12 research outputs found

    Motivational Factors for the Implementation of ISO-9001 in Construction Firms of Pakistan

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    Motivating public and private construction firms to implement various management systems in their firms is not a simple job. Especially in Pakistan, management system is a new practice, most of the construction firms are not aware about the benefits of management system and what will be achieved after the implementation of management system. The implementation of ISO 9001 Quality Management System (QMS) in the construction industry is a continuing development method, particularly in small construction firms. On the other hand, the awareness level and readiness level of construction industry firms in Pakistan is yet very low as associated to other countries of Asia and Europe where ISO 9001 initiated. The purpose current study is to determine most responsible factors which will motivate the public and private construction firms of Pakistan to adopt the QMS (ISO 9001). A questionnaire survey was conducted and a total of 337 out of 553 questionnaires were received from public and private construction firms of AZBAGIKHPUSI areas. The analysis results depict 3 significant factors, which will motivate construction firms of Pakistan to implement ISO 9001 are (1) to qualify for bidding (2) to improve quality management system of company (3) to reduce wastage. Hence, based on these results and findings, the construction companies require ISO 9001 certification system and registration with Pakistan Engineering Council (PEC) as a constitution passed for the construction firms then to qualify for the bidding

    Ambient backcom in beyond 5G NOMA networks: A multi-cell resource allocation framework

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    The research of Non-Orthogonal Multiple Access (NOMA) is extensively used to improve the capacity of networks beyond the fifth-generation. The recent merger of NOMA with ambient Backscatter Communication (BackCom), though opening new possibilities for massive connectivity, poses several challenges in dense wireless networks. One of such challenges is the performance degradation of ambient BackCom in multi-cell NOMA networks under the effect of inter-cell interference. Driven by providing an efficient solution to the issue, this article proposes a new resource allocation framework that uses a duality theory approach. Specifically, the sum rate of the multi-cell network with backscatter tags and NOMA user equipments is maximized by formulating a joint optimization problem. To find the efficient base station transmit power and backscatter reflection coefficient in each cell, the original problem is first divided into two subproblems, and then the closed form solution is derived. A comparison with the Orthogonal Multiple Access (OMA) ambient BackCom and pure NOMA transmission has been provided. Simulation results of the proposed NOMA ambient BackCom indicate a significant improvement over the OMA ambient BackCom and pure NOMA in terms of sum-rate gains

    To build corpus of Sindhi language

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    The present day state of Sindhi corpus construction is elaborated in detail in this paper. The issues like corpus acquisition, tokenization and preprocessing have been analyzed and discussed minutely for Sindhi corpus enhancement. Initial observations and results are included for letter unigram, bigram and trigram frequencies. There has been discussed the present status of Sindhi corpus in perspective of restriction and future work. Orthography and script were also explored in this paper with reference to corpus development. Basically the word corpus was used first time by German Scholar (Das Corpus). The plural of corpus is corpora, which is used for huge text data consists of millions and billions of text data. The task of Natural Language Processing was very challenging because there was the scarcity of resources for computational linguistics and research. Different text corpora have been made in different languages of different countries, after reviewing the corpora of different languages of various countries, we are trying to make the corpus for Sindhi language

    Machine learning-enabled MIMO-FBMC communication channel parameter estimation in IIoT: A distributed CS approach

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    Compressed Sensing (CS) is a Machine Learning (ML) method, which can be regarded as a single-layer unsupervised learning method. It mainly emphasizes the sparsity of the model. In this paper, we study an ML-based CS Channel Estimation (CE) method for wireless communications, which plays an important role in Industrial Internet of Things (IIoT) applications. For the sparse correlation between channels in Multiple Input Multiple Output Filter Bank MultiCarrier with Offset Quadrature Amplitude Modulation (MIMO-FBMC/OQAM) systems, a Distributed Compressed Sensing (DCS)-based CE approach is studied. A distributed sparse adaptive weak selection threshold method is proposed for CE. Firstly, the correlation between MIMO channels is utilized to represent a joint sparse model, and CE is transformed into a joint sparse signal reconstruction problem. Then, the number of correlation atoms for inner product operation is optimized by weak selection threshold, and sparse signal reconstruction is realized by sparse adaptation. The experiment results show that the proposed DCS-based method not only estimates the multipath channel components accurately but also achieves higher CE performance than classical Orthogonal Matching Pursuit (OMP) method and other traditional DCS methods in the time-frequency dual selective channels

    Ultrathin Graphene Oxide-Based Nanocomposite Membranes for Water Purification

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    Two-dimensional graphene oxide (GO)-based lamellar membranes have been widely developed for desalination, water purification, gas separation, and pervaporation. However, membranes with a well-organized multilayer structure and controlled pore size remain a challenge. Herein, an easy and efficient method is used to fabricate MoO2@GO and WO3@GO nanocomposite membranes with controlled structure and interlayer spacing. Such membranes show good separation for salt and heavy metal ions due to the intensive stacking interaction and electrostatic attraction. The as-prepared composite membranes showed high rejection rates (˃70%) toward small metal ions such as sodium (Na+) and magnesium (Mg2+) ions. In addition, both membranes also showed high rejection rates ˃99% for nickel (Ni2+) and lead (Pb2+) ions with good water permeability of 275 ± 10 L m−2 h−1 bar−1. We believe that our fabricated membranes will have a bright future in next generation desalination and water purification membranes

    Functionalized Graphene Oxide-Based Lamellar Membranes with Tunable Nanochannels for Ionic and Molecular Separation

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    Graphene oxide (GO)-based membranes with tunable microstructure and controlled nanochannels have attracted an increasing interest for various applications in wastewater treatment, desalination, gas separation, organic nanofiltration, etc. However, they showed limited use in water desalination due to their lower stability and separation efficiency. In this work, a class of two-dimensional (2D) GO lamellar membranes have been prepared with controlled pores for efficient and fast separation of ions and dye molecules. The GO membranes are fucntionalized with a star-like 6-armed poly(ethylene oxide) using the simple amidation route under mild conditions. The as-prepared covalently cross-linked networks are chemically steady in aqueous medium and show remarkable selectivity (similar to 100%) for several probe molecules and 10-100 higher permeance than those of the reported GO-based membranes. Further, such membranes are also used for salt separation and show more than 80% rejection for Pb2+ and Ni2+ salts. Moreover, a 1360 nm-thick membrane shows >99% rejection for NaCl with a good water permeance of up to 120 L m(-2) bar(-1). Additionally, these membranes are stable for more than 20 days under different conditions

    Functionalized Graphene Oxide-Based Lamellar Membranes with Tunable Nanochannels for Ionic and Molecular Separation

    No full text
    Graphene oxide (GO)-based membranes with tunable microstructure and controlled nanochannels have attracted an increasing interest for various applications in wastewater treatment, desalination, gas separation, organic nanofiltration, etc. However, they showed limited use in water desalination due to their lower stability and separation efficiency. In this work, a class of two-dimensional (2D) GO lamellar membranes have been prepared with controlled pores for efficient and fast separation of ions and dye molecules. The GO membranes are fucntionalized with a star-like 6-armed poly(ethylene oxide) using the simple amidation route under mild conditions. The as-prepared covalently cross-linked networks are chemically steady in aqueous medium and show remarkable selectivity (similar to 100%) for several probe molecules and 10-100 higher permeance than those of the reported GO-based membranes. Further, such membranes are also used for salt separation and show more than 80% rejection for Pb2+ and Ni2+ salts. Moreover, a 1360 nm-thick membrane shows >99% rejection for NaCl with a good water permeance of up to 120 L m(-2) bar(-1). Additionally, these membranes are stable for more than 20 days under different conditions

    Two-Dimensional Transition Metal Carbides and Nitrides (MXenes) for Water Purification and Antibacterial Applications

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    Two-dimensional (2D) materials such as graphene, graphene oxide (GO), metal carbides and nitrides (MXenes), transition metal dichalcogenides (TMDS), boron nitride (BN), and layered double hydroxide (LDH) metal–organic frameworks (MOFs) have been widely investigated as potential candidates in various separation applications because of their high mechanical strength, large surface area, ideal chemical and thermal stability, simplicity, ease of functionalization, environmental comparability, and good antibacterial performance. Recently, MXene as a new member of the 2D polymer family has attracted significant attention in water purification, desalination, gas separation, antibacterial, and antifouling applications. Herein, we review the most recent progress in the fabrication, preparation, and modification methods of MXene-based lamellar membranes with the emphasis on applications for water purification and desalination. Moreover, the antibacterial properties of MXene-based membranes show a significant potential for commercial use in water purification. Thus, this review provides a directional guide for future development in this emerging technology
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