Bandwidth Efficient Adaptive Forward Error Correction Mechanism with Feedback Channel

Farhan Azmat Ali,Pieter Simoens,Wim Van de Meerssche,Bart Dhoedt 한국통신학회 2014 Journal of communications and networks Vol.16 No.3

Multimedia content is very sensitive to packet loss and therefore multimedia streams are typically protected against packet loss, either by supporting retransmission requests or by adding redundant forward error correction (FEC) data. However, the redundant FEC information introduces significant additional bandwidth requirements, as compared to the bitrate of the original video stream. Especially on wireless and mobile networks, bandwidth availability is limited and variable. In this article, an adaptive FEC (A-FEC) system is presented whereby the redundancy rate is dynamically adjusted to the packet loss, based on feedback messages from the client. We present a statistical model of our A-FEC system and validate the proposed system under different packet loss conditions and loss probabilities. The experimental results show that 57?5%bandwidth gain can be achieved compared with a static FEC approach.

Cross-Layer Reduction of Wireless Network Card Idle Time to Optimize Energy Consumption of Pull Thin Client Protocols

Simoens, Pieter,Ali, Farhan Azmat,Vankeirsbilck, Bert,Deboosere, Lien,Turck, Filip De,Dhoedt, Bart,Demeester, Piet,Torrea-Duran, Rodolfo,Perre, Liesbet Van der,Dejonghe, Antoine The Korea Institute of Information and Commucation 2012 Journal of communications and networks Vol.14 No.1

Thin client computing trades local processing for network bandwidth consumption by offloading application logic to remote servers. User input and display updates are exchanged between client and server through a thin client protocol. On wireless devices, the thin client protocol traffic can lead to a significantly higher power consumption of the radio interface. In this article, a cross-layer framework is presented that transitions the wireless network interface card (WNIC) to the energy-conserving sleep mode when no traffic from the server is expected. The approach is validated for different wireless channel conditions, such as path loss and available bandwidth, as well as for different network roundtrip time values. Using this cross-layer algorithm for sample scenario with a remote text editor, and through experiments based on actual user traces, a reduction of the WNIC energy consumption of up to 36.82% is obtained, without degrading the application's reactivity.

Cross-Layer Reduction of Wireless Network Card Idle Time to Optimize Energy Consumption of Pull Thin Client Protocols

Pieter Simoens,Farhan Azmat Ali,Bert Vankeirsbilck,Lien Deboosere,Filip De Turck,Bart Dhoedt,Piet Demeester,Rodolfo Torrea-Duran,Liesbet Van der Perre,Antoine Dejonghe 한국통신학회 2012 Journal of communications and networks Vol.14 No.1

Thin client computing trades local processing for network bandwidth consumption by offloading application logic to remote servers. User input and display updates are exchanged between client and server through a thin client protocol. On wireless devices, the thin client protocol traffic can lead to a significantly higher power consumption of the radio interface. In this article, a cross-layer framework is presented that transitions the wireless network interface card (WNIC) to the energy-conserving sleep mode when no traffic from the server is expected. The approach is validated for different wireless channel conditions, such as path loss and available bandwidth, as well as for different network roundtrip time values. Using this cross-layer algorithm for sample scenario with a remote text editor, and through experiments based on actual user traces, a reduction of the WNIC energy consumption of up to 36.82% is obtained, without degrading the application’s reactivity.

EAR: Enhanced Augmented Reality System for Sports Entertainment Applications

( Zahid Mahmood ),( Tauseef Ali ),( Nazeer Muhammad ),( Nargis Bibi ),( Imran Shahzad ),( Shoaib Azmat ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.12

Augmented Reality (AR) overlays virtual information on real world data, such as displaying useful information on videos/images of a scene. This paper presents an Enhanced AR (EAR) system that displays useful statistical players’ information on captured images of a sports game. We focus on the situation where the input image is degraded by strong sunlight. Proposed EAR system consists of an image enhancement technique to improve the accuracy of subsequent player and face detection. The image enhancement is followed by player and face detection, face recognition, and players’ statistics display. First, an algorithm based on multi-scale retinex is proposed for image enhancement. Then, to detect players’ and faces’, we use adaptive boosting and Haar features for feature extraction and classification. The player face recognition algorithm uses boosted linear discriminant analysis to select features and nearest neighbor classifier for classification. The system can be adjusted to work in different types of sports where the input is an image and the desired output is display of information nearby the recognized players. Simulations are carried out on 2096 different images that contain players in diverse conditions. Proposed EAR system demonstrates the great potential of computer vision based approaches to develop AR applications.

Ga-doped GZO graded ITO electrodes with enhanced electron extraction for perovskite solar cells

Hae-Jun Seok,Azmat Ali,Jung-Hwa Seo,Hyun-Hwi Lee,Na-Eun Jung,Yeon-Jin Yi,Han-Ki Kim 한국진공학회 2019 한국진공학회 학술발표회초록집 Vol.2019 No.8

ZnO:Ga-graded ITO electrodes to control interface between PCBM and ITO in planar perovskite solar cells

Seok, Hae-Jun,Ali, Azmat,Seo, Jung Hwa,Lee, Hyun Hwi,Jung, Na-Eun,Yi, Yeonjin,Kim, Han-Ki unknown 2019 SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS Vol.20 No.1

<P><B>ABSTRACT</B></P><P>Ga-doped ZnO (GZO)-graded layer, facilitating electron extraction from electron transport layer, was integrated on the surface of transparent indium tin oxide (ITO) cathode by using graded sputtering technique to improve the performance of planar n-i-p perovskite solar cells (PSCs). The thickness of graded GZO layer was controlled to optimize GZO–indium tin oxide (ITO) combined electrode for planar n-i-p PSCs. At optimized graded thickness of 15 nm, the GZO–ITO combined electrode showed an optical transmittance of 95%, a resistivity of 2.3 × 10<SUP>−4</SUP> Ohm cm, a sheet resistance of 15.6 Ohm/square, and work function of 4.23 eV, which is well matched with the 4.0-eV lowest unoccupied molecular orbital of [6,6]-phenyl-C<SUB>61</SUB>-butyric acid methyl ester. Owing to enhanced extraction of electron by the graded GZO, the n-i-p PSC with GZO–ITO combined electrode showed higher power conversion efficiency (PCE) of 9.67% than the PCE (5.25%) of PSC with only ITO electrode without GZO-graded layer. In addition, the GZO integrated-ITO electrode acts as transparent electrode and electron extraction layer simultaneously due to graded mixing of the GZO at the surface region of ITO electrode.</P>

Seasonal Influence on Postoperative Complications after Total Knee Arthroplasty

Azeem Tariq Malik,Shahid Khan Azmat,Arif Ali,Syed Hamza Mufarrih,Shahryar Noordin 대한슬관절학회 2018 대한슬관절학회지 Vol.30 No.1

Purpose: This study is aimed at investigating whether inpatient complications and surgical site infections (SSIs) occurred more commonly in patients undergoing total knee arthroplasty (TKA) during the summer season. Materials and Methods: A total of 725 patients who underwent unilateral or bilateral TKA were included in this study. A total of 241 patients (33.2%) underwent TKA between May and August. Our outcomes of interest were the incidence of postoperative complications and length of stay. Results: May–August surgeries were associated with a higher risk of postoperative inpatient complications (p=0.003). May–August surgeries (odds ratio [OR], 2.13; 95% confidence interval [CI], 1.18 to 3.85), postoperative transfusion (OR, 2.46; 95% CI, 1.43 to 4.26), postoperative special care unit stay (OR, 4.68; 95% CI, 1.99 to 11.0) and chronic kidney disease (OR, 3.27; 95% CI, 1.15 to 9.28) were associated with a higher odds of developing inpatient complications. No association was present between summer surgeries and SSIs (p=0.486). Conclusions: The results of this study show that overall complication rates following TKA exhibit a seasonal trend, with a peak during the summer months. These results may have some implication in clinical practice and stricter approaches to hospital guidelines during the summer months.

Outcomes of Large Volume Paracentesis in Cirrhotic Patients with Spontaneous Bacterial Peritonitis

( Hafiz Abdul Basit Siddiqui ),( Muhammad Tahir Khan ),( Hasnain Ali Shah ),( Rabeea Azmat ),( Saad Bin Zafar ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims & Background: Bacterial infections are one of the most frequent complication in cirrhosis, particularly in patients with decompensated cirrhosis and accounts for significant mortality. Ascites is one of the most common complications of hepatic cirrhosis (1). In a country like Pakistan where the prevalence of Hepatitis C is on the rise, end stage liver disease is becoming a common scenario (2-4). Spontaneous bacterial peritonitis (SBP) occurs in 10-30% of such patients and is associated with high mortality rate among hospitalized patients (1, 5-7). The diagnosis of SBP through paracentesis is crucial in the management of SBP. SBP should be diagnosed early as for successful treatment of patients. Diagnostic paracentesis facilitates rapid initiation of antimicrobial therapy and permits optimal coverage in case a causative organism identified. However, more recently, the role of paracentesis in management of SBP is also explored through large volume removal of ascitic fluid. Despite the proposed risk of renal failure, Large Volume Paracentesis (LVP) among SBP patients has shown promising results indicated by lesser morbidity and mortality (8). Rationale of the study: Spontaneous bacterial peritonitis is a serious infectious condition with grave outcome in cirrhotic patients. Large volume paracentesis decreases the burden of infective fluid causing further deterioration of condition. Outcomes of LVP in SBP patients are not clearly addressed in previous studies. Furthermore, to date, no study from the country has reported the effect of large volume paracentesis on the management of SBP in hospitalized patients. This study will assess the outcomes of LVP in patients with SBP, both in terms of length of stay, in hospital 6 week mortality. Objectives: To compare the treatment outcomes among patients with and without large volume paracentesis diagnosed with Spontaneous Bacterial Peritonitis Methods: Study design: Analytical Cross-sectional Study Setting: Gastroenterology Unit, The Aga Khan University Hospital, Karachi Study Duration: 2 Years Study population: Patients admitted with Spontaneous Bacterial Peritonitis to Gastroenterology Unit, the Aga Khan University Hospital Sample Size: Using OpenEpi.com online sample size calculator and using the differences in hospital stay among patients with and without delayed paracentesis as 36.84% and 21.48% (8) the sample size was calculated to be 200 at 95% confidence level (100 in each group). Sampling Technique: Consecutive Sampling Inclusion Criteria: Patients admitted with ascites found to have spontaneous bacterial peritonitis on diagnostic paracentesis. 1) Patients with complete records 2) Above 18 and below 75 years of age Exclusion criteria: 1) Incomplete records 2) Secondary peritonitis Data Collection: The data will be extracted from the records and information analyzed will be patient age, gender, whether the patients receive large volume paracentesis or not, the length of hospital stay, and length of ICU stay. No patient will be enrolled for the study and retrospective data analysis will be carried out. Conclusions: Extracted data till now favours that LVP in patients with SBP translates into significantly positive outcomes in terms of length of hospital stay, spcecial care unit stay, need for terlipressin infusions, in hosptial mortality and 6 weeks mortality post large volume paracentesis. Hence LVP shoiuld be performed in patients suffering from SBP.