Abstract: | Multi-component reactions are effective in building complex molecules in a single step in a minimum amount of time and with facile isolation procedures; they have high economy1–7 and thus have become a powerful synthetic strategy in recent years.8–10 The multicomponent protocols are even more attractive when carried out in aqueous medium. Water offers several benefits, including control over exothermicity, and the isolation of products can be carried out by single phase separation technique. Pyranopyrazoles are a biologically important class of heterocyclic compounds and in particular dihydropyrano[2,3-c]pyrazoles play an essential role in promoting biological activity and represent an interesting template in medicinal chemistry. Heterocyclic compounds bearing the 4-H pyran unit have received much attention in recent years as they constitute important precursors for promising drugs.11–13 Pyrano[2,3-c]pyrazoles exhibit analgesic,14 anti-cancer,15 anti-microbial and anti-inflammatory16 activity. Furthermore dihydropyrano[2,3-c]pyrazoles show molluscidal activity17,18 and are used in a screening kit for Chk 1 kinase inhibitor activity.19,20 They also find applications as pharmaceutical ingredients and bio-degradable agrochemicals.21–29 Junek and Aigner30 first reported the synthesis of pyrano[2,3-c]pyrazole derivatives from 3-methyl-1-phenylpyrazolin-5-one and tetracyanoethylene in the presence of triethylamine. Subsequently, a number of synthetic approaches such as the use of triethylamine,31 piperazine,32 piperidine,33 N-methylmorpholine in ethanol,34 microwave irradiation,35,36 solvent-free conditions,37–39 cyclodextrins (CDs),40 different bases in water,41 γ -alumina,42 and l-proline43 have been reported for the synthesis of 6-amino-4-alkyl/aryl-3-methyl- 2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles. Recently, tetraethylammonium bromide (TEABr) has emerged as mild, water-tolerant, eco-friendly and inexpensive catalyst. To the best of our knowledge, quaternary ammonium salts, more specifically TEABr, have notbeen used as catalysts for the synthesis of pyrano[2,3-c]pyrazoles, and we decided to investigate the application of TEABr as a catalyst for the synthesis of a series of pyrazole-fused pyran derivatives via multi-component reactions |
Description: | Organic Preparations and Procedures International, 45:429–436, 2013 |
URI: | http://dyuthi.cusat.ac.in/purl/4146 |
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An Efficient Mu ... razole-5-carbonitriles.pdf | (136.6Kb) |
Abstract: | While channel coding is a standard method of improving a system’s energy efficiency in digital communications, its practice does not extend to high-speed links. Increasing demands in network speeds are placing a large burden on the energy efficiency of high-speed links and render the benefit of channel coding for these systems a timely subject. The low error rates of interest and the presence of residual intersymbol interference (ISI) caused by hardware constraints impede the analysis and simulation of coded high-speed links. Focusing on the residual ISI and combined noise as the dominant error mechanisms, this paper analyses error correlation through concepts of error region, channel signature, and correlation distance. This framework provides a deeper insight into joint error behaviours in high-speed links, extends the range of statistical simulation for coded high-speed links, and provides a case against the use of biased Monte Carlo methods in this setting |
Description: | International Journal of Enhanced Research in Science Technology & Engineering, Vol. 2 Issue 12, December-2013, pp: (115-124) |
URI: | http://dyuthi.cusat.ac.in/purl/4184 |
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An efficient sc ... on Monte Carlo Method.pdf | (734.6Kb) |
Abstract: | Semantic Web: Software agents on the Semantic Web may use commonly agreed service language, which enables co-ordination between agents and proactive delivery of learning materials in the context of actual problems. The vision is that each user has his own personalized agent that communicates with other agents. |
URI: | http://dyuthi.cusat.ac.in/purl/4172 |
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eLearning and Semantic Web.pdf | (802.6Kb) |
Abstract: | Clustering combined with multihop communication is a promising solution to cope with the energy requirements of large scale Wireless Sensor Networks. In this work, a new cluster based routing protocol referred to as Energy Aware Cluster-based Multihop (EACM) Routing Protocol is introduced, with multihop communication between cluster heads for transmitting messages to the base station and direct communication within clusters. We propose EACM with both static and dynamic clustering. The network is partitioned into near optimal load balanced clusters by using a voting technique, which ensures that the suitability of a node to become a cluster head is determined by all its neighbors. Results show that the new protocol performs better than LEACH on network lifetime and energy dissipation |
Description: | International Journal of Information Processing, 4(3), 9-16, 2010 |
URI: | http://dyuthi.cusat.ac.in/purl/4167 |
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Energy Aware Cl ... ol for Sensor Networks.pdf | (537.3Kb) |
Abstract: | This paper underlines a methodology for translating text from English into the Dravidian language, Malayalam using statistical models. By using a monolingual Malayalam corpus and a bilingual English/Malayalam corpus in the training phase, the machine automatically generates Malayalam translations of English sentences. This paper also discusses a technique to improve the alignment model by incorporating the parts of speech information into the bilingual corpus. Removing the insignificant alignments from the sentence pairs by this approach has ensured better training results. Pre-processing techniques like suffix separation from the Malayalam corpus and stop word elimination from the bilingual corpus also proved to be effective in training. Various handcrafted rules designed for the suffix separation process which can be used as a guideline in implementing suffix separation in Malayalam language are also presented in this paper. The structural difference between the English Malayalam pair is resolved in the decoder by applying the order conversion rules. Experiments conducted on a sample corpus have generated reasonably good Malayalam translations and the results are verified with F measure, BLEU and WER evaluation metrics |
Description: | Proceedings of the 1st Amrita ACM-W Celebration on Women in Computing in India |
URI: | http://dyuthi.cusat.ac.in/purl/4139 |
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English to Mala ... A Statistical Approach.pdf | (646.6Kb) |
Abstract: | Sensor networks are one of the fastest growing areas in broadwireless ad hoc networking (?Eld. A sensor node, typically'contains signal-processing circuits, micro-controllers and awireless transmitter/receiver antenna. Energy saving is oneof the critical issue for sensor networks since most sensorsare equipped with non-rechargeable batteries that have limited lifetime.In thiswork, four routing protocols for wireless sensor networks vizFlooding, Gossiping, GBR and LEACH have been simulated using Tiny OS and their power consumption is studied usingcaorwreiredTOoSuStIuMs.ingAMirceaal2izMaotitoens.of these protocols has been carried out using mica 2 motes |
URI: | http://dyuthi.cusat.ac.in/purl/4178 |
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Evaluation of t ... reless Sensor Networks.pdf | (906.9Kb) |
Abstract: | Sensor networks are one of the fastest growing areas in broad of a packet is in transit at any one time. In GBR, each node in the network can look at itsneighbors wireless ad hoc networking (? Eld. A sensor node, typically'hop count (depth) and use this to decide which node to forward contains signal-processing circuits, micro-controllers and a the packet on to. If the nodes' power level drops below a wireless transmitter/receiver antenna. Energy saving is one certain level it will increase the depth to discourage trafiE of the critical issue forfor sensor networks since most sensors are equipped with non-rechargeable batteries that have limited lifetime. |
Description: | Ad Hoc and Ubiquitous Computing, 2006. ISAUHC'06. International Symposium on |
URI: | http://dyuthi.cusat.ac.in/purl/4145 |
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Evaluation of the Power Consumption of.pdf | (906.1Kb) |
Abstract: | In Statistical Machine Translation from English to Malayalam, an unseen English sentence is translated into its equivalent Malayalam sentence using statistical models. A parallel corpus of English-Malayalam is used in the training phase. Word to word alignments has to be set among the sentence pairs of the source and target language before subjecting them for training. This paper deals with certain techniques which can be adopted for improving the alignment model of SMT. Methods to incorporate the parts of speech information into the bilingual corpus has resulted in eliminating many of the insignificant alignments. Also identifying the name entities and cognates present in the sentence pairs has proved to be advantageous while setting up the alignments. Presence of Malayalam words with predictable translations has also contributed in reducing the insignificant alignments. Moreover, reduction of the unwanted alignments has brought in better training results. Experiments conducted on a sample corpus have generated reasonably good Malayalam translations and the results are verified with F measure, BLEU and WER evaluation metrics. |
Description: | 2012 International Conference on Advances in Computing and Communications |
URI: | http://dyuthi.cusat.ac.in/purl/4160 |
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Extension schem ... cal Machine Translator.pdf | (219.2Kb) |
Abstract: | n this paper we address the problem of face detection and recognition of grey scale frontal view images. We propose a face recognition system based on probabilistic neural networks (PNN) architecture. The system is implemented using voronoi/ delaunay tessellations and template matching. Images are segmented successfully into homogeneous regions by virtue of voronoi diagram properties. Face verification is achieved using matching scores computed by correlating edge gradients of reference images. The advantage of classification using PNN models is its short training time. The correlation based template matching guarantees good classification results. |
URI: | http://dyuthi.cusat.ac.in/purl/4183 |
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Face Recognitio ... listic Neural Networks.pdf | (218.8Kb) |
Abstract: | In this paper we address the problem of face detection and recognition of grey scale frontal view images. We propose a face recognition system based on probabilistic neural networks (PNN) architecture. The system is implemented using voronoi/ delaunay tessellations and template matching. Images are segmented successfully into homogeneous regions by virtue of voronoi diagram properties. Face verification is achieved using matching scores computed by correlating edge gradients of reference images. The advantage of classification using PNN models is its short training time. The correlation based template matching guarantees good classification results |
Description: | Nature & Biologically Inspired Computing, 2009. NaBIC 2009. World Congress on |
URI: | http://dyuthi.cusat.ac.in/purl/4142 |
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Face Recognitio ... listic Neural Networks.pdf | (216.3Kb) |
Abstract: | A series of novel naphthyridine derivatives 3 and 4 was prepared from substituted pyridine 2 and ketones using ZnCl2 as catalyst under microwave irradiation conditions. All the compounds were evaluated for AChE inhibitory activity and promising compounds 3d, 3e, 4b, and 4g was identified. Representative compounds 3d and 3e were found to show insignificant THLE-2 liver cell viability/toxicity. The binding mode between X-ray crystal structure of human AChE and compounds was studied using molecular docking method and fitness scores were found to be in good correlation with the activity data. |
Description: | Med Chem Res (2012) 21:1785–1795 DOI 10.1007/s00044-011-9695-0 |
URI: | http://dyuthi.cusat.ac.in/purl/4162 |
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A facile and si ... ivity, and molecular m.pdf | (1.024Mb) |
Abstract: | A simple and facile strategy for the synthesis of highly substituted imidazoles has been developed by multi-component condensation of 1,2-diketone, aldehyde, amine, and ammonium acetate in presence of tetrabutyl ammonium bromide as catalyst |
Description: | Res Chem Intermed (2012) 38:359–365 DOI 10.1007/s11164-011-0352-5 |
URI: | http://dyuthi.cusat.ac.in/purl/4137 |
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A facile strate ... iumbromide as catalyst.pdf | (308.6Kb) |
Abstract: | A methodology for translating text from English into the Dravidian language, Malayalam using statistical models is discussed in this paper. The translator utilizes a monolingual Malayalam corpus and a bilingual English/Malayalam corpus in the training phase and generates automatically the Malayalam translation of an unseen English sentence. Various techniques to improve the alignment model by incorporating the morphological inputs into the bilingual corpus are discussed. Removing the insignificant alignments from the sentence pairs by this approach has ensured better training results. Pre-processing techniques like suffix separation from the Malayalam corpus and stop word elimination from the bilingual corpus also proved to be effective in producing better alignments. Difficulties in translation process that arise due to the structural difference between the English Malayalam pair is resolved in the decoding phase by applying the order conversion rules. The handcrafted rules designed for the suffix separation process which can be used as a guideline in implementing suffix separation in Malayalam language are also presented in this paper. Experiments conducted on a sample corpus have generated reasonably good Malayalam translations and the results are verified with F measure, BLEU and WER evaluation metrics |
Description: | Procedia Technology 00 (2011) 000–000,2nd International Conference on Communication, Computing & Security |
URI: | http://dyuthi.cusat.ac.in/purl/4150 |
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A framework for ... ing statistical models.pdf | (592.6Kb) |
Abstract: | In this paper we describe the methodology and the structural design of a system that translates English into Malayalam using statistical models. A monolingual Malayalam corpus and a bilingual English/Malayalam corpus are the main resource in building this Statistical Machine Translator. Training strategy adopted has been enhanced by PoS tagging which helps to get rid of the insignificant alignments. Moreover, incorporating units like suffix separator and the stop word eliminator has proven to be effective in bringing about better training results. In the decoder, order conversion rules are applied to reduce the structural difference between the language pair. The quality of statistical outcome of the decoder is further improved by applying mending rules. Experiments conducted on a sample corpus have generated reasonably good Malayalam translations and the results are verified with F measure, BLEU and WER evaluation metrics |
Description: | Proceedings of Fourth International Conference on Information Processing, Bangalore, India |
URI: | http://dyuthi.cusat.ac.in/purl/4138 |
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A Framework of ... m English to Malayalam.pdf | (363.2Kb) |
Abstract: | Free/Open Source Software (FOSS) concept is very important in the academic community. The open philosophy of FOSS is consistent with academic freedom and the open dissemination of knowledge and information in academia. FOSS can lower the barriers to access of ICTs by reducing the cost of the software. This article discusses the success story of CUSAT's adoption of Free/Open Source Software |
Description: | National Conference on Free Software |
URI: | http://dyuthi.cusat.ac.in/purl/4166 |
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FreeOpen Source ... CUSAT A Success Story.pdf | (202.2Kb) |
Abstract: | In this paper, we have evolved a generic software architecture for a domain specific distributed embedded system. The system under consideration belongs to the Command, Control and Communication systems domain. The systems in such domain have very long operational lifetime. The quality attributes of these systems are equally important as the functional requirements. The main guiding principle followed in this paper for evolving the software architecture has been functional independence of the modules. The quality attributes considered most important for the system are maintainability and modifiability. Architectural styles best suited for the functionally independent modules are proposed with focus on these quality attributes. The software architecture for the system is envisioned as a collection of architecture styles of the functionally independent modules identified |
Description: | 2007 international conference on software emgineering theory and practice(SETP-07) |
URI: | http://dyuthi.cusat.ac.in/purl/4177 |
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A Generic Softw ... ibuted Embedded System.pdf | (473.8Kb) |
Abstract: | Statistical Machine Translation (SMT) is one of the potential applications in the field of Natural Language Processing. The translation process in SMT is carried out by acquiring translation rules automatically from the parallel corpora. However, for many language pairs (e.g. Malayalam- English), they are available only in very limited quantities. Therefore, for these language pairs a huge portion of phrases encountered at run-time will be unknown. This paper focuses on methods for handling such out-of-vocabulary (OOV) words in Malayalam that cannot be translated to English using conventional phrase-based statistical machine translation systems. The OOV words in the source sentence are pre-processed to obtain the root word and its suffix. Different inflected forms of the OOV root are generated and a match is looked up for the word variants in the phrase translation table of the translation model. A Vocabulary filter is used to choose the best among the translations of these word variants by finding the unigram count. A match for the OOV suffix is also looked up in the phrase entries and the target translations are filtered out. Structuring of the filtered phrases is done and SMT translation model is extended by adding OOV with its new phrase translations. By the results of the manual evaluation done it is observed that amount of OOV words in the input has been reduced considerably |
URI: | http://dyuthi.cusat.ac.in/purl/4157 |
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Handling OOV Wo ... nslation for Malayalam.pdf | (261.3Kb) |
Abstract: | Page 1. Dr. G Santhosh Kumar Cochin University Page 2. Who wants to be successful in life? Page 3. What can we do to become more successful? Page 4. Hare and Tortoise retold Page 5. What can we do to become more successful? Page 6. What can we do to become more successful? A good leader will lead quietly and subtly, from the rear, without fuss, without fanfare Page 7. What can we do to become more successful? Life is always moving – either we are moving forward, growing, or - we are moving back, dying Don't fear failure |
URI: | http://dyuthi.cusat.ac.in/purl/4153 |
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How to become successful.pdf | (5.634Mb) |
Abstract: | The role of the supervisor• agree a timetable of meetings at the start of your project and stick to it;• make sure that each meeting has a focus eg “setting a research problem”,“analysing the data”;• send something that can form the basis of a discussion about your progress to your supervisor before each meeting. This could include your research plan, early results of your data collection or draft chapters;• turn up on time to each meeting you have arranged. Do not assume that your supervisor is available at all times to see you;• at the end of each |
URI: | http://dyuthi.cusat.ac.in/purl/4154 |
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How to do a dissertation.pdf | (1.214Mb) |
Abstract: | Page 1. ICT Tools for Teaching & Learning G Santhosh Kumar Cochin University Page 2. Agenda • What is ICT? • Why integrate ICT in Education? • What are the Challenges? • What are the good resources? Page 3. Questions # “Despite the increasing use of ICT, the need for teachers is as great as ever” # “Placing ICT in schools will automatically improve the quality of education that children receive” #”The Internet is unsafe for children to use because there is so much dangerous material available on it” Page 4. What is ICT? • ICT is short for .. |
URI: | http://dyuthi.cusat.ac.in/purl/4168 |
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ICT Tools for Teaching &.pdf | (1.077Mb) |
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