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Article
Publication date: 8 June 2022

Chinnaraj Gnanavel and Kumarasamy Vanchinathan

These implementations not only generate excessive voltage levels to enhance the quality of power but also include a detailed investigating of the various modulation methods and…

194

Abstract

Purpose

These implementations not only generate excessive voltage levels to enhance the quality of power but also include a detailed investigating of the various modulation methods and control schemes for multilevel inverter (MLI) topologies. Reduced harmonic modulation technology is used to produce 11-level output voltage with the production of renewable energy applications. The simulation is done in the MATLAB/Simulink for 11-level symmetric MLI and is correlated with the conventional inverter design.

Design/methodology/approach

This paper is focused on investigating the different types of asymmetric, symmetric and hybrid topologies and control methods used for the modular multilevel inverter (MMI) operation. Classical MLI configurations are affected by performance issues such as poor power quality, uneconomic structure and low efficiency.

Findings

The variations in both carrier and reference signals and their performance are analyzed for the proposed inverter topologies. The simulation result compares unipolar and bipolar pulse-width modulation (PWM) techniques with total harmonic distortion (THD) results. The solar-fed 11-level MMI is controlled using various modulation strategies, which are connected to marine emergency lighting loads. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by using SPARTAN 3A field programmable gate array (FPGA) board and the least harmonics are obtained by improving the power quality.

Originality/value

The simulation result compares unipolar and bipolar PWM techniques with THD results. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by a SPARTAN 3A field programmable gate array (FPGA) board, and the power quality is improved to achieve the lowest harmonics possible.

Details

Circuit World, vol. 49 no. 4
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 1 May 1966

L.H. Bridges

Offshore drilling rigs have been operating for many years, but it is only fairly recently that they have been used much in British and European waters. Conditions in these waters…

66

Abstract

Offshore drilling rigs have been operating for many years, but it is only fairly recently that they have been used much in British and European waters. Conditions in these waters add to the problems involved in protecting offshore rigs, which are more complex than those affecting normal shipping

Details

Anti-Corrosion Methods and Materials, vol. 13 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 January 1951

WE do not apologize for devoting space this month to the Scottish Government Report on Libraries. It is, as our writers affirm, an important document and many themes for debate…

31

Abstract

WE do not apologize for devoting space this month to the Scottish Government Report on Libraries. It is, as our writers affirm, an important document and many themes for debate may emerge from it. If a reading circle of young librarians were formed in any district it could consider this document page by page with much profit. It is, for an official document, interesting in style. It starts many old ideas, it has the verve and certainty which we look for in the amateur rather than the professional writer. To some of its statements, for example its assertion that “libraries have reached or are approaching a temporary limit to their usefulness, because the schools have not yet given adequate training in the use and power of books,” librarians may well ask “why?” in relation to the second part of this statement; and they certainly refuse to admit or believe the first part of it. In fact, the use of libraries in such universal manner is largely the result of the work of modern libraries for children. The librarian teaches children what to read. We have not reached any such limit as is affirmed ; we are indeed only on the margin of our possibilities.

Details

New Library World, vol. 53 no. 14
Type: Research Article
ISSN: 0307-4803

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Publication date: 24 November 2011

Lilia Murray

The purpose of this chapter is to present a general review of free or inexpensive methods of implementing the following mobile services in libraries: Library Websites, Short…

Abstract

The purpose of this chapter is to present a general review of free or inexpensive methods of implementing the following mobile services in libraries: Library Websites, Short Message Service (SMS) reference, and Mobile Online Public Access Catalogs (MOPACs). The findings were based on a literature review of materials that discussed mobile technologies in libraries. The findings conclude that libraries with tight budgets should approach their mobilization project in terms of stages, developing content and services sequentially from passive formats, which require little input, to more dynamic items, which entail greater interaction. Most free and inexpensive mobile services are geared toward passive formats, providing a starting point for libraries with limited budgets. Scope of the chapter is limited to public and university libraries and initiatives for smartphones. Prices listed are in USD as of January 2011 and may be subject to change. The costs of training, management, and development time by libraries were not factored into the costs. Mobile services have become one of the biggest new library trends. Simply keeping abreast of library service options made possible through advances in mobile technology can be a challenge. In addition, tough economic times have prevented many libraries from actually implementing mobile services. This chapter discusses a number of ways for libraries to create their own mobile initiative with little to no money at all—except of course for the hidden cost of staff effort.

Details

Librarianship in Times of Crisis
Type: Book
ISBN: 978-1-78052-391-0

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Article
Publication date: 5 February 2018

Aubrey Harvey Chaputula and Stephen Mutula

The purpose of this paper is to present findings of a study conducted to determine eReadiness status of public university libraries in Malawi to use mobile phones in the provision…

1264

Abstract

Purpose

The purpose of this paper is to present findings of a study conducted to determine eReadiness status of public university libraries in Malawi to use mobile phones in the provision of library and information services.

Design/methodology/approach

The researcher carried out in-depth semi-structured interviews with university/college librarians and information and communications technology (ICT) directors using interview guides. Students were also administered with a survey questionnaire that contained closed- and some open-ended questions. Proceedings of the interviews were recorded using a tape recorder whilst backup notes were recorded in a notebook. Qualitative data were transcribed and analysed using NVivo software whilst quantitative data were analysed using SPPS.

Findings

The study findings revealed that institutions studied had the ICT infrastructure necessary for offering library and information services on the mobile phone platform. Moreover, students had mobile phones which were connected to internet to facilitate their access to services offered. However, the institutions covered by this study did not have operational ICT policies to govern the operations of library and information services offered through mobile phones although draft ICT policies were available. The study further concluded that though the human resources required to manage the provision of library and information services through mobile phones in the institutions studied were available, they did not have the necessary skills and numbers to provide quality services. Other findings revealed that attitudes of library staff and students to the offering and access to services through mobile phones were positive. The study also revealed that there are some factors that could impact the offering of library services through mobile phones.

Research limitations/implications

Although Malawi has four public universities, this study only focused on three of them. Moreover, academic staff is another important user group of academic libraries. In this case, findings reported in this paper only focus on students. This implies that library’s readiness to offer services through mobile phones to this group remains unknown hence may have to be covered by future studies. Much as the study incorporated a quantitative strand in addition to the qualitative one, it neither involved theory testing nor confirmation as is the case with other related studies. This implies that the two theories used in this study (the unified theory of acceptance and use of technology and the technology-organisation-environment) were not used in the strict sense, which is empirical at the core, but rather to put the problem studied in the context of other related studies.

Practical implications

The findings have practical implications in that they can be used for planning the implementation of library and information services through mobile phones in public university libraries in Malawi. Other related institutions can also use the findings as a reference point in planning the implementation of similar services.

Originality/value

Studies relating to the use of mobile phones in the delivery of library and information services have not been conducted in public universities in Malawi. Findings of this study will, therefore, inform researchers intending to conduct similar or related studies not only in public universities in Malawi but other related institutions as well.

Details

Library Hi Tech, vol. 36 no. 2
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 11 November 2014

Ivana Pažur

The purpose of this paper is to get an insight in users’ opinion on library resources/services on small screen mobile devices. Objectives were to establish which types of small…

892

Abstract

Purpose

The purpose of this paper is to get an insight in users’ opinion on library resources/services on small screen mobile devices. Objectives were to establish which types of small screen mobile devices are used and to find out is there a tendency for using academic and educational contents on such devices. Furthermore, aim was to identify whether the users need mobile friendly library web site and services at all. Also, what library resources/services and to what extent respondents consider as the important ones for mobile friendly customization. Finally the results would serve as an orientation in building mobile friendly library web site and services. The author believed that the users were still unaware of the possibility of accessing library web sites and services through mobile devices in general; therefore, this survey also had a role of raising awareness and stimulating their interest.

Design/methodology/approach

The survey was focussed on small screen mobile devices with screen size up to seven inches (17.1 cm). Data collection was performed through a questionnaire containing ten questions. The questionnaire was created by LimeSurvey tool, and for mobile optimized version SurveyMonkey.com service was used too. The authors received 295 questionnaires, out of which 285 were taken into account.

Findings

The survey found that the largest number of respondents own smartphone/tablet/phablet. The results show that small screen devices are, to some extent, used for educational, academic and informational purposes (reading of e-books and e-journals, education, data checking, internet searching and searching of handy information), but non-academic purposes still predominate (texting, reading e-mails, phone calls, taking pictures). Overall 64 percent of the respondents has expressed need for small screen mobile devices customized library resources/services, but there are 30 percent of undecided respondents. Croatian Scientific Bibliography, e-journals database (EZB), online databases, contact information and lecture halls reservations, has been resources/services requested by respondents to be available in a mobile friendly mode.

Originality/value

The survey examines users’ opinion on a new library service before its implementation. Besides giving us a precise insight into the Rudjer Bošković Institute library users’ interest and needs for mobile friendly customization of existing library resource/service, survey gives a unique insight into the correlation of age and gender of the respondents and their answers to the question about having a small screen mobile device and opinion about the customization of library resources and services. To the author’s knowledge, this is the first users’ survey on this topic in Croatia.

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Article
Publication date: 1 May 1975

Freeman Chemicals Ltd have gained Approved Firms Schedule from the Director of Materials Quantity Assurance, Ministry of Defence.

7

Abstract

Freeman Chemicals Ltd have gained Approved Firms Schedule from the Director of Materials Quantity Assurance, Ministry of Defence.

Details

Pigment & Resin Technology, vol. 4 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 16 March 2015

Catharine Bomhold

The purpose of this paper is to describe the availability of discovery functions on mobile devices at academic research libraries in order to determine if research libraries are…

1985

Abstract

Purpose

The purpose of this paper is to describe the availability of discovery functions on mobile devices at academic research libraries in order to determine if research libraries are providing the mobile services that students believe that they need for academic success.

Design/methodology/approach

The researcher surveyed 53 academic library mobile apps and mobile web sites at Carnegie rated RU/VH universities to determine the number and variety of discovery functions available.

Findings

All of the libraries had some level of research functions available, but there was a discrepancy between those that offered a full range of services and those that offered a minimal level.

Research limitations/implications

Due to the transitory nature of the electronic universe, the data offered represents the state of academic library research services in a single moment in time and is subject to change.

Practical implications

The research provides other libraries with a description of what comprises an adequate suite of essential services and a way to evaluate their own library’s offerings.

Originality/value

This is the first study to evaluate and quantify the level of services provided by libraries at Carnegie Foundation RU/VH institutions.

Details

Library Hi Tech, vol. 33 no. 1
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 30 August 2011

Ding Hooi Ting, Suet Fong Lim, Tanusina Siuly Patanmacia, Ca Gie Low and Gay Chuan Ker

This study aims to investigate the effect of convenience, social needs and social influences on university students' dependency towards smartphones and the impact on future…

16771

Abstract

Purpose

This study aims to investigate the effect of convenience, social needs and social influences on university students' dependency towards smartphones and the impact on future purchase behaviour in Malaysia.

Design/methodology/approach

Hypotheses were tested with a random and judgemental sampling (students who use smartphones only) of 358 university students using a face‐to‐face survey method. Structural equation modelling was used to test the hypotheses.

Findings

The results indicated that university students' dependency on smartphones is influenced by convenience, social needs and social influences and dependency is positively related with future purchase behaviour.

Research limitations/implications

Results of this study are limited by the absence of equal distribution across different races and culture of university students.

Originality/value

The domain of research, smartphones, is a new technology that is largely adopted and deserves investigation for future mobile market strategies. Although this research of smartphone dependency is limited to universities, this study contributes to the field by adding new investigation in this new target segment of smartphone users.

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Article
Publication date: 13 March 2017

Gulcin Kubat

The purpose of this study is to search for any evidence for university libraries that are accessible by mobile technology in Turkey as relevant models of the future; having regard…

1197

Abstract

Purpose

The purpose of this study is to search for any evidence for university libraries that are accessible by mobile technology in Turkey as relevant models of the future; having regard to the fact that smartphones will very soon become the standard means by which the internet is accessed, and the rates of connection from mobile devices will supersede those which are computer-based.

Design/methodology/approach

In the study, both domestic and foreign literature surveys were undertaken to determine which mobile library services are offered in university libraries. Thirty random central libraries of both private and state universities were selected from across the seven regions of Turkey. To gather data, a 26-question electronic survey was generated and e-mailed to the library managers. The questions were based on findings regarding the mobile library services provided by university libraries around the world.

Findings

By examining the survey results, it was determined that Turkish university libraries utilise a comparable level of mobile technology and demonstrate a similar level of care with regard to the services they offer. There are mobile sites (separate sites or mobile sites as applications), mobile library catalogues, short messaging services, chat rooms, consultations via instant messaging tools, mobile device-lending services, and augmented reality and QR code applications.

Research limitations/implications

In Turkey, the structures of university libraries operate under variable conditions because of the lack of established standards. This causes negative results for the delivery of library services. For this reason, university library standards should be set practicable as soonas reasonable, considering the social/economic and cultural structure of the country.

Practical implications

Owing to the transformative effect technology and the internet have had on services information and communication technologies, infrastructure has been added as a sixth element to the five traditional library items, namely, building budget personnel collection and users. Globalisation through the web has resulted in the individualisation of services and the slogan content is king has been changed to the customer experience is king. Fundamental library services are being adapted to allow mobile technology access, and this approach best reflects the new slogan. Therefore, the university library of the future may well be the one entirely based on mobile technology.

Social implications

Mobile devices lead to new forms of engagement with student learning; so academic libraries are expected to be strong partners in the teaching and learning processes of their institution.

Originality/value

The hypothesis of this study is that a university library accessible by mobile technology will be the model of the future, and its purpose is to search for any evidence for which the university libraries in Turkey are prepared to meet this challenge. This study is also meaningful because there have not been any study of Turkish university libraries in terms of mobile library services to users. This paper is the first time that a comprehensive study has been made of current mobile technology-based services, and is also the first comparison of the applications in Turkish university libraries. Additionally, paper synthesises developments and provides suggestions for the future.

Details

Information and Learning Science, vol. 118 no. 3/4
Type: Research Article
ISSN: 2398-5348

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