2,848 research outputs found
An efficient sparse matrix multiplication scheme for the CYBER 205 computer
This paper describes the development of an efficient algorithm for computing the product of a matrix and vector on a CYBER 205 vector computer. The desire to provide software which allows the user to choose between the often conflicting goals of minimizing central processing unit (CPU) time or storage requirements has led to a diagonal-based algorithm in which one of four types of storage is selected for each diagonal. The candidate storage types employed were chosen to be efficient on the CYBER 205 for diagonals which have nonzero structure which is dense, moderately sparse, very sparse and short, or very sparse and long; however, for many densities, no diagonal type is most efficient with respect to both resource requirements, and a trade-off must be made. For each diagonal, an initialization subroutine estimates the CPU time and storage required for each storage type based on results from previously performed numerical experimentation. These requirements are adjusted by weights provided by the user which reflect the relative importance the user places on the two resources. The adjusted resource requirements are then compared to select the most efficient storage and computational scheme
Update on an Electromagnetic Basis for Inertia, Gravitation, the Principle of Equivalence, Spin and Particle Mass Ratios
A possible connection between the electromagnetic quantum vacuum and inertia
was first published by Haisch, Rueda and Puthoff (1994). If correct, this would
imply that mass may be an electromagnetic phenomenon and thus in principle
subject to modification, with possible technological implications for
propulsion. A multiyear NASA-funded study at the Lockheed Martin Advanced
Technology Center further developed this concept, resulting in an independent
theoretical validation of the fundamental approach (Rueda and Haisch, 1998ab).
Distortion of the quantum vacuum in accelerated reference frames results in a
force that appears to account for inertia. We have now shown that the same
effect occurs in a region of curved spacetime, thus elucidating the origin of
the principle of equivalence (Rueda, Haisch and Tung, 2001). A further
connection with general relativity has been drawn by Nickisch and Mollere
(2002): zero-point fluctuations give rise to spacetime micro-curvature effects
yielding a complementary perspective on the origin of inertia. Numerical
simulations of this effect demonstrate the manner in which a massless
fundamental particle, e.g. an electron, acquires inertial properties; this also
shows the apparent origin of particle spin along lines originally proposed by
Schroedinger. Finally, we suggest that the heavier leptons (muon and tau) may
be explainable as spatial-harmonic resonances of the (fundamental) electron.
They would carry the same overall charge, but with the charge now having
spatially lobed structure, each lobe of which would respond to higher frequency
components of the electromagnetic quantum vacuum, thereby increasing the
inertia and thus manifesting a heavier mass.Comment: 10 pages, 4 figures, AIP Conf. Proc., Space Technology and
Applications International Forum (STAIF-2003
Desain Media Pembelajaran Fisika Interaktif pada Materi Momen Inersia Benda Tegar dengan Menggunakan Program Autodesk 3ds Max 2010 dan Adobe Director 11.5
Penggunaan media dalam pembelajaran berfungsi untuk mempermudah penyampaian informasi, memvisualisasikan materi dengan baik, dan membuat pembelajaran menjadi lebih menarik. Fisika merupakan salah satu cabang dari Ilmu Pengetahuan Alam (IPA) yang materi-materi pembelajarannya berkaitan langsung dengan konteks kehidupan nyata. Oleh karena itu, diperlukan adanya media visual untuk memudahkan penyampaian materinya. Penelitian pengembangan ini bertujuan untuk mendesain dan menghasilkan media pembelajaran fisika interaktif pada materi momen inersia benda tegar dengan menggunakan program Autodesk 3ds Max 2010 dan Adobe Director 11.5. Penelitian ini dilaksanakan dalam tiga tahap yaitu tahap awal (studi pustaka, instalasi software, analisis), tahap pembuatan (pengumpulan konten, pengembangan, publish hasil), dan tahap evaluasi (penyesuaian kerangka konseptual, pencocokan materi, evaluasi, revisi, mengemas media pembelajaran). Berdasarkan hasil penelitian dapat disimpulkan program Autodesk 3ds Max 2010 dan Adobe Director 11.5 dapat digunakan untuk mendesain media pembelajaran fisika interaktif pada materi momen inersia benda tegar
German Prisoners of War in Maine, 1944-1946
Like many states during World War II, Maine faced a severe labor shortage at a time when wartime needs boosted production demands. Northern Maine farmers and paper makers used German prisoners of war to help meet these extraordinary demands. Despite early apprehensions among local people, the POW\u27s, stationed in Houlton, remained unobtrusive. They responded well to the rigors of climate and work, and some of them formed lasting friendships with local residents
A study of hybridization and behavioral characters in Percina notogramma (Rany and Hubbs) and Percina peltata (Stauffer), family Percidae
In view of the close phylogenetic relationship between the two symÂpatric species of darters, Percina notogramma (Raney and Hubbs) and Percina peltata (Stauffer), placed in the subgenus Alvordius by Bailey and Gosline (1955), it is of interest to compare them in more detail than has been done in the past. Percina notograrnma occurs only in the Chesapeake Drainage in Virginia, Maryland and West Virginia whereas P. peltata ranges from Virginia to New York. Adequate comparisons of their external. morphological characters have been presented by Raney and Hubbs (1948) in their original description of P. notogramma. Supplementary data were provided by Hogarth and Woolcott (1966) in a paper describing the subspecies, P. n. montuosa, from the James River. In the present study, some observations indicating introgressive hybridization and others on behavioral characters will be followed by an attempt to integrate the evidence each provides concerning the phylogenetic relationship of the two species
Barriers to Succession Planning: A Case Study of Atlanta Nonprofit Organizations
Succession planning is not a common practice among nonprofit organizations, despite support for its effectiveness in supporting leadership development and providing organizational stability during a planned or unplanned transition. Nonprofits have acknowledged that their leadership ranks are thin, and a leadership transition tends to bring challenges to the organizations when vacancies need to be filled. Barriers exist that prevent nonprofits from engaging in succession planning, but little research has examined the nature of these barriers. This study focused on nonprofit organizations across four different industry sectors to determine the extent of their succession planning efforts and the barriers that exist that hinder the implementation of succession planning. I used a qualitative, multiple-case study approach and conducted 20 semistructured interviews comprised of a sample of organizational leaders with knowledge of their organizations’ succession planning activities. The study produced five themes discussing 1) the extent of succession planning activities in nonprofit organizations (NPOs); 2) succession planning in the hierarchy of organizational focus and priorities; 3) how succession planning relates to organizational survival; 4) how NPOs maintain organizational stability; and 5) if succession planning is an essential or good practice for NPOs. The implications of the study show that the practice of succession planning, while a viable option for long-term stability, does not fit all organizational models or needs and NPOs have alternative methods to meet their needs when leadership positions become vacant
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The association of Lophodermium pinastri with the eastern white pine and Scots pine.
Thesis (M.S.
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