Effect of Y2O3 doping on the electrical transport properties of Sr2MnNiFe12O22 Y-type hexaferrite

Muhammad Irfan,M.U. Islam,Irshad Ali,M. Asif Iqbal,Nazia Karamat,Hasan M. Khan 한국물리학회 2014 Current Applied Physics Vol.14 No.1

Y2O3 doped Y-type composite hexa-ferrites Sr2MnNiFe12O22 þ xY2O3 (x ¼ 0 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%) were synthesized successfully using sol-gel auto combustion technique. X-ray diffraction analysis reveals Y-type hexagonal structure with few traces of secondary phases. The decrease in grain size as a function of Yttrium content is attributed to the fact that Yttrium acts as a grain inhibitor. The DC resistivity was observed to increase with increasing Yttrium-contents due to the unavailability of Fe3þ ions at octahedral sites. Activation energy showed that the samples with high resistivity have high value of activation energy and vice versa. Permittivity decreases with the increase of frequency following MaxwellWagner Model. In addition, the doped samples exhibit very low dielectric constant and low loss tangent in frequency range 20 Hze1 MHz. The sample x ¼ 5 wt% exhibit the lowest value of dielectric constant. The variation in imaginary part of dielectric constant and loss tangent with frequency show normal dielectric behavior for all the samples. The frequency dependent ac conductivity increases with increase in frequency and decrease with Y2O3 doping. These characteristics may be suitable for their potential applications in electromagnetic attenuation materials and microwave devices. The conductivity mechanism so determined was hopping mechanism. The dc resistivity of the doped ferrites measured in our case is about 1010 U-cm that meets the requirement for fabrication of components by electroplating.

ndnCSIM: A Microservices based Compute Simulator for NDN

Muhammad Atif U Rehman,Muhammad Salahuddin,Muhammad Imran,Sana Fayyaz,Byung Seo Kim 대한전자공학회 2021 대한전자공학회 학술대회 Vol.2021 No.6

Ulnar artery access for intracranial mechanical thrombectomy procedure: A salvage option after failed trans-femoral and trans-radial access

Muhammad U Manzoor,Abdullah A. Alrashed,Ibrahim A. Almulhim,Sultan Alqahtani,Fahmi Al Senani 대한뇌혈관외과학회 2023 Journal of Cerebrovascular and Endovascular Neuros Vol.25 No.4

84 years old gentle man with past medical history of hypertension and diabetes presented with sudden onset right sided weakness and aphasia for two hours. Initial neurological assessment revealed National Institute of Health Stroke Scale (NIHSS) 17. Computed tomography (CT) scan demonstrated minimal early ischemic changes along left insular cortex with occlusion of left middle cerebral artery (MCA). Based on clinical and imaging findings, decision was made to perform mechanical thrombectomy procedure. Initially, right common femoral artery approach was utilized. However, due to unfavorable type-III bovine arch, left internal carotid artery could not be engaged via this approach. Subsequently, access was switched to right radial artery. Angiogram revealed small caliber radial artery, with larger caliber ulnar artery. Attempt was made to advance the guide catheter through the radial artery, however significant vasospasm was encountered. Subsequently, ulnar artery was accessed and successful thrombolysis in cerebral infarction (TICI) III left MCA reperfusion was achieved with a single pass of mechanical thrombectomy via this approach. Post procedure neurological examination demonstrated significant clinical improvement. Doppler ultrasound 48 hours after the procedure demonstrated patent flow in radial and ulnar arteries with no evidence of dissection.

Initial experience with Scepter Mini dual lumen balloon for embolization of cerebrovascular diseases

Muhammad U Manzoor,Ibrahim A. Almulhim,Abdullah A. Alrashed,Shorog Althubait,Abdulrahman Y. Alturki,Sultan M. Al-Qahtani 대한뇌혈관외과학회 2023 Journal of Cerebrovascular and Endovascular Neuros Vol.25 No.2

Objective: Endovascular treatment of cerebrovascular diseases is often challenging due to small caliber, tortuous distal vessels. Several devices and techniques have evolved to overcome these challenges. Recently, a low profile dual lumen microballoon catheter, specifically designed for distal navigation is employed for neurovascular procedures. Due to its recent advent, scarce data is available on clinical utility and safety of Scepter Mini. The aim of this case series is to report our initial experience with Scepter Mini in the management of various cerebrovascular diseases.Methods: All interventional neurovascular cases performed using Scepter Mini between January 2020 till April 2021 were included. Data regarding patient demographics, procedural details and complications was retrospectively collected from patient’s electronic medical record and procedure reports.Results: Total twelve embolization procedures were performed in eleven patients, including six brain arteriovenous malformation, two dural arteriovenous fistula, one vein of Galen malformation and three hyper-vascular glomus tumor embolizations. All procedures were successfully performed with adequate penetration of the embolic agent. Complete embolization was performed in six procedures, while intended partial embolization was performed in the rest of procedures. Scepter Mini was solely used in ten procedures, however in the other two embolization procedures it was used as an additional conjunct tool to complete the intended embolization. No balloon related complication was observed in any procedure.Conclusions: Scepter Mini dual lumen microballoon catheter is safe and feasible for delivery of liquid embolic agents for cerebrovascular embolization procedures.

Station based Profile of Extreme Rainfall Events in the Punjab Province of Pakistan during 1981-2014

Muhammad Nasar u Minallah,알리 시라지,미안 사비르 후세인 건국대학교 기후연구소 2018 기후연구 Vol.13 No.2

The changes in extreme daily rainfall totals in Punjab Province, Pakistan, during the period (1981-2014) are examined in this study. The analysis was focused on the extreme annual and monthly rainfall events, by processing the exceeding of the daily rainfall over various thresholds, which are indicators for the incidence of extreme rainfall events. To analyze the changes in extreme rainfall events and trends of the time series of the annual number of extreme rainfall days (%) the thresholds of 30mm and 50mm has been estimated. Evidence from the twelve stations considered shows that there is an increase in annual number of extreme rainfall days (%) in dataset. These changes of heavy and extreme rainfall events pronounce significant environmental consequences which cause considerable impact on society.

The Effect of Corporate Governance Practices on Firm Performance: Evidence from Pakistan

Hussain Muhammad,Ashfaq U. Rehman,Muhammad Waqas 한국유통과학회 2016 Asian Journal of Business Environment (AJBE) Vol.6 No.1

Purpose – The purpose of this study is to investigate the effect of corporate governance practices such as (board size, board composition, CEO duality and audit committee) on the performance of selected Pakistani firms. Research design, data, and methodology – This study examines corporate governance structure by using the data of 80 non-financial firms listed on Karachi Stock Exchange Pakistan during 2010-2014. Hypotheses of the study were tested by using both descriptive and inferential statistics. Result – The findings indicate that board size and audit committee is positively related to the firm performance (ROA & ROE). In contrast, board composition and CEO duality are negatively related to the firm performance (ROA & ROE). As far as controlling variables is concerned, leverage is negative, whereas firm size is positively related to all measures of performance. Conclusions – Empirical findings concluded that corporate governance practices affect the firm performance. Therefore, it is suggested that managers should understand the governance mechanisms to work more efficiently in the firm

The Relationship between Working Capital Management and Profitability: A Case Study of Tobacco Industry of Pakistan

Hussain Muhammad,Ashfaq U Rehman,Muhammad Waqas 한국유통과학회 2016 KODISA ICBE (International Conference on Business Vol.2016 No.-

Firms can use working capital management which is one of the essential determinants to influence their profitability. The main theme of present study is to investigate the relationship between working capital management and profitability of Tobacco Industry of Pakistan. This study is based on secondary data collected from financial statements of selected companies of Tobacco Industry of Pakistan for the period of 2005-2014. For data analysis, both descriptive and inferential statistics were used. Correlation analysis is used to check the relationship between the variables, while multiple regression analysis is used to examine the effects of working capital management on profitability of firms. The result reveals that there is a strong negative relationship between variables of working capital management and profitability of Tobacco Industry of Pakistan. This means that as the cash conversion cycle increases, it will lead to declining of firm profitability and managers can create a positive value for shareholders by reducing the cash conversion cycle at optimal level. The study concludes that managers can create value for shareholders by managing the working capital well designed and implemented, and by keeping each components of it at optimal level.

Raspberry Pi assisted facial expression recognition framework for smart security in law-enforcement services

Sajjad, Muhammad,Nasir, Mansoor,Ullah, Fath U Min,Muhammad, Khan,Sangaiah, Arun Kumar,Baik, Sung Wook Elsevier science 2019 Information sciences Vol.479 No.-

<P><B>Abstract</B></P> <P>Facial expression recognition is an active research area for which the research community has presented a number of approaches due to its diverse applicability in different real-world situations such as real-time suspicious activity recognition for smart security, monitoring, marketing, and group sentiment analysis. However, developing a robust application with high accuracy is still a challenging task mainly due to the inherent problems related to human emotions, lack of sufficient data, and computational complexity. In this paper, we propose a novel, cost-effective, and energy-efficient framework designed for suspicious activity recognition based on facial expression analysis for smart security in law-enforcement services. The Raspberry Pi camera captures the video stream and detects faces using the Viola Jones algorithm. The face region is pre-processed using Gabor filter and median filter prior to feature extraction. Oriented FAST and Rotated BRIEF (ORB) features are then extracted and the support vector machine (SVM) classifier is trained, which predicts the known emotions (Angry, Disgust, Fear, Happy, Neutral, Sad, and Surprise). Based on the collective emotions of the faces, we predict the sentiment behind the scene. Using this approach, we predict if a certain situation is hostile and can prevent it prior to its occurrence. The system is tested on three publically available datasets: Cohen Kande (CK+), MMI, and JAFEE. A detailed comparative analysis based on SURF, SIFT, and ORB is also presented. Experimental results verify the efficiency and effectiveness of the proposed system in accurate recognition of suspicious activity compared to state-of-the-art methods and validate its superiority for enhancing security in law enforcement services.</P>

The Relationship between Working Capital Management and Profitability: A Case Study of Tobacco Industry of Pakistan

Hussain Muhammad,Ashfaq U. Rehman,Muhammad Waqas 한국유통과학회 2016 The Journal of Asian Finance, Economics and Busine Vol.3 No.2

Firms can use working capital management which is one of the essential determinants to influence their profitability. The main theme of present study is to investigate the relationship between working capital management and profitability of Tobacco Industry of Pakistan. This study is based on secondary data collected from financial statements of selected companies of Tobacco Industry of Pakistan for the period of 2005-2014. For data analysis, both descriptive and inferential statistics were used. Correlation analysis is used to check the relationship between the variables, while multiple regression analysis is used to examine the effects of working capital management on profitability of firms. The result reveals that there is a strong negative relationship between variables of working capital management and profitability of Tobacco Industry of Pakistan. This means that as the cash conversion cycle increases, it will lead to declining of firm profitability and managers can create a positive value for shareholders by reducing the cash conversion cycle at optimal level. The study concludes that managers can create value for shareholders by managing the working capital well designed and implemented, and by keeping each components of it at optimal level.

Assessment of Real Time, Multi-Satellite Precipitation Products under Diverse Climatic and Topographic Conditions

Muhammad Masood,Abdul Sattar Shakir,Aftab Hussain Azhar,Guhlam Nabi,Habib-u-Rehman 한국기상학회 2020 Asia-Pacific Journal of Atmospheric Sciences Vol.56 No.4

A preliminary assessment of real-time multi-satellite precipitation products, Global Precipitation Measurement (GPM) IMERG real time (IMRT), TMPA 3B42 real time (TMPA), PERSIANN (PERS) and CMORPH (CMOR) was carried out in Pakistan on entire study area basis and by dividing the study area in to five regions. It is extended from 61o to 77o East and 23.5 o to 37 o North, with varied climatic and topographic conditions. In south coastline along the Arabian Sea, plateaus, deserts and plain areas in the center and in north snow caped mountains. A set of evaluating (continuous) statistical indices, correlation coefficient (CC), bias (Bias), root mean square error (RMSE) and detective (categorical) statistical indices, probability of detection (POD), false alarm ratio (FAR), critical success index (CSI) were applied to evaluate the satellite products against rain gauge data at daily time scales. However CC values were computed at monthly time scale and comparison between average annual values of satellite data and gauge values was also conducted. At annual basis significant resemblance was observed between spatial distribution of satellite and gauge data. At monthly time scale satellite products showed correlation in the range of 0.7 to 0.9 against reference data at major portion of the study area. But at daily time scale a weak correlation from 0.2 to 0.45, higher values of bias and RMSE in hilly terrains with highest average annual rainfall and the adjacent foot hill areas as compared to the plain areas, lower values of POD, CSI and higher values of FAR were observed. An inter comparison among the used satellite products revealed that overall performance of IMRT was better in the study area.