Target-Sensitive Control of Markov and Semi-Markov Processes

Abhijit Gosavi 제어·로봇·시스템학회 2011 International Journal of Control, Automation, and Vol.9 No.5

We develop the theory for Markov and semi-Markov control using dynamic programming and reinforcement learning in which a form of semi-variance which computes the variability of rewards below a pre-specified target is penalized. The objective is to optimize a function of the rewards and risk where risk is penalized. Penalizing variance, which is popular in the literature, has some drawbacks that can be avoided with semi-variance.

Synthesis of cerium and nickel doped titanium nanofibers for hydrolysis of sodium borohydride

Tamboli, Ashif H.,Gosavi, S.W.,Terashima, Chiaki,Fujishima, Akira,Pawar, Atul A.,Kim, Hern Elsevier 2018 CHEMOSPHERE - Vol.202 No.-

<P><B>Abstract</B></P> <P>A recyclable titanium nanofibers, doped with cerium and nickel doped was successfully synthesized by using sol-gel and electrospinning method for hydrogen generation from alkali free hydrolysis of NaBH<SUB>4</SUB>. The resultant nanocomposite was characterized to find out the structural and physical-chemical properties by a series of analytical techniques such as FT-IR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy-dispersive X-ray spectroscopy),N<SUB>2</SUB> adsorption-desorption and BET (Brunauer–Emmett–Teller), etc. The results revealed that cerium and nickel nanoparticles were homogeneously distributed on the surface of the TiO<SUB>2</SUB> nanofibers due to having similar oxidation state and atomic radium of TiO<SUB>2</SUB>nanofibers with CeO<SUB>2</SUB> and NiO for the effective immobilization of metal ions. The NiO doped catalyst showed superior catalytic performance towards the hydrolysis reaction of NaBH<SUB>4</SUB> at room temperature. These catalysts have ability to produce 305 mL of H<SUB>2</SUB> within the time of 160 min at room temperature. Additionally, reusability test revealed that the catalyst is active even after five runs of hydrolytic reaction, implying the as-prepared NiO doped TiO<SUB>2</SUB> nanofibers could be considered as a potential candidate catalyst for portable hydrogen fuel system such as PEMFC (proton exchange membrane fuel cells).</P> <P><B>Highlights</B></P> <P> <UL> <LI> A recyclable metal doped TiO<SUB>2</SUB> electrospun nanofibers was successfully synthesized. </LI> <LI> Beadles nanofibers and uniform distribution of doped metal facilitate stability to catalyst. </LI> <LI> The metal doped catalyst showed superior activity for hydrolysis of NaBH<SUB>4</SUB>. </LI> <LI> The metal doped TiO<SUB>2</SUB> catalyst could be used repeatedly without significant loss in activity. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Electrically Conductive Photopatternable Silver Paste for High-Frequency Ring Resonator and Band-Pass Filter

Umarji, G.,Qureshi, N.,Gosavi, S.,Mulik, U.,Kulkarni, A.,Kim, T.,Amalnerkar, D. Springer Science + Business Media 2017 Journal of electronic materials Vol.46 No.2

<P>In conventional thick-film technology, there are often problems associated with poor edges, rough surfaces, and reproducibility due to process limitations, especially for high-frequency applications. These difficulties can be circumvented by using thin-film technology, but process cost and complexity remain major concerns. In this context, photopatternable thick-film technology can offer a viable alternative due to its Newtonian rheology, which can facilitate formation of the required sharp edges. We present herein a unique attempt to formulate a photopatternable silver paste with organic (photosensitive polymer) to inorganic (silver and glass) ratio of 30:70, developed in-house by us for fabrication of thick-film-based ring resonator and band-pass filter components. The ring resonator and band-pass component structures were realized by exposing screen-printed film to ultraviolet light at wavelength of 315 nm to 400 nm for 30 s to crosslink the photosensitive polymer. The pattern was subsequently developed using 1% sodium carbonate aqueous solution. For comparison, conventional silver and silver-palladium thick films were produced using in-house formulations. The surface topology and microstructural features were examined by stereomicroscopy and scanning electron microscopy. The smoothness and edge definition of the film were assessed by profilometry. The resistivity of the samples was observed and remained in the range from 3.4 mu a'broken vertical bar cm to 3.6 mu a'broken vertical bar cm. The electrical properties were compared by measuring the insertion loss characteristics. The results revealed that the ring resonator fabricated using the photopatternable silver paste exhibited better high-frequency properties compared with components based on conventional silver or silver-palladium paste, especially in terms of the resonant frequency of 10.1 GHz (versus 10 GHz designed) with bandwidth of 80 MHz. Additionally, the band-pass filter fabricated using the photopatternable silver paste displayed better center frequency (f (0) = 10.588 GHz) and comparable ripple and attenuation bandwidth performance on par with Cu thin film.</P>

Effect of high electronic energy loss of 100MeV gold heavy ions in copper chalcogenides (CuX, X=S, Se) at nanoscale: Opto-electronic properties study

Sharma, R.,Sagade, A.A.,Gosavi, S.R.,Gudage, Y.G.,Ghosh, A.,Kulariya, P.,Sulaniya, I.,Mane, R.S.,Han, S.H. North-Holland 2009 Journal of non-crystalline solids Vol.355 No.31

The copper chalcogenide (CuX, X=S, Se) thin films have been irradiated with 100MeV gold swift heavy ions (SHI) at 10<SUP>11</SUP> and 10<SUP>12</SUP> ions/cm<SUP>2</SUP> fluences. The irradiation effects were probed by characterizing physical properties such as XRD, AFM, optical band gap and electrical resistivity of copper chalcogenide thin films. The increase in irradiation fluence increases the particle size, electrical conductivity and PL intensity of the materials, and the optical band edges were red shifted. The results are explained by quantifying electronic energy loss of ions in both the materials.

Study of microstructure, impedance and dc electrical properties of RuO2-spinel based screen printed ‘green’ NTC thermistor

Shweta Jagtap,Sunit Rane,Rohini Aiyer,Suresh Gosavi,Dinesh Amalnerkar 한국물리학회 2010 Current Applied Physics Vol.10 No.4

The NTC powder materials were prepared chemically using acetates of (Mn–Co–Ni), as precursor materials. The sintering of the powders shows the existence of spinel phases at comparatively low temperature,i.e. 800 ℃. ‘Green’ thick films were prepared by admixing of the spinel powder, RuO2, lead free glass frit and the organic vehicle. Synthesized powders as well as the thermistor films were characterised by FTIR spectroscopy, TG/DTA, XRD and SEM. The electrical parameters like sheet resistance, thermistor constant,temperature co-efficient of resistance of the thick film thermistors are presented. The impedance of the thermistor films was measured and it has been correlated with the theoretical model and its equivalent circuit using the ‘Cole–Cole’ plots.

In situ preparation of a novel organo-inorganic 6,13-pentacenequinone-TiO2 coupled semiconductor nanosystem: a new visible light active photocatalyst for hydrogen generation

Pandit, V.,Arbuj, S.,Hawaldar, R.,Kshirsagar, P.,Mulik, U.,Gosavi, S.,Park, C. J.,Kale, B. Royal Society of Chemistry 2015 Journal of Materials Chemistry A Vol.3 No.8

<P>Previous studies related to the synthesis of stable UV-visible light active photocatalysts for hydrogen generation have been limited to inorganic semiconductors and their nano-and hetero-structures. We demonstrate here the use of an organo-inorganic 6,13-pentacenequinone (PQ)-TiO2 coupled semiconductor nanosystem as an efficient photocatalyst active in visible light for the production of hydrogen. Anatase TiO2 nanoparticles (3-5 nm) were uniformly decorated on thin sheets of monoclinic PQ by an in situ solvothermal method. These as-prepared PQ-TiO2 coupled semiconductor nanosystems had a band gap in the range 2.7-2.8 eV. The strong emission at 590 nm can be attributed to the transfer of electrons from the LUMO energy level of TiO2 to combine with the holes present in the HOMO level of PQ. This electron-hole recombination makes availability of electrons and holes in LUMO of PQ and HOMO of TiO2, respectively. This hybrid semiconductor coupled nanosystem resulted in a rate of hydrogen evolution of 36 456 mu mol h(-1) g(-1) from H2S under UV-visible light; this is four times higher than the rate obtained with TiO2 in earlier reports of UV-visible light active photocatalysts. These results open up a new path to explore inorganic systems coupled with PQ as new photoactive hybrid catalysts in a number of chemical and physicochemical processes.</P>

A comparative study of smica in various body fluids of diagnosed cervical cancer patients and healthy women

( Pooja A. Pachani ),( Rajendra R. Godbole ),( Jeevitaa Kshersagar ),( Rakhi Jagdale ),( Amita Gosavi ),( Somshekhar Patil ),( Rakesh K Sharma ),( Meghnad G. Joshi ) 대한산부인과학회 2022 Obstetrics & Gynecology Science Vol.65 No.1

Objective Cervical cancer (CC) is a major public health problem in women, and its early detection can help reduce morbidity and mortality. The objective of this study was to compare serum levels of soluble major histocompatibility complex class I-related chain A (sMICA) levels in various body fluids between women diagnosed with CC and healthy women. Methods A case-control study was conducted at a tertiary care hospital and a cancer center in Kolhapur, India. Overall, 150 individuals (100 CC patients and 50 healthy women) participated after providing informed written consent. Demographic data, histopathology history, parity, and tumor, node, and metastasis (TNM) staging data were collected. Pap smears, saliva, blood, and urine samples were collected. Pap smears were examined microscopically, and sMICA levels in all samples were determined by enzyme-linked immunoassay (ELISA). Results The mean age of women with cervical cancer was 49.86±8.18 years. Squamous cell carcinoma (70%) was the most common histological variant in CC patients. Serum soluble sMICA levels differed significantly with parity and TNM staging (P<0.05). Mean levels of sMICA were significantly different in samples (CC cases vs. healthy patients; saliva: 166.721±108.718 vs. 0.039±0.005 pg/mL; urine: 82.921±45.580 vs. 0.010±0.005 pg/mL; serum: 35.756±10.799 vs. 0.039±0.005 pg/mL, P<0.001). Conclusion Levels of sMICA in body fluids can be considered as a diagnostic or prognostic tool to determine disease progression or tumor regression.

Nickel-titanium oxide as a novel anode material for rechargeable sodium-ion batteries

Kalubarme, R.,Inamdar, A.,Bhange, D. S.,Im, H.,Gosavi, S.,Park, C. J. Royal Society of Chemistry 2016 Journal of Materials Chemistry A Vol.4 No.44

<P>Nickel-titanium oxide (NiTiO3; NTO) of an ilmenite structure that comprises a layered transition-metal octahedral structure, wherein the zigzag open tunnels are possible routes for Na intercalation, can be a potential anode material for sodium (Na) ion batteries (SIBs). In this study, nanocrystalline NTO particles that are of sizes 3 to 5 nm were prepared using a simple hydrothermal process followed by annealing, and the particles were then tested for SIB applications. The pure-NTO electrode that comprises a hexagonal crystal structure and mesoporous morphology demonstrated a reversible capacity of approximately 521 mA h g(-1) that corresponds to a coulombic efficiency of 67% in the first cycle, which further improved to similar to 98% in the following cycles, at an applied specific current of 50 mA g(-1), and stable cycling performance for 200 cycles. Further, due to the synergetic effect of the porous network structure and high surface area, the NTO electrode exhibited an exceptional rate capability, delivering a capacity of 192 mA h g(-1) at a high specific current of 4000 mA g(-1). The excellent cyclability and rate capability of the NTO electrode are attributed to the improved electronic conductivity and highly porous microstructure of the NTO material, whereby fast charge transfer and facile diffusion of the Na-ions to the active sites are enabled.</P>

Confinement of Ag₃PO₄ nanoparticles supported by surface plasmon resonance of Ag in glass: Efficient nanoscale photocatalyst for solar H₂ production from waste H₂S

Patil, S.S.,Patil, D.R.,Apte, S.K.,Kulkarni, M.V.,Ambekar, J.D.,Park, C.J.,Gosavi, S.W.,Kolekar, S.S.,Kale, B.B. Elsevier 2016 Applied Catalysis B Vol.190 No.-

<P>Ag3PO4 is a good photocatalyst but ubiquitously known for its photocorrosion problem during photocatalytic reaction. Therefore, stabilization of Ag3PO4 with retaining its fundamental properties has immense importance. With this motivation, we designed Ag3PO4 glass nanocomposite to resolve the problem of photocorrosion. Moreover, the effect of size quantization on photocatalytic activity has also been demonstrated by growing the cubic Ag3PO4 nanoparticles with size in the range of 3-9 nm in glass matrix via melt and quenching method. The band gap of Ag3PO4 has been tuned (2.56-2.25 eV) in glass matrix with respect to size. Considering the size tunable band gap of Ag3PO4 glass nanocomposite within visible region, it is demonstrated as a photocatalyst for hydrogen (H-2) production from copious hazardous waste H2S. The utmost H-2 production i.e. 3920.4 mu mol h(-1) g(-1) is obtained using 1 gm of Ag3PO4 glass nanocomposite powder. The apparent quantum yield for H-2 production is calculated to be 5.51% for Ag3PO4 glass nanocomposite. Interestingly, presence of plasmonic Ag was also observed in Ag3PO4 glass nanocomposite which contributes for H-2 production through enhanced light absorption, efficient charge separation and improved stability. Recycling study of sample reveals stable H-2 production efficiency and good stability of the photocatalyst. Surprisingly, catalyst can be reused many times and recovery of catalyst is possible just rinsing with distilled water. All these results demonstrate directly the feasibility of designing a new generation photocatalysts. (C) 2016 Published by Elsevier B.V.</P>

Substrate bias effects during diamond like carbon film deposition by microwave ECR plasma CVD

R.M. Dey,S.B. Singh,A. Biswas,R.B. Tokas,N. Chand,S. Venkateshwaran,D. Bhattacharya,N.K. Sahoo,S.W. Gosavi,S.K. Kulkarni,D.S. Patil 한국물리학회 2008 Current Applied Physics Vol.8 No.1

Diamond like carbon (DLC) coatings were deposited on silicon(11) substrates by microwave electron cyclotron resonance (ECR)plasma CVD process using a plasma of Ar and CH4 gases under the inuence of DC self bias generated on the substrates by applicationof RF (13.56 MHz) power. DLC coatings were deposited under the varying inuence of DC bias (. 60 V to. 150 V) on the Si substrates.atomic force microscopy (AFM), Hardness and elastic modulus determination technique, Raman spectroscopy, scanning electronmicroscopy (SEM) and contact angle measurement. The results indicate that the lm grown at. 100 V bias has optimised propertieslike high sp3/sp2 ratio of carbon bonding, high refractive index (2.262.17) over wide spectral range 4001200 nm, low roughness of0.8 nm, high contact angle (80.) compared to the lms deposited at other bias voltages (. 60 V and . with each other and nd august explanation under the subplantation model for DLC growth.