Stemming the tide: Does climate risk affect M&A performance?

We examine the effect of climate change risks (CCR) on firms' decision of engaging in mergers and acquisitions (M&A) and M&A performance. In this study we use the responses by firms on ‘climate change-related risks and opportunities’ of the CDP survey and 1,372 deals of listed US firms during 2010-2020. Consistent with risk vulnerability theory, our evidence indicates that firms with higher CCR have a lower probability of engaging in M&As. After controlling for possible endogeneity, our results also indicate that if acquirers with higher climate change risks choose to engage in M&A, it significantly reduces the announcement returns. These findings suggest that extant measures of climate change risks should be rethought when evaluating M&A efficiency. More broadly, our paper provides causal evidence that managers need to integrate CCR into their formal risk management systems to avoid unsuccessful M&As

Implications of time-dependent molecular chemistry in metal-poor dwarf stars

Binary molecules such as CO, OH, CH, CN, and C$_2$ are often used as abundance indicators in stars. These species are usually assumed to be formed in chemical equilibrium. The time-dependent effects of hydrodynamics can affect the formation and dissociation of these species and may lead to deviations from chemical equilibrium. We aim to model departures from chemical equilibrium in dwarf stellar atmospheres by considering time-dependent chemical kinetics alongside hydrodynamics and radiation transfer. We examine the effects of a decreasing metallicity and an altered C/O ratio on the chemistry when compared to the equilibrium state. We used the radiation-(magneto)hydrodynamics code CO5BOLD, and its own chemical solver to solve for the chemistry of 15 species and 83 reactions. The species were treated as passive tracers and were advected by the velocity field. The steady-state chemistry was also computed to isolate the effects of hydrodynamics. In most of the photospheres in the models we present, the mean deviations are smaller than $0.2$ dex, and they generally appear above $\log{\tau} = -2$. The deviations increase with height because the chemical timescales become longer with decreasing density and temperature. A reduced metallicity similarly results in longer chemical timescales and in a reduction in yield that is proportional to the drop in metallicity; a decrease by a factor $100$ in metallicity loosely corresponds to an increase by factor $100$ in chemical timescales. As both CH and OH are formed along reaction pathways to CO, the C/O ratio means that the more abundant element gives faster timescales to the constituent molecular species. Overall, the carbon enhancement phenomenon seen in very metal-poor stars is not a result of an improper treatment of molecular chemistry for stars up to a metallicity as low as [Fe/H] = $-3.0$.Comment: 29 page

Implementation of using classification Data Mining Techniques for Software Cost Estimation

Cost estimation is one of the biggest problems faced by software industry. It is necessary to have accurate cost estimation in order to conduct well budget. Under-estimation may lead to unexpected increase in budget, delay of project completion or its low quality, while over-estimation may lead to losing business opportunities. In this dissertation the idea of building data mining techniques into existing software cost estimation model such as COCOMO II model is implemented. Data mining allows users to analyze data from many different dimensions or angles, categorize it, and summarize the relationships identified

An Ant Colony Optimization based Routing Techniques for VANET

With number of moving vehicles, vehicular Ad Hoc Network (VANET) is formed. These are provided with the wireless connections. Among various challenges in the VANET such as security and privacy of the messages, data forwarding is also considered as a major challenge. The effective communication is mainly depends on the how safely and fast the data is being forwarded among the vehicles. Data forwarding using Greedy mechanism suitable for routing in the VANETs, it depends only on the position of nodes and also data forwarding is done with minimum number of hops. In this paper, Position based GPCR and topology based DYMO routing protocol are adapted to make the use of Ant Colony Optimization (ACO) procedures. The resulting bio-inspired protocols, ACO_GPCR and ACO_DYMO had its performance evaluated and compared against existing GPCR and DYMO routing protocols. The obtained results suggest that making the use of ACO algorithm make these protocols more efficient in terms of Delay, Jitter, Packet Delivery Ratio and energy consumption