177,990 research outputs found
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Generalized products and associated structures on Euclidean spaces
No full textWe define a generalized product of vectors in an arbitrary finite dimensional, inner product space which depends on a finite number of real parameters and which includes as special cases the usual cross-product in R 3 and the product of n— 1 vectors in Rn. The concepts developed in this part are used to define a generalized determinant function of an arbitrary mx nmatrix. This determinant function allows us to define a general notion of non-singularity for a rectangular matrix which turns out to be necessary and sufficient for the existence of certain one-sided inverses. We obtain families of one-sided inverses of rectangular matrices and use them to construct reflexive generalized inverses which include as a special case the well-known Moore-Penrose inverse
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Capacity Expansion for Uncertain Demand with Initial Shortages
No full textFor service providers, uncertain demand for capacity and expansion lead time may create unavoidable capacity shortages, which may be allowed to accumulate before initiating an expansion. For the demand following a geometric Brownian motion process, we assume a stationary expansion policy where the timing and size of expansion are determined as fixed proportions of the capacity position. We define the service level in terms of the capacity shortages, which can be evaluated by applying pricing formulae for barrier options in finance. We observe the relationship between the two policy parameters at different specified service levels and for other model parameters.This is a proceeding published as Rahul R. Marathe and Sarah M. Ryan; Capacity Expansion for Uncertain Demand with Initial Shortages. IIE Annual Conference. Proceedings, 2005. Posted with permission.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Optimal Solution to a Capacity Expansion Problem
No full textFor a service provider, stochastic demand growth along with expansion lead times and economies of scale may encourage delaying the start of expansion until after some shortages have been accumulated. Assuming demand follows a geometric Brownian motion, we define the service level in terms of the proportion of demand satisfied, which is then analytically evaluated using financial option pricing theory. Under a stationary expansion policy, an infinite time horizon discounted expansion cost is minimized under the service level constraint, where the expansion timing and size parameters are the decision variables. With the current formulation, the problem seems to be unbounded.This is a proceeding published as Rahul R. Marathe and Sarah M. Ryan; Optimal Solution to a Capacity Expansion Problem. IIE Annual Conference. Proceedings 2006. Posted with permission.</p
Letter from R. R. Zellick, Assistant Trust Officer, Anglo California National Bank of San Francisco, to Joseph R. Goodman, October 2, 1942
No full textLetter from R. R. Zellick, Assistant Trust Officer at The Anglo California National Bank of San Francisco, to Joseph R. Goodman, regarding property owned by Dave Tatsuno. Zellick mentions a dispute between current tenants and Tatsuno, and that Tatsuno has asked Goodman to help locate trustworthy tenants.Personal correspondence, organizational records, government documents, publications, and other papers created or collected by Joseph R. Goodman documenting the forced removal and incarceration of Japanese Americans during World War II, as well as organized resistance to incarceration. Included in the collection are records of the Japanese Young Men's Christian Association and the Japanese American Citizens' League in San Francisco, including papers of the Japanese YMCA's executive secretary Lincoln Kanai; Sakai family papers; Goodman's correspondence to and from Japanese American incarcerees, organizations opposing forced removal and incarceration of Japanese Americans, the War Relocation Authority, and others; publications, photographs, and ephemera from the Topaz Relocation Center, where Goodman taught high school; War Relocation Authority records and publications; and newspaper clippings, pamphlets, and reports about forced removal and incarceration created by various government, religious, and civic organizations, in California and nationwide
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Liftings for noncomplete probability spaces
No full textThe current state of knowledge concerning liftings for noncomplete probability spaces is discussed. This is a somewhat expanded version of the author's talk given at the 1991 Summer Conference on General Topology and Applications in Honor of Mary Ellen Rudin and Her Work.PT: S; CR: BURKE MR, IN PRESS P AM MATH S BURKE MR, 1991, ISRAEL J MATH, V73, P33 BURKE MR, 1992, ISRAEL J MATH, V79, P289 CARLSON T, THEOREM LIFTING CHRISTENSEN JPR, 1974, TOPOLOGY BOREL STRUC FREMLIN DH, 1989, HDB BOOLEAN ALGEBRAS, P877 INOESCUTULCEA A, 1966, 5TH P BERK S MATH ST, V2 IONESCUTULCEA A, 1967, CONTRIBUTIONS PROB 1, P63 IONESCUTULCEA A, 1969, TOPICS THEORY LIFTIN JECH TJ, 1978, SET THEORY JOHNSON RA, 1980, P AM MATH SOC, V80, P234 JUST W, IN PRESS T AM MATH S KUPKA J, 1983, INDIANA U MATH J, V32, P717 LOSERT V, 1983, LNM, V1080, P95 MAHARAM D, 1958, P AM MATH SOC, V9, P987 SHELAH S, 1983, ISRAEL J MATH, V45, P90 TALAGRAND M, 1982, P AM MATH SOC, V84, P379 VONNEUMANN J, 1931, CRELLES J MATH, V165, P109; NR: 18; TC: 0; J9: ANN N Y ACAD SCI; PG: 4; GA: BZ86BSource type: Electronic(1
Eco-friendly Polybenzoxazine (PBZ) resins to address the age-old challenge of replacement of phenolic resins in friction materials
No full textPhenol-formaldehyde resins (Ph-Rs) have been invariably used for the last few decades as a binder/matrix in friction materials (FMs) in the industry owing to the ease of processing, excellent balance of brake-performance properties, commercial availability, and cost. However, Ph-Rs pose persistent environmental concerns due to emissions of harmful volatiles during processing (NH3, formaldehyde), apart from the challenge of limited shelf life (∼2–6 months). The present work aimed to address such issues by exploring the potential of five types of in-house synthesized Polybenzoxazines (PBZ) resins to develop brake pads for passenger cars. The composite brake pads' performance (physical, mechanical, and tribological) was compared with those based on Ph-R containing other identical ingredients in the same amount. PBZ-based brake pads exhibited notable advantages compared to PhR-based ones, such as an 8–87% increase in the fade ratio, a 9–41% higher wear resistance, and a 0.5 to 5.4 dBA reduction in noise levels. Interestingly, dimethyl substituted PBZ (PBZ-dma) based brake-pads showed the best tribological (10% lower sensitivity of μ to speed and pressure, 15–87% higher fade ratio, 35% higher wear resistance) and noise vibration performance (lower vibration and sound pressure levels by 2.8% and 0.51 dBA, respectively) apart from its 7% higher thermal stability and thermomechanical properties (∼67% higher storage modulus and 50% higher tanδ). Present work confirms the potential of PBZs (having unlimited shelf life) as the next-generation binders for FMs with superior braking performance and eco-friendliness
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