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Article
Publication date: 3 July 2017

Fiaz Ahmad, Kabir Muhammad Abdul Rashid, Akhtar Rasool, Esref Emre Ozsoy, Asif Sabanoviç and Meltem Elitas

To propose an improved algorithm for the state estimation of distribution networks based on the unscented Kalman filter (IUKF). The performance comparison of unscented Kalman…

Abstract

Purpose

To propose an improved algorithm for the state estimation of distribution networks based on the unscented Kalman filter (IUKF). The performance comparison of unscented Kalman filter (UKF) and newly developed algorithm, termed Improved unscented Kalman Filter (IUKF) for IEEE-30, 33 and 69-bus radial distribution networks for load variations and bad data for two measurement noise scenarios, i.e. 30 and 50 per cent are shown.

Design/methodology/approach

State estimation (SE) plays an instrumental role in realizing smart grid features like distribution automation (DA), enhanced distribution generation (DG) penetration and demand response (DR). Implementation of DA requires robust, accurate and computationally efficient dynamic SE techniques that can capture the fast changing dynamics of distribution systems more effectively. In this paper, the UKF is improved by changing the way the state covariance matrix is calculated, to enhance its robustness and accuracy under noisy measurement conditions. UKF and proposed IUKF are compared under the cummulative effect of load variations and bad data based on various statistical metrics such as Maximum Absolute Deviation (MAD), Maximum Absolute Per cent Error (MAPE), Root Mean Square Error (RMSE) and Overall Performance Index (J) for three radial distribution networks. All the simulations are performed in MATLAB 2014b environment running on an hp core i5 laptop with 4GB memory and 2.6 GHz processor.

Findings

An Improved Unscented Kalman Filter Algorithm (IUKF) is developed for distribution network state estimation. The developed IUKF is used to predict network states (voltage magnitude and angle at all buses) and measurements (source voltage magnitude, line power flows and bus injections) in the presence of load variations and bad data. The statistical performance of the coventional UKF and the proposed IUKF is carried out for a variety of simulation scenarios for IEEE-30, 33 and 69 bus radial distribution systems. The IUKF demonstrated superiority in terms of: RMSE; MAD; MAPE; and overall performance index J for two measurement noise scenarios (30 and 50 per cent). Moreover, it is shown that for a measurement noise of 50 per cent and above, UKF fails while IUKF performs.

Originality/value

UKF shows degraded performance under high measurement noise and fails in some cases. The proposed IUKF is shown to outperform the UKF in all the simulated scenarios. Moreover, this work is novel and has justified improvement in the robustness of the conventional UKF algorithm.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 29 June 2010

Anna Tanskanen, Tommi Raussi, Jarmo Partanen and Juha Lohjala

The purpose of this paper is to examine the key outage‐cost‐influencing applications (fault location and network restoration, fault reporting, field crew management, and…

1172

Abstract

Purpose

The purpose of this paper is to examine the key outage‐cost‐influencing applications (fault location and network restoration, fault reporting, field crew management, and reconfiguration) of the distribution management system (DMS) and analyzes the benefits provided by them. The objective of the study is an evaluation of their influence on outage costs deriving from the adoption of automatic equipment in managing distribution systems.

Design/methodology/approach

Cost and benefit calculations in this paper are made for a typical North European rural medium‐voltage network. The benefits are calculated in terms of outage costs for each of the above‐presented applications and compared with the investment cost, including the annual cost of maintenance, of the DMS. The empirical results and validation of the theoretical calculations are performed by an electric utility, where the DMS benefit evaluation is taking place.

Findings

By capitalizing the applications of the DMS, it is possible to acquire considerable benefits in outage costs. It is shown that the greatest cost‐based benefits are obtained from the fault location and field crew management applications. The case study further shows that the DMS can reduce the operation costs of utilities.

Research limitations/implications

The calculations are based on network expert assumptions about System Average Interruption Duration (SAIDI), carried out for a specific overhead‐line network operating in a specific European rural medium‐voltage environment. Sharing of utilities' de facto SAIDI results as a basis for calculations would decrease the need for subjective expert assumptions in the future analyses.

Practical implications

Application of the proposed framework for decision making and lessons learned can support electric utilities when planning for unbundling and strategic target‐setting in the unbundled business model.

Originality/value

There are few reports available on similar actual DMS‐application‐based cost benefits due to the nature of private utility information that is preferably not disclosed.

Details

International Journal of Energy Sector Management, vol. 4 no. 2
Type: Research Article
ISSN: 1750-6220

Keywords

Book part
Publication date: 5 October 2018

Nima Gerami Seresht, Rodolfo Lourenzutti, Ahmad Salah and Aminah Robinson Fayek

Due to the increasing size and complexity of construction projects, construction engineering and management involves the coordination of many complex and dynamic processes and…

Abstract

Due to the increasing size and complexity of construction projects, construction engineering and management involves the coordination of many complex and dynamic processes and relies on the analysis of uncertain, imprecise and incomplete information, including subjective and linguistically expressed information. Various modelling and computing techniques have been used by construction researchers and applied to practical construction problems in order to overcome these challenges, including fuzzy hybrid techniques. Fuzzy hybrid techniques combine the human-like reasoning capabilities of fuzzy logic with the capabilities of other techniques, such as optimization, machine learning, multi-criteria decision-making (MCDM) and simulation, to capitalise on their strengths and overcome their limitations. Based on a review of construction literature, this chapter identifies the most common types of fuzzy hybrid techniques applied to construction problems and reviews selected papers in each category of fuzzy hybrid technique to illustrate their capabilities for addressing construction challenges. Finally, this chapter discusses areas for future development of fuzzy hybrid techniques that will increase their capabilities for solving construction-related problems. The contributions of this chapter are threefold: (1) the limitations of some standard techniques for solving construction problems are discussed, as are the ways that fuzzy methods have been hybridized with these techniques in order to address their limitations; (2) a review of existing applications of fuzzy hybrid techniques in construction is provided in order to illustrate the capabilities of these techniques for solving a variety of construction problems and (3) potential improvements in each category of fuzzy hybrid technique in construction are provided, as areas for future research.

Details

Fuzzy Hybrid Computing in Construction Engineering and Management
Type: Book
ISBN: 978-1-78743-868-2

Keywords

Book part
Publication date: 1 November 2007

Irina Farquhar and Alan Sorkin

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative…

Abstract

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

Details

The Value of Innovation: Impact on Health, Life Quality, Safety, and Regulatory Research
Type: Book
ISBN: 978-1-84950-551-2

Book part
Publication date: 11 October 2023

Javier Peña Capobianco

The objective of this chapter is to identify the key characteristics of Global Services businesses that will thrive and achieve success in the future. These factors are integrated…

Abstract

The objective of this chapter is to identify the key characteristics of Global Services businesses that will thrive and achieve success in the future. These factors are integrated into three main pillars, which we refer to as the Triple-Win. The first and most obvious pillar is technology as a tool. The second pillar is the design and sustainability of the business model, without which the previous factor would be merely a cost and not an investment. And last but not the least, there is the purpose which gives meaning to the proposal, focusing on the human being and their environment. The DIDPAGA business model sits at the intersection of these three elements.

Details

The New Era of Global Services: A Framework for Successful Enterprises in Business Services and IT
Type: Book
ISBN: 978-1-83753-627-6

Keywords

Book part
Publication date: 8 March 2018

Victoria Chiu, Qi Liu and Miklos A. Vasarhelyi

The advances and continuous development of technology have been identified as significant influences on the accounting profession (AICPA, 1998). In the last twenty years, both…

Abstract

The advances and continuous development of technology have been identified as significant influences on the accounting profession (AICPA, 1998). In the last twenty years, both academia and the accounting profession have been giving much attention to the demand and opportunity for audits to be performed automatically, continuously and in nearly real time. This paper presents a comprehensive review of continuous auditing research by providing an overview of the emergence and growth of the continuous auditing literature and classifying the extant continuous auditing research on the basis of four research characteristics indicated by a newly developed research taxonomy.

Article
Publication date: 1 June 1985

The librarian and researcher have to be able to uncover specific articles in their areas of interest. This Bibliography is designed to help. Volume IV, like Volume III, contains…

12676

Abstract

The librarian and researcher have to be able to uncover specific articles in their areas of interest. This Bibliography is designed to help. Volume IV, like Volume III, contains features to help the reader to retrieve relevant literature from MCB University Press' considerable output. Each entry within has been indexed according to author(s) and the Fifth Edition of the SCIMP/SCAMP Thesaurus. The latter thus provides a full subject index to facilitate rapid retrieval. Each article or book is assigned its own unique number and this is used in both the subject and author index. This Volume indexes 29 journals indicating the depth, coverage and expansion of MCB's portfolio.

Details

Management Decision, vol. 23 no. 6
Type: Research Article
ISSN: 0025-1747

Keywords

Article
Publication date: 1 April 1983

Cavan McCarthy

Automated systems can be found in about forty locations in Brazil, including both libraries and information systems; they are usually simple systems, developed and operating in…

Abstract

Automated systems can be found in about forty locations in Brazil, including both libraries and information systems; they are usually simple systems, developed and operating in isolation. An in‐depth survey of twenty‐two automated library systems revealed seventeen automated catalogues, nine circulation systems and five acquisition systems; in all cases the number of transactions was low by anglo‐American standards. Seven internal indexing systems were also noted; public indexing systems were not always appropriate for the needs of specific institutions. Brazilian libraries have made a firm start in the automation field and will doubtless continue to automate, although this will rarely be their major priority.

Details

Program, vol. 17 no. 4
Type: Research Article
ISSN: 0033-0337

Article
Publication date: 23 December 2019

Joakim Hans Kembro and Andreas Norrman

The purpose of this study is to explore warehouse configuration in omni-channel retailing.

2993

Abstract

Purpose

The purpose of this study is to explore warehouse configuration in omni-channel retailing.

Design/methodology/approach

A multiple case study is conducted with six large omni-channel retailers from three different sectors.

Findings

The study shows an increase in the number, variation and frequency of flows passing through omni-channel warehouses. Along with an increased variety of stock keeping units (including singles vs multipacks), there is an increase in the complexity of planning and coordination of order fulfillment. Retailers test a mix of different solutions for storage and picking and partly shift focus to advanced sorting operations. The companies already have or plan to invest in substantial automation systems, which emphasize the importance of capturing and using accurate master data.

Research limitations/implications

The study highlights the need to understand the interrelations and co-development of configuration elements in omni-channel warehousing. The findings also suggest that a successful transformation requires increased collaboration with upstream and downstream partners. Conceptual models are developed to illustrate strategies and development paths in omni-channel warehousing, and suggestions for future research are summarized in a research agenda. A research limitation is the focus on Swedish retailers in three sectors (fashion, consumer electronics and DIY/construction material). Future studies can include additional sectors, extend the geographical scope and explore cross-regional differences.

Practical implications

As one of the few deeper case studies on omni-channel warehousing, practitioners will find new configurations described and analyzed here. Along with conceptual models, a synthesis of challenges and potential solutions are presented to support retailers’ practical analysis and decision making.

Originality/value

This is one of the first multiple case studies that go deeper into omni-channel warehouse configuration, which is of increasing importance to both scholars and practitioners in the field.

Details

International Journal of Physical Distribution & Logistics Management, vol. 50 no. 5
Type: Research Article
ISSN: 0960-0035

Keywords

Article
Publication date: 1 February 1992

John Ashford, Utami Hariyadi and Tina T. Nanny

A project to develop a national academic union catalogue for the 49 universities and major teacher training colleges of Indonesia has completed its design stages, and procurement…

Abstract

A project to develop a national academic union catalogue for the 49 universities and major teacher training colleges of Indonesia has completed its design stages, and procurement of software and computing equipment will follow. The operational centre, will share a site in Dépok with the University of Indonesia. Early phases of implementation will concentrate on the 12 Discipline Service Centres where expertise and resources are concentrated in centres of excellence for selected subjects, to enable all students and researchers to share in this investment. In the course of the design studies, an examination was made of the library automation needs of a major university, Universitas Gadjah Mada, to ensure compatibility between national plans and end user requirements in library automation as a whole. The use of CD‐ROM is proposed as a distribution medium for the union catalogue of at least 500,000 titles. Pilot studies will be made in parallel with retrospective conversion of existing catalogues, to check out CD‐ROM production routes and explore approaches to subject indexing using multiple schemes and in several languages.

Details

Program, vol. 26 no. 2
Type: Research Article
ISSN: 0033-0337

1 – 10 of over 1000