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Article
Publication date: 16 October 2018

Saber Kazeminasab, Alireza Hadi, Khalil Alipour and Mohammad Elahinia

Many people suffer from injuries related to their hand. This research aims to focus on the improvement of the previously developed smart glove by using position and force control…

Abstract

Purpose

Many people suffer from injuries related to their hand. This research aims to focus on the improvement of the previously developed smart glove by using position and force control algorithms. The new smart glove may be used for both physiotherapy and assistance.

Design/methodology/approach

The proposed robot uses shape memory alloy (SMA) actuators coupled to an under-actuated tendon-driven mechanism. The proposed device, which is presented as a wearable glove attached to an actuation module, is capable of exerting extremely high forces to grasp objects in various hand configurations. The device’s performance is studied in physiotherapy and object manipulation tasks. In the physiotherapy mode, hand motion frequency is controlled, whereas the grasping force is controlled in the object manipulation mode. To simulate the proposed system behavior, the kinematic and dynamic equations of the proposed system have been derived.

Findings

The achieved results verify that the system is suitable to be used as part of a rehabilitation device in which it can flex and extend fingers with accurate trajectories and grasp objects efficiently. Specifically, it will be shown that using six SMA wires with the diameter of 0.25 mm, the proposed robot can provide 45 N gripping force for the patients.

Originality/value

The proposed robot uses SMA actuators and an under-actuated tendon-driven mechanism. The resulted robotic system, which is presented as a wearable glove attached to an actuation module, is capable of exerting extremely high force levels to grasp objects in various hand configurations. It is shown that the motion and exerted force of the robot may be controlled effectively in practice.

Details

Industrial Robot: An International Journal, vol. 45 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 17 September 2019

Pouya Panahandeh, Khalil Alipour, Bahram Tarvirdizadeh and Alireza Hadi

Trajectory tracking is a common problem in the field of mobile robots which has attracted a lot of attention in the past two decades. Therefore, besides the search for new…

Abstract

Purpose

Trajectory tracking is a common problem in the field of mobile robots which has attracted a lot of attention in the past two decades. Therefore, besides the search for new controllers to achieve a better performance, improvement and optimization of existing control rules are necessary. Trajectory tracking control laws usually contain constant gains which affect greatly the robot’s performance.

Design/methodology/approach

In this paper, a method based on neural networks is introduced to automatically upgrade the gains of a well-known trajectory tracking controller of wheeled mobile robots. The suggested method speeds up the convergence rate of the main controller.

Findings

Simulations and experiments are performed to assess the ability of the suggested scheme. The obtained results show the effectiveness of the proposed method.

Originality/value

In this paper, a method based on neural networks is introduced to automatically upgrade the gains of a well-known trajectory tracking controller of wheeled mobile robots. The suggested method speeds up the convergence rate of the main controller.

Details

Industrial Robot: the international journal of robotics research and application, vol. 46 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 7 May 2019

Payman Joudzadeh, Alireza Hadi, Bahram Tarvirdizadeh, Danial Borooghani and Khalil Alipour

This paper aims to deal with the development of a novel lower limb exoskeleton to assist disabled people in stair ascending.

Abstract

Purpose

This paper aims to deal with the development of a novel lower limb exoskeleton to assist disabled people in stair ascending.

Design/methodology/approach

For this purpose, a novel design of a mixture of motors and cables has been proposed for users to wear them easily and show the application of the system in stair climbing.

Findings

One of the prominences of this study is the provided robot design where four joints are actuated with only two motors; each motor actuates either the knees or ankles. Another advantage of the designed system is that with motors placed in a backpack, the knee braces can be worn under clothes to be concealed. Finally, the system performance is evaluated using electromyography (EMG) signals showing 28 per cent reduction in energy consumption of related muscles.

Originality/value

This investigation deals with the development of a novel lower limb exoskeleton to assist disabled people in stair ascending.

Details

Industrial Robot: the international journal of robotics research and application, vol. 46 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 4 July 2016

Bahram Tarvirdizadeh, Khalil Alipour and Alireza Hadi

– The purpose of this paper is to focus on an online closed-loop (CL) approach for performing dynamic object manipulation (DOM) by a flexible link manipulator.

Abstract

Purpose

The purpose of this paper is to focus on an online closed-loop (CL) approach for performing dynamic object manipulation (DOM) by a flexible link manipulator.

Design/methodology/approach

Toward above goal, a neural network and optimal control are integrated in a closed-loop structure, to achieve a robust control for online DOM applications. Additionally, an elegant novel numerical solution method will be developed which can handle the split boundary value problem resulted from DOM mission requirements for a wide range of boundary conditions.

Findings

The obtained simulation results reveal the effectiveness of both proposed innovative numerical solution technique and control structure for online object manipulation purposes using flexible manipulators.

Originality/value

The object manipulation problem has previously been studied, however, for the first time its accomplishment by flexible link manipulators was addressed just in offline form considering an open-loop control structure (Tarvirdizadeh and Yousefi-Koma, 2012). As an extension of Tarvirdizadeh and Yousefi-Koma (2012), the current research, consequently, focusses on a numerical solution and a CL approach for performing DOM by a flexible link manipulator.

Details

Engineering Computations, vol. 33 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 23 September 2022

Amir Amjad Mohammadi, Hadi Safaeipour, Mohammad Reza Chenaghlou, Alireza Behnejad and Roham Afghani Khoraskani

This paper aims at discovering the traditional techniques of Persian architecture for covering large-span spaces with a kind of ribbed vault titled “Karbandi”. This structure is…

Abstract

Purpose

This paper aims at discovering the traditional techniques of Persian architecture for covering large-span spaces with a kind of ribbed vault titled “Karbandi”. This structure is generated by intersecting several arches with a harmonic stellar geometry. Preliminary studies show that span factor affects the structural form of karbandi and large-span cases, despite similar architectural forms, have different structural systems and specific construction methods. The main focus of this paper is how karbandi has been designed and built on large-spans. To answer this question, the configuration and construction of a large-span karbandi in Tabriz Bazaar were recognized.

Design/methodology/approach

Data collection of the research was initially done in three parallel directions through the archival study of restoration documents, direct observation of the corpus of the vaultings and interviews with the master mason of the Haj-Mohammad-Qoli Timche restoration team. Then by cross-referencing the gathered data, the construction process of the karbandi was simulated in Rhino 6 and Grasshoppers software and its BIM-M models were created in three levels of development: LOD300, LOD350 and LOD400. In the next step, the preliminary BIM-M models of the karbandi were presented to the interviewed mason and revised and completed based on his comments.

Findings

Analyzing the BIM models by reverse engineering, resulted in (1) Discovering a unique self-supporting masonry construction method applied for the erection of karbandi vaulting on large-spans. (2) Finding the effect of scale factor on the architectural and structural form of the karbandi vault. (3) Discovering the connection types of the karbandi vault based on the construction details.

Originality/value

Despite the wide applications of karbandi vaults throughout history, very little information of their construction techniques is available. The techniques have mostly been experientially and orally passed down from masters to apprentices and rarely been documented. The quest to design and construct a karbandi vault is therefore like solving a puzzle whose most important guide is historical cases. Due to the geometric complexity of karbandi and its ability to cover large-span spaces, solving the puzzle can lead to achieving some technical ideas for masonry cross-ribbed vaulting. A great riddle of the karbandi vaults is how to design and build them on a large span.

Details

Engineering, Construction and Architectural Management, vol. 31 no. 1
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 1 April 2019

Hadi Harati, Fatemeh Nooshinfard, Alireza Isfandyari-Moghaddam, Fahimeh Babalhavaeji and Nadjla Hariri

The purpose of this paper is to identify and design the axial coding pattern of the factors affecting the unplanned use behavior of users of the academic libraries and information…

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Abstract

Purpose

The purpose of this paper is to identify and design the axial coding pattern of the factors affecting the unplanned use behavior of users of the academic libraries and information centers.

Design/methodology/approach

The study as an applied research with a qualitative approach employed the grounded theory. The data collection tool was a deep and semi-structured interview. The interviews data were analyzed and coded during three stages of open, axial and selective coding using the MAXQDA 10 qualitative analysis software. The research population consisted of faculty members and experts in three areas of library and information science, management and psychology. Using the combined targeted sampling method (targeted and then the snowball), 12 subjects were selected as the sample size.

Findings

According to the research findings, the factors affecting the unplanned behavior of users in the use of academic libraries resources and services were identified as factors related to technology, environmental factors, information resources, information services, human resources, individual features, time position factor, cultural factors and social factors. Accordingly, the axial coding pattern of this type of behaviors was designed.

Research limitations/implications

The research limitations include the lack of theoretical basis related to the unplanned behavior issue in the field of library and information science and the lack of full familiarity of most of the experts in the field of library and information science with this topic. These factors lead to the necessity of explaining the subject under discussion.

Originality/value

The unplanned behavior of clients can be utilized to persuade users to use the information resources and library services so that the costs spent on their preparation and collection will be justifiable. The current research addressed this aspect of the unplanned information-seeking behavior.

Details

Aslib Journal of Information Management, vol. 71 no. 2
Type: Research Article
ISSN: 2050-3806

Keywords

Article
Publication date: 24 August 2022

Amir Khiabani, Alireza Rashidi Komijan, Vahidreza Ghezavati and Hadi Mohammadi Bidhandi

Airline scheduling is an extremely complex process. Moreover, disruption in a single flight may damage the entire schedule tremendously. Using an efficient recovery scheduling…

Abstract

Purpose

Airline scheduling is an extremely complex process. Moreover, disruption in a single flight may damage the entire schedule tremendously. Using an efficient recovery scheduling strategy is vital for a commercial airline. The purpose of this paper is to present an integrated aircraft and crew recovery plans to reduce delay and prevent delay propagation on airline schedule with the minimum cost.

Design/methodology/approach

A mixed-integer linear programming model is proposed to formulate an integrated aircraft and crew recovery problem. The main contribution of the model is that recovery model is formulated based on individual flight legs instead of strings. This leads to a more accurate schedule and better solution. Also, some important issues such as crew swapping, reassignment of aircraft to other flights as well as ground and sit time requirements are considered in the model. Benders’ decomposition approach is used to solve the proposed model.

Findings

The model performance is also tested by a case including 227 flights, 64 crew, 56 aircraft and 40 different airports from American Airlines data for a 24-h horizon. The solution achieved the minimum cost value in 35 min. The results show that the model has a great performance to recover the entire schedule when disruption happens for random flights and propagation delay is successfully limited.

Originality/value

The authors confirm that this is an original paper and has not been published or under consideration in any other journal.

Details

Journal of Modelling in Management, vol. 18 no. 6
Type: Research Article
ISSN: 1746-5664

Keywords

Article
Publication date: 9 May 2020

Aziz Homayouni, Reza Rezaei Mokarram, Sharareh Norouzi, Alireza Dehnad, Ali Barkhordari, Hamideh Homayouni and Hadi Pourjafar

Among soy products, soy ice cream with neutral pH, high total solids contents and prebiotic oligosaccharides is an appropriate vehicle for probiotics. The purpose of this paper is…

Abstract

Purpose

Among soy products, soy ice cream with neutral pH, high total solids contents and prebiotic oligosaccharides is an appropriate vehicle for probiotics. The purpose of this paper is to survey soy ice cream as a carrier for the efficient delivering of Lactobacillus casei, or L. casei.

Design/methodology/approach

Probiotic soy ice cream containing L. casei was produced via the powder of soy milk. The physicochemical and organoleptic properties of the product were assessed. Also, the viability of L. casei was surveyed over a 180-day period of storage at −25 °C.

Findings

The density characteristic of probiotic soy ice cream demonstrated a significant rise (P < 0.05). The result of the viability analysis showed significant alterations in the number of probiotics in this product after freezing and throughout the 180-day period (P < 0.05). The most noticeable drop was seen throughout the first 60 days about 1.83 logs after that the trend of survival of this probiotic strain leveled off over the next 120 days. Also, no significant differences were found in the organoleptic properties of both ice creams.

Originality/value

Soy ice cream with prebiotic elements protected the growing and activity of probiotic bacteria. The results showed that L. casei is a good probiotic for soy ice cream.

Details

Nutrition & Food Science , vol. 51 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 28 October 2013

Sady Tavakoli, D.D. Ganji, Alireza Rasekh, Babak Haghighi and Hadi Jahani

– This work aims to focus on the study of natural convection heat transfer characteristics in a vertical wall embedded in a non-Darcy porous medium filled with nanofluids.

Abstract

Purpose

This work aims to focus on the study of natural convection heat transfer characteristics in a vertical wall embedded in a non-Darcy porous medium filled with nanofluids.

Design/methodology/approach

The governed partial differential equations are transformed into ordinary differential equations which are obtained by similarity solution and then have been solved through homotopy analysis method.

Findings

The results show that Cu-water as nanofluid enhances the local Nusselt number more than other nanofluids.

Originality/value

Nanoparticles and nanofluid enhance the local Nusselt number.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 23 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 14 December 2023

Yasaman Zibaei Vishghaei, Sohrab Kordrostami, Alireza Amirteimoori and Soheil Shokri

Assessing inputs and outputs is a significant aspect of taking decisions while there are complex and multistage processes in many examinations. Due to the presence of interval…

Abstract

Purpose

Assessing inputs and outputs is a significant aspect of taking decisions while there are complex and multistage processes in many examinations. Due to the presence of interval performance measures in various real-world studies, the purpose of this study is to address the changes of interval inputs of two-stage processes for the perturbations of interval outputs of two-stage systems, given that the overall efficiency scores are maintained.

Design/methodology/approach

Actually, an interval inverse two-stage data envelopment analysis (DEA) model is proposed to plan resources. To illustrate, an interval two-stage network DEA model with external interval inputs and outputs and also its inverse problem are suggested to estimate the upper and lower bounds of the entire efficiency and the stages efficiency along with the variations of interval inputs.

Findings

An example from the literature and a real case study of the banking industry are applied to demonstrate the introduced approach. The results show the proposed approach is suitable to estimate the resources of two-stage systems when interval measures are presented.

Originality/value

To the best of the authors’ knowledge, there is no study to estimate the fluctuation of imprecise inputs related to network structures for the changes of imprecise outputs while the interval efficiency of network processes is maintained. Accordingly, this paper considers the resource planning problem when there are imprecise and interval measures in two-stage networks.

Details

Journal of Modelling in Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1746-5664

Keywords

1 – 10 of 19