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      • SCOPUS

        The Role of Small and Medium Enterprises in Achieving Economic Goals of the Vision of Saudi Arabia 2030

        Mohammed Ali Mohamed Ahmed ALI(Mohammed Ali Mohamed Ahmed ALI ),Ahmed Saied Rahama ABDALLAH(Ahmed Saied Rahama ABDALLAH ),SalimAhmed Mohamed AlSHEHRI(SalimAhmed Mohamed AlSHEHRI ) 한국유통과학회 2023 The Journal of Asian Finance, Economics and Busine Vol.10 No.2

        This research aims to identify the role that small and medium enterprises (SMEs) can play in achieving the economic goals of the vision of Saudi Arabia 2030. The study relied on descriptive analysis, designing a standard model, and analyzing it using the Eviews9 program. The study also adopted the questionnaire as a tool for data collection. The study area covered Alkharj and Hawtat Bani Tamim governorates. The sample size of the study was 142 participants. The study’s results confirmed the existence of a significant impact of changes in independent variables (X1, X2, X3, X4), which are (GDP, non-oil exports, number of employees, and public revenues), respectively. The dependent variable (Y) represents the number of small and medium-sized businesses in the Kingdom of Saudi Arabia. Additionally, it was found that 61.3% of small and medium-sized enterprises in the governorates of Al-Kharj and Hawtat Bani Tamim operate in the commercial sector. Most study participants concur that SMEs significantly lowered the unemployment rate and helped boost the GDP rate in the Kingdom of Saudi Arabia. The obstacles and difficulties facing the establishment of these enterprises were financial problems, marketing problems, and corporate monopoly. Furthermore, most of the small and medium l enterprises faced financing problems.

      • KCI등재

        Recent Progress on the Development of Antibiotics from the Genus Micromonospora

        Ali Zineddine Boumehira,Hesham Ali El-Enshasy,Hocine Hacene,Elsayed Ahmed Elsayed,Ramlan Aziz,Enoch Y. Park 한국생물공학회 2016 Biotechnology and Bioprocess Engineering Vol.21 No.2

        The emergence of a large number of antimicrobialresistant organisms is a cause for concern. Nature is historically the source of drugs; indeed a considerable number of drugs have been developed from microorganisms, and are now used daily in the treatment of infectious diseases. However, the introduction to the pharmaceutical market of new therapeutic molecules has decreased during the last two decades. In this review, the genus Micromonospora is proposed as a biofactory for production of new antibiotics. The genus Micromonospora has been investigated extensively and more than 100 antibiotics have been isolated from diverse Micromonospora strains. In addition, recent developments in analytical, biological and bioinformatics screening tools used in the discovery of new therapeutic compounds are described. It may be possible to revive formerly used antibiotics produced by Micromonospora and study of this genus may facilitate discovery of novel bioactive molecules.

      • KCI등재

        ISI and PAPR Immune IEEE 802.11p Channels Based on Single-Carrier Frequency Domain Equalizer

        ( Ahmed Ali ),( Wang Dong ),( Li Renfa ),( Esraa Eldesouky ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.11

        Doppler Effect is a prominent obstacle in vehicular networks, which dramatically increase the Bit-Error-Rate (BER). This problem is accompanied with the presence of the Orthogonal Frequency Division Multiplexing (OFDM) systems in which the Doppler shift interrupts the subcarriers orthogonality. Additionally, Inter-Symbol Interference (ISI) and high Peak-to-Average Power Ratio (PAPR) are likely to occur which corrupt the received signal. In this paper, the single-carrier combined with the frequency domain equalizer (SC-FDE) is utilized as an alternative to the OFDM over the IEEE 802.11p uplink vehicular channels. The Minimum Mean Squared Error (MMSE) and Zero-Forcing (ZF) are employed in order to study the impact of these equalization techniques along with the SC-FDE on the propagation medium. In addition, we aim to enhance the BER, improve the transmitted signal quality and achieve ISI and PAPR mitigation. The proposed schemes are investigated and we found that the MMSE outperforms the ZF equalization under different Doppler shift effects and modulations.

      • Channel Clustering and QoS Level Identification Scheme for Multi-Channel Cognitive Radio Networks

        Ali, Amjad,Yaqoob, Ibrar,Ahmed, Ejaz,Imran, Muhammad,Kwak, Kyung Sup,Ahmad, Adnan,Hussain, Syed Asad,Ali, Zulfiqar IEEE 2018 IEEE communications magazine Vol.56 No.4

        <P>The increasing popularity of wireless services and devices necessitates high bandwidth requirements; however, spectrum resources are not only limited but also heavily underutilized. Multiple license channels that support the same levels of QoS are desirable to resolve the problems posed by the scarcity and inefficient use of spectrum resources in multi-channel cognitive radio networks (MCRNs). One reason is that multimedia services and applications have distinct, stringent QoS requirements. However, due to a lack of coordination between primary and secondary users, identifying the QoS levels supported over available licensed channels has proven to be problematic and has yet to be attempted. This article presents a novel Bayesian non-parametric channel clustering scheme, which identifies the QoS levels supported over available license channels. The proposed scheme employs the infinite Gaussian mixture model and collapsed Gibbs sampler to identify the QoS levels from the feature space of the bit rate, packet delivery ratio, and packet delay variation of licensed channels. Moreover, the real measurements of wireless data traces and comparisons with baseline clustering schemes are used to evaluate the performance of the proposed scheme.</P>

      • Endophytic bacterial diversity of <i>Avicennia marina</i> helps to confer resistance against salinity stress in <i>Solanum lycopersicum</i>

        Ali, Amjad,Shahzad, Raheem,Khan, Abdul Latif,Halo, Boshera A.,Al-Yahyai, Rashid,Al-Harrasi, Ahmed,Al-Rawahi, Ahmed,Lee, In-Jung Informa UK (TaylorFrancis) 2017 Journal of plant interactions Vol.12 No.1

        <P>The current study aimed to explore the endophytic bacterial diversity of Avicennia marina and the potential roles of these endophytes in counteracting saline conditions in tomato plants. Molecular analysis revealed strains from Paenibacillus, Bacillus, Microbacterium, Citrobacter, Lysinibacillus, Halomonas, Virgibacillus, Exiguobacterium, and Vibrio. However, Bacillus pumilus AM11 and Exiguobacterium sp. AM25 showed significantly higher growth in saline media. In response to salinity stress, tomato plants treated with AM11 and AM25 showed significantly higher (similar to 15-23%) biomass, photosynthetic rate and pigment accumulation compared to controls. Salinity-exposed plants had significantly reduced growth and increased (three-fold) lipid peroxidation, whilst glutathione, catalase, and peroxidase activities were significantly reduced. In contrast, AM11, AM25, and methionine improved these physiochemical attributes. The study concludes that the application of bacterial endophytes from plants growing in saline conditions can offer other plants similar stress-resistance potential. Such halophytic bacterial strains can be used to improve plant growth in saline conditions.</P>

      • KCI등재

        Silver and zinc oxide nanoparticles induce developmental and physiological changes in the larval and pupal stages of Spodoptera littoralis (Lepidoptera: Noctuidae)

        Ahmed M.A. Ibrahim,Ali M. Ali 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.4

        The rapid growth of nanotechnology application in various fields of science led to need of understanding their possible effects on development and physiology of insects before using them as control agents. Instead of feeding on a toxic dose, the impact of silver nanoparticles (AgNPs, 50–60 nm) and zinc oxide nanoparticles (ZnONPs, 10–30 nm) was studied at a nonlethal concentration on the larval stages of Spodoptera littoralis. Late second instar larvae of S. littoralis were treated with water, 10 mg/mL AgNPs and ZnONPs dipped castor leaves for 6 days. Both nanoparticles treated leaves caused reduction in both larval weight gain and pupal weight than water dipped leaves while ZnONPs only caused extended larval period. ZnONPs increased total hemocyte, granular cell and plasmatocyte counts while AgNPs increased plasmatocytes only. ZnONPs decreased the levels of protein, lipids and carbohydrates than control and AgNPs treated larvae. On the contrary, ZnONPs induced significant increase in the activities of amylase, glucose 6 phosphate dehydrogenase (G6PD), lipase as well as two antioxidative enzymes, the catalase and superoxide dismutase. These results clearly show that ZnONPs ingestion interfere with the digestive and immunological physiology as well as the development of S. littoralis.

      • A Framework for Implementing Information Systems Integration to Optimize Organizational Performance

        Ali Sirageldeen Ahmed International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.10

        The primary aim of this study is to investigate the influence of Service Provider Quality (SPQ), System Quality (SQ), Information Quality (IQ), and Training Quality (TQ) on the interconnected aspect of organizational performance known as growth and development (GD). The study examined the influence of information systems (IS) on organisational performance and provided a theory-based technique for conducting research. The theoretical foundation for this study is derived from the widely employed [1]. IS success model in information systems research. The study's framework incorporates several novel elements, drawn from a comprehensive review of both recent and earlier literature, which researchers have utilized to evaluate the dimensions of [1]. In this study, we collected data from a diverse group of 348 individuals representing various industries through a web-based questionnaire. The collected data were subjected to analysis using SPSS. We conducted a multiple regression analysis involving 15 factors to assess several hypotheses regarding the relationship between the independent construct IS effectiveness and the dependent construct organizational performance. Several noteworthy descriptive statistics emerged, which hold significance for management. The study's findings strongly indicate that information systems exert a significant and beneficial influence on organizational performance. To sustain and continually enhance organizational effectiveness, the study recommends that managers periodically scrutinize and assess their information systems.

      • KCI등재
      • SCISCIESCOPUS

        PEGylated nanographene-mediated metallic nanoparticle clusters for surface enhanced Raman scattering-based biosensing

        Ali, Ahmed,Hwang, Eun Young,Choo, Jaebum,Lim, Dong Woo The Royal Society of Chemistry 2018 The Analyst Vol.143 No.11

        <P>Surface-enhanced Raman scattering (SERS) is an optical spectroscopy technique that can detect a variety of analytes with high sensitivity and selectivity without any labels. Controlled clustering of metallic nanoparticles to prepare a new class of SERS nanotags is crucial for the ultra-sensitive detection of specific biological and chemical moieties because increased plasmonic hotspot junctions produce a greatly enhanced SERS signal. We report herein that controlled clustering of Au nanoparticles (AuNPs) was mediated by PEGylated nano-sized graphene (PNG) and that the PNG-induced AuNP clusters (PNG-AuNPCs) were highly sensitive SERS nanotags with colloidal stability for SERS-based biosensing. The AuNPs labeled with 4-mercaptopyridine as a Raman reporter were surface-modified with 1-aminomethylpyrene for the introduction of hydrophobic moieties, and were non-covalently complexed with PNG <I>via</I> π-π stacking and van der Waals forces. It resulted in the formation of PNG-AuNPCs that increased SERS intensity with an enhancement factor of 1.34 × 10<SUP>11</SUP>. The PNG induced a high degree of AuNP clustering by enhancing the non-covalent interactions between them, resulting in increased hotspot junctions at highly localized plasmonic centers. Furthermore, to show that the PNG-AuNPCs would serve as stable, reproducible, and highly sensitive SERS nanotags for biosensing, we formed sandwich-type immunocomplexes composed of the PNG-AuNPCs, immunoglobulin G (IgG) as the antigen, and magnetic beads. We found a linear relationship between SERS intensity and IgG concentration, with a limit of detection lower than 31.0 fM for IgG detection. Thus, the PNG-AuNPCs could be useful as SERS nanotags for highly sensitive SERS-based biosensing applications.</P>

      • KCI등재

        Effect of Pressure on Liquid Absorbance in Main Wood Species of Pinaceae Grown in Korea Using Safranine Under Vacuum

        Ahmed Sheikh Ali,Park Hyun-Dae,Chun Su-Kyoung Korea Furniture Society 2005 한국가구학회지 Vol.16 No.2

        본 실험은 한국산 주요 침엽수인 소나무, 잣나무, 리기다소나무, 낙엽송의 safranine의 침투도를 실험하였다. 진공, 압력 및 safranine의 침투시간을 각각 다르게 하여 수종별 침투도를 측정하였다. 실험 결과 진공조건의 변화에 따른 침투도 변이는 크게 나타나지 않았고, 압력조건의 차이에 의한 침투도는 다르게 나타났다. 목재의 방향별 침투도를 고찰한 길과 축방향, 방사방향, 접선 방향의 순서로 침투도가 높았다. 변재와 심재의 사이의 침투성을 고찰 한 결과 변재가 심재보다 쉽게 침투 되었다. 수종별 침투성을 고찰한 결과 소나무가 가장 우수했다.

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