7,204 research outputs found
Observations of HONO by laser-induced fluorescence at the South Pole during ANTCI 2003
Observations of nitrous acid (HONO) by laser-induced fluorescence (LIF) at the South Pole taken during the Antarctic Troposphere Chemistry Investigation (ANTCI), which took place over the time period of Nov. 15, 2003 to Jan. 4, 2004, are presented here. The median observed mixing ratio of HONO 10 m above the snow was 5.8 pptv (mean value 6.3 pptv) with a maximum of 18.2 pptv on Nov 30th, Dec 1st, 3rd, 15th, 17th, 21st, 22nd, 25th, 27th and 28th. The measurement uncertainty is ±35%. The LIF HONO observations are compared to concurrent HONO observations performed by mist chamber/ion chromatography (MC/IC). The HONO levels reported by MC/IC are about 7.2 ± 2.3 times higher than those reported by LIF. Citation: Liao, W., A. T. Case, J. Mastromarino, D. Tan, and J. E. Dibb (2006), Observations of HONO by laser-induced fluorescence at the South Pole during ANTCI 2003, Geophys. Res. Lett., 33, L09810, doi:10.1029/2005GL025470
Stochastic evolution of four species in cyclic competition
We study the stochastic evolution of four species in cyclic competition in a
well mixed environment. In systems composed of a finite number of particles
these simple interaction rules result in a rich variety of extinction
scenarios, from single species domination to coexistence between
non-interacting species. Using exact results and numerical simulations we
discuss the temporal evolution of the system for different values of , for
different values of the reaction rates, as well as for different initial
conditions. As expected, the stochastic evolution is found to closely follow
the mean-field result for large , with notable deviations appearing in
proximity of extinction events. Different ways of characterizing and predicting
extinction events are discussed.Comment: 19 pages, 6 figures, submitted to J. Stat. Mec
Induction, Philosophical Conceptions of
How induction was understood took a substantial turn during the Renaissance. At the beginning, induction was understood as it had been throughout the medieval period, as a kind of propositional inference that is stronger the more it approximates deduction. During the Renaissance, an older understanding, one prevalent in antiquity, was rediscovered and adopted. By this understanding, induction identifies defining characteristics using a process of comparing and contrasting.
Important participants in the change were Jean Buridan, humanists such as Lorenzo Valla and Rudolph Agricola, Paduan Aristotelians such as Agostino Nifo, Jacopo Zabarella, and members of the medical faculty, writers on philosophy of mind such as the Englishman John Case, writers of reasoning handbooks, and Francis Bacon
Comparative analysis of rigidity across protein families
We present a comparative study in which 'pebble game' rigidity analysis is applied to multiple protein crystal structures, for each of six different protein families. We find that the main-chain rigidity of a protein structure at a given hydrogen bond energy cutoff is quite sensitive to small structural variations, and conclude that the hydrogen bond constraints in rigidity analysis should be chosen so as to form and test specific hypotheses about the rigidity of a particular protein. Our comparative approach highlights two different characteristic patterns ('sudden' or 'gradual') for protein rigidity loss as constraints are removed, in line with recent results on the rigidity transitions of glassy networks
Lean manufacturing culture: The role of human perceptions of standardized work
The final publication is available at IOS Press through http://dx.doi.org/10.3233/978-1-61499-902-7-523.Lean implementation and its sustainability are strongly coupled with organizational culture and consequently the culture defines success. Organizational culture is strongly linked with organizational dynamics. Work standardization is one of the lean tools whose role in terms of organizational performance improvement has been claimed in the literature; however, its implications in terms of employee's perceptions are still controversial. This study aims at investigating the effect of position on employee's perception about the standardized work. Four textile manufacturing companies in Pakistan were selected for the purpose of data collection, where the implementation level of the tool and organizational maturity towards lean adoption were initially measured. A questionnaire was administered to 326 employees from these organizations. The overall data sample was divided into two categories (white-collar and blue-collar). Data analysis was by F-tests (for identifying significance levels) and separate regression analyses (for identifying variables associated with negative perceptions of employees). A significant difference was found between white-collar employees, who were generally positive about the standardization of work, and the blue-collar employees that had negative perceptions. Moreover, the study concluded that positive perceptions about standardized work are directly linked with job satisfaction and inversely linked with job stress
The inexorable resistance of inertia determines the initial regime of drop coalescence
Drop coalescence is central to diverse processes involving dispersions of
drops in industrial, engineering and scientific realms. During coalescence, two
drops first touch and then merge as the liquid neck connecting them grows from
initially microscopic scales to a size comparable to the drop diameters. The
curvature of the interface is infinite at the point where the drops first make
contact, and the flows that ensue as the two drops coalesce are intimately
coupled to this singularity in the dynamics. Conventionally, this process has
been thought to have just two dynamical regimes: a viscous and an inertial
regime with a crossover region between them. We use experiments and simulations
to reveal that a third regime, one that describes the initial dynamics of
coalescence for all drop viscosities, has been missed. An argument based on
force balance allows the construction of a new coalescence phase diagram
Assessment of Corporate Social Responsibility (CSR) awareness and practices in manufacturing sector of Pakistan
Globalization and mass communication have significantly influenced the socio-economic growth of countries and organizations are under immense pressure to develop their businesses in a more socially responsible way. Consequently, Corporate Social Responsibility (CSR) has emerged as a business development concept. CSR acknowledgement is low in south Asian countries both at state and corporate levels. Pakistan, being a developing country, is no exception and the manufacturing sector, which is the third largest contributing sector to the economy, is facing the challenge of corporate social compliance. This study explores the awareness level amongst employees in the manufacturing sector and also evaluates the practices of CSR activities in these organizations. The study is mainly focused on the textile and automobile sectors and shows greater CSR awareness in the automobile sector than the textile sector; however, there are many organizations where the concept of CSR is unknown. The findings of this research will help organizations in enhancing understanding of CSR amongst employees and will also allow manufacturing industries to improve their implementation against identified weak areas. Increased levels of social compliance will ultimately help organizations in promoting their businesses in the global market
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