Numerical Investigation on Gas Bubbling Assisted Inclusion Transport and Removal in Multistrand Tundish

Vipul Kumar Gupta,Pradeep Kumar Jha,Pramod Kumar Jain 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.9

In continuous casting, the molten metal quality in the mold is affected by flow pattern, temperature distribution and inclusiontransport in the multistrand tundish. Natural convection due to thermal buoyancy directly influences these parameters andwith gas bubbling, further improvisation can be made. In the present work, numerical investigation of the effect of thermalbuoyancy is carried out to examine the flow field, temperature distribution and inclusion trajectories. Further, gas bubblingcurtain modeling using the Euler-Euler approach is performed for the different locations on the bottom wall of the tundishand quantitative analysis of tundish performance is presented using residence time distribution (RTD) curves. The resultsshow that big circulation loop generated due to thermal buoyancy assists in inclusion removal and mixing at each outlet. Gas bubbling increases the molten metal flow velocity in the central region of tundish, leading to a decrease in the dimensionlessnumber Gr/Re2 near the outlets which are far away from the inlet of the tundish i.e. outlet 2 and outlet 3. Hence, thedominance of natural convection decreases. The inclusion removal rate is found to increase significantly as the circulationloop formed at each side of the curtain forces them upward direction. However, the reported inclusion removal rate in gasbubbling cases is found to be independent of particle size and curtain location.

Root guided implants - a novel approach for the precision placement of immediate implants: A case series

Pramod Kumar(Pramod Kumar ),Prasanth T(Prasanth T ),Satisha TS(Satisha TS ),Nitin Gupta(Nitin Gupta ),Sumita Manandhar(Sumita Manandhar ) 대한치과이식임플란트학회 2022 The Korean Academy of Implant Dentistry Vol.41 No.3

Immediate implant placement is the current modality to provide implant placement following tooth extraction. Immediate implants in posterior multirooted teeth pose challenges in terms of proper angulation and parallelism. Engaging the inter-radicular septal bone provides the advantage of primary stability. Osteotomy site preparation through the septal bone with roots of the natural teeth as a guide provides a precise osteotomy procedure with minimal collateral damage to the adjacent area. This case series aimed to assess the success of immediate implant placement in posterior multirooted teeth using the residual roots as anatomical guides. Three cases of grossly decayed posterior teeth were treated with immediate implant placement. The osteotomy site was prepared using the roots as surgical guides. Implant stability was assessed by resonance frequency analysis (RFA) immediately after placement and 6 months post-op. Healing was uneventful in all cases. Optimal implant stability quotient (ISQ) values of above 70 were achieved, which are suggestive of good primary stability. The desired angulation and parallelism were obtained by utilizing the residual roots as anatomical guides. Six months post-surgically, the patient presented with healthy peri-implant tissue and successful osseointegration. Root-guided implant placement is a novel technique wherein residual roots provide a surgical guide for the placement of immediate implants in multirooted posterior teeth.

Characterization of Cellulose Fiber Extracted from Stems of Myriostachya wightiana (MW) Plants: A Viable Reinforcement for Polymer Composite

Pramod Kumar Parida,Arun Kumar Pradhan,Mihir Kumar Pandit 한국섬유공학회 2023 Fibers and polymers Vol.24 No.2

There is an urgent need to investigate more eco-friendly fibres due to the high cost of traditional cellulosic fibres. Eco-friendlyMW fibre was extracted and characterised as a potential replacement for risky artificial fibre. Physicochemical, XRD, FTIR,SEM, thermal analysis, and Weibull distribution methods were used to study MW fibre as a biocomposite reinforcement. The density, tensile strength, Young's modulus, strain at failure, and micro-fibril angle of MW fibre with an average diameterof 102.278 μm were found to be 1372–1510 kg/m3, 46.554 MPa, 2.442 GPa, 8–9%, and 22 ± 1°, respectively. The predictedYoung's modulus and strength of the fibre showed a good match with the experimental data in the Weibull distributionanalysis. In addition, FTIR verified the presence of cellulose (O = H), hemicellulose (C = O), lignin (C = C), and wax (CC)in the fibre. XRD study reveals CI and CS of 58.07% and 2.86 nm, respectively. The activation energy of 63.156 kJ/mol andthermal stability up to 300 °C were noted during TGA, DTGA, and DSC studies. The fiber's high cellulose content (70 wt%)and roughness (23.664 μ m) contributed to its specific strength and adherence to the polymer matrix. The importance of thepresent study suggests potential applications of this fiber in the fields of papermaking, packaging, lignocellulose composites,and cellulose nanocomposite manufacturing.

Squamous Cell Carcinoma in Exstrophy of the Bladder

Pramod Kumar Sharma,Praveen Kumar Pandey,Mukesh Kumar Vijay,Malay Kumar Bera,Jitendra Pratap Singh,Kaushik Saha 대한비뇨의학회 2013 Investigative and Clinical Urology Vol.54 No.8

Exstrophy of the bladder is a rare congenital anomaly with an incidence of about 1 per 50,000 newborns. The malignant potential of the exstrophied bladder mucosa is well known; 95% are adenocarcinomas, and 3% to 5% are squamous cell carcinomas. Most of the malignant tumors (60%) associated with an exstrophy of the bladder occur during the fourth and fifth decades of life. Of the remaining, about 20% each occur after 60 years and before 40 years. Here we present a case in which squamous cell carcinoma developed in an unrepaired exstrophy of the bladder. We present the management of the case and a brief review of the literature.

Performance evaluation of safety-critical systems of nuclear power plant systems

Kumar, Pramod,Singh, Lalit Kumar,Kumar, Chiranjeev Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.3

The complexity of safety critical systems of Nuclear Power Plant continues to increase rapidly due its transition from analog to digital systems. It has thus become progressively more imperative to model these systems prior to their implementation in order to meet the high performance, safety and reliability requirements. Timed Petri Nets (TPNs) have been widely used to model such systems for non-functional analysis. The paper presents a novel methodology for the analysis of the performance metrics using PN modeling. The paper uses the isomorphism property of the TPNs and the Markov chains for the performance analysis of the safety critical systems. The presented methodology has been validated on a Shutdown System of a Nuclear Power Plant.

Coenzyme Q10: a progress towards the treatment of neurodegenerative disease

Peeyush kumar,Pramod kumar,Alpana ram,Mithilesh kumar,Rajeev kumar 경희대학교 융합한의과학연구소 2010 Oriental Pharmacy and Experimental Medicine Vol.10 No.4

Coenzyme Q10 (CoQ10, or ubiquinone) is an electron carrier of the mitochondrial respiratory chain (electron transport chain) with antioxidant properties. In view of the involvement of CoQ10 in oxidative phosphorylation and cellular antioxidant protection a deficiency in this quinone would be expected to contribute to disease pathophysiology by causing a failure in energy metabolism and antioxidant status. Indeed, a deficit in CoQ10 status has been determined in a number of neuromuscular and neurodegenerative disorders. Primary disorders of CoQ10 biosynthesis are potentially treatable conditions and therefore a high degree of clinical awareness about this condition is essential. A secondary loss of CoQ10 status following HMG-CoA reductase inhibitor (statins) treatment has been implicated in the pathophysiology of the myotoxicity associated with this pharmacotherapy. CoQ10 and its analogue, idebenone, have been widely used in the treatment of neurodegenerative and neuromuscular disorders. These compounds could potentially play a role in the treatment of mitochondrial disorders, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, Friedreich’s ataxia, and other conditions which have been linked to mitochondrial dysfunction. This article reviews the physiological roles of CoQ10, as well as the rationale and the role in clinical practice of CoQ10 supplementation in different neurological diseases, from primary CoQ10 deficiency to neurodegenerative disorders. These will help in future for treatment of patients suffering from neurodegenerative disease.

Cyclic codes from the first class two-prime Whiteman's generalized cyclotomic sequence with order 6

Pramod Kumar Kewat,Priti Kumari 대한수학회 2019 대한수학회보 Vol.56 No.2

Let $p_1$ and $p_2$ be two distinct odd primes with $\mathrm{gcd}(p_1-1,p_2-1)=6$. In this paper, we compute the linear complexity of the first class two-prime Whiteman's generalized cyclotomic sequence (WGCS-I) of order $d=6$. Our results show that their linear complexity is quite good. So, the sequence can be used in many domains such as cryptography and coding theory. This article enrich a method to construct several classes of cyclic codes over $\mathrm{GF}(q)$ with length $n=p_1p_2$ using the two-prime WGCS-I of order 6. We also obtain the lower bounds on the minimum distance of these cyclic codes.

Reconfigurable FIR Filter for Dynamic Variation of Filter Order and Filter Coefficients

Pramod Kumar Meher,Sang Yoon Park 대한전자공학회 2016 Journal of semiconductor technology and science Vol.16 No.3

Reconfigurable finite impulse response (FIR) filters whose filter coefficients and filter order change dynamically during run-time play an important role in the software defined radio (SDR) systems, multi-channel filters, and digital up/down converters. However, there are not many reports on such reconfigurable designs which can support dynamic variation of filter order and filter coefficients. The purpose of this paper is to provide an architectural solution for the FIR filters to support run-time variation of the filter order and filter coefficients. First, two straightforward designs, namely, (i) single-MAC based design and (ii) full-parallel design are presented. For large variation of the filter order, two designs based on (iii) folded structure and (iv) fast FIR algorithm are presented. Finally, we propose (v) high throughput design which provides significant advantage in terms of hardware and/or time complexities over the other designs. We compare complexities of all the five structures, and provide the synthesis results for verification.

Cyclic codes over the ring ${\mathbb F}_p[u,v,w]/\langle u^2, v^2, w^2, uv-vu, vw-wv, uw-wu \rangle$

Pramod Kumar Kewat,Sarika Kushwaha 대한수학회 2018 대한수학회보 Vol.55 No.1

Let $R_{u^2, v^2, w^2, p}$ be a finite non chain ring $ \F_p[u,v,w]\langle u^2,$ $v^2, w^2$, $uv-vu, vw-wv, uw-wu \rangle$, where $p$ is a prime number. This ring is a part of family of Frobenius rings. In this paper, we explore the structures of cyclic codes over the ring $R_{u^2, v^2, w^2, p}$ of arbitrary length. We obtain a unique set of generators for these codes and also characterize free cyclic codes. We show that Gray images of cyclic codes are 8-quasicyclic binary linear codes of length $8n$ over $\F_p$. We also determine the rank and the Hamming distance for these codes. At last, we have given some examples.

Off-Road Machinery System Engineering : Original Article ; Development of a Hopper-Type Planting Device for a Walk-Behind Hand-Tractor-Powered Vegetable Transplanter

( Pramod Chandra Dihingia ),( G. V. Prasanna Kumar ),( Pallab Kumar Sarma ) 한국농업기계학회 2016 바이오시스템공학 Vol.41 No.1

Purpose: In order to ensure that vegetable seedlings (with a soil block around their roots) are planted in an upright orientation after metering in a vegetable transplanter, they need to be dropped freely from a certain height. The walkbehind hand-tractor-powered machines do not have sufficient space to drop the seedlings from that height. In the present work, a hopper-type planting device was developed for the walk-behind hand-tractor-powered vegetable transplanter to ensure that the soil block seedlings are planted in an upright orientation. Methods: Various dimensionless terms were developed based on the dimensional analysis approach, and their effect on the planting of soil block seedlings in an upright orientation (planting efficiency) was studied. The optimum design dimensions of the hopper-type planting device were identified by the Taguchi method of optimization. Results: The ratio of the height of free fall to the sliding distance of the seedling on the surface of the hopper had the highest influence on planting efficiency. The planting efficiency was highest for plants with a height 15 ± 2 cm. The plant handling Froude number, in interaction with the design of the hopper-type planting device, also significantly affected the planting efficiency. Of the hopper design factors, the length of the slide of the seedlings on the surface of the hopper was most important, and induced sufficient velocity and rotation to cause the seedling to fall in an upright orientation. An evaluation of the performance of the planting device under actual field conditions revealed that the planting efficiency of the developed planting device was more than 97.5%. Conclusions: As the seedlings were fed to the metering device manually, an increase in planting rate increased missed plantings. The planting device can be adopted for any vegetable transplanter in which the seedlings are allowed to drop freely from the metering device.