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The consumer-products division of a multinational company is facing a decision on the sourcing of product components: whether to stay in Taiwan or switch to Mexico. See also the supplement to this case, “Cost Analysis for Sourcing Alternatives for Emerson Electric Company ACP Division” (OM-0823).

The purpose of this study is to analyze the effect of using a ceiling fan with central heating system in the winter on thermal comfort and heat transfer rate in a three-dimensional numerically.

The geometry had certain dimensions, and an occupant was modeled to be in the room. In models which were used, the flow was turbulent, and turbulence models were used for simulating turbulence. Between all the models, k-ε model had best matching.

Results show that using the ceiling fan during the winter had an efficient and considerable effect on improving the thermal comfort and energy saving inside buildings. By the use of ceiling fan, the effective room temperature has increased by 2.5°C. Furthermore, results show that by using ceiling fan in the winter, the predicted mean vote and the predicted percentage dissatisfied indexes improved. At the end, the case Room 11-0.05-15 with temperature of 87°C for radiator and normal fan velocity of o.25m/s were the optimal model that caused the complete thermal comfort and reduced energy consumption up to 28 per cent.

In the present study, the effects of using the ceiling fans on human comfort condition and heat transfer field during the winter (heating system) are studied. Following are the goals for all models: getting the appropriate temperature for radiator so that thermal comfort condition can be applied at the height of 75 cm of the room, velocity for fan so that air speed can be 0.25m/s at the height of 2 m or lower of the room and position to place the fan.

The purpose of this paper is to explore the role of locally-produced architectural design solutions for the provision of thermal comfort in the vernacular settlements of Mardin, Turkey.

With an aim of extracting clues of climate responsive design, the paper develops a socio-technical assessment methodology and presents a comparative inquiry between the vernacular and contemporary built environments of Mardin.

Findings display that the capacity of vernacular architecture in providing a more climate responsive living environment than contemporary one is in fact correlated with the design of living spaces in harmony with the local climatic conditions as well as how inhabitants traditionally use and behave in designed space.

The paper argues for a need for (re)conceptualization of thermal comfort within and through the production of housing, as well as by taking into account the ways in which end-users interact, adapt and sustain end-users' everyday life in accordance with the local climatic characteristics.

Success and business reputation depend upon the quality of products where product quality depends upon the capability of a process, yield value and sigma score, etc. Poor quality of ceiling fan and mass rejection from quality check resulted in an alarming amount of cost for rework. As a result, the fulfillment of the production target was getting difficult day by day. The main purpose of this research is to identify the crucial causes for humming noise of ceiling fans and control it to a tolerable level so that maximum quality can be achieved.

The poor quality of ceiling fans was determined from the Pareto analysis of the define, measure, analyze, improve and control model which was humming noise during running and further actions were undertaken regarding the reduction of the humming noise. Project charter was formed before initiating the measure phase to study the suppliers, inputs, processes, outputs and customers diagram with process parameters and existing noise data were collected from random samples to determine the rolled throughput yield (94.95% existing) and existing sigma score which value of 3.14 and also the poor value (1.05) of process potential index implied that the process condition was below standard (<1.33) and need to be improved badly. Then root causes analysis and relationship diagram was prepared to identify the possible causes and with the design of experiments and correlation analysis, it was clear that the air gap between the stator and rotor was the main culprit behind the humming noise.

The minimum value of air gap was determined from boxplot analysis which was 0.2 mm–0.225 mm and the corresponding mean, the minimum and maximum value of sound level in dB (37.5–40.3 dB) for 0.225 mm air gap with the watt consumption (83 w) from the hypothesis test for the corresponding air gap. Finally, the updated sigma score and process capability analysis were performed with control charts to show the comparison after applying the DMAIC-six sigma methodology. The final sigma score was 5.1 which indicates a significant improvement of the process with the capability of saving US$23,438/year caused by the poor quality of ceiling fans.

Only quantitative values of the causes behind the humming noise were possible to identify. Other trivial many causes elimination might improve the sigma score closer to 6.00. The final sigma score that was achieved from this research was sustainable.

A structural approach with proper data analysis and application of various tools to detect the actual cause behind the humming noise of ceiling fans with numerical value has not been found in any literature. This research study can be a valuable asset for ceiling fan mass producers.

In this chapter, inventory and sales data from a small business with seven showrooms are evaluated to forecast future sales and maximize total profits. In each showroom, three major brands of ceiling fans are sold and a limited amount of products from each brand are displayed. Each showroom varies in their sales volume, display capacity, and profit margins. Using historical data, the optimal display configuration was determined for each showroom; that is, the proportion of products from each brand to display in the limited display grid, while acknowledging existing constraints. Next using the optimal displays, profit for the next year is forecasted. Finally a comparison is made between actual and forecasted results and profits pre and post the optimal product display.

Air permeability of ceiling linings is an important element in understanding air and moisture flux from living spaces into the roof cavity. Ideally, these two spaces are decoupled to avoid transportation of moist indoor air into the attic space, where it can lead to condensation on the cold roof cladding. The purpose of this paper is to experimentally characterise the air permeability of a variety of common ceiling types. The results are given as leakage functions. Characteristic leakage data are also given for several ceiling penetrations. A case study illustrates the relevance of these data.

A specially designed test facility allows the installation of different ceiling types of up to 38 m² in area. Laminar flow elements are used to measure the volumetric flow across the ceiling while recording the pressure difference. The experimental data are fitted to the leakage function equation Q =c (ΔP)ⁿ. Ceiling penetrations are characterised in a similar way. For the case studies estimating the transport of moisture into the roof cavity, indoor climate data have been obtained using humidity and temperature sensors.

Air leakage functions are given for a number of common ceiling linings and ceiling penetrations. These data can be used in simulations aimed at modelling moisture flux into the roof cavities. In the case study, the authors also give indoor climate data of residential dwellings in New Zealand.

This paper addresses the need for robust ceiling air permeability data in whole-house temperature and moisture transport simulations.

The case discussion begins with an understanding of Davis’s three-circle model. It then leads toward the key resources and challenges, by system and development stage as given by Gersick et al. (1997). After understanding the family business system, the case delves into making the students understand the circumplex model of the marital and family system. This matrix talks about the flexibility in the business structure along with cohesion in the family unit. The case then gets into the discussion about succession and the new generation joining the family business and the conflicts that may arise due to the same. It might be imperative to bring out the different forms of conflict that may arise in the family and business system. Researchers have identified three forms of conflict – task, process and relationship (Mckee, Madden, Kellermans and Eddleston, 2014). As passing the baton would take place next for this business in the case, the current generation needs to look at the future growth strategy for the business. Here, the discussion refers to the exploitation and exploration matrix given by Bergfeld and Weber (2011).

This is a primary data case. The data has been collected from SK Enterprises. Interviews were conducted to arrive at the issues and challenges discussed in the case.

This case talks about the dilemma of a first-generation entrepreneur. Jatinder Agarwal was the owner of SK Enterprises, a light-engineering firm manufacturing bright bars, engine parts and ceiling fan shafts. He had set up the business in 1984. His brother, Ramesh was helping him in the business. The business had prospered and grown from a single product manufacturing workshop in 1984 to two factories manufacturing multiple light engineering products. In 2015, the business was doing well and both Jatinder and Ramesh were excited to involve their respective sons, Pranav and Sanidh in the business after completion of their education. The case is about the challenges faced by Jatinder and Ramesh with the entry of a new generation. Jatinder and Ramesh were working in the family business with an implied structure where the business was a sole proprietorship in the name of Jatinder but the decisions were taken by both the brothers collectively. With the entry of the new generation, Jatinder had to decide how to re-organize the business and avoid conflicts in the family. He also had to take a decision regarding the future course of strategy, which would help the business grow further.

This case is about the dilemmas faced by a first-generation entrepreneur. The case can be taught in an “entrepreneurship” course, in a post-graduate MBA program. This case can also be taught in a family business program as part of the course on “Understanding Family Business – Managing Paradoxes” or “Building Lasting Family Business – Synergy in Vision, Values and Strategy.” This case can also be taught as part of a “business strategy” or “human resource management” in MBA or executive MBA program in the first year.

To preserve both cultural collections and historical buildings that house them, a technologically simple yet robust climate control system was installed in the Historic Archive of the Canary Islands. The archive is located in a municipal building, a late nineteenth century massive masonry building in the city of La Laguna, on Tenerife Island, Spain. The system was designed to maintain the RH level necessary for preventing microbial activities on collections in cultural institutions, by operating residential‐type ventilators and a convective heater under a humidistatic control. We have confirmed that the system not only successfully eliminated events of high relative humidity but also stabilized the climate. The annual temperature variation was significantly reduced, although daily variations increased. The room's moisture content was reduced to less than that of the outside, and microbial activities were reduced in the environment. The system was simple to install and inexpensive to operate.

The purpose of this study was to examine how data from the World Health Organization, United States Environmental Protection Agency and Center for Disease Control have evolved with relation to engineering controls for heating, ventilation and air-conditioning (HVAC) systems to mitigate the spread of spread of aerosols (specifically related to the COVID-19 pandemic) in occupied buildings.

A document analysis of the pandemic-focused position documents from the aforementioned public health agencies and national HVAC authorities was performed. This review targeted a range of evidence from recommendations, best practices, codes and regulations and peer-reviewed publications and evaluated how they cumulatively evolved over time. Data was compared between 2020 and 2021.

This research found that core information provided early in the pandemic (i.e. early 2020) for engineering controls in building HVAC systems did not vary greatly as knowledge of the pandemic evolved (i.e. in June of 2021). This indicates that regulating agencies had a good, early understanding of how airborne viruses spread through building ventilation systems. The largest evolution in knowledge came from the broader acceptance of building ventilation as a transmission route and the increase in publications and ease of access to the information for the general public over time.

The promotion of the proposed controls for ventilation in buildings, as outlined in this paper, is another step toward reducing the spread of COVID-19 and future aerosol spread viruses by means of ventilation.