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The simulations of grid-resolved rod vortex generators (RVGs) require high computational cost and time. Additionally, the computational mesh topology must be adjusted to rods geometries. The purpose of this study is to propose the new source term model for RVG.

The model was proposed by modification of Bender, Anderson, Yagle (BAY) model used to predict flows around different type of vortex generators (VGs) – vanes. Original BAY model was built on lifting line theory. The proposed model was implemented in ANSYS Fluent by means of the user-defined function technique. Additional momentum and energy sources are imposed to transport equations.

The computational results of source term model were validated against experimental data and numerical simulation results for grid-resolved rod. It was shown that modified BAY model can be successfully used for RVG in complex cases. An example of BAY model application for RVG on transonic V2C airfoil with strongly oscillating shock waves is presented. Aerodynamic performance predicted numerically by means of both approaches (grid resolved RVG and modeled) is in good agreement, what indicates application opportunity of the proposed model to complex cases.

Modified BAY model can be used to simulate the influence of RVGs in complex real cases. It allows for time/cost reduction if the location or distribution of RVG has to be optimized on a profile, wing or in the channel.

In the paper, the new modification of BAY model was proposed to simulate RVGs. The presented results are innovative because of original approach to model RVGs.

Demand for goods/services has increased in Latin America due to urbanization, leading to a complex delivery system and increased logistical activities. In Quito, the Historic Center and La Mariscal are two zones that face logistical challenges. The objective of this chapter is to analyze the commercial logistic activities related to loading and unloading goods in these zones. To address this urban freight problem, this chapter proposes a solution through the calculation of the optimal number and location of loading and unloading bays in each zone based on actual commercial activity data. First, a delivery survey was completed in each zone regarding frequency and amount of deliveries. Then, based on the data obtained, an optimization model is proposed to determine the optimal number and location of loading and unloading bays. Finally, a simulation model of the delivery process is performed to readjust the bay’s optimal number. A total number of 75 and 98 bays were calculated to serve the total shopping district of a representative square kilometer (km²) of the Historic Center and La Mariscal. This solution aims to minimize the delivery time and the distance for deliveries, improve urban freight transportation, and reduce traffic. This study could be used as a baseline and guide for further research in urban logistics, especially in Latin America, where urban logistics is still under study. This chapter is part of a Research Project of Urban Logistics in Quito, led by Universidad San Francisco de Quito (USFQ), in association with the Megacity Logistics Lab of MIT.

The purpose of this paper is to develop a new Islamic credit card model that is in line with Shariah principles and can be adopted as an alternative to contemporary Islamic credit card models by Islamic financial institutions in Malaysia.

This paper is theoretical in nature and mainly based on descriptive research method approach.

The overall findings indicate that the contemporary practice of Islamic credit card in Malaysia is still controversial in its design and operation. Moreover, the adoption and practice of Shariah contracts in bay’ al-inah, tawarruq and ujrah models are not in line with fundamental doctrines of Shariah and are imbued with the practice of hilah (legal trick), which allows them to circumvent the prohibition of riba. The paper indicates that Al-Muqassah model possibly has a comparative advantage in design and operation when compared with the bay’ al-inah, tawarruq or ujrah models.

The paper is limited to develop a new Shariah-compliant Islamic credit card model. The paper presents a design and defines the underlying Islamic financial contracts and their working mechanisms in the proposed model. However, it will not address other related areas like consumer perception, legal and regulatory requirements.

The paper will have direct implications on contemporary practice of Islamic credit card in Malaysia and elsewhere. The practice of Al-Muqassah model can also possibly have effects on common well-being and economic development.

The paper has relevance for Islamic financial institutions offering Islamic credit cards. The proposed model is fully in line with fundamental doctrines of Shariah and performs the key functions of an Islamic credit card.

The purpose of this paper is to address the case of toxic metal contamination of Sepetiba Bay caused by the Ingá Company. The paper reviews the history of the contamination and discusses the current presence of metals in the bay sediments, demonstrating that the toxic metals are clearly enriched. Sepetiba Bay is prone to significant dredging activities that make metals available in the food chain, affecting human populations, mainly fishermen communities.

The study presents the case of the Ingá Company based on international literature and data provided by previous studies.

Through the analysis and compilation of diverse data from the literature, this study demonstrates that the Ingá Company is a major source of Cd, Pb and Zn due to its calamine processing activities used to obtain high purity Zn.

This study highlights important research to complete the historical scenario of heavy metal contamination of the Sepetiba Bay by Ingá Company. The results indicate that the contaminants from the Ingá Company can indeed be traced in the sediments of Sepetiba Bay. These data have the utmost value for the environmental management of this coastal system, because such high concentrations of toxic metals in marine sediments have serious implications for the environmental quality of the bay and may negatively affect biota and human health. Therefore, this study suggests that it is now necessary to monitor this region for contamination continuously.

It is common practice in structural engineering to assume floor diaphragms infinitely stiff in their own plane. But, most of the code provisions lack clarity and unity in categorising floor diaphragms and discussing their behaviour based on the seismic response of the structures. Besides, although many of these code provisions have presented simple techniques and formulations for determining the level of flexibility in floor diaphragms, the implementation of these techniques on more complex floor systems such as the steel-deck composite floors is still under question. The paper aims to discuss these issues.

In this study, an equivalent concrete floor is employed as a representative of in-plane diaphragm action of steel-deck composite floor, using simple modelling techniques in SAP2000 and the results are validated by complex structural models developed in ABAQUS. Afterwards, the equivalent floor is inserted to 3, 5 and 7 storey steel structures with 2, 3 and 5 plan aspect ratios in two categories of structures with rigid diaphragms and analogous structures with flexible diaphragms and the responses are compared to each other.

The results show that the proposed technique is an effective method for evaluating the diaphragm action of steel-deck composite floors. Additionally, it is concluded that, the boundary values of plan aspect ratio equal to 3 and λ coefficient equal to 0.5 in steel-deck composite floors, mentioned in code provisions for categorising diaphragms, are not always conservative and need to be scrutinised.

The proposed methodology provides simple framework for assessing the effects of in-plane flexibility of steel-deck composite on seismic response of steel structures.

In structural health monitoring, localization of multiple slight damage without baseline data is significant and difficult. The purpose of this paper is to discuss these issues.

Damage in the structure causes singularities of displacement modes, which in turn reveals damage. Methods based on the displacement modes may fail to accurately locate the slight damage because the slight damage in engineering structure results in a relatively small variation of the displacement modes. In comparison with the displacement modes, the strain modes are more sensitive to the slight damage because the strain is the derivative of the displacement. As a result, the slight variation in displacement data will be magnified by the derivative, leading to a significant variation of the strain modes. A novel method based on strain modes is proposed for the purpose of accurately locating the multiple slight damage.

In the two bay beam and steel fixed-fixed beams, the numerical simulations and the experimental cases, respectively, illustrate that the proposed method can achieve more accurate localization in comparison with the one based on the displacement modes.

The paper offers a practical approach for more accurate localization of multiple slight damage without baseline data. And the robustness to measurement noise of the proposed method is evaluated for increasing levels of artificially added white Gaussian noise until its limit is reached, defining its range of practical applicability.

This study aims to examine the validity of the installment payment contract when using the first Islamic credit card (ICC) in Jordan and will explore the hidden techniques that are used to operate such a financial product. The purpose of the study will be achieved by examining the structure and the issues surrounding the first ICC that was introduced to the Jordanian market as a hybrid contract of Qard Hassan (benevolent loan), Murabaha, Wakalah (agency) and Bay‘ Al Ajjal (credit sale). In addition, a further objective is to examine whether this credit card is a Sharia-compliant financial product.

A qualitative research method approach was adopted to understand the issues, nature and structure of the first Jordanian ICC. This was due to the explanatory nature of the product, the different financial solutions it offered and the fact that the ICC in Jordan is, to date, relatively unexplored. This paper used the technique of content/thematic analysis that involves multiple sequenced steps to analyze these matters.

The main finding of this research is that the first ICC in the Jordanian financial market has caused a degree of uncertainty. This is because, once a customer decides to choose the installment payment contract option, the bank does not have real possession of the assets in question. The issue of constructive possession has been denied by several classic and contemporary Islamic scholars, including the General Iftaa Department of Jordan. Therefore, it can be seen that the installment payment contract option does not comply with Islamic principles and particular Fatwas that have been decreed.

This is the first study that shows how the first ICC, being a new Islamic financial product in Jordan, operates in relation to the installment payment contract. In addition, focusing on the concept of changing the nature of the contract from a Qard Hassan (benevolent loan) to a hybrid contract is significant, to encourage Islamic scholars to take a clear, legal stand under Sharia law.

It is known that people's expectation towards their living “green” is increasing. Green features are now regarded as one of the important considerations of buyers in purchasing a property. This research paper aims to investigate the significance of the green features of residential buildings to property buyers.

HK‐BEAM certification and HK‐GBC Award are used as the measurement of green residential buildings. The study used a hedonic price model to determine whether there is a relationship between green features and residential property price and the influence of green features on the residential property price if there is such relationship.

The empirical results show that green features have a significant and positive relationship with residential property price. People are willing to pay more for green buildings recognized by HK‐BEAM and HK‐GBC. They are willing to pay a sale price premium ranging from 3.4 percent to 6.4 percent. Furthermore, a relatively larger premium is found in Hong Kong Island compared to the New Territories.

The results imply that environmentally friendly green buildings both increase the value of a property and attract property buyers; and well‐recognized green building schemes add value to properties and hence increase the property price.

The study has contributed an indication of the amount a buyer would be willing to pay for quality green buildings as a reference for users, developers and investors. The study sheds light on the ability of the market to capitalize environmental considerations in investment decisions.

The purpose of this research is to identify how managers can apply the results of academic research into the concept of business models for creating and evaluating possible models for their businesses.

A review of the literature is followed by two case studies, from the airline and logistics industries, followed by recommendations based on both.

The findings are that there is relatively weak consensus among academics as to the definition and meaning of a business model and its components, and that the notion of generic business model applies better within rather than between industries, but that the discussion is a very fertile one for developing recommendations for managers.

The managerial implications of the study are that in their planning and strategizing, managers should factor in a proper analysis of the business model they currently use and one that they could use.

The study provides a useful addition to the literature on the practical implications of business models.

Vertical lift module (VLM) is a parts-to-picker system for order picking of small products, which are stored into two columns of trays served by a lifting crane. A dual-bay VLM order picking (dual-bay VLM-OP) system is a particular solution where the operator works in parallel with the crane, allowing higher throughput performance. The purpose of this paper is to define models for different operating configurations able to improve the total throughput of the dual-bay VLM-OP system.

Analytical models are developed to estimate the throughput of a dual-bay VLM-OP. A deep evaluation has been carried out, considering different storage assignment policies and the sequencing retrieval of trays.

A more accurate estimation of the throughput is demonstrated, compared to the application of previous models. Some use guidelines for practitioners and academics are derived from the analysis based on real data.

Differing from previous contributions, these models include the acceleration/deceleration of the crane and the probability of storage and retrieve of each single tray. This permits to apply these models to different storage assignment policies and to suggest when these policies can be profitably applied. They can also model the sequencing retrieval of trays.