179,960 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
Characterization of a Cryogenic RF-Preamplifier for Superconducting Photodetector Readout
No full textFabrication and Characterization of an MgB2 bolometer
No full textIn this work, we present the experimental results obtained in the fabrication
and characterization of a superconducting MgB2 bolometer. The device was
made from an MgB2 meander-like structure suspended on a 500 nm thick
SiN membrane. The MgB2 meander line was 50 μm wide and 7.6 mm long
and it was defined by optical lithography and dry etching. The SiN
membrane had an area of 1.3 mm× 1.3 mm and it was obtained by a silicon
micromachining technique. The electrical and thermal properties of the
device were measured at low temperature in a closed-cycle cryocooler. The
resulting Tc of the meander was unchanged with respect to the unprocessed
film and the transport properties, measured in voltage-biased mode, indicated
a value for Jc of the order of 105 A cm−2 at 27 K. The logarithmic sensitivity
of the bolometer turned out to be higher than 150. The study of the thermal
properties of the bolometer on the membrane showed a thermal conductance
of the order 10−5 WK−1 at a working temperature of 32 K. The bolometer,
irradiated by a chopped laser beam, showed a cut-off frequency of 94 Hz. The
maximum experimental responsivity was estimated to be 2.3 × 103 VW−1
Lacche da macromolecole naturali, ad effetto barriera ai gas, modulabili in situ, e relativi metodi di preparazione
No full textLa presente invenzione si riferisce a lacche essenzialmente da macromolecole di origine naturale, aventi effetto barriera ai gas, modulabile in situ, destinate in particolare per il rivestimento di substrati plastici, in specie films e contenitori, per applicazioni che riguardano vari settori, in particolare quello dell’imballaggio alimentare e quello medicale. Più in particolare, il trovato concerne matrici naturali (gelatina, chitosano, chitina, pectina, glutine, caseina, zeina, proteine del siero del latte, carragenani, gomma di guar, gomma xantano, alginati, amido, cellulosa nelle sue varie forme) che possono essere associate a componenti inorganiche (alcossidi metallici) e polimeri di sintesi (polivinil alcool, polivinil acetato), per dare origine, attraverso un processo ben definito e controllato, a strutture ibride sotto forma di coatings trasparenti, caratterizzate dall’elevata capacità barriera nei confronti dei gas (ossigeno in particolare) ed unica adesione del coating medesimo al substrato plastico
Proprietà diffusionali, ottiche e meccaniche di tre Differenti films plastici laccati con un coating edibile a base lipo-proteica
No full text"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.
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
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
Behavior of semi-inclusive sphericity distributions and a two-component uncorrelated cascade model
No full textA simple two component uncorrelated cascade model is proposed which reproduces the semi-inclusive Sphericity distributions observed in lowp T hadron-hadron collisions. It is pointed out that if α is an exponential parameter inserted into the quark-quark structure function, theS dependence of the semi-inclusive sphericity distribution for multiplicityn goes as exp (−α/nS). This conclusion agrees extremely well with the experimental data
Project of Thin Targets for the NUMEN Experiment
No full textAbstract
.
The goal of the NUMEN collaboration is
the measurement of
the cross sections
of
Double Charge Exchange reactions for several couple of ion projectile
-
target
, in order to provide
helpful data
to
study the nuclear matrix elements of the neutrino
-
le
ss
double β
-
decay. The need
of big statistics and high precision in the measurements require the use of high intensity beams
and very thin targets. This creates some problems to the design of the target frame and to the
dissipation of the heat generated by
the beam. The present paper reports
a possible
solution for
the cooling system and the production technique of
a tin target, together with the results of the
preliminary tests of heat dissipation
- …
