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New Delhi Thursday, 8 February, 2018 - 11:00

Spirit of inquiry and curiosity are traditions in India,  country that has a history of nurturing science, said Hon’ble President Shri Ram Nath Kovind at a seminar organised as a part of the second edition of Nobel Prize Series, India, at the Rashtrapati Bhavan here.

The Nobel Prize Series India 2018, under the theme ‘Science Impacts Life’, concluded at the Rashtrapati Bhavan after day-long deliberations with academicians, bureaucrats, industrialists and four Nobel Laureates expressing their views on diverse issues from science communication to quality faculty, and in general, focusing on what ails the education system in the country.

The Nobel Laureates, Prof. Richard J. Roberts (Physiology or Medicine), Prof. Serge Haroche (Physics), Prof. Christiane Nusslein-Volhard (Physiology or Medicine) and Prof. Tomas Lindahl (Chemistry), said that India had great potential, but needed to spend more on education and science. They opined that the percentage of GDP invested on science was far too low and needed to go up if India, with a talented pool of students, wanted to produce quality research.

The Hon'ble President graced ‘Ek Pradarshini 2018 - The Best of Indian Science’ exhibits at the Rashtrapati Bhavan. The exhibition was curated by the Department of Biotechnology as part of the Nobel Prize Series - India 2018.

Organised jointly by the Nobel Media AB, Sweden and the Department of Biotechnology, Ministry of Science and Technology, the Nobel Prize Series India builds upon the ongoing discourse on the need for restructuring science education and research in India. The Nobel Prize Series aims to spread knowledge about the science for which the Nobel Prize were awarded and shares the inspirational stories of the Nobel Laureates with global audience. The 2018 Series started in Goa on February 1.

Inaugurating the national seminar on ‘Science Impacts Life’, President Kovind said that in the 70 years since independence, belief in science has shaped the Indian society. “From agriculture to harnessing the energy of the atom, from vaccine innovation to advances in space technology, science has helped us build our nation – brick by brick or molecule by molecule”, he said. He also added that while it takes great skill to lead a technically capable research team of 15 or 20 people, it takes greater skill to communicate with such a team of qualified scientists. It takes related, but different capacities, to lead an institution of a few thousands. And it takes great patience for our learned scientists to explain the intricacies of science and technology to ordinary people. And yet, our scientists have to do this for the benefit of society. By communicating science, you will further the cause of science, he said.

The event was also attended by the Hon’ble Minister of Science and Technology, Earth Sciences, Environment, Forest and Climate Change, Dr. Harsh Vardhan said that science not only impacts life, but can solve problems. There was a need for scientists to go beyond achieving personal glory and think how their research can solve unresolved problems. Speaking on the occasion, Hon’ble Minister for HRD, Shri Prakash Javadekar said science has brought about huge change in our lives.

Speaking on the occasion, Nobel Laureate Prof. Serge Haroche said it was a challenge to bring as many people to higher education as possible. “We need trained teachers to train teachers”, he said. Pointing out that the investment on science is low in India, he added that it is important that teachers are paid on par with other jobs in the country.

Prof. Juleen R. Zierath, member of the Nobel Committee, emphasized that breakthroughs came from people being challenged, and stressed the importance of infrastructure for science.  Putting man on the moon meant raising the bar on interest in Science, she said, adding that we need to celebrate grassroot scientific heroes and communicate science better.

Nobel Laureate Prof. Richard Roberts said the ability to communicate science to people was important and that scientists should learn how to communicate effectively. “Want more Indian Nobel Laureates? Give them opportunities”, he said.

Emphasising the role of teachers in shaping the next generation of Nobel Laureates, Prof. Tomas Lindahl recollected, “I couldn’t have achieved the Nobel Prize without a good teacher.” There is strong interrelationships between education and research, and that relationship should be strengthened, he said

India's population, pollution, healthcare, food security and biodiversity face challenges that can find solutions in science, Nobel Laureate Prof. Christiane Nüsslein-Volhard said. She praised enthusiasm and talent of Indian students and said that the science here is of great quality, but struggled to thrive due to other challenges India faces. There was a need of measures to improve the environment ---provide cleaner environment to bring talented people back to India, she said.

The day-long event saw two panel discussions on building world-class institutes in India and helping science reach our society. The panel discussions were graced by head of institutes, the Nobel Laureates, philanthropists, and educationalists. At the concluding session, the two panels submitted their recommendations to the Hon’ble President.

Videos of the event:

Inaugural address: Facebook Live video
Panel Discussion 1: Facebook Live video
Panel Discussion 2: Facebook Live video
Concluding session: Facebook Live video - Nobel Prize Series India, Facebook Live video - Office of the President

Disclosure: The team behind Research Matters promoted by Gubbi Labs was responsible for content that went on the exhibits of Ek Pradarshini - The Best of Indian Science.

Section: General, Science, Society, Policy, News, Events Source:
Bengaluru Wednesday, 7 February, 2018 - 09:00

A group of researchers from Anna University, Chennai and University of Madras, Chennai have studied the influence of seawater intrusion on groundwater in the coastal aquifers of Kalpakkam in Tamil Nadu.

Seawater intrusion or the movement of seawater into the freshwater aquifer zone increases groundwater salinity, posing a huge environmental impact in coastal regions globally. Sea level rise and decrease in groundwater levels due to overexploitation can result in seawater intrusion; affecting major ions and nutrients in groundwater.

To understand the effects of such intrusion, researchers collected 33 groundwater samples from open and bore wells in the study area during post-monsoon and pre-monsoon seasons. The study area, covering 455 square kilometres, is surrounded by the Bay of Bengal in the east, the saline Edaiyur backwaters in the north, and Buckingham Canal in the west. These samples were then analysed for physico-chemical parameters such as major ions and stable isotopes.

Sodium (Na+) was found to be the dominant cation or positive ion, and chloride (Cl) the dominant anion or negative ion during both seasons. Electrical conductivity (EC), Na+, and Clvalues were high in groundwater from wells near salt pans, Buckingham Canal, and the backwater regions, indicating salinization and seawater intrusion.

Around 45% of the groundwater samples showed presence of Na+ and Cl  ions, due to salinization; while around 21% had traces of other ions (Ca2+-Mg2+-Cl), indicating silicate weathering-- where silicate rocks undergo weathering and the dust mixes with the water, and reverse ion exchange processes.

The results showed a strong positive correlation of Cl with EC and other ions, indicating seawater intrusion and mixing of saline backwater with freshwater.  Tests also suggest other effects, like influence of fertilizers and other anthropogenic activities, also affecting the quality of the groundwater.  The seawater mixing index (SMI), based on four major ions (Na+, Mg2+, Cl, and SO42−) was used to quantify seawater mixing with groundwater aquifers.  The SMI values strongly suggest groundwater chemistry being controlled by saline water mixing.

Groundwater quality was calculated by comparing EC, Na+, Cl, SMI, and stable isotope values with BIS (Bureau of Indian Standards) and WHO (World Health Organization) permissible limits.

The study reveals that about 201 square kilometres of the study area was found to be affected by salinization, with the groundwater classified as unsuitable for drinking.

“To overcome this situation, it is necessary to change the pumping pattern from shoreline to inland through construction of new well fields and the creation of freshwater ridges by rainfall recharge methods, which effectively control sea water intrusion and recovery of groundwater quality” suggest the researchers as one of the solutions to the intrusion.

Section: General, Science, Ecology, News Source: Link
Bengaluru Tuesday, 6 February, 2018 - 08:40

An international team, including scientists from California Institute of Technology, USA, University of Oxford, UK, Indian Institute of Technology Bombay, Mumbai, Tata Institute of Fundamental Research, Pune and several other universities from around the globe, are probing radio waves emanating from the source that the produced gravitational wave event GW170817. Their study could reveal more information about the events that cause gravitational waves and its aftermath.

On August 17, 2017, cosmologists around the globe were elated as LIGO and Virgo detectors had detected yet another gravitational wave on the outskirts of the galaxy NGC 4993 at a distance of 40 megaparsecs from Earth (1 parsec is around 3.26 light years), later named GW170817. This time, however,the situation was different from previous detections. Gravitational waves detected earlier were said to be produced due to the merger of two black holes, which weren’t expected to produce electromagnetic signals, like X rays and radio waves. GW170817, on the other hand, was produced when two neutron stars spiralled into each other, producing not just gravitational waves, but also other electromagnetic radiations from the aftermath of the merger. This means one could actually ‘see’ the event that caused the gravitational waves. Because of this, GW170817 has been hailed as a significant  breakthrough in multi-messenger astronomy.

Global Relay of Observatories Watching Transients Happen (GROWTH), an international scientific collaborative project studying the physics of fast changing events in the cosmos, like supernovae, neutron star and black hole mergers, and near-earth asteroids, observed the neutron star merger that caused GW170817 at different wavelengths, from radio waves to x-rays. Their observations have revealed the merger generating a hot explosion known as kilonova, radio wave emissions as the hot explosion slammed into surrounding gas, and optical and infrared waves from a cocoon of material expanding at close to the speed of light from the aftermath of the merger.

In the new study, the scientists observed radio waves emanating from the location of the merger, 16 days after the detection of GW170817. They believe the radio waves may be a result of either, a collimated jet of particles travelling close to the speed of light, viewed slightly off-axis from our line of sight, or from a slowly expanding cocoon of materials spewed out from the merger.   

A further analysis of the radio waves within 100 days from the merger would, according to the researchers, enable scientist to measure the angular velocity and geometry of the debris from the merger, allowing them to distinguish between the two models.

The detection of the counterpart radio source, according to the authors, “allows us to diagnose the energetics and environment of the merger”, and thus forms a window into the spectacular events that caused GW170817 and the aftermath of that merger.

Section: General, Science, News Source:
Goa Friday, 2 February, 2018 - 16:51

Scientists from Centre for Glaciology, Wadia Institute of Himalayan Geology, Dehradun, Wilfrid Laurier University, Waterloo, Canada, Chhattisgarh Council of Science and Technology, Raipur and  National Centre for Antarctic and Ocean Research, Goa studying the surge-type glaciers in Karakoram have noticed irregular behaviour among some of the glaciers in Karakoram. They have now carried out a comprehensive study to try and answer some of the anomalies.

Glaciers are persistent bodies of dense ice, forming the largest reservoir of fresh water on Earth. Mostly confined to the polar regions of our planet, pockets of glaciers are also found in the Andes, Rocky Mountains, parts of East Africa, and more locally in the Himalayas. Glaciers, much like other bodies of fresh water, flow, but at an incredibly slow pace compared to their liquid counterparts, sometimes moving only around 3 feet per day.

Surging is phenomenon where a glacier flows at a much higher pace, compared to normal and can persist for a few month or even several years. Glaciers exhibiting periodic surges are usually referred to as surge-type glaciers. The Karakoram mountain range spanning India, China and Pakistan is home to the highest concentration of surge-type glaciers. The glaciers here are known for irregular ice movement with little or no synchrony to neighboring, similar ice masses. Although surging has been attributed to internal conditions of the individual glaciers, the reasons for these irregularities and anomalies as well the exact cause for the surges are yet to be understood.

In their study, the scientists from NCAOR conducting a comprehensive mapping of the surge-type glaciers and the impact due to surges based on satellite imagery (Landsat and ASTER), ground observations and archival material since 1840s. The study identified 221 surge-type glaciers in the region covering a total of 43% of the glaciers in the Karakoram region.

The scientists studied different factors and parameters of the surge-type glaciers. According to the authors of the paper “ Surge intervals are identified for 27 glaciers with two or more surges, including 9 not previously reported. Mini-surges and kinematic waves are documented and surface diagnostic features indicative of surging”.

Apart from these the study also found that surge-cycle timing, intervals and mass transfers are unique to each glacier, with the climate playing no role in influencing these parameters.

“Our study increases known numbers and diversity of surge events, and surge-related features. It includes some 100 surge-type glaciers not previously reported, and refines current knowledge of their distribution and movement characteristics” remark the researchers about the study. With the data from this study, the phenomenon of surging can be better understood.

Update (8 Feb 2018):  “National Centre for Antarctic and Ocean Research (NCAOR), Goa” was changed to “Centre for Glaciology, Wadia Institute of Himalayan Geology, Dehradun, Wilfrid Laurier University, Waterloo, Canada, Chhattisgarh Council of Science and Technology, Raipur and  National Centre for Antarctic and Ocean Research, Goa” as it was brought to our notice that the study was a collaborative effort. The error is regretted

Section: General, Science, News Source:
Bengaluru Friday, 2 February, 2018 - 07:04

Isolation could drive tigers to extinction by 2100

There was once a time when tigers roamed the expanse of Asia--from Turkey in the west to the eastern coast of Russia, featuring in many legends and folklores. They once stood for royalty and prosperity. Fast forward to today, these magnificent cats have dwindled in numbers and have lost 93% of what once used to be their home, over the last century alone. While 5,000 to 7,000 tigers roamed the wild in 1998, they are reduced to just about 3500 individuals -- a 50% decline in last three decades! Unsurprisingly, tigers are now an endangered species on the International Union for Conservation of Nature (IUCN) Red List. In a recent study by researchers at the National Center for Biological Sciences, Wildlife Conservation Trust, FERAL and University of Montana, have examined genetic diversity of tigers in India to identify the importance of connected forest corridors to future populations and minimize their risk of extinction in the coming century.

India was once home to a sprawling tiger population. By the end of 19th century, between 50,000 to a lakh tigers were thought to have populated the subcontinent. Even today, the country is home to nearly 65% of the world’s wild tigers. India has identified priority areas called Tiger Conservation Landscapes (TCLs) in historical tiger ranges to save what is left. The TCLs are 40 in number, vary in size and each one is big enough to conserve at least five tigers. However, tigers cross vast landscapes, and about 35% of India’s tigers are estimated to be living outside these protected areas. Since most of these protected areas are sandwiched between dense human settlements, agricultural lands and highways with high traffic density, they are increasingly being disconnected from each other, restricting the movements of animals. And that is a problem, say the researchers of the present study.

“Understanding how different species are impacted by landscape features like roads and agriculture is important to develop conservation strategies that ensure survival of multiple species into the future”, says Ms. Prachi Thatte, a researcher from NCBS, who led this study, talking about the importance of the study published in Elsevier’s journal Biological Conservation.

The researchers conducted the study in central India, in eleven tiger reserves and other potential areas in the state of Maharashtra, Madhya Pradesh and Chhattisgarh.  Expanding cities are resulting in encroachments of these forests for building houses, roads and railways. For example, the national highway 7, that cuts across one such protected area used by tigers as a corridor for movement, is being widened. These developments result in fragmentation of protected areas, restricts the movement of tigers between such areas, isolates small populations leading to inbreeding, low genetic variation and an increase in susceptibility to diseases.

The researchers collected tiger scats in central India, within and outside protected areas, to measure genetic variation  and genetic exchange between populations/areas. The genetic data was also used to infer how different landscape features like roads and railway lines affect connectivity. Using both, genetic data and the inferred effect of landscape variables, they simulated the possible changes in genetic diversity, connectivity and the probability of extinction under various development scenarios in the year 2100.

The results of the study show that today, human settlements and roads with high traffic restrict tiger movement the most. In the future, due to rapid urbanisation, this would worsen, reducing the genetic diversity of tigers in the area. Stepping-stone corridors -- forest area where protection is ensured -- that facilitate movement of tigers would also be insufficient to maintain the current genetic diversity. Although they contribute to 10% higher genetic variation and between 6% to 86% lower extinction probability when compared to areas without these corridors. Large areas of forest have been used for mining, which could lead to 22% higher chance of extinction for the neighboring tigers.

“We found that tiger numbers in small populations fluctuate over years much more than in large populations. The ratio of number of males to females (sex ratio) in the population also fluctuates in small populations. This contributes to the extinction risk of these populations”, says Ms. Thatte, on the findings of the study. 

So, what would help these tigers survive the risk of extinction? “It is important that the Central Indian landscape is managed as a network of Protected Areas inter-connected with corridors. We need informed development plans that consider biodiversity and connected wildlife populations in addition to human development goals”, opines Ms. Thatte. “Protected areas are not currently disconnected, as shown by the genetic data in our study. There is movement of individuals between several of them. Our future simulations suggest that stepping stone corridors are the best way maintain connectivity and also sustain the tiger population increase into the future”, she adds.

This study stresses on the importance of conservation planning on the management of land use and tiger populations. By keeping a close eye on vulnerable tiger populations, the species, as well as it’s landscape can be protected.

Section: General, Science, Ecology, Policy, Deep-dive Source:
Bengaluru Thursday, 1 February, 2018 - 06:16

A new study by researchers from Indian Institute of Technology Bombay, Mumbai has, for the first time, demonstrated an efficient way to convert garden waste into fuel pellets that could be used for cooking.

Many urban households, and a few rural ones, sport a garden in the backyard, often populated with flowering and vegetable plants and some trees. The gardens also are a hotspot for a host of biodiversity, like butterflies, birds, reptiles and rodents, often attracted to the greenery that grows there. Garden owners are also fond of keeping their gardens clean, often trimming the overgrowth and cleaning off fallen leaves, twigs and other biomass. The garden waste that is generated after cleaning is usually burnt or disposed off. What if all that waste needn’t be wasted but can instead be put to good use, by converting it into fuel for cooking?

Scientists from IITB have been exploring ways to do exactly this. In their new study, the scientists have developed a method to convert the garden waste biomass into fuel pellets that could be burnt for usable energy. The fuel pellets that are formed could be used in stoves as an efficient substitute to firewood and other fuels.

Various parameters, like moisture content, milling size and die size, of the pellets that were formed were further probed for optimal performance using regression models- a statistical tool. Their study showed that an increase in the moisture content of the biomass affected the durability of the final product. It also revealed a biomass moisture content of around 6% and a die size of 15mm were ideal for the pellets formed to perform efficiently. The pellets were also probed under a Scanning Electron Microscope to study the effect of moisture on the final product, which showed the pellet particles sticking closely together when the moisture content in the biomass was considerably low.

If commercialized, the technology could be used as a suitable substitute for cooking gas and other fuels in low income households.

“We deduced from the combustion test that garden waste pellets may be conveniently used in a residential cookstove” claim the researchers about their new technology

Section: General, Science, Technology, News Source:
Pune Thursday, 1 February, 2018 - 05:40

Our climate system is complex and intricate, and depends on a wide range of components that make it up -- air, temperature, pressure, moisture, etc. Any small change in the any of these will have a domino effect, leading to massive implications. One such component that is gaining importance is ‘carbonaceous aerosol’ which are fine particulates in the atmosphere. While scientists have found that aerosols contribute to the changing climate, a new study by researchers at the Indian Institute of Tropical Meteorology (IITM), Pune, has explored how these carbonaceous aerosols affect the different layers of our atmosphere. The black carbon aerosols and organic carbon aerosols togetherly known as carbonaceous aerosols.

Aerosols are diverse and widespread. Vehicular emissions, exhaust from coal-based power plants and industries, forest fires, residential biofuel and fossil-fuel combustion--all lead to aerosol emissions. Among the different types of aerosols, carbonaceous aerosols are important as they can bring about climate change, and alter the energy balance in the atmosphere as they absorb and scatter solar radiations, and affect precipitation patterns around the globe.

“Black carbon aerosols produce local warming”, says Dr. Suvarna Fadnavis from IITM, Pune, who is also the author of the study published in the journal Atmospheric Chemistry and Physics. The study focuses on the impact of carbonaceous aerosols on the thermal structure of the upper troposphere and lower stratosphere (UTLS)--A atmospheric region pertaining to higher altitudes (12-18 km), in South Asia and Southeast Asia. It also takes into effect the underneath monsoon circulation, for which analysis has been done during the monsoon season, from 20 years of global model simulations.

The researchers performed the global atmospheric Chemistry model simulations on High Performance Computer (HPC) system (at IITM) to study the impact of emissions of carbonaceous aerosols. The model accounts the emission of sulphate, black carbon, particulate organic matter, sea salt and mineral dust aerosols. Human induced activities and biological activities were also taken into account in these simulations.

The researchers found that emissions of black carbon aerosols are lifted up from the Earth’s surface to the upper troposphere (near 12-18 km) by the monsoon circulation. This causes instabilities in the mid to upper troposphere as the aerosols gradually spread over the Tibetan plateau and Indo-Gangetic plains, producing significant warming near 7-12 km, (400-200 hPa; 1 hectopascal = 100 Pascal).  They also found that the emission of organic carbon aerosol was higher than black carbon aerosols over Asia, and the UTLS was heating up because of the higher absorption capacity of black carbon aerosols over organic carbon aerosols.

The study reveals that the aerosols have manifold implications, ranging from bringing about a change in the rainfall patterns and causing abnormal heating of the atmosphere through radiation. Interestingly, this heating, in turn, accelerate the upward movement of the aerosols into the next layer of the atmosphere, the stratosphere (~20km), which also heats up as a result. Rainfall pattern gets affected due to the impact on the cirrus clouds -- high level clouds in the atmosphere, and due to the formation of cloud ice near the tropopause (the interface between the troposphere and stratosphere). The impacts are more pronounced over the Tibetan plateau and the Indo-Gangetic plains, where their concentration and emission rates are relatively much higher.

“To study the climate change due to carbonaceous aerosols one would need minimum of 60 years simulations, whereas our study is only for 20 years. However, many recent studies have said that carbonaceous aerosols can substantially contribute to the climate forcing and their impacts on local meteorology and monsoon circulation are large”, says Dr. Fadnavis, talking about the importance of this study. In a planet that is fighting its battles of climate change at different levels, the implication of increasing carbonaceous aerosols is yet another challenge to knock down.

Section: General, Science, Deep-dive Source:
Bengaluru Wednesday, 31 January, 2018 - 17:12

On January 31st starting at around 17:18 IST, India will witness a rare celestial event-- a total lunar eclipse coinciding with a supermoon and a blue moon.

A lunar eclipse occurs when the earth comes in between the sun and the moon, casting its shadow on the moon. This is called a total lunar eclipse.

A total lunar eclipse is also called a blood moon since antiquity, because of the reddish brown hue rendered during the eclipse. As sunlight passes through earth’s atmosphere the white light is broken down into its constituent colors, and red light is scattered onto the Moon’s surface, giving it the reddish brown hue observed during a total lunar eclipse, and earning it the name
blood moon.

This time however, the blood moon also coincides with the supermoon phenomenon, which occurs when the full moon coincides with the perigee of the Moon, which is closest distance the Moon reaches to the Earth on its elliptical orbit. During a supermoon, the Moon generally appears slightly larger in the night sky.

The total lunar eclipse will also coincide with the blue moon- a name given to the second full moon of a month in the English calendar. This makes the event quite rare, with the last such blood moon and blue moon occuring occurring 36 years ago on December 30, 1982.

On the 31st, in India, the eclipse will start at around 17:18. The moon will be completely eclipse by around 18:20 and the total eclipse will last till around 19:37. The moon will become completely visible again by around 20:40, with the eclipse lasting for about 1 hour and 16 minutes.

Section: General, Science, News Source:
Panaji Wednesday, 31 January, 2018 - 12:18

After a successful first edition, the second edition of the Nobel Prize Series-India is all set to kick off tomorrow at the Kala Academy in Panaji, Goa. The event is jointly organized by the Department of Biotechnology (DBT), Ministry of Science and Technology, India along with the Government of Goa and Nobel Media AB.

Initiated in 2017, after a formal MoU between DBT and Nobel Media AB, the Nobel Prize Series is a unique annual event that will host a combination of lectures, conferences, exhibitions, roundtables and other meeting spaces, providing a unique opportunity for students, researchers and the common man to interact with Nobel Laureates and eminent scientists from India and abroad. The Nobel Prize Series aims to stimulate creative thinking among the attendees by bringing together Nobel Laureates, other experts and lifelong learners. It may be recalled that the first edition of the series was held as a part of Vibrant Gujarat in Gandhinagar, Gujarat, in 2017 and saw participation from the enormous student and researcher community from the country.

“The Nobel Prize Series provides a great platform for all audiences interested in science, by giving an opportunity to learn from Nobel Laureates. The talks, exhibitions and lectures pave a way for inspiring many young minds to pursue science education and bring the best out of them” remarks Prof. K. VijayRaghavan, Secretary, DBT talking about the importance of the programme.

This year, the event will see the inaugration ceremony of the Nobel Prize Series - India 2018 by the Hon'ble Chief Minister of Goa, Mr. Manohar Parrikar, a science exhibition and an interactive display of past Nobel Laureates and their work and discoveries, along with a history of the Nobel Prize. This will be followed by an interactive round table on “What Industry can do for scientists and scientists for Industry - and why” with the Nobel Laureates, industry heads, educationists, scientists and government officials participating in it.

This year will also feature, Ek Pradarshini – The Best of Indian Science, a creative showcase of some of the best scientists from the diverse field of science and engineering India has produced. The exhibition will showcase their contributions, which have added to the global knowledgebase of science and helped advance their respective fields immensely. 


Section: General, Science, News, Events Source: Link
Mumbai Tuesday, 30 January, 2018 - 22:31

Adding chaos helps finding better solutions to multi-reservoir irrigation systems, says an IIT Bombay study

Finding the best possible solution to achieve multiple goals simultaneously are of great relevance in our everyday life. Take for example, the irrigation canals in agricultural fields, where it is desirable to ensure that the demand is met for all the areas supplied by the reservoirs. What makes this a complicated problem is that we need to balance both the demand, which depends on the type of crops grown, and the supply that depends on the inflow into the reservoirs.  We would like to plan which crops can be grown and in how much area in a given region, depending on the supply capacity and pattern of the reservoir system. In a study, researchers Dr. R. Arunkumar and Prof. V. Jothiprakash of the Indian Institute of Technology Bombay (IITB) have proposed a novel algorithm which can help solve such problems when systems with multiple components are involved.

"Optimizing the operations of a reservoir in itself is complicated because of the uncertainty in the inputs, conflicting and competing objectives, etc. Multi-reservoir systems, with more number of variables to be optimized and large number of physical, technical, legal and social constraints are further complex,” explains Prof. Jothiprakash. To give the best solution taking into consideration all these constraints, multi-objective evolutionary algorithms are the most commonly used.

Multi-objective evolutionary algorithms try to solve problems that satisfy many objectives and are inspired by biological evolution. They start with a initial set of solutions (initial population) which is then allowed to ‘evolve’ under some conditions. Solutions produced after each iteration is tested for optimality. The population is made to ‘evolve’ until an optimal or close to optimal solution set is achieved. If this computation gets stuck at a suboptimal solution, the process will be repeated with a different initial population. As one can see, this is a computationally tedious process and we may not always end up with the best solution.

Here is where the modifications proposed by the researchers of this study come into play.  They have suggested the use of chaotic algorithms--algorithms which are very sensitive to changes in initial variables--along with a conventional multi-system evolutionary algorithm that works as above. Studies in the past have shown that using chaotic algorithms have improved solutions with single-objective problems. “Most of the previous studies utilized chaos in only generating the initial population. All those studies reported that the global optimal solutions were obtained more readily and rapidly, when chaos is incorporated,” says Dr. Arunkumar.  In this study the chaos algorithm was used not only in generating initial population but also in other steps of evolutionary algorithm.

The researchers also ran simulations using data from Kukadi Irrigation Project (KIP) in Maharashtra, a multi-reservoir system comprising of five reservoirs, to test the efficiency of the modified algorithm. They used the algorithm to find optimal crop plan and water allocation in regions which are dependent on KIP for irrigation. They found that the solutions produced by their algorithm, even though were only slightly better than the conventional algorithms in terms of net benefits and crop area allocation, took far less number of iterations.

“Though there is no significant difference in the optimal solutions obtained from other algorithms, the number of generations taken by the chaotic evolutionary algorithm is much less than conventional algorithms. This shows that the chaotic characteristics may enhance optimization algorithms and make them more successful,” says Dr. Arunkumar about the observed results.

So, can we apply this algorithm to address inefficiencies in our irrigation systems? Not yet, say the researchers. “Real time reservoir operation is more challenging since we will need a system to predict the inflow in real time, along with the reservoir operation model,” says Prof. Jothiprakash. This study is a step in the right direction where we bank on algorithms to help us design public policies and efficient systems.

Section: General, Science, Technology, Deep-dive Source: