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Article
Publication date: 20 April 2020

Ananthan Nagarajan, Sivachandran P., Suganyadevi M.V. and Muthukumar P.

The purpose of this study is to help the researchers, public, industries and government to realize the tremendous trends to improve the power quality of both sources and load side.

Abstract

Purpose

The purpose of this study is to help the researchers, public, industries and government to realize the tremendous trends to improve the power quality of both sources and load side.

Design/methodology/approach

The work carried out in the Facts device and power quality issues.

Findings

Maintaining the quality of electric power is always a challenging task. The effect of power electronics devices leads to improper power quality. The use of FACTS devices is preferably the best approach to treat power-quality-related problems. Usually, all FACTS devices are constructed to operate on the side of either the source side or the load.

Originality/value

This paper explores a broad comprehensive study of various types of power quality problems and classification of FACTS devices with its recent developments. Furthermore unified power quality conditioner (UPQC) is particularly reviewed to highlight the advantages over other compensating devices. An exhaustive study of literature has been carried out and most significant concepts are presented

Details

Circuit World, vol. 47 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 10 July 2018

Pankaj Khatak and H.C. Garg

Hybrid journal bearing have long been used in machines requiring large load and high speed capacity operating under wide range of temperatures. Different compensating devices are…

Abstract

Purpose

Hybrid journal bearing have long been used in machines requiring large load and high speed capacity operating under wide range of temperatures. Different compensating devices are used in for efficient operation of bearings. This paper aims to help in selection of optimum compensating device by evaluating the comparative performance of constant flow valve, capillary compensated and slot entry hybrid journal bearing under the combined influence of thermal effects and micropolar nature of lubricant.

Design/methodology/approach

The variation in micropolar parameters and viscosity change due to temperature increase of lubricant are considered in present study. Finite element method is used for combined iterative solution of micropolar Reynolds, energy and conduction equations. Micropolar lubricant is assumed to be governed by two parameters, coupling number and characteristic length. The results in the study are presented for symmetric and asymmetric configurations of hole entry and slot entry non-recessed hybrid journal bearings

Findings

The results indicate that constant flow valve compensated hole entry hybrid journal bearing is the highest performing bearing for the given range of micropolar parameters of lubricant in terms of maximum fluid pressure and dynamic coefficients.

Originality/value

The performance variations of various configurations of hybrid journal bearing are presented in a single paper. The reader can get overview of combined effects of micropolar parameters and viscosity decrease due to temperature increase of the lubricant.

Details

Industrial Lubrication and Tribology, vol. 70 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 February 2000

Edwin A. Erlbacher

There are two commercially accepted methods of force control used in automated surface finishing today. The first method, “through‐the‐arm” force control, applies force using the…

1209

Abstract

There are two commercially accepted methods of force control used in automated surface finishing today. The first method, “through‐the‐arm” force control, applies force using the position of all the robot axes in unison. The second method, “around‐the‐arm” force control, uses the robot for positioning motion only, and applies a controlled force through an auxiliary‐compliant end‐of‐arm tool. Discusses the theory, applicability and features of each of these two technologies.

Details

Industrial Robot: An International Journal, vol. 27 no. 1
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 18 January 2013

Soebhaash Dihal, Harry Bouwman, Mark de Reuver, Martijn Warnier and Christer Carlsson

The purpose of this conceptual paper is to explore the meaning of cloud computing for mobile communication. The paper answers the question “what is mobile cloud computing?” and

3102

Abstract

Purpose

The purpose of this conceptual paper is to explore the meaning of cloud computing for mobile communication. The paper answers the question “what is mobile cloud computing?” and how is it related to the generic cloud computing concept?

Design/methodology/approach

This is an explanatory conceptual paper, based on literature review and exploring potential use cases, focused on the use of mobile cloud for service, platform or infrastructure access. The authors exclude the discussion of the traditional cloud concept in back office processes of telecom operators, and service providers.

Findings

Where cloud computing is focused on pooling of resources, mobile technology is focused on pooling and sharing of resources locally enabling alternative use cases for mobile infrastructure, platforms and service delivery. The paper discusses relevant concepts and offers examples of use cases.

Research limitations/implications

The value of mobile cloud solutions is not yet explicit, but needs further attention. Research should focus on the relation between mobile cloud computing, platforms and eco systems. From a user perspective the willingness to share pooled resources needs further attention.

Practical implications

Mobile cloud computing offers the possibility that disruptive applications might impact the mobile eco system; reinforcing or weakening business models of core players like handset providers, telecom operators, and service providers.

Originality/value

A lot of attention is paid to cloud computing and to platform discussions, papers on mobile cloud are scarce. This paper offers the current state of the art and a research outlook.

Article
Publication date: 1 January 1989

M.K. Robinson, N.M. Shorrocks, R.W. Bicknell, P. Watson and D.J. Pedder

A new lass of sensors for thermal imaging and detection in the infra‐red band is emerging which exploits the pyroelectric effect in ferroelectric materials. These sensors, which…

Abstract

A new lass of sensors for thermal imaging and detection in the infra‐red band is emerging which exploits the pyroelectric effect in ferroelectric materials. These sensors, which are fabricated in the form of large linear or two‐dimensional arrays of detectors interfaced to a silicon readout circuit, do not require cooling for their operation, in contrast to the photon detection based thermal imagers. They thus have the potential for low cost thermal detection and imaging. This paper examines the design of these arrays and the technologies employed in their fabrication, with particular attention to their specialised packaging requirements, by reference to a range of linear and two‐dimensional pyroelectric array devices that have been fabricated in this laboratory.

Details

Microelectronics International, vol. 6 no. 1
Type: Research Article
ISSN: 1356-5362

Article
Publication date: 26 August 2014

Sekharan Sreejith and Sishaj P. Simon

The aim of this paper is to compare the performance of static VAR compensator (SVC) and unified power flow controller (UPFC) in dynamic economic dispatch (DED) problem. DED…

Abstract

Purpose

The aim of this paper is to compare the performance of static VAR compensator (SVC) and unified power flow controller (UPFC) in dynamic economic dispatch (DED) problem. DED schedules the online generator outputs with the predicted load demands over a certain period so that the electric power system is operated most economically. During last decade, flexible alternating current transmission systems (FACTS) devices are broadly used for maximizing the loadability of existing power system transmission networks. However, based on the literature survey, the performance of SVC and UPFC incorporated in the DED problem and its cost–benefit analysis are not discussed earlier in any of the literature.

Design/methodology/approach

Here, the DED problem is solved applying ABC algorithm incorporating SVC and UPFC. The following conditions are investigated with the incorporation of SVC and UPFC into DED problem: the role of SVC and UPFC for improving the power flow and voltage profile and the approximate analysis on cost recovery and payback period with SVC and UPFC in DED problem.

Findings

The incorporation of FACTS devices reduces the generation cost and improves the stability of the system. The percentage cost recovered with FACTS devices is estimated approximately using equated monthly installment (EMI) and non-EMI scheme. It is clear from the illustrations that the installation of FACTS devices is profitable after a certain period.

Research limitations/implications

In this research work, the generation cost with FACTS devices is only taken into account while calculating the profit. The other benefits like congestion management, cost gained due to land and cost due to stability issues are not considered. For future work, these things can be considered while calculating the benefit.

Originality/value

The originality of the work is incorporation of FACTS devices in DED problem and approximate estimation of recovery cost with FACTS devices in DED problem.

Details

International Journal of Energy Sector Management, vol. 8 no. 3
Type: Research Article
ISSN: 1750-6220

Keywords

Article
Publication date: 6 May 2020

Yassine Bouteraa, Ismail Ben Abdallah and Ahmed Elmogy

The purpose of this paper is to design and develop a new robotic device for the rehabilitation of the upper limbs. The authors are focusing on a new symmetrical robot which can be…

Abstract

Purpose

The purpose of this paper is to design and develop a new robotic device for the rehabilitation of the upper limbs. The authors are focusing on a new symmetrical robot which can be used to rehabilitate the right upper limb and the left upper limb. The robotic arm can be automatically extended or reduced depending on the measurements of the patient's arm. The main idea is to integrate electrical stimulation into motor rehabilitation by robot. The goal is to provide automatic electrical stimulation based on muscle status during the rehabilitation process.

Design/methodology/approach

The developed robotic arm can be automatically extended or reduced depending on the measurements of the patient's arm. The system merges two rehabilitation strategies: motor rehabilitation and electrical stimulation. The goal is to take the advantages of both approaches. Electrical stimulation is often used for building muscle through endurance, resistance and strength exercises. However, in the proposed approach the electrical stimulation is used for recovery, relaxation and pain relief. In addition, the device includes an electromyography (EMG) muscle sensor that records muscle activity in real time. The control architecture provides the ability to automatically activate the appropriate stimulation mode based on the acquired EMG signal. The system software provides two modes for stimulation activation: the manual preset mode and the EMG driven mode. The program ensures traceability and provides the ability to issue a patient status monitoring report.

Findings

The developed robotic device is symmetrical and reconfigurable. The presented rehabilitation system includes a muscle stimulator associated with the robot to improve the quality of the rehabilitation process. The integration of neuromuscular electrical stimulation into the physical rehabilitation process offers effective rehabilitation sessions for neuromuscular recovery of the upper limb. A laboratory-made stimulator is developed to generate three modes of stimulation: pain relief, massage and relaxation. Through the control software interface, the physiotherapist can set the exercise movement parameters, define the stimulation mode and record the patient training in real time.

Research limitations/implications

There are certain constraints when applying the proposed method, such as the sensitivity of the acquired EMG signals. This involves the use of professional equipment and mainly the implementation of sophisticated algorithms for signal extraction.

Practical implications

Functional electrical stimulation and robot-based motor rehabilitation are the most important technologies applied in post-stroke rehabilitation. The main objective of integrating robots into the rehabilitation process is to compensate for the functions lost in people with physical disabilities. The stimulation technique can be used for recovery, relaxation and drainage and pain relief. In this context, the idea is to integrate electrical stimulation into motor rehabilitation based on a robot to obtain the advantages of the two approaches to further improve the rehabilitation process. The introduction of this type of robot also makes it possible to develop new exciting assistance devices.

Originality/value

The proposed design is symmetrical, reconfigurable and light, covering all the joints of the upper limbs and their movements. In addition, the developed platform is inexpensive and a portable solution based on open source hardware platforms which opens the way to more extensions and developments. Electrical stimulation is often used to improve motor function and restore loss of function. However, the main objective behind the proposed stimulation in this paper is to recover after effort. The novelty of the proposed solution is to integrate the electrical stimulation powered by EMG in robotic rehabilitation.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 12 March 2014

Richard Fleming and Shima Sum

The purpose of this paper is to assess the empirical support for the use of assistive technology in the care of people with dementia as an intervention to improve independence…

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Abstract

Purpose

The purpose of this paper is to assess the empirical support for the use of assistive technology in the care of people with dementia as an intervention to improve independence, safety, communication, wellbeing and carer support.

Design/methodology/approach

A total of 232 papers were identified as potentially relevant. Inclusion criteria were: studies published between 1995 and 2011, incorporated a control group, pre-test-post-test, cross sectional or survey design, type of interventions and types of participants. The 41 papers that met criteria were subjected to an assessment of their validity using the model provided by Forbes. Following the assessment seven papers were considered as strong, ten moderate and 24 weak. The review is presented around the following topics: independence, prompts and reminders; safety and security; leisure and lifestyle, communication and telehealth; and therapeutic interventions.

Findings

The literature exploring the use of assistive technologies for increasing independence and compensating for memory problems illustrate the problems of moving from the laboratory to real life. The studies are usually limited by very small samples, high drop-out rates, very basic statistical analyses and lack of adjustment for multiple comparisons and poor performance of the technology itself.

Originality/value

Research to date has been unable to establish a positive difference to the lives of people with dementia by the general use of the assistive technology reviewed here.

Details

Journal of Assistive Technologies, vol. 8 no. 1
Type: Research Article
ISSN: 1754-9450

Keywords

Article
Publication date: 1 June 2005

Suat Canbazoğlu and Fazıl Canbulut

The main objective of this study was to obtain the flow restricting capacity by determining their flow coefficients and to investigate the unsteady flow with low Reynolds number…

1809

Abstract

Purpose

The main objective of this study was to obtain the flow restricting capacity by determining their flow coefficients and to investigate the unsteady flow with low Reynolds number in the flow‐restricting devices such as orifices and capillary tubes having small diameters.

Design/methodology/approach

There is an enormous literature on the flow of Newtonian fluids through capillaries and orifices particularly in many application fields of the mechanical and chemical engineering. But most of the experimental results in literature are given for steady flows at moderate and high Reynolds numbers (Re>500). In this study, the unsteady flow at low Reynolds number (10<Re<650) through flow‐restricting devices such as orifices and capillary tubes having very small diameters between 0.35 and 0.70 mm were experimentally investigated.

Findings

The capillary tubes have much more capillarity property with respect to equal diameter orifices. Increasing the ratio of capillary tube length to tube diameter and decreasing the ratio of orifice diameter to pipe diameter before orifice increase the throttling or restricting property of the orifices and the capillary tubes. The orifices can be preferred to the capillary tubes having the same diameter at the same system pressure for the hydraulic systems or circuits requiring small velocity variations. The capillary tubes provide higher pressure losses and they can be also used as hydraulic accumulators in hydraulic control devices to attenuate flow‐induced vibrations because of their large pressure coefficients. An important feature of the results obtained for capillary tubes and small orifices is that as the d/D for orifices increases and the L/d reduces for capillary tubes, higher values C are obtained and the transition from viscous to inertia‐controlled flow appears to take place at lower Reynolds numbers. This may be explained by the fact that for small orifices with high d/D ratios and for capillary tubes with small L/d ratios, the losses due to viscous shear are small. Another important feature of the results is that the least variations in C for small orifices and the higher variations in C for capillary tubes occur when the d/D and L/d ratios are smallest. This has favourable implications in hydraulic control devices since a constant value for the C may be assumed even at relatively low values of Re.

Originality/value

To the authors' knowledge, there is not enough information in the literature about the flow coefficients of unsteady flows through capillary tubes and small orifices at low Reynolds numbers. This paper fulfils this gap.

Details

Industrial Lubrication and Tribology, vol. 57 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 12 September 2016

Rajneesh Kumar and Suresh Verma

In the present scenario of high-speed machines, the use of non-circular hole-entry bearing configuration, i.e. two-lobe, multi-lobe, lemon bore, etc., has becomes unavoidable, as…

Abstract

Purpose

In the present scenario of high-speed machines, the use of non-circular hole-entry bearing configuration, i.e. two-lobe, multi-lobe, lemon bore, etc., has becomes unavoidable, as the journal bearings with non-circular configurations provide better stability at high operating speed and heavy dynamic loading. Further, this research aims to show that the presence of micro particles in the lubricants greatly affects performance of the bearings, as their presence leads to non-Newtonian behaviors of the lubricant. Therefore, to consider the effect of these micro particles, the lubricant is modeled as a micropolar lubricant. The present work analyzes the effect of these micropolar lubricants on the performance of hole-entry circular and non-circular (two-lobe) hybrid journal bearings compensated with constant flow valve restrictor and compares with that of Newtonian lubricants.

Design/methodology/approach

The modified Reynolds equation governing the laminar flow of iso-viscous, incompressible micropolar lubricant in the clearance space of a journal bearing system has been solved using finite element method and appropriate boundary conditions. Further, a comparative analysis between circular and non-circular (two-lobe) hybrid journal bearing compensated with constant flow valve restrictor operating with Newtonian and micropolar lubricant has been presented.

Findings

The numerically simulated results reveal that the non-circular bearing configuration provides better performance vis-à-vis the circular bearing configuration. Further, the increase in the micropolar effect of the lubricant enhances the performance of circular and the non-circular bearing configurations compared with the Newtonian lubricant. Also, in the case of the non-circular bearing configuration with an offset factor (δ = 1.5), the bearing performance improved compared with (δ = 1.25).

Originality/value

Many research studies have been done in the area of non-circular hybrid journal bearing with Newtonian lubricants with different types of restrictors, but the non-circular hole-entry constant flow valve-compensated hybrid journal bearing operating with the micropolar lubricant has not been analyzed. Therefore, in the present work, an effort has been made to fill this research gap.

Details

Industrial Lubrication and Tribology, vol. 68 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

1 – 10 of over 7000