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The purpose of this paper is to explore a new possibility of providing high-temperature stable lead-free interconnections for low-temperature co-fired ceramics (LTCC) hotplate. For gas-sensing application, a temperature range of 200°C-400°C is usually required by the sensing film to detect different gases which imply the requirement of thermally stable interconnects. To observe the effect of parameters influencing power of the device, electro-thermal simulation of LTCC hotplate is also presented. Simulated LTCC hotplate is fabricated using the LTCC technology.

The proposed task is to fabricate LTCC hotplate with interconnects through vertical access. Dedicated via-holes generated on the LTCC hotplate are used to provide the interconnections. These interconnections are based on adherence and bonding mechanism between LTCC and thick film. COMSOL software is used for finite element method (FEM) simulation of the LTCC hotplate structure.

Thermal reliability of these interconnections is tested by continuous operation of hotplate at 350°C for 175 h and cycling durability test performed at 500°C. Additionally, vibration test is also carried out for the hotplate with no damage observed in the interconnections. An optimized firing profile to reproduce these interconnections along with the experimental flowchart is presented.

Research activity includes design and fabrication of LTCC hotplate with metal to thick-film based interconnections through vertical access. Research work on interconnections based on adherence of LTCC and thick film is limited.

A new way of providing lead-free and reliable interconnections will be useful for gas sensor fabricated on LTCC substrate. The FEM results are useful for optimizing the design for developing low-power LTCC hotplate.

Adherence and bonding mechanism between LTCC and thick film can be used to provide interconnections for LTCC devices. Methodology for providing such interconnections is discussed.

Low temperature co-fired ceramics (LTCC) technology-based micro-hotplates are of immense interest owing to their ruggedness, high temperature stability and reliability. The purpose of this paper is to study the role of thermal mass of LTCC-based micro-hotplates on the power consumption and temperature for gas-sensing applications.

The LTCC micro-hotplates with different thicknesses are designed and fabricated. The role of thermal mass on power consumption and temperature of these hotplates are simulated and experimentally studied. Also, a comparison study on the performance of LTCC and alumina-based hotplates of equivalent thickness is done. A thick film-sensing layer of tin oxide is coated on LTCC micro-hotplate and demonstrated for the sensing of commercial liquefied petroleum gas.

It is found from both simulation and experimental studies that the power consumption of LTCC hotplates was decreasing with the decrease in thermal mass to attain the same temperature. Also, the LTCC hotplates are less power-consuming than alumina-based one, owing to their superior thermal characteristics (low thermal conductivity, 3.3 W/ [m-K]).

This study will be beneficial for designing hotplates based on LTCC technology with low power consumption and better stability for gas-sensing applications.

The purpose of this work is to explore the forms of intermetallic phase compounds (IMPCs) in Pt/In/Au and Pt/In/Ag joints by using isothermal solidification. This lead-free technique leads to formation of IMPCs having high-temperature stable joints for platinum-based micro-heater gas sensor fabricated on low temperature co-fired ceramic (LTCC) substrate.

Proposed task is to make an interconnection for Pt micro-heater electrode pad to the silver and gold thick-films printed on LTCC substrate. Both Pt/In/Au and Pt/In/Ag configured joints with different interactive areas prepared at 190 and 220°C to study temperature and contact surface area effects on ultimate tensile strength of the joints, for a 20 s reaction time, at 0.2 MPa applied pressure. Those delaminated joint interfaces studied under SEM, EDAX and XRD.

IMPCs identified through material analysis using diffraction analysis of XRD data are InPt3, AgIn2, AgPt, AgPt3, Au9In4 and other stoichiometric compounds. The interactive surface area between thick-films and temperature increment shows improvement in the formations of IMPCs and mechanical stability of joints. These IMPCs-based joints have improved the mechanical stability to the joints to sustain even at high operating temperatures. Elemental mapping of the weak joint contact interface shows unwanted oxide formations also reported. Physical inter-locking followed by the diffusion phenomenon on the silver substrate strengthen the interconnection has been noticed.

Inert gas environment creation inside the chamber to isolate the lead-free joint placed between heating stamp pads to avoid oxide formations at the interface while cooling which adds up to the cost of manufacturing. Most of the oxides at a joint-interface increase minute to moderate resistance with respect to the level of oxides took place. These oxides contributed heat certainly damage the micro-heater based gas sensors while functioning.

These isothermal solidification-based lead-free solder joints formation replace the existing lead-based packaging techniques. These lead-free interconnections on ceramic or LTCC substrate are reliable and durable, especially those designed to work for heavy-duty engines, even at severe environment conditions.

Platinum micro-heater-based gas sensors handles over a wide-range of temperatures about 300 to 500°C. The specific temperature level of different oxide films (SnO2) on the micro-heater is capable of detecting various specific gases. This feature of platinum based gas sensor demands durable and mechanically stable joints for continuous monitoring.

A critical analysis of packaging and sealing methods for integrated circuits, hybrid microcircuits and multichip modules has been done. The best hermetic and high yield weld seal is examined along with other conventional seals like solder seal, frit seal and plastic seal with special emphasis on materials and processes involved in each case. An overview of emerging technology is also presented. A comparative analysis is made for selection of the right technology and material for a particular requirement.

As the world economies have become more integrated and with the global economy subsequently growing, there is increasing concern regarding how such trends will affect the developing and developed nations’ trade, trade in services, gross domestic product (GDP) growth, and climate change. In fact, the relationship between globalization and the environment has become quite contentious in policy circles. In part in response to these controversies, a burgeoning amount of academic attention has emerged that examines the globalization linkage between trade and economic growth as an after effect (positive and negative). Although there have been advances in the thinking about these relationships, significant challenges still persist. In light of the above, this chapter talks about the evolution of globalization, prevailing benefits and also caters to the views of some famous economists like Stiglitz, Simon Kuznets. The crucial aspects include the review of globalization on the basis of certain parameters like Trade (as % of GDP), Trade in services (as % of GDP), per capita CO₂ emissions and per capita GDP that have impacted the trends of both developed and developing nations. It arrives at the position that many current and proposed national and multilateral environmental policies are in a possible conflict with current and proposed trade and investment rules. When climate policy and global trade rules are combined, the nature of their linkage is often a function of both domestic and international politics. This also implies that, despite the worldwide awareness of climate change, the address of climate change in trade will become increasingly significant for reducing carbon footprints.

A recent meeting involved co‐operation with the organisers of the Canadian High Technology Show and the local Chapter of the SMTA. The programme included an inspiring keynote address by Mr Frank J. Pipp, Xerox Corporation. The topic of the address was ‘Malcolm Baldridge National Quality Control and the Evaluation of Total Quality Control in Xerox Corporation.’

Low temperature co‐fired ceramics (LTCC) material is introduced as an excellent alternative to silicon, glass, or plastic materials for the fabrication of miniaturised analytical devices, though it is most widely used in the automotive and microwave industries. The paper aims to study the laser ablation of LTCC material.

This kind of green tape material is mechanised by excimer laser (KrF, 248 nm) and UV laser (Nd: YAG, 355 nm), and for the first time by infra‐red laser (1,090 nm). The optical photos and the scanning electronic microscope (SEM) photos of the LTCC ablated by different kinds of laser sources are given in this paper.

When using the UV laser, the tapered structure can be easily seen from the SEM photo. However, a kind of clear and perfect ablation of LTCC can be seen for the first time by the 1,090 nm infra‐red laser ablation.

The laser ablation of LTCC by optical fibre sources is discussed.

The case is written on the basis of published sources only.

Doodlage, a start-up incorporated in 2012 by Kriti Tula, Paras Arora and Vaibhav Kapoor, used discarded waste to create sustainable fashion products. It had a first-mover advantage in recycled fashion goods in the first 10 years of its existence. The company contributed to sustainable fashion by providing an alternative to fast fashion production, creating enormous clothing waste and environmental degradation. In the first quarter of 2022, it saved and reused 15,000 m of fabric waste. From 2018 to 2021, the company grew 150% annually, targeting the right customers and regions to expand its business. It ensured that postproduction industrial waste and postconsumption garments were used to produce clothes. It also confirmed that the waste generated in its fabric screening process was used to create stationery items and other valuable accessories.

However, the sustainable fashion model that gave the company a competitive advantage became obsolete in 2022 due to increasing competition in the industry as various players using unique ideas entered the market. The company is encountering operational and logistical challenges that are affecting its performance. The demand for its products was also subdued due to high prices of upcycled and recycled clothes and less consumer spending post-COVID pandemic. The competitors of Doodlage offered multiple products produced using environmentally friendly farming and manufacturing techniques, attracting sustainable purchasers. What should be the new portfolio of products for the company to explore future growth opportunities? Considering their vast price, can consumers be encouraged to buy upcycled clothes? How should the company ride the winds of change in the industry?

The instructor should initiate the class discussion by asking questions such as how frequently do you shop for clothes? Do you care about the fabric of your apparel? After you discard your clothes, do you think about where these goods finally end up? Data on the amount of total waste generated in the fashion industry should be communicated to students to connect it with the importance of the concept of circular economy. Post this, the instructor should introduce the business model of Doodlage to bring the discussion into the context of the fashion industry before going ahead to discuss the company’s dilemma.

1. Probabilistic calculations of cost, and profit/loss using standard probability functions

2. Decision tree to find the expected monetary value (EMV) of different options.

3. Monte Carlo simulation for risk analysis.

4. Risk analysis in project management.

Learners will be able to understand and apply the following: how to approach uncertainty in business decisions using probabilistic calculations of cost, and profit/loss using standard probability functions; how to address uncertainty in business decisions by looking forward and reasoning backward, using the decision tree technique and the EMV of different decisions; how to analyse the risk inherent in business decisions by incorporating probability distributions for all critical variables in the form of Monte Carlo simulation; and appreciation of strategic considerations in risk analysis as it applies to project management

The case describes the challenge facing Vilas Birari, the owner and chief executive of Harsh Constructions, a construction company headquartered in Nasik, India. Birari had to decide on the bid for a construction project in September of 2021, during the COVID-19 (COVID) pandemic. Due to successive waves of the pandemic, the state and federal governments announced lockdowns intermittently, causing uncertainty in costs related to labor, material and project completion. The dilemma before Birari was how to set a bid price that was not so low as to incur a loss and not so high as to lose the bid to competitors. The uncertainty made Birari’s decision-making complex. The case invites students to help Birari find an optimum bid price by using various quantitative techniques, such as Monte Carlo simulation and decision trees.

This case is intended for students of management at a master’s level, in an elective course on management science, which is often also known as decision science. This compact case can be positioned in the second half of the course, when exploring risk management using computer simulation as a tool. The case serves both as an introduction to using simulation to manage uncertainty as well a contrast with simpler methods that are covered earlier in the course.

Teaching notes are available for educators only.

CSS 7: Management Science.

This study aims to address a comprehensive and integrated investigations pertaining to the preparation of AgNPs with well-defined nano-sized scale using the aforementioned poly (meth acrylic acid [MAA])–chitosan graft copolymer, which is cheap, nontoxic, biodegradable and biocompatible agent as a substitute for the traditionally used toxic reducing agents.

AgNPs are prepared under a range of conditions, containing silver nitrate and poly (MAA)–chitosan graft copolymer concentrations, time, temperature and pH of the preparation medium. To classify AgNPs obtained under the various conditions, ultraviolet–visible spectroscopy spectra and transmission electron microscopy images are used for characterization of AgNPs instrumentally in addition to the visual color change throughout the work. The work was further extended to study the application of the so prepared AgNPs on cotton fabric to see their suitability as antibacterial agent as well as their durability after certain washing cycles.

According to the current investigation, the optimal conditions for AgNPs formation of nearly 3–15 nm in size are 5 g/l, poly (MAA)–chitosan graft copolymer and 300 ppm AgNO₃ in addition to carrying out the reaction at 60°C for 30 min at pH 12. Besides, the application of the so prepared AgNPs on cotton fabric displayed a substantial reduction in antibacterial efficiency against gram-positive and gram-negative bacteria estimated even after 10 washing cycles in comparison with untreated one.

To the best of the authors’ information, no comprehensive study of the synthesis of AgNPs using poly (MAA)–chitosan graft copolymer with a graft yield of 48% has been identified in the literature.