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During much of 2009 and 2010, the alternative energy marketplace has been in a state of unpredictable change. The financial landscape is uncertain and profits are slim. Many companies are wondering if the journey to find alternative means for energy production is worth the investment. Wind, hydro and solar projects

During much of 2009 and 2010, the alternative energy marketplace has been in a state of unpredictable change. The financial landscape is uncertain and profits are slim. Many companies are wondering if the journey to find alternative means for energy production is worth the investment. Wind, hydro and solar projects are all struggling to make ends meet in an economic landscape that predicts success but presents challenges. Strong, lean and agile companies seem to be able to maintain a slim competitive advantage afloat, while larger, slower companies are drowning in a myriad of intricate supply chains and non-existent credit. This paper evaluates innovation opportunities for alternative energy companies, with a focus on large scale, highly integrated solar providers.

ContributorsRaica, Matt (Author) / Stebbins, Kyle (Author) / Urbanowicz, Joel (Author) / Walker, Eric H (Author)
Created2011-04-15
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In-process laser heating technique delivers a cost-efficient way to improve mechanical and geometrical properties to nearly isotropic and extremely smooth, respectively. The technique involves the incorperation of a solid-state laser into a commercial off-the-shelf 3D printer, mechanical system to allow controllable laser allumination on desired surfaces, and a gcode postprocesser

In-process laser heating technique delivers a cost-efficient way to improve mechanical and geometrical properties to nearly isotropic and extremely smooth, respectively. The technique involves the incorperation of a solid-state laser into a commercial off-the-shelf 3D printer, mechanical system to allow controllable laser allumination on desired surfaces, and a gcode postprocesser to proper control of the mechanical system. This process uses laser for local heating, to enhance mass transfer between boundaries or to enhance surface reflow to smooth surface irregularity, to improve mechanical and geometrical properties. Only less than 3 W of laser power (CO2 laser) was used for high temperature material like PEEK and Ultem; less than 1 W (808nm laser) was found to be sufficient for achieving optimal properties for PLA. This technique has the potential for after-market integration into most commercial FFF 3D printers to achieved nearly isotropic and smooth 3D printed objects with various thermoplastic polymers.

ContributorsHan, Pu (Author) / Zhang, Sihan (Author) / Hsu, Keng H. (Author)
Created2022-06-13
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Recently the domestic aviation industry has been influenced by rapidly growing ultra low-cost carriers (ULCCs). The pattern of airport markets served by ULCCs is incongruous with legacy carriers and low-cost airlines alike. Existing literature, however, is limited for North American ULCCs: research has only recently begun to identify them separately

Recently the domestic aviation industry has been influenced by rapidly growing ultra low-cost carriers (ULCCs). The pattern of airport markets served by ULCCs is incongruous with legacy carriers and low-cost airlines alike. Existing literature, however, is limited for North American ULCCs: research has only recently begun to identify them separately from mainstream low-cost carriers. This study sought to understand the market factors that influence ULCC service decisions. The relationship between ULCC operations and airport market factors was analyzed using three methods: mapping 2019 flight data for four ULCCs combined, two regression analyses to evaluate variables, and three case studies examining distinct scenarios through interviews with airport managers. Enplanement data were assembled for every domestic airport offering scheduled service in 2019. Independent variables were collected for each Part 139 airport. The first model estimated an ordinary least squares regression model to analyze ULCC enplanements. The second model estimated a binary logistic equation for presence of ULCC service. Case studies for Bellingham, Waco, and Lincoln were selected using compelling airport factors and relevant ULCC experience. Maps of ULCC enplanements revealed concentrations of operations on the East Coast. Both regression analyses showed strong relationships between population and non-ULCC enplanements (two measures of airport market size) and ULCC operations. A significant relationship also existed between tourism and enplanements. In the logit model, distance and competition variables were associated with ULCC presence. Case studies emphasized the importance of airport fees and competition in ULCC preferences, although aeronautical costs were generally not significant in the regressions.

ContributorsTaplin, Drew (Author) / Kuby, Michael (Author) / Salon, Deborah (Author) / King, David A. (Author)
Created2023-01-31
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Julius von Sachs helped establish plant physiology through his experiments in latter nineteenth-century Germany. Sachs infused the inchoate discipline of plant physiology with experimental techniques and a mechanistic stance, both of which cemented his place as one of the discipline s founders. Sachs trained a generation of plant physiologists, and

Julius von Sachs helped establish plant physiology through his experiments in latter nineteenth-century Germany. Sachs infused the inchoate discipline of plant physiology with experimental techniques and a mechanistic stance, both of which cemented his place as one of the discipline s founders. Sachs trained a generation of plant physiologists, and his stress on experimentation and mechanism influenced biologists in other disciplines, especially embryologist Jacques Loeb.

Created2010-06-07
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Petr Kropotkin proposed the theory of Pleistocene ice age, alternative theories of evolution based on embryology, and he advocated anarchist and communist social doctrines in Europe during the nineteenth and twentieth centuries. He traveled in eastern Siberia and Manchuria from 1863 until 1867, and his subsequent publications about that area's

Petr Kropotkin proposed the theory of Pleistocene ice age, alternative theories of evolution based on embryology, and he advocated anarchist and communist social doctrines in Europe during the nineteenth and twentieth centuries. He traveled in eastern Siberia and Manchuria from 1863 until 1867, and his subsequent publications about that area's geography became authoritative until the middle of the twentieth century. Kropotkin argued that his geographic and geologic observations in Asia, Finland, Sweden, and Canada, supported the theory of Pleistocene continental glaciation, often called the ice age. He was one of the first to study the ancient geography and climate of the Quaternary period, which spans from 2.5 million years ago until the present. Around the turn of the nineteenth century, Kropotkin offered what he said were complementary amendments to Charles Darwin's 1859 theory of evolution by natural selection. Kropotkin employed a variety of arguments from natural history, embryology, and geography to support his theory of mutual aid, which he argued was a positive mechanistic addition to the theory of evolution.

Created2015-06-01
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Victor Jollos studied fruit flies and microorganisms in Europe and the US, and he introduced the concept of Dauermodifikationen in the early 1900s. The concept of Dauermodifikationen refers to environmentally-induced traits that are heritable for only a limited number of generations. Some scientists interpreted the results of Jollos's work on

Victor Jollos studied fruit flies and microorganisms in Europe and the US, and he introduced the concept of Dauermodifikationen in the early 1900s. The concept of Dauermodifikationen refers to environmentally-induced traits that are heritable for only a limited number of generations. Some scientists interpreted the results of Jollos's work on Paramecium and Drosophila as
evidence for cytoplasmic inheritance. Jollos was forced to emigrate from Germany to the United States due to anti-semitic government policies in the early 1930s. Nevertheless, his work on Dauermodifikationen remained central to theoretical discourse among German zoologists concerning heredity, development, and evolution.

Created2014-09-16
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Cities in the Global South face rapid urbanization challenges and often suffer an acute lack of infrastructure and governance capacities. Smart Cities Mission, in India, launched in 2015, aims to offer a novel approach for urban renewal of 100 cities following an area‐based development approach, where the use of ICT

Cities in the Global South face rapid urbanization challenges and often suffer an acute lack of infrastructure and governance capacities. Smart Cities Mission, in India, launched in 2015, aims to offer a novel approach for urban renewal of 100 cities following an area‐based development approach, where the use of ICT and digital technologies is particularly emphasized. This article presents a critical review of the design and implementation framework of this new urban renewal program across selected case‐study cities. The article examines the claims of the so‐called “smart cities” against actual urban transformation on‐ground and evaluates how “inclusive” and “sustainable” these developments are. We quantify the scale and coverage of the smart city urban renewal projects in the cities to highlight who the program includes and excludes. The article also presents a statistical analysis of the sectoral focus and budgetary allocations of the projects under the Smart Cities Mission to find an inherent bias in these smart city initiatives in terms of which types of development they promote and the ones it ignores. The findings indicate that a predominant emphasis on digital urban renewal of selected precincts and enclaves, branded as “smart cities,” leads to deepening social polarization and gentrification. The article offers crucial urban planning lessons for designing ICT‐driven urban renewal projects, while addressing critical questions around inclusion and sustainability in smart city ventures.`

ContributorsPraharaj, Sarbeswar (Author)
Created2021-05-07
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Attitudes and habits are extremely resistant to change, but a disruption of the magnitude of the COVID-19 pandemic has the potential to bring long-term, massive societal changes. During the pandemic, people are being compelled to experience new ways of interacting, working, learning, shopping, traveling, and eating meals. Going forward, a

Attitudes and habits are extremely resistant to change, but a disruption of the magnitude of the COVID-19 pandemic has the potential to bring long-term, massive societal changes. During the pandemic, people are being compelled to experience new ways of interacting, working, learning, shopping, traveling, and eating meals. Going forward, a critical question is whether these experiences will result in changed behaviors and preferences in the long term. This paper presents initial findings on the likelihood of long-term changes in telework, daily travel, restaurant patronage, and air travel based on survey data collected from adults in the United States in Spring 2020. These data suggest that a sizable fraction of the increase in telework and decreases in both business air travel and restaurant patronage are likely here to stay. As for daily travel modes, public transit may not fully recover its pre-pandemic ridership levels, but many of our respondents are planning to bike and walk more than they used to. These data reflect the responses of a sample that is higher income and more highly educated than the US population. The response of these particular groups to the COVID-19 pandemic is perhaps especially important to understand, however, because their consumption patterns give them a large influence on many sectors of the economy.

Created2020-09-03