Reduced-complexity local switch based multi-mode QC-LDPC decoder architecture for Gbit wireless communication

Ajaz, S.,Lee, H. IET 2013 Electronics letters Vol.49 No.19

Human hepatic alveolar echinococcosis - medical management of un resectable disease in a resource restrained setting

Ajaz WANI,Dr Sadaf ALI,Omar J. SHAH 한국간담췌외과학회 2021 Annals of hepato-biliary-pancreatic surgery Vol.25 No.-

A Comparative Study on the Thermal Stability of Lignin-PVA Composites Fabricated under Various Lignin Ratios

( Muhammad Ajaz Ahmed ),( Sadaf Mearaj ),( Joon Weon Choi ) 한국목재공학회 2021 한국목재공학회 학술발표논문집 Vol.2021 No.1

In this study the thermal stability of lignin-PVA composites incorporating epichlorohydrin as well as mxene has been investigated. Initially, a set of experiments was designed to screen out the most feasible soda lignin amount to be incorporated into PVA composites. Interestingly, under ambient convective cooling conditions, 10 wt.% soda lignin exhibited quite brittle and transparent characteristic features but without the addition of either any Epichlorohydrin or Mxene. However, upon the addition of Epichlorohydrin a gradual improvement in the physical features such as ductility as well as shape of the lignin-PVA composites was clearly observed. Additionally, a small amount of Mxene, etched from MAX powder, was added and there was a clear elongation and stretchable trend in the lignin-PVA-Mxene composite as compared with only lignin-PVA only composite. Finally, all the fabricated composites were subjected to thermal stability analysis. It was observed clearly that the addition of both the Epichlorohydrin and Mxene improved the thermal stability of the fabricated composites.

Pipeline-Aware QC-IRA-LDPC Code and Efficient Decoder Architecture

Sabooh Ajaz(사부흐),Hanho Lee(이한호) 대한전자공학회 2014 전자공학회논문지 Vol.51 No.10

본 논문은 PIPELINE-AWARE QC-IRA-LDPC (PA-QC-IRA-LDPC) 코드 생성 방법과 Rate-1/2 (2016,1008) PA-QC-IRA-LDPC 코드에 대한 효율적인 고속 복호기 구조를 제안한다. 제안한 방법은 비트 오류율 (BER) 성능 저하 없이 파이프라인 기법을 사용하여 임계경로를 나눌 수 있다. 또한 제안한 복호기 구조는 데이터 처리량, 하드웨어 효율 및 에너지 효율을 크게 향상시킬 수 있다. 제안한 복호기 구조는 90-nm CMOS 기술을 사용하여 합성 및 레이아웃이 수행되었으며, 이전에 보고된 복호기 구조들에 비해서 하드웨어 효율성이 53%이상 향상되었고, 훨씬 좋은 에너지 효율성을 보여준다. This paper presents a method for constructing a pipeline-aware quasi-cyclic irregular repeat accumulate low-density parity-check (PA-QC-IRA-LDPC) codes and efficient rate-1/2 (2016, 1008) PA-QC-IRA-LDPC decoder architecture. A novel pipeline scheduling method is proposed. The proposed methods efficiently reduce the critical path using pipeline without any bit error rate (BER) degradation. The proposed pipeline-aware LDPC decoder provides a significant improvement in terms of throughput, hardware efficiency, and energy efficiency. Synthesis and layout of the proposed architecture is performed using 90-nm CMOS standard cell technology. The proposed architecture shows more than 53% improvement of area efficiency and much better energy efficiency compared to the previously reported architectures.

Macromolecular Prodrugs of Aspirin with HPMC: A Nano Particulate Drug Design, Characterization, and Pharmacokinetic Studies

Muhammad Ajaz Hussain,Khawar Abbas,Muhammad Sher,Muhammad Nawaz Tahir,Wolfgang Tremel,Mohammad Saeed Iqbal,Muhammad Amin,Munair Badshah 한국고분자학회 2011 Macromolecular Research Vol.19 No.12

This article presents the synthesis of novel hydroxypropylmethylcellulose (HPMC)-aspirin (ASP) conjugates,i.e. macromolecular prodrugs, through the reaction of HPMC with ASP after its in situ activation by 4-methylbenzenesulfonyl chloride. The highly pure ASP prodrugs obtained by this homogeneous and elegant esterification method were characterized using different spectroscopic and chromatographic techniques. Nanoparticulate drug design was successfully achieved by the conversion of free hydroxyls of the polymer into acetates. Transmission electron microscopy and scanning electron microscopy showed nanoparticle formation with the major population size distribution of around 450 nm. Nevertheless, the pharmacokinetics of the HPMC conjugates were studied using high performance liquid chromatography. The pharmacokinetic data indicated that a single dose of 132.6 mg of HPMC-ASP was well tolerated in animal studies without any adverse effects. The maximum plasma concentration (C_max) of HPMC-ASP was found to be 14.6 μg·L^-1 with a t_max of 1 h. The plasma half-life and clearance and the volume of HPMC-ASP distribution were 4.6 h, 3.23 L·h^-1, and 21.8 L·kg^-1, respectively. The elimination of HPMC-ASP followed first-order kinetics with r^2 of 0.9643. The results presented in this paper show the great potential of HPMCASP as a more effective, safe, and stable prodrug.

An Area-efficient Half-row Pipelined Layered LDPC Decoder Architecture

Sabooh Ajaz,Tram Thi Bao Nguyen,Hanho Lee 대한전자공학회 2017 Journal of semiconductor technology and science Vol.17 No.6

This paper presents an area-efficient half-row pipelined layered low-density parity check (LDPC) decoder architecture for IEEE 802.11ad applications. The proposed decoder achieves a good tradeoff between throughput and area because of its ability to overcome the low-throughput bottleneck in conventional half-row decoders and the high-complexity bottleneck in fully parallel decoders. Synthesis results using TSMC 40 nm CMOS technology shows much better throughput at 10.84 Gbps and superior area efficiency, compared to previously reported LDPC decoders.

Mild Acidolysis Fractionation of Pinewood Biomass for Lignin Extraction

이자스 ( Muhammad Ajaz Ahmed ),최준원 ( Joon Weon Choi ) 한국목재공학회 2020 한국목재공학회 학술발표논문집 Vol.2020 No.1

Lignocelluloses are the most abundent and readily collectable biomass feedstcoks on this earth and even more with an enough theoratical potential to replace existing fossilfuels based economy. In their typical nature configuration, they are composed of polysaccharides as well as lignin. This lignin is the second most abundant component in their structure and is often a biorefinery waste in a typical 2G bioethanol production schemes. This lignin, actually, is a rich diverse feedstock for the production of various composites, sustainable materials, epoxies and even can be used in medicine and for drug delivery. For this lignin to be isolated with as much little modification as possible is still a challenge for the establishment of lignin-first 2G biorefineries. Therefore, we are trying to adapt and develop such processes that are able to extract/ isolate lignin from the native structure with least and/or no modification. We are applying several organsolv fractionation processes like a green solvent gamma valerolactone (GVL), ethanol, acetone, dioxane and combinations of ethanol, GVL, dioxane and acetone and the synergetic effects of GVL, ethanol under mild acidic and thermal conditions. We have used mild temperature conditions ranging from 50 °C to 90 °C and time ranges from 3 hrs to 6 hrs. In order to induce mild acidic conditions Hcl was employed as a catalyst with few drops only. The lignin fractions separated via this method are subjected to their qualitative analyses such as (Defunctionalization Followed by Random Carbonization) DFRC and Gel permeation chromatography (GPC) to further sort out any clue with their effect on lignin purity and yield.

MXene-Lignin Composites for Energy Harvesting Applications from the Ambient Water

( Ahmed Muhammad Ajaz ),( Joon Weon Choi ) 한국목재공학회 2022 한국목재공학회 학술발표논문집 Vol.2022 No.1

Lignin is the second most abundant biorenewable feedstock available on the earth. This lignin, upon carbonisation, exhibits poor graphene like structure. This structure can be employed for energy harvesting applications. On the other hand, MXene is a new 2D materials that have quite good features in terms of their conductivity within the small pores. A combination under the synergism of MXene and lignin derived activated carbon can be a good possibility to harness energy from ambient environment. Therefore, in this study, lignin derived activated carbon was employed along with Mxene-carbon black composite to study their possibility for harnessing energy from ambient water. First, Mxene was etched via HF method from their MAX phase and its analyses such as FTIR, XRD and SEM images were performed to confirmed its successful formation. Lignin derived activated carbon was subjected to make a composite with Mxene & carbon black to finally fabricate a moisture driven power generator (MDPG) by coating the composite onto cellulosic sheets. Finally, the performance of the as prepared MDPG was measured by determining their open circuit voltage (Voc) and short circuit current (Isc). The highest voltage generation was measured as 750 mV and current as 12 μA employing lignin derived activated carbon & Mxene composite. It was also observed that the application of small amount of water 1 ml successfully initiated the moisture assisted power generation for almost 60 minutes in a one go. From here it can be suggested that the lignin derived activated carbon along with Mxene can be used for energy harvesting applications.

Optimization of twin gear-based pretreatment of rice straw for bioethanol production

Ahmed, Muhammad Ajaz,Rehman, Muhammd Saif Ur,Terá,n-Hilares, Ruly,Khalid, Saira,Han, Jong-In Elsevier 2017 Energy conversion and management Vol.141 No.-

<P><B>Abstract</B></P> <P>A laboratory twin-gear reactor (TGR) was investigated as a new means for the pretreatment of high solid lignocelluloses. Response surface methodology based on Box Behnken Design was used to optimize the enzymatic digestibility with respect to the pretreatment process variables: temperature of 50–90°C, NaOH concentration of 2–6% and no. of cycles of 30–60. The results revealed that the TGR-based pretreatment led to the significant structural alterations through increases in pore size, pore volume, cellulose crystallinity and surface area. SEM images also confirmed the surface modifications in the pretreated rice straw. A response surface quadratic model predicted 90% of the enzymatic digestibility, and it was confirmed experimentally and through the analysis of variance (ANOVA) as well. The TGR extrusion proved to be an effective means for exceedingly high solids lignocellulose.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Twin gear reactor is a continuous high solids pretreatment reactor. </LI> <LI> RSM was applied to optimize twin gear pretreatment for enzymatic digestibility. </LI> <LI> 89% enzymatic digestibility was achieved under optimum conditions. </LI> <LI> Thermomechanical pretreatment altered the structural features of rice straw. </LI> </UL> </P>

Evaluating the Performance of Remotely Sensed Precipitation Estimates against In-Situ Observations during the September 2014 Mega-Flood in the Kashmir Valley

Irfan Rashid,Ajaz Ahmad Parray,Shakil Ahmad Romshoo 한국기상학회 2019 Asia-Pacific Journal of Atmospheric Sciences Vol.55 No.2

In the present study, 4 gridded satellite precipitation data products for September 2014 flood, IMERG (Integrated Multi-satellitE Retrievals for GPM), GSMaP (Global Satellite Mapping of Precipitation), TRMM-3B42 (Tropical Rainfall Measuring Mission) and INSAT-3D-IMR (INSAT Multispectral Rain), were evaluated against the Indian Meteorological Department rain-gauge data from Sep-1st to Sep-7th 2014. Three evaluation indices; Correlation coefficient (CC), the Relative bias (RB) and the Nash- Sutcliffe coefficient (NSC), were used to evaluate the robustness of satellite precipitation estimates with actual rainfall measurements. IMERG precipitation product has a near perfect positive CC and NSC values of 0.94 and 0.99 respectively; while the CC and NSC values are 0.7 and 0.5 for GSMaP_Gauge; 0.69 and 0.05 for INSAT-3D-IMR; and 0.9 and 0.8 for TRMM-3B42 respectively. The RB estimates indicate that IMERG, with a bias of 2%, is a best-fit dataset when compared to the surface raingauge observations. In contrast, TRMM-3B42, GSMaP and INSAT-3D-IMR have underestimation biases of −31%, −58%, and − 86%respectively. Analysis of the indices indicates that IMERG precipitation product performed better than other three satellite precipitation products owing to the closeness of values with surface gauge station data over Kashmir. Owing to scanty observation of rainfall in the region, IMERG has a potential to become a cost effective input data source for designing a flood early warning system (FEWS) for Kashmir. However, it is suggested to evaluate the robustness of different satellite-derived precipitation estimates compared to rain gauge observations by incorporating more extreme events from different mountain regions globally for establishing the best satellite derived precipitation product.