerical modeling Sublevel open stoping

Characterization of the tensile properties of friction stir welded aluminum alloy joints based on axial force, traverse speed, and rotational speed

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Frontiers of Mechanical Engineering 2016年第3期11卷 289-298页

作者： Biranchi PANDA A. GARG Zhang JIAN Akbar heidarzadeh Liang GAO IDMEC Instituto Superior Tecnico Universidade de Lisboa Lisboa1040-001 Portugal Department of Mechatronics Engineering Shantou University Shantou515063 China Department of Materials Engineering Azarbaijan Shahid MadaniUniversity Tabriz Iran The State Key Laboratory of Digital Manufacturing Equipment andTechnology Huazahong University of Science and Technology Wuhan430074 China

Friction stir welding （FSW） process has gained attention in recent years because of its advantages over the conventional fusion welding process. These advantages include the absence of heat formation in the affected zone and the absence of large distortion, porosity, oxidation, and cracking. Experimental investigations are necessary to understand the physical behavior that causes the high tensile strength of welded joints of different metals and alloys. Existing literature indicates that tensile properties exhibit strong dependence on the rotational speed, traverse speed, and axial force of the tool that was used. Therefore, this study introduces the experimental procedure for measuring tensile properties, namely, ultimate tensile strength （UTS） and tensile elongation of the welded AA 7020 A1 alloy. Experimental findings suggest that a welded part with high UTS can be achieved at a lower heat input compared with the high heat input condition. A numerical approach based on genetic programming is employed to produce the functional relationships between tensile properties and the three inputs （rotational speed, traverse speed, and axial force） of the FSW process. The formulated models were validated based on the experimental data, using the statistical metrics. The effect of the three inputs on the tensile properties was investigated using 2D and 3D analyses. A high UTS was achieved, including a rotational speed of 1050 r/min and traverse speed of 95 mm/min. The results also indicate that 8 kN axial force should be set prior to the FSW process.

关键词： tensile properties ultimate tensile strength tensile elongation friction stir welding tool rotational speed genetic programming welding speed

Empirical model to predict mass gain of cobalt electroless deposition on ceramic particles using response surface methodology

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Rare Metals 2017年第3期36卷 209-219页

作者： Akbar heidarzadeh Reza Taherzadeh Mousavian Rasoul Azari Khosroshahi Yalda A.Afkham Hesam Pouraliakbar Faculty of Engineering Azarbaijan Shahid Madani UniversityTabriz 7200-000Iran Department of Materials Engineering Sahand University of TechnologyTabriz 65175-4171Iran Department of Advanced Materials WorldTech Scientific Research Center(WT-SRC)Tehran 71857-3834Iran

This investigation was undertaken to predict the mass gain （MG） of cobalt electroless deposition （ED） on ceramic SiC *** surface methodology （RSM） based on a full factorial design with three ED parameters and 30 runs was used to conduct the experiments and to establish a mathematical model by means of Design-Expert *** ED parameters considered were pH,bath temperature and ceramic particle *** of variance was applied to validate the predicted *** results of confirmation analysis by scanning electron microscopy （SEM） show that the developed models are reasonably *** pH is the most effective parameter for the ***,the highest mass gain is obtained for the lowest pH,highest bath temperatures and heat-treated SiC *** addition,the developed model shows that the optimal parameters to get a maximum value of mass gain are pH,bath temperature and ceramic particle state of 8,70 ℃ and heat treatment,respectively.

关键词： Electroless deposition Cobalt SiC particles Mathematical model Response surface method

Regenerative Medicine: A Review of Solutions in the Treatment of Skin Defects

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Open Journal of Regenerative Medicine 2023年第2期12卷 97-113页

作者： Melika heidarzadeh Kaveh Same Fatemeh Baghaie Nia Fatemeh Khavari Sina Shahabi Mohammad Hossein Nabian Saied Reza Mehrpour Mohammadabadi Center for Orthopedic Trans-Disciplinary Applied Research Tehran University of Medical Sciences Tehran Iran

The issue of skin defects is a major concern of almost every trauma surgeon after surgery. Despite numerous conventional methods and introduction of the reconstruction ladder, managing skin defects is still a challenge for the trauma surgeons. In recent years, parallel to the advances in the more conventional methods of skin repair, regenerative medicine has offered new and novel treatments. This article aims to explore these contemporary regenerative solutions as well as to review the conventional methods of treating skin defects.

关键词： Regenerative Medicine Skin Wound Defect