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Asexual queen succession (AQS) species produce queens via thelytokous parthenogenesis, which significantly impacts their social life history. For the first time, we discovered that Reticulitermes aculabialis exhibits the phenomenon of parthenogenesis under experimental conditions, and we also investigated the genetic structure of wild colonies of this species using polymorphic microsatellite loci. Our genetic analysis revealed that 93.2% of the secondary queens in the wild colonies were homozygous at all loci, indicating parthenogenesis in these secondary queens, while workers (2.5%), soldiers (0%), nymphs (0%), and alates (6.7%) had low rates. Genetic analysis revealed that the mean number of alleles per group (Na) ranged from 2.000 ± 0.000 to 2.500 ± 0.428, with 83.3% polymorphic loci (PPL). The observed heterozygosity (Ho) varied from 0.467 ± 0.141 to 0.583 ± 0.098, indicating significant genetic diversity among workers and soldiers. In contrast, soldiers and nymph develop predominantly through sexual reproduction than alates and workers. The occurrence of AQS in R. aculabialis suggests a different mechanism of ploidy restoration, highlighting the diversity of reproductive mechanisms across various lineages of the Termitidae and non-Termitidae termites.

Hepatitis E virus (HEV) is a major cause of acute jaundice in South Asia. Gaps in our understanding of transmission are driven by non-specific symptoms and scarcity of diagnostics, impeding rational control strategies. In this context, serological data can provide important proxy measures of infection. We enrolled a population-representative serological cohort of 2,337 individuals in Sitakunda, Bangladesh. We estimated the annual risks of HEV infection and seroreversion both using serostatus changes between paired serum samples collected 9 months apart, and by fitting catalytic models to the age-stratified cross-sectional seroprevalence. At baseline, 15% (95 CI: 14–17%) of people were seropositive, with seroprevalence highest in the relatively urban south. During the study, 27 individuals seroreverted (annual seroreversion risk: 15%, 95 CI: 10–21%), and 38 seroconverted (annual infection risk: 3%, 95CI: 2–5%). Relying on cross-sectional seroprevalence data alone, and ignoring seroreversion, underestimated the annual infection risk five-fold (0.6%, 95 CrI: 0.5–0.6%). When we accounted for the observed seroreversion in a reversible catalytic model, infection risk was more consistent with measured seroincidence. Our results quantify HEV infection risk in Sitakunda and highlight the importance of accounting for seroreversion when estimating infection incidence from cross-sectional seroprevalence data.

This paper presents a novel decoupling technique for two-element multiple-in multiple-out (MIMO) antennas for smartwatch applications with floating metallic bezel. The radiating elements consist of embedded loop-type ground-radiation antennas and operate at the 2.45 GHz Bluetooth/Wi-Fi bands. An isolator, consisting of a loop-type structure with a lumped capacitor, is attached externally to the ground plane such that wideband isolation between the antennas has been achieved. It is demonstrated that the small-sized isolator is coupled with the large-sized bezel surrounding the ground plane, where the bezel operates as a low-Q decoupler between the antenna elements producing wideband isolation property. Accordingly, optimized results can be obtained by controlling the location of the isolator, the gap between the isolator and the bezel, and the loaded capacitor. Simulation and measured results have been presented to validate the design performance. The measured −10 dB impedance bandwidth of both antenna elements is more than 210 MHz, whereas the isolation bandwidth is 770 MHz with reference to 20 dB. The envelop correlation coefficient is <0.1 in the operating band. Furthermore, the proposed technique is versatile regardless of the angular separation of the antenna elements on the circular ground plane, which makes it a good candidate for smartwatch MIMO applications in practical scenarios.

Objective:

We estimated the cost-effectiveness of home fortification with micronutrient powder delivered in a sales-based programme in reducing the prevalence of Fe deficiency anaemia among children 6–59 months in Bangladesh.

Design:

Cross-sectional interviews with local and central-level programme staff and document reviews were conducted. Using an activity-based costing approach, we estimated start-up and implementation costs of the programme. The incremental cost per anaemia case averted and disability-adjusted life years (DALY) averted were estimated by comparing the home fortification programme and no intervention scenarios.

Setting:

The home fortification programme was implemented in 164 upazilas (sub-districts) in Bangladesh.

Participants:

Caregivers of child 6–59 months and BRAC staff members including community health workers were the participants for this study.

Results:

The home fortification programme had an estimated total start-up cost of 35·46 million BDT (456 thousand USD) and implementation cost of 1111·63 million BDT (14·12 million USD). The incremental cost per Fe deficiency anaemia case averted and per DALY averted was estimated to be 1749 BDT (22·2 USD) and 12 558 BDT (159·3 USD), respectively. Considering per capita gross domestic product (1516·5 USD) as the cost-effectiveness threshold, the home fortification programme was highly cost-effective. The programme coverage and costs for nutritional counselling of the beneficiary were influential parameters for cost per DALY averted in the one-way sensitivity analysis.

Conclusions:

The market-based home fortification programme was a highly cost-effective mechanism for delivering micronutrients to a large number of children in Bangladesh. The policymakers should consider funding and sustaining large-scale sales-based micronutrient home fortification efforts assuming the clear population-level need and potential to benefit persists.

The scholarship on political skill documents that it is a social savvy, personal style construct, associated with positive personal and organizational outcomes. However, this study takes a counterintuitive view and demonstrates that despite being a positive resource, political skill also has the potential to be used as a self-serving device to achieve one's personal agendas in the form of self-serving counterproductive work behaviors. Borrowing insights from the trait activation theory, this study demonstrates that a context, high in political perceptions, acts as an incentivized condition for politically skilled people to execute its dark side. The results supported the hypothesis and revealed that under high perceptions of organizational politics, political skill will have a significant, positive relation with self-serving counterproductive work behaviors. The study discusses important theoretical and practical implications of these results and extends the domains of political skill and counterproductive work behaviors.

This comprehensive and self-contained textbook will help students in acquiring an understanding of fundamental concepts and applications of engineering mechanics. With basic prior knowledge, the readers are guided through important concepts of engineering mechanics such as free body diagrams, principles of the transmissibility of forces, Coulomb's law of friction, analysis of forces in members of truss and rectilinear motion in horizontal direction. Important theorems including Lami's theorem, Varignon's theorem, parallel axis theorem and perpendicular axis theorem are discussed in a step-by-step manner for better clarity. Applications of ladder friction, wedge friction, screw friction and belt friction are discussed in detail. The textbook is primarily written for undergraduate engineering students in India. Numerous theoretical questions, unsolved numerical problems and solved problems are included throughout the text to develop a clear understanding of the key principles of engineering mechanics. This text is the ideal resource for first year engineering undergraduates taking an introductory, single-semester course in engineering mechanics.

Covering detailed discussion of fundamental concepts of economics, the textbook commences with comprehensive explanation of theory of consumer behavior, utility maximization and optimal choice, profit function, cost minimization and cost function. The textbook covers methods including present worth method, future worth method, annual worth method, internal rate of return method, explicit re-investment rate of return method and payout method useful for studying economic studies. A chapter on value engineering discusses important topics such as function analysis systems techniques, the value index, value measurement techniques, innovative phase and constraints analysis in depth. It facilitates the understanding of the concepts through illustrations and solved problems. This text is the ideal resource for Indian undergraduate engineering students in the fields of mechanical engineering, computer science and engineering and electronics engineering for a course on engineering economics/engineering economy.

Summary

ABOUT ENGINEERING ECONOMICS WITH APPLICATIONS

Engineers are required to provide economically feasible solutions to existing problems. To achieve this, engineers must possess knowledge of economy to evaluate the monetary consequences of the products, projects and processes that they design. Engineering design solutions do not exist in a vacuum but within the context of a business opportunity. Since almost every problem has multiple solutions, so the issue is: how does one rationally select a design with the most favorable economic result? The answer to this question is provided by engineering economy. Engineering economy, the analysis of the economic consequences of engineering decisions, is said to have originated in A. M. Wellington's The Economic Theory of Railway Location, published in 1887. Engineering economy is now considered a part of the education of every engineer, as it provides a systematic framework for evaluating the economic aspects of competing design solutions. Just as engineers model the effect of temperature on cutting tools or the thermodynamic response of an air compressor, they must also model the economic impact of their recommendations. What is ‘engineering economy’ and why is it so important? The initial reaction of many engineering students to this question is, ‘money matters will be handled by someone else and I need not worry about these matters’. In reality, any engineering project must be, not only physically realizable but also economically affordable. Understanding and applying economic principles to engineering have never been more important. Engineering is more than a problem-solving activity focusing on the development of products, systems, and processes to satisfy a need or demand. Beyond function and performance, solutions must also be economically viable. Design decisions affect limited resources such as time, material, labor, capital and natural resources, not only initially i.e. during conceptual design but also through the remaining phases of the life cycle i.e. during detailed design, manufacture and distribution, service, retirement and disposal. Engineers should realize that the solution provided by them does not make sense and will not be acceptable, if it is not profitable.

Summary

INTRODUCTION

Engineering or business projects require huge capital investments. Economy studies are necessary to be conducted to establish whether a proposed capital investment and its associated expenditures can be recovered over time in addition to a return on the capital that is attractive in view of risks involved and opportunity costs of the limited funds. The concepts of interest and money-time relationships of Chapter 4 are quite useful in arriving at the investment decision.

Since different projects involve different patterns of capital investment, revenue or savings cash flows and expenditure or disbursement cash flows, no single method is perfect for making economy studies of all types of projects. As a result, several methods for making economy studies are commonly used in practice. All methods will produce equally satisfactory results and will lead to the same decision, provided the inherent assumptions of each method are enforced.

This chapter explains the working mechanism of six basic methods for making economy studies and also describes the assumptions and interrelationships of these methods. In making economy studies of the proposed project, the appropriate interest rate to be used for discounting purpose is taken to be equal to the minimum attractive rate of return (M.A.R.R.) expected by the fund provider. The value of M.A.R.R. is established in view of the opportunity cost of capital which reflects the return forgone as it is invested in one particular project.

BASIC METHODS

The following six methods are commonly used for making economy studies:

Equivalent worth:

Summary

INTRODUCTION

To thrive in today's competitive markets, organizations are looking for smart ways of doing business and work. They cannot afford extensive time delays and increased costs. Value Engineering (VE) is a methodology developed to assist individuals as well as enterprises that will allow them to make changes to augment their processes or services. Several establishments discovered that the methods being followed in the past were insufficient and, therefore, it was essential for them to bring changes to their working style. Using the VE practices, small changes along with hard work and common sense can improve things for organization.

CONCEPT OF VALUE ENGINEERING

Larry Miles, a procurement engineer for General Electric, introduced the VE methodology during World War II. The problem he was facing was that he was not able to obtain material to manufacture the turbo-supercharger for the B-17 and P-47 airplanes. He developed a technique which did not solve the problem of procuring the material, but addressed the functionality of each material. The group determined the functionality of every component in the turbo-supercharger. Then they established the more economical constituents to attain the desired function.

VE can be defined as a systematized or methodical tactic, focused on analyzing the functionality of systems, apparatus, amenities, services and supplies with the objective of realizing their necessary functionality at the lowermost life-cycle cost, without affecting requisite capability, consistency, eminence and safety. Since more than seven decades, many organizations have been using, analyzing and refining the VE procedures. The basic aspect of VE is that it makes you acquire the ability to think in different ways. The basic features of VE are shown in Fig. 13.1.

Value is the goal, not the cost. Sometimes the highest price items have the best value. Delivering value to the customer is the aim of the organization. Some people think that making things better means reducing the cost of the product and, in that process, sometimes the functionality of the item is reduced, which reduces the value. However, this is incorrect. VE is not against reducing cost, but not at the cost of reducing the functionality or value of the product. VE also emphasizes on cost reduction, but without reducing the functionality.

Generally, VE is achieved with the help of multidisciplinary teams. Earlier, organizations succeeded by giving a problem or a question to an individual.

Summary

INTRODUCTION

The projects that are owned, used and financed by the government (and hence the citizens) are classified as public sector projects. The primary purpose of such projects is to provide services to the people at no profit. Examples of projects related to public sector include hospitals and clinics, educational institutions, transportation, police and fire service, public housing, postal services, etc. It has been observed that such projects often require large initial investments, possibly distributed over several years. Public sector projects do not yield direct profit, but they require huge investments that are paid by the appropriate government unit. The successful implementation of the public sector projects provides benefits to the citizens. It is found that certain undesirable consequences, for example impact on environment, are often associated with the public sector projects. Therefore, the economic analysis of such projects must not only consider these negative consequences but also should quantify them with great accuracy. To perform an economic analysis of public sector projects, the costs (initial and annual), the benefits, and the disbenefits, if considered, must be estimated as accurately as possible in monetary units.

Costs refer to the estimated expenditures to the government body for construction, operation and maintenance of the project, less any expected salvage value.

Benefits refer to the advantages expected by the owners, i.e., the public.

Disbenefits refer to any expected undesirable consequences to the owners if the project is implemented.

Economic analysis of public sector projects is different from those of private sector projects. For public sector projects, the initial costs are usually large, the expected life is long and the sources for capital are usually a combination of taxes levied on the citizens, user fees, bond issues and private lenders. It is very difficult to make accurate estimates of benefits and disbenefits for a public sector project. The interest rates for the public sector are lower than those for private sector. The methods that are used to perform economic analysis of public sector projects are discussed in the following sections.

BENEFIT/COST ANALYSIS OF A SINGLE PROJECT

The benefit/cost (B/C) ratio is a fundamental analysis method for public sector projects. In this method, all costs and benefits estimates are converted to a common equivalent monetary unit (P.W., A.W., or F.W.) at the given interest rate.

Summary

INTRODUCTION

Depreciation is defined as decrease in the value of a physical property or asset with the passage of time. A physical asset has value because it provides monetary benefits to its owner. These benefits are in the form of future cash flows resulting from (i) the use of the asset to produce saleable goods or services, or (ii) the ultimate sale of the asset at the end of its useful life. Depreciation, thus, represents decrease in the value due to lessening in the ability to produce these future cash flows, as a result of several causes such as wear and tear and obsolescence.

Although, depreciation does occur, it is really difficult to determine its magnitude well in advance. Depreciation is not an actual cash flow but it is a tax-allowed deduction included in tax calculations in almost all industrialized countries. Depreciation lowers income tax as per the relation:

Tax = (income – deductions) (Tax rate)

DEPRECIATION TERMINOLOGY

The definitions of the terms that are used in calculation are given below:

Book Depreciation Book depreciation is used by a corporation or business firm for internal financial accounting. It indicates the reduced investment in an asset based upon the usage pattern and expected useful life of the asset.

Tax Depreciation This is used in tax calculations as per government regulations. A company subtracts an annual tax of depreciation from its annual income to calculate the amount of taxes due each year. However, the tax depreciation amount must be calculated using a government approved method.

First Cost or Unadjusted Basis This represents the installed cost of the asset. It includes purchase price, delivery and installation fees, and other depreciable direct costs incurred to prepare the asset for use. The term unadjusted basis, B or simply basis, is used when the asset is new, whereas the term adjusted basis is used after some depreciation has been charged.

Book value This represents the remaining, un-depreciated capital investment on the books or record of the company after the total amount of depreciation charges to date have been subtracted from the basis. The book value, BVt is usually determined at the end of each year.

Recovery period This represents the depreciable life n of the asset in years.

Summary

INTRODUCTION

Every business organization engaged in the manufacturing of tangible products faces the problem to decide whether it is more advantageous to make a particular item in-house, or to buy it from a supplier. The choice involves aspects which are both qualitative such as quality control, and quantitative such as the relative cost factors. In order to decide whether to make or buy a product, the company generally analyzes the capacity of its facilities and the cost at which the product can be bought. Subsequently, the option that involves the least cost is selected by the company. Buying option often appears to be feasible and beneficial for a company which manufactures low volumes of product. In situations where the total cost of buying a product is more than or equal to the total cost of making it, it is recommended to make the product within the company.

FEASIBLE ALTERNATIVES FOR LAUNCHING NEW PRODUCTS

It is a natural tendency of a business organization to thrive and grow in order to earn higher profits. Some of the most efficient ways in which this can be done include (i) backward integration and (ii) forward integration. In both these approaches new product(s) is introduced by the organization. To implement its new preposition, the company may adopt any one of the following strategies:

Summary

INTRODUCTION

A project consists of a set of activities that are interrelated in a logical sequence and they need to be executed in a certain order for timely completion of the project. Most realistic projects undertaken by organizations such as Infosys, Honda Motors, or the Indian Defense Department, etc., are large and complex. Delhi Development Authority (DDA) building residential houses, for example, must complete thousands of activities costing crores of rupees. Indian Space Research Organization (ISRO) must inspect countless components before it launches a satellite. Almost every industry worries about how to manage similar large scale, complicated projects effectively. It is a difficult problem, and the stakes are high. Crores of rupees in cost overruns have been wasted due to poor planning of projects. Unnecessary delays have occurred due to poor scheduling. How can such problems be solved? The tools and techniques of Project Management (PM) can provide a solution to such problems. PM is concerned with planning, scheduling, monitoring and control of the projects. It aims at timely and cost effective completion of the projects and, to achieve this objective, it performs functions in phases which are discussed in the next section.

PHASES OF PROJECT MANAGEMENT

Effective management of a project requires appropriate actions to be taken by the management at different stages of the project, from its planning to completion. Thus, project management involves the following phases:

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Asexual queen succession in the subterranean termite Reticulitermes aculabialis Tsai et Hwang (Blattodea: Heterotermitidae)

Annual risk of hepatitis E virus infection and seroreversion: Insights from a serological cohort in Sitakunda, Bangladesh

A wideband decoupling method using bezel-coupled loop-type isolator for smartwatch MIMO applications

Cost-effectiveness of a market-based home fortification of food with micronutrient powder programme in Bangladesh

Political skill and self-serving counterproductive work behaviors: Moderating role of perceptions of organizational politics

Engineering Mechanics

Principles of Engineering Economics with Applications

Preface

Summary

5 - Methods for Making Economy Studies

Summary

Dedication

Index

13 - Value Engineering

Summary

9 - Economic Evaluation of Public Sector Projects

Summary

Contents

10 - Economics Study Considering Inflation

Appendix C

8 - Depreciation

Summary

Bibliography

11 - Make or Buy Decision

Summary

12 - Project Management

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Engineering Mechanics

Principles of Engineering Economics with Applications

Summary

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