Polarisation insensitive multifunctional metasurfaces based on all-dielectric nanowaveguides

Mahmood, Nasir,Kim, Inki,Mehmood, Muhammad Qasim,Jeong, Heonyeong,Akbar, Ali,Lee, Dasol,Saleem, Murtaza,Zubair, Muhammad,Anwar, Muhammad Sabieh,Tahir, Farooq Ahmad,Rho, Junsuk The Royal Society of Chemistry 2018 Nanoscale Vol.10 No.38

<P>Metasurfaces, two dimensional (2D) metamaterials comprised of subwavelength features, can be used to tailor the amplitude, phase and polarisation of an incident electromagnetic wave propagating at an interface. Though many novel metasurfaces have been explored, the hunt for cost-effective, highly efficient, low-loss and polarisation insensitive applications is ongoing. In this work, we utilise an efficient and cost-effective dielectric material, hydrogenated amorphous silicon (a-Si:H), to create a ultra-thin transmissive surface that simultaneously controls phase. This material exhibits significantly lower absorption in the visible regime compared to standard amorphous silicon, making it an ideal candidate for various on-chip applications. Our proposed design, which works on the principle of index waveguiding, integrates two distinct phase profiles, that of a lens and of a helical beam, and is versatile due to its polarisation-insensitivity. We show how this metasurface can lead to highly concentrated optical vortices in the visible domain, whose focused ring-shaped profiles carry orbital angular momentum at the miniaturised scale.</P>

The role of nuclear energy in the correction of environmental pollution: Evidence from Pakistan

Mahmood, Nasir,Danish, Danish,Wang, Zhaohua,Zhang, Bin Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.6

The global warming phenomenon emerges from the issue of climate change, which attracts the attention of intellectuals towards clean energy sources from dirty energy sources. Among clean sources, nuclear energy is getting immense attention among policymakers. However, the role of nuclear energy in pollution emissions reduction has remained inconclusive and demand for further investigation. Therefore, the current study contributes to extend knowledge by investigating the nexus between nuclear energy, economic growth, and CO₂ emissions in a developing country context such as Pakistan for the period between 1973 and 2017. The auto-regressive distributive lag model summarizes the nuclear energy has negative effect on environmental pollution as it releases carbon emission in the environment. Moreover, vector error correction Granger causality provides evidence for bidirectional causality between nuclear energy and carbon emissions. These interesting findings provide new insight, and policy guidelines provided based on these results.

Twisted non-diffracting beams through all dielectric meta-axicons

Mahmood, Nasir,Jeong, Heonyeong,Kim, Inki,Mehmood, Muhammad Qasim,Zubair, Muhammad,Akbar, Ali,Saleem, Murtaza,Anwar, Muhammad Sabieh,Tahir, Farooq Ahmad,Rho, Junsuk The Royal Society of Chemistry 2019 Nanoscale Vol.11 No.43

<P>We demonstrate transmission-based all-dielectric, highly efficient (≈73.4%) and polarization-insensitive meta-axicons (for the visible wavelength of 633 nm) to generate zero and higher order Bessel beams without using additional components. The Bessel beams, owing to their diverse applications and non-diffractive properties, attract great interest from the scientific community. It is shown that the propagation length can be increased through a lower numerical aperture (∼2600 <I>λ</I> for NA = 0.1) whereas a higher full width at half maximum (< 0.5 <I>λ</I>) can be obtained for a higher numerical aperture (for NA ≥ 0.7). Our dielectric material, hydrogenated amorphous silicon (a-Si:H), provides a significant efficiency advantage over plasmonic and other high-index all-dielectric (<I>e.g.</I>, TiO2 and GaN) metasurfaces in terms of cost, ease of fabrication, and CMOS compatibility. The finite difference time domain (FDTD) technique based numerically simulated and experimental results show excellent agreement. Due to the technological and scientific importance of the Bessel beams, the recommended material and meta-axicons provide an efficient and compact platform for realizing various advanced applications like optical manipulation, optical alignment, laser fabrication, imaging, and laser machining.</P>

Business Incubators: Boon or Boondoggle for SMEs and Economic Development of Pakistan

Nasir Mahmood,Cai Jianfeng,Farhan Jamil,Jawad Karmat,Mustafa Khan,Yue Cai 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.4

In this age of technological development, business incubation system is an important tool, for the government to implement and facilitate technological innovation and entrepreneurship development. An effective business incubation system renders an important role in the nourishment of local, national and regional economies by producing employment opportunities & development of SMEs. This study presents evidence that suggests business incubators are important for economic development especially for developing countries like Pakistan. A comprehensive survey was carried out to analyze the current functional status of business incubators, along with the services provided by those incubators, with their success & shortcoming links with incubation system in Pakistan. The importance of business incubators for the promotion of entrepreneurship, development and technological innovation, addressed with an assessment of the needs of Pakistan economy. This is followed with an evaluation of the requirements to be dealt before incubators can leave the desired effects on the improvements of the entrepreneurship and technological innovation. Finally, the findings reveal implications for the future development programme of business incubators in Pakistan with the policy recommendation.

The Role of University-Based Incubators in Developing Economies: Empirical Evidence from Pakistan

Nasir Mahmood,Cai Jianfeng,Hina Munir,Farhan Jamil,Anum Nusrat 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.11

Business incubators are an attractive tool for the economic development and support to nascent business in critical stages of their business life cycle. UBIs have a main featured to facilitate business tangible & intangible services such as access to research labs, office and network pool of different firms to build up nascent business. The aim of this paper, define the important role of UBIs have ability to support developing economies by providing talent from inside the university. UBIs also generate new resources and opportunities for innovation of products, creation of employment and leadership that play a key role in developing economies. In this paper the questionnaire survey used to know about the detailed information about the UBI. The results of this study give help to decision makers in university, industry and government for the growth of economy.

Snapshot of Technology Business Incubators in China

Nasir Mahmood,Cai Jianfeng,Farhan Jamil,Hina Munir,Jintao LU,Mustafa Khan,Yue Cai 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.7

In the contemporary world, the production of suitable goods and commodities and business developments, the business technology incubators are considered important for the inception of new ideas and combining them with the available resources. Similarly, business and technology incubators are considered a backbone to accelerate the innovation and new business development structure of national economies. The business incubators in China are flourishing by leaps and bounds since the mid of 1990s. This paper aims to explore the performance of technology business incubator in china. In this study the incubator data which was compiled by Ministry of Science and Technology (MOST) China was taken for performance evaluation in china. The performance of incubator in 2002 and in 2012 was assessed by comparison of total number of tenants, total income of tenants, number of graduated tenants and number of employees of tenants, further, in 2012 the association of number of invention patent with the accumulated number of tenants obtained investment and finance is assessed, and this paper also presents the graduated firms number every year in China. These results show that the performance of technology incubators is increased during the last decade.

Impact of Factors that Inhibit the Drive of Entrepreneurship in Pakistan: Empirical Evidence from Young Entrepreneurs and Students

Nasir Mahmood,Cai Jianfeng,Hina Munir,Nosheena Yasir 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.12

Nowadays, in the era of competitiveness, competition, innovation and development of a country cannot be achieved without the successful entrepreneurial process. The current research is intended to elaborate the factors that obstruct the drive of entrepreneurship in Pakistan. For this purpose a quantitative survey was conducted in order to examine the six factors: lack of education and skills, terrorism, social status, political environment, lack of financial resources and business environment with motivation of entrepreneurship. Data was collected through questionnaire using simple random sampling technique from the young businessmen and students from the 3 cities of Pakistan which includes Lahore, Gujranwala and Islamabad. For the purpose of the analysis the sample of 250 were selected out of which 200 questionnaires which show the response rate is 80%. Analysis was run by using SPSS 19 and results showed that the factors including lack of education and skills, terrorism, social status, political environment, lack of financial resources and business environment have significant relation with the motivation of entrepreneurship in Pakistan. The current study has provided valuable information and recommendation to government, financial institutions, socialists and potential entrepreneurs to improve the culture of entrepreneurship in Pakistan.

Incubators, SMEs, and Economic Development of China

Nasir Mahmood,Cai Jianfeng,Hina Munir,Ma Yanran,Yue Cai 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.1

In this rapidly growing and competitive technological development world, business incubation is a very supportive and productive tool for promoting the entrepreneurial environment, job creation and economic development. The efficacy of incubators is a crucial aspect for boosting the speed of local, regional and national economies and SMEs development. This study argues to suggest that efficiency of business incubators is vital for actively contributing in economic development especially for developing countries, namely China. A document analysis and archives based survey was conducted to review and analyse the practices of business incubators, as well as their strengths and weaknesses. Finally, the findings of the study reveal some future directions of business incubators in China with policy recommendations.

Unorthodox Approach to Classify EEG Signals for Upper Limb Prosthesis Application

Nasir Rashid,Fahad Mahmood,Javaid Iqbal 제어로봇시스템학회 2018 제어로봇시스템학회 국제학술대회 논문집 Vol.2018 No.10

Brain computer interface (BCI) is targeted for decoding the EEG (Electroencephalogram) signals that the human brain generates which are beneficial for the paraplegic patients. These EEG signals are slow cortical potentials that are directly recorded from scalp thus cortical neuronal activity is explored via non-invasive electrodes. These EEG signals are then further utilized for performing various operations which the paraplegic patients are unable to perform. This research article presents a novel architecture of classification of four finger movements (thumb movement, index finger movement, middle and index finger combined movement and fist movement) of the right hand on the basis of EEG (Electroencephalogram) data of the movements. The presented architecture utilizes Guided filter for reduction of noise (artefacts) from EEG signals alpha and beta band (8-30 Hz). As this band contains the maximum information of movement in terms of motor imagery. Rank Transform is employed as feature extraction approach for further enhancement of processed EEG signals. Two stage Logistic Regression classifier is finally employed for classification of movements using processed EEG signals. The experimental results demonstrate the accuracy, robustness and computational complexity of the proposed approach and have significant improvement as compared with recent architectures for EEG classification.

Enhancement of thermoelectric properties of MBE grown un-doped ZnO by thermal annealing

Khalid, Mahmood,Asghar, Muhammad,Ali, Adnan,Ajaz-Un-Nabi, M.,Arshad, M. Imran,Amin, Nasir,Hasan, M.A. Techno-Press 2015 Advances in energy research Vol.3 No.2

In this paper, we have reported an enhancement in thermoelectric properties of un-doped zinc oxide (ZnO) grown by molecular beam epitaxy (MBE) on silicon (001) substrate by annealing treatment. The grown ZnO thin films were annealed in oxygen environment at $500^{\circ}C-800^{\circ}C$, keeping a step of $100^{\circ}C$ for one hour. Room temperature Seekbeck measurements showed that Seebeck coefficient and power factor increased from 222 to $510{\mu}V/K$ and $8.8{\times}10^{-6}$ to $2.6{\times}10^{-4}Wm^{-1}K^{-2}$ as annealing temperature increased from 500 to $800^{\circ}C$ respectively. This observation was related with the improvement of crystal structure of grown films with annealing temperature. X-ray diffraction (XRD) results demonstrated that full width half maximum (FWHM) of ZnO (002) plane decreased and crystalline size increased as the annealing temperature increased. Photoluminescence study revealed that the intensity of band edge emission increased and defect emission decreased as annealing temperature increased because the density of oxygen vacancy related donor defects decreased with annealing temperature. This argument was further justified by the Hall measurements which showed a decreasing trend of carrier concentration with annealing temperature.