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CHARLES A. SANTO 《Journal of Urban Affairs》2007,29(5):455-479
ABSTRACT: A host of empirical studies have indicated that stadiums and arenas have no significant impact on metropolitan area income or employment. In light of this evidence, the continued proliferation of public investment in sports facilities begs the question: Is there some other justification for this spending, or are policymakers simply acting against the public interest (either irrationally, or in response to political‐economic influences)? A possibility that has not been fully explored is the notion that stadiums and teams generate tangible and intangible consumption benefits that could support some level of public investment. This research builds on a small foundation of literature that is moving discussion beyond the economic catalyst debate by providing an empirical measure of the consumption benefits that accrue to a region as the result of hosting a major league sports team. A contingent valuation survey is used to quantify the consumption benefits that would be associated with the relocation of a major league baseball team to Portland, Oregon. An empirical measure of the region's aggregate willingness to pay for the benefits associated with hosting a team is disaggregated into option and existence values, which can then be compared to any proposed level of public contribution to a new stadium. The findings indicate that consumption benefits would only support a capital investment of approximately $74 million; a figure far smaller than the typical stadium subsidy. The majority of projected benefits are associated with expected public goods and externalities, rather than anticipated attendance, indicating that an equitable financing plan should employ nonuser revenue sources. The level of projected benefits does not vary by locality within the metropolitan area, which argues for a regional cost‐sharing approach. The willingness of residents to pay for stadium construction is tempered by a concern about other pressing social needs in the Portland area and a reaction to the current tax climate. 相似文献
84.
CHARLES HENRY LUIS MATEUS ROCHA 《控制论与系统》2013,44(6):541-554
Both representational and self organizing approaches to language avoid in different ways the concept of symbol We argue that representationalism denies the particular aspects of a subjects embodiment while the self organizing paradigm refuses to address the utility of the concept of symbol and its evolutionary relationship with an environment We call for an inclusive approach that considers the syntactic semantic and pragmatic aspects of language We further offer a mathematical structure defined in terms of fuzzy set and evidence theories as a model of linguistic categories under this inclusive framework 相似文献
85.
A hot stream of a very viscous fluid, such as a polymer, may be cooled in a heal exchanger consisting of multiple parallel passages. However, if a quite uniform temperature distribution is desired in the exit stream, the fluid flowing through each of the passages must be cooled to very nearly the same temperature. An analytical treatment of heat transfer and pressure drop in viscous flow between parallel plates during cooling reveals the operating conditions and passage geometry required to achieve this goal. Solution of the equation obtained depends only on the physical properties of the fluid and the cooler geometry. Non-Newtonian behavior of the fluid is approximated by a power-law function. A unique type of heat exchanger was designed on the basis of this analysis. 相似文献
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ARCOT L. NARESH Staff Consultant CHARLES T. JAHREN Assistant Professor 《Civil Engineering and Environmental Systems》2013,30(2):129-144
Repetitive construction processes exhibit improvement in production rate as repetitions increase. A learning curve can be developed for such construction processes that can improve the predictive accuracy for the early portions of project schedules. This paper discusses a method for incorporating learning development in a construction simulation model. The case study model represents the construction of a guide wall for a lock using a mobile cofferdam. The impact of including learning development on model results is reported as well as a sensitivity analysis. 相似文献
88.
CHARLES H. SMITH 《国际通用系统杂志》2013,42(4):359-384
In this, the First part of a two part work, a general model of spatial organization is introduced. Following a brief synopsis of some of Spinoza's and Leibniz's views regarding natural structure, an extension of the Spinozian model is presented in which the attribute spatial extension is portrayed as a relational system that implicitly underlies the differentiation of sensible space into “modifications” (“natural systems”) and the latter's subdifferentiation into “modes” On the basis of this model, all instances of modal differentiation are understood to take place in a manner explained by this relational structure, the existence (but not the specific characteristics) of which is initially assumed. The nature of the structure is then deduced according to a “most-probable-state” kind of logic; next, it is demonstrated via simulation that the resulting aspatial model of internal relations has a corresponding spatial interpretation (and therefore, in theory, that sensible space structures can be supported by the particular rational ordering posed). The matter of how to apply the model to the study of real world systems is taken up last; discussion focuses on related aspects of the treatment of equilibrium and nonequilibrium systems and the recognition and measurement of modal structures. 相似文献
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CHARLES A. GOODWIN † H. KENT BOWEN W. D. KINGERY 《Journal of the American Ceramic Society》1975,58(7-8):317-320
Transmission electron microscopy was used to observe variations in composition in single crystals of Fe y Mn1– y O1+] x on a scale of 100 to 500 Å. Compositional fluctuations were resolved as lamellar-like striations oriented primarily in the [100] direction. Specimens had been equilibrated at 900°C in oxygen partial pressures within the monoxide phase region and then quenched to room temperature. A region of solid-solid immiscibility in the monoxide phase field is proposed. A different submicrostructure resulted from low-temperature decomposition (150°C) due to localized heating when samples were prepared by ion-bombardment thinning. 相似文献