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This paper aims to find ways to optimise the thermal performance of this courtyard design in current urban communities in hot arid regions.

The case study for this research is the Dubai sustainable city residential cluster. After collecting weather data from a site visit, four courtyard configurations were suggested and assessed using ENVI-met simulation analysis software to build a virtual model to represent the base case. This model is used to evaluate the thermal behaviour of outdoor urban spaces. The four courtyard layout scenarios were suggested and tested against the base case model. Scenario one is u-shaped, scenario two is linear, scenario three has central buildings with square courtyards and finally, scenario four has u-shaped buildings with square courtyards.

All the courtyard scenarios achieved an adequate level of user satisfaction, and the wind speed and distribution affected the relative humidity of the outdoor areas. The main findings indicate that courtyard scenario four provided the best microclimatic behaviour within the urban community, as the relative humidity dropped from 56.27% to 48% and the temperature was reduced from 43.03 °C to 41.03 °C.

The study was focused on Dubai and on urban levels, but the findings can be generalized to cover most of courtiers that have similar climatic and environmental contexts.

Architects and urban planners will recognize the potential to reduce energy due to natural ventilation and lower solar radiation.

If the findings be applied, this will lead to energy reduction as well as building foot print reduction.

This paper contributes to the existing literature by comprehensively reviewing the concept of courtyards in hot climate and in a region of shortage of studies conducted. It will draw future recommendations of how and where to design courtyards within urban communities.

The purpose of this study is to investigate the potential of implementing a toxicity tax for heavily polluting vehicles in United Arab Emirates. A fast-changing world needs responsive policies to cope with the crisis human beings are currently facing on earth. Implementing a new policy represents a design for a change. Policies come in the form of regulations that have been officially agreed and chosen by either a political party, business or any other type of organization. This paper adopts the policy development cycle in the Australian policy handbook as a practical framework. A focus group comprising 35 participants and two decision makers thoroughly discussed each stage of the “policy development cycle”. A qualitative analysis of the data showed that there is potential for implementing a new tax to be imposed on highly polluting vehicles in United Arab Emirates (UAE) the most appropriate policy instrument in UAE is a policy enacted through restricted law; it might take more than 3 years to work; the expected tax would range between $280 and $1,100 per year; and there is concern that this new tax would slow Dubai’s preparation for EXPO 2020. These findings will help countries implement this new tax. Following the stages of the policy development cycle and their procedures will, therefore, inspire decision makers to formulate new environmental policies not only in UAE but around the world.

This research adopts the use of “focus groups” as its primary approach to data collection. A focus group is a common qualitative research technique and involves a small number of participants. The main reason for using qualitative research is because participants are asked for open-ended responses that convey their thoughts or feelings. The author of this paper served as the moderator who posed a series of questions intended to gain insight into the group’s views on the implementation of a toxicity tax for heavy polluting vehicles in the UAE. Time and attention were given to what it is that you expect to get out of focus-group research. The group was invited for one full day to a big hall and was seated around one table. The group was sometimes divided to obtain more focused views. Overall, four primary groups participated in this study. A fifth group, consisting of three senior members of a governmental agency who acted as decision makers, took part in one-to-one interviews at their place of work. Table I provides details on the backgrounds of the participant.

Research highlights the policy development cycle to investigate a new transport policy in UAE. A focus group comprising 35 participants and two interviews with two decision makers. There is potential for a tax to be imposed on highly polluting vehicles in UAE. The expected tax would range between $280 and $1,100 per year. The best policy instrument in the region is policy by law. The truck industry will be affected, and there will be a public refusal.

A new policy of implementing tax for high polluting vehicles was, therefore, discussed in this paper. Participants thought the tax would work, but an in-depth feasibility study on both microeconomic and macroeconomic aspects will be required; providing governmental incentives will help support the shift to less-polluting vehicles.

The policy development cycle was utilized as a practical framework for this research.

People were engaged into this study to make the policy viable. People will react positively to this policy.

Due to the lack of such research in this area, this paper will fill a gap in the knowledge. Moreover, the policy will be real implementation based on this publication. The findings will not only help UAE but also many countries that share same environmental and social contexts.

The purpose of this paper is to study the inhibition effect of (6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) on the corrosion of mild steel in acidic medium by gravimetric measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS).

Weight loss measurements, potentiodynamic tests and EIS were performed during this study.

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to be a very efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 85 per cent with inhibitor concentration 1.0 × 10-3 M at 303 K.

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to play an important role in the corrosion inhibition of mild steel in acidic solution.

This paper is intended to be added to the family of pyridazine derivatives which are highly efficient inhibitors and can be used in the area of corrosion prevention and control.

The purpose of this study is to prepare new pigments derived from Red Lake C (RLC) to be applied in the inks industry and to identify their chemical nature, as well as their physical properties.

A number of pigments that could be applied in special printing were prepared via the reactions of RLC with appropriate Ni(II) and Zn(II) salts in aqueous and ethanolic solutions. The obtained pigments were prepared as solid compounds and characterized using different instrumental analysis such as Ultraviolet-Visible, Fourier Transform Infrared Spectroscopy, ¹H NMR spectra and magnetic measurements. The physical properties of these pigments were investigated using “American Standard Testing Methods” (ASTM). After that, the pigments were applied in ink formulations to test their performance and open the way to their real applications in the printing inks industry.

The results of this work revealed that the performance of the new prepared pigments is closer to the performance of the commercial pigments which are already used in ink industry.

Red lake C, as well as the new pigments, can be applied in other different industries such as coated papers, crayons, rubber and baking enamels.

The prepared pigments will be economically feasible and a good alternative to the original expensive commercial pigments which are already used in the inks industry.

The inhibition effect of Foeniculum vulgare seeds’ (FVS) extract on the corrosion of mild steel in acidic medium was studied using weight loss, electrochemical impedance spectroscopy and Tafel polarization, as well as the surface morphology of the mild steel.

Weight loss measurements, potentiodynamic tests, electrochemical impedance spectroscopy studies and gas chromatography/mass spectrometry and scanning electron microscopy analysis of FVS extract were performed.

FVS extract acts as a good inhibitor for the corrosion of mild steel in 1.0 M HCl. The inhibition efficiency increases with the increase in inhibitor concentration but decreases with the increase of temperature.

FVS extract was observed to play an important role in the corrosion inhibition of mild steel in acidic solution.

This paper is intended to be added to the family of green inhibitors which are highly efficient inhibitors and can be used in the area of corrosion prevention and control.

The effects of the addition of poly(4‐vinylpyridine) (P4VP) and its derivative poly(4‐vinylpyridine poly‐3‐oxide ethylene) (P4VPPOE) on the corrosion of Cu60‐Zn40 in 0.5M HNO₃ have been investigated by potentiodynamic and weight loss measurements. Both of the studied polymers decrease the corrosion rate. Their inhibition efficiency (E%) increases with the concentration. The maximum of inhibition was obtained for P4VPPOE (100 per cent at 10^–5M). E% obtained from cathodic Tafel plots and weight loss methods were in good agreement. The inhibitors were adsorbed on the Cu60‐Zn40 surface according to the Frumkin adsorption isotherm model. P4VPPOE acts as a cathodic inhibitor and its efficiency is temperature independent.

Integrating sustainability into the value management (VM) process can provide a strategic platform for promoting and incorporating sustainable design and development during the lifespans of construction projects. The purpose of this paper is to investigate the strengths, weaknesses, opportunities and threats (SWOT) for integrating sustainability into the VM process in Hong Kong.

Following an extensive literature review, 45 attributes were identified and grouped into strength, weakness, opportunity and threat elements. A questionnaire survey based on these groupings was supported by semi-structured interviews with public sector clients, value managers and VM facilitators. They shared their experience and views on how to integrate sustainability into the VM exercises.

The triangulated results of the survey and interviews are presented in this paper. The ranking of the SWOT analysis results indicate that VM does provide opportunities for multidisciplinary professionals and stakeholders to focus on issues relating to society and the environment, which is considered a main strength. The major weakness of integration is the lack of well-trained staff and low levels of VM participant expertise in relation to the sustainable construction issue.

Current practices generally neglect integration of sustainability into the VM process due to cost and time constraints. There are ample strengths and opportunities recommended by this study for integrating sustainability into the VM process which are beneficial for the clients and contractors for achieving value for money and meeting sustainability targets.

There are immense opportunities for integrating sustainability into the VM process, including encouragement of the reduction, reuse and recycling of construction and demolition waste. However, threats presented by integration include the additional time and costs required for achieving sustainability targets.

Findings and recommendations provided in this paper should be helpful to decision makers including clients and VM facilitators for the successful integration of the sustainability concept into the VM process.

Reverse supply chain (RSC) is an extension of the traditional supply chain (TSC) motivated by environmental requirements and economic incentives. TSC management deals with planning, executing, monitoring, and controlling a collection of organizations, activities, resources, people, technology, and information as the materials and products move from manufacturers to the consumers. Except for a short warranty period, TSC excludes most of the responsibilities toward the product beyond the point of sale. However, because of growing environmental awareness and regulations (e.g. product stewardship statute), TSC alone is no longer an adequate industrial practice. New regulations and public awareness have forced manufacturers to take responsibilities of products when they reach their end of lives. This has necessitated the creation of an infrastructure, known as RSC, which includes collection, transportation, and management of end-of-life products (EOLPs). The advantages of implementing RSC include the reduction in the use of virgin resources, the decrease in the materials sent to landfills and the cost savings stemming from the reuse of EOLPs, disassembled components, and recycled materials. TSC and RSC together represent a closed loop of materials flow. The whole system of organizations, activities, resources, people, technology, and information flowing in this closed loop is known as the closed-loop supply chain (CLSC).

In RSC, the management of EOLPs includes cleaning, disassembly, sorting, inspecting, and recovery or disposal. The recovery could take several forms depending on the condition of EOLPs, namely, product recovery (refurbishing, remanufacturing, repairing), component recovery (cannibalization), and material recovery (recycling). However, neither the quality nor the quantity of returning EOLPs is predictable. This unpredictable nature of RSC is what makes its management challenging and necessitates innovative management science solutions to control it.

In this chapter, we address the order-driven component and product recovery (ODCPR) problem for sensor-embedded products (SEPs) in an RSC. SEPs contain sensors and radio-frequency identification tags implanted in them at the time of their production to monitor their critical components throughout their lives. By facilitating data collection during product usage, these embedded sensors enable one to predict product/component failures and estimate the remaining life of components as the products reach their end of lives. In an ODCPR system, EOLPs are either cannibalized or refurbished. Refurbishment activities are carried out to meet the demand for products and may require reusable components. The purpose of cannibalization is to recover a limited number of reusable components for customers and internal use. Internal component demand stems from the component requirements in the refurbishment operation. It is assumed that the customers have specific remaining-life requirements on components and products. Therefore, the problem is to find the optimal subset and sequence of the EOLPs to cannibalize and refurbish so that (1) the remaining-life-based demands are satisfied while making sure that the necessary reusable components are extracted before attempting to refurbish an EOLP and (2) the total system cost is minimized. We show that the problem could be formulated as an integer nonlinear program. We then develop a hybrid genetic algorithm to solve the problem that is shown to provide excellent results. A numerical example is presented to illustrate the methodology.

Recently, there has been a shift toward the embodied energy assessment of buildings. However, the impact of material service life on the life-cycle embodied energy has received little attention. We aimed to address this knowledge gap, particularly in the context of the UAE and investigated the embodied energy associated with the use of concrete and other materials commonly used in residential buildings in the hot desert climate of the UAE.

Using input–output based hybrid analysis, we quantified the life-cycle embodied energy of a villa in the UAE with over 50 years of building life using the average, minimum, and maximum material service life values. Mathematical calculations were performed using MS Excel, and a detailed bill of quantities with >170 building materials and components of the villa were used for investigation.

For the base case, the initial embodied energy was 57% (7390.5 GJ), whereas the recurrent embodied energy was 43% (5,690 GJ) of the life-cycle embodied energy based on average material service life values. The proportion of the recurrent embodied energy with minimum material service life values was increased to 68% of the life-cycle embodied energy, while it dropped to 15% with maximum material service life values.

The findings provide new data to guide building construction in the UAE and show that recurrent embodied energy contributes significantly to life-cycle energy demand. Further, the study of material service life variations provides deeper insights into future building material specifications and management considerations for building maintenance.