16,152 research outputs found
The Permeability of Network Boundaries: Strategic Alliances in the Japanese Electronics Industry in the 1990s
This paper looks at the choice of strategic partners for alliance formation in the Japanese electronics industry during the post-bubble economic period 1992-97. Results from a dyad analysis of 128 companies suggest that firms tend to look for partners within their existing vertical keiretsu networks of organizations for alliances that target the creation of resources that build on existing knowledge (production or distribution) but that this common keiretsu effect disappears for alliances that involve new knowledge creation (new product or technology development). The role of corporate networks, environmental uncertainty and their implications for our understanding of strategic alliance formation and the dynamics of social networks are discussed.
Engineering data compendium. Human perception and performance. User's guide
The concept underlying the Engineering Data Compendium was the product of a research and development program (Integrated Perceptual Information for Designers project) aimed at facilitating the application of basic research findings in human performance to the design and military crew systems. The principal objective was to develop a workable strategy for: (1) identifying and distilling information of potential value to system design from the existing research literature, and (2) presenting this technical information in a way that would aid its accessibility, interpretability, and applicability by systems designers. The present four volumes of the Engineering Data Compendium represent the first implementation of this strategy. This is the first volume, the User's Guide, containing a description of the program and instructions for its use
A fast data acquisition system for the study of transient events by high repetition rate time-of-flight mass spectrometry
Recent advances in commercially available data acquisition electronics embodying high speed A/D conversion coupled to increased memory storage have now made practical (at least within time intervals of a third of a millisecond or more) the capturing of all of the data generated by a high repetition rate time-of-flight mass spectrometer producing complete spectra every 25 to 35 microseconds. Such a system was assembled and interfaced with a personal computer for control and management of data. The applications are described for recording time-resolved spectra of individual vapor plumes induced from the pulsed-laser heating of material. Each laser pulse triggers the system to generate automatically a 3-dimensional (3-D) presentation of the time-resolved spectra with m/z labeling of the major mass peaks, plus an intensity versus time display of both the laser pulse and the resulting vapor pulse. The software also permits storing of data and its presentation in various additional forms
The Supply Side of Innovation: H-1B Visa Reforms and US Ethnic Invention
This study evaluates the impact of high-skilled immigrants on US technology formation. Specifically, we use reduced-form specifications that exploit large changes in the H-1B visa program. Fluctuations in H-1B admissions levels significantly influence the rate of Indian and Chinese patenting in cities and firms dependent upon the program relative to their peers. Most specifications find weak crowding-in effects or no effect at all for native patenting. Total invention increases with higher admission levels primarily through the direct contributions of ethnic inventors.Innovation, Research and Development, Patents, Scientists, Engineers, Inventors, H-1B, Immigration, Ethnicity, India, China, Endogenous Growth.
Deterministic Time-Space Tradeoffs for k-SUM
Given a set of numbers, the -SUM problem asks for a subset of numbers
that sums to zero. When the numbers are integers, the time and space complexity
of -SUM is generally studied in the word-RAM model; when the numbers are
reals, the complexity is studied in the real-RAM model, and space is measured
by the number of reals held in memory at any point.
We present a time and space efficient deterministic self-reduction for the
-SUM problem which holds for both models, and has many interesting
consequences. To illustrate:
* -SUM is in deterministic time and space
. In general, any
polylogarithmic-time improvement over quadratic time for -SUM can be
converted into an algorithm with an identical time improvement but low space
complexity as well. * -SUM is in deterministic time and space
, derandomizing an algorithm of Wang.
* A popular conjecture states that 3-SUM requires time on the
word-RAM. We show that the 3-SUM Conjecture is in fact equivalent to the
(seemingly weaker) conjecture that every -space algorithm for
-SUM requires at least time on the word-RAM.
* For , -SUM is in deterministic time and
space
Strapdown inertial measurement unit computer, volume 1 Final report
Strapdown inertial measurement unit design, calculations, and operating instruction
The Dynamics of Firm Lobbying
We study the determinants of the dynamics of firm lobbying behavior using a panel data set covering 1998-2006. Our data exhibit three striking facts: (i) few firms lobby, (ii) lobbying status is strongly associated with firm size, and (iii) lobbying status is highly persistent over time. Estimating a model of a firm's decision to engage in lobbying, we find significant evidence that up-front costs associated with entering the political process help explain all three facts. We then exploit a natural experiment in the expiration in legislation surrounding the H-1B visa cap for high-skilled immigrant workers to study how these costs affect firms' responses to policy changes. We find that companies primarily adjusted on the intensive margin: the firms that began to lobby for immigration were those who were sensitive to H-1B policy changes and who were already advocating for other issues, rather than firms that became involved in lobbying anew. For a firm already lobbying, the response is determined by the importance of the issue to the firm's business rather than the scale of the firm's prior lobbying efforts. These results support the existence of significant barriers to entry in the lobbying process.
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