History Shows (history + shows)

Distribution by Scientific Domains


Selected Abstracts


Organizational evolution of digital signal processing software development

JOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 4 2006
Susanna Pantsar-Syväniemi
Abstract A base station, as a network element, has become an increasingly software-intensive system. Digital signal processing (DSP) software is hard real-time software that is a part of the software system needed in a base station. This article reports practical experiences related to organizing the development of embedded software in the telecommunication industry, at Nokia Networks. The article introduces the main factors influencing the development of DSP software and also compares the evolutionary process under study with both selected organizational models for a software product line and a multistage model for the software life cycle. We believe it is vitally important to formulate the organization according to the software architecture, and it is essential to have a dedicated development organization with long-term responsibility for the software. History shows that without long-term responsibility, there is no software reuse. In this paper we introduce a new organizational model for product line development. This new hybrid model clarifies long-term responsibilities in large software organizations with hundreds of staff members and formulates the organization according to the software architecture. Our case needs a couple more constraints to keep it in the evolution stage of the software life cycle. Thus, we extend the evolution phase in the multistage model to make it relevant for embedded, hard real-time software. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Parallel simulation of unsteady hovering rotor wakes

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 6 2006
C. B. Allen
Abstract Numerical simulation using low diffusion schemes, for example free-vortex or vorticity transport methods, and theoretical stability analyses have shown the wakes of rotors in hover to be unsteady. This has also been observed in experiments, although the instabilities are not always repeatable. Hovering rotor wake stability is considered here using a finite-volume compressible CFD code. An implicit unsteady, multiblock, multigrid, upwind solver, and structured multiblock grid generator are presented, and applied to lifting rotors in hover. To allow the use of very fine meshes and, hence, better representation of the flow physics, a parallel version of the code has been developed, and parallel performance using upto 1024 CPUs is presented. A four-bladed rotor is considered, and it is demonstrated that once the grid density is sufficient to capture enough turns of the tip vortices, hover exhibits oscillatory behaviour of the wake, even using a steady formulation. An unsteady simulation is then performed, and also shows an unsteady wake. Detailed analysis of the time-accurate wake history shows that three dominant unsteady modes are captured, for this four-bladed case, with frequencies of one, four, and eight times the rotational frequency. A comparison with theoretical stability analysis is also presented. Copyright © 2006 John Wiley & Sons, Ltd. [source]


An analysis of the demarcation problem in science and its application to therapeutic touch theory

INTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 6 2007
David Newbold RN PhD
This paper analyses the demarcation problem from the perspective of four philosophers: Popper, Kuhn, Lakatos and Feyerabend. To Popper, pseudoscience uses induction to generate theories, and only performs experiments to seek to verify them. To Popper, falsifiability is what determines the scientific status of a theory. Taking a historical approach, Kuhn observed that scientists did not follow Popper's rule, and might ignore falsifying data, unless overwhelming. To Kuhn, puzzle-solving within a paradigm is science. Lakatos attempted to resolve this debate, by suggesting history shows that science occurs in research programmes, competing according to how progressive they are. The leading idea of a programme could evolve, driven by its heuristic to make predictions that can be supported by evidence. Feyerabend claimed that Lakatos was selective in his examples, and the whole history of science shows there is no universal rule of scientific method, and imposing one on the scientific community impedes progress. These positions are used in turn, to examine the scientific status of therapeutic touch theory. The paper concludes that imposing a single rule of method can impede progress, in the face of multiple epistemologies, and the choice of scientific approach should be a pragmatic one based on the aims of the programme. [source]


The Perils of Cognitive Enhancement and the Urgent Imperative to Enhance the Moral Character of Humanity

JOURNAL OF APPLIED PHILOSOPHY, Issue 3 2008
INGMAR PERSSON
abstract As history shows, some human beings are capable of acting very immorally.1 Technological advance and consequent exponential growth in cognitive power means that even rare evil individuals can act with catastrophic effect. The advance of science makes biological, nuclear and other weapons of mass destruction easier and easier to fabricate and, thus, increases the probability that they will come into the hands of small terrorist groups and deranged individuals. Cognitive enhancement by means of drugs, implants and biological (including genetic) interventions could thus accelerate the advance of science, or its application, and so increase the risk of the development or misuse of weapons of mass destruction. We argue that this is a reason which speaks against the desirability of cognitive enhancement, and the consequent speedier growth of knowledge, if it is not accompanied by an extensive moral enhancement of humankind. We review the possibilities for moral enhancement by biomedical and genetic means and conclude that, though it should be possible in principle, it is in practice probably distant. There is thus a reason not to support cognitive enhancement in the foreseeable future. However, we grant that there are also reasons in its favour, but we do not attempt to settle the balance between these reasons for and against. Rather, we conclude that if research into cognitive enhancement continues, as it is likely to, it must be accompanied by research into moral enhancement. [source]


Exhumation during oblique transpression: The Feiran,Solaf region, Egypt

JOURNAL OF METAMORPHIC GEOLOGY, Issue 6 2009
T. S. ABU-ALAM
Abstract The Feiran,Solaf metamorphic complex of Sinai, Egypt, is one of the highest grade metamorphic complexes of a series of basement domes that crop out throughout the Arabian-Nubian Shield. In the Eastern Desert of Egypt these basement domes have been interpreted as metamorphic core complexes exhumed in extensional settings. For the Feiran,Solaf complex an interpretation of the exhumation mechanism is difficult to obtain with structural arguments as all of its margins are obliterated by post-tectonic granites. Here, metamorphic methods are used to investigate its tectonic history and show that the complex was characterized by a single metamorphic cycle experiencing peak metamorphism at ,700,750 °C and 7,8 kbar and subsequent isothermal decompression to ,4,5 kbar, followed by near isobaric cooling to 450 °C. Correlation of this metamorphic evolution with the deformation history shows that peak metamorphism occurred prior to the compressive deformation phase D2, while the compressive D2 and D3 deformation occurred during the near isothermal decompression phase of the P,T loop. We interpret the concurrence of decompression of the P,T path and compression by structural shortening as evidence for the Najd fault system exhuming the complex in an oblique transpressive regime. However, final exhumation from ,15 km depth must have occurred due to an unrelated mechanism. [source]


The individual and "the general situation": The tension barometer and the race problem at the University of Chicago, 1947,1954

JOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES, Issue 1 2010
Leah N. Gordon
This article explains how social theories that posited white attitudes as the root of racial injustice gained traction in postwar social thought. Examining the production of a "tension barometer," an attitude survey that scholars from the University of Chicago's Committee on Education, Training, and Research in Race Relations created to predict interracial violence, I chart vigorous debate over the nature and causes of racial oppression in the critical postwar decades. Available,and unavailable,social scientific frameworks, activists" interests, and emerging anticommunism, the Committee's history shows, created an environment where individualistic conceptions of the race problem won out, despite critique. © 2010 Wiley Periodicals, Inc. [source]


RELIGIOUS CULTURE AND HISTORICAL CHANGE: VATICAN II ON RELIGIOUS FREEDOM

THE HEYTHROP JOURNAL, Issue 5 2008
M. JOHN FARRELLY O.S.B.
At Vatican II and since Vatican II there have been Catholics who have held that the Council's teaching on religious freedom is in contradiction to the Church's earlier teaching and practice. The Council defended it as a legitimate development of doctrine in part through claiming that changing human experience in history shows us only gradually what human dignity entails, and the Church learns from this experience. True, the Council's teaching is in part a denial of its earlier teaching and practice. The present article defends the legitimacy of this development through showing that there is a change of paradigm by which the Church now views this issue, a change that includes both continuity and discontinuity. This reliance on what is revealed to us by changing human experience is accepted by the Church only when it sees it as critically evaluated by an adequate philosophy and as in accord with Christian revelation, but its acceptance moves us to a growth in our understanding of revelation itself. [source]


Carbonate sedimentation in a starved pull-apart basin, Middle to Late Devonian, southern Guilin, South China

BASIN RESEARCH, Issue 2 2001
D. Chen
ABSTRACT Geological mapping and sedimentological investigations in the Guilin region, South China, have revealed a spindle- to rhomb-shaped basin filled with Devonian shallow- to deep-water carbonates. This Yangshuo Basin is interpreted as a pull-apart basin created through secondary, synthetic strike-slip faulting induced by major NNE,SSW-trending, sinistral strike-slip fault zones. These fault zones were initially reactivated along intracontinental basement faults in the course of northward migration of the South China continent. The nearly N,S-trending margins of the Yangshuo Basin, approximately coinciding with the strike of regional fault zones, were related to the master strike-slip faults; the NW,SE-trending margins were related to parallel, oblique-slip extensional faults. Nine depositional sequences recognized in Givetian through Frasnian strata can be grouped into three sequence sets (Sequences 1,2, 3,5 and 6,9), reflecting three major phases of basin evolution. During basin nucleation, most basin margins were dominated by stromatoporoid biostromes and bioherms, upon a low-gradient shelf. Only at the steep, fault-controlled, eastern margin were thick stromatoporoid reefs developed. The subsequent progressive offset and pull-apart of the master strike-slip faults during the late Givetian intensified the differential subsidence and produced a spindle-shaped basin. The accelerated subsidence of the basin centre led to sediment starvation, reduced current circulation and increased environmental stress, leading to the extensive development of microbial buildups on platform margins and laminites in the basin centre. Stromatoporoid reefs only survived along the windward, eastern margin for a short time. The architectures of the basin margins varied from aggradation (or slightly backstepping) in windward positions (eastern and northern margins) to moderate progradation in leeward positions. A relay ramp was present in the north-west corner between the northern oblique fault zone and the proximal part of the western master fault. In the latest Givetian (corresponding to the top of Sequence 5), a sudden subsidence of the basin induced by further offset of the strike-slip faults was accompanied by the rapid uplift of surrounding carbonate platforms, causing considerable platform-margin collapse, slope erosion, basin deepening and the demise of the microbialites. Afterwards, stromatoporoid reefs were only locally restored on topographic highs along the windward margin. However, a subsequent, more intense basin subsidence in the early Frasnian (top of Sequence 6), which was accompanied by a further sharp uplift of platforms, caused more profound slope erosion and platform backstepping. Poor circulation and oxygen-depleted waters in the now much deeper basin centre led to the deposition of chert, with silica supplied by hydrothermal fluids through deep-seated faults. Two ,subdeeps' were diagonally arranged in the distal parts of the master faults, and the relay ramp was destroyed. At this time, all basin margins except the western one evolved into erosional types with gullies through which granular platform sediments were transported by gravity flows to the basin. This situation persisted into the latest Frasnian. This case history shows that the carbonate platform architecture and evolution in a pull-apart basin were not only strongly controlled by the tectonic activity, but also influenced by the oceanographic setting (i.e. windward vs. leeward) and environmental factors. [source]