Development & evaluation of different acoustic models for Malayalam continuous speech recognition

Performance of any continuous speech recognition system is dependent on the accuracy of its acoustic model. Hence, preparation of a robust and accurate acoustic model lead to satisfactory recognition performance for a speech recognizer. In acoustic modeling of phonetic unit, context information is of prime importance as the phonemes are found to vary according to the place of occurrence in a word. In this paper we compare and evaluate the effect of context dependent tied (CD tied) models, context dependent (CD) and context independent (CI) models in the perspective of continuous speech recognition of Malayalam language. The database for the speech recognition system has utterance from 21 speakers including 11 female and 10 males. Our evaluation results show that CD tied models outperforms CI models over 21%.

Queueing Models with Vacations and Working Vacations

The thesis entitled “Queueing Models with Vacations and Working Vacations" consists of seven chapters including the introductory chapter. In chapters 2 to 7 we analyze different queueing models highlighting the role played by vacations and working vacations. The duration of vacation is exponentially distributed in all these models and multiple vacation policy is followed.In chapter 2 we discuss an M/M/2 queueing system with heterogeneous servers, one of which is always available while the other goes on vacation in the absence of customers waiting for service. Conditional stochastic decomposition of queue length is derived. An illustrative example is provided to study the effect of the input parameters on the system performance measures. Chapter 3 considers a similar setup as chapter 2. The model is analyzed in essentially the same way as in chapter 2 and a numerical example is provided to bring out the qualitative nature of the model. The MAP is a tractable class of point process which is in general nonrenewal. In spite of its versatility it is highly tractable as well. Phase type distributions are ideally suited for applying matrix analytic methods. In all the remaining chapters we assume the arrival process to be MAP and service process to be phase type. In chapter 4 we consider a MAP/PH/1 queue with working vacations. At a departure epoch, the server finding the system empty, takes a vacation. A customer arriving during a vacation will be served but at a lower rate.Chapter 5 discusses a MAP/PH/1 retrial queueing system with working vacations.In chapter 6 the setup of the model is similar to that of chapter 5. The signicant dierence in this model is that there is a nite buer for arrivals.Chapter 7 considers an MMAP(2)/PH/1 queueing model with a nite retrial group

Thermal Properties of Polytetrafluoroethylene/ Sr2Ce2Ti5O16 Polymer/Ceramic Composites

Polytetrafluoroethylene (PTFE) composites filled with Sr2Ce2Ti5O16 ceramic were prepared by a powder processing technique. The structures and microstructures of the composites were investigated by X-ray diffraction and scanning electron microscopy techniques. Differential scanning calorimetry showed that the ceramic filler had no effect on the melting point of the PTFE. The effect of the Sr2Ce2Ti5O16 ceramic content [0–0.6 volume fraction (vf)] on the thermal conductivity, coefficient of thermal expansion (CTE), specific heat capacity, and thermal diffusivity were investigated. As the vf of the Sr2Ce2Ti5O16 ceramic increased, the thermal conductivity of the specimen increased, and the CTE decreased. The thermal conductivity and thermal expansion of the PTFE/Sr2Ce2Ti5O16 composites were improved to 1.7 W m21 8C21 and 34 ppm/8C, respectively for 0.6 vf of the ceramics. The experimental thermal conductivity and CTE were compared with different theoretical models.

Impact of Node Mobility on Routing Protocols for Wireless Sensor Networks

Wireless sensor networks monitor their surrounding environment for the occurrence of some anticipated phenomenon. Most of the research related to sensor networks considers the static deployment of sensor nodes. Mobility of sensor node can be considered as an extra dimension of complexity, which poses interesting and challenging problems. Node mobility is a very important aspect in the design of effective routing algorithm for mobile wireless networks. In this work we intent to present the impact of different mobility models on the performance of the wireless sensor networks. Routing characteristics of various routing protocols for ad-hoc network were studied considering different mobility models. Performance metrics such as end-to-end delay, throughput and routing load were considered and their variations in the case of mobility models like Freeway, RPGM were studied. This work will be useful to figure out the characteristics of routing protocols depending on the mobility patterns of sensors

International Initiatives for Regulating Access to Genetic Resources

In light of the various international instruments and international agencies that are actively engaged in resolving the issue of ABS, the present work tries to find an answer to the larger question how far the above agencies have succeeded in regulating access and make sure of benefit sharing. In this process, the work comprehensively analyses the work of different agencies involved in the process. It tries to find out the major obstacles that stand in the way of fulfilment of the benefit sharing objective and proposes the ways and means to tackle them. The study first traces the legal foundations of the concept of property in GRs and associated TK.For this, it starts with analysis of the nature of property and the questions related to ownership in GRs as contained in the CBD as well as in various State legislations. It further examines the notion of property before and after the enactment of the CBD and establishes that the CBD contains strong private property jurisprudence.Based on the theoretical foundation of private property right,Chapter 3 analyses the benefit sharing mechanism of the CBD, i.e. the Nagoya Protocol. It searches for a theoretical convergence of the notion of property as reflected in the two instruments and successfully establishes the same. It makes an appraisal of the Nagoya regime to find out how far it has gone beyond the CBD in ensuring the task of benefit sharing and the impediments in its way.Realizing that the ITPGRFA forms part of the CBD system, Chapter 4 analyses the benefit sharing structure of ITPGRFA as revealed through its multilateral system. This gives the work the benefit of comparing two different benefit sharing models operating on the same philosophy of property. This chapter tries to find out whether there is conceptual coherence in the notion of property when the benefit sharing model changes. It alsocompares the merits and demerits of both the systems and tries to locate the hurdles in achieving benefit sharing. Aware of the legal impediments caused by IPRs in the process of ABS, Chapter 5 tries to explore the linkages between IPRs and GRs and associated TK and assesses why contract-based CBD system fails before the monopoly rights under TRIPS. Chapter 6 analyses the different solutions suggested by the international community at the TRIPS Council as well as the WIPO (World Intellectual property Organisation) and examines their effectiveness. Chapter 7 concludes that considering the inability of the present IP system to understand the grass root realities of the indigenous communities as well as the varying situations of the country of origin, the best possible way to recognise the CBD goals in the TRIPS could be better achieved through linking the two instruments by means of the triple disclosure requirement in Article 29 as suggested by the Disclosure Group during the TRIPS Council deliberations. It also recommends that considering the nature of property in GR, a new section/chapter in the TRIPS dealing with GRs would be another workable solution.