Manufacturing Wage Dispersion: An End Game Interpretation

macroeconomics, manufacturing, wage dispersion, cyclical swings

Effects of closed immersion filtered water flow velocity on the ablation threshold of bisphenol A polycarbonate during excimer laser machining

A closed flowing thick film filtered water immersion technique ensures a controlled geometry for both the optical interfaces of the flowing liquid film and allows repeatable control of flow-rate during machining. This has the action of preventing splashing, ensures repeatable machining conditions and allows control of liquid flow velocity. To investigate the impact of this technique on ablation threshold, bisphenol A polycarbonate samples have been machined using KrF excimer laser radiation passing through a medium of filtered water flowing at a number of flow velocities, that are controllable by modifying the liquid flow rates. An average decrease in ablation threshold of 7.5% when using turbulent flow velocity regime closed thick film filtered water immersed ablation, compared to ablation using a similar beam in ambient air; however, the use of laminar flow velocities resulted in negligible differences between closed flowing thick film filtered water immersion and ambient air. Plotting the recorded threshold fluence achieved with varying flow velocity showed that an optimum flow velocity of 3.00 m/s existed which yeilded a minimum ablation threshold of 112 mJ/cm2. This is attributed to the distortion of the ablation plume effected by the flowing immersion fluid changing the ablation mechanism: at laminar flow velocities Bremsstrahlung attenuation decreases etch rate, at excessive flow velocities the plume is completely destroyed, removing the effect of plume etching. Laminar flow velocity regime ablation is limited by slow removal of debris causing a non-linear etch rate over ‘n’ pulses which is a result of debris produced by one pulse remaining suspended over the feature for the next pulse. The impact of closed thick film filtered water immersed ablation is dependant upon beam fluence: high fluence beams achieved greater etch efficiency at high flow velocities as the effect of Bremsstrahlung attenuation is removed by the action of the fluid on the plume; low fluences loose efficiency as the beam makes proportionally large fluence losses at it passes through the chamber window and immersion medium

Pioneer Venus

Venus before Pioneer, the Pioneer Venus mission, Pioneer Venus spacecraft, scientific investigation, mission to Venus scientific results, and results of Soviet studies of Venus are addressed. A chronology of exploration of Venus from Earth before the Pioneer Venus mission and Venus nomenclature and mythology are provided

A semi-classical model of proton tunnelling in hydrogen-bonded compounds

Bibliography: pages 233-238.Two back-to-back Morse potentials are used to model the protonic potential in a hydrogen bond. A mathematical method is developed to obtain semi-classical solutions for the eigenvalues and eigenfunctions of the potential. Particular care is taken over the form of approximation used in the vicinity of the barrier top. The double Morse potential is then used as the fundamental element in the analysis of the proton dynamics in a number of hydrogen-bonded species: a) Chromous acid. A consistent, quantitative explanation is found for the νs(OH)/vs(OD) bands in the mid-infrared spectra of CrOOH/CrOOD. The 226 cm⁻¹ band in the far infrared and neutron scattering spectra of CrOOH is shown to be caused by the protonic tunnelling mode. b) Carboxylic and Dicarboxylic acids. The 140 cm⁻¹ protonic upper state splitting in dimeric formic acid proposed by Excoffon and Marechal (1972) is shown to be supported by the double Morse potential analysis. The analysis suggest's however that the two hydrogen-bonded protons in (HCOOH)₂ tunnel independently. The anomalous vs(OH)/vs(OD) intensity ratios observed in the infrared spectra of both adipic acid and dimeric formic acid could not be explained in terms of mechanical anharmonicity alone. The protonic tunnelling frequency in crystalline formic acid is shown to be about 23 cm⁻¹ , which supports the order-disorder interpretation of the observed phase transition in this crystal. c) Potassium Dihydrogen Phosphate (KDP). The crystallographic and infrared spectroscopic data for KDP and DKDP are interpreted consistently using the double Norse potential. The bare single-particle tunnelling frequency Ω is estimated to be 320 ± 10 cm⁻¹ and the overtone band at 4600 cm⁻¹ in the infrared spectrum of KDP is shown to be a :0 →:3> single particle transition. The model is capable of predicting the temperature and pressure dependence of both the protonic tunnelling frequency and the protonic inter-site separation δ. The soft-mode Raman data of Peercy (1975) is re-analysed allowing for the temperature dependence of Ω

Healthy Cities in a global and regional context

Since the beginning of the WHO European Healthy Cities Network in 1987, the global and regional contexts for the promotion of health and well-being have changed in many ways. First, in 2000, the United Nations Millennium Goals explicitly and implicitly addressed health promotion and prevention at the global and regional levels. Second, the concern for sustainable development at the Rio Conference in 1992 was confirmed at the World Summit in Johannesburg in 2002. During the same period, in many regions including Europe, the redefinition of the roles and responsibilities of national, regional and local governments, reductions in budgets of public administrations, the privatization of community and health services, the instability of world trade, the financial system and employment, migration flows, relatively high levels of unemployment (especially among youth and young adults) have occurred in many countries in tandem with negative impacts on specific policies and programmes that are meant to promote health. Since 1990, the European Commission has been explicitly concerned about the promotion of health, environment and social policies by defining strategic agendas for the urban environment, sustainable development and governance. However, empirical studies during the 1990s show that urban areas have relatively high levels of tuberculosis, respiratory and cardiovascular diseases, cancer, adult obesity, malnutrition, tobacco smoking, poor mental health, alcohol consumption and drug abuse, sexually transmitted diseases (including AIDS), crime, homicide, violence and accidental injury and death. In addition, there is evidence that urban populations in many industrialized countries are confronted with acute new health problems stemming from exposure to persistent organic pollutants, toxic substances in building structures, radioactive waste and increasing rates of food poisoning. These threats to public health indicate an urgent need for new strategic policies and research agendas that address the complex interrelations between urban ecosystems, sustainable development, human health and well-being. The WHO Healthy Cities project is one important vector for achieving this objective at both global and regional level

A linked data approach to publishing complex scientific workflows

Past data management practices in many fields of natural science, including climate research, have focused primarily on the final research output - the research publication - with less attention paid to the chain of intermediate data results and their associated metadata, including provenance. Data were often regarded merely as an adjunct to the publication, rather than a scientific resource in their own right. In this paper, we attempt to address the issues of capturing and publishing detailed workflows associated with the climate/research datasets held by the Climatic Research Unit (CRU) at the University of East Anglia. To this end, we present a customisable approach to exposing climate research workflows for the effective re-use of the associated data, through the adoption of linked-data principles, existing widely adopted citation techniques (Digital Object Identifier) and data exchange mechanisms (Open Archives Initiative Object Reuse and Exchange)

Landmarks in Insulin Research

Ever since the discovery of insulin and its role in the regulation of glucose uptake and utilization, there has been great interest in insulin, its structure and the way in which it interacts with its receptor and effects signal transduction. As the 90th anniversary of the discovery of insulin approaches, it is timely to provide an overview of the landmark discoveries relating to the structure and function of this remarkable molecule and its receptor

Invariant manifolds and orbit control in the solar sail three-body problem

In this paper we consider issues regarding the control and orbit transfer of solar sails in the circular restricted Earth-Sun system. Fixed points for solar sails in this system have the linear dynamical properties of saddles crossed with centers; thus the fixed points are dynamically unstable and control is required. A natural mechanism of control presents itself: variations in the sail's orientation. We describe an optimal controller to control the sail onto fixed points and periodic orbits about fixed points. We find this controller to be very robust, and define sets of initial data using spherical coordinates to get a sense of the domain of controllability; we also perform a series of tests for control onto periodic orbits. We then present some mission strategies involving transfer form the Earth to fixed points and onto periodic orbits, and controlled heteroclinic transfers between fixed points on opposite sides of the Earth. Finally we present some novel methods to finding periodic orbits in circumstances where traditional methods break down, based on considerations of the Center Manifold theorem

Excimer laser machining of bisphenol A polycarbonate under closed immersion filtered water with varying flow velocities and the effects on the etch rate

Until now, progress in laser ablation micromachining has been significantly limited with respect to feature miniaturization and output yield by ablation-generated debris. Gas-jetting techniques have proven to be inadequate and vacuum environments are unwieldy in an industrial setting. To this end, a controlled geometry for both the optical interfaces of a flowing liquid film can be provided by a closed flowing thick film filtered water immersion technique. This ensures repeatable machining conditions and allows control of liquid flow velocity. To investigate the impact of this technique on etch rate, bisphenol A polycarbonate samples have been machined using KrF excimer laser radiation passing through a medium of filtered water flowing at a number of flow velocities that are controllable by modifying liquid flowrate. A mean increase in etch rate of 8.5 per cent when using a turbulent flow velocity regime immersed ablation over ablation in ambient air was recorded. However, use of laminar flow velocities resulted in a mean loss of 26.6 per cent in etch rate compared to ablation in ambient air. Plotting the recorded etch rate achieved with respect to flow velocity gives support for previously proposed flow–plume interactions: the primary cause of a 37 per cent variance in etch rate over a 72 per cent change in laminar flow velocity was a shift in the ratio between the refresh rate of liquid volume over the feature and laser repetition rate. The small variance of etch rate achieved by modification of turbulent regime flow velocity indicates that laser etching provided the dominating contribution to the total etch rate measured. This work demonstrates that this technique developed for ablation debris control does not reduce the efficiency of laser etching with respect to that achieved with established gas media laser ablation machining. Therefore, this process shows great promise for industrial implementation development