164 research outputs found
The integrable hierarchy constructed from a pair of KdV-type hierarchies and its associated algebra
For any two arbitrary positive integers `' and `', using the --th
KdV hierarchy and the --th KdV hierarchy as building blocks, we are able
to construct another integrable hierarchy (referred to as the --th KdV
hierarchy). The --algebra associated to the \shs\, of the --th KdV
hierarchy (called algebra) is isomorphic via a Miura map to the direct
sum of --algebra, --algebra and an additional current
algebra. In turn, from the latter, we can always construct a representation of
--algebra.Comment: 26p, latex, BONN--TH-94-17, SISSA-ISAS-118/94/EP, AS-ITP-94-43,
revised version with addition
Testing effort dependent software reliability model for imperfect debugging process considering both detection and correction
This paper studies the fault detection process (FDP) and fault correction process (FCP) with the incorporation of testing effort function and imperfect debugging. In order to ensure high reliability, it is essential for software to undergo a testing phase, during which faults can be detected and corrected by debuggers. The testing resource allocation during this phase, which is usually depicted by the testing effort function, considerably influences not only the fault detection rate but also the time to correct a detected fault. In addition, testing is usually far from perfect such that new faults may be introduced. In this paper, we first show how to incorporate testing effort function and fault introduction into FDP and then develop FCP as delayed FDP with a correction effort. Various specific paired FDP and FCP models are obtained based on different assumptions of fault introduction and correction effort. An illustrative example is presented. The optimal release policy under different criteria is also discussed
Inelastic Rescattering and CP Asymmetries in D -> pi+ pi-, pi0 pi0
We study the direct CP violation induced by inelastic final state interaction
(FSI) rescattering in modes, and find that the resultant CP
asymmetry is about which is larger than in the K-system.
Our estimation is based on well-established theories and experiment measured
data, so there are almost no free parameters except the weak phase
in the CKM matrix.Comment: 9 page
Mapping geographical inequalities in childhood diarrhoeal morbidity and mortality in low-income and middle-income countries, 2000–17 : analysis for the Global Burden of Disease Study 2017
Background
Across low-income and middle-income countries (LMICs), one in ten deaths in children younger than 5 years is attributable to diarrhoea. The substantial between-country variation in both diarrhoea incidence and mortality is attributable to interventions that protect children, prevent infection, and treat disease. Identifying subnational regions with the highest burden and mapping associated risk factors can aid in reducing preventable childhood diarrhoea.
Methods
We used Bayesian model-based geostatistics and a geolocated dataset comprising 15 072 746 children younger than 5 years from 466 surveys in 94 LMICs, in combination with findings of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017, to estimate posterior distributions of diarrhoea prevalence, incidence, and mortality from 2000 to 2017. From these data, we estimated the burden of diarrhoea at varying subnational levels (termed units) by spatially aggregating draws, and we investigated the drivers of subnational patterns by creating aggregated risk factor estimates.
Findings
The greatest declines in diarrhoeal mortality were seen in south and southeast Asia and South America, where 54·0% (95% uncertainty interval [UI] 38·1–65·8), 17·4% (7·7–28·4), and 59·5% (34·2–86·9) of units, respectively, recorded decreases in deaths from diarrhoea greater than 10%. Although children in much of Africa remain at high risk of death due to diarrhoea, regions with the most deaths were outside Africa, with the highest mortality units located in Pakistan. Indonesia showed the greatest within-country geographical inequality; some regions had mortality rates nearly four times the average country rate. Reductions in mortality were correlated to improvements in water, sanitation, and hygiene (WASH) or reductions in child growth failure (CGF). Similarly, most high-risk areas had poor WASH, high CGF, or low oral rehydration therapy coverage.
Interpretation
By co-analysing geospatial trends in diarrhoeal burden and its key risk factors, we could assess candidate drivers of subnational death reduction. Further, by doing a counterfactual analysis of the remaining disease burden using key risk factors, we identified potential intervention strategies for vulnerable populations. In view of the demands for limited resources in LMICs, accurately quantifying the burden of diarrhoea and its drivers is important for precision public health
Hypoxic Pulmonary Vasoconstriction in Humans:Tale or Myth
Hypoxic Pulmonary vasoconstriction (HPV) describes the physiological adaptive process of lungs to preserves systemic oxygenation. It has clinical implications in the development of pulmonary hypertension which impacts on outcomes of patients undergoing cardiothoracic surgery. This review examines both acute and chronic hypoxic vasoconstriction focusing on the distinct clinical implications and highlights the role of calcium and mitochondria in acute versus the role of reactive oxygen species and Rho GTPases in chronic HPV. Furthermore it identifies gaps of knowledge and need for further research in humans to clearly define this phenomenon and the underlying mechanism
A study of software fault detection and correction process models
10.1109/ICMIT.2006.262333ICMIT 2006 Proceedings - 2006 IEEE International Conference on Management of Innovation and Technology2812-81
Spin rotator and shot noise in graphene-based multi-barrier nanostructure
Based on the transfer-matrix method, the spin transport properties through a
graphene-based multi-barrier nanostructure with an exchange field and Rashba spin orbit
coupling (SOC), have been investigated. It is found that if Rashba SOC equals to the
exchange field, the multi-barrier nanostructure is an efficient way to achieve spin
rotators and spin filters. In addition, it is also found that the shot noise of a spin
state can be enhanced by electrostatic potential, and plateaus of the Fano factor is
formed
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