24,401 research outputs found
History of vertical displacement of Kerepehi Fault at Kopouatai bog, Hauraki Lowlands, New Zealand, since c. 10 700 years ago
Thirteen tephra layers interbedded with peat, and a basal peathorizon, in four pairs of cores provide radiocarbon-dated reference horizons that indicate vertical displacement on the Kerepehi Fault at Kopouatai bog, Hauraki Lowlands. Progressive offset of the horizons with time shows that vertical fault movement, downthrown to the west, has been occurring for the past c. 10 700 radiocarbon years at an approximately uniform rate of c. 0.13 mm/yr. Step functions indicate faulting events earthquakes at c. 1400, c. 5600, c. 6800, and C. 9000 years ago, a mean recurrence interval of c. 2500 years. These findings support geophysical and geological evidence that the Hauraki Depression is an active rift, and show that active faulting occurs along the northern as well as southern extensions of the Kerepehi Fault.
If such earthquakes occur randomly in time, and based on the return period of 2500 years, there are 2%, 18%, and 33% probabilities of a major earthquake affecting the Kerepehi Fault at Kopouatai bog in the next 50, 500, and 1000 years, respectively
Influence of intensity distribution on the meltpool and clad shape for laser cladding
The influence of the optical system on the laser cladding process is studied, in particular with respect to the burn-in shape: the penetration of the meltpool into the substrate. The beam caustic and intensity profiles for the commonly used out-of-focus laser clad operation are presented and discussed. To avoid the disadvantages of the out-of-focus operation, a novel telezoom optical system is developed, which allows in-focus operation with a sufficiently large focus with a uniform intensity distribution and a spot diameter ranging from 3 up to over 6 mm. Different typical burn-in shapes are indicated, as they can be found in cross sections of experimental clads. The influence of the intensity distribution on the occurring burn-in shapes is discussed, as well as other phenomena that can play a role, such as flow recirculation cells in the meltpool
Opportunistic behaviour by private irrigators within a capacity-sharing regime
The concept of capacity-sharing (as a specific type of demand-orientated water management strategy) is a relatively newcomer on the South African water management regime and much debate is currently under way regarding the viability of the concept for the South African context. One of the main features is that it decentralises and integrates water management to a much greater degree than state-dominated management regimes. However, as the concept of capacity-sharing allows a greater degree of decision-making autonomy to the private decision-maker, the question could be asked to what extent the management of a capacity-sharing regime would be exposed to opportunistic behaviour from private irrigators. If it is heavily exposed, there are considerable scope for opportunistic decision-making behaviour under private decision-makers and therefore problems of moral hazard / adverse selection and rent seeking could present itself. Therefore, the question arises what safety features do capacity sharing present to confine possible opportunistic decision-making practices. This article discusses two areas within a capacity-sharing regime that are likely to be exposed to opportunistic decision-making behaviour. Possible safety-features from capacity sharing to account for this type of behaviour are identified and discussed briefly. This article concludes with the notion that capacity sharing does feature some properties that could minimise opportunistic behaviour from private decision-makers.Resource /Energy Economics and Policy,
Towards more inclusive long-term bulk water resource management
Fresh water resources provide a platform for complex and often emotional issues to develop, particularly in resource scarcity situations. Bulk water infrastructure contains elements of a public good and proved vulnerable to failures in market and government driven allocation strategies. Common to both are uncaptured costs and benefits due to shortcomings in cost quantification techniques. Natural ecosystems stands to lose the most since ecosystem services are often not quantifiable in monetary terms and therefore neglected in allocation decision-making. This paper took on the challenge of expanding current decision-support in order to promote more inclusive long-term water management. A case-study approach with the focus on a choice related problem regarding different long-term bulk water resource management options was applied in the Western Cape province. The paper incorporated components of economic valuation theory, a public survey and a modified Delphi expert panel technique. Both spatial and temporal dimensions of the decision-making context were expanded. Two surveys were completed to accommodate these expansions. The first focused on public preference in water allocation management and the relative merit of accommodating public preference in highly specialised decision-making such as long-term water allocation decision-making. The second survey utilized a modified Delphi technique in which an expert panel indicated the relative merit of two alternative long-term allocation strategies. A willingness to pay for 'greener' water was observed and may be used to motivate a paradigm shift from management's perspective to consider, without fear of harming their own political position, 'greener' water supply options more seriously even if these options imply higher direct costs to public.water management, decision-support, public participation, Resource /Energy Economics and Policy,
Geometric models for Lie--Hamilton systems on
This paper provides a geometric description for Lie--Hamilton systems on
with locally transitive Vessiot--Guldberg Lie algebras through
two types of geometric models. The first one is the restriction of a class of
Lie--Hamilton systems on the dual of a Lie algebra to even-dimensional
symplectic leaves relative to the Kirillov-Kostant-Souriau bracket. The second
is a projection onto a quotient space of an automorphic Lie--Hamilton system
relative to a naturally defined Poisson structure or, more generally, an
automorphic Lie system with a compatible bivector field. These models give rise
to a natural framework for the analysis of Lie--Hamilton systems on
while retrieving known results in a natural manner. Our methods
may be extended to study Lie--Hamilton systems on higher-dimensional manifolds
and provide new approaches to Lie systems admitting compatible geometric
structures.Comment: 15 pages, 1 figur
Entanglement genesis by ancilla-based parity measurement in 2D circuit QED
We present an indirect two-qubit parity meter in planar circuit quantum
electrodynamics, realized by discrete interaction with an ancilla and a
subsequent projective ancilla measurement with a dedicated, dispersively
coupled resonator. Quantum process tomography and successful entanglement by
measurement demonstrate that the meter is intrinsically quantum non-demolition.
Separate interaction and measurement steps allow commencing subsequent data
qubit operations in parallel with ancilla measurement, offering time savings
over continuous schemes.Comment: 5 pages, 4 figures; supplemental material with 5 figure
Sensitivity to social exclusion in major depressive disorder (MDD) predicts therapeutic outcome after in-patient treatment
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De schijnwerkelijkheid van gezamenlijke besluitvorming
Het nemen van besluiten lijkt inherent te zijn aan ziek zijn. Steeds vaker wordt er van de patiënt verwacht dat hij zelf gaat kiezen en eigen regie voert. De patiënt weet immers zelf wat het beste voor hem is, is de gedachte. Gezamenlijke besluitvorming lijkt hierin een welkom concept om te komen tot goede zorg. Maar is dit wel het geval?
Door middel van zorgethisch onderzoek is er inzicht verworven in de ervaringen van twee patiënten, en diens naasten, waar besluiten worden gevormd omtrent behandeling op het moment dat er sprake is van ziekte. Er zijn twee fenomenologische casestudies uitgevoerd om antwoord te kunnen geven op de hoofdvraag: Hoe ervaren mensen met uitgezaaide, ongeneeslijke kanker de besluitvorming omtrent behandeling en wat is voor hen daarin goede zorg?
Vanuit de verworven data worden vijf thema’s gedestilleerd: vervreemding van het vertrouwde, ervaring van chaos, hoop, gezien worden en samen ziek zijn. Te zien is dat deze thema’s samen een membraan vormen waarin de patiënt terecht komt. Binnen dit membraan worden geen rationele keuzes gemaakt, iets wat het concept van gezamenlijke besluitvorming binnen de dominante literatuur wel verondersteld. De vooronderstelde werkelijkheid sluit niet aan bij de echte werkelijkheid met een schijnwerkelijkheid tot gevolg. De dominante opvatting van gezamenlijke besluitvorming sluit dan ook niet aan bij de wereld van de patiënten en laat patiënten juist alleen in deze onvertrouwde en onveilige situatie. Dit onderzoek laat zien dat goed zorgen meer is dan kiezen en het nemen van besluiten. Er zal vanuit een relationeel mensbeeld aansluiting moeten worden gevonden bij de aspecten van afhankelijkheid en kwetsbaarheid die inherent zijn aan het menselijk bestaan, juist ook op het moment van ziekte. Die kwetsbaarheid en afhankelijkheid spelen een belangrijke rol in de vorming van besluiten en de strubbelingen en opgaven waar patiënten voor komen te staan
Set-up effects of piles in sand tested in the centrifuge
The bearing capacity of piles increases over time. Research has shown that this is caused by an increase in shaft friction combined with a constant or only slightly increasing base capacity. Although there are some ideas on the mechanisms that play a role there is no quantitative model to describe this mechanism. From the literature the shaft friction seems to increase linearly with the logarithm of time. For piles in the field this is proven by load tests performed between 1 until approximately 1000 days after installation. Literature indicates that set-up as a function of time is also present minutes and hours after installation. This allows investigating the set-up mechanisms under controlled conditions in a centrifuge. Therefore two test series have been performed to investigate the set-up for a single pile and a pile group. This paper presents the relevant literature and describes the position of the tests in the on-going research program on piles in The Netherlands. Furthermore, the results will be described and discussed. Time dependency in bearing capacity in sand can be observed in the centrifuge tests, although it is not certain whether some of the increase has not been caused by other mechanisms. It appears that the testing conditions as well as the effects of installation of neighboring piles are of great importance on the time effects
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