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The objectives of this paper are to assess the sliding wear response of a zinc‐based alloy over a range of sliding speeds and pressures in oil‐lubricated condition with respect to a cast iron, to understand the role of different microconstituents in controlling the observed wear behaviour and to examine various operating material removal mechanisms.

Sliding wear tests have been carried out using a pin‐on‐disc machine in oil‐lubricated condition at different speeds and pressures. The wear response has been explained in terms of specific nature of various microconstituents of the specimen materials and substantiated through the characteristics of wear surfaces, subsurface regions and debris particles.

The wear rate increased with the sliding speed while load produced a mixed influence. Further, the friction coefficient and frictional heating were influenced by the test duration, load and speed in a mixed manner. Moreover, the zinc‐based alloy attained lower wear rate but higher friction coefficient than that of the cast iron while frictional heating followed a mixed trend.

The paper further establishes a zinc‐based alloy as a potential substitute material system to a well‐known cast iron in tribological applications and enables further understanding of the wear mechanisms.

The present paper assesses the sliding wear performance of a lighter zinc‐based alloy as an effective potential substitute material system to cast iron in tribological applications. An attempt has also been made to understand the role played by different microconstituents in controlling the wear behavior and substantiate the wear response through the characteristics of wear surfaces, subsurface regions and debris.

The purpose of this paper is to understand the sliding wear response of a cast iron as influenced by applied load and changing concentration of solid lubricant (graphite) particles in oil lubricant, and operating material removal mechanisms in different sets of experimental conditions.

The sliding wear response of a grey cast iron has been examined as a function of test environment and load. Properties evaluated were wear rate, friction coefficient and frictional heating. The wear behaviour of the samples has been substantiated through the characteristics of their wear surfaces, subsurface regions and debris particles.

The wear rate and frictional heating increased with load while friction coefficient was affected in an opposite manner. The presence of oil lubricant led to a substantial improvement in wear response (in terms of decreasing wear rate, friction coefficient and frictional heating) while the presence of graphite particles in the oil lubricant proved to be still better. A critical content of graphite in the oil lubricant becomes most effective towards improving the wear response of the samples. Formation of dark patches on the wear surface, substantial subsurface deformation and fine debris led to improved wear response.

The study enables one to understand the wear behaviour of a cast iron as influenced by the changing concentration of solid lubricant (graphite) particles in the oil lubricant. It also enables one to understand the operating material removal mechanisms responsible for the observed wear characteristics of the samples under varying test conditions. The investigation helps one to see that only a critical concentration of the solid lubricant particles in oil can lead to the best wear performance of materials.

From a practical standpoint, the observations made here gain importance from the fact that solid lubricants are added frequently in oil in engineering applications but it becomes imperative to understand that only a critical concentration can lead to the best wear behaviour of materials.

The purpose of the paper is to assess the influence of the volume fraction solid lubricants like talc lead and graphite in oil separately and in combination towards controlling the sliding wear behaviour of a grey cast iron and understand the factors controlling the response of the material in a given set of experimental conditions.

The composition of the lubricating medium (oil) has been changed by dispersing 5 per cent graphite, talc and lead particles separately and in combination. Sliding wear tests were conducted on grey cast iron samples over a range of applied pressures. Parameters determined were wear rate and frictional heating. The wear behaviour of the samples was further substantiated through the features of wear surfaces, subsurface regions and debris particles. Material removal mechanisms and factors responsible for a specific response of the samples have also been analysed.

The wear rate increased with increasing applied pressure. Addition of graphite and lead to the oil separately or in combination brought about a reduction in the wear rate of the samples; talc and talc + lead produced a reverse trend. Temperature near the specimen surface increased with test duration and applied pressure. The test environment influenced the frictional heating in a manner similar to that of the wear rate. Adhesion and abrasion were observed to be the operating material removal mechanisms. Smearing of the solid lubricating phase and delamination resulting from cracking tendency also controlled the wear response.

Oil is a very popular lubricant used in engineering applications involving friction and wear. Solid lubricants are used along with the oil. The nature, characteristics and content of the solid lubricants very much control the performance. Limited information is available pertaining to assessing the influence of the type and fraction of solid lubricants in the oil towards controlling the wear behaviour of cast irons (popularly known tribomaterials). The present study enables to understand the effectiveness of talc, lead and graphite in oil towards governing the wear characteristics of cast iron and analyse wear mechanisms and controlling parameters.

Graphite and talc are available in nature in abundance. Graphite is a popularly known solid lubricant, while talc is less explored. Lead is also well-known as a solid lubricant but poses health hazard in practice due to its toxic nature. The present study explores the lubricating capability of talc when mixed with oil separately or in combination with lead and graphite towards controlling the wear response of a grey cast iron. It enables to understand the factors responsible for the specific response of talc.

Assessment of the lubricating potential of talc as a possible substitute to lead is important in view of the toxic nature of the latter. If successful, the exercise could enable to replace lead with talc.

The present manuscript is an original piece of the author's research work.

Describes a set of re‐engineering strategies that critically examine current business policies, practices and procedures (3Ps), rethink these 3Ps and then redesign some mission‐critical “products, processes, and services.” The term process improvement implies that the change or effort is directed towards an array of re‐engineering strategies. Process improvement efforts are categorized into four primary re‐engineering strategies: a set of continuous process improvement (CPI) tactics, a set of restructuring tactics, a set of organizational traits, and a set of renovation tactics. Discusses how these four re‐engineering strategies can be logically combined in a concurrent fashion to achieve significant process improvements. Introduces two new hybrid re‐engineering strategies for process improvements that have been found quite useful at Electronic Data Systems (EDS) Accounts.

The purpose of this paper is to design an electromechanical actuator which can inherently tolerate a stuck or loose failure without any need for fault detection isolation and reconfiguration.

Generalized design methodology for a thrust vector control application is adopted to reduce the design iterations during the initial stages of the design. An optimum ball screw pitch is selected to minimize the motor sizing and maximize the load acceleration.

A high redundancy electromechanical actuator for thrust vector control has lower self-inertia and higher reliability than a direct drive simplex configuration. This configuration is a feasible solution for thrust vector control application because it offers a more acceptable and graceful degradation than a complete failure.

Future work will include testing on actual hardware to study the transient disturbances caused by a fault and their effect on launch vehicle dynamics.

High redundancy electromechanical actuator concept can be extended to similar applications such as solid motor nozzle in satellite launch vehicles and primary flight control system in aircraft.

High redundancy actuators can be useful in safety critical applications involving human beings. It can also reduce the machine downtime in industrial process automation.

The jam tolerant electromechanical actuator proposed for the launch vehicle application has a unique configuration which does not require a complex fault detection isolation and reconfiguration logic in the controller. This enhances the system reliability and allows a simplex controller having a lower cost.

Teaching about families in a classroom may seem rather simple and uncomplicated because families are thought to be familiar settings – a part of our day-to-day life experience. Most often the task is not that simple. For this purpose, personal and familial biographies of students were used as part of family pedagogy for understanding the family structure and value orientations. Such an approach requires respect for students’ lived experiences as valid knowledge to use as a subjective and experiential journey to teach about families. There is a dearth of such pedagogical approaches to teach about the complexity and diversity of families in India. This chapter documents such an attempt to teach students, using three exercises, the concepts of family through experiential learning. The concepts include the myth of a normative family, nature of family change, and multigenerational extended kin relationships. The first author developed the teaching exercises and used them in the classroom. The data were collected across three consecutive MSW (Children and Families Concentration) batches of 2012–2016 from the Tata Institute of Social Sciences, Mumbai, India. A focus group interview method was used, and qualitative analysis was undertaken. The analysis of the data deconstructed the myth of the so-called normative family, helped to understand family change, and showed the presence of a range of multigenerational extended relations in families in the Indian context. The results of our study will be useful for researchers, practitioners, and teachers to employ experiential learning techniques in teaching about families in India through classroom interaction.

Concrete is a building material widely used for the infrastructural development. Cement is the binding material used for the development of concrete. It is the primary cause of CO₂ emission globally. The purpose of this study is to develop sustainable concrete material to satisfy the present need of construction sector. Geopolymer concrete (GPC) is a sustainable concrete developed without the use of cement. Therefore, investigations are being conducted to replace the cement by 100% with high calcium fly ash (FA) as binding material.

High calcium FA is used as cementitious binder, sodium hydroxide (NaOH) and sodium silicates (Na₂SiO₃) are used as alkaline liquids for developing the GPC. Mix proportions with different NaOH molarities of 4, 6, 8 and 10 M are considered to attain the appropriate mix. The method of curing adopted is ambient and oven curing. Workability, compressive strength and microstructure characteristics of GPC are analysed and presented.

An increase of NaOH in the mix decreases the workability. Compressive strength of 29 MPa is obtained for Mix-I with 8 M under ambient curing. A polynomial relationship is obtained to predict the compressive strength of GPC. Scanning electron microscope analysis is used to confirm the geo-polymerisation process in the microstructure of concrete.

This research work focuses on finding some alternative cementitious material for concrete that can replace ordinary portland cement (OPC) to overcome the CO₂ emission owing to the utilisation of cement in the construction industry. An attempt has been made to use the waste material (high calcium FA) from thermal power plant for the production of GPC. GPC concrete is the novel building material and alternative to conventional concrete. It is the ecofriendly product contributing towards the improvement of the circular economy in the construction industry. There are several factors that affect the property of GPC such as type of binder material, molarity of activator solution and curing condition. The novelty of this work lies in the approach of using locally available high calcium FA along with manufactured sand for the development of GPC. As this approach is rarely investigated, to prove the attainment of compressive strength of GPC with high calcium FA, an attempt has been made during the present investigation. Other influencing parameter which affects the strength gain has also been analysed in this paper.

This paper aims to examine the export‐led growth hypothesis for Fiji and Papua New Guinea (PNG).

The paper investigates the export‐led growth hypothesis for Fiji and PNG who have been facing dismal economic growth performances over the last couple of decades.

Findings of the study suggest that for Fiji there is evidence of export‐led growth in the long‐run, while for PNG there is evidence of export‐led growth in the short‐run.

The findings of this paper have important messages for policy makers given that export sectors in both countries investigated are underdeveloped due mainly to a sustained period of political instability.