1,008 research outputs found
Identification of economic and energy framework conditions of the Austrian climate and energy model regions
Fostering social learning through role-play simulations to operationalize comprehensive climate risk management: Insights from applying the RESPECT role-play in Austria
This paper describes an analytical-deliberative process, centered around the RESPECT role-play simulation, conducted to foster the operationalization of comprehensive climate risk management (CRM) in Lienz, southern Austria, a city that is representative of many alpine regions. We hypothesize that fostering social learning via participatory stakeholder engagement processes aids closing prevailing science–policy–implementation gaps in CRM, which are often a result from insufficiently clear roles and responsibilities, diverging stakeholder interests, priorities and risk perceptions, and inexistent or incipient cooperation mechanisms. To test this hypothesis, we co-developed and conducted a role-play simulation centered on riverine-flood risk—the most pressing climate-related risk in the Lienz case-study region. Based on our analysis of qualitative data gathered ex ante and ex post the intervention, we found role-play simulations to have a high potential for fostering social learning in CRM. After taking part, the diverse societal stakeholders were found to better understand: i) the interacting dimensions and drivers of riverine-flood risks; ii) the diverging risk perceptions; and iii) each other’s interests and needs in addressing such risks at the individual and institutional level. Role-play simulations are a promising transdisciplinary method for engaging societal stakeholders beyond traditional policy- and decision-making communities in informed and inclusive public debate around challenges and solutions to CRM. The methodological and practical insights gained in this Austrian case study may be transferred to the management of other climate-related risks
Sequence Effects on DNA Entropic Elasticity
DNA stretching experiments are usually interpreted using the worm-like chain
model; the persistence length A appearing in the model is then interpreted as
the elastic stiffness of the double helix. In fact the persistence length
obtained by this method is a combination of bend stiffness and intrinsic bend
effects reflecting sequence information, just as at zero stretching force. This
observation resolves the discrepancy between the value of A measured in these
experiments and the larger ``dynamic persistence length'' measured by other
means. On the other hand, the twist persistence length deduced from
torsionally-constrained stretching experiments suffers no such correction. Our
calculation is very simple and analytic; it applies to DNA and other polymers
with weak intrinsic disorder.Comment: LaTeX; postscript available at
http://dept.physics.upenn.edu/~nelson/index.shtm
Least-cost and 2 °C-compliant mitigation pathways robust to physical uncertainty, economic paradigms, and intergenerational cost distribution
Each run of an integrated assessment models produces a single mitigation pathway consistent with stated objectives (e.g. maximum temperature) and optimizing some objective function (e.g. minimizing total discounted costs of mitigation). Even though models can be run thousands of times, it is unclear how built-in assumptions constrain the final set of pathways. Here we aim at broadly exploring the space of possible mitigation scenarios for a given mitigation target, and at characterizing the sets of pathways that are (near-)optimal, taking uncertainties into account. We produce an extensive set of CO2 emission pathways that stay below 2 °C of warming using a reduced-form climate-carbon model with a 1000 different physical states. We then identify 18 sets of quasi 'least-cost' mitigation pathways, under six assumptions about cost functions and three different cost minimization functions embarking different visions of intergenerational cost distribution. A first key outcome is that the absence or presence of inertia in the cost function plays a pivotal role in the resulting set of least-cost pathways. Second, despite inherent structural differences, we find common pathways across the 18 combinations in 96% of the physical states studied. Interpreting these common pathways as robust economically and in terms of intergenerational distribution, we shed light on some of their characteristics, even though these robust pathways differ for each physical state
A parametric study of the acoustic properties of thermal cladding systems
Thermal cladding systems have developed and modernised since the first systems were implemented, and predictions of single figure sound insulation improvement, ΔRW, based on the natural frequency, f0, of the spring-mass covering may no longer be reliable. To identify aspects of the compound acoustic behaviour due to multiple power flow paths of the thermal insulating system, a statistical energy analysis (SEA) based prediction model was developed. A simplified calculation of sound insulation improvement, ΔR, is described, allowing the high frequency (f > f0) behaviour of thermal cladding systems to be predicted. A parametric study in which the impact of different construction materials in the model is discussed; the damping constants, elastic properties of the interlayer and fixings, number of fixings, thickness and material properties (including bending stiffness) of the weatherproof outer layer and the heavyweight wall are assessed. While agreement within 4.0 dB (mean absolute differences) between calculated and measured results for thick render (≥8.0 mm) and curtain wall systems can be obtained at high frequencies (f > f0) using the simplified methodology, this approach was not successful at predicting single figure values. This is because single figure values are weighted towards the low frequencies. Correlation of calculated f0 with measured ΔRW is slightly improved (r.m.s. differences of 2.62 compared with 3.21 using the f0 calculation methodology in EN ISO12354 Annex D) when a modified method to calculate the combined stiffness is used. To improve predictions further, a methodology must be developed to obtain the transfer function, Ytr, used to calculate non-resonant coupling loss factor due to the spring-mass resonance of thermal cladding on the heavyweight wall. The mobility of the connections, Yc, should also be accurately characterised to ensure accurate predictions at high frequencies
Conformations of closed DNA
We examine the conformations of a model for a short segment of closed DNA.
The molecule is represented as a cylindrically symmetric elastic rod with a
constraint corresponding to a specification of the linking number. We obtain
analytic expressions leading to the spatial configuration of a family of
solutions representing distortions that interpolate between the circular form
of DNA and a figure-eight form that represents the onset of interwinding. We
are also able to generate knotted loops. We suggest ways to use our approach to
produce other configurations relevant to studies of DNA structure. The
stability of the distorted configurations is assessed, along with the effects
of fluctuations on the free energy of the various configurations.Comment: 39 pages in REVTEX with 14 eps figures. Submitted to Phys. Rev. E.
This manuscript updates, expands and revises, to a considerable extent, a
previously posted manuscript, entitled "Conformations of Circular DNA," which
appeared as cond-mat/970104
Renovation and innovation using thermal insulation lining systems - Acoustic performance
Retrofit and design of thermal cladding systems provide an opportunity to improve the acoustic properties of a building. However, the complexity of the calculation process to predict sound insulation improvement may inhibit rather than encourage novelty and innovation. This paper investigates whether it is realistic to calculate the frequency dependant sound insulation improvement due to modern thermal insulation wall lining systems with just a few input parameters. The calculation procedure is tested using measured results for one external thermal insulation composite system (ETICS) and three curtain wall systems. The accuracy of the procedure is examined using three factors: (1) precision of the measurement, (2) variation of some of the basic parameters of the calculation procedure, and (3) an estimation of the standard error of the calculation. For the ETICS, agreement within <6.0 dB is achieved across much of the frequency range and the trend of the extended dip due to the spring-mass action of the panel is corroborated. The case for using this methodology on curtain wall systems is adequate, however, the trend of calculated results is mostly outside of the 95% confidence limits of the measured results. Possible reasons for this include lack of airtightness of all curtain wall systems and additional transmission due to radiation into and out of the cavity, neither of which are included in the model. The assumption of radiating points or lines, rather than a radiating surface involving the whole panel, gave better agreement at high frequencies for three of the four measured systems (f ≥ 2500 Hz)
Role of removals in contributing to the long-term goals of the Paris Agreement
This report delves into the multifaceted dimensions of carbon dioxide removal methods. The report discusses the role of carbon dioxide removal methods in contributing to attaining the long-term goal of the Paris Agreement and investigates best practices in the implementation of the collaborative instruments under Article 6 for their incentivisation and scaling. The present climate policy and actual decision-making are still centred on achieving net-zero carbon emissions but the long-term challenge is the inevitable reversal of the overshoot, requiring carbon removal to outpace residual emissions, leading to net negative emissions globally. The report discusses the need to assign responsibility for climate overshoot reversal in order to guarantee the viability of a global net-negative GHG economy. The report analyses and proposes ways to address risks associated with carbon removal, including mitigation deterrence, that carbon removed from the atmosphere might be re-released, carbon-leakage effects, and challenges related to monitoring mitigation outcomes. It offers recommendations based on these deliberations
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