1,775 research outputs found
Rethinking the Social Construction of Technology Through 'Following the Actors': A Reappraisal of Technological Frames
In this paper, I summarize case study research on an information system called Connected Kids. This case study was guided by an approach to technology studies called the \'Social construction of technology\' or SCOT Bijker (1984). In discussing Connected Kids, I illustrate many of SCOT\'s main tenents, e.g. the various social interactions that surround and influence technology design. As the paper progresses, however, I focus on one concept in particular, i.e. SCOT\'s notion of a \'technological frame,\' which is used as a catch-all concept for handling the structural influences in technology design. My discussion and illustration of this concept shows that – whilst technological frames help an analyst understand, in general terms, the role structure(s) play in shaping technology – the \'heterogeneity\' of technological frames can cloak the more obvious, and potentially most influential, forces at work in technology design. In the case of Connected kids, the role of resources, and which actors had access to these resources, was critical in pointing Connected Kids down a particular trajectory. Further, this discovery emerged from listening carefully to respondents\' comments on the role of resources in their community. These comments, and my own observations on how resource-access propelled certain actors into a leadership position, led to my developing an alternative method for analyzing technological frames. The implications of this analysis are then discussed within the context of SCOT and technology studies more generally.Social Construction of Technology, Technological Frames, Information Technology
On the de la Garza Phenomenon
DOI: 10.1214/09-AOS787Deriving optimal designs for nonlinear models is, in general, challenging. One crucial step is to determine the number of support points needed. Current tools handle this on a case-by-case basis. Each combination of model,
optimality criterion and objective requires its own proof. The celebrated de la Garza Phenomenon states that under a (p − 1)th-degree polynomial regression model, any optimal design can be based on at most p design points, the minimum number of support points such that all parameters are estimable.
Does this conclusion also hold for nonlinear models? If the answer is yes, it would be relatively easy to derive any optimal design, analytically or numerically. In this paper, a novel approach is developed to address this question. Using this new approach, it can be easily shown that the de la Garza phenomenon
exists for many commonly studied nonlinear models, such as the Emax model, exponential model, three- and four-parameter log-linear models, Emax-PK1 model, as well as many classical polynomial regression models. The proposed approach unifies and extends many well-known results in the optimal design literature. It has four advantages over current tools: (i) it can be applied to many forms of nonlinear models; to continuous or discrete data; to data with homogeneous or nonhomogeneous errors; (ii) it can be applied
to any design region; (iii) it can be applied to multiple-stage optimal design and (iv) it can be easily implemented.Supported by NSF Grants DMS-07-07013 and DMS-07-48409. AMS 2000 subject classifications. Primary 62K05; secondary 62J12
Universal Optimality in Balanced Uniform Crossover Design
Kunert [Ann. Statist. 12 (1984) 1006-1017] proved that, in the class of repeated measurement designs based on t treatments, p = t periods and n = λt experimental units, a balanced uniform design is universally optimal
for direct treatment effects if t ≥ 3 and λ = 1, or if t ≥ 6 and λ = 2. This result is generalized to t ≥ 3 as long as λ ≤ (t −1)/2.Primarily sponsored by NSF Grant DMS-01-03727, National Cancer Institute Grant P01-CA48112-08 and NIH Grant P50-AT00155 ( jointly supported by the National Center for Complementary and Alternative Medicine, the Office of Dietary Supplements, the Office for Research on Women's Health, and the National Institute of General Medicine). The contents are solely the
responsibility of the authors and do not necessarily represent the official views of NIH
Leadership experiences of an American Indian education leader serving Indian students in an Indian community
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 15, 2010).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Barbara N. Martin.Vita.Ed. D. University of Missouri--Columbia 2009,The purpose of this study was to add to the knowledge base on American Indian education leadership and American Indian education by examining the leadership experiences of an American Indian leader serving predominately Indian students in a public school system on an Indian reservation. The researcher viewed the study through the lens of Tribal Critical Race Theory. Study participants included an American Indian education leader, school district faculty, graduates of the school district, and parents; all participants were tribal members. Data collection consisted of interviews, observations of the school district and reservation, and document analysis. The study findings articulated that the American Indian education leader's experiences centered on the development of cultural identity and the construction of Indigenous knowledge. The implications are that this inquiry for practice in education could impact both K-12 institutions and higher education institutions as they address the challenges of educating students from differing cultures.Includes bibliographical reference
Strong Consistency of MLE in Nonlinear Mixed-effects Models with Large Cluster Size
The search for conditions for the consistency of maximum likelihood estimators in nonlinear
mixed effects models is difficult due to the fact that, in general, the likelihood can
only be expressed as an integral over the random effects. For repeated measurements or
clustered data, we focus on asymptotic theory for the maximum likelihood estimator for
the case where the cluster sizes go to infinity, which is a minimum assumption required to validate most of the available methods of inference in nonlinear mixed-effects models. In particular, we establish sufficient conditions for the (strong) consistency of the maximum likelihood estimator of the fixed effects. Our results extend the results of Jennrich (1969)
and Wu (1981) for nonlinear fixed-effects models to nonlinear mixed-effects models
Fuzzy control of the production environment process parameters
The fuzzy control process for support of given microclimatic production environment process parameters with loss of one from values, regulating regime of process was shown. The structural schematic decisions with algorithm of functioning and oriented to existing apparatus (means of realization) was presented
Evidence for the presence of clavicles and interclavicles in sauropod dinosaurs and its implications on the furcula-clavicle homology
Clavicles, interclavicles, gastralia, and sternal ribs in sauropod dinosaurs: New reports from Diplodocidae and their morphological, functional and evolutionary implications
Osteology of Galeamopus pabsti sp. nov. (Sauropoda: Diplodocidae), with implications for neurocentral closure timing, and the cervico-dorsal transition in diplodocids
Diplodocids are among the best known sauropod dinosaurs. Numerous specimens of currently 15 accepted species belonging to ten genera have been reported from the Late Jurassic to Early Cretaceous of North and South America, Europe, and Africa. The highest diversity is known from the Upper Jurassic Morrison Formation of the western United States: a recent review recognized 12 valid, named species, and possibly three additional, yet unnamed ones. One of these is herein described in detail and referred to the genus Galeamopus. The holotype specimen of Galeamopus pabsti sp. nov., SMA 0011, is represented by material from all body parts but the tail, and was found at the Howe-Scott Quarry in the northern Bighorn Basin in Wyoming, USA. Autapomorphic features of the new species include a horizontal canal on the maxilla that connects the posterior margin of the preantorbital and the ventral margin of the antorbital fenestrae, a vertical midline groove marking the sagittal nuchal crest, the presence of a large foramen connecting the postzygapophyseal centrodiapophyseal fossa and the spinopostzygapophyseal fossa of mid- and posterior cervical vertebrae, a very robust humerus, a laterally placed, rugose tubercle on the concave proximal portion of the anterior surface of the humerus, a relatively stout radius, the absence of a distinct ambiens process on the pubis, and a distinctly concave posteroventral margin of the ascending process of the astragalus. In addition to the holotype specimen SMA 0011, the skull USNM 2673 can also be referred to Galeamopus pabsti. Histology shows that the type specimen SMA 0011 is sexually mature, although neurocentral closure was not completed at the time of death. Because SMA 0011 has highly pneumatized cervical vertebrae, the development of the lamination appears a more important indicator for individual age than neurocentral fusion patterns. SMA 0011 is one of very few sauropod specimens that preserves the cervico-dorsal transition in both vertebrae and ribs. The association of ribs with their respective vertebrae shows that the transition between cervical and dorsal vertebrae is significantly different in Galeamopus pabsti than in Diplodocus carnegii or Apatosaurus louisae, being represented by a considerable shortening of the centra from the last cervical to the first dorsal vertebra. Diplodocids show a surprisingly high diversity in the Morrison Formation. This can possibly be explained by a combination of geographical and temporal segregation, and niche partitioning
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