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      • KCI등재

        The effects of water-pipe smoking on birth weight: a population-based prospective cohort study in southern Iran

        Shahrzad Nematollahi1,,Mohammad Ali Mansournia,Abbas Rahimi Foroushani,Mahmood Mahmoodi,Azin Alavi,Mohammad Shekari,Kourosh Holakouie-Naieni 한국역학회 2018 Epidemiology and Health Vol.40 No.-

        OBJECTIVES: Consecutive community health assessments revealed that water-pipe smoking in women and impaired growth in children were among the main health concerns in suburban communities in southern Iran. The aim of the present study was to identify the effects of water-pipe smoking during pregnancy on birth weight. METHODS: Data from a population-based prospective cohort study of 714 singleton live pregnancies in the suburbs of Bandar Abbas in southern Iran in 2016-2018 were used in this study. Data about water-pipe smoking patterns and birth weight were collected by questionnaires during and after the pregnancy. Low birth weight (LBW) was defined as a birth weight below 2,500 g. Statistical analyses were performed using generalized linear models, and the results were presented in terms of relative risk (RR) and 95% confidence intervals (CI). RESULTS: Fifty (8.2%) of the study subjects smoked water-pipe. The adjusted risk of LBW increased 2-fold in water-pipe smokers (adjusted RR [aRR], 2.09; 95% CI, 1.18 to 3.71), and by 2.0% for each 1-year increase in the duration of water-pipe smoking (aRR, 1.02; 95% CI, 0.99 to 1.05). CONCLUSIONS: Our results showed that water-pipe smoking during pregnancy was an important risk factor for LBW in this population sample from southern Iran. The introduction of regulations onto prevent water-pipe smoking and the implementation of community health action plans aiming at empowering women and increasing women’s knowledge and awareness regarding the health consequences of water-pipe smoking are proposed.

      • SCIEKCI등재

        Phylogenetic Analysis of New Isolates of Cucumber mosaic virus from Iran on the Basis of Different Genomic Regions

        Nematollahi, Sevil,Sokhandan-Bashir, Nemat,Rakhshandehroo, Farshad,Zamanizadeh, Hamid Reza The Korean Society of Plant Pathology 2012 Plant Pathology Journal Vol.28 No.4

        Molecular characterization of Cucumber mosaic virus (CMV) was done by using samples from tomato and cucurbitaceous plants collected from different locations in the northwest region of Iran. After screening by enzyme-linked immunosorbent assay, 91 CMV-infected samples were identified. Biological properties of eight representative isolates were compared with each other revealing two distinct phenotypes on squash and tomato plants. Phylogenetic analyses based on nucleotide sequences of the coat protein (CP), movement protein (MP) and 2b of the new isolates, together with that of previously reported isolates, led to the placement of the Iranian isolates in subgroups IA and IB according to CP and MP genes, but in subgroup IA according to the 2b gene. These data suggest that reassortment may have been a major event in the evolution of CMV in Iran, and that the Iranian isolates are derived from a common recent ancestor that had passed through a bottleneck event.

      • SCIESCOPUS

        Experimental study of the effect of brazed compact metal-foam evaporator in an organic Rankine cycle performance: Toward a compact ORC

        Nematollahi, Omid,Abadi, Gholamreza Bamorovat,Kim, Dae Yeon,Kim, Kyung Chun Elsevier 2018 Energy conversion and management Vol.173 No.-

        <P><B>Abstract</B></P> <P>Compact-sized organic Rankine cycle (ORC) power generators require small-scale heat exchangers to achieve high power density. The objective of this study is to investigate the effect of a Brazed Metal-foam Plate Heat Exchanger (BMPHE) in an Organic Rankine Cycle (ORC) performance parameters. This evaporator is one of the first industrial full BMPHE which is composed by Nickle-foam with 25 PPI (pore per inch). In addition, a series of the experiments have been done using conventional Brazed Plate Heat Exchanger (BPHE) to make a comprehensive comparison for both cycles. Two parameters of power density and pressure gradient are introduced to make a clear comparison in addition to ORC performance parameters. Experimental data are presented for a 1-kW scroll expander and heat source temperatures between 80 and 120 °C. The results show that although the compact evaporator (BMPHE) increases the pressure drop by factors of 1.4–2.6, the overall performance of the ORC is not adversely affected, and the power density is increased by a factor of 2.5 in maximum.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel application of compact Brazed Metal-foam Plate Heat Exchanger is presented. </LI> <LI> The introduced heat exchanger is tested in an organic Rankine cycle to emphasize the size effect. </LI> <LI> The power density and pressure gradient is used for the comparison. </LI> <LI> The power density is increased by a factor of 2.5 in maximum. </LI> </UL> </P>

      • A feasibility study of solar energy in South Korea

        Nematollahi, Omid,Kim, Kyung Chun Elsevier 2017 RENEWABLE & SUSTAINABLE ENERGY REVIEWS Vol.77 No.-

        <P><B>Abstract</B></P> <P>Through the years using renewable energies become one of the interesting issues in each country. Among the renewable energies, solar energy is more attractive. Governments planned to install more solar power plants. Feasibility study is an important step of every solar energy project. This paper investigates the feasibility of using solar energy in different regions of South Korea. For this purpose, the maximum, minimum, and average values of yearly horizontal radiation were calculated for 24 stations for a five-year period. Monthly and annual clearness indices for these stations were then calculated. The annual average horizontal radiation map and Geographic Information Systems (GIS) maps of global horizontal radiation were prepared for each month of the year. Maps were then prepared for the annual average of monthly mean clearness index for the 24 stations. Furthermore, the sunshine hours were presented for 78 stations for a three-year period. The results show that the central and southern regions of South Korea receive higher quantities of horizontal radiation, but not the northern areas.</P>

      • SCIESCOPUS

        An evaluation of wind turbine waste heat recovery using organic Rankine cycle

        Nematollahi, Omid,Hajabdollahi, Zahra,Hoghooghi, Hadi,Kim, Kyung Chun Elsevier 2019 JOURNAL OF CLEANER PRODUCTION Vol.214 No.-

        <P><B>Abstract</B></P> <P>Wind turbine size has increased to megawatt capacity, and the related technologies and facilities have improved, including the cooling systems. Currently, all of the heat generated by wind turbine components is wasted to the environment. This study presents a conceptual design of a novel method for waste heat recovery of a wind turbine using an organic Rankine cycle (ORC). An organic Rankine cycle is implemented to the wind turbine as a part of the cooling system. The proposed system is thermodynamically modeled to evaluate the amount of recovered energy. Seven working fluids are chosen and investigated in the simulations to estimate the working fluid effect. The results revealed that the organic Rankine cycle can be a suitable choice for cooling wind turbines while simultaneously produce the power. Both exergy and energy analysis are conducted. A maximum power of 7.1 kW is provided by the proposed system using R134 when 20 K superheat is utilized. While R600a and SE36 stand on the next place. Furthermore, a minimum of 6.25 kW power is achievable. The generated work can be used as pump driving or electricity generation. In the next step, the thermal efficiency and total annual cost are optimized simultaneously using a multi-objective optimization for R134a as best working fluid in the thermodynamic viewpoint. It is found that the ideal efficiency of the system is obtained to be 14.7% with the total price of 7050 $/year. Finally, the effects of design parameters on the efficiency are obtained.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel method for wind turbine cooling using organic Rankine cycles is proposed. </LI> <LI> The proposed method can produce power while is cooling the wind turbine. </LI> <LI> ORC is modeled in both energy and exergy approach with different working fluids. </LI> <LI> A multi-objective optimization is applied for economical evaluation. </LI> <LI> A 7.1 kW power is utilized through the wind turbine cooling using R134. </LI> </UL> </P>

      • KCI등재

        The influence of cubic real-gas equations of state in the supersonic regime of dense gases

        Omid Nematollahi,Mahdi Nili-Ahmadabadi,김경천 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.4

        Real-gas effects should be considered in ORC expanders, particularly in a supersonic flow. This study deals with the numerical evaluation of cubic real gas models in a supersonic R245fa flow over a wedge-shaped cascade. The NIST Refprop real gas model was selected as a benchmark model, and four other cubic real gas equations of state (EoS) were evaluated with respect to the reference model. The four cubic real gas EoS are studied. The results show that the Peng-Robison EoS is the most accurate model with an average error of less than 1.1 % for Mach number prediction for 3 different sections, and its computational cost is 39 % lower than NIST. However, the Aungier-Redlich-Kwong EoS model shows better performance accuracy and the computational cost with an average error of 1.7 % for Mach number prediction and a 17 % computational cost lower than NIST. Therefore, using this model is recommended for modeling R245fa in the supersonic regime.

      • KCI등재
      • KCI등재

        Structural Behavior of Precast Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) Cantilever Retaining Walls: Part I - Analysis and Design Procedures and Environmental Impact Calculations (EIC)

        Behzad Nematollahi,Yen Lei Voo,Raizal Saifulnaz M. R. 대한토목학회 2014 KSCE JOURNAL OF CIVIL ENGINEERING Vol.18 No.5

        Ultra-high Performance Fiber Reinforced Concrete (UHPFRC) is a new generation of cementitious based construction materialdeveloped in the mid 1990s that its unique characteristics such as high durability and impermeability, negligible shrinkage/creep andhigh impact resistance lead to almost maintenance free and direct enhancement of the life-span of a structure. UHPFRC is an ecofriendlyand environmentally green construction material which has the capacity to compete not only with conventional ReinforcedConcrete (RC) or prestressed concrete design, but it is also able to compete with conventional steel design. This paper is presented intwo parts. The first part (Part I) of this paper presents the analysis and design procedures of the precast UHPFRC cantilever retainingwalls as a sustainable alternative approach to conventional precast RC cantilever retaining walls. Further, the Environmental ImpactCalculations (EIC) of the precast UHPFRC cantilever retaining walls were compared against the conventional precast RC cantileverretaining walls as the benchmark. The second part (Part II) of this paper evaluates the reliability of the precast UHPFRC cantileverretaining walls through experimental tests on full scale UHPFRC wall specimens. The EIC results proved that cantilever retainingwalls fabricated from UHPFRC are generally more environmentally sustainable than those built of the conventional RC with respectto the reduction of CO2 emissions, Embodied Energy (EE) and Global Warming Potential (GWP). Finally, advantages of the precastUHPFRC cantilever retaining walls versus the conventional precast RC walls were presented.

      • KCI등재

        Phylogenetic Analysis of New Isolates of Cucumber mosaic virus from Iran on the Basis of Different Genomic Regions

        Sevil Nematollahi,Nemat Sokhandan-Bashir,Farshad Rakhshandehroo,Hamid Reza Zamanizadeh 한국식물병리학회 2012 Plant Pathology Journal Vol.28 No.4

        Molecular characterization of Cucumber mosaic virus (CMV) was done by using samples from tomato and cucurbitaceous plants collected from different locations in the northwest region of Iran. After screening by enzyme-linked immunosorbent assay, 91 CMV-infected samples were identified. Biological properties of eight representative isolates were compared with each other revealing two distinct phenotypes on squash and tomato plants. Phylogenetic analyses based on nucleotide sequences of the coat protein (CP), movement protein (MP) and 2b of the new isolates, together with that of previously reported isolates, led to the placement of the Iranian isolates in subgroups IA and IB according to CP and MP genes, but in subgroup IA according to the 2b gene. These data suggest that reassortment may have been a major event in the evolution of CMV in Iran, and that the Iranian isolates are derived from a common recent ancestor that had passed through a bottleneck event.

      • KCI등재

        Experimental and Numerical Study of the Critical Length of Short Kenaf Fiber Reinforced Polypropylene Composites

        Mohammad Nematollahi,Mehdi Karevan,Marzieh Fallah,Mahmoud Farzin 한국섬유공학회 2020 Fibers and polymers Vol.21 No.4

        Widespread attention to make use of biodegradable resources as a replacement for petroleum products leads to theexploitation of natural fiber reinforced composites. Natural fiber reinforced polymer composites usually exhibit lowermechanical properties than synthetic fiber ones. Thus, understanding key factors affecting the overall mechanical propertiesin order to increase them is crucial. One underlying factor is the length of fiber highly contributing to the extent of matrix/fiber interfacial load transfer at the interface. However, the concurrent examination of the load transfer mechanism at theinterface of fiber/matrix in terms of fiber length has not been well performed using computational, analytical andexperimental approaches. This work is aimed at the determination of the critical fiber length associated with a full loadtransfer condition using various methods to better understand their accuracy and the interfacial load transfer mechanism. Forthis purpose, specimens of neat polypropylene (PP) and 20 wt% kenaf/PP composites were fabricated using extrusioninjection molding. Tensile testing, scanning electron microscopy and density measurements were conducted to incorporatethe obtained results into the models and to verify the results predicted by the models. A three dimensional representativevolume element (RVE) representing the filler content of fabricated specimens was assumed. A micromechanical model wasemployed to make the results of analysis independent of the RVE dimensions. The critical fiber length for a full load transferwas determined by evaluating the stored elastic strain energy changes against the fiber length. The results showed that thekenaf fiber length is critical to both the load transfer efficiency and stiffening of composites. The results further revealed thatto obtain the full interfacial load transfer, the length of kenaf fibers needs to be greater than the critical length being ~2.4 mmprovided that perfect kenaf/PP interfacial interaction exists.

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