1,365,494 research outputs found
Dedicatòria de Juan Lechner a José Agustín Goytisolo
No full textCon la estima y la amistad de Juan Lechner. 1/XII/75
Lechner Air Mining Machine
No full textAir-powered mining machine invented by Francis M. Lechner of Columbus, Ohio in 1876. It was designed to mechanically under-cut coal. The Lechner Mining Machine Company, which became the Jeffrey Manufacturing Company in 1887, manufactured the machine
Understanding industry emergence through entrepreneurship from a social movement perspective
No full textIndustry emergence is a complex phenomenon. The entrepreneurship literature has been characterized by individualistic explanations (‘hero’ entrepreneurs), complemented by institutional approaches. Sociology studies can offer alternative explanations for industry emergence. We draw from the concepts of Social Movements to frame the process of industry emergence in its initial phase. We synthesize the theoretical research on social movements, entrepreneurship, and industry emergence in an effort to develop a conceptual framework to improve our understanding of the pre-emergence of an industry. Our main contribution lies in understanding entrepreneurship, and thus industry emergence, as a community process in which multiple actors eventually result in a reduced number of early start-ups, which gives rise to a new industry. In addition, we propose that the type of movement will lead to different enablers and barriers to industry emergence
From invention to industry from a social movement perspective: the emergence of the 3D printing industry
No full textIn the entrepreneurship literature, the phenomenon of industry emergence has been largely investigated from an institutional perspective. Appropriate institutions would allow then a group of individual entrepreneurs (“the heroes”) to create an industry through innovative ventures. New ventures create new industries and firm entry, survival, and exit drive industry evolution. Our research, however, explores what creates the favorable set of circumstances for new ventures to emerge and focuses on the pre-emergence phase and we propose that the patterns of emergence resemble those of social movements. Through an actor perspective, this research highlights the existence of diverse actors, not necessarily entrepreneurs, who are necessary to trigger a collective action during the pre-emergence phase of industries. This research is also distinct from entrepreneurial ecosystems as its development already requires some successful entrepreneurial action. The 3D printing industry was chosen as a single longitudinal case study, where the actors are the embedded units of analysis. The findings of the study lead to the identification of three aggregate dimensions—“Social Movement Composition,” Temporal Engagement,” and “Coalitions Development”—that were prevalent during the pre-emergence phase of the 3D printing industry. Our propositions emphasize the importance of large collective action and the role of multiple actors in order to create the conditions for, first, firm emergence and, the second, to the process of industry emergence
Dr. John R. Lechner speech about the disloyalty of the Japanese and the threat they pose to the nation, July 12, 1942
No full textLechner was a vocal advocate for the eviction of the Japanese following the attack on Pearl Harbor. In his speech, Lechner argues that the Japanese are waging a campaign of destruction and not even Japanese-American citizens can be trusted. According to Lechner "An American woman who was with the Red Cross Unit when Pearl Harbor was attacked saw the school seals on the fingers of dead Japanese pilots showing that they had attended school in California and Hawaii, the students knew ever foot of Pearl Harbor. A Doctor Lee ? a highly intellectual man, just arrived in the U.S. Says that 50% of Honolulu are Japanese, no restrictions being placed on them. The Japanese there say they are loyal to the U.S. but one of their papers came out with the statement by a naval officer from Japan to the effect that Japan would bring the U.S. to its knees."After Japan attacked Pearl Harbor on December 7, 1941, the United States government began enacting a series of measures against those with Japanese ancestry. On February 19, 1942, President Franklin Roosevelt issued Executive Order 9066, authorizing military commanders to designate "military areas" at their discretion, "from which any or all persons may be excluded." On March 2, 1942, General John DeWitt signed Public Proclamation No. 1 establishing the Pacific coast and 100 miles inland as Military Area No. 1 and requiring that anyone with "enemy" ancestry evacuate
Lechner Air Mining Machine photograph
No full textThe 1877 model of the Lechner air mining machine revolutionized the coal mining industry. This image measures 8.5" by 11" (21.59 by 27.94 cm). In the 1870s, coal mining was slow and dangerous work. In a typical 12-hour day, productivity was only two tons per man. Much of the labor involved under-cutting--a miner had to lie on his side while digging a 6-inch-thick cut 4 feet deep across a 10-to-20-foot wide face. In 1876, a Columbus man, Francis Lechner, designed a chain-driven, air-powered machine that could undercut the coal mechanically, increasing daily productivity by one ton of coal per man. Lechner teamed up with Joseph Andrew Jeffrey and formed the Lechner Mining Machine Company in 1877. The Lechner coal-cutting machine eventually became a standard for the coal industry. The Columbus-based business, which in 1887 became known as the Jeffrey Manufacturing Company, was one of the city's most successful and long-lasting firms of the 20th century
Y-Rail - a Novel Ultralight, High-Capacity APM
No full textY-Rail is an innovative, ultra-light APM based on small, individually controlled cars. It is suited for a variety of transit services, including conventional line-haul as well as individual origin to destination services know from PRT systems. However, its bigger size and more robust transport concept makes Y-Rail suitable for high peak-load transportation tasks. Y-Railmay therefore be classified as high-performance, ultralight GRT (Group Rapid Transit) /1/ system. The new system is primarily conceived to offer transport solutions for local centers such as airports, railway stations, shopping-malls or exhibition grounds, that need to be mutually connected to parking areas and other transportation facilities. As a second application area, Y-Rail offers affordable perspectives for environment-friendly and efficient mass transportation solutions to small and medium-sized cities as well as peripheral suburbs. A new technical concept provides considerable savings in investment, high peak-load capability as well as economic, demand-oriented 24h and taxi-alike services. Y-Rail's ultra-light guideway with minimized shadow cast can easily be integrated in buildings or conducted at ground level, elevated or in tunnels. With these features, Y-Rail has the potential to become a well-accepted urban transport solution as trams and buses are today
DUALITY IN SUPERGRAVITY THEORIES
No full textThe target space dynamics of supermembrane (and superstring) theories is described by supergravity theories. Supergravity theories associated to dual supermembrane theories live in the same space-time dimension and are themselves dual to each other. We present a unified treatment in superspace of the two dual formulations of D = 10, N = 1 pure supergravity based on a strictly super-geometrical framework: the only fundamental objects are the super Riemann curvature and torsion, and the related Bianchi identities are sufficient to set the theory on shell; there is no need to introduce, from the beginning, closed three-or seven-superforms. This formulation extends also to non-minimal models. Moreover, in this framework the algebraic analogy between pure super Yang-Mills theoriesand pure supergravity in D = 10 is manifest. As an additional outcome in the present formulation the supersymmetric partner of the ABBJ-Lorentz anomaly in pure D = 10 supergravity can be computed in complete analog..
The competitiveness of entrepreneurial firms from a network perspective
No full textThis book sheds light on how the competitiveness of entrepreneurial firms can be understood from a relational perspective. The relational perspective complements internally focused approaches to explain firm competitiveness. Through the review of publications of the author, it will be shown how the relational view extends the classic notion of strategic management and how different types of networks matter in time for the competitiveness of firms but also how the spatial distribution of relationships matter for firms. The latter leads also to an investigation of the nature of clusters and how they are born and developed but most importantly how differential firm performance within clusters can be explained (allowing firms to develop a competitive advantage). If we consider that the network model is relevant for the development of entrepreneurial firms, the question arises what the limits of this model are and what the consequences are for firm development. Moreover, while research stretches the positive effects of networks, the negative effects are somehow under-researched. Research is presented that sheds some light on network liabilities. Understanding networks as an organizational configuration, the perspective is extended to other organizational configurations that drive firm competitiveness: they include research on teams as sub-units and small business groups. Concluding remarks will finally link the idea of competitive advantage to entrepreneurship
THE SUPERSYMMETRIC VERSION OF THE GREEN-SCHWARZ ANOMALY CANCELLATION MECHANISM
No full textThe N = 1, D = 10 Supergravity-Super-Yang-Mills (SUGRA-SYM) theory is plagued by ABBJ gauge and Lorentz anomalies which are cancelled via the Green-Schwarz anomaly cancellation mechanism. Due to the fact that the ABBJ anomalies are not invariant under supersymmetry (SUSY) transformations one concludes that the theory is plagued also by a SUSY anomaly. For the gauge groups SO(32) and E8 × E8 we compute this SUSY anomaly, by solving a coupled cohomology problem, and we show that it can be cancelled by subtracting from the action the known Green-Schwarz counterterm, the same which cancels also the ABBJ anomaly, the expected result. Finally, we argue that the corresponding mechanism does not apply in the dual SUGRA-SYM, related to the heterotic five-brane. © 1994
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