• 제목/요약/키워드: Muhammad Iqbal

검색결과 84건 처리시간 0.021초

Effect of chiral structure for free vibration of DWCNTs: Modal analysis

  • Asghar, Sehar;Naeem, Muhammad N.;Khadimallah, Mohamed Amine;Hussain, Muzamal;Iqbal, Zafar;Tounsi, Abdelouahed
    • Advances in concrete construction
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    • 제9권6호
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    • pp.577-588
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    • 2020
  • In this paper, vibration attributes of chiral double-walled carbon nanotubes (CNTs) based on nonlocal elastic shell model have been investigated. The impact of small scale is being perceived by establishing Flügge shell model. The wave propagation is engaged to frame the ruling equations as eigen value system. The influence of nonlocal parameter subjected to different end supports has been overtly examined. A suitable choice of material properties and nonlocal parameter been focused to analyze the vibration characteristics. The new set of inner and outer tubes radii investigated in detail against aspect ratio and length. The dominance of boundary conditions via nonlocal parameter is shown graphically. Whereas for lower aspect ratio the frequencies coincide but as it continues to expand the difference between all respective boundary conditions slightly tend to increase. The results generated furnish the evidence regarding applicability of nonlocal shell model and also verified by earlier published literature.

포항 지진의 진원 깊이 연구 (A Study of Hypocentral Depth of Pohang Earthquake)

  • 정태웅;이영민;모하메드 자파르;정진아
    • 지구물리와물리탐사
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    • 제21권2호
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    • pp.125-131
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    • 2018
  • 2017년 11월 15일 포항지진(규모 5.4)은 깊이효과로 경주지진(규모 5.8) 보다 피해가 더 컸으나, 정확한 깊이가 확증되지 않고 있다. 진원 깊이를 진원재결정을 통하여 역산한 결과, 대부분의 모델의 진원 깊이가 얕은 표층으로 도출된 반면, 지각구조가 가장 근접한 모델은 6.0 ~ 11.5 km 구간의 깊이로 산출되었다. 지온분석에서는 7.5 km 근방에서 $300^{\circ}C$의 온도가 관찰되어 지진유발층의 사례에 입각한 포항지진의 진원은 근접한 모델로 얻어진 7 km 근방인 것으로 추정되어진다.

Erratum to: Severe combined immunodeficiency pig as an emerging animal model for human diseases and regenerative medicines

  • Iqbal, Muhammad Arsalan;Hong, Kwonho;Kim, Jin Hoi;Choi, Youngsok
    • BMB Reports
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    • 제52권12호
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    • pp.718-727
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    • 2019
  • Severe combined immunodeficiency (SCID) is a group of inherited disorders characterized by compromised T lymphocyte differentiation related to abnormal development of other lymphocytes [i.e., B and/or natural killer (NK) cells], leading to death early in life unless treated immediately with hematopoietic stem cell transplant. Functional NK cells may impact engraftment success of life-saving procedures such as bone marrow transplantation in human SCID patients. Therefore, in animal models, a T cell-/B cell-/NK cell+ environment provides a valuable tool for understanding the function of the innate immune system and for developing targeted NK therapies against human immune diseases. In this review, we focus on underlying mechanisms of human SCID, recent progress in the development of SCID animal models, and utilization of SCID pig model in biomedical sciences. Numerous physiologies in pig are comparable to those in human such as immune system, X-linked heritability, typical T-B+NK- cellular phenotype, and anatomy. Due to analogous features of pig to those of human, studies have found that immunodeficient pig is the most appropriate model for human SCID.

Severe combined immunodeficiency pig as an emerging animal model for human diseases and regenerative medicines

  • Iqbal, Muhammad Arsalan;Hong, Kwonho;Kim, Jin Hoi;Choi, Youngsok
    • BMB Reports
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    • 제52권11호
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    • pp.625-634
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    • 2019
  • Severe combined immunodeficiency (SCID) is a group of inherited disorders characterized by compromised T lymphocyte differentiation related to abnormal development of other lymphocytes [i.e., B and/or natural killer (NK) cells], leading to death early in life unless treated immediately with hematopoietic stem cell transplant. Functional NK cells may impact engraftment success of life-saving procedures such as bone marrow transplantation in human SCID patients. Therefore, in animal models, a T cell-/B cell-/NK cell+ environment provides a valuable tool for understanding the function of the innate immune system and for developing targeted NK therapies against human immune diseases. In this review, we focus on underlying mechanisms of human SCID, recent progress in the development of SCID animal models, and utilization of SCID pig model in biomedical sciences. Numerous physiologies in pig are comparable to those in human such as immune system, X-linked heritability, typical T-B+NK- cellular phenotype, and anatomy. Due to analogous features of pig to those of human, studies have found that immunodeficient pig is the most appropriate model for human SCID.

Effect of Ammonium Persulfate Concentration on Characteristics of Cellulose Nanocrystals from Oil Palm Frond

  • ZAINI, Lukmanul Hakim;FEBRIANTO, Fauzi;WISTARA, I Nyoman Jaya;N, Marwanto;MAULANA, Muhammad Iqbal;LEE, Seung Hwan;KIM, Nam Hun
    • Journal of the Korean Wood Science and Technology
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    • 제47권5호
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    • pp.597-606
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    • 2019
  • Cellulose nanocrystals (CNCs) were successfully isolated from oil palm fronds (OPFs) using different concentrations of ammonium persulfate (APS), and their characteristics were analyzed by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, and thermogravimetric analysis (TGA). APS oxidation effectively isolated CNCs with rod-like morphology in nanometer scale. The dimensions of the CNCs decreased with increasing APS concentration. FTIR and XRD analyses revealed that all the CNCs showed crystals in the form of cellulose I without crystal transformation occurring during APS treatment. The relative crystallinity of the CNCs increased with increasing APS concentration, whereas their thermal stability decreased. An APS concentration of 2 M was found to be optimal for isolating the CNCs.

Effect of suction on flow of dusty fluid along exponentially stretching cylinder

  • Iqbal, Waheed;Jalil, Mudassar;Qazaq, Amjad;Khadimallah, Mohamed A.;Naeem, Muhammad N.;Hussain, Muzamal;Mahmoud, S.R.;Ghandourah, E.;Tounsi, Abdelouahed
    • Advances in nano research
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    • 제10권3호
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    • pp.263-270
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    • 2021
  • The present manuscript focuses the effects of suction on the flow of the dusty fluid along permeable exponentially stretching cylinder. Derived PDEs for this work are changed into ODEs by adopting right transformations. Numerical procedure is carried out for the obtained resultant equations by Shooting Technique in accordance with Runge-Kutta (RK-6) technique. Obtained results for the parameters namely, particle interaction parameter, suction parameter and Reynold number parameters are probed thoroughly. Some salient points are: (a) Fluid velocity decreases and the dust phase velocity rises for the higher values of particle interaction parameter; (b) more suction produces retarding velocities for both the phases; (c) high Reynold number slows down the fluid velocity while the speed of dust phase and (d) skin friction coefficient goes high for all these parameters.

Links Between Macro Facilitators of Organizational Empowerment and Ambidextrous Behaviors: An Empirical Study from Pakistan

  • IQBAL, Sumaira;PARVEZ, Anjum;ANJUM, Muhammad Adeel;SAFDAR, Tayybah;AHMED, Ammarah
    • The Journal of Asian Finance, Economics and Business
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    • 제9권2호
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    • pp.113-120
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    • 2022
  • The goal of this study is to see if there's a relationship between employees' ambidextrous behaviors and macro facilitators of organizational empowerment (such as control over workplace decisions, dynamic structural framework, and fluidity in information sharing) (exploration and exploitation). To acquire data, this study uses survey methods. A cross-sectional survey was done to collect information from academics at five large public sector universities in Pakistan's Balochistan province. Control over workplace decisions boosts academics' engagement in exploration and exploitation, while a dynamic structural framework merely increases their engagement in exploration, according to the findings based on data from 240 respondents (n = 240). The findings also show that information sharing flexibility has little effect on exploration and exploitation behaviors. In conclusion, the results of this study imply that organizational empowerment is critical for academics' ambidextrous behaviors to thrive. As a result, specific organizational facilitators of empowerment (such as control over workplace decisions and a dynamic structural framework) are advised in higher education institutions. This research is significant because it develops and tests a model that explains hitherto unexplored connections between macro facilitators of organizational empowerment and employees' ambidextrous behaviors. In addition, the research provides important insights for managerial practice and research.

Performance of Food Products Distribution During the COVID-19 Pandemic in Indonesia

  • TRIYONO, TRIYONO;AKHMADI, Heri;YULIANTO, Iqbal Muhammad;RIPTANTI, Erlyna Wida
    • 유통과학연구
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    • 제20권10호
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    • pp.67-77
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    • 2022
  • Purpose: This study aims to determine the online shop service performance of fresh food products distribution, consumer motivation, and their relationship during the COVID-19 pandemic. Research design, data, and methodology: A survey was conducted online using Google Forms on 100 consumers of TaniHub application users. Data in the form of scale were analyzed descriptively to explain the service performance and consumer motivation. The service performance consists of technical services and marketing services. Technical service indicators consist of payment, delivery, and products. Meanwhile, the marketing service indicator consists of promotions and prices. The consumer motivation is characterized by reference, actualization, and lifestyle. The relationship between the two was analyzed using Spearman's rank correlation. Results: The most consumers are millennial generation who were active in social media. They are employees with Bachelor's and Master's qualifications and included in the middle economic groups. TaniHub online shop had good technical and fair marketing performance. The motivation of online shop consumers of fresh food products through the TaniHub application was high. Conclusions: The findings discovered a significant relationship between online shop service performance and consumer motivation. It indicates the need for improvement in marketing services, especially promotions, to improve the performance of this e-agribusiness company.

The Relationship Between Capital Structure and Firm Performance: New Evidence from Pakistan

  • ISLAM, Zia ul;IQBAL, Muhammad Mazhar
    • The Journal of Asian Finance, Economics and Business
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    • 제9권2호
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    • pp.81-92
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    • 2022
  • The necessity for a theoretical explanation of the negative association between capital structure and company performance is identified in this study. By focusing on accounting metrics of business performance, this study is the first to investigate the moderating effects of firm size between these variables using logical reasoning. Due to the possibility of endogeneity, this study applies a two-step system GMM approach with data from 285 non-financial enterprises from PSX over a 21-year period. For robustness, we employed pooled OLS, fixed effect, and two-step difference GMM. Our data show that leverage has a detrimental impact on business performance, with size acting as a moderator in the same direction. Our analysis empirically supports some studies while refuting others due to inconsistent results in the literature, but no study has theoretically justified their negative link. We believe that because larger companies have more and easier access to capital markets, they focus primarily on the amount of return, even if the investment is inefficient in terms of the rate of return, but small businesses do not. As a result of this thinking, firm managers' performance suffers as a result of leverage.

The Impact of Demographic Characteristics of Board of Directors and Audit Committee on Financial Reporting Quality: An Empirical Study from Pakistan

  • SHAHEEN, Sanober;IQBAL, Muhammad Mazhar
    • The Journal of Asian Finance, Economics and Business
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    • 제9권1호
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    • pp.345-352
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    • 2022
  • This study examines the impact of female representation on board of directors and audit committees on financial reporting quality, which also discusses the moderating role of family ownership in female representation on boards of directors and audit committees and financial reporting quality. The unbalanced panel is made up of 271 non-financial companies listed on the Pakistan Stock Exchange (PSX) from 2008 to 2019.The findings reveal that female representation on the board of directors has a large and negative impact on financial reporting, but female representation on the audit committee has a significant positive impact on financial reporting quality. Furthermore, the results reveal that family ownership has a negative impact on the relationship between female presence on boards of directors and financial reporting quality. Furthermore, the findings show that family ownership reduces the impact of female involvement in audit committees on the quality of financial reporting. However, family ownership has no direct impact on financial reporting quality.Our findings suggest that selecting females to serve on boards of directors and audit committees should be based on specific criteria (e.g., monitoring abilities, business competence, knowledge, and experience) rather than on family relationships.