The purpose of this paper is to develop a new rectilinear branch pipe‐routing algorithm for automatic generation of rectilinear branch pipe routes in constrained spaces of…
Abstract
Purpose
The purpose of this paper is to develop a new rectilinear branch pipe‐routing algorithm for automatic generation of rectilinear branch pipe routes in constrained spaces of aero‐engines.
Design/methodology/approach
Rectilinear branch pipe routing that connects multiple terminals in a constrained space with obstacles can be formulated as a rectilinear Steiner minimum tree with obstacles (RSMTO) problem while meeting certain engineering rules, which has been proved to be an NP‐hard and discrete problem. This paper presents a discrete particle swarm optimization (PSO) algorithm for rectilinear branch pipe routing (DPSO‐RBPRA) problems, which adopts an attraction operator and an energy function to plan the shortest collision‐free connecting networks in a discrete graph space. Moreover, this paper integrates several existing techniques to evaluate particles for the RSMTO problem in discrete Manhattan spaces. Further, the DPSO‐RBPRA is extended to surface cases to adapt to requirements of routing pipes on the surfaces of aero‐engines.
Findings
Pipe routing numeral computations show that, DPSO‐RBPRA finds satisfactory connecting networks while considering several engineering rules, which demonstrates the effectiveness of the proposed method.
Originality/value
This paper applies the Steiner tree theory and develops a DPSO algorithm to plan the aero‐engine rectilinear branch pipe‐routing layouts.
Details
Keywords
Hakan Aygoren and Emrah Balkan
The aim of this study is to investigate the role of efficiency in capital asset pricing. The paper explores the impact of a four-factor model that involves an efficiency factor on…
Abstract
Purpose
The aim of this study is to investigate the role of efficiency in capital asset pricing. The paper explores the impact of a four-factor model that involves an efficiency factor on the returns of Nasdaq technology firms.
Design/methodology/approach
The paper relies on data of 147 firms from July 2007 to June 2017 to examine the impact of efficiency on stock returns. The performances of the capital asset pricing model (CAPM), Fama–French three-factor model and the proposed four-factor model are evaluated based on the time series regression method. The parameters such as the GRS F-statistic and adjusted R² are used to compare the relative performances of all models.
Findings
The results show that all factors of the models are found to be valid in asset pricing. Also, the paper provides evidence that the explanatory power of the proposed four-factor model outperforms the explanatory power of the CAPM and Fama–French three-factor model.
Originality/value
Unlike most asset pricing studies, this paper presents a new asset pricing model by adding the efficiency factor to the Fama–French three-factor model. It is documented that the efficiency factor increases the predictive ability of stock returns. Evidence implies that investors consider efficiency as one of the main factors in pricing their assets.
Details
Keywords
Muhammad Hanif, Abdullah Iqbal and Zulfiqar Shah
This study aims to understand and document the impact of market-based – market returns and momentum – as well as firm-specific – size, book-to-market (B/M) ratio…
Abstract
Purpose
This study aims to understand and document the impact of market-based – market returns and momentum – as well as firm-specific – size, book-to-market (B/M) ratio, price-to-earnings ratio (PER) and cash flow (CF) – factors on pricing of Shari’ah-compliant securities as explanation of variations in stock returns in an emerging market – Pakistan’s Karachi Stock Exchange.
Design/methodology/approach
Initially, the authors test Fama and French (FF) three-factor model – market risk premium, size and B/M – followed by modified FF model by including additional risk factors (PER, CF and momentum) over a 10-year period (2001-2010).
Findings
Our results support superiority of FF three-factor model over single-factor capital asset pricing model. However, addition of further risk factors – including PER, CF and momentum – improves explanatory power of the model, as well as refines the selection of risk factors. In this study, CF, B/M and momentum factors remain insignificant. Traditional B/M factor in FF model is replaced by PER.
Practical implications
Based on the modified FF model, the authors propose a stock valuation model for Shari’ah-compliant securities consisting of three factors: market returns, size and earnings, which explains 76per cent variations in cross sectional stock returns.
Originality/value
To the best of the authors’ knowledge, this is the first study (which combines market-based as well as fundamental factors) on pricing of Islamic securities and identification of risk factors in an emerging market – Karachi Stock Exchange.
Details
Keywords
Laurene Boateng, Eunice Nortey, Agartha N. Ohemeng, Matilda Asante and Matilda Steiner-Asiedu
Inadequacies in several micronutrients in complementary foods, notably iron, zinc, calcium, vitamin A, vitamin B6 and riboflavin have been reported. Moringa oleifera leaf powder…
Abstract
Purpose
Inadequacies in several micronutrients in complementary foods, notably iron, zinc, calcium, vitamin A, vitamin B6 and riboflavin have been reported. Moringa oleifera leaf powder (MLP), prepared from dried moringa leaves is nutrient-rich and has been explored for the treatment of micronutrient deficiencies among children in developing countries. This increasing interest in the use of moringa oleifera leaves to improve complementary foods notwithstanding, the unique sensory characteristics of the leaf powder potentially holds implications for the acceptability of local diets that are fortified with it. The purpose of this paper is to investigate the levels of MLP fortification that are most acceptable for feeding infants and young children.
Design/methodology/approach
The authors performed a review of the literature, with the aim of investigating the sensory attributes and acceptable levels of fortification of complementary food blends fortified with different levels of MLP.
Findings
The minimum amount of MLP to be added to a complementary food blend to observe significant improvements in its nutritional value was estimated to be about 10 per cent. However, at this 10 per cent fortification level also, sensory attributes of the products begin to become less desirable.
Practical implications
For the success of nutrition interventions that involve the use of MLP to improve the nutritional quality of complementary foods, there is a need to consider the acceptability of the sensory attributes of the formulated blends in the target group. Safety of MLP as an ingredient in infant foods must also be investigated.
Originality/value
The authors of this paper make recommendations for the use of MLP to fortify complementary foods to ensure its success as a food fortificant in nutrition interventions. The researchers are not aware of any published study that focuses on this subject.
Details
Keywords
Aldo Romano, Giuseppina Passiante and Valerio Elia
Using a sample of 29 virtual clusters, the paper examines new sources of clustering in the digital economy. The “virtual cluster” phenomenon highlights the most significant effect…
Abstract
Using a sample of 29 virtual clusters, the paper examines new sources of clustering in the digital economy. The “virtual cluster” phenomenon highlights the most significant effect of the development of the information and communication technologies in the business environment. A virtual cluster is conceived as an e‐business community, made up of customers, suppliers, distributors and commerce providers sharing digital and knowledge networks for collaboration and competition. The purpose of this paper is to set out the characteristics of a new competitive space, in which a strategic role is played by virtual processes among partners, and to review the traditional sources of clustering in the digital economy environment (Romano et al., 1999). More specifically, this paper attempts to show the emerging overlap between digital and knowledge networks, which generates a new competitive space within a new global‐virtual learning environment. Finally, assuming that traditional sources of clustering are generally identified in specialisation (based on a sophisticated division of labour) and geographic proximity, the paper discusses how the role of organisational proximity acts as a substitute for geographic proximity in supporting coordination and tacit knowledge exchange. As it emerges from the analysis of our cases, from a managerial point of view, organisational proximity may be achieved through the implementation of supply chain management (SCM) and customer relationship management (CRM) strategies. An earlier version of this paper was presented at the 23rd Institute of Small Business Affairs Annual Resource and Policy Conference in November 1999 in Leeds, UK.
Details
Keywords
Muhammad Al-Abdullah, Izzat Alsmadi, Ruwaida AlAbdullah and Bernie Farkas
The paper posits that a solution for businesses to use privacy-friendly data repositories for its customers’ data is to change from the traditional centralized repository to a…
Abstract
Purpose
The paper posits that a solution for businesses to use privacy-friendly data repositories for its customers’ data is to change from the traditional centralized repository to a trusted, decentralized data repository. Blockchain is a technology that provides such a data repository. However, the European Union’s General Data Protection Regulation (GDPR) assumed a centralized data repository, and it is commonly argued that blockchain technology is not usable. This paper aims to posit a framework for adopting a blockchain that follows the GDPR.
Design/methodology/approach
The paper uses the Levy and Ellis’ narrative review of literature methodology, which is based on constructivist theory posited by Lincoln and Guba. Using five information systems and computer science databases, the researchers searched for studies using the keywords GDPR and blockchain, using a forward and backward search technique. The search identified a corpus of 416 candidate studies, from which the researchers applied pre-established criteria to select 39 studies. The researchers mined this corpus for concepts, which they clustered into themes. Using the accepted computer science practice of privacy by design, the researchers combined the clustered themes into the paper’s posited framework.
Findings
The paper posits a framework that provides architectural tactics for designing a blockchain that follows GDPR to enhance privacy. The framework explicitly addresses the challenges of GDPR compliance using the unimagined decentralized storage of personal data. The framework addresses the blockchain–GDPR tension by establishing trust between a business and its customers vis-à-vis storing customers’ data. The trust is established through blockchain’s capability of providing the customer with private keys and control over their data, e.g. processing and access.
Research limitations/implications
The paper provides a framework that demonstrates that blockchain technology can be designed for use in GDPR compliant solutions. In using the framework, a blockchain-based solution provides the ability to audit and monitor privacy measures, demonstrates a legal justification for processing activities, incorporates a data privacy policy, provides a map for data processing and ensures security and privacy awareness among all actors. The research is limited to a focus on blockchain–GDPR compliance; however, future research is needed to investigate the use of the framework in specific domains.
Practical implications
The paper posits a framework that identifies the strategies and tactics necessary for GDPR compliance. Practitioners need to compliment the framework with rigorous privacy risk management, i.e. conducting a privacy risk analysis, identifying strategies and tactics to address such risks and preparing a privacy impact assessment that enhances accountability and transparency of a blockchain.
Originality/value
With the increasingly strategic use of data by businesses and the contravening growth of data privacy regulation, alternative technologies could provide businesses with a means to nurture trust with its customers regarding collected data. However, it is commonly assumed that the decentralized approach of blockchain technology cannot be applied to this business need. This paper posits a framework that enables a blockchain to be designed that follows the GDPR; thereby, providing an alternative for businesses to collect customers’ data while ensuring the customers’ trust.