Department of Management Studies

<p>IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.</p>

<p>IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD</p>

<p>It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.</p>

IIT Madras

Water mist, as an effective fire suppressant, works on the principle of oxygen dilution and flame cooling. The recent re-emergence of water mist is attributed to its candidacy as a Halon-replacer, for Halon is being phased out. Also, water mist systems use less water as compared to sprinklers. Deep insight into the physical process of mist-fire interaction is lacking but is crucial for developing suppression systems. The present work concerns the interaction between water mist and a flame. A methane fed circular burner generates a diffusion flame. Pressurized water fed into a Delavan nozzle generates the water mist and is positioned right above the burner at a fixed height. A glass cubicle encloses the entire system to isolate experiments from the surroundings. A camera mounted on a traverse captures the light scattered by those droplets passing through a laser sheet generated from a Nd:YAG laser. The variation of parameters includes spray injection pressures and heat release rates from the burner. Employing the PIV technique yielded the velocity field of the mist with and without the flame. The velocity field results indicate that the droplets are slowed down very close to the nozzle due to the flame. Also, a recirculation zone is observed at the periphery of the spray cone, very close to the nozzle. It is a toroidal vortex that is generated due to the interaction, and the droplets thrown away from the spray cone gets trapped into this flow. The flow structure is present in a highly turbulent region and is identifiable only in the mean flow. Another finding is that close to the burner, fine droplets that could make it to the base, gets entrained into the flame. It is expected that the droplets to be greatly entrained into the larger flame, as the entrainment is stronger for large flame, compared to the smaller flame. But the PIV results indicate otherwise. Also, an increased droplet number density near the spray edge indicates widening of the spray in the presence of a flame. These results will add to the repository of data that can validate various fire suppression models being developed. © 2018 Solar Turbines Incorporated.

World University root node

ICLASS 2018 - 14th International Conference on Liquid Atomization and Spray Systems

Velocity and droplet concentration measurements of downward directed water mist suppressing a diffusion flame

The urbanization trend and the prevailing energy crisis in India, makes it important to study the potential of IoT technology in the Indian buildings market. This research work proposes a systems dynamics model of IoT based climate control systems diffusion in Intelligent Buildings. The modeling process leverages the generic Bass model of technology diffusion and augments it with causal loops based on the enablers and barriers to IoT diffusion in buildings identified through literature review. The model encompasses the technological, social, financial, business, regulatory and environmental aspects of the system, and uses stock-flow concepts to represent their dynamic interplay. The model will be useful to value chain players in the construction sector by providing them support for strategic decision-making concerning market entry and new product development. It will also help policy makers to assess industry readiness to tackle the prevailing energy crisis and devise strategies to mitigate it. © 2020, IFIP International Federation for Information Processing.

IFIP Advances in Information and Communication Technology

IoT Based Climate Control Systems Diffusion in Intelligent Buildings - A System Dynamics Model

Data from Global Positioning Systems (GPS) and fare-meters in For-Hire vehicles (FHVs) have been used for various applications - both in research as well as organizational decision-making. The utility of such exercises largely depend on the accuracy of the data. This study looks at an environment where the data is partially mislabeled. Specifically, we take a common real-world setting where vehicle operators choose to render transportation services to customers without the use of a fare-meter, often by negotiating a fixed rate with the customer. This practice, which to different degrees, has been observed and documented across urban areas in the world, leads to various undesirable effects. In this study, we seek to identify cases of such behavior in the dataset. Typically, a supervised learning classifier could be built to predict the occupancy status from GPS traces, which can then be used, to look for anomalies between the predicted and stated behaviors. However, in our case the training dataset also contains instances of incorrect tagging. We address this problem by casting it as one of learning from Positive and Unlabeled instances (PU Learning) . This is owing to the fact that we observe the phenomenon of one-sided label noise, where trips tagged 'vacant' by the taximeter could be truly vacant or occupied, whereas trips tagged 'occupied' are expected to be occupied in reality as well. To support this novel formulation, we apply three state-of-the-art PU Learning algorithms on a real-world trajectory data set from an organization plying 170 active vehicles over a period of two months. We compare these to the baselines of standard supervised learning. Validation is carried out by the organization through alternate channels of investigation which is not indicated in the data set. The results show that the PU Learners provide a significant improvement in classification across a range of metrics when compared to the baseline approaches. This translates to a significant increase in identifying or reclassifying the mislabeled rides. © 2021 ACM.

Department of Computer Science and Engineering

Department of Humanities and Social Sciences

ACM International Conference Proceeding Series

Inferring customer occupancy status in for-hire vehicles using PU Learning

Department Of Biotechnology

Curcumin augments therapeutic efficacy of TRAIL-based immunotoxins in leukemia

This study examines the impact of concentrated founder ownership on related party transactions (RPTs) for Indian firms. We find that concentrated founder ownership is positively related to RPTs and is more likely to encourage RPTs that are beneficial for the minority shareholders. We also observe that RPTs are associated with higher firm value. This relationship is more pronounced for business group firms and firms with more highly concentrated founder ownership. We show that the reputation incentive plays a very important role in founders’ decisions, and they use RPTs as an efficient transaction mechanism. © 2020 Elsevier B.V.

Research in International Business and Finance

Does Concentrated Founder Ownership Affect Related Party Transactions? Evidence from an Emerging Economy

In this paper, we develop branch-and-bound algorithms for objectives such as sum of weighted flowtime, weighted tardiness and weighted earliness of jobs, for an m- machine no-wait (continuous) flowshop. We believe that there has been no prior work on exact algorithms for this problem setup with a variety of objective functions. For the interest of space, we confine our discussion to a subset of certain combination of these objectives and the extension to other objective combinations is quite straight-forward. We explore the active nodes of a branch-and-bound tree by deriving an assignment-matrix based lower bound, that ensures one-to-one correspondence of a job with its due date and weight. This idea is based on our earlier paper on general m- machine permutation flowshop (Madhushini et al. in J Oper Res Soc 60(7):991–1004, 2009) and here we exploit the intricate features of a no-wait flowshop to develop efficient lower bounds. Finally, we conclude our paper with the numerical evaluation of our branch-and-bound algorithms. © 2020, Indian Academy of Sciences.

Sadhana - Academy Proceedings in Engineering Sciences

Branch-and-bound algorithms for scheduling in an m-machine no-wait flowshop

<h3>Aim</h3><p>Mesenchymal stem cells (MSCs) are immunomodulatory, non-teratogenic and multipotent alternatives to embryonic or induced pluripotent stem cells (ESCs or iPSCs). However, the potency of MSCs is not equivalent to the pluripotency of ESCs or iPSCs. We used CHIR 99021 to improve current protocols and methods of differentiation for the enhanced transdifferentiation potency of MSCs.</p><h3>Main Methods</h3><p>We used Flurescence activated cell sorter (FACS) for MSC immunophenotyping and biochemical assay for demonstrating the trilineage potential of MSCs. We used real-time polymerase chain reaction, immunocytochemistry and Western blotting assay for analyzing the expression of lineage-specific markers.</p><h3>Key Findings</h3><p>CHIR 99021 treatment of MSCs resulted in enhanced transdifferentiation into neurological, hepatogenic and cardiomyocyte lineages with standardized protocols of differentiation. CHIR 99021–treated MSCs showed increased nuclear localization of β-catenin. These MSCs showed a significantly increased deposition of active histone marks (H3K4Me3, H3K36Me3), whereas no change was observed in repressive marks (H3K9Me3, H3K27Me3). Differential methylation profiling showed demethylation of the transcription factor OCT4 promoter region with subsequent analysis revealing increased gene expression and protein content. The HLA-DR antigen was absent in CHIR 99021–treated MSCs and their differentiated cell types, indicating their immune-privileged status. Karyotyping analysis showed that CHIR 99021–treated MSCs were genomically stable. Teratoma analysis of nude mice injected with CHIR 99021–treated MSCs showed the increased presence of cell types of mesodermal origin at the site of injection.</p><h3>Significance</h3><p>MSCs pretreated with CHIR 99021 can be potent, abundant alternative sources of stem cells with enhanced differentiation capabilities that are well suited to cell-based regenerative therapy.</p>

Glycogen synthase kinase 3β inhibitor- CHIR 99021 augments the differentiation potential of mesenchymal stem cells

User-centric, localized energy and comfort management solutions that are essential in commercial buildings are realized by IoT enabled building management systems, involving networked sensors and artificial intelligence-based data processing. This paper employs the Delphi method to identify the major issues concerning IoT adoption in India and examines these across the value chain, specific to energy and comfort management in intelligent buildings. The Delphi exercise involved 3 expert-panels, consisting of a total of 24 subject matter experts representing all important stakeholders across the intelligent building value chain. A total of 140 issues have been identified, grouped across 8 themes, and ranked, leading to the development of an ‘IoT adoption index’. A subset of the issues has been identified using two inputs from the literature, viz., key performance indicators of intelligent buildings and the business model canvas. The results can be practically used by the stakeholders while evaluating IoT systems for deployment in their projects. Further, the results should be useful in the context of intelligent buildings also in other emerging economies having similar climatic conditions. © 2020 Informa UK Limited, trading as Taylor & Francis Group.

Intelligent Buildings International

Issues concerning IoT adoption for energy and comfort management in intelligent buildings in India

In a supply chain coordinated by a revenue sharing contract, under-reporting of sales revenue has been a common practice amongst retailers who always have private information about the market demand. In this article, we aim to design a mechanism to mitigate this problem. One may design a contract to elicit truthful information from the retailer while maximizing supplier's payoff. However, we find that such contracts fail to coordinate the supply chain, when the market demand is high. Hence, we study an audit-based revenue sharing contract. First, we design a laboratory experiment to investigate the impact of retailer's decisions on the subsequent choices made by the supplier. We find that the audit probability chosen by the supplier increases with the gap between retailer's order quantity and the sales reported by the retailer. We follow this up with a simulation experiment which incorporates the findings of our laboratory experiment. Audit cost and the penalty announced by the supplier for not reporting true sales turned out to be important in making decisions for both the players. We also find the threshold auditing cost beyond which auditing is not economically viable for the supplier. © 2020 International Journal of Mathematical, Engineering and Management Sciences.

Department Of Physics

Fulltext

International Journal of Mathematical, Engineering and Management Sciences

Designing a revenue sharing contract under information asymmetry

3D pitch rotation of microparticles and cells assumes importance in a wide variety of applications in biology, physics, chemistry and medicine. Applications such as cell imaging and injection benefit from pitch-rotational manipulation. Generation of such motion in single beam optical tweezers has remained elusive due to the complexities of generating high enough ellipticity perpendicular to the direction of propagation. Further, trapping a perfectly spherical object at two locations and subsequent pitch rotation hasn't yet been demonstrated to be possible. Here, we use hexagonal-shaped upconverting particles and single cells trapped close to a gold-coated glass cover slip in a sample chamber to generate complete 360 degree and continuous pitch motion even with a single optical tweezer beam. The tweezers beam passing through the gold surface is partially absorbed and generates a hot-spot to produce circulatory convective flows in the vicinity which rotates the objects. The rotation rate can be controlled by the intensity of the laser light. Thus such a simple configuration can turn the particle in the pitch sense. The circulatory flows in this technique have a diameter of about 5 μm which is smaller than those reported using acousto-fluidic techniques. © 2020 Optical Society of America.