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This paper aims at developing an improved method, based on binary search algorithm (BSA) for the steady-state analysis of self-excited induction generators (SEIGs), which are increasingly used in wind energy electric conversion systems. The BSA is also compared with linear search algorithm (LSA) to bring out the merits of BSA over LSA.

All the parameters of SEIG, including the varying core loss of the machine, have been considered to ensure accuracy in the predetermined performance values of the set up. The nodal admittance method has been adopted to simplify the equivalent circuit of the generator and load. The logic and steps involved in the formulation of the complete procedure have been illustrated using elaborate flowcharts.

The proposed approach is validated by the experimental results, obtained on a three-phase 240 V, 5.0 A, 2.0 kW SEIG, which closely match with the corresponding predicted performance values. The analysis is shown to be easy to implement with reduced computation time.

A novel improved and simplified technique has been formulated for estimating the per unit frequency (a), magnetizing reactance (X_m) and core loss resistance (R_m) of the SEIG using the nodal admittance of its equivalent circuit. The accuracy of the predetermined performance is enhanced by considering the SEIG’s varying core loss. Only simple MATLAB programming has been used for adopting the algorithms.

This study aims to evaluate the key risk factors inherent in public–private partnership (PPP) power projects in Ghana and further determine the critical risk factors affecting both the public and private sectors in PPP power projects.

Ranking-type Delphi survey in two rounds was conducted to establish a comprehensive list of critical risk factors of PPP. Purposive and snowball sampling techniques helped obtain experts for the Delphi survey. Mean score ranking, factor analysis, Cronbach α coefficient and Kendall’s concordance were used for analysis. The probability of occurrence and severity of each risk factor were computed to obtain the risk impact.

From the list of 67 risks, 37 risk factors were deemed to be critical. The five topmost risk factors were: delay payment on contract, private investor change, political risks, fluctuating demand of power generated and public opposition. Principal component analysis grouped the risk factors into seven major themes.

This study develops an authoritative risk factor list for PPP power projects, which reflects both sector and country conditions for prioritizing and mitigating risk factors. Delphi approach adopted in this study can be used by future studies in similar environments where PPP is novel and expert respondents scarce.

Reference voltage or current generators are an important requirement for an analog or digital circuit design. Bandgap reference circuits (BGR) are most common way of generating the reference voltage. This paper aims to provide a detailed insight of design of a folded cascode operational amplifier (FC op amp) and a BGR circuit. The complete study flow from design to layout of the circuits on 180 nm semiconductor laboratory (SCL) process leading to bonding diagram for possible tape-out is discussed. This study work has been supported by MeitY, Govt. of India, through Special Manpower Development Project Chip to System Design.

This paper provides a detailed insight in design of a FC op amp and a BGR circuit. The complete study flow from design to layout of the two circuits on 180 nm SCL process leading to bonding diagram for possible tape-out is discussed. Section 2 shows the design of FC op amp, beta-multiplier circuit and their simulation results. Section 3 describes the comparison of design of conventional BGR and the proposed BGR with other state-of-art BGR circuits. Section 4 gives the comparison of their performance. The conclusion is given in Section 5.

The post-layout simulation of FC op amp show an open-loop gain of 64.5 dB, 3-dB frequency of 5.5 KHz, unity-gain bandwidth of 8.7 MHz, slew rate of 8.4 V/µs, CMRR of 111 dB and power of 25.5µW. Among the two BGR designs, the conventional BGR generated 693 mV of reference voltage with a temperature coefficient of 16 ppm/°C the other BGR, with curvature correction generated 1.3 V of reference voltage with a temperate coefficient of 6.3 ppm/°C , both results in temperature ranging from −40°C to 125°C. The chip layout of the circuits designed on 180 nm SCL process ensures design rule check (DRC), Antenna and layout versus schematic (LVS) clean with metal fill.

Slew rate, stability analysis, power are important parameters which should be taken care while designing an op amp for a BGR. Direct current gain should be kept higher to reduce offset errors. Input common mode range is decided by the operating temperature range. A higher power supply rejection ratio will reduce BGR sensitivity to supply voltage variations. Input offset should be kept low to reduce BGR error in reference voltage. However, this paper emphasis on the flow from schematic to layout using simulation tools. As part of the study, the bonding diagram for tape-out of BGR and FC design in the given SCL frame size with seal ring is also explored, for possible tape-out.

Reference voltage or current generators are an important requirement for an analog or digital circuit design. BGR are most common way of generating the reference voltage. This paper provides a detailed insight in design of a FC op amp and a BGR circuit. The complete study flow from design to layout of the circuits on 180 nm SCL process leading to bonding diagram for possible tape-out is discussed. The chip layout of the circuits was designed on 180 nm SCL process ensuring DRC, antenna and LVS clean with metal fill using Cadence virtuoso and Mentor Graphics Calibre simulation tools.

BGR are most common way of generating the reference voltage. This paper gives a detailed insight of a BGR design using a folded-cascode operational amplifier. The FC op amp is biased using a beta multiplier circuit and high-swing cascode current mirror circuit. The paper discuss FC circuit design flow from schematic to layout.

FC op amp is biased using a beta multiplier circuit and high-swing cascode current mirror. The paper discusses FC design flow from schematic to layout. The circuits were designed on 180 nm SCL technology with 1.8 V of power supply. The post-layout simulation show an open-loop gain of 64.5 dB, 3 dB frequency of 5.5 KHz, unity-gain bandwidth of 8.7 MHz, slew rate of 8.4 V/µs, CMRR of 111 dB and power of 25.5 µW. BGR were designed using FC op amp. The proposed BGR generated 1.3 V of reference voltage with a temperature coefficient of 6.3 ppm/°C in the range from −40°C to 125°C in schematic simulation.

Tanzania is rich in small hydropower (SHP) potentials. However, many of these potentials have yet to be fully used, and more than two-thirds of its rural population lacks access to electricity. The purpose of this paper is to explore the role of SHP stations in improving rural welfare in the southern highlands of Tanzania. It further explores the history, cost-effective analysis and threats to the sustainability of SHP as one of the renewable energy sources.

The study uses a qualitative research design to explore respondents’ views on the role of SHP stations in facilitating rural electrification and welfare improvement. Primary data were gathered using semi-structured interviews with the 27 key informants and beneficiaries of SHP stations from the Southern Highlands of Tanzania. In addition, the study used documentary research to complement the information from the field survey.

The findings found that SHP stations enhance rural electrification and welfare by providing electricity in remote areas with sparse populations. They operate as standalone off-grids, often by church communities and individuals. However, the sustainability of SHP stations is hampered by challenges such as climate change impacts, high capital investment costs, heavy siltation of small reservoirs, skilled manpower shortages, limited local manufacturing capabilities and infrastructural issues.

The study contributes to the ongoing debate on renewable energy supply and uses, focusing on how SHP stations could contribute to sustainable rural electrification and achieve the 2030 United Nations agenda for sustainable development, which, among other things, aims to safeguard access to sustainable and modern energy and alleviate energy poverty.

This paper aims to study passive control techniques for transonic flow over a backward-facing step (BFS) using square-lobed trailing edges. The study investigates the efficacy of upward and downward lobe patterns, different lobe widths and deflection angles on flow separation, aiming for a deeper understanding of the flow physics behind the passive flow control system.

Large Eddy Simulation and Reynolds-averaged Navier–Stokes were used to evaluate the results of the study. The research explores the impact of upward and downward patterns of lobes on flow separation through the effects of different lobe widths and deflection angles. Numerical methods are used to analyse the behaviour of transonic flow over BFS and compared it to existing experimental results.

The square-lobed trailing edges significantly enhance the reduction of mean reattachment length by up to 80%. At Ma = 0.8, the up-downward configuration demonstrates increased effectiveness in reducing the root mean square of pressure fluctuations at a proximity of 5-step height in the wake region, with a reduction of 50%, while the flat-downward configuration proves to be more efficient in reducing the root mean square of pressure fluctuations at a proximity of 1-step height in the near wake region, achieving a reduction of 71%. Furthermore, the study shows that the up-downward configuration triggers early spanwise velocity fluctuations, whereas the standalone flat-downward configuration displays less intense crosswise velocity fluctuations within the wake region.

The findings demonstrate the effectiveness of square-lobed trailing edges as passive control techniques, showing significant implications for improving efficiency, performance and safety of the design in aerospace and industrial systems.

This paper demonstrates that the square-lobed trailing edges are effective in reducing the mean reattachment length and pressure fluctuations in transonic conditions. The study evaluates the efficacy of different configurations, deflection angles and lobe widths on flow and provides insights into the flow physics of passive flow control systems.

Today's marketing is dominated by decision-making based on artificial intelligence and machine learning. This study focuses on one semi- and unsupervised machine learning technique, generative adversarial networks (GANs). GANs are a type of deep learning architecture capable of generating new data similar to the training data that were used to train it, and thus, it is designed to learn a generative model that can produce new samples. GANs have been used in multiple marketing areas, especially in creating images and video and providing customized consumer contents. Through providing a holistic picture of GANs, including its advantage, disadvantage, ethical considerations, and its current application, the study attempts to provide business some strategical orientations, including formulating strong marketing positioning, creating consumer lifetime values, and delivering desired marketing tactics in product, promotion, pricing, and distribution channel. Through using GANs, marketers will create unique experiences for consumers, build strategic focus, and gain competitive advantages. This study is an original endeavor in discussing GANs in marketing, offering fresh insights in this research topic.

The learning objectives have been prepared following Bloom’s taxonomy (Bloom et al., 1956). After completing the case study, the students will be able to identify and recall the prerequisites necessary for establishing a pathology laboratory. (knowledge); analyze the micro- and macroenvironmental factors considered by Mr Sabihul Haque in the development of the strategic plan for Healthcare Laboratories (HCL) (knowledge and application); explain the key components of the Porter’s value chain and their significance in the operation of HCL (comprehension and evaluation); use the TOWS analysis to map the internal strengths, weaknesses, opportunities and threats of HCL (application and synthesis); and analyze the challenges faced by protagonist in managing HCL and generate suggestions for addressing the challenges (analysis and synthesis).

HCL, an enterprise established in 2018 in Sahdeo Khap, Gaya, Bihar, India, aims to provide high-quality pathological diagnostic services in semi-urban and rural areas. This health-care initiative is pioneering, offering pathology services to make high-quality, low-cost diagnostic services accessible in rural India. In rural settings, numerous health-care hurdles make it challenging for individuals to access the care they need. Since its inception, HCL has expanded its reach to connect more areas, facilitating diagnostic services for people in remote regions. The establishment of laboratories in semi-urban areas aims to reduce patient travel time, costs and health risks by bringing services directly to their doorstep. Haque, the chief executive officer of the lab, grappled with multiple challenges, including selecting an appropriate location for the lab, recruiting and retaining skilled workforce, managing logistics supply, collaborating with local health-care providers, dispelling the stigma among the population that superior services are only available in cities and enhancing health literacy in rural communities. Following numerous meetings with Ms Ummati Naiyyer, head of operations, they worked collaboratively to address these challenges, developing a blueprint and future plan to operate services in rural areas. This case study provides insights into the obstacles faced by HCL striving for success in rural areas. It elucidates the beneficial application of the Porter’s value chain, along with an analysis of macro- and microenvironmental factors. Unique challenges such as societal stigma and mistrust are specifically emphasized. Students engaging with this case study will enhance their problem-solving skills through brainstorming and providing recommendations, contributing to potential solutions for HCL’s difficulties.

The teaching notes for the HCL case is designed to enhance the learning experience of undergraduate and graduate students within the context of the course. This case study serves as a valuable teaching tool, allowing students to apply theoretical knowledge to real-world scenarios in the health-care industry. The notes provide a framework for instructors to facilitate discussions, encourage critical thinking and promote a deeper understanding of key concepts related to establishing diagnostic laboratories in rural areas.

Teaching notes are available for educators only.

CSS3: Entrepreneurship.

This chapter examines the potential of solar energy for the development of sustainable tourism in Croatia. Tourism is an important economic activity in the Croatian economy due to the mild climate and many sunny days. Solar energy photovoltaic and thermal systems can help to support sustainable tourism, as well as increase employment and cooperation between local and national governments. This study compares best practices in solar energy for the Mediterranean countries of Italy, Spain, Cyprus, and Greece. The Mediterranean Basin is a strategic development area for the European Union, and solar energy will help to maintain its stability and high-quality standards of living.