543 research outputs found
Report of Acoustic Test on PSLV IS.1/2L Structure
The results of acoustic conducted on PSLV IS.1/2L at Acoustic Test Facility are briefly given. It contains test set up,
Instrumentation details and tables of spectral response
Development and characterization of silicone/phosphorus modified epoxy materials and their application as anticorrosion and antifouling coatings
Epoxy resin is chosen for our present study owing to its exceptional combination of properties such as easy processing, high safety, excellent solvent and chemical resistance, toughness, low shrinkage on cure, good electrical, mechanical and corrosion resistance with excellent adhesion to many substrates. This versatility in formulation made epoxy resins widely applied for surface coatings, adhesives, laminates, composites, potting, painting materials, encapsulant for semiconductor and insulating material for electric devices. There are numerous paint/coating systems based
on epoxy resin available for corrosion and fouling prevention. They however are not completely satisfactory in field applications, where high corrosion, fouling and flame resistance are required. The demand for epoxy resin as corrosion/fouling resistant coatings is restricted mainly due to
its inferior characteristics like poor impact strength, high rigidity, and moisture absorbing nature besides inadequate flame retardant properties. It is for this reason that silicones and phosphorus-based compounds are used as modifier in this work by intercrosslinking network mechanism (ICN) to obtain epoxy resin with desired properties ideally suitable for field applications for preventing corrosion and fouling with flame retardantancy.
The present work involves the development of solvent free silicone/phosphorus modified epoxy coating systems, since solvent free coating systems are widely used for numerous applications due to their lower cost per unit film thickness, freedom from fire and pollution hazard and ability to provide better performance. For the development of coating systems, epoxy resin (X) serves as base material, hydroxyl terminated dimethylsiloxane (HTPDMS) as modifier, aminopropyltriethoxysilane (APS) as crosslinking agent and dibutyltindilaurate (DBTDL) as catalyst. Polyamidoamine (A), aromatic amine adducts (B) and phosphorus-containing diamine (C) were used as curing agents. The study also describes the evaluation of corrosion resistant behaviour of unmodified epoxy and siliconized epoxy coatings by potentiodynamic polarization
method, electrochemical impedance spectroscopy (EIS), salt-spray and antifouling tests. The results are discussed.CSIR.
National Metallurgical Laboratory.
Madras Centre.
Fundação para a Ciência e Tecnologia
Anti-tumor and anti-angiogenic activity of novel hydantoin derivatives: Inhibition of VEGF secretion in liver metastatic osteosarcoma cells
A series of new azaspiro bicyclic hydantoin derivatives has been designed and synthesized. Initially, the anti-proliferative effect of the hydantoin derivatives was evaluated against human ovarian cancer cells (SKOV-3 and OVSAHO) and murine osteosarcoma cells (LM8 and LM8G7). Among the tested compounds, 8-(3-fluorobenzyl)-1′-(4-(methylsulfonyl)benzyl)-8-azaspiro[bicyclo[3.2.1]octane-3,4′-imidazolidine]-2′,5′-dione (7h) and 8-(3,4-difluorobenzyl)-1′-(4-(methylsulfonyl)benzyl)-8-azaspiro[bicyclo[3.2.1]octane-3,4′-imidazolidine]-2′,5′-dione (7i) showed a significant anti-proliferative activity against the OVSAHO and LM8G7 cells. The real-time monitoring of the effect of the compounds 7h and 7i against the proliferation of LM8G7 was revealed that resulting IC50 values were 102 μM and 13 μM, respectively. We reasoned that the presence of fluorine atom at the 3rd position of the phenyl ring of the hydantoin side chain may determine the potency of the molecule. Furthermore, the compound 7i inhibited the tube formation of the mouse endothelial cells. Finally, the treatment of the compound 7i against the proliferation of LM8G7 cells demonstrated the down regulation of the secretion of VEGF, indicate the potential angioinhibitory effects. In conclusion, our findings demonstrate the suppression of the secretion of VEGF by LM8G7 cells by the compound 7i might contribute at least in part to the antitumor action
Matrix Ranking- An important PRA tool to assess farmers preferences and priorities
Matrix ranking is an important PRA tool to assess and study the preferences of farmers for a particular technology over
others, with respect to crop or animal based technologies. The preferences and criteria for the same are also studied in the
process. The following study gives a first-hand idea of farmers’ relative preferences for different varieties of rice, mustard,
tomato, chilli, garden pea, fish and lac hosts. The results of the matrix ranking for different varieties of rice revealed that,
the variety “Arize 6444” was the most preferred one followed by “Abhishek”. “Pusa Mahak” was the leading variety of
mustard followed by Pusa Bold. Swarna Sampada is more preferred tomato variety among the farmers. Among fish,
“Rohu” was widely preferred by the respondents due to its higher yield, more market demand, resistance to water quality
and higher market price
PRA Techniques in Agriculture: Common Diagraming and Mapping Tools
PRA techniques and tools commands paramount importance in bottom up approach of planning and implementation of agricultural programmes. The following paper describes the various PRA techniques used in the study such as Transect, Mobility map, Timeline and Time trend. Apart from PRA, other methods of data collection such as use of semi-structured interview schedule, direct observation and focus group methods were also used to elicit information from the villagers
TRACE ELEMENT ANALYSIS OF GROUNDWATER FROM RASIPURAM TALUK, TAMILNADU, INDIA
Groundwater is an important source of water for many municipalities, industries and for irrigation, which needs careful and critical assessment of its quality. The groundwater samples collected from Rasipuram Taluk, Which is located in southern part of India, have been used for the trace element analysis. The main reason behind this analysis is based on the fact that, the industrial wastewater contributes to the groundwater pollution. The samples were analyzed for trace elements such as cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), manganese (Mn) and zinc (Zn) using Atomic Absorption Spectrometer (AAS) and other associated equipments. It was found that the concentrations of trace elements in groundwater of the study area are well within the prescribed limit
Secure Message Dissemination with QoS Guaranteed Routing in Internet of Vehicles
Internet of Vehicles (IoV) is a variant of vehicular adhoc network (VANET) where vehicles can communicate with other vehicles, infrastructure devices, parking lots and even pedestrians. Communication to other entities is facilitates through various services like DSRC, C2C-CC. Fake messages can be propagated by attackers for various selfish needs. Complex authentication procedures can affect the propagation of emergency messages. Thus a light weight mechanism to ensure the trust of messages without affecting the delivery deadlines for emergency messages. Addressing this problem, this work proposes a clustering based network topology for IoV where routing is optimized for message dissemination of various classes using hybrid meta-heuristics. In addition, two stage message authentication technique combining collaborative authentication with Bayesian filtering is proposed to verify the authenticity of message. Through simulation analysis, the proposed solution is found to detect fake messages with an accuracy of 96% with 10% lower processing delay compared to existing works
BIG DATA CHARACTERISTICS, CLASSIFICATION AND CHALLENGES - A REVIEW
The data is an assest of great importance for any organization. Big data is the large collection of data; it includes different types of data collected from banking, e-commerce, insurance, manufacturing, social media and business data etc . Big data Analytics is the examine the bulk amount of data. To deal the large amount of data traditional techniques are inefficient, less accuracy and less performance. Big data technologies are face the large and complex data in efficient manner. Hadoop technology is designed to process the Big data. Hadoop is an open source software used for distributed processing of big data among the servers. Parallelism technique is used to process the large amount of data. Currently the big data analytics is the one of the research area and development. Nowadays the big data has great importance and good choice for new researchers. The paper's main purpose is to discuss the features of big data and the technological challenges
Multi-modal multi-class Parkinson disease classification using CNN and decision level fusion
Parkinson disease is the second most common neurodegenerative disorder, as
reported by the World Health Organization. In this paper, we propose a direct
three-Class PD classification using two different modalities, namely, MRI and
DTI. The three classes used for classification are PD, Scans Without Evidence
of Dopamine Deficit and Healthy Control. We use white matter and gray matter
from the MRI and fractional anisotropy and mean diffusivity from the DTI to
achieve our goal. We train four separate CNNs on the above four types of data.
At the decision level, the outputs of the four CNN models are fused with an
optimal weighted average fusion technique. We achieve an accuracy of 95.53
percentage for the direct three class classification of PD, HC and SWEDD on the
publicly available PPMI database. Extensive comparisons including a series of
ablation studies clearly demonstrate the effectiveness of our proposed
solution.Comment: 10th International Conference on Pattern Recognition and Machine
Intelligence (Acepted
Evaluation of Energy Consumption using Receiver–Centric MAC Protocol in Wireless Sensor Networks
At present day’s wireless sensor networks, obtain a lot consideration to researchers. Maximum number of sensor nodes are scattered that can communicate with all others. Reliable data communication and energy consumption are the mainly significant parameters that are required in wireless sensor networks. Many of MAC protocols have been planned to improve the efficiency more by enhancing the throughput and energy consumption. The majority of the presented medium access control protocols to only make available, reliable data delivery or energy efficiency does not offer together at the same time. In this research work the author proposes a novel approach based on Receiver Centric-MAC is implemented using NS2 simulator. Here, the author focuses on the following parametric measures like - energy consumption, reliability and bandwidth. RC-MAC provides high bandwidth without decreasing energy efficiency. The results show that 0.12% of less energy consumption, reliability improved by 20.86% and bandwidth increased by 27.32% of RC-MAC compared with MAC IEEE 802.11
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