Acquisition, Processing and Image Generation System for Camera Data Onboard Spacecraft

C.V.R Subbaraya Sastry,G.S Narayan Rao,N Ramakrishna,V.K Hariharan International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.3

The primary goal of any communication spacecraft is to provide communication in variety of frequency bands based on mission requirements within the Indian mainland. Some of the spacecrafts operating in S-band utilizes a 6m or larger aperture Unfurlable Antenna (UFA for S-band links and provides coverage through five or more S-band spot beams over Indian mainland area. The Unfurlable antenna is larger than the satellite and so the antenna is stowed during launch. Upon reaching the orbit, the antenna is deployed using motors. The deployment status of any deployment mechanism will be monitored and verified by the telemetered values of micro-switch position before the start of deployment, during the deployment and after the completion of the total mechanism. In addition to these micro switches, a camera onboard will be used for capturing still images during primary and secondary deployments of UFA. The proposed checkout system is realized for validating the performance of the onboard camera as part of Integrated Spacecraft Testing (IST) conducted during payload checkout operations. It is designed for acquiring the payload data of onboard camera in real-time, followed by archiving, processing and generation of images in near real-time. This paper presents the architecture, design and implementation features of the acquisition, processing and Image generation system for Camera onboard spacecraft. Subsequently this system can be deployed in missions wherever similar requirement is envisaged.

Effect of annealing on the physical properties of thermally evaporated In2S3 thin films

S. Rasool,K. Saritha,K.T. Ramakrishna Reddy,M.S. Tivanov,A.V. Trofimova,S.E. Tikoto,L. Bychto,A. Patryn,M. Maliński,V.F. Gremenok 한국물리학회 2019 Current Applied Physics Vol.19 No.2

The structural, compositional, morphological and optical properties of In2S3 thin films, prepared by thermal evaporation technique and annealed in sulfur ambient at different temperatures have been investigated. The grazing incident X-ray diffraction patterns have indicated polycrystalline form and predominantly cubic structure of annealed In2S3 films. The scanning electron microscopy revealed textured surface with uniformly distributed grains and the grain size increased with increase of annealing temperature. The optical parameters of the films have been determined using conventional transmission and reflection spectra as well as from surface photovoltage measurements.

Somatic Mutations in TSC1 and TSC2 Cause Focal Cortical Dysplasia

Lim, J.S.,Gopalappa, R.,Kim, S.H.,Ramakrishna, S.,Lee, M.,Kim, W.i.,Kim, J.,Park, S.M.,Lee, J.,Oh, J.H.,Kim, H.D.,Park, C.H.,Lee, J.S.,Kim, S.,Kim, D.S.,Han, J.M.,Kang, H.C.,Kim, H.(.,Lee, J.H. University of Chicago Press [etc.] 2017 American journal of human genetics Vol.100 No.3

<P>Focal cortical dysplasia (FCD) is a major cause of the sporadic form of intractable focal epilepsies that require surgical treatment. It has recently been reported that brain somatic mutations in MTOR account for 15%-25% of FCD type II (FCDII), characterized by cortical dyslamination and dysmorphic neurons. However, the genetic etiologies of FCDII-affected individuals who lack the MTOR mutation remain unclear. Here, we performed deep hybrid capture and amplicon sequencing (read depth of 100 x-20,012 x) of five important mTOR pathway genes-PIK3CA, PIK3R2, AKT3, TSC1, and TSC2-by using paired brain and saliva samples from 40 FCDII individuals negative for MTOR mutations. We found that 5 of 40 individuals (12.5%) had brain somatic mutations in TSC1 (c.64C>T [p.Arg22Trp] and c.610C>T [p.Arg204Cys]) and TSC2 (c.4639G>A [p.Va11547I1e]), and these results were reproducible on two different sequencing platforms. All identified mutations induced hyperactivation of the mTOR pathway by disrupting the formation or function of the TSC1TSC2 complex. Furthermore, in utero CRISPR-Cas9-mediated genome editing of Tsc1 or Tsc2 induced the development of spontaneous behavioral seizures, as well as cytomegalic neurons and cortical dyslamination. These results show that brain somatic mutations in TSC1 and TSC2 cause FCD and that in utero application of the CRISPR-Cas9 system is useful for generating neurodevelopmental disease models of somatic mutations in the brain.</P>

Design and stress analysis of femur bone implant with composite plates

Ramakrishna, S.,Pavani, B. Techno-Press 2020 Biomaterials and Biomechanics in Bioengineering Vol.5 No.1

Development of lightweight implant plates are important to reduce the stress shielding effect for a prosthesis of femur bone fractures. Stainless steel (SS-316L) is a widely used material for making implants. Stress shielding effect and other issues arise due to the difference in mechanical properties of stainless steel when compared with bone. To overcome these issues, composite materials seem to be a better alternative solution. The comparison is made between two biocompatible composite materials, namely Ti-hydroxyapatite and Ti-polypropylene. "Titanium (Ti)" is fiber material while "hydroxyapatite" and "polypropylene" are matrix materials. These two composites have Young's modulus closer to the bone than stainless steel. Besides the variety of bones, present paper constrained to femur bone analysis only. Being heaviest and longest, the femur is the most likely to fail among all bone failures in human. Modelling of the femur bone, screws, implant and assembly was carried out using CATIA and static analysis was carried out using ANSYS. The femur bone assembly was analyzed for forces during daily activities. Ti-hydroxyapatite and Ti-polypropylene composite implants induced more stress in composite implant plate, results less stress induced in bone leading to a reduction in shielding effect than stainless steel implant plate thus ensuring safety and quick healing for the patient.

Evaluation of Relative Fluoride Toxicity and Its Impact on Growth, Economic Characters and Fecundity of the Silkworm, Bombyx mori L.

( S. Ramakrishna ),( B. Surendra Nath ),( Jayaprakash ) 한국잠사학회 2007 International Journal of Industrial Entomology Vol.8 No.2

A detailed evaluation of relative toxicity of fluoride to the 5th instar larvae of PM and NB4D2 races of silkworm and the effects of lethal, sublethal and prevailing levels of fluoride in groundwater on the growth, economic characters and fecundity of the silkworm, Bombyx mori (Lepidoptera: Bombycidae) were studied. The feeding of mulberry, Morus alba leaves treated with lethal and sublethal doses of fluoride to PM and NB4D2 races of silkworms from the beginning of the 5th instar to the end of the feeding period resulted in significant reduction in growth, single cocoon weight, single shell weight, silk index, average filament length, and fecundity when compared to controls. These changes were more pronounced on exposure to lethal dose than sublethal dose and in general, the changes induced by fluoride were more striking in NB4D2 than PM, indicating the greater resistance of PM to higher fluoride levels. Groundwater quality in sericulturally important villages of Karnataka and Andhra Pradesh States has been studied with special reference to the presence of fluoride. On exposure to dose of prevailing levels in the waters of sericulturally important areas, die changes observed on growth, economic characters and fecundity were slightly lower when compared to controls and the decrease was found to be insignificant (P≥0.05). It was concluded that, though minute dose (4.0 ppm) of fluoride did not have any toxic impact, it is toxic at higher concentrations to silkworms.

Evaluation of Relative Fluoride Toxicity and Its Impact on Growth, Economic Characters and Fecundity of the Silkworm, Bombyx mori L.

S. Ramakrishna,B. Surendra Nath,Jayaprakash 한국잠사학회 2004 International Journal of Industrial Entomology Vol.8 No.2

A detailed evaluation of relative toxicity of fluoride to the 5th instar larvae of PM and NB4D2 races of silkworm and the effects of lethal, sublethal and prevailing levels of fluoride in groundwater on the growth, economic characters and fecundity of the silkworm, Bombyx mori (Lepidoptera: Bombycidae) were studied. The feeding of mulberry, Morus alba leaves treated with lethal and sublethal doses of fluoride to PM and NB4D2 races of silkworms from the beginning of the 5th instar to the end of the feeding period resulted in significant reduction in growth, single cocoon weight, single shell weight, silk index, average filament length, and fecundity when compared to controls. These changes were more pronounced on exposure to lethal dose than sublethal dose and in general, the changes induced by fluoride were more striking in NB4D2 than PM, indicating the greater resistance of PM to higher fluoride levels. Groundwater quality in sericulturally important villages of Karnataka and Andhra Pradesh States has been studied with special reference to the presence of fluoride. On exposure to dose of prevailing levels in the waters of sericulturally important areas, the changes observed on growth, economic characters and fecundity were slightly lower when compared to controls and the decrease was found to be insignificant (P ³ 0.05). It was concluded that, though minute dose (4.0 ppm) of fluoride did not have any toxic impact, it is toxic at higher concentrations to silkworms.

Lys-63-specific Deubiquitination of SDS3 by USP17 Regulates HDAC Activity

Ramakrishna, S.,Suresh, B.,Lee, E.-J.,Lee, H.-J.,Ahn, W.-S.,Baek, K.-H. The American Society for Biochemistry and Molecula 2011 The Journal of biological chemistry Vol.286 No.12

Shifts in Protein Metabolism in Hemolymph and Fat Body of the Silkworm, Bombyx mori L. in Response to Fluoride Toxicity

Ramakrishna, S.,Jayaprakash, Jayaprakash Korean Society of Sericultural Science 2007 International Journal of Industrial Entomology Vol.15 No.1

Changes in protein metabolism were studied in hemolymph and fat body on days 1, 3, 5 and 7 of the fifth-instar silkworm, Bombyx mori, exposed to lethal, sublethal doses and prevailing levels of fluoride in groundwater in Karnataka and Andhra Pradesh States of India. The total protein content indicated a depletion followed by a concomitant increase in accumulation of free amino acids. Concurrently, the activity of protease in both of the tissues was also increased. A steady enhancement in the activities of alanine aminotransferase and aspartate aminotransferase paralleled the elevation of glutamate dehydrogenase activity in the tissues studied. It is presumed, on the basis of these results, that the fluoride toxicity causes major changes in protein metabolism of the silkworms.

Shifts in Protein Metabolism in Hemolymph and Fat Body of the Silkworm, Bombyx mori L. in Response to Fluoride Toxicity

S. Ramakrishna,Jayaprakash 한국잠사학회 2007 International Journal of Industrial Entomology Vol.15 No.1

Solution for a semi-infinite plate with radial crack and radial crack emanating from circular hole under bi-axial loading by body force method

Manjunath, B.S.,Ramakrishna, D.S. Techno-Press 2009 Interaction and multiscale mechanics Vol.2 No.2

Machine or structural members subjected to fatigue loading will have a crack initiated during early part of their life. Therefore analysis of members with cracks and other discontinuities is very important. Finite element method has enjoyed widespread use in engineering, but it is not convenient for crack problems as the region very close to crack tip is to be discretized with very fine mesh. However, as the body force method (BFM), requires only the boundary of the discontinuity (crack or hole) to be discretized it is easy versatile technique to analyze such problems. In the present work fundamental solution for concentrated load x + iy acting in the semi-infinite plate at an arbitrary point $z_0=x_0+iy_0$ is considered. These fundamental solutions are in complex form ${\phi}(z)$ and ${\psi}(z)$ (England 1971). These potentials are known as Melan potentials (Ramakrishna 1994). A crack in the semi-infinite plate as shown in Fig. 1 is considered. This crack is divided into number of divisions. By applying pair of body forces on a division, the resultant forces on the remaining 'N'divisions are to be found for which ${\phi}_1(z)$ and ${\psi}_1(z)$ are derived. Body force method is applied to calculate stress intensity factor for crack in semi-infinite plate. Also for the case of crack emanating from circular hole in semi-infinite plate radial stress, hoop stress and shear stress are calculated around the hole and crack. Convergent results are obtained by body force method. These results are compared with FEM results.