9,629 research outputs found
Technological Capability and Productivity Growth: An Industrialized / Industrializing Country Comparison
The importance of technical change as a crucial element explaining inter-country differences in levels and rates of change in industrial productivity has been increasingly acknowledged. Hence, growing significance has been attached to developing the capability to generate such change. However, the perceived nature of that capability (described here as technological capability) and its links to productivity growth are still poorly understood. This paper empirically explores the links between (i) technological capability (the causal variable) (ii) the generation of technical changes (the intermediate variable) and (iii) productivity growth (the end-result variable). In particular, it examines organizational dimensions of technological capability.
L'importance des changements techniques comme éléments clés expliquant les différences entre pays quant aux niveaux et aux taux de productivité industrielle est de plus en plus reconnue. En conséquence, il y a un intérêt croissant quant au développement des capacités nécessaires à de tels changements. Cependant, la nature de cette capacité (dite capacité technologique) et ses liens avec la croissance de productivité est encore peu comprise. Cet article explore empiriquement les liens entre (i) la capacité technologique (variable causale) (ii) la génération de changements techniques (variable intermédiaire) et (iii) la croissance de productivité (variable résultante). En particulier, il examine les dimensions organisationnelles de la capacité technologique.technological capability, organizational systems, technical change, productivity growth, pulp and paper, India, Canada, capacité technologique, systèmes organisationnels, changement technique, croissance de productivité, pâtes et papiers, Inde, Canada
Informal Thinkering: How Is It Important?
This paper examines innovation processes or technical change-generation processes at the firm level. It emphasizes the notion that the element of technical and technological change that is a determinant of productivity growth is strongly induced by internal factors related to the firm's behavior, via investment in R&D but also, and importantly, on the basis of informal thinkering within plants. This research is unique in that it seeks first, to examine the pattern of technical change and its ensuing productivity growth, and second, to make a comparison between an industrialized and an industrializing country. This comparison is conducted by empirically comparing mills in the pulp and paper manufacturing sector in two countries: Canada and India. The overall analysis is based on direct observations at the mill level, face-to-face interviews and on analysis of mill documentary records. This paper highlights the importance of managing change as a continuous process. The introduction of intermittent, step-jump technical changes contributed little to explain the differences in performance between the mills. Much more important are (i) the continuing sequences of smaller investments in technical change, often linked to the larger step-jumps, and (ii) the existence of steady streams of changes and improvements that are unrecorded as capital expenditure
Cet article examine des processus d'innovation ou de génération de changements techniques au niveau de la firme. Il met l'emphase sur le fait que les paramètres clés connexes aux changements techniques et technologiques ayant un impact sur la croissance de productivité sont induits par des facteurs behavioraux internes à la firme. Les changements peuvent être le résultat d'investissement dans la R&D,0501s aussi, et de façon significative, le résultat de processus de conceptions informelles à l'intérieur des firmes. Cette recherche examiner dans un premier temps des processus de changements techniques et la croissance de productivité en résultant. Dans un deuxième temps, elle fait une analyse comparative entre pays industrialisés et s'industrialisant. Cette étude empirique est basée sur des données de première0501n (observations directes, entrevues personnelles, documents internes) collectées dans neuf usines de pâtes et papiers dans deux pays (Canada et Inde). Ce papier met en évidence l'importance de gérer le changement comme un processus continu. L'introduction de changements techniques par sauts intermittents contribue peu à expliquer les différences de croissance de productivité entre les usines. Plus significatives sont (i) les séquences continues de petits investissements (changements techniques), souvent liés aux plus grands changements par sauts, et (ii) l'existence d'un flux continu de changements et d'améliorations qui ne sont pas officiellement enregistrés (aux livres, de façon comptable) comme des investissements en capitaux.Technical change, incremental change, performance measure-ment, continuous improvement, capital investment, pulp and paper, India, Canada, Changement technique, changements par incréments, mesures de performance, amélioration continue, investment capital, pâtes et papiers, Inde, Canada
Ultrafast Transient Dynamics of Adsorbates on Surfaces Deciphered: The Case of CO on Cu(100)
Time-resolved vibrational spectroscopy constitutes an invaluable experimental
tool for monitoring hot-carrier induced surface reactions. However, the absence
of a full understanding on the precise microscopic mechanisms causing the
transient spectral changes has been limiting its applicability. Here we
introduce a robust first-principles theoretical framework that successfully
explains both the nonthermal frequency and linewidth changes of the CO internal
stretch mode on Cu(100) induced by femtosecond laser pulses. Two distinct
processes engender the changes: electron-hole pair excitations underlie the
nonthermal frequency shifts, while electron-mediated vibrational mode coupling
gives rise to linewidth changes. Furthermore, the origin and precise sequence
of coupling events are finally identified.Comment: Article as accepted for publication in Physical Review Letters; 5
pages, 2 figures, 1 tabl
White Dwarf Cosmochronology in the Solar Neighborhood
The study of the stellar formation history in the solar neighborhood is a
powerful technique to recover information about the early stages and evolution
of the Milky Way. We present a new method which consists of directly probing
the formation history from the nearby stellar remnants. We rely on the volume
complete sample of white dwarfs within 20 pc, where accurate cooling ages and
masses have been determined. The well characterized initial-final mass relation
is employed in order to recover the initial masses (1 < M/Msun < 8) and total
ages for the local degenerate sample. We correct for moderate biases that are
necessary to transform our results to a global stellar formation rate, which
can be compared to similar studies based on the properties of main-sequence
stars in the solar neighborhood. Our method provides precise formation rates
for all ages except in very recent times, and the results suggest an enhanced
formation rate for the solar neighborhood in the last 5 Gyr compared to the
range 5 < Age (Gyr) < 10. Furthermore, the observed total age of ~10 Gyr for
the oldest white dwarfs in the local sample is consistent with the early
seminal studies that have determined the age of the Galactic disk from stellar
remnants. The main shortcoming of our study is the small size of the local
white dwarf sample. However, the presented technique can be applied to larger
samples in the future.Comment: 25 pages, 10 figures, accepted for publication in the Astrophysical
Journa
Utilization of tmRNA sequences for bacterial identification
In recent years, molecular approaches based on nucleotide sequences of ribosomal RNA (rRNA) have become widely used tools for identification of bacteria [1-4]. The high degree of evolutionary conservation makes 16S and 23S rRNA molecules very suitable for phylogenetic studies above the species level [3-5]. More than 16,000 sequences of 16S rRNA are presently available in public databases [4,6]. The 16S rRNA sequences are commonly used to design fluorescently labeled oligonucleotide probes. Fluorescence in situ hybridization (FISH) with these probes followed by observation with epifluorescence microscopy allows the identification of a specific microorganism in a mixture with other bacteria [2-4]. By shifting probe target sites from conservative to increasingly variable regions of rRNA, it is possible to adjust the probe specificity from kingdom to species level. Nevertheless, 16S rRNA sequences of closely related strains, subspecies, or even of different species are often identical and therefore can not be used as differentiating markers [3]. Another restriction concerns the accessibility of target sites to the probe in FISH experiments. The presence of secondary structures, or protection of rRNA segments by ribosomal proteins in fixed cells can limit the choice of variable regions as in situ targets for oligonucleotide probes [7,8]. One way to overcome the limitations of in situ identification of bacteria is to use molecules other than rRNA for phylogenetic identification of bacteria, for which nucleotide sequences would be sufficiently divergent to design species specific probes, and which would be more accessible to oligonucleotide probes. For this purpose we investigated the possibility of using tmRNA (also known as 10Sa RNA; [9-11]). This molecule was discovered in E. coli and described as small stable RNA, present at ~1,000 copies per cell [9,11]. The high copy number is an important prerequisite for FISH, which works best with naturally amplified target molecules. In E. coli, tmRNA is encoded by the ssrA gene, is 363 nucleotides long and has properties of tRNA and mRNA [12,13]. tmRNA was shown to be involved in the degradation of truncated proteins: the tmRNA associates with ribosomes stalled on mRNAs lacking stop codons, finally resulting in the addition of a C-terminal peptide tag to the truncated protein. The peptide tag directs the abnormal protein to proteolysis [14,15]. 165 tmRNA sequences have so far (August 2001; The tmRNA Website: http://www.indiana.edu/~tmrna/) been determined [16,17]. The tmRNA is likely to be present in all bacteria and has also been found in algae chloroplasts, the cyanelle of Cyanophora paradoxa and the mitochondrion of the flagellate Reclinomonas americana[10,17,18]
Alien Registration- Tremblay, George J. (Auburn, Androscoggin County)
https://digitalmaine.com/alien_docs/30610/thumbnail.jp
Superintegrability of the Tremblay-Turbiner-Winternitz quantum Hamiltonians on a plane for odd
In a recent FTC by Tremblay {\sl et al} (2009 {\sl J. Phys. A: Math. Theor.}
{\bf 42} 205206), it has been conjectured that for any integer value of ,
some novel exactly solvable and integrable quantum Hamiltonian on a plane
is superintegrable and that the additional integral of motion is a th-order
differential operator . Here we demonstrate the conjecture for the
infinite family of Hamiltonians with odd , whose first member
corresponds to the three-body Calogero-Marchioro-Wolfes model after elimination
of the centre-of-mass motion. Our approach is based on the construction of some
-extended and invariant Hamiltonian \chh_k, which can be interpreted
as a modified boson oscillator Hamiltonian. The latter is then shown to possess
a -invariant integral of motion \cyy_{2k}, from which can be
obtained by projection in the identity representation space.Comment: 14 pages, no figure; change of title + important addition to sect. 4
+ 2 more references + minor modifications; accepted by JPA as an FT
Magnetic Flux Channel Antenna Design in Conformal Applications
Magnetic Flux Channels (MFC) and Magneto-Dielectric Wire Antennas (MDWA) are effective, and in some cases, superior alternatives to traditional metallic antennas, in conformal and electrically small applications at the cost of fabrication and feed complexity. The frequency dispersive nature of magnetic material constituent parameters imposes constraints on the antenna design process, which were not fully developed in prior art. This research quantifies the key differences between the operating regions of magneto-dielectric materials for antenna applications and demonstrates the effectiveness of numerical method augmented modal analysis in the design process, regardless of operating region. Modeling challenges associated with MDWAs are addressed leading to novel full wave modeling results for antennas designed in accordance with early MDWA design law. The results clarify the limitations of certain prior art in the recommended design process, and provide needed support for later-art material selection and design recommendations
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