GREY-FUZZY TAGUCHI APPROACH FOR MULTI-OBJECTIVE OPTIMIZATION OF PERFORMANCE AND EMISSION PARAMETERS OF A SINGLE CYLINDER CRDI ENGINE COUPLED WITH EGR

S. ROY,A. K. DAS,R. BANERJEE 한국자동차공학회 2016 International journal of automotive technology Vol.17 No.1

The present study attempts to address the challenges of the multiobjective optimization problem of the BSFCNOx- PM trade-off paradox of an existing diesel engine by harnessing the synergetic benefit of PM and BSFC reduction through CRDI operation and simultaneous NOx reduction by EGR application. Load, FIP and EGR were chosen as the input parameters while NOx, PM and BSFC were the response variables. In order to reduce the experimental effort, the Taguchi L16 orthogonal array technique was employed to obtain the corresponding values of the response variables. The grey relational analysis coupled with fuzzy logic has been employed as the optimization routine. The optimal combination of the input parameters corresponding to the calibrated values of the response variables were obtained by employing the Grey-Fuzzy Grade and S-N ratio strategy as a performance index. The computed optimal combination so obtained were further validated through actual experimentation. EGR was found to be the most influencing factor in the present optimization endeavour. The study also established that the Grey-Fuzzy-Taguchi method was not only comparable but superior to the Grey-Taguchi method usually employed for such optimization studies.

Evaluation of the Pentacam Ray Tracing Method for the Measurement of Central Corneal Power After Myopic Photorefractive Keratectomy

Oh, Jong-Hyun,Kim, Sung Hyun,Chuck, Roy S.,Park, Choul Yong Masson Pub. USA 2014 Cornea Vol.33 No.3

PURPOSE:: The study evaluated the ray tracing method [total corneal refractive power (TCRP)] in a Pentacam apparatus (Oculus, Wetzlar, Germany) for postoperative keratometry measurement after myopic photorefractive keratectomy (PRK). METHODS:: Manifest refraction (MR) and Pentacam analyses were performed preoperatively and at 6 months postoperatively after the PRK (STAR S4 IR CustomVue; Abbott Medical Optics/Visx) in 49 right eyes from 49 patients (age, 25.42 ± 3.51 years). Postoperative corneal power was calculated using the clinical history method (CHM) and compared with postoperatively measured simulated keratometry (simK), true net power (TNP) at 3 mm, and pupil-centered TCRP at the center, 1, 3, and 4 mm (TCRP0, TCRP1, TCRP3, and TCRP4). Vertex-distance-adjusted refractive change (delta-MR) at the corneal plane was also compared with various keratometric changes (delta-K). RESULTS:: Postoperative TCRP0, TCRP1, TCRP3, and TCRP4 showed no significant difference compared with that of the CHM. Postoperative simK was significantly higher than that of the CHM, whereas the TNP was significantly lower compared with that of the CHM. The delta-Ks measured by simK, TNP, and TCRPs were significantly smaller than delta-MR, and delta-TCRP4 showed the least difference [mean ± SD, 0.28 ± 0.55 diopters (D)] with delta-MR. The 95% limit of agreement between delta-MR and delta-TCRP4 was −0.85 to 1.31 D. The difference between delta-TCRP4 and delta-MR was <0.5 D in 55.1% and <1.0 D in 87.8% of the eyes studied. CONCLUSIONS:: Although postoperative TCRPs showed no significant difference with CHM, delta-MR was still underestimated after myopic PRK.

Recrystallization of Copper Films Deposited by Pulsed Electroplating on the ECR Plasma-Cleaned Copper Seed Layers

Dukryel Kwon,Hyunah Park,Chongmu Lee,H. T. Jeon,S Ghosh,Sudipta Roy 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.44 No.52

Cu seed layers deposited by magnetron sputtering onto tantalum nitride barrier lms were treated with an electron cyclotron resonance (ECR) plasma to enhance Cu nucleation prior to Cu electroplating. Then, the copper lms were electroplated and annealed by rapid thermal annealing (RTA) or rapid thermal nitridation (RTN) at various temperatures ranging from 200 to 500 C. The eects of annealing on the copper lms electroplated on the hydrogen ECR plasma cleaned copper seed layers were investigated using X-ray diraction (XRD), electron back-scattered diraction (EBSD), and atomic force microscopy (AFM). It appears that the copper lm undergoes complete recrystallization during annealing at a temperature higher than 400 C. The resistivity of the Cu lm tends to decrease and the degree of (111) preferred orientation tends to increase as the annealing temperature increases. The optimum annealing condition for obtaining the lm with the lowest resistivity, the smoothest surface, and the highest degree of the (111) preferred orientation is rapid thermal nitriation (RTN) at 400 C for 120 s. The resistivity and the surface roughness of the electroplated copper lm annealed under this condition are 1.98 -cm and 17.77 nm, respectively.

Pose Estimation of 5-DOF Manipulator using On-Body Markers

Sree S. S. Katta,Adnan J.,S. Chaudhary,S. Dutta Roy,Chetan Arora,S. K. Saha,Magid E. 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

Manipulators are helpful in performing various hazardous tasks like sanitization with chemicals in germs infected areas, spraying pesticides in fields, pick and place of heavy and hazardous materials where direct human intervention is difficult. For manipulators to perform its assigned task accurately, prior estimation of its pose needs to be pinpointed. End-effector grasping and arm manipulation require estimation of 3D object poses. Recently, a number of procedures and databases for vision-based estimation of object pose have been advised. However, it is not clear about the performance of the developed algorithms for visual pose estimation of robot manipulation. In this paper we present the pose estimation of a 5-dof PhantomX Reactor Arm using On-Body/Aruco Markers. Forward and inverse kinematics were used to estimate the pose from the position coordinates calculated using computer vision techniques. This paper implements an approach aimed at estimating the pose of a camera, affixed to a robotic manipulator, against a target object. We adopt a single camera single-shot technique that minimizes the reprojection error over all the rigid poses. The simulation and experimental results using industrial monocular camera for different sizes of On-body markers were presented.

Hierarchical free-standing networks of MnCo₂S₄ as efficient Electrocatalyst for oxygen evolution reaction

Jadhav, Harsharaj S.,Roy, Animesh,Thorat, Gaurav M.,Chung, Wook-Jin,Seo, Jeong Gil Elsevier 2019 Journal of industrial and engineering chemistry Vol.71 No.-

<P><B>Abstract</B></P> <P>The development of highly efficient, stable and cost-effective electrocatalyst for oxygen evolution reaction (OER) is critical. Herein, we report growth of MnCo<SUB>2</SUB>S<SUB>4</SUB> flakes on SS-mesh using two-step strategy, and used as an efficient, highly active and stable electrocatalyst for OER under alkaline condition. The free-standing electrocatalyst delivers exceptional stability of 100h and activity for OER with overpotential of 290mV at a current density of 10mAcm<SUP>−2</SUP> in 1M KOH. The enhanced electrocatalytic performance was supported experimentally by electrochemical impedance spectra and measurement of the electrochemically active surface area. The high electrochemical active surface area and electrical conductivity of MnCo<SUB>2</SUB>S<SUB>4</SUB> flakes played an essential role in their high electrocatalytic performance.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MnCo<SUB>2</SUB>S<SUB>4</SUB> have been synthesized by electrodeposition followed by sulfidation. </LI> <LI> Electrocatalyst exhibits overpotential of 290mV at a 10mA/cm<SUP>2</SUP> current density. </LI> <LI> Large ECSA with plenty active sites deliver exceptional stability of 100h. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The free-standing electrocatalyst demonstrates superior activity over that of a oxide catalyst, with the need of an overpotential of 290mV to drive a geometrical catalytic current density of 10mAcm<SUP>−2</SUP> in 1M KOH, which is superior to earlier report of MnCo<SUB>2</SUB>S<SUB>4</SUB>.</P> <P>[DISPLAY OMISSION]</P>

Recurrent Aphthous Stomatitis in the Diagnosis of Behcet's Disease

Rogers, .III Roy S. Yonsei University, College of Medicine 1997 Yonsei medical journal Vol.38 No.6

Staining-free cell viability measurement technique using lens-free shadow imaging platform

Roy, M.,Jin, G.,Pan, J.H.,Seo, D.,Hwang, Y.,Oh, S.,Lee, M.,Kim, Y.J.,Seo, S. Elsevier Sequoia 2016 Sensors and actuators. B Chemical Vol.224 No.-

Tests for cell viability, i.e., an assay quantifying the ratio of viable cells or tissues over the total cells or tissues within an index between 0 and 1 (or 0 and 100%), play an important role in cell or tissue culturing procedures. The viability test result, varying with several biological factors such as mechanical activity, motility, contraction, or mitotic activity of cells or tissues, is a crucial indicator in cell related research protocols including toxicity and anabolic activity assays. There are several well-established methods for evaluating cell viability, such as trypan blue assay, propidium iodide assay, 7-aminoactinomycin D assay and resazurin and formazan (MTT/XTT) assay. However, most of these methods determine viability using stained cell samples, which intern affect the cells morphology eventually making it unable to keep culturing the specimen. To address this issue, we have developed a novel shadow imaging technique to capture the diffraction patterns (shadow patterns) of micro objects without the use of any staining reagent. In this paper, we introduce a shadow imaging platform that can determine cell viability of more than 3000 human cancer cells immediately with a single digital image. Our custom-built lens-free shadow imaging platform consists of a compact, cost-effective light source, i.e., a light-emitting diode, and an optoelectronic image recording device, i.e., a complementary metal-oxide semiconductor image sensor. Three types of human cancer cell lines (Caco-2, HepG2, and MCF7) were incubated in 24-well plates, and H<SUB>2</SUB>O<SUB>2</SUB> was added to track and compare the cell viability at each concentration tested. We obtained high correlation indices, with a minimum of 0.94, between the MTT assay and the shadow imaging platform. All these characterizations were done by custom developed automated detection algorithm. This algorithm analyzes the various elements of the diffraction pattern (shadow image), such as pixel intensity and connected pixel numbers, and counts the viable cells automatically, allowing the cell viability to be determined easily and immediately in a staining-free manner.

Anti-inflammatory activity of aqueous methanolic extract of Swietenia mahagoni (L.) Jacq. (Meliaceae) leaves

Roy S,Banerjee B,Mukherjee J,Besra SE,Vedasiromoni JR 경희대학교 융합한의과학연구소 2009 Oriental Pharmacy and Experimental Medicine Vol.9 No.1

Pharmacological investigations were carried out with aqueous methanolic extract (AME) of Swietenia mahagoni (L.) Jacq. (Meliaceae) leaves. Acute toxicity studies revealed that the LD50 dose of AME was 600 mg/kg, i.p. AME was found to possess significant anti-inflammatory activity in acute, sub-chronic and chronic models of inflammation. AME selectively inhibited cyclooxygenase (COX)-2 activity, which is involved in arachidonic acid metabolism and biosynthesis of prostaglandins under inflammatory conditions. Treatment with AME significantly enhanced total peritoneal cell count and the number of macrophages in normal mice, which revealed that AME may also alter the immune response along with its anti-inflammatory effect. The saponins or the alkaloids present in AME may be responsible for the anti-inflammatory activity. Pharmacological investigations were carried out with aqueous methanolic extract (AME) of Swietenia mahagoni (L.) Jacq. (Meliaceae) leaves. Acute toxicity studies revealed that the LD50 dose of AME was 600 mg/kg, i.p. AME was found to possess significant anti-inflammatory activity in acute, sub-chronic and chronic models of inflammation. AME selectively inhibited cyclooxygenase (COX)-2 activity, which is involved in arachidonic acid metabolism and biosynthesis of prostaglandins under inflammatory conditions. Treatment with AME significantly enhanced total peritoneal cell count and the number of macrophages in normal mice, which revealed that AME may also alter the immune response along with its anti-inflammatory effect. The saponins or the alkaloids present in AME may be responsible for the anti-inflammatory activity.

Bandwidth enlargement of CMOS TIA using on-chip T-network for patient diagnosis in biomedical application

Roy, G.M.,Kumar, S.,Kanuajia, B.K.,song, H. Mackintosh Publications] 2017 Microelectronics journal Vol.67 No.-

<P>This work concerns on CMOS based trans-impedance amplifier (TIA) where enhancing the bandwidth by using optimized on-chip T-network for biomedical diagnosis applications. The proposed TIA consists of inductive peaking components as an input stage, distributed amplifier with feedback loop as middle stage while output as T-network. The proposed TIA with T-network achieves much wide band operation within range of 4.8-19.6 GHz. As compared to conventional TIA, additional trans-impedance bandwidth of 1.4 GHz in the lower band while 9.1 GHz in higher band are able to achieve for the proposed design. The proposed architectures are implemented into ADS platform using commercial 65 nm TSMC process. With this proposed technique, TIA also succeeds lower bit error rate (BER) for high speed data transmission in optical receiver i.e. beneficial towards the biomedical diagnosis. Chip fabrication of proposed TIA consuming less power of 10.8 mW from the power supply of 1.6 V. Measured and simulated data exhibits a wide bandwidth operation with trans-impedance gain of 55dBOand made good correlation with each other. Moreover, experimental BER demonstrates less than 10-11 by providing pseudorandom bit sequence at 6-11 Gb/s within desired band of operation in TIA. The optimized on-chip T-network occupies only 10% of the whole chip area of 0.4 mm(2).</P>

Anti-Alzheimer's disease potential of coumarins from Angelica decursiva and Artemisia capillaris and structure-activity analysis

Ali, Md.Y.,Jannat, S.,Jung, H.A.,Choi, R.J.,Roy, A.,Choi, J.S. Elsevier 2016 Asian Pacific journal of tropical medicine Vol.9 No.2

<P>Objective: To use structure-activity analysis to study the anti-Alzheimer's disease (anti-AD) activity of natural coumarins isolated from Angelica decursiva and Artemisia capillaries, along with one purchased coumarin (daphnetin). Methods: Umbelliferone, umbelliferone 6-carboxylic acid, scopoletin, isoscopoletin. 7-methoxy coumarin, scoparone, scopolin, and esculetin have been previously isolated; however 2'-isopropyl psoralene was isolated from Angelica decursiva for the first time to evaluate their inhibitory effects against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) enzyme activity. We scrutinized the potentials of coumarins as cholinesterase and BACE1 inhibitors via enzyme kinetics and molecular docking simulation. Results: Among the test compounds, umbelliferone 6-carboxylic acid, esculetin and daphnetin exhibited potent inhibitory activity against AChE, BChE and BACE1. Both esculetin and daphnetin have a catechol group and exhibit significant anti-AD activity against AChE and BChE. In contrast, presence of a sugar moiety and methoxylation markedly reduced the anti-AD activity of the coumarins investigated in this study. With respect to BACE1 inhibition, umbelliferone 6-carboxylic acid, esculetin and daphnetin contained carboxyl or catechol groups, which significantly contributed to their anti-AD activities. To further investigate these results, we generated a 3D structure of BACE1 using Autodock 4.2 and simulated binding of umbelliferone 6-carboxylic acid, esculetin and daphnetin. Docking simulations showed that different residues of BACE1 interacted with hydroxyl and carboxylic groups, and the binding energies of umbelliferone 6-carboxylic acid, esculetin and daphnetin were negative (-4.58, -6.25 and -6.37 kcal/mol respectively). Conclusions: Taken together, our results suggest that umbelliferone 6-carboxylic acid, esculetin and daphnetin have anti-AD effects by inhibiting AChE, BChE and BACE1, which might be useful against AD.</P>