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This study aims to present the numerical analysis of exergy transfer and irreversibility through the discrete filling of high-porosity aluminum metal foams inside the horizontal pipe.

In this study, the heater is embedded on the pipe’s circumference and is assigned with known heat input. To enhance the heat transfer, metal foam of 10 pores per inch with porosity 0.95 is filled into the pipe. In filling, two kinds of arrangements are made, in the first arrangement, the metal foam is filled adjacent to the inner wall of the pipe [Model (1)–(3)], and in the second arrangement, the foam is located at the center of the pipe [Models (4)–(6)]. So, six different models are examined in this research for a fluid velocity ranging from 0.7 to7 m/s under turbulent flow conditions. Darcy Extended Forchheimer is combined with local thermal non-equilibrium models for forecasting the flow and heat transfer features via metal foams.

The numerical methodology implemented in this study is confirmed by comparing the outcomes with the experimental outcomes accessible in the literature and found a fairly good agreement between them. The application of the second law of thermodynamics via metal foams is the novelty of current investigation. The evaluation of thermodynamic performance includes the parameters such as mean exergy-based Nusselt number (Nu_e), rate of irreversibility, irreversibility distribution ratio (I_DR), merit function (MF) and non-dimensional exergy destruction (I^*). In all the phases, Models (1)–(3) exhibit better performance than Models (4)–(6).

The present study helps to enhance the heat transfer performance with the introduction of metal foams and reveals the importance of available energy (exergy) in the system which helps in arriving at optimum design criteria for the thermal system.

The uniqueness of this study is to analyze the impact of discrete metal foam filling on exergy and irreversibility in a pipe under turbulent flow conditions.

India became a NWS (Nuclear Weapons State) most reluctantly in May 1998 despite her demonstration of nuclear weapons capability 24 years earlier in May 1974. Having assumed the new status as the sixth overt nuclear weapons state, India also declared her principled policy governing use of nuclear weapons in the event of a national security threat. The Indian Nuclear Doctrine was called “minimum deterrence” by the BJP-led NDA government, but the Congress-led UPA government in 2004 renamed it as “credible deterrence.”

But the heart of the vibrant Indian nuclear doctrine is its commitment to No First Use (NFU) of nuclear weapons. Nuclear weapons were invented by the United States (U.S.). First-ever use of atom bomb is also made by the Americans and a philosophic foundation for the discussion on NFU was also laid in the U.S. However, having put the NFU in the philosophic parlance, the U.S. in the Cold War International environment professed the doctrine for First Use (FU) of nuclear weapons. It is China that made a first public commitment to the NFU after it became the fifth nuclear weapons state.

This chapter proposes to discuss Indian commitment to NFU as a first step on the long path toward global nuclear disarmament—or No Use (NU) of nuclear weapons. India saw Partial Test Ban treaty of 1963 as a step toward NU and also saw the discussions on NPT as another step toward nuclear disarmament as much as it wanted the big powers to see the CTBT too as a device aimed at putting world into NU bind. West, led by the U.S., was however only interested in using the CTBT to deny nuclear weapons status to threshold states, particularly India.

As a self-declared nuclear weapons state, India has, in nuclear doctrine, committed itself to nuclear disarmament. Can there be an international treaty between the declared nuclear weapons states? Can India and Russia come together on the issue? Can they convince China to join? With three Asian nuclear weapons states committing themselves to NFU, U.S. can see economic sense in an international treaty on NFU. Is it possible to create a global public opinion in favor of NU of nuclear weapons? The questions will be answered based on research conduct on the subject.

Is India backing out from its commitment to No First Use (NFU) of nuclear weapons (NWs)? It was a highly debated issue in newspapers and electronic media in August 2019. What triggered this question? In this chapter, I intend to, after explaining significance of NWs in Indian defence strategy and nuclear doctrine that includes Indian commitment to NFU of NWs, answer the two questions raised in reverse order briefly.

This paper aims to discuss about the two-dimensional numerical simulations of fluid flow and heat transfer through high thermal conductivity metal foams filled in a vertical channel using the commercial software ANSYS FLUENT.

The Darcy Extended Forchheirmer model is considered for the metal foam region to evaluate the flow characteristics and the local thermal non-equilibrium heat transfer model is considered for the heat transfer analysis; thus the resulting problem becomes conjugate heat transfer.

Results obtained based on the present simulations are validated with the experimental results available in literature and the agreement was found to be good. Parametric studies reveal that the Nusselt number increases in the presence of porous medium with increasing thickness but the effect because of the change in thermal conductivity was found to be insignificant. The results of heat transfer for the metal foams filled in the vertical channel are compared with the clear channel in terms of Colburn j factor and performance factor.

This paper serves as the current relevance in electronic cooling so as to open up more parametric and optimization studies to develop new class of materials for the enhancement of heat transfer.

The novelty of the present study is to quantify the effect of metal foam thermal conductivity and thickness on the performance of heat transfer and hydrodynamics of the vertical channel for an inlet velocity range of 0.03-3 m/s.

The compressive strength of concrete depends on many interdependent parameters; its exact prediction is not that simple because of complex processes involved in strength development. This study aims to predict the compressive strength of normal concrete and high-performance concrete using four datasets.

In this paper, five established individual Machine Learning (ML) regression models have been compared: Decision Regression Tree, Random Forest Regression, Lasso Regression, Ridge Regression and Multiple-Linear regression. Four datasets were studied, two of which are previous research datasets, and two datasets are from the sophisticated lab using five established individual ML regression models.

The five statistical indicators like coefficient of determination (R²), mean absolute error, root mean squared error, Nash–Sutcliffe efficiency and mean absolute percentage error have been used to compare the performance of the models. The models are further compared using statistical indicators with previous studies. Lastly, to understand the variable effect of the predictor, the sensitivity and parametric analysis were carried out to find the performance of the variable.

The findings of this paper will allow readers to understand the factors involved in identifying the machine learning models and concrete datasets. In so doing, we hope that this research advances the toolset needed to predict compressive strength.

This chapter justifies India’s acquisition of nuclear weapons on the basis of an ancient Roman dictum: Si vis pacem, para bellum, which means, ‘if you want peace, prepare for war’. However, Indian leaders were far more imbued with idealism than realism. Nehru’s successors were not able to overcome Nehru’s idealistic commitment to use nuclear technology for peaceful purposes alone.

However, the government led by the BJP changed Indian nuclear policy by conducting five nuclear tests in May 1998 and declaring India as a Nuclear Weapons State (NWS). India also came out with its nuclear doctrine.

This chapter discusses the basic principles of the Indian nuclear doctrine. Though there are several principles of the doctrine, only such principles which have a bearing on the ultimate goal of achieving nuclear disarmament are discussed in this chapter. India has pledged not to use nuclear weapons ‘against states which do not possess nuclear weapons, or are not aligned’ with other NWS. India adheres to the concept of no first use (NFU) of nuclear weapons. This is the heart of the nuclear doctrine. The principle of NFU says that the nation would resort to the use of nuclear weapons only as a weapon of self-defence and only in a second strike.

India as a reluctant NWS has also committed its nuclear doctrine to ‘global, verifiable and non-discriminatory nuclear disarmament’ as a national security objective. Indian nuclear doctrine is conducive in promoting nuclear disarmament. The chapter also proposes an international treaty around NFU as a first step towards nuclear disarmament.