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SETTING: In alignment with the UN Sustainable Development Goals (SDGs), Kerala State in India aims to end the HIV/AIDS epidemic, using its strong background in local governance to implement the National AIDS Control Programme (NACP). OBJECTIVE: To examine the role of local governments in the implementation of NACP in tune with SDGs. DESIGN: We conducted a state-wide exploratory study using document reviews, key informant and in-depth interviews, which were analysed thematically. RESULTS: Four overarching themes that emerged were 1) preparation for programme implementation, 2) positive impact of local government involvement, 3) convergence with other organisations, and 4) barriers to implementation. Local government commitment to implementing the programme was evidenced by their adoption of the HIV/AIDS policy, facilitative interdepartmental coordination and local innovations. Interventions focused on improving awareness about the disease and treatment, and social, financial and rehabilitative support, which were extended even during the COVID-19 pandemic. Fund shortages and poor visibility of the beneficiaries due to preference for anonymity were challenges to achieving the expected outcomes. CONCLUSION: The NACP is ably supported by local governments in its designated domains of interventions, prevention, treatment, and care and support. The programme can achieve its target to end the AIDS epidemic by overcoming the stigma factor, which still prevents potential beneficiaries from accessing care.

Purpose: The aim of this research is to find out the impact of financial leverage on firm profitability of the listed non-financial firms in Sri Lanka. Design/Methodology/Approach: Total of 290 companies listed on Colombo Stock Exchange (CSE) is considered as the population and the sampling process excluded Banking, Finance, and Insurance companies as they have identical financial characteristics. The study analyzed 82 non-financial firms listed in CSE from year 2013 to 2017. Debt to equity ratio and liquidity were considered as independent variable. Further, sales growth and firm size were considered as control variables. Return on assets of the firm measures the profitability of the firms and incorporated as dependent variable. The study used panel regression analysis, descriptive tests, and correlation analysis. Findings: Fixed effect model reveals that there is a negative significant impact of financial leverage on return on assets of the non-financial firms listed in CSE. The study elaborates a high influence on return on assets due to the independent variables considered in the study since the R2 value becomes 85.43%. Originality: The review of the literature reveals that there are limited number of studies have been carried out incorporating all the non-financial firms in recent past considering the time period of 2013 - 2017. Therefore, this study would provide more insights including the firms’ performance during these periods. Further, it was identified that there are contradictions in the previous findings. Therefore, the study provides more insights to examine the performance of non-financial firms due to the incorporation of debt capital during the period of 2013 – 2017. Theoretical and Policy implications: M&M 1963, agency cost theories are providing the arguments over the mix of debt-to-equity proportion in the organizational capital structure. This study considers the non-financial firm’s performance according to its capital structure. This can be justified that the operational structure of financial and non-financial firms is significantly different. Therefore, the capital structure incorporation would provide significantly different impacts in between financial and non-financial firms. Therefore, the study adds more value by analyzing only the performance of nonfinancial firms based on its financial leverage. Research limitations/ Future research directions: The study uses only the secondary data and the five-year period from 2013 – 2017. Future studies can be done increasing the sample size and employing different methods such as case studies, that would provide more insights to the findings of this study.

In this paper soft pre separations are defined and few of their properties are stated and proved. Also soft pre compactness is defined and properties of a such a space are discussed.

Hypericum perforatum L. commonly known as Saint John’s Wort (SJW) is an economically important medicinal plant known for accumulating its valuable bioactive compounds in a compartmentalized fashion. The dark glands are very rich in hypericin, and translucent glands are filled with hyperforin. The antibiotic properties of the afore mentioned bioactive compounds make it hard to establish tissue regeneration protocols essential to put in place a transformation platform that is required for testing gene function in this challenging species. In this study, we report the establishment of a regeneration and root induction cycle from different types of explants. The regeneration cycle was set up for the continuous supply of roots and leaf explants for downstream transformation experiments. The most effective medium to obtain multiple shoot-buds from node cultures was MS (Murashige and Skoog, Physiol Plant 15:473–497, 1962) medium supplemented with 0.5 mg L−1 6-Benzylaminopurine (BAP) and 0.5 mg L−1 indole-3-butyric acid (IBA). The same combination yielded copious amounts of shoots from root and leaf explants as well. For rooting the elongated shoots, MS medium devoid of plant growth regulators (PGRs) was sufficient. Nevertheless, addition of a low amount of IBA improved the quantity and quality of roots induced. Additionally, the roots obtained on a medium containing IBA readily developed shoot buds.

In transmission frameworks, insulators have a huge impact on the better presentation of the devices. The outside insulators are introduced to an environment that has a high temperature, clamminess similar to pollution from the beachfront and industries. On deposition of contaminants, pollution builds gradually, and spillage current starts to stream on a surface level. Partial Discharge (PD) deteriorates the insulation and leads to the breakdown of the device. The effect of conductive pollution on PD is seen through tests performed on both earthenware and non-ceramic protectors at different pollution levels. To achieve complete information about PD, it is gotten through a PD acknowledgment system that records the PD waveforms close to the regular PD. A couple of sorts of PD signals are difficult to recognize at a starting stage. To crush the test, a Convolutional Neural Network (CNN) based profound learning procedure for PD plan affirmation is presented in this paper. The acquired PD signal is changed into a 3-D (ɸ-q-n) picture. To anticipate such a PD the 3-D (ɸ-q-n) picture is feed as a input to Deep Learning Algorithm. It uses Convolutional Neural Networks (CNN) for picture gathering. In this, Alex Net is used for perceiving the unmistakable PD.

In this paper, we describe Wireless networks have seen unprecedented rise in their size and number of users in recent years. This unprecedented rise is attributed to the rise in the number of mobile computing devices. Moreover the amount of data that is handled by these wireless networks has increased in recent years. One such wireless network that is widely used but is still prone to attacks is WiFi. Wi-Fi protocol (IEEE 802.11), over the years has been upgraded many times, but these upgrades have mainly resulted in increase in the overall data rate of the communication. Little has been done to improve the security of the protocol. This research focuses on inherent flaws in Wired Equivalent Privacy protocol (WEP) used by the 802.11 standard, Temporal Key Integrity Protocol (TKIP) which is considered an interim solution to legacy 802.11 equipment. The demand for ubiquitous personal communications is driving the development of wireless networks that can accommodate mobile voice and data users who move throughout buildings, cities, or countries. The objective of this chapter is to provide the fundamentals of wireless networks so that the general readers can be able to easily grasp some of the ideas in this area.

Hypericum perforatum L. commonly known as Saint John’s Wort (SJW), is an important medicinal plant that has been used for more than 2000 years. Although H. perforatum produces several bioactive compounds, its importance is mainly linked to two molecules highly relevant for the pharmaceutical industry: the prenylated phloroglucinol hyperforin and the naphtodianthrone hypericin. The first functions as a natural antidepressant while the second is regarded as a powerful anticancer drug and as a useful compound for the treatment of Alzheimer’s disease. While the antidepressant activity of SJW extracts motivate a multi-billion dollar industry around the world, the scientific interest centers around the biosynthetic pathways of hyperforin and hypericin and their medical applications. Here, we focus on what is known about these processes and evaluate the possibilities of combining state of the art omics, genome editing, and synthetic biology to unlock applications that would be of great value for the pharmaceutical and medical industries.

The mean and subseasonal monsoon variability is evaluated using simulations from 26 CMIP6 models in the present and future scenarios. In particular, the simulation of the monsoon trough, low pressure systems, and its relationship with seasonal rainfall, teleconnections with Pacific and Atlantic Oceans are analyzed, and the corresponding changes in the future scenario are investigated. Based on the fidelity of the model to simulate mean monsoon features, a set of models with good skill is identified. Selected good models are then used to analyze dynamical and teleconnection features. This study highlights and contrasts the performance of CMIP6 models in simulating various monsoon characteristics with CMIP5 models and further stresses the need for better water management strategies.

With the land-based resources depleting faster, effective exploration and sustained harvesting of the Ocean resources, taking into account the economic growth, social needs and the health of the Oc...

Coronavirus disease 2019 (COVID-19) mortality trends can help discern the pattern of outbreak evolution and systemic responses.This study aimed to explore patterns of COVID-19 deaths in Thiruvananthapuram district from 31 March 2020 to 31 December 2021.Secondary data analysis of COVID-19 deaths in Thiruvananthapuram district was performed.Mortality data were obtained from the district COVID-19 control room, and deaths in the first and second waves of COVID-19 were compared.We summarised data as proportions and medians with the inter-quartile range (IQR) and performed Chi-square tests to make comparisons wherever applicable.As on 31 December 2021, 4587 COVID-19 deaths were reported in Thiruvananthapuram district, with a case fatality rate of 0.91%. We observed high mortality among older persons (66.7%) and men (56.6%). The leading cause of death was bronchopneumonia (60.6%). The majority (88.5%) had co-morbidities, commonly diabetes mellitus (54.9%). The median interval from diagnosis to hospitalisation was 4 days (IQR 2-7), and that from hospitalisation to death was 2 days (IQR 0-6). The deaths reported during the second wave were four times higher than those of the first wave with a higher proportion of deaths in the absence of co-morbidities (p0.001). The majority of the deceased were unvaccinated. Ecological analysis with vaccine coverage data indicated 5.4 times higher mortality among unvaccinated than those who received two vaccine doses.The presence of co-morbidities, an unvaccinated status, and delay in hospitalisation were important reasons for COVID-19 deaths. Primary level health providers can potentially help sustaining vaccination, expeditious referral, and monitoring of COVID-19 patients.

Neurofibromatosis (NF) is a genetic disorder that presents as benign tumours of the nervous system originating from the nerve sheath. It is of three types: Type I, Type II and Schwannomatosis. Type I Neurofibromatosis or von Recklinghausen's disease is the most common type of neurofibromatosis seen and it accounts for 90% of all cases seen. It can be seen as light brown pigmentation spots (Café-au-lait) on the skin and multiple small tumours among the nerves. Oral manifestations of NF are very rare and can be seen as sessile lesion in the tongue or the gingiva. The major complaints of the oral manifestations include difficulty in speech and mastication which it results in progression of periodontal disease. Here, we present a case report of Type I NF which presented as a sessile lesion in the right maxillary gingiva, for which we performed an excisional biopsy using LASER.

With the increase in preventive and restorative dentistry, there is also an increase in the iatrogenic conditions that occur in modern dental practice. The goal of modern dentistry is to provide patients with a holistic solution by providing functional restoration. This case report will highlight one such case where a tooth was diagnosed as having a gingival overgrowth through a perforation during prior endodontic treatment. Proper diagnosis and treatment planning helped restore a tooth that would have been lost.

In the power transformer, the oil-impregnated paper is used for providing insulation between live conducting parts, which comprises of transformer oil and insulating paper (either Kraft paper/Pressboard). These insulating papers are made up of cellulose fibers and it gets easily degraded at higher hot-spot temperature with increase in aging periods. So this affects the lifetime of solid insulation and further transformer life. In this research work, the latest advanced solid insulation named “Nomex paper” made up of aramid polymers is considered as a solid insulating paper material for analyzing the aging behavior. Furthermore, the electrical properties such as breakdown voltage of both oil and paper, flash point and fire point, viscosity have been measured to study the change in characteristics during aging. Also, the level of degradation of solid insulation has been identified by measuring Breakdown voltage of paper under all aging times. On looking standard IEEE C57.91, all these samples were analyzed at the maximum hot-spot temperature of about $130^{\mathbf {\circ }}$C. The results clearly show that the solid insulation gets affected due to deterioration and decomposition.

No abstract provided.

This paper presents a new method for power factor correction with low cost drives. Power factor control is a major role in the improvement of power system stability. Many of the existing systems are expensive and difficult to manufacturer. Nowadays many of the converters have no input power factor correction circuits. The effect of power factor correction circuit is used to eliminate the harmonics present in the system. This type of power factor correction circuit is mostly used in the Switched Reluctance Motor controller drive. Fixed capacitor systems are always leading power factor under at any load conditions. This is unhealthy for installations of power system. The proposed embedded system drive is used to reduce the cost of the equipment and increase the efficiency of the system. Experimental results of the proposed systems are included. It is better choice for effective cost process and energy savings.

The insulator is the major constituents in any electrical transmission and distribution system. Pollution is one of the most significant phenomena, which determine the performance of the insulator and also dissembles the entire electrical power systems. The pollution performance is a diplomatic problem with worldwide, which depend upon the climatic condition. The purpose of high voltage insulator is to withstand electrical stress due to high electric field intensity. A new swing antipollution coating is enforced to improve the flashover voltage. In this work, pollution performance test acquired to the 11kV post type ceramic insulator polluted by the coastal thermal power plant without coating and with Epoxy Resin coating. The experiments have been carried out in both categories (without and with coating) adopt in IEC standard. In simulation modeling, FOV (Flash over voltage) and NSDD (Non-soluble deposit density) are predicted and then compared with computational real value through Artificial neural network in simulation software packages.

In order to improve the reliability of power transmission lines, one of the key issues is to reduce the hazard of contamination flashovers. At the present time, the most efficient way is to clean (or replace) the heavily polluted insulators. This study laboratory based tests were carried out on the model under ac voltage at different pollution levels. A new model based on artificial neural network has been developed to predict flashover from the analysis of leakage current. The input variable to the artificial neural network are mean (Imean), maximum (Imax), and standard deviation (Is) of leakage current extracted along with the input voltage (V) and relative humidity (RH). The target obtained was used to evaluate the performance of the neural network model. The comparison of the simulated and actual (measured) results demonstrates that the ESDD prediction model from the stage characteristics.

The currently available multi-core PCI Express systems running LabVIEW RT (real-time), equipped with FPGA cards for data acquisition and real-time parallel signal processing, greatly shorten the design and implementation cycles of large-scale, real-time data acquisition and control systems. This paper details a data acquisition and real-time tomography system using LabVIEW RT for the bolometer diagnostic on the ASDEX Upgrade tokamak (Max Planck Institute for Plasma Physics, Garching, Germany). The transformation matrix for tomography is pre-computed based on the geometry of distributed radiation sources and sensors. A parallelized iterative algorithm is adapted to solve a constrained linear system for the reconstruction of the radiated power density. Real-time bolometer tomography is performed with LabVIEW RT. Using multi-core machines to execute the parallelized algorithm, a cycle time well below 1 ms is reached.

The twin unidirectional turbine topology was recently proposed with the promise of very significant improvements in the energy capture in Oscillating Water Column (OWC) based wave energy plants. Here, we present the initial results of the experimental validation of the twin unidirectional impulse turbine topology. A scale model of the concept was built and tested using simulated bidirectional flow. The model consists of two 165 mm impulse turbines each individually coupled to 375 W grid connected induction machines. An oscillatory flow test rig was used to simulate bidirectional flow to test the model. The results of the experiments validate the concept of the twin turbine configuration. The proposed topology utilizes no moving parts and achieves more than 50% efficiency over a broad range of flow coefficients. A comparison with other competing turbines (viz, a twin Wells' turbine, a linked guide vane impulse turbine and a fixed guide vane impulse turbine) is done, based on actual measurements in the Indian wave energy plant. The results from the experiments are scaled to evaluate the design features of a 50 GWh wave energy plant. � 2010 Elsevier Ltd.

Experimental results from near shore bottom standing OWC based wave energy plants in Japan and India have now been available for about a decade. Historically the weakest link in the conversion efficiency of OWC based wave energy plants built so far has been the bidirectional turbine. This is possibly because a single turbine has been required to deliver power when the plant is exposed to random incident wave excitation varying by a factor of 10. A new topology that uses twin unidirectional turbines (which features a high efficiency spanning a broad range) is proposed. Using the Indian Wave Energy plant as a case study, it is shown that the power output from such a module considerably exceeds existing optimal configurations including those based on a fixed guide vane impulse turbine, linked guide vane impulse turbine or a Well's turbine. A wave to wire efficiency of the order of 50% over the incident range is shown to be feasible in a credible manner by showing the output at all stages of the conversion process. A frequency domain technique is used to compute the OWC efficiency and a time domain approach used for the power module with the turbine pressure being the pivotal variable. � 2008 Elsevier Ltd. All rights reserved.

One of the best-studied plant defense systems, the glucosinolate-myrosinase system of the Brassicales, is composed of thioglucosides known as glucosinolates and their hydrolytic enzymes, the myrosinases. Tissue disruption brings these components together, and bioactive products are formed as a consequence of myrosinase-catalyzed glucosinolate hydrolysis. Among these products, isothiocyanates have attracted most interest as chemical plant defenses against herbivores and pathogens and health-promoting compounds in the human diet. Previous research has identified specifier proteins whose presence results in the formation of alternative product types, e.g. nitriles, at the expense of isothiocyanates. The biological roles of specifier proteins and alternative breakdown products are poorly understood. Here, we assessed glucosinolate breakdown product profiles obtained upon maceration of roots, seedlings and seeds of Arabidopsis thaliana Columbia-0. We identified simple nitriles as the predominant breakdown products of the major endogenous aliphatic glucosinolates in root, seed, and seedling homogenates. In agreement with this finding, genes encoding nitrile-specifier proteins (NSPs) are expressed in roots, seeds, and seedlings. Analysis of glucosinolate breakdown in mutants with T-DNA insertions in any of the five NSP genes demonstrated, that simple nitrile formation upon tissue disruption depended almost entirely on NSP2 in seeds and mainly on NSP1 in seedlings. In roots, about 70-80 % of the nitrile-forming activity was due to NSP1 and NSP3. Thus, glucosinolate breakdown product profiles are organ-specifically regulated in A. thaliana Col 0, and high proportions of simple nitriles are formed in some parts of the plant. This should be considered in future studies on biological roles of the glucosinolate-myrosinase system.

Transformers are essential components of electric Power Generation, Transmission and Distribution. The Majority of Power Transformers depends on liquid dielectrics as an insulating medium and heat transfer. Transformer oil can be replaced by alternate oils like Coconut oil, Pongamia Pinnata oil, Palm oil due to their biodegradability and environment friendly nature. This Paper deals with the individual effect of Natural Esters. Investigations of various parameters like BDV, Viscosity, Flash and Fire Point are done according to their Standards. From the Experimental analysis, the properties of Palm oil are high compared to others. The average breakdown strength of palm oil is higher than mineral oil. Comparing the experimental result, cost and availability, the palm oil may be the best alternate fluid for Transformer.

This study was carried out to define the extent of allelic variation of 3-hydroxy-3-methylglutaryl-CoA reductase gene (HMGR) in wild Hevea accessions, based on SSR polymorphisms existing at their 3’-untranslated regions (UTRs). Existence of two microsatellite alleles and their repeat compositions was demonstrated earlier in cultivated rubber clones. Both alleles contained perfect poly (AG)n repeats interrupted by a short sequence of 12 nucleotides and allelic variation at this microsatellite locus was the result of repeat length polymorphisms. In wild populations of rubber, nine microsatellite alleles (‘A’ to ‘I’) were identified at the HMGR locus revealing a wide allelic diversity compared to cultivated clones. Out of nine, four alleles (‘B’, ‘C’, ‘D’ and ‘G’) were present in higher frequencies than the others. In total, 15 allelic combinations were noticed for HMGR among wild accessions and four of them were unique. Twenty-five out of 60 wild accessions were found to be homozygous for the above four alleles (‘BB’, ‘CC’, ‘DD’ and ‘GG’) and the rest were heterozygous, characterized by 11 different allelic combinations. Repeat-length polymorphisms were noticed in these four alleles prevailing among wild Hevea accessions. Genetic relatedness of Mato Grosso accessions with cultivated Hevea clones, as revealed through this study, is in agreement with earlier reports on phylogenetic studies using molecular markers. This work is a significant step towards understanding the functional variability of HMGR for latex production in Hevea brasiliensis.

Energy is an important component of development and energy availability determines the quality of life, contributing to basic needs such as providing drinking water as well as lighting. Often effective steps are not taken to minimize the environmental damage caused by a variety of pollutions associated with energy generation from fossil fuels. The world should develop renewable and environmentally friendly energy sources, and at the same time should use energy efficient devices and systems for lighting, drinking water production, etc. The oceans are large resources of renewable energy and drinking water. The countries should invest now in developing suitable designs to tap these enormous resources from oceans. This paper discusses some initiatives taken in this regard in India.

Ocean energy is an important and promising renewable energy for the future. Even though extensive technology development and demonstrations have occurred in the areas of ocean thermal energy, wave energy and tidal energy over the last 40 years, commercial plants based on these technologies are very slow in coming up because of the high capital costs. In recent years, due to increase in the fossil fuel costs, renewable energies such as solar photo voltaic systems and wind energy systems have become cost competitive. Ocean energy systems are likely to become cost competitive in a decade or so, especially for remote islands and coastal areas. This chapter presents the highlights of developments in the areas of ocean thermal energy, wave energy and tidal energy.

Over the past ten decades the power transformers insulation mainly depends on the insulating fluid which is derived from the mineral oil and synthetic oil. But these oils are not environmentally friendly due to their biodegradability behavior. And also the availability of mineral oil will meet its extinction in the future. There are several researches going on in the properties of natural esters which are the probable alternative for the Mineral oil. This work is based on the natural insulating fluid selection for the power transformers insulation by finding their critical properties and checks their properties with the addition of suitable mass function of Nanocomposites. Mustard oil (MO), Rice bran oil (RBO) and Sunflower oil (SFO) is taken as the samples according to their Monounsaturated fatty acid (MUFA) composition for thermal aging process. They are categorized as High level, Medium level and Low level MUFA composition in the oil. This work has been carried out in the laboratory which results as the Mustard oil which is highly monounsaturated in nature shows better performance than the other two oils after thermally heating the oil for 60 hours. By blending the inorganic compounds like silica and zinc oxide Nano particles into the oils there is considerable increment in the breakdown voltage. The silica plays a dominant role in the breakdown voltage increment of the rice bran oil and sunflower oil.

Insulation of transformer has been an integral part of condition assessment for many years. The insulating oil playing the role of dielectric barrier as well as heat escape route especially in power transformer. Primary drawback of mineral oil is that it can present an unacceptable fire risk when it was located near to domestic hats. With silicone fluids, we can meet code requirements for fire protection. We use this reliable and effective insulation for liquid-filled design even when transformer must be located very close to load or near buildings. This dissertation aims in finding the better characteristic performance of insulating fluid for optimized function of power transformers. The effect of characteristic properties of insulation fluid with nano additives was analyzed. The nanofluid model which reduces the potential stress of fluid is shown with comsol software.

Nickel hydrazine nitrate is an energetic coordination compound having explosive properties in between that of primary and secondary. This compound was used to develop a new type of detonator by replacing the sensitive primary explosive, lead azide in conventional detonators and keeping RDX (cyclotrimethylenetrinitramine) as the output secondary explosive. The detonator consists of three regions, viz., initiation, deflagration-to-detonation transition (DDT), and output. The initiation and the electrical rating of 1A/1W no-fire were achieved using a suitable squib. The DDT and the output were taken care of, by pressing requisite quantities of Nickel hydrazine nitrate and RDX, respectively at required densities in a stainless steel stem channel. The detonator assembly involves crimping the squib and the stem channel in a stainless steel housing and applying a suitable resin at the crimped-end for leak tightness. The output was assessed from the dent depth on aluminium plate, volume expansion on lead block, and by achieving veloctiy of detonation of 8200 m/s in mild detonating cords, containing 0.95 g/m of RDX, which indicates full-order detonation. The detonators were tested at system level and found to perform satisfactorily.

Captive broodstock of the spiny lobster, Panulirus homarus, mated successfully and produced more than 105 spawnings over 4 years. Improvements in nutrition and rearing conditions increased the number of spawnings from less than 2, to 4 per year. A single breeder mates three or more times in a year and may spawn more than once following a single mating. An average of four repetitive spawnings per year was recorded. One third of the females spawned 5 times and a single female spawned 7 times in one year. The phyllosoma were released in one or two batches on successive days. The number of phyllosoma larvae released varied from 16 000 to 529 180 with breeder weights ranging from 218 to 696 g.

A pair of subadult Panulirus ornatus was reared in the laboratory from July 2001. The female grew from 0.6 to 1.3 kg and the male from 0.5 to 1.6 kg in 2 years before the first mating in July 2003. In 6 months, from July to December 2003, the pair mated and spawned 3 times, producing 1.6 million eggs and 1.1 million phyllosoma larvae. Mating occurred 25 and 63 days after moulting. The female spawned 2–3 days after mating and the incubation time ranged from 23 to 27 days. The phyllosoma larvae were released over 2 successive days. The growth rate reduced after first mating in both the male and female and the female expended 42% of the total weight gain for egg production.

Plate heat exchangers are often preferred in Ocean Thermal Energy Conversion (OTEC) plants because of the large area they provide for heat transfer leading to higher efficiencies and also because of the compact size of such heat exchangers. Tight control over heat exchanger cleanliness is required as the gap between successive plates is only 3.7 mm and hence fouling can easily impede flow. Based on preliminary evaluation liquid sodium hypochlorite was selected as a possible biocide for fouling control in OTEC operation based on its effectiveness, easy availability, low cost and ease in mid sea replenishment of stock. Subsequently, experiments were conducted in near-shore waters, at residuals of 0.2, 0.5, 0.8, 1.0, 1.2 and 1.5 mg L - 1 in simulated flow chambers (Pederson device) and slime control was achieved at a continuous residual level of 1.2 mg L - 1 . A log reduction 0.8 times in bacterial density between control and chlorinated plates was observed at this regime. Later on experiments were conducted at an OTEC site (65 km offshore off Tuticorin, on the east coast of India) by changing the regime to an intermittent mode, with a view to reducing the amount of chlorine carried on the OTEC barge. These studies showed that an intermittent chlorination regime of 1.2 mg L - 1 residuals, 2 h on/2 h off, was effective for slime control. Since the control of fouling is critical for heat transfer efficiency, the dose and frequency evolved in coastal and oceanic waters using flow chambers was validated using a model plate heat exchanger at the oceanic site onboard a research vessel. In these experiments, a significant log reduction (0.6 times) was observed in bacterial density between control and chlorinated plates in an intermittent mode of 1.2 mg L - 1 once 2 h - 1 for 2 h. In addition, experiments were conducted by varying the frequency of chlorination from 0.5 to 2 h at a dose of 1.2 mg L - 1 to gain a better understanding of biofilm development and the cleanliness efficiencies achievable for plate heat exchangers used for seawater applications.

The Indian wave energy plant is based on the Oscillating Water Column (OWC) principle at Vizhinjam, Kerala and has been a technology demonstration plant. A scheme was envisaged wherein the impulse turbine existing on the caisson is connected to a variable speed alternator to run a desalination plant as load. A methodology has been established to forecast the performance of the turbine, alternator, battery and inverter by means of a simulated wave profile and differential pressure. Actual testing of the scheme was carried out in the laboratory and the scheme was found to be successful. New control logic was introduced, whereby the desalination plant can be run using either the supply from wave power or, during low wave conditions, by electricity board supply or a diesel generator to ensure a continuous supply of fresh water. The scheme for running the reverse osmosis (RO) based desalination plant using wave power has thus been proved and the system has been successfully commissioned.