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Furniture longevity: how mass-produced heirloom furniture supports sustainable consumption

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In recent years, the length of time people use and keep belongings has decreased. With the acceptance of short-lived furniture and inexpensive replacements, the American mentality has shifted to thinking that discarding furniture is normal, often in the guise of

In recent years, the length of time people use and keep belongings has decreased. With the acceptance of short-lived furniture and inexpensive replacements, the American mentality has shifted to thinking that discarding furniture is normal, often in the guise of recycling. Americans are addicted to landfills. The high cost of landfill real estate and other considerable ecological impacts created by the manufacturing of furniture should persuade people to give their belongings a longer life, but in reality, furniture is often prematurely discarded. This grounded theory study takes a multi-method approach to analyze why some types of furniture are kept longer and to theorize about new ways to design and sell furniture that lasts well past its warranty. Case studies bring new insight into designer intention, manufacturer intent, the world of auction-worthy collectables and heirlooms, why there is a booming second-hand furniture market and the growing importance of informed interior designers and architects who specify or help clients choose interior furnishings. An environmental life cycle assessment compares how the length of furniture life affects environmental impacts. A product's life could continue for generations if properly maintained. Designers and manufacturers hoping to promote longevity can apply the conclusions of this report in bringing new pieces to the market that have a much longer life span. This study finds areas of opportunity that promote user attachment, anticipate future repurposing, and provide services. This thinking envisions a paradigm for furniture that can re-invent itself over multiple generations of users, and ultimately lead to a new wave of desirable heirloom furniture.

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Date Created
2011

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A theoretical analysis of microchannel flow boiling enhancement via cross-sectional expansion

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Microchannel heat sinks can possess heat transfer characteristics unavailable in conventional heat exchangers; such sinks offer compact solutions to otherwise intractable thermal management problems, notably in small-scale electronics cooling. Flow boiling in microchannels allows a very high heat transfer rate,

Microchannel heat sinks can possess heat transfer characteristics unavailable in conventional heat exchangers; such sinks offer compact solutions to otherwise intractable thermal management problems, notably in small-scale electronics cooling. Flow boiling in microchannels allows a very high heat transfer rate, but is bounded by the critical heat flux (CHF). This thesis presents a theoretical-numerical study of a method to improve the heat rejection capability of a microchannel heat sink via expansion of the channel cross-section along the flow direction. The thermodynamic quality of the refrigerant increases during flow boiling, decreasing the density of the bulk coolant as it flows. This may effect pressure fluctuations in the channels, leading to nonuniform heat transfer and local dryout in regions exceeding CHF. This undesirable phenomenon is counteracted by permitting the cross-section of the microchannel to increase along the direction of flow, allowing more volume for the vapor. Governing equations are derived from a control-volume analysis of a single heated rectangular microchannel; the cross-section is allowed to expand in width and height. The resulting differential equations are solved numerically for a variety of channel expansion profiles and numbers of channels. The refrigerant is R-134a and channel parameters are based on a physical test bed in a related experiment. Significant improvement in CHF is possible with moderate area expansion. Minimal additional manufacturing costs could yield major gains in the utility of microchannel heat sinks. An optimum expansion rate occurred in certain cases, and alterations in the channel width are, in general, more effective at improving CHF than alterations in the channel height. Modest expansion in height enables small width expansions to be very effective.

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Date Created
2011

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Assessment of global model simulations of present and future climate

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Climate change has been one of the major issues of global economic and social concerns in the past decade. To quantitatively predict global climate change, the Intergovernmental Panel on Climate Change (IPCC) of the United Nations have organized a multi-national

Climate change has been one of the major issues of global economic and social concerns in the past decade. To quantitatively predict global climate change, the Intergovernmental Panel on Climate Change (IPCC) of the United Nations have organized a multi-national effort to use global atmosphere-ocean models to project anthropogenically induced climate changes in the 21st century. The computer simulations performed with those models and archived by the Coupled Model Intercomparison Project - Phase 5 (CMIP5) form the most comprehensive quantitative basis for the prediction of global environmental changes on decadal-to-centennial time scales. While the CMIP5 archives have been widely used for policy making, the inherent biases in the models have not been systematically examined. The main objective of this study is to validate the CMIP5 simulations of the 20th century climate with observations to quantify the biases and uncertainties in state-of-the-art climate models. Specifically, this work focuses on three major features in the atmosphere: the jet streams over the North Pacific and Atlantic Oceans and the low level jet (LLJ) stream over central North America which affects the weather in the United States, and the near-surface wind field over North America which is relevant to energy applications. The errors in the model simulations of those features are systematically quantified and the uncertainties in future predictions are assessed for stakeholders to use in climate applications. Additional atmospheric model simulations are performed to determine the sources of the errors in climate models. The results reject a popular idea that the errors in the sea surface temperature due to an inaccurate ocean circulation contributes to the errors in major atmospheric jet streams.

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Date Created
2014

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Telling your stories: designing an online email based storytelling group for older adults

Description

The aim of this study is to test the feasibility of building a storytelling system for older adults to tell and share their life stories based on email. It is measured by the level of participation and people's acceptance of

The aim of this study is to test the feasibility of building a storytelling system for older adults to tell and share their life stories based on email. It is measured by the level of participation and people's acceptance of the system. The central goals were to empower people over 60 years old by providing a platform for them to share their wonderful life experience and perspectives on life and lead social services into the digital age by bridging traditional roundtable interaction and modern digital communication. A prototype was built to test the level of participation of the system and follow-up interviews were conducted in order to deeply understand people's acceptance. Content analysis was used to analyze the stories to ascertain what common themes were present. Key design considerations and key factors that affect the feasibility of storytelling system were discussed. This research expands on current research and implementation of Internet-based storytelling system and shed light on the future of combining storytelling with older adults' existing Internet knowledge. Key findings of this research are :(1) Frequency of reminiscence trigger and the number of active participants affect the level of participation collectively. Frequency is considered to be a key determinant. High frequency indicates high level of participation. (2) Categories of topics do not affect the level of participation significantly but serve as key attractions that enhance people's acceptance of the system. (3) Older adults highly accept and get involved in the new email storytelling system. This storytelling program helps them recall their memories and have a profound effect on their own introspection.

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Date Created
2014

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Understanding plasticity and fracture in aluminum alloys and their composites by 3D X-ray synchrotron tomography and microdiffraction

Description

Aluminum alloys and their composites are attractive materials for applications requiring high strength-to-weight ratios and reasonable cost. Many of these applications, such as those in the aerospace industry, undergo fatigue loading. An understanding of the microstructural damage that occurs in

Aluminum alloys and their composites are attractive materials for applications requiring high strength-to-weight ratios and reasonable cost. Many of these applications, such as those in the aerospace industry, undergo fatigue loading. An understanding of the microstructural damage that occurs in these materials is critical in assessing their fatigue resistance. Two distinct experimental studies were performed to further the understanding of fatigue damage mechanisms in aluminum alloys and their composites, specifically fracture and plasticity. Fatigue resistance of metal matrix composites (MMCs) depends on many aspects of composite microstructure. Fatigue crack growth behavior is particularly dependent on the reinforcement characteristics and matrix microstructure. The goal of this work was to obtain a fundamental understanding of fatigue crack growth behavior in SiC particle-reinforced 2080 Al alloy composites. In situ X-ray synchrotron tomography was performed on two samples at low (R=0.1) and at high (R=0.6) R-ratios. The resulting reconstructed images were used to obtain three-dimensional (3D) rendering of the particles and fatigue crack. Behaviors of the particles and crack, as well as their interaction, were analyzed and quantified. Four-dimensional (4D) visual representations were constructed to aid in the overall understanding of damage evolution. During fatigue crack growth in ductile materials, a plastic zone is created in the region surrounding the crack tip. Knowledge of the plastic zone is important for the understanding of fatigue crack formation as well as subsequent growth behavior. The goal of this work was to quantify the 3D size and shape of the plastic zone in 7075 Al alloys. X-ray synchrotron tomography and Laue microdiffraction were used to non-destructively characterize the volume surrounding a fatigue crack tip. The precise 3D crack profile was segmented from the reconstructed tomography data. Depth-resolved Laue patterns were obtained using differential-aperture X-ray structural microscopy (DAXM), from which peak-broadening characteristics were quantified. Plasticity, as determined by the broadening of diffracted peaks, was mapped in 3D. Two-dimensional (2D) maps of plasticity were directly compared to the corresponding tomography slices. A 3D representation of the plastic zone surrounding the fatigue crack was generated by superimposing the mapped plasticity on the 3D crack profile.

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Date Created
2014

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Feasibility of a negative pressure system to remove smoke from an aircraft flight deck

Description

Smoke entering a flight deck cabin has been an issue for commercial aircraft for many years. The issue for a flight crew is how to mitigate the smoke so that they can safely fly the aircraft. For this thesis, the

Smoke entering a flight deck cabin has been an issue for commercial aircraft for many years. The issue for a flight crew is how to mitigate the smoke so that they can safely fly the aircraft. For this thesis, the feasibility of having a Negative Pressure System that utilizes the cabin altitude pressure and outside altitude pressure to remove smoke from a flight deck was studied. Existing procedures for flight crews call for a descent down to a safe level for depressurizing the aircraft before taking further action. This process takes crucial time that is critical to the flight crew's ability to keep aware of the situation. This process involves a flight crews coordination and fast thinking to manually take control of the aircraft; which has become increasing more difficult due to the advancements in aircraft automation. Unfortunately this is the only accepted procedure that is used by a flight crew. Other products merely displace the smoke. This displacement is after the time it takes for the flight crew to set up the smoke displacement unit with no guarantee that a flight crew will be able to see or use all of the aircraft's controls. The Negative Pressure System will work automatically and not only use similar components already found on the aircraft, but work in conjunction with the smoke detection system and pressurization system so smoke removal can begin without having to descend down to a lower altitude. In order for this system to work correctly many factors must be taken into consideration. The size of a flight deck varies from aircraft to aircraft, therefore the ability for the system to efficiently remove smoke from an aircraft is taken into consideration. For the system to be feasible on an aircraft the cost and weight must be taken into consideration as the added fuel consumption due to weight of the system may be the limiting factor for installing such a system on commercial aircraft.

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Date Created
2013

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FE simulation based friction coefficient factors for metal forming

Description

The friction condition is an important factor in controlling the compressing process in metalforming. The friction calibration maps (FCM) are widely used in estimating friction factors between the workpiece and die. However, in standard FEA, the friction condition is defined

The friction condition is an important factor in controlling the compressing process in metalforming. The friction calibration maps (FCM) are widely used in estimating friction factors between the workpiece and die. However, in standard FEA, the friction condition is defined by friction coefficient factor (µ), while the FCM is used to a constant shear friction factors (m) to describe the friction condition. The purpose of this research is to find a method to convert the m factor to u factor, so that FEA can be used to simulate ring tests with µ. The research is carried out with FEA and Design of Experiment (DOE). FEA is used to simulate the ring compression test. A 2D quarter model is adopted as geometry model. A bilinear material model is used in nonlinear FEA. After the model is established, validation tests are conducted via the influence of Poisson's ratio on the ring compression test. It is shown that the established FEA model is valid especially if the Poisson's ratio is close to 0.5 in the setting of FEA. Material folding phenomena is present in this model, and µ factors are applied at all surfaces of the ring respectively. It is also found that the reduction ratio of the ring and the slopes of the FCM can be used to describe the deformation of the ring specimen. With the baseline FEA model, some formulas between the deformation parameters, material mechanical properties and µ factors are generated through the statistical analysis to the simulating results of the ring compression test. A method to substitute the m factor with µ factors for particular material by selecting and applying the µ factor in time sequence is found based on these formulas. By converting the m factor into µ factor, the cold forging can be simulated.

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Date Created
2013

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Retail lighting and consumer product perception: a cross-cultural study

Description

The study of lighting design has important implications for consumer behavior and is an important aspect of consideration for the retail industry. In today's global economy consumers can come from a number of cultural backgrounds. It is important to understand

The study of lighting design has important implications for consumer behavior and is an important aspect of consideration for the retail industry. In today's global economy consumers can come from a number of cultural backgrounds. It is important to understand various cultures' perceptions of lighting design in order for retailers to better understand how to use lighting as a benefit to provide consumers with a desirable shopping experience. This thesis provides insight into the effects of ambient lighting on product perception among Americans and Middle Easterners. Both cultural groups' possess significant purchasing power in the worldwide market place. This research will allow marketers, designers and consumers a better understanding of how culture may play a role in consumer perceptions and behavior Results of this study are based on data gathered from 164 surveys from individuals of American and Middle Eastern heritage. Follow up interviews were also conducted to examine the nuances of product perception and potential differences across cultures. This study, using qualitative and quantitative methods, was executed using a Sequential Explanatory Strategy. Survey data were analyzed to uncover significant correlations and relationships using measures of descriptive analysis, analysis of variance (ANOVA), and regression analysis. Interviews were analyzed using theme-based coding and reported in narrative form. The results suggest that lighting does in fact have an impact on product perception, however despite minor differences, this perception does not vary much between individuals from American and Middle Eastern cultures. It was found that lighting could affect price and quality perception with reference to store-image and store atmospherics. Additionally, lighting has a higher impact on subjective impressions of product (such as Freshness, Pleasantness, and Attractiveness), more than Price and Quality perceptions. This study suggests that particular lighting characteristics could be responsible for differences in product perception between these two cultures. This is important to note for lighting designers and marketers to create retail atmospheres that are preferable to both cultures.

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Date Created
2013

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In search of better brainstorming through a two step process

Description

Much of the literature and many of the studies surrounding brainstorming focus on the performance and the quantitative aspects of the process in comparing the efficacy of individual versus group settings, specifically the benefits and pitfalls associated with each. This

Much of the literature and many of the studies surrounding brainstorming focus on the performance and the quantitative aspects of the process in comparing the efficacy of individual versus group settings, specifically the benefits and pitfalls associated with each. This study looked at using alternate combinations of both individual and group styles of brainstorming to most efficiently maximize production of ideas and satisfaction of participants, while minimizing obstacles and shortcomings typically seen in brainstorming sessions. This research was designed to compare results of three different aspects of these sessions: real efficacy, perceived efficacy, and participant satisfaction. Two cohorts of eight student volunteers each were used to participate in and evaluate the specific session sequence they attended, either that of group then individual or individual then group. Each cohort consisted of four introverts and four extroverts, and the results and responses of each were then compared against each other in the same session and then against the results of the other session to see if there was a difference between the two personality types. The findings of this research revealed that the brainstorming session sequence of group then individual generated a larger quantity of solutions to the given problem and was perceived as more effective by both introverts and extroverts. The study also showed that introverts self-reported a higher satisfaction for the session ending in individual brainstorming, while the extroverts preferred the session ending with the group brainstorming.

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Date Created
2013

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The transformation of the modern American kitchen from 1901 through 1964: from hell on earth to the warmest room in the house

Description

Many of the scholars that have chronicled the creation of the modern American kitchen have written about how the technological, societal, and cultural revolutions of the twentieth century played a role in dramatically changing its structure and design. More recently,

Many of the scholars that have chronicled the creation of the modern American kitchen have written about how the technological, societal, and cultural revolutions of the twentieth century played a role in dramatically changing its structure and design. More recently, some scholarly research has focused on the evolution of the kitchen and its meaning over time. In several of these research publications scholars profess that the modern American kitchen, more than any other room, has come to symbolize the center or heart of the home, and the warmest room in the house. However, they are quick to acknowledge that, at the beginning of the twentieth century, the kitchen was not so fondly regarded. Little research exists regarding why individuals increasingly became attached to the kitchen or how that attachment influenced the layout, size, objects, and activities conducted in the kitchen. This thesis fills this void by exploring the implications of place attachment on the evolution of the American kitchen from 1901 through 1964. By approaching this research from a combination of design history and environmental psychology, this thesis provides a new perspective to our understanding of the evolution of kitchen design. Using this two-pronged approach, this study contributes to our understanding of the evolution of the kitchen. This study traces the evolution of the modern American kitchen using two qualitative methodologies: material culture and phenomenology. Drawing from a variety of floor plans, advertisements, and articles contained in the House Beautiful magazine 1901 through 1964, as well as writings from popular domestic advisors of the period, this thesis charts the transformation of the modern American kitchen from a "hell on earth" into the "heart and soul of the home." By combining place attachment theory and kitchen design research this thesis provides interior designers new insight into designing kitchens that foster endearing emotional attachment for our clients.

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Date Created
2013