4,563 research outputs found
Total Mass-Momentum of Arbitrary Initial-Data Sets in General Relativity
For an asymptotically flat initial-data set in general relativity, the total
mass-momentum may be interpreted as a Hermitian quadratic form on the complex,
two-dimensional vector space of ``asymptotic spinors''. We obtain a
generalization to an arbitrary initial-data set. The mass-momentum is retained
as a Hermitian quadratic form, but the space of ``asymptotic spinors'' on which
it is a function is modified. Indeed, the dimension of this space may range
from zero to infinity, depending on the initial data. There is given a variety
of examples and general properties of this generalized mass-momentum.Comment: 25 pages, LaTe
The balance of payments adjustment process in Taiwan, Republic of China
Taiwan ; Balance of payments
The College and Career Experiences of Graduates of the College of Agriculture at Kansas State University 1978-1988
Teaching/Communication/Extension/Profession,
Some analysis on the diurnal variation of rainfall over the Atlantic Ocean
Data collected from the GARP Atlantic Tropical Experiment (GATE) was examined. The data were collected from 10,000 grid points arranged as a 100 x 100 array; each grid covered a 4 square km area. The amount of rainfall was measured every 15 minutes during the experiment periods using c-band radars. Two types of analyses were performed on the data: analysis of diurnal variation was done on each of grid points based on the rainfall averages at noon and at midnight, and time series analysis on selected grid points based on the hourly averages of rainfall. Since there are no known distribution model which best describes the rainfall amount, nonparametric methods were used to examine the diurnal variation. Kolmogorov-Smirnov test was used to test if the rainfalls at noon and at midnight have the same statistical distribution. Wilcoxon signed-rank test was used to test if the noon rainfall is heavier than, equal to, or lighter than the midnight rainfall. These tests were done on each of the 10,000 grid points at which the data are available
A case series of acquired haemophilia in a Malaysian hospital: unpredictabty rare medical emergency
Acquired haemophilia (AH) is a rare bleeding disorder characterized by the presence of acquired inhibitors against Factor VIII causing disruption of coagulation cascade. It has no known genetic inheritance, and diagnosis remains a challenge. The peculiar presentations are later age of onset as acute pain in weight-bearing joints and spontaneous muscle haematoma with isolated prolonged activated partial thrombin time (APTT). Prevalence is 1 per million per year affecting both genders equally where blood product transfusion is seen in almost 87% of cases. The direct cause of AH is still unknown, and autoimmune dysregulation has been postulated, which predisposes to the development of the factor inhibitors. Being extremely rare, we are reporting two consecutive patients diagnosed by unusual bleeding episodes with isolated prolonged APTT due to Factor VIII inhibitors. AH deserves a special mention as high index of suspicion is required. More studies are required to provide better guidance in diagnosis and management of this condition
Uncertainty and transparency:augmenting modelling and prediction for crisis response
Emergencies are characterised by uncertainty. This motivates the design of information systems that model and predict complex natural, material or human processes to support understanding and reduce uncertainty through prediction. The correspondence between system models and reality, however, is also governed by uncertainties, and designers have developed methods to render ‘the world’ transparent in ways that can inform, fine-tune and validate models. Additionally, people experience uncertainties in their use of simulation and prediction systems. This is a major obstacle to effective utilisation. We discuss ethically and socially motivated demands for transparency
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