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Article
Publication date: 5 August 2019

Payam Asadi and Hosein Sourani

In the absence of random variables, random variables are generated by the Monte Carlo (MC) simulation method. There are some methods for generating fragility curves with fewer…

134

Abstract

Purpose

In the absence of random variables, random variables are generated by the Monte Carlo (MC) simulation method. There are some methods for generating fragility curves with fewer nonlinear analyses. However, the accuracy of these methods is not suitable for all performance levels and peak ground acceleration (PGA) range. This paper aims to present a method through the seismic improvement of the high-dimensional model representation method for generating fragility curves while taking advantage of fewer analyses by choosing the right border points.

Design/methodology/approach

In this method, the values of uncertain variables are selected based on the results of the initial analyses, the damage limit of each performance level or according to acceptable limits in the design code. In particular, PGAs are selected based on the general shape of the fragility curve for each performance limit. Also, polynomial response functions are estimated for each accelerogram. To evaluate the accuracy, fragility curves are estimated by different methods for a single degree of freedom system and a reinforced concrete frame.

Findings

The results indicated that the proposed method can not only reduce the computational cost but also has a higher accuracy than the other methods, compared with the MC baseline method.

Originality/value

The proposed response functions are more consistent with the actual values and are also congruent with each performance level to increase the accuracy of the fragility curves.

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Article
Publication date: 8 August 2017

Iman Asadi, Norhayati Mahyuddin and Payam Shafigh

The purpose of this paper is to review the concept of occupant behavior and its relation with indoor environmental quality (IEQ) and building energy consumption. The behavior is…

1698

Abstract

Purpose

The purpose of this paper is to review the concept of occupant behavior and its relation with indoor environmental quality (IEQ) and building energy consumption. The behavior is referred to any direct or indirect action, which is selected by an occupant to manage the unpleasant indoor environmental conditions. Thermal comfort, indoor air quality, aural comfort and visual comfort are the key factors of IEQ evaluation. Human behavior significantly interacts with energy consumption in buildings.

Design/methodology/approach

Each IEQ parameter was reviewed separately and the overall IEQ acceptance was considered. In addition, this paper reviews the methods that were used to measure and simulate the IEQ factors, energy consumption and human behavior. Finally, the lack of knowledge in this field is based on the review demonstrated.

Findings

Most studies considered one or two IEQ factors to evaluate IEQ acceptance in buildings. Further, weakness of simulating all IEQ factors at the same time is the deficiency of IEQ simulation, based on reviews. In the case of occupant behavior simulation, the uncertainly of human psychological parameter is a drawback to predict behavior.

Originality/value

Energy consumption, occupant health and productivity are related to IEQ. Human behavior affects building energy consumption directly. Simulation software and methods can predict IEQ factors and human behavior. Therefore, reviewing the existing studies is critical to find new methods for measuring and simulating IEQ, energy consumption and human behavior in buildings.

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Article
Publication date: 22 March 2024

Mohammad Dehghan Afifi, Bahram Jalili, Amirmohammad Mirzaei, Payam Jalili and Davood Ganji

This study aims to analyze the two-dimensional ferrofluid flow in porous media. The effects of changes in parameters such as permeability parameter, buoyancy parameter, Reynolds…

81

Abstract

Purpose

This study aims to analyze the two-dimensional ferrofluid flow in porous media. The effects of changes in parameters such as permeability parameter, buoyancy parameter, Reynolds and Prandtl numbers, radiation parameter, velocity slip parameter, energy dissipation parameter and viscosity parameter on the velocity and temperature profile are displayed numerically and graphically.

Design/methodology/approach

By using simplification, nonlinear differential equations are converted into ordinary nonlinear equations. Modeling is done in the Cartesian coordinate system. The finite element method (FEM) and the Akbari-Ganji method (AGM) are used to solve the present problem. The finite element model determines each parameter’s effect on the fluid’s velocity and temperature.

Findings

The results show that if the viscosity parameter increases, the temperature of the fluid increases, but the velocity of the fluid decreases. As can be seen in the figures, by increasing the permeability parameter, a reduction in velocity and an enhancement in fluid temperature are observed. When the Reynolds number increases, an increase in fluid velocity and temperature is observed. If the speed slip parameter increases, the speed decreases, and as the energy dissipation parameter increases, the temperature also increases.

Originality/value

When considering factors like thermal conductivity and variable viscosity in this context, they can significantly impact velocity slippage conditions. The primary objective of the present study is to assess the influence of thermal conductivity parameters and variable viscosity within a porous medium on ferrofluid behavior. This particular flow configuration is chosen due to the essential role of ferrofluids and their extensive use in engineering, industry and medicine.

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Article
Publication date: 16 November 2010

Hamid R. Jamali, Fatemeh Nooshinfard, Golizeh Baghestani and Saeid Asadi

This paper aims to evaluate the use and the costs of AMIN, the interlibrary loan service in Iran.

489

Abstract

Purpose

This paper aims to evaluate the use and the costs of AMIN, the interlibrary loan service in Iran.

Design/methodology/approach

A questionnaire was used for the data collection. It was completed by those librarians in charge of AMIN in academic libraries.

Findings

The statistics collected from six libraries showed that 514 items were loaned, of which 49 per cent were journal articles and 43 per cent were books. Post was used for the delivery of about 55 per cent of the items, while e‐mail was used for the delivery of only 7 per cent of the items. The average time spent dealing with each request (the time lapse between receipt of the request and dispatching the item) was about 7.1 days. The library of the University of Tehran was the most effective library in this regard as it only took 3.4 days on average for each request. The study revealed that the participating libraries did not have a proper procedure in place for collecting usage statistics and therefore one cannot evaluate the effectiveness of the AMIN service.

Originality/value

The paper reveals the cost of document supply in Iranian academic libraries and illustrates that ILL services in Iran are not efficient and that measures could be taken to reduce the cost and increase the efficiency of services.

Details

Interlending & Document Supply, vol. 38 no. 4
Type: Research Article
ISSN: 0264-1615

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Article
Publication date: 1 December 2017

Amirreza Farahbod and Uğur Dağli

From an architectonic point of view, the identity of Iranian houses has become more enriched itself throughout history. Primarily, during the Qajardynasty (1785-1925)as a…

42

Abstract

From an architectonic point of view, the identity of Iranian houses has become more enriched itself throughout history. Primarily, during the Qajardynasty (1785-1925)as a consequence of the social, political, and economical changes which took place, there was a turning point from traditional architectural construction to the modernism principals of construction. In this regard, this studyaims toexplore the importance of the compatibility of the termidentity of architecture in the transformation age (a period which led tothe turning point in the history of Iranian architecture) bydescriptive (including comparative and co-relational methods) and explanative-analytical methods.

By evaluating the spatial characteristics of TraditionalIranian Houses (TIH), the study has developed a method of assessingthe architectural identity of the Qajar era. It alsointroduceda Top-down and Bottom-up processing method as the two main factors in shapingthe identityofan architectural style. By comparing both the objective and subjective indicators of shapingthe identity of TIH, the study also revealed that, in transitioning from the traditional construction to modern, the physical characteristics of the houses might change considerably, whilst lifestyles will not change at the same speed.

Details

Open House International, vol. 42 no. 4
Type: Research Article
ISSN: 0168-2601

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Article
Publication date: 30 October 2024

Ali Ahmadi Azar, Payam Jalili, Bahram Jalili and D.D. Ganji

This study examines fluid flow within a rectangular porous medium bounded by walls capable of expansion or contraction. It focuses on a non-Newtonian fluid with Casson…

20

Abstract

Purpose

This study examines fluid flow within a rectangular porous medium bounded by walls capable of expansion or contraction. It focuses on a non-Newtonian fluid with Casson characteristics, incompressibility, and electrical conductivity, demonstrating temperature-dependent impacts on viscosity.

Design/methodology/approach

The flow is two-dimensional, unsteady, and laminar, influenced by a small electromagnetic force and electrical conductivity. The Hybrid Analytical and Numerical Method (HAN method) resolves the constitutive differential equations.

Findings

The fluid’s velocity is influenced by the Casson parameter, viscosity variation parameter, and resistive force, while the fluid’s temperature is affected by the radiation parameter, Prandtl number, and power-law index. Increasing the Casson parameter from 0.1 to 50 results in a 4.699% increase in maximum fluid velocity and a 0.123% increase in average velocity. Viscosity variation from 0 to 15 decreases average velocity by 1.42%. Wall expansion (a from −4 to 4) increases maximum velocity by 19.07% and average velocity by 1.09%. The average fluid temperature increases by 100.92% with wall expansion and decreases by 51.47% with a Prandtl number change from 0 to 7.

Originality/value

Understanding fluid dynamics in various environments is crucial for engineering and natural systems. This research emphasizes the critical role of wall movements in fluid dynamics and offers valuable insights for designing systems requiring fluid flow and heat transfer. The study presents new findings on heat transfer and fluid flow in a rectangular channel with two parallel, porous walls capable of expansion and contraction, which have not been previously reported.

Details

Multidiscipline Modeling in Materials and Structures, vol. 21 no. 1
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 21 February 2020

Payam Farhadi and Seyed Masoud Moghaddas Tafreshi

The use of power sectionalizers in electric power distribution networks as disconnecting devices for optimum network configuration is indispensable. Major reasons to use…

81

Abstract

Purpose

The use of power sectionalizers in electric power distribution networks as disconnecting devices for optimum network configuration is indispensable. Major reasons to use sectionalizers, here manual sectionalizers, is their lower installation and operating prices compared to other types of disconnecting devices and that most of conventional realistic electric power distribution systems are still using manual sectionalizers due to their ease of procurement. However, in case of failure for these switches, power supply interruptions are unavoidable unless optimum solutions are used for configuration (and possibly reconfiguration) of sectionalizers. Thus, in this research, binary exchange market algorithm (BEMA) as a novel evolutionary metaheuristic is used to meet the maximized customer satisfaction by optimized configuration of sectionalizers within electric power distribution networks in the presence of distributed generations (DGs). To solve the problem, BEMA is used on sectionalizing switch placement problem, which has only two open and close (0/1) states. A novel multi-objective optimization problem has been formulated as a function of two aspects, namely, improved reliability index (for customer benefit) and minimized sectionalizing switch costs (for utility benefits). Simulations are carried out in three different case studies to validate the effectiveness of the BEMA both in theory and practice: Standard IEEE 33-bus test system, practical feeder-8 of MeshkinShahr Town’s electric power distribution network in northwest of Iran; and Roy Billinton test system Bus 4 (RBTS-Bus 4). The obtained results are compared with those of the previously validated ant colony optimization (ACO) technique in RBTS-Bus 4.

Design/methodology/approach

The optimum configuration of sectionalizers in the presence of DGs has been formulated as a multi-objective function consisting of two conflicting objectives. First objective is to improve the power distribution network reliability indices. Second objective is to fulfill the first objective with a minimized sectionalizing switch cost. The latter is probably obtained by reducing the number of installed sectionalizers. The obtained results by BEMA have been compared with those of ACO technique.

Findings

In this paper, optimal configuration of sectionalizers has been performed based on a multiobjective function by binary exchange market algorithm. By simulations carried out on two standards and one practical test systems, the proposed algorithm effectiveness was confirmed and the obtained results were compared to ACO algorithm. Changing weighting factors shows that better satisfaction can be obtained when difference between the weighting factors is relatively greater. In other words, the reliability membership function is more than switch cost membership, and thus, if the values of two weighting factors are close enough, the satisfaction level reduces. The number of installed sectionalizing switches by BEMA and ACO techniques in different scenarios were performed.

Originality/value

Proposal of a novel multi-objective function for finding optimal location of sectionalizers in the presence of DGs with binary exchange market algorithm whose merit over the other heuristics is to consider all the problem specifications only in one multi-objective function. Despite previously reported works that have used various high-priced protective devices for achieving the enhanced reliability this research only utilizes inexpensive manual sectionalizers with the least possible cost in the presence of DGs. Two standard test cases IEEE 33-bus test system and RBTS-Bus 4 and one realistic test case feeder-8 of MeshkinShahr Town power distribution network in northwest of Iran are used to demonstrate the effectiveness of the proposed technique in theory and real-world applications. Thus, utilities may take the advantage of the proposed method for configuration of sectionalizers in their own local power distribution systems throughout the country.

Available. Open Access. Open Access
Article
Publication date: 22 September 2021

Ehsan Sorooshnia, Maria Rashidi, Payam Rahnamayiezekavat, Fatemeh Rezaei and Bijan Samali

Optimisation of daylight admission through window is crucial for alleviating glare while maintaining useful daylight levels in order to enhance occupants' health, visual comfort…

2898

Abstract

Purpose

Optimisation of daylight admission through window is crucial for alleviating glare while maintaining useful daylight levels in order to enhance occupants' health, visual comfort and moderating lighting energy consumption. Amongst various solutions, fixed external shade is an affordable solution for housing spaces that need to be sophisticatedly designed, especially during the period of increasing home spaces as working environments. In the humid subtropical region, daylight control plays an important role in indoor comfort, particularly with areas with a high window to wall ratio (WWR). Due to the insufficient amount of such study on non-office spaces in Australia, shading-related standards are not addressed in Australian building codes.

Design/methodology/approach

The chosen methodology for the research is a quantitative data collection and analysis through field measurement and simulation simultaneously. The first step is a multi-objective optimisation of shading elements through a non-dominated sorting genetic algorithm (NSGA-II) on parametric modelling via Rhino3D CAD and simulation engines (DIVA and ClimateStudio). In the second phase, the Pareto front solutions are validated by experimental measurements within a room with a single north-facing window (the most probable for the daytime glare in Sydney) for the seven most common local window configurations.

Findings

Through the simulation of ten genes, 1,560 values and 2.4 × 1,019 of search space, this study found an optimum shade for each local common window layout, resulted in +22% in (UDI) and −16% in views with discomfort glare on average. Moreover, an all-purpose polygonal shade showed an average of 4.6% increase in UDI and a 5.83% decrease in the percentage of views with discomfort glare.

Research limitations/implications

The findings are subject to the room dimensions, window dimensions and layouts, and orientation of windows for selected residential buildings in Sydney.

Originality/value

The study contributes to the development of highly accurate fixed external shading systems with rectangular and tapered-form external shapes. A real-time measurement by luminance-metre sensors and HQ cameras located at six eye levels is conducted to corroborate simulation results of the visual comfort.

Details

Engineering, Construction and Architectural Management, vol. 30 no. 1
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 9 May 2016

Lida Kakia, Habil Nikolay Popov and Abbas Madandar Arani

The paper describes the relationship between parents’ and teachers’ demographic factors and their judgments about children’s activities and school readiness in primary schools of…

557

Abstract

Purpose

The paper describes the relationship between parents’ and teachers’ demographic factors and their judgments about children’s activities and school readiness in primary schools of Tehran. The purpose of this paper is to determine: first, the relationship between the child’s gender and the frequency of parent-child activities; second, the relationship between the parent’s gender, age and educational level and the frequency of parent-child activities; and third, the relationship between the teacher’s gender, educational level and length of service with rate of frequency of the child’s school readiness.

Design/methodology/approach

Multi-stage Cluster Sampling was used to select samples, and the research instruments (questionnaires) were distributed among 36 first grade teachers and 756 parents.

Findings

The study found that there were significant gender differences in hands-on activities. With regards to the parent’s age and gender, there were significant differences only in hands-on activities, while, with respect to the educational level of fathers and mothers, there were significant differences in both hands-on and community activities among children. Finally, the finding indicated that there was a significant relationship between children’s skills and the teacher’s gender and length of service.

Originality/value

Although the research findings are consistent with the reality of Iranian families, more research is needed relating the types of activities in which parents and children engage.

Details

International Journal of Comparative Education and Development, vol. 18 no. 2
Type: Research Article
ISSN: 2396-7404

Keywords

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Article
Publication date: 5 October 2015

Mousa Yaminfirooz, Fatemeh Nooshinfard and Hasan Siamian

The purpose of this paper is to evaluate the status of organizational climate of Iranian academic libraries and map its structural equation model. Organizational climate is one of…

727

Abstract

Purpose

The purpose of this paper is to evaluate the status of organizational climate of Iranian academic libraries and map its structural equation model. Organizational climate is one of the main indicators of organizational health and dynamic.

Design/methodology/approach

This research was an applied survey. The statistical population of the research included all staff working in 96 central libraries of Iranian governmental universities (N = 520). A self-administered questionnaire was used for data collection. Some descriptive and inferential statistical methods applied for data analysis in SPSS and factor analysis in LISREL software were used for modelling organizational climates in the libraries.

Findings

The t values of factor analysis pass showed that the effect of all indicators of ClimateQUAL on organizational climate was significant. The factor loading of the pass model showed that among the nine indicators, climate for psychological safety with 5.24, climate for innovation with 5.06 and climate for leadership with 4.93 had a higher effect on organizational climate of the libraries. Considering the values of goodness-of-fit indicators, the path model has an optimal status in all indicators, but that of RMSEA in which the status is relatively acceptable. The observed data relatively matched the theoretical model.

Originality/value

The t values of factor analysis pass showed that the effect of all indicators of ClimateQUAL on organizational climate was significant. The factor loading of the pass model showed that among the nine indicators, climate for psychological security with 5.24, climate for innovation with 5.06 and climate for leadership with 4.93 had a higher effect on organizational climate of the libraries. Considering the values of goodness-of-fit indicators, the path model has an optimal status in all indicators, except the RMSEA in which the status is relatively acceptable. The observed data relatively matched the theoretical model.

Details

The Electronic Library, vol. 33 no. 5
Type: Research Article
ISSN: 0264-0473

Keywords

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