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The purpose of this paper is to investigate the structural, electronic and optical properties of pure zinc oxide (ZnO) and transition metal (Tm)-doped ZnO using Tm elements from silver (Ag) and copper (Cu) by a first-principles study based on density functional theory (DFT) as implemented in the pseudo-potential plane wave in CASTEP computer code.

The calculations based on the generalized gradient approximation for Perdew-Burke-Ernzerhof for solids with Hubbard U (GGA-PBEsol+U) were performed by applying Hubbard corrections U_d = 5 eV for Zn 3d state, U_p = 9 eV for O 2p state, U_d = 6 eV for Ag 4d state and U_d = 9.5 eV for Cu 3d state. The crystal structure used in this calculation was hexagonal wurtzite ZnO with a space group of P63mc and supercell 2 × 2 × 2.

The total energy was calculated to determine the best position for Ag and Cu dopants. The band structures and density of states show that Tm-doped ZnO has a lower bandgaps value than pure ZnO because of impurity energy levels from Ag 4d and Cu 3d states. In addition, Ag-doped ZnO exhibits a remarkable enhancement in visible light absorption over pure ZnO and Cu-doped ZnO because of its lower energy region and extended wavelength spectrum.

The results of this paper are important for the basic understanding of the 3d and 4d Tm doping effect ZnO and have a wide range of applications in designing high-efficiency energy harvesting solar cells.

Housing has always been a significant aspiration of family expression and distinctly priciest investment by household. It plays a momentous role in the country's economy and so central to the societal well-being that is emplaced in the United Nation Universal declaration of Human rights. Yet in developed and developing world alike, cities struggle to provide decent housing for lower and middle income population. The provision of affordable housing is a major policy concern around the world with Malaysia being no exception; rising income hardly keep pace with price hike of housing unit and housing interventions has majorly concentrated on demand side leading to a non-responsive supply sector. Therefore, this paper highlights affordable housing issues pertaining Malaysia. It formulates Malaysian Map of affordability and conducts an evaluation of global housing schemes to better identify policy priorities for Malaysia. It's significant to harmonize supply and demand side factors in the housing market to ensure that housing supply fits the needs of citizens based on the location, price and target group. In case of Malaysia supply oriented initiative are of urgency in short and medium run. This must be supported by long term demand side schemes in parallel. Convergence of these two factors is essential for a balanced equilibrium and obtaining affordability.

This study aims to examine the issues and challenges in contemporary affordable public housing schemes and proposes an alternative affordable public housing model for low- and middle-income households in Malaysia.

The paper applied qualitative research method. Semi-structured in-depth interviews with four government officials were conducted to understand the provision, framework and working mechanism of selected affordable public housing schemes. A focus group with nine participants was conducted with low- and middle-income households to validate pertaining residential issues and problems in affordable public housing schemes.

The overall findings reveal that the growing plights of unaffordability, poor maintenance and mismanagement have undermined the performance of affordable public housing schemes in Malaysia. The paper indicates that Islamic Public–Private Housing Co-operative Model (IPHCM) possibly has a comparative advantage in its design and operation and therefore can be implemented as an alternative model to address these issues in contemporary affordable public housing schemes in Malaysia. The findings also offer guidelines to government officials and managers of public housing schemes to implement the IPHCM model that can help in reducing the financial burden on low- and middle-income households, improving maintenance work and enforcing effective management practices with residents’ participation.

The paper is limited to develop a new Shariah-compliant affordable public housing model. The paper presents a design and defines the underlying Shariah concept and contracts and their working mechanisms in the proposed model. The paper has not considered other related areas in the development of IPHCM model including Shariah and subject matter expert’s perspective, consumer behavioural intention, legal and regulatory requirements.

The paper has relevance for policymakers and government institutions offering affordable public housing schemes to ensure successful deliverability of sustainable and affordable public housing for low- and middle-income households in Malaysia.

The purpose of this paper is to enhance the efficiency of the LED by introducing three-step magnesium (Mg) doping profile. Attention was paid to the effects of the Mg doping concentration of the first p-GaN layer (i.e. layer close to the active region). Attention was paid to the effects of the Mg doping concentration of the first p-GaN layer (i.e. layer close to the active region).

Indium gallium nitride (InGaN)–based light-emitting diode (LED) was grown on a 4-inch c-plane patterned sapphire substrate using metal organic chemical vapor deposition. The Cp₂Mg flow rates for the second and third p-GaN layers were set at 50 sccm and 325 sccm, respectively. For the first p-GaN layer, the Cp₂Mg flow rate varied from 150 sccm to 300 sccm to achieve different Mg dopant concentrations.

The full width at half maximum (FWHM) for the GaN (102) plane increases with increasing Cp₂Mg flow rate. FWHM for the sample with 150, 250 and 300 sccm Cp₂Mg flow rates was 233 arcsec, 236 arcsec and 245 arcsec, respectively. This result indicates that the edge and mixed dislocations in the p-GaN layer were increased with increasing Cp₂Mg flow rate. Atomic force microscopy (AFM) results reveal that the sample grown with 300 sccm exhibits the highest surface roughness, followed by 150 sccm and 250 sccm. The surface roughness of these samples is 2.40 nm, 2.12 nm and 2.08 nm, respectively. Simultaneously, the photoluminescence (PL) spectrum of the 250 sccm sample shows the highest band edge intensity over the yellow band ratio compared to that of other samples. The light output power measurements found that the sample with 250 sccm exhibits high output power because of sufficient hole injection toward the active region.

Through this study, the three steps of the Mg profile on the p-GaN layer were proposed to show high-efficiency InGaN-based LED. The optimal Mg concentration was studied on the first p-GaN layer (i.e. layer close to active region) to improve the LED performance by varying the Cp₂Mg flow rate. This finding was in line with the result of PL and AFM results when the samples with 250 sccm have the highest Mg acceptor and good surface quality of the p-GaN layer. It can be deduced that the first p-GaN layer doping has a significant effect on the crystalline quality, surface roughness and light emission properties of the LED epi structure.

This study aims to investigate the effects of indium composition on surface morphology and optical properties of indium gallium nitride on gallium nitride (InGaN/GaN) heterostructures.

The InGaN/GaN heterostructures were grown on flat sapphire substrates using a metal-organic chemical vapour deposition reactor with a trimethylindium flow rate of 368  sccm. The indium composition of the InGaN epilayers was controlled by applying different substrate temperatures. The surface morphology and topography were observed using field emission scanning electron microscope (F.E.I. Nova NanoSEM 450) and atomic force microscopy (Bruker Dimension Edge) with a scanning area of 10 µm × 10 µm, respectively. The compositional analysis was done by Energy Dispersive X-Ray Analysis. Finally, the ultraviolet-visible (UV-Vis) spectrophotometer (Agilent Technology Cary Series UV-Vis-near-infrared spectrometer) was measured from 200 nm to 1500 nm to investigate the optical properties of the samples.

The InGaN/GaN thin films have been successfully grown at three different substrate temperatures. The indium composition reduced as the temperature increased. At 760 C, the highest indium composition was obtained, 21.17%. This result was acquired from the simulation fitting of ω−2θ scan on (0002) plane using LEPTOS software by Bruker D8 Discover. The InGaN/GaN shows significantly different surface morphologies and topographies as the indium composition increases. The thickness of InGaN epilayers of the structure was ∼300 nm estimated from the field emission scanning electron microscopy. The energy bandgap of the InGaN was 2.54 eV – 2.79 eV measured by UV-Vis measurements.

It can be seen from this work that changes in substrate temperature can affect the indium composition. From all the results obtained, this work can be helpful towards efficiency improvement in solar cell applications.

The purpose of this paper is to look at the relationships among factors which result in improved knowledge sharing, through the empirical validation of a theoretical model consisting of three dimensions: expected benefit in relation to knowledge sharing, trust at workplace, and employee knowledge‐sharing behavior.

This study targets three technological companies with a total of employees exceeding 1,500 (n=563), utilizing a survey questionnaire as the data collection instrument to test the relationship among the three dimensions. The structural equation modeling approach is used to test the proposed model.

The results show that trust at workplace has a mediating effect on organizational knowledge‐sharing behavior. It is also discovered that there is significant correlation between expected personal benefit through sharing knowledge and the development of trust at workplace.

This study contributes empirical data to the predominantly theoretical literature by offering a deeper understanding of the mediating effect of trust on employee's expected benefit for the purpose of knowledge exchange behavior within teams and among teams.

Construction projects in the oil and gas sector are greatly affected by external risk factors, especially those related to the economy, politics, security and stability factors. Hence, this research aimed to investigate the fundamental relationship between the external risk factors and their effects on the construction project success using Structural Equation Modeling method and PLS-SEM approach.

Data collected through a structured survey distributed to projects teams in the oil and gas sectors in Yemeni companies involved in mega construction projects. A hierarchical model for assessing causative external risk factors and their effects on project success was developed and analyzed using Smart PLS 3 software of SEM.

The findings showed that economic, political, force majeure and security-related risk factors had a strong effect on project success. Besides, the Coefficient of Determination (R-squared value) equals 0.743, represented the proportion of variation in the dependent variable(s), which can be explained by one or more predictor variable. Moreover, the predictive relevance value Q2 is 0.375 above zero, which indicates that the conceptual model can predict the endogenous latent constructs. The calculated Goodness of Fit (GoF) Index of the model was 0.699, which shows that the developed model had substantial explanatory power to represent the relationship between the cause of external risk factors to and the effect on construction project success.

This research was limited to the oil and gas construction projects in Yemen as case study.

Practically, this study highlights the external risk factors that cause a negative effect on the success of oil and gas construction projects in Yemen. The research model of these factors is the first step in the risk management process to develop strategic responses for risks and explain the relationship between cause and effect on project success.

The model of external risks factors that cause the failure of construction projects helps develop response strategies for these risks, thereby increasing the chances of project success reflected in the oil and gas sector, which is a main tributary of the national economy in developing countries.

There is a need to improve the planning of economic and security performance as well as to mitigate political risk factors effects on project success and other risk factors discussed in this study, which effect on construction project success according to their priorities.

This study aims to identify the operational and financial risks associated with the city gas distribution project in India and suggest appropriate strategies to mitigate them.

This study aims to identify the operational and financial risks associated with the city gas distribution project in India and suggest appropriate strategies to mitigate them. The survey data is evaluated using factor analysis to understand the latent structure of the critical risk factors. Second, the author uses Situation, Actor and Process–Learning, Action and Performance framework to suggest the mitigation strategies for the identified operational and financial risk factors.

The research identified five critical risk factors and suggested 39 mitigation strategies to address operational and risk factors impacting CGD projects. The findings of this research will enable the CGD companies to formulate long-term strategies for their business and adopt proactive measures to mitigate the operational and financial risks causing delay and increasing project costs. This study also highlights the importance of government support in developing a conducive environment for CGD industry to thrive.

The CGD projects are critical for natural gas growth in India’s energy mix. The project delay leads to a rise in the total cost involved and increases the payback period for the CGD companies. To the best of authors’ knowledge, this research is first of its kind that identifies the critical operational and financial risks affecting CGD projects in India and suggests the mitigating strategies for them.

The study aims to report empirical evidence on the impact of mandatory adoption of International Financial Reporting Standards (IFRS) in India on the voluntary intellectual capital reporting (ICR) and its value relevance. The study also tests the effect of term-weighting schemes used for information retrieval studies in the domain area of ICR.

The study uses computational linguistics tools to measure ICR by Indian firms in the period 2014–2019. The study developed term frequencies for 23 ICR attributes using bag-of-words methodology from the annual reports. The word counts were used to construct two distinct measures of ICR, quantity and quality, deploying different term-weighting schemes, equal weighting and the term frequency-inverted document frequency (TF-IDF) weighting, respectively. A combination of parametric and non-parametric tests has been employed to examine the different hypothesis.

The quantity of ICR was found to have increased post-IFRS adoption. However, the quality of ICR had fallen significantly, which resulted in the loss of value relevance of ICR. Firms making higher disclosures but of inferior quality experienced suboptimal market returns. Variation in inter-firm ICR has reduced. Size effect and sector effect continue but have attenuated. The study acknowledges the enormous impact of term-weighting schemes, used for information retrieval studies, in the domain area of ICR.

The study strongly adds to the momentum in favour of a formal ICR standard to improve its quality, restore its value relevance and facilitate more effective decision-making where the valuation of a firm is a critical input. The study presages the firms not to make poor-quality disclosures to avoid suboptimal stock performance.

The study sheds light on the impact of the adoption of post-IFRS on ICR in India. The study establishes the effect of term-weighting schemes, used for linguistic studies, in the domain area of ICR and adds to the literature by explaining one of the critical reasons for the dichotomy in ICR trends.

The objective of this study is to investigate the factors of two sub-processes – knowledge donating and knowledge collecting – of knowledge sharing in Hong Kong higher education context. This study examines the individual factors, organizational factors and technology factor of knowledge sharing. Individual factors include enjoyment in helping others and knowledge self-efficacy while organizational factors refer to the top management support, organizational rewards and organizational culture. The use of technology system is proposed to be the technology factor.

Based on the literature review, this study develops a structural model representing the impact of six latent variables on knowledge donating and knowledge collecting processes Data from a questionnaire survey of 166 respondents from academics from Hong Kong higher education sector was used to analyze the model. PLS-SEM was adopted in this study.

The result of the data analysis suggests enjoyment in helping others has a positive impact on both knowledge donating and knowledge collecting. For organizational factors, a trust and collaborative culture enhance both the sub-processes. The technology factor only contributes to the knowledge donating process. Several practical implications are provided to high education leaders, for instance, by establishing a trust and collaborative environment, academics are more eager to donate and collect knowledge.

This paper provides insights for researchers to further understand how individual, organizational and technology factors affect two sub-processes of knowledge sharing. On the practical side, this study validated several critical factors to successful knowledge donation and knowledge collection.