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.

Reversible fluorescence switching and topochemical conversion in an organic AEE material: polymorphism, defection and nanofabrication mediated fluorescence tuning

Hariharan, P. S.,Moon, D.,Anthony, S. 20151 60 5 2015 Journal of materials chemistry. C, Materials for o Vol.3 No.32

Self-Reversible Mechanochromism and Thermochromism of a Triphenylamine-Based Molecule: Tunable Fluorescence and Nanofabrication Studies

Hariharan, P. S.,Venkataramanan, N. S.,Moon, Dohyun,Anthony, Savarimuthu Philip American Chemical Society 2015 The Journal of Physical Chemistry Part C Vol.119 No.17

<P>A triphenylamine-based fluorophore, 4-((4-methoxyphenyl)(phenyl)amino)benzaldehyde (<B>1</B>), exhibits external-stimuli-responsive self-reversible solid-state fluorescence switching, tunable fluorescence, and a rare phenomenon of temperature-dependent fluorescence. Mechanically grinding a crystalline powder of <B>1</B> converts the blue fluorescence (λ<SUB>max</SUB> = 457 nm) to green (λ<SUB>max</SUB> = 502 nm), but blue fluorescence robustly self-recovers within 8 min. X-ray analysis and theoretical studies suggest that the change from a highly twisted molecular conformation and crystalline form into an amorphous phase with more planar conformation is responsible for the fluorescence switching. Self-reversible fluorescence switching did not show a significant change in fluorescence for several cycles of measurement. Interestingly, <B>1</B> in toluene showed a rare phenomenon of fluorescence enhancement with increasing temperature via activating more vibrational bands that lead to stronger twisted intramolecular charge-transfer (TICT) emissions. Morphological-change-mediated fluorescence tuning has also been demonstrated by fabricating nanoparticles of <B>1</B>. The conversion of highly polydispersed, featureless, different-shaped nanoparticles into nearly uniformly sized spherical nanoparticles (20–25 nm) converts green (λ<SUB>max</SUB> = 502 nm) to blue fluorescence (λ<SUB>max</SUB> = 478 nm). The self-reversible multi-stimuli-responsive fluorescence switching and polymorphism and nanofabrication-mediated fluorescence tuning suggest its potential application in sensors, particularly for fluorescent thermometers.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2015/jpccck.2015.119.issue-17/acs.jpcc.5b00310/production/images/medium/jp-2015-00310a_0012.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp5b00310'>ACS Electronic Supporting Info</A></P>

Dendronic trimaltoside amphiphiles (DTMs) for membrane protein study

Sadaf, Aiman,Du, Yang,Santillan, Claudia,Mortensen, Jonas S.,Molist, Iago,Seven, Alpay B.,Hariharan, Parameswaran,Skiniotis, Georgios,Loland, Claus J.,Kobilka, Brian K.,Guan, Lan,Byrne, Bernadette,Cha Royal Society of Chemistry 2017 Chemical Science Vol.8 No.12

<▼1><P>A novel amphiphile with a dendronic hydrophobic group (DTM-A6) was markedly effective at stabilizing and visualizing a GPCR-G<SUB>s</SUB> complex.</P></▼1><▼2><P>The critical contribution of membrane proteins in normal cellular function makes their detailed structure and functional analysis essential. Detergents, amphipathic agents with the ability to maintain membrane proteins in a soluble state in aqueous solution, have key roles in membrane protein manipulation. Structural and functional stability is a prerequisite for biophysical characterization. However, many conventional detergents are limited in their ability to stabilize membrane proteins, making development of novel detergents for membrane protein manipulation an important research area. The architecture of a detergent hydrophobic group, that directly interacts with the hydrophobic segment of membrane proteins, is a key factor in dictating their efficacy for both membrane protein solubilization and stabilization. In the current study, we developed two sets of maltoside-based detergents with four alkyl chains by introducing dendronic hydrophobic groups connected to a trimaltoside head group, designated dendronic trimaltosides (DTMs). Representative DTMs conferred enhanced stabilization to multiple membrane proteins compared to the benchmark conventional detergent, DDM. One DTM (<I>i.e.</I>, DTM-A6) clearly outperformed DDM in stabilizing human β<SUB>2</SUB> adrenergic receptor (β<SUB>2</SUB>AR) and its complex with G<SUB>s</SUB> protein. A further evaluation of this DTM led to a clear visualization of β<SUB>2</SUB>AR-G<SUB>s</SUB> complex <I>via</I> electron microscopic analysis. Thus, the current study not only provides novel detergent tools useful for membrane protein study, but also suggests that the dendronic architecture has a role in governing detergent efficacy for membrane protein stabilization.</P></▼2>

Implementation of Network Level Security Process through Stepping Stones by Watermarking Methodology

B. Bazeer Ahamed,S. Hariharan 보안공학연구지원센터 2012 International Journal of Future Generation Communi Vol.5 No.4

Comparative investigation on fatigue and moisture absorption behavior of hemp and Jute fibre polymer composites

B. Ravi Kumar,S.S. Hariharan 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.81 No.6

Earth is facing a serious problem of pollution and scarcity of energy sources. The synthetic fibers used in automobile and Aerospace manufacturing sectors are non-renewable and harmful to environment. International Agency such as FAA and SAE is forcing for green fuel, green materials and structures. Further exploration is much needed to understand its potential in structural applications. In the current study, hemp and Jute fibre based composites were developed and tested for assessing their suitability for possible applications in automobile and aerospace sectors. Composites were undergone tensile test, water absorption test, and fatigue analysis to understand its behavior under various loading conditions. The finite element analysis has been carried out to understand the fatigue behaviour of composites. The results revealed that the usage of hemp and jute fibre reinforced composites can improve mechanical properties and have shown a viable alternative to replace synthetic fibres such as glass fibres for specific applications. Hemp reinforced bio-composites have shown better performance as compared to Jute reinforced bio-composites while water resistance characteristics for hemp is poorer to jute fibres.

Experimental and microstructural evaluation on mechanical properties of sisal fibre reinforced bio-composites

B. Ravi Kumar,S.S. Hariharan 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.33 No.2

The natural fibre composites are termed as bio-composites. They have shown a promising replacement to the current carbon/glass fibre reinforced composites as environmental friendly materials in specific applications. Natural fibre reinforced composites are potential materials for various engineering applications in automobile, railways, building and Aerospace industry. The natural fibre selected to fabricate the composite material is plant-based fibre e.g., sisal fibre. Sisal fibre is a suitable reinforcement for use in composites on account of its low density, high specific strength, and high hardness. Epoxy is a thermosetting polymer which is used as a resin in natural fibre reinforced composites. Hand lay-up technique was used to fabricate the composites by reinforcing sisal fibres into the epoxy matrix. Composites were prepared with the unidirectional alignment of sisal fibres. Test specimens with different fibre orientations were prepared. The fabricated composites were tested for mechanical properties. Impact test, tensile test, flexural test, hardness test, compression test, and thermal test of composites had been conducted to assess its suitability in industrial applications. Scanning electron microscopy (SEM) test revealed the microstructural information of the fractured surface of composites.

Experimental investigation on thermal behavior, sound absorption, and flammability of natural fibre polymer composites

Ravi Kumar B.,Hariharan S.S. 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.5

Exhausting oil resources and increasing pollution around the world are forcing researchers to look for new, renewable, biodegradable materials to lead sustainable development. The use of fiber reinforced composites based on natural fibres has increasingly begun as prospective materials for various engineering applications in the automotive, rail, construction and aerospace industries. The natural fiber chosen to make the composite material is plant-based fibre, e.g. jute fibre, and hemp fibre. Thermosetting polymer based Epoxy (LY556) was utilized as matrix material and The composites were produced using hand lay-up technique. The fabricated composites were tested for acoustic testing, thermo-gravimetric analysis (TGA) and flammability testing to asses sound absorption, thermal decomposition and fire resistivity of the structures. Hemp fibre composites have shown improved thermal stability over Jute fibre composites. However, the fire resistance characteristics of jute fibre composites are better as compared to hemp fibre composites. The sound absorption coefficient of composites was found to enhance with the increase of frequency.

A class of rigid linker-bearing glucosides for membrane protein structural study

Sadaf, A.,Mortensen, J.,Capaldi, S.,Tikhonova, E.,Hariharan, P.,Ribeiro, O.,Loland, C.,Guan, L.,Byrne, B.,Chae, P. THE ROYAL SOCIETY OF CHEMISTRY 2016 Chemical Science Vol.7 No.3

<P>Membrane proteins are amphipathic bio-macromolecules incompatible with the polar environments of aqueous media. Conventional detergents encapsulate the hydrophobic surfaces of membrane proteins allowing them to exist in aqueous solution. Membrane proteins stabilized by detergent micelles are used for structural and functional analysis. Despite the availability of a large number of detergents, only a few agents are sufficiently effective at maintaining the integrity of membrane proteins to allow successful crystallization. In the present study, we describe a novel class of synthetic amphiphiles with a branched tail group and a triglucoside head group. These head and tail groups were connected via an amide or ether linkage by using a tris(hydroxylmethyl) aminomethane (TRIS) or neopentyl glycol (NPG) linker to produce TRIS-derived triglucosides (TDTs) and NPG-derived triglucosides (NDTs), respectively. Members of this class conferred enhanced stability on target membrane proteins compared to conventional detergents. Because of straightforward synthesis of the novel agents and their favourable effects on a range of membrane proteins, these agents should be of wide applicability to membrane protein science.</P>

Conformationally Preorganized Diastereomeric Norbornane-Based Maltosides for Membrane Protein Study: Implications of Detergent Kink for Micellar Properties

Das, Manabendra,Du, Yang,Ribeiro, Orquidea,Hariharan, Parameswaran,Mortensen, Jonas S.,Patra, Dhabaleswar,Skiniotis, Georgios,Loland, Claus J.,Guan, Lan,Kobilka, Brian K.,Byrne, Bernadette,Chae, Pil S American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.8

<P>Detergents are essential tools for functional and structural studies of membrane proteins. However, conventional detergents are limited in their scope and utility, particularly for eukaryotic membrane proteins. Thus, there are major efforts to develop new amphipathic agents with enhanced properties. Here, a novel class of diastereomeric agents with a preorganized conformation, designated norbornane-based maltosides (NBMs), were prepared and evaluated for their ability to solubilize and stabilize membrane proteins. Representative NBMs displayed enhanced behaviors compared to n-dodecyl-beta-D-maltoside (DDM) for all membrane proteins tested. Efficacy of the individual NBMs varied depending on the overall detergent shape and alkyl chain length. Specifically, NBMs with no kink in the lipophilic region conferred greater stability to the proteins than NBMs with a kink. In addition, long alkyl chain NBMs were generally better at stabilizing membrane proteins than short alkyl chain agents. Furthermore, use of one well-behaving NBM enabled us to attain a marked stabilization and clear visualization of a challenging membrane protein complex using electron microscopy. Thus, this study not only describes novel maltoside detergents with enhanced protein stabilizing properties but also suggests that overall detergent geometry has an important role in determining membrane protein stability. Notably, this is the first systematic study on the effect of detergent kinking on micellar properties and associated membrane protein stability.</P>