Influence Of Microplastic Aging On Its Interaction With Aquatic Humic Substances

Rabia Zafar(ZAFAR RABIA),Jin Hur(허진) 대한환경공학회 2021 대한환경공학회 학술발표논문집 Vol.2021 No.11

Security Threats and Attacks in IoT-Based Home Automation

Rabia Afzaal,Safa Hussain,Rania Naveed,Sadaf Hussain,Muhammad Adnan Khan 한국차세대컴퓨팅학회 2023 한국차세대컴퓨팅학회 학술대회 Vol.2023 No.12

Over the past few decades, home automation systems have gained significant popularity due to their ability to enhance comfort and improve the quality of life. However, with the increasing reliance on internet connectivity, these systems face challenges in coping with the expanding attack surfaces and the corresponding attacks. This paper provides an overview of the attacks that commonly target smart home devices and networks. It explores the vulnerabilities that can be exploited by attackers to compromise the security and privacy of these systems. Furthermore, the paper proposes and discusses potential solutions and countermeasures to mitigate these attacks. By understanding the nature of these threats and implementing appropriate security measures, homeowners and system developers can enhance the security posture of smart home systems, ensuring a safer and more secure environment.

Predictions of the maximum plate end stresses of imperfect FRP strengthened RC beams: study and analysis

Rabia, Benferhat,Daouadji, Tahar Hassaine,Abderezak, Rabahi Techno-Press 2020 Advances in materials research Vol.9 No.4

A theoretical method to predict the interfacial stresses in the adhesive layer of reinforced concrete beams strengthened with porous FRP plate is presented in this paper. The effect due to porosity is incorporated utilizing a new modified rule of mixture covering the porosity phases. The adherend shear deformations have been included in the present theoretical analyses by assuming a linear shear stress through the thickness of the adherends. Remarkable effect of the porosity has been noted in the results. Indeed, the resulting interfacial stresses concentrations are considerably smaller than those obtained by other models which neglect the porosity effect. It was found that the interfacial stresses are highly concentrated at the end of the FRP plate, the minimization of the latter can be achieved by using porous FRP plate in particular at the end. It is also shown that the interfacial stresses of the RC beam increase with volume fraction of fibers, but decrease with the thickness of the adhesive layer.

Women leaders in Pakistani academia : Challenges and opportunities

Rabia Ali,Asma Rasheed 이화여자대학교 한국여성연구원 2021 Asian Journal of Women's Studies(AJWS) Vol.27 No.2

Research on women’s leadership has been largely male-centric and has used masculine characteristics to measure and evaluate such roles. This paper aims to unveil women’s leadership in Pakistani universities. Using a feminist perspective, we argue that female academics encounter multiple barriers at work. The data for this paper was collected via in-depth interviews with twelve women leaders from public universities in Islamabad, Pakistan to understand their experiences. Our findings show how our research participants struggled in order to navigate their careers. This paper documents organizational factors such as male-dominated networks, stereotypes and personal factors, for instance, time spent on familial roles that may hamper their positions. Clearly, they encountered constraints in reaching top management levels and sustaining these. However, in order to achieve such positions these women acknowledged the support of family, their high socioeconomic status and effective networking and mentoring relations with peers. The insights gained by this study illustrate how they navigated the male-centric realm of higher education and these should be useful for those who aspire to be leaders. Our research should also offer some potential strategies for closing the gender gap in universities by facilitating women to assume leadership positions. خواتین کی قیادت کے بارے میں زیادہ تر تحقیقات مردوں نے انجام دی ہیں اور انھوں نے اس طرح کے کرداروں کی جانچ اور تشخیص کے لئے مذکر خصوصیات کو استعمال کیا ہے۔ اس مقالے کا مقصد پاکستانی یونیورسٹیوں میں خواتین کی قیادت کی نقاب کشائی کرنا ہے۔ حقوق نسواں کے نقطہ نظر کا استعمال کرتے ہوئے ، ہم بحث کرتے ہیں کہ خواتین ماہرین تعلیم کو کام کے دوران متعدد رکاوٹوں کا سامنا کرنا پڑتا ہے۔ اس مقالے کے اعداد و شمار کو اسلام آباد ، پاکستان کی سرکاری یونیورسٹیوں سے بارہ خواتین رہنماؤں کے ساتھ تفصیلی انٹرویو کے ذریعے اکٹھا کیا گیا ہے۔ ہماری تحقیقات سے پتہ چلتا ہے کہ ہمارے تحقیقی شرکا نے تعلیمی پیشوا کی حیثیت سے اپنے کیریئر کو چلانے کے لئے کس طرح جدوجہد کی۔ اس مقالے میں تنظیمی عوامل جیسے مرد سے چلنے والے نیٹ ورکس ، دقیانوسی تصورات اور ذاتی عوامل جیسے دستاویزی کرداروں پر صرف ہونے والے وقت کو دستاویز کیا گیا ہے۔ جن کی وجہ سے خواتین کوقائدانہ صلاحیت ادا کرنے میں رکاوٹ پیش آتی ہے ۔ ظاہری طور پر انھیں انتظامیہ کی اعلی سطح تک پہنچنے اور ان کو برقرار رکھنے میں رکاوٹوں کا سامنا کرنا پڑتا ہے۔ تاہم قائدانہ عہدوں کے حصول کے لیے ان خواتین نے کنبہ کی حمایت ، معاشرے میں ان کی مضبوط معاشرتی و اقتصادی حیثیت ، اور ہم عمر افراد کے ساتھ موثر نیٹ ورکنگ اور رہنمائی کرنے والے تعلقات کو قبول کیا۔ اس مطالعے میں حاصل کردہ نتائج سے یہ واضح ہوتا ہے کہ انہوں نے کس طرح اعلی تعلیم کے مرد مرکوز دائرے کو عبورکیا - ہمارے مطالعہ کے نتائج ان لوگوں کےلیے کارآمد ثابت ہونے چاہئیں جو قائدانہ کردار ادا کرنے کی خواہش رکھتے ہیں۔ ہمارے مطالعے سے یونیورسٹیوں میں صنفی فرق کو ختم کرنے اورخواتین کو قائدانہ منصب سنبھالنے میں سہولیات فراہم کرنے کے لئے رہنمائی مل سکتی ہے۔

Adsorptive Behavior of Catechol Violet and Its Thorium Complex on Mercury Electrode in Aqueous Media

Rabia Mostafa K. M. The Korean Electrochemical Society 2004 한국전기화학회지 Vol.7 No.1

Cyclic voltammetry and chronocoulometry have been used for characterization of catechol violet (CV) at the hanging mercury drop electrode in acetic acid-sodium acetate buffer solution. At pH 2.94 a nearly symmetric cyclic voltammetric wave due to an irreversible weak adsorption of CV on mercury was obtained at concentration of $0.53{\mu}mol\;dm ^{-3}$. Under these conditions, CV adsorbes in a monolayer. Upon increasing the concentration, the symmetry of the wave decreases; it can be attributed to a mixed diffusion adsorption process. The amount of the adsorbed catechol violet on the HMDE expressed as surface concentration as well as the surface areaf occupied by one molecule$(\sigma)$ were calculated. It was found that the values obtained for f and o utilizing cyclic voltammetric and chrono-coulometry are almost identical. A 1:1 and 1:2 Th (IV)-CV complexes are formed on addition of thorium (IV) to catechol violet. These complexes are adsorbed and reduced on the HMDE at more negative potentials than the peak potential of free CV, Using the square-wave (SW) technique, the adsorptive cathodic stripping voltammetry, ACSV, of these complexes was studied. It was found that the SW-ACSV of Th(IV)-CV can be applied to the determination of thorium at the nanomole level. Optimum conditions and the analytical method of determination were presented and discussed.

Structural, dielectric and magnetic properties of cobalt based spinel ferrites

Rabia Qindeel,Norah H. Alonizan 한국물리학회 2018 Current Applied Physics Vol.18 No.5

CoYbxFe2-xO4 (x=0.00, 0.025, 0.05, 0.075, 0.10) spinel ferrites were synthesized by co-precipitation technique. Structural, dielectric and magnetic properties were measured. X-ray diffraction analysis showed that all the prepared spinel ferrites possessed cubic spinel structure. Dielectric constant, AC conductivity and dielectric loss decreased with the addition of rare earth ions. The impedance analysis explained the role of grains and grain boundaries with in prepared samples. Cole-Cole plots helped to measure the values of grains and grain boundary's resistance. The magnetic properties proved the soft nature of these ferrites. Saturation magnetization and remanence decreased while coercivity was enhanced with the addition of ytterbium concentration. All these parameters suggested that these prepared samples might be suitable for high frequency applications.

Accurate Camera Self-Calibration based on Image Quality Assessment

Rabia Fayyaz,이은주 한국데이터전략학회 2018 Journal of information technology applications & m Vol.25 No.2

This paper presents a method for accurate camera self-calibration based on SIFT Feature Detection and image quality assessment. We performed image quality assessment to select high quality images for the camera self-calibration process. We defined high quality images as those that contain little or no blur, and have maximum contrast among images captured within a short period. The image quality assessment includes blur detection and contrast assessment. Blur detection is based on the statistical analysis of energy and standard deviation of high frequency components of the images using Discrete Cosine Transform. Contrast assessment is based on contrast measurement and selection of the high contrast images among some images captured in a short period. Experimental results show little or no distortion in the perspective view of the images. Thus, the suggested method achieves camera self-calibration accuracy of approximately 93%.

Analysis and sizing of RC beams reinforced by external bonding of imperfect functionally graded plate

Rabia, Benferhat,Daouadji, Tahar Hassaine,Abderezak, Rabahi Techno-Press 2021 Advances in materials research Vol.10 No.2

An analytical method based on the compatibility of deformations and equilibrium of forces is investigated to predict the reinforcement plate area in concrete beams strengthened with Functionally Graded (FG) plates bonded to the tension face of the beams. The models are given for beams having rectangular and T-cross-sections. The effect of porosity that can happen inside FGM materials during their manufacture is also shown. New rules of the mixture that take into account different distribution rates of porosity in FG plates have been developed in this study. A parametric study is conducted to investigate the effect of several parameters such as the ultimate moment, plate stiffness, the distribution rate of the porosity, and compressive strength of the concrete. The results obtained show a significant gain in the reinforcement plate area of the RC beam strengthened with an FG plate relative to another reinforced with FRP plate, which makes it possible to reduce the interfacial stresses and prevents detachment of the reinforcing plate.

Analytical analysis of the interfacial shear stress in RC beams strengthened with prestressed exponentially-varying properties plate

Rabia, Benferhat,Abderezak, Rabahi,Daouadji, Tahar Hassaine,Abbes, Boussad,Belkacem, Adim,Abbes, Fazilay Techno-Press 2018 Advances in materials research Vol.7 No.1

In this paper, a closed-form rigorous solution for interfacial shear stress in simply supported beams strengthened with bonded prestressed E-FGM plates and subjected to an arbitrarily positioned single point load, or two symmetric point loads is developed using linear elastic theory. This improved solution is intended for application to beams made of all kinds of materials bonded with a thin plate, while all existing solutions have been developed focusing on the strengthening of reinforced concrete beams, which allowed the omission of certain terms. The theoretical predictions are compared with other existing solutions. Finally, numerical results from the present analysis are presented to study the effects of various parameters of the beams on the distributions of the interfacial shear stresses. The results of this study indicated that the E-FGM plate strengthening systems are effective in enhancing flexural behavior of the strengthened RC beams.

Comparison of surficial modification of micro-sized polyethylene in between by UV/O₃ and UVO submerged system

Rabia Zafar,Seon Yeong Park,Chang Gyun Kim 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.3

This study examined the effects of ozonation and UV applied in series (O₃+UV) or simultaneously (UVO) under four different ozone dosages from 4 to 7 mg/min to understand the surface alterations on polyethylene microplastics in aquatic environments via the photochemical oxidation process. The plastic samples were analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle measurements. FTIR spectroscopy showed that the levels of carbonyl (ketone and esters) and vinyl groups increased gradually with increasing ozone dose injected; the highest was observed at 6 mg/min of ozone. On the other hand, the levels at 7 mg/min of ozone were slightly lower than those at 4 to 6 mg/min. This could be related to the deeper penetration into the crystalline bulk polymeric chain. The contact angle changed from 125.90˚ to the lowest value of 120.04˚ and 123.8˚ for O₃+UV and UVO, respectively. Furthermore, XPS showed that C-O was only presented in the 7 mg/min sample, whereas C-O, OH, C=O, and C-C=O remained for 4 to 6 mg/min. Overall, O₃+UV can oxidize the surface of the polyethylene microplastic particles more effectively than those of UVO, irrespective of the ozone dosages.