MULTI-ITEM SHELF-SPACE ALLOCATION OF BREAKABLE ITEMS VIA GENETIC ALGORITHM

MAITI, MANAS KUMAR,MAITI, MANORANJAN 한국전산응용수학회 2006 Journal of applied mathematics & informatics Vol.20 No.1

A general methodology is suggested to solve shelf-space allocation problem of retailers. A multi-item inventory model of breakable items is developed, where items are either complementary or substitute. Demands of the items depend on the amount of stock on the showroom and unit price of the respective items. Also demand of one item decreases (increases) due to the presence of others in case of substitute (complementary) product. For such a model, a Contractive Mapping Genetic Algorithm (CMGA) has been developed and implemented to find the values of different decision variables. These are evaluated to have maximum possible profit out of the proposed system. The system has been illustrated numerically and results for some particular cases are derived. The results are compared with some other heuristic approaches- Simulated Annealing (SA), simple Genetic Algorithm (GA) and Greedy Search Approach (GSA) developed for the present model.

Design of Single Cell Membrane Shape and Array Configuration for MEMS Based Micromachined Ultrasonic Sensor to Improve the Performance: A Three Dimensional Model Characterization

Reshmi Maity,N. P. Maity,Srinivasa Rao Karumuri,Girija Sravani,K. Guha 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.6

The output acoustic energy of a capacitive micromachined ultrasonic transducer (CMUT) can be enhanced by adjusting its membrane structure. In this paper three dissimilar membranes shapes of CMUT: circular, rectangular and hexagonal, were aimed and 3D finite element method simulated using adaptive meshing technique. The displacement as well as strain and stress outputs for a single membrane and an array of four membranes on a single substrate were obtained. The simulated results are supported by analytical modeling. A static bias of 40 V and a signal of amplitude 100 mV are employed. A pressure of 8603.98 N/m 2 resulting in a force of 16.894 μN was applied at the membrane. Fixtures were provided on every possible face of the structure except the face 1 (membrane). The outcomes showed that the membrane displacement is highest for a circular geometry under same uniform pressure and area of vibration. Moreover as the distance between the elemental membranes increases the displacement decreases for circular and hexagonal membranes while the reverse behavior is observed for rectangular membranes.

Fringing Capacitive Effect of Silicon Carbide Based Nano-Electro-Mechanical-System Micromachined Ultrasonic Transducers: Analytical Modeling and FEM Simulation

Reshmi Maity,N. P. Maity,K. Srinivasa Rao,Girija Sravani,K. Guha,S. Baishya 한국전기전자재료학회 2019 Transactions on Electrical and Electronic Material Vol.20 No.5

This paper models the fringing fi eld eff ects in a capacitive micromachined ultrasonic transducer (CMUT) structure for determining the sensitivity of the device. CMUT is used as a medical imaging component which can be an important module for sustainable healthcare system. The capacitance value of the device is evaluated based on Younes Ataiiyan’s method. To determine the equivalent capacitance of the device, the capacitances of the membrane, gap and silicon nitride insulating layer are associated in series. Mason’s modeling techniques are used to evaluate the membrane displacement. Circular membrane approximation model has been considered. Eff ects of the variation in membrane thickness, gap separation, and membrane radius on membrane displacement are investigated. The analytical prediction has been validated with the finite element method simulation results through PZFlex. Three dimensional modeling is carried out to accurately capture the characteristic behavior of the device. The agreements of both results are excellent which verifi es that fringing field effects exist in the device operation.

Effects of Hafnium Oxide on Surface Potential and Drain Current Models for Subthreshold Short Channel Metal–Oxide–Semiconductor-Field-Effect-Transistor

N. P. Maity,Reshmi Maity,Subir Dutta,Subhasish Deb,K. Girija Sravani,K. Srinivasa Rao,S. Baishya 한국전기전자재료학회 2020 Transactions on Electrical and Electronic Material Vol.21 No.3

Surface potential and drain current models for a physically based double halo metal–oxide–semiconductor-fi eld-eff ect-transistor(MOSFET) are reported. The proposed models have been established in sub-threshold mode of MOSFET operation. The depletion layer depth used in the pseudo two dimensional Poisson’s equation comprises the effect of two symmetrical pocket implantations at both the ends of the channel region. In this effort, improvement in the investigation is brought in by taking lateral asymmetric channel owing to non-uniform doping. The conventional silicon-dioxide (SiO2) material is replaced with a promising high-k dielectric material hafnium oxide (HfO2) to analyze the surface potential and drain current models. Analytical results have been compared using Synopsys technology computer aided design (TCAD). Excellent conformities between the analytical models and simulations are observed.

Design of a Non-uniform Serpentine Asymmetric Cantilever RF-MEMS Shunt Capacitive Switch for RADAR Applications

Ch. Gopichand,Reshmi Maity,N. P. Maity,K. Srinivasa Rao,Koushik Guha,Santanu Maity,Ameen Eisnawi 한국전기전자재료학회 2020 Transactions on Electrical and Electronic Material Vol.21 No.4

This paper presents the design and simulation of Cantilever type RF-MEMS Capacitive shunt switch with meanders and perforations. The main objective of this paper is to reduce the pull-in voltage and increases isolation of the proposed switch. Electro-mechanics and Solid-mechanics are used to simulate the proposed switch by using COMSOL Multiphysics software. The capacitance, switching time, stress analysis are calculated and compare both theoretical and simulation results of the proposed switch. By varying diff erent beam thickness, materials, an air gap between the beam and signal line to calculate spring constant and pull-in voltage. The proposed switch having pull-in voltage is 1.371 V, the dielectric material Si 3 N 4 is to improve the capacitance analysis of the switch. The up and downstate capacitance is 7.073 fF, 1.259 pF. The RF performance is simulated by using Ansoft HFSS tool, the switch performs at low frequencies at 1–4 GHz range. The return (S 11 ) and insertion loss (S 12 ) of the proposed switch is − 30 dB, − 0.0516 dB and the switch having good isolation (S 21 ) is − 37.5 dB at 1.5 GHz frequency. The switch is suitable for radar and satellite communication applications.

Low Pull-in-Voltage RF-MEMS Shunt Switch for 5G Millimeter Wave Applications

P. Ashok Kumar,K. Srinivasa Rao,B. Balaji,M. Aditya,N. P. Maity,Reshmi Maity,Santanu Maity,Ameen El Sinawi,Koushik Guha,K. Girija Sravani 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.6

RF MEMS switches have been employed in many commercial and defense applications due to their high potentiality at microwave and millimeter wave frequencies. In this paper, an RF MEMS shunt switch is designed with perforations and without perforations and simulated using iterative meanders for millimeter wave 5G applications. The proposed iterative meander offers a low spring-constant of 0.68 N/m and reduces the pull-in-voltage upto 1.8 V. The proposed perforated switch design is more reliable which operates with less transition time of 11.2 μs with a quality factor of 1.69. The switch possesses high capacitance ratio of 63. During ON condition, the switch shows low insertion loss of − 0.24 dB at 41 GHz and high isolation of − 46.7 dB at 38 GHz. The performance of the switch is analyzed by simulating it using COMSOL Multiphysics 5.2v (FEM tool). The obtained simulation results shows close approximation with the theoretical results and the switch is efficiently used for 5G millimeter wave applications.

Improvement of the metabolic stability of pan-RAF/VEGFR2 dual inhibitors

Maiti Santanu,권정희,홍성표,권호석,김진호,안순길 대한화학회 2023 Bulletin of the Korean Chemical Society Vol.44 No.11

Development of dual inhibitors of pan-RAF/VEGFR2 is important for the treatment of K-Ras mutated colorectal cancer, which is one of the most common and lethal malignancies. Building upon our studies in dual inhibitors of pan-RAF/VEGFR2, we designed and synthesized new dual inhibitor candidates by installing a urea or guanidine moiety to the previously reported dual inhibitors in order to enhance both metabolic stability and solubility. Various 1-(5-((3-(9H-purin-6-yl)pyridin-2-yl)amino)-2-fluorophenyl)-3-phenylurea and 1-(5-((3-(9H-purin-6-yl)pyridin-2-yl)amino)-2-fluorophenyl)-3-phenylguanidine derivatives were synthesized, and their antiproliferative activities against LS513 cell (K-RasG12D) and VEGFR2 were evaluated. Among the tested compounds, 1-(5-((3-(9H-purin-6-yl)pyridin-2-yl)amino)-2-fluorophenyl)-3-(3-fluorophenyl)urea (7b) and 1-(5-((3-(9H-purin-6-yl)pyridin-2-yl)amino)-2-fluorophenyl)-3-(4-chloro-3-trifluoromethyl)phenyl)urea (7e) are the most potent dual inhibitors against LS513 (GI50 = 0.1 and 0.06 μM, respectively) and VEGFR2 (IC50 = 0.03 and 0.06 μM, respectively). The preclinical study with these compounds are currently underway.

Effect of Swietenia macrophylla seeds on normal and alloxan-induced diabetic rats

Maiti A,,Bhattacharya P,Mandal SC 경희대학교 융합한의과학연구소 2007 Oriental Pharmacy and Experimental Medicine Vol.7 No.4

The methanol extract of the seed of Swietenia macrophylla (Meliaceae) seeds were investigated for its hypoglycaemic activity in normal and alloxan induced diabetic rats. Seed extract suspended in aqueous Tween 80 solution, the graded doses were administered to normal and experimental diabetic rats for 10 days. Fasting blood glucose levels, serum lipid profiles and changes in body weight were evaluated in normal rats while the hepatic marker enzymes and liver glycogen levels were evaluated additionally in diabetic rats. The diabetic groups treated with the seed extract were compared with standard drug glibenclamide. The findings showed the significant antidiabetic potential of the extract in ameliorating the diabetic conditions in diabetic rats. The extract also has hypoglycaemic action in normal rats. A toxicity study has been performed for the extract, which revealed that the extract is safe to use even at the doses of 3.2 mg/kg of body weight orally. The result from the present investigation indicates good correlation between the folk use and scientific investigation.

Binary complexes of tertiary amines with phenylacetylene. Dispersion wins over electrostatics

Maity, Surajit,Patwari, G. Naresh,Karthikeyan, S.,Kim, Kwang S. Royal Society of Chemistry 2010 Physical chemistry chemical physics Vol.12 No.23

<P>The structures of the binary complexes between phenylacetylene and several tertiary amines <I>viz</I>., triethylamine, 1-ethylpiperidine, 1-ethylpiperazine, 1-azabicyclo[2.2.2]octane, and 1,4-diazabicyclo[2.2.2]octane were inferred using infrared-optical double resonance spectroscopy. The IR spectra in the acetylenic C–H stretching region clearly rule out the formation of electrostatic dominated C–H⋯N hydrogen bonded complexes. The IR spectra also point to the fact that all the five tertiary amines interact with the extended π electron density of the phenylacetylene moiety, leading to the formation of multidentate C–H⋯π hydrogen bonded complexes. Additionally a very weak electrostatic C–H⋯N hydrogen bond enhances the stability of the complex marginally. The multidentate C–H⋯π hydrogen bonded complexes are stabilized by a substantial contribution from the dispersion energy.</P> <P>Graphic Abstract</P><P>The fluorescence detected infrared spectra suggest that 1,4-diazabicyclo[2.2.2]octane interacts with phenylacetylene <I>via</I> dispersion dominated multiple C–H⋯π hydrogen bonds. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b918013c'> </P>

Bio-waste onion skin as an innovative nature-driven piezoelectric material with high energy conversion efficiency

Maiti, Sandip,Kumar Karan, Sumanta,Lee, Juhyun,Kumar Mishra, Avnish,Bhusan Khatua, Bhanu,Kon Kim, Jin Elsevier 2017 Nano energy Vol.42 No.-

<P><B>Abstract</B></P> <P>Development of non-toxic, ultra-sensitive, and flexible bio-inspired piezoelectric nanogenerator has become a great challenge for next generation biomedical applications. High performance organic/inorganic materials based piezoelectric nanogenerators suffer from several unavoidable problems such as complex synthesis and high toxicity. Biodegradable and biocompatible piezoelectric material is utmost needed in in-vivo condition to harvest energy for biomedical applications. Here, we report a novel bio-piezoelectric nanogenerator (BPNG) using naturally abundant self-aligned cellulose fibrous untreated onion skin (OS) as efficient piezoelectric material having piezoelectric strength of ∼ 2.8 pC/N. The fabricated OSBPNG generated output voltage, current, instantaneous power density and high piezoelectric energy conversion efficiency of ≈ 18V, ≈ 166nA, ≈ 1.7μW/cm<SUP>2</SUP>, and ≈ 61.7%, respectively, and turn on 30 green LEDs by a single device under repeated compressive stress of ≈ 34kPa and ≈ 3.0Hz frequency. In addition, maximum output voltage (≈ 106V) was achieved when 6 units are connected in series, which instantaneously turns on 73 combined LEDs (30 green, 25 blue, and 18 red). OSBPNG is highly effective during throat movement such as coughing, drinking and swallowing. Furthermore, because it works at very low pressure originating from heart pulse or beat, it could be used in pacemakers and health care units. Finally, OSBPNG successfully differentiates speech signals, indicating its potential for speech recognition.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel homespun approach for bio-piezoelectric nanogenerator (OSBPNG) using onion skin. </LI> <LI> Plant materials are more useful than living creatures in both handling and supply. </LI> <LI> It works at low pressure even from heart pulse, that can be used in health care unit. </LI> <LI> OSBPNG shows output voltage of 18 V with high energy conversion efficiency (61.7%). </LI> <LI> Maximum output voltage (106 V) achieved by assembling 6 units, which turn on 73 LEDs. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Naturally driven bio-waste and biocompatible onion skin base piezoelectric nanogenerator with high output performance (output voltage and area power density of ≈ 18V, and ≈ 1.7μW/cm<SUP>2</SUP>) and high energy conversion efficiency (≈ 61.7%) has been fabricated through simple homespun device fabrication method. More details on the materials and application can be found in the manuscript.</P> <P>[DISPLAY OMISSION]</P>