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Walid Ghali

Aga Khan University, Institute for the Study of Muslim Civilisations, Faculty Member

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Proven excellence in the development of strong rapport with students, colleagues and administration. Exhibits particular expertise in teaching and coordination of lifelong learning programs in higher education. Inspirational teacher, experience research librarian and meticulous who encourage individual growth. Actively involved in research activities within the universities and hold many leadership positions in the field of Islamic studies.

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Papers by Walid Ghali

Old, New or Digital Philology

BRILL eBooks, Apr 25, 2023

Humour in Islamic Literature and Muslim Practices: Virtue or Vice?

Policy Press eBooks, May 26, 2022

Humour in Islamic Literature and Muslim Practices

Bristol University Press eBooks, May 26, 2022

Chapter 2 The Making of a Qurʾān Manuscript in Lamu Archipelago: The Indian Ocean Cross-cultural Influence

Edinburgh University Press eBooks, Dec 31, 2023

4 Poems in Praise of the Prophet (madīḥ) as a Citizen of the Literary World

Edinburgh University Press eBooks, Nov 30, 2022

$Research paper thumbnail of The Knowledge Quarter: The British Library\u27s New Initiative of Partnership$

The Knowledge Quarter: The British Library\u27s New Initiative of Partnership

$Research paper thumbnail of The Sanaa Palimpsest: the transmission of the Qur\u27an in the first centuries (Book Review)$

The Sanaa Palimpsest: the transmission of the Qur\u27an in the first centuries (Book Review)

Beyond digitization: The case of The Aga Khan Library

Women's Activism and New Media in the Arab World by Ahmed Al-Rawi (review)

Information & Culture, 2022

برامج التعليم الببليوجرافي في المكتبات الأكاديمية ودورها في دعم البحث العلمي

مقامات الأولياء والصالحين في الواحات Saints and Sufi Shrines in an Egyptian Oasis (Dakhla)

Memory of Egypt Magazine (ذاكرة مصر), 2021

The Sanaa Palimpsest: the transmission of the Qur'an in the first centuries (Book Review)

<i>Islamic Calligraphy</i>, by Sheila Blair

Journal of Islamic Archaeology, 2018

Economic production quantity with maintenance interruptions under random and correlated yields

International Journal of Production Research, 2016

This paper considers an economic production quantity with imperfect items where the quality of it... more This paper considers an economic production quantity with imperfect items where the quality of items produced within the same production run is correlated. Production and scheduled maintenance policies for a correlated binomial production system are investigated. We study the impact of correlation on the system performance measures and draw insights in terms of the effect of correlation on the production and maintenance policies. We also illustrate that the popular and commonly used interrupted geometric production systems can be analysed by an equivalent correlated binomial production model.

An analytical approach to estimate the expected duration and variance for iterative product development projects

Research in Engineering Design, 2015

The paper presents an analytical method for finding the expected duration and variance of a produ... more The paper presents an analytical method for finding the expected duration and variance of a product development (PD) project network. A PD project network is a stochastic activity network (such as a PERT network) which allows for probabilistic repetition of activities (i.e., activity rework). When rework is allowed, estimating the process duration and variance becomes difficult. Most existing literature refers to the use of simulation in such scenarios; however, few analytical methods exist to solve this problem. One such method is called the reward Markov chain (RMC) which only considers sequential activity networks and which we use as a starting point in our proposed method. In this paper, we extend the RMC method to solve mixed networks (i.e., a combination of parallel and sequential activities) and more complicated practical issues that may arise in PD environments, specifically coupled activities and parallel rework.

Continuous (s, S) policy with MMPP correlated demand

European Journal of Operational Research, 2015

This work considers a continuous inventory replenishment system where demand is stochastic and de... more This work considers a continuous inventory replenishment system where demand is stochastic and dependent on the state of the environment. A Markov Modulated Poisson Process (MMPP) is utilized to model the demand process where the corresponding embedded Markov Chain represents the state of the environment. The equations to calculate the system inventory measures and the number of orders per unit time are obtained for a continuous, infinite horizon and dynamically changing (s, S) policy. An efficient optimization heuristic is presented and compared to the commonly used approach of approximating the demand-count process over the lead time with a Normal distribution. An investigation of the MMPP demand process is considered where we quantify the impact of variability in the demand-count process which is due to auto-correlation. Our findings indicate that when demand correlation is high, a dynamic control, where the (s, S) policy changes with state of the environment governing the MMPP, is highly superior to the commonly used “static” heuristics. We propose two dynamic policies of varying computational complexity, and cost efficiency, depending on the class of the product (one for class A, and one for classes B and C), to handle such high-correlation situations.

Effect of deterioration on the instantaneous replenishment model with imperfect quality items

Applied Mathematical Modelling, 2014

ABSTRACT The assumptions required to justify the use of the economic order quantity model (EOQ) a... more ABSTRACT The assumptions required to justify the use of the economic order quantity model (EOQ) are rarely met. To provide mathematical models that more closely represent real-life situations, these assumptions must be relaxed. Among these assumptions are, first, items stocked are of perfect quality, and second, they preserve their characteristics during their stay in inventory. This paper considers a modified EOQ-type inventory model for a deteriorating item with unreliable supply. That is, a percentage of the on-hand inventory is wasted due to deterioration. Moreover, orders may contain a random proportion of defective items, which follow a known distribution. As soon as an order is received, a retailer conducts a screening process to identify imperfect quality items, which are salvaged as a single batch at the end of the screening process. First, a mathematical model is developed, assuming that no shortages are allowed. For that, it is assumed that the inventory level when placing an order is just enough to cover the demand during the screening period. The concavity of the profit function is established and sensitivity analysis is provided to analyze the impact of changing various model parameters on the optimal order quantity and profit. Then, the assumption of no shortages is relaxed, and a model is developed to incorporate backorders. We analyze the model with backorders numerically and provide managerial insights.

Fitting the Pht/Mt/s/c Time-Dependent Departure Process for Use in Tandem Queueing Networks

INFORMS Journal on Computing, 2013

This paper considers time-dependent Pht/Mt/s/c queueing nodes and small tandem networks of such n... more This paper considers time-dependent Pht/Mt/s/c queueing nodes and small tandem networks of such nodes. We examine characteristics of the departure processes from a multiserver queueing node; in particular, we focus on solving for the first two time-dependent moments of the departure-count process. A finite set of partial moment differential equations is developed to numerically solve for the departure-count moments over specified intervals of time [ti, ti + τi). We also present a distribution fitting algorithm to match these key characteristics with a [Formula: see text] process serving as the approximate departure process. A distribution fitting algorithm is presented for time-dependent point processes where a two-level balanced mixture of Erlang distribution is used to serve as the approximating process. We then use the [Formula: see text] approximating departure process as the approximate composite arrival process to downstream node(s) in a network of tandem queues.

Transshipment and safety stock under stochastic supply interruption in a production system

Computers & Industrial Engineering, 2012

We consider a two-echelon system with one source supplying two locations with the same product. T... more We consider a two-echelon system with one source supplying two locations with the same product. The random occurrence of interruptions at the source where downtime is also stochastic can result in stockouts at the two receiving locations. Our model studies the benefit of allowing each location to carry a safety stock where holding costs can be different at each location. The objective is to reduce overall cost at both locations. In some cases it is optimal to allow for a transshipment of inventory from the safety stock of one location to the other. We jointly solve for the optimal safety stock at each location and the optimal amount to be transshipped from a location to the other. We show that by conditioning on the transshipment direction the total cost becomes convex as a function of the safety stock levels at the receiving locations and the amount to be transshipped from a location to the other. Numerical examples are presented for different system cost parameters and probability distributions.

An instantaneous replenishment model under the effect of a sampling policy for defective items

Applied Mathematical Modelling, 2013

ABSTRACT We propose to study a EOQ-type inventory model with unreliable supply, with each order c... more ABSTRACT We propose to study a EOQ-type inventory model with unreliable supply, with each order containing a random proportion of defective items. Every time an order is received, an acceptance sampling plan is applied to the lot, according to which only a sample is inspected instead of the whole lot. If the sample conforms to the standards, i.e. if the number of imperfect items is below an “acceptance number”, no further screening is performed. Otherwise, the lot is subject to 100% screening. We formulate an integer non-linear mathematical program that integrates inventory and quality decisions into a unified profit model, to jointly determine the optimal lot size and optimal sampling plan, characterized by a sample size, and an acceptance number. The optimal decisions are determined in a way to achieve a certain average outgoing quality limit (AOQL), which is the highest proportion of defective items in the outgoing material sold to customers. We provide a counter-example demonstrating that the expected profit function, objective of the mathematical program, is not jointly concave in the lot and sample size. However, we show that for a given sampling plan, the expected profit function is concave in the lot size. A solution procedure is presented to compute the optimal solution. Numerical analysis is provided to gain managerial insights by analyzing the impact of changing various model parameters on the optimal solution. We also show numerically that the optimal profit determined using this model is significantly higher when compared to the optimal profit obtained using Salameh and Jaber (2000)’s [1] model, indicating much higher profits when acceptance sampling is used.

Old, New or Digital Philology

BRILL eBooks, Apr 25, 2023

Humour in Islamic Literature and Muslim Practices: Virtue or Vice?

Policy Press eBooks, May 26, 2022

Humour in Islamic Literature and Muslim Practices

Bristol University Press eBooks, May 26, 2022

Chapter 2 The Making of a Qurʾān Manuscript in Lamu Archipelago: The Indian Ocean Cross-cultural Influence

Edinburgh University Press eBooks, Dec 31, 2023

4 Poems in Praise of the Prophet (madīḥ) as a Citizen of the Literary World

Edinburgh University Press eBooks, Nov 30, 2022

$Research paper thumbnail of The Knowledge Quarter: The British Library\u27s New Initiative of Partnership$

The Knowledge Quarter: The British Library\u27s New Initiative of Partnership

$Research paper thumbnail of The Sanaa Palimpsest: the transmission of the Qur\u27an in the first centuries (Book Review)$

The Sanaa Palimpsest: the transmission of the Qur\u27an in the first centuries (Book Review)

Beyond digitization: The case of The Aga Khan Library

Women's Activism and New Media in the Arab World by Ahmed Al-Rawi (review)

Information & Culture, 2022

برامج التعليم الببليوجرافي في المكتبات الأكاديمية ودورها في دعم البحث العلمي

مقامات الأولياء والصالحين في الواحات Saints and Sufi Shrines in an Egyptian Oasis (Dakhla)

Memory of Egypt Magazine (ذاكرة مصر), 2021

The Sanaa Palimpsest: the transmission of the Qur'an in the first centuries (Book Review)

<i>Islamic Calligraphy</i>, by Sheila Blair

Journal of Islamic Archaeology, 2018

Economic production quantity with maintenance interruptions under random and correlated yields

International Journal of Production Research, 2016

This paper considers an economic production quantity with imperfect items where the quality of it... more This paper considers an economic production quantity with imperfect items where the quality of items produced within the same production run is correlated. Production and scheduled maintenance policies for a correlated binomial production system are investigated. We study the impact of correlation on the system performance measures and draw insights in terms of the effect of correlation on the production and maintenance policies. We also illustrate that the popular and commonly used interrupted geometric production systems can be analysed by an equivalent correlated binomial production model.

An analytical approach to estimate the expected duration and variance for iterative product development projects

Research in Engineering Design, 2015

The paper presents an analytical method for finding the expected duration and variance of a produ... more The paper presents an analytical method for finding the expected duration and variance of a product development (PD) project network. A PD project network is a stochastic activity network (such as a PERT network) which allows for probabilistic repetition of activities (i.e., activity rework). When rework is allowed, estimating the process duration and variance becomes difficult. Most existing literature refers to the use of simulation in such scenarios; however, few analytical methods exist to solve this problem. One such method is called the reward Markov chain (RMC) which only considers sequential activity networks and which we use as a starting point in our proposed method. In this paper, we extend the RMC method to solve mixed networks (i.e., a combination of parallel and sequential activities) and more complicated practical issues that may arise in PD environments, specifically coupled activities and parallel rework.

Continuous (s, S) policy with MMPP correlated demand

European Journal of Operational Research, 2015

This work considers a continuous inventory replenishment system where demand is stochastic and de... more This work considers a continuous inventory replenishment system where demand is stochastic and dependent on the state of the environment. A Markov Modulated Poisson Process (MMPP) is utilized to model the demand process where the corresponding embedded Markov Chain represents the state of the environment. The equations to calculate the system inventory measures and the number of orders per unit time are obtained for a continuous, infinite horizon and dynamically changing (s, S) policy. An efficient optimization heuristic is presented and compared to the commonly used approach of approximating the demand-count process over the lead time with a Normal distribution. An investigation of the MMPP demand process is considered where we quantify the impact of variability in the demand-count process which is due to auto-correlation. Our findings indicate that when demand correlation is high, a dynamic control, where the (s, S) policy changes with state of the environment governing the MMPP, is highly superior to the commonly used “static” heuristics. We propose two dynamic policies of varying computational complexity, and cost efficiency, depending on the class of the product (one for class A, and one for classes B and C), to handle such high-correlation situations.

Effect of deterioration on the instantaneous replenishment model with imperfect quality items

Applied Mathematical Modelling, 2014

ABSTRACT The assumptions required to justify the use of the economic order quantity model (EOQ) a... more ABSTRACT The assumptions required to justify the use of the economic order quantity model (EOQ) are rarely met. To provide mathematical models that more closely represent real-life situations, these assumptions must be relaxed. Among these assumptions are, first, items stocked are of perfect quality, and second, they preserve their characteristics during their stay in inventory. This paper considers a modified EOQ-type inventory model for a deteriorating item with unreliable supply. That is, a percentage of the on-hand inventory is wasted due to deterioration. Moreover, orders may contain a random proportion of defective items, which follow a known distribution. As soon as an order is received, a retailer conducts a screening process to identify imperfect quality items, which are salvaged as a single batch at the end of the screening process. First, a mathematical model is developed, assuming that no shortages are allowed. For that, it is assumed that the inventory level when placing an order is just enough to cover the demand during the screening period. The concavity of the profit function is established and sensitivity analysis is provided to analyze the impact of changing various model parameters on the optimal order quantity and profit. Then, the assumption of no shortages is relaxed, and a model is developed to incorporate backorders. We analyze the model with backorders numerically and provide managerial insights.

Fitting the Pht/Mt/s/c Time-Dependent Departure Process for Use in Tandem Queueing Networks

INFORMS Journal on Computing, 2013

This paper considers time-dependent Pht/Mt/s/c queueing nodes and small tandem networks of such n... more This paper considers time-dependent Pht/Mt/s/c queueing nodes and small tandem networks of such nodes. We examine characteristics of the departure processes from a multiserver queueing node; in particular, we focus on solving for the first two time-dependent moments of the departure-count process. A finite set of partial moment differential equations is developed to numerically solve for the departure-count moments over specified intervals of time [ti, ti + τi). We also present a distribution fitting algorithm to match these key characteristics with a [Formula: see text] process serving as the approximate departure process. A distribution fitting algorithm is presented for time-dependent point processes where a two-level balanced mixture of Erlang distribution is used to serve as the approximating process. We then use the [Formula: see text] approximating departure process as the approximate composite arrival process to downstream node(s) in a network of tandem queues.

Transshipment and safety stock under stochastic supply interruption in a production system

Computers & Industrial Engineering, 2012

We consider a two-echelon system with one source supplying two locations with the same product. T... more We consider a two-echelon system with one source supplying two locations with the same product. The random occurrence of interruptions at the source where downtime is also stochastic can result in stockouts at the two receiving locations. Our model studies the benefit of allowing each location to carry a safety stock where holding costs can be different at each location. The objective is to reduce overall cost at both locations. In some cases it is optimal to allow for a transshipment of inventory from the safety stock of one location to the other. We jointly solve for the optimal safety stock at each location and the optimal amount to be transshipped from a location to the other. We show that by conditioning on the transshipment direction the total cost becomes convex as a function of the safety stock levels at the receiving locations and the amount to be transshipped from a location to the other. Numerical examples are presented for different system cost parameters and probability distributions.

An instantaneous replenishment model under the effect of a sampling policy for defective items

Applied Mathematical Modelling, 2013

ABSTRACT We propose to study a EOQ-type inventory model with unreliable supply, with each order c... more ABSTRACT We propose to study a EOQ-type inventory model with unreliable supply, with each order containing a random proportion of defective items. Every time an order is received, an acceptance sampling plan is applied to the lot, according to which only a sample is inspected instead of the whole lot. If the sample conforms to the standards, i.e. if the number of imperfect items is below an “acceptance number”, no further screening is performed. Otherwise, the lot is subject to 100% screening. We formulate an integer non-linear mathematical program that integrates inventory and quality decisions into a unified profit model, to jointly determine the optimal lot size and optimal sampling plan, characterized by a sample size, and an acceptance number. The optimal decisions are determined in a way to achieve a certain average outgoing quality limit (AOQL), which is the highest proportion of defective items in the outgoing material sold to customers. We provide a counter-example demonstrating that the expected profit function, objective of the mathematical program, is not jointly concave in the lot and sample size. However, we show that for a given sampling plan, the expected profit function is concave in the lot size. A solution procedure is presented to compute the optimal solution. Numerical analysis is provided to gain managerial insights by analyzing the impact of changing various model parameters on the optimal solution. We also show numerically that the optimal profit determined using this model is significantly higher when compared to the optimal profit obtained using Salameh and Jaber (2000)’s [1] model, indicating much higher profits when acceptance sampling is used.

A Female Court Historian Inside a Neo-Fatimid Treasury of Books

Nouvelles Chroniques du manuscrit au Yémen 17 (Ancienne série 36), 2023

[Book Reveiw] 2022. Olly Akkerman, A Neo-Fatimid Treasury of Books: Arabic Manuscripts among the ... more

‘Abd Al-Raḥmān b. ‘Amr Al-Awzāʿī [Book Review]

Manchester Journal of Transnational Islamic Law and Practice, 2020

On Taqlīd: Ibn al Qayyim's Critique of Authority in Islamic Law [Book Review]

Manchester Journal of Transnational Islamic Law and Practice, 2020

The Sanaa Palimpsest The Transmission of the Qurʾan

Uṣūl al-Tafsīr: The Sciences and Methodology of the Quran [Book review]

Computers for Libraries [Book Review]

Book review published in journal of ‘Alam al-Ma’lumat, 2001

Ethnographies of Islam: Ritual Performances and Everyday Practices, [Book review]

series is another research which adopts an ethnographic approach not only to show the strength an... more series is another research which adopts an ethnographic approach not only to show the strength and efficiency of this approach; but also to encourage and promote a pluralistic use of ethnography in research about Islam. Another aim of this book is to encourage ethnography in the study of Muslim practices that have been seldom been approached in this way.

مستقبل ضبط وإتاحة المخطوطات العربية

Bibliographic Databases of Arabic Manuscripts in some Egyptian Libraries : case study

Walid Ghali Nasr. Desscriptive Metadata for digitized Arabic manuscripts: an analytical study for four metadata schemas / Dr. Abd al-Sattar al-Halwagy; Dr. Mostafa Amin Hossam al-Din. Ph.D.

Report on the 3rd IFLA Meeting of Experts on International Cataloging Code, Dec.12-14 (2005 Cairo, Egypt)

Seminar on Islamic Studies Librarianship (Draft Report)

المخطوطات العربية كنوز في خطر

ISMC-IIS Joint Library : an introduction to the library collection

Constraints on manuscript digitization projects in Egypt

The objective of this paper is to categories the types of constraints that create obstacles for t... more The objective of this paper is to categories the types of constraints that create obstacles for the implementation of digitization projects in the Egyptian manuscript library. The paper will focus on one major constraint, which is related to the perception of the curators and managers of manuscript libraries towards the principles of digitization. The Central Library of Islamic Manuscripts, known as Awkaf Library, provides a clear example of these types of constraint, which have been encountered by the project team particularly at the early stages of the project. Two major cases will be presented in order to elaborate this issue: the first is the digitization of one of the most famous Koran manuscripts in the world, the one attributed to the third caliph Uthman ibn Affan (d. 35); and the second case concerns the manuscripts on magic or occult science.

Knowledge management in a challenging Middle East publishing setting – The role of Muslim Civilizations Abstracts (MCA) Project

The International Scientific Conference of Librarians Western Balkan Information and Media Literacy Conference 2019, 2019

This paper aims to shed light on a promising bibliographic project led by the Institute for the S... more This paper aims to shed light on a promising bibliographic project led by the Institute for the Study of Muslim Civilisations in London. The project aims at facilitating access to a wide range of literature in different languages related to various disciplines in Islamic and Middle Eastern studies. Although the project aims to tackle challenges relating to knowledge management in the Muslim world, the project itself faces many challenges including but not restricted to the setting of the publishing processes in the Middle East, readership statistics and the relationship between authors and publishers. The paper also will demonstrate the importance of bibliographical projects in the knowledge management cycle and its historical significance in Islamic studies.

State of manuscript digitization projects in some Egyptian libraries and their challenges

This chapter aims to shed light on the state of digitization projects that have been undertaken o... more This chapter aims to shed light on the state of digitization projects that have been undertaken or are in the planning stages in manuscript libraries in Egypt, specifically, the Egyptian National Library, where many different manuscripts projects have already taken place, Central Library of Islamic Manuscripts known as “Awqaf Library,” the Bibliotheca Alexandria, and the Library of al-Azhar, known as al-Azhar online project. The challenges faced by the respective projects teams will be discussed with a particular focus on the administrative and technical aspects. In addition, this chapter determines to what extent the infrastructure and the sufficient budgeting to implement a digitization projects is available.

Mashru' Istiqlal Misr 1883: min awraq al-Imam Muhammad Abdu al-Majhula

مشروع استثلال مصر 1883 , 2024

مشروع استقلال مصر 1883: من أوراق الإمام محمد عبده المجهولة

Understanding marc bibliographic translation into Arabic

Islamic and Middle East Area Studies Librarianship O C C A S I O N A L P A P E R N O . 3 J U N E 2 0 2 0

In this Series we publish progressive, innovative research to generate discussion and contribute ... more In this Series we publish progressive, innovative research to generate discussion and contribute to the advancement of knowledge. The papers represent work from affiliated faculty, fellows, researchers, and doctoral students across a wide range of research areas, demonstrating both the depth and breadth of research being undertaken at the Institute. We also offer the opportunity for our Masters students who have won the best thesis award to publish an abridged version of their thesis with us. We welcome submissions from external researchers that address current AKU-ISMC research priorities.

The Genre of Authorial Manuscripts in the Arabic Manuscripts Tradition Codicological observations