960 research outputs found

    Towards the development of an integrated sustainability and resilience benefits assessment framework of urban green growth interventions

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    Considering the current emerging demographic, urbanization and climatic trends, integrating sustainability and resilience principles into urban development becomes a key priority for decision-makers worldwide. Local and national governments, project developers and other urban stakeholders dealing with the complexities of urban development need projects with clear structure and outcomes in order to inform decision-making and ensure sources of financing. The need for developing an integrated assessment methodology that would capture and quantify multiple urban sustainability and resilience benefits of projects in one common framework and eventually lead to verifiable sustainability and resilience outcomes is immense and challenging at the same time. The main objective of this paper is to present the development of a methodological approach that aims to integrate sustainability and resilience benefits, derived from the implementation of green growth urban projects, into a unified framework of criteria addressing environmental, social, economic and institutional perspectives. The proposed sustainability and resilience benefits assessment (SRBA) methodology is a combination of top down and bottom up approaches, including GIS-based scenario building. The different types of sustainability and resilience benefits of urban green growth projects are also identified at different levels (i.e., individual, neighborhood, city and global). Moreover, the proposed methodology creates scenarios that can be illustrated by a map-based approach to enable a better illustration and visualization of benefits. It demonstrates how a map-based approach can assess not only the extent of sustainability and resilience benefits accrued (how much is benefitted), but also their spatial distribution (who is benefitted). The main methodological challenges and issues on developing an integrated sustainability and resilience benefits assessment are identified and discussed

    Optimal slice thickness for object detection with longitudinal partial volume effects in computed tomography.

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    Longitudinal partial volume effects (z-axial PVE), which occur when an object partly occupies a slice, degrade image resolution and contrast in computed tomography (CT). Z-axial PVE is unavoidable for subslice objects and reduces their contrast according to their fraction contained within the slice. This effect can be countered using a smaller slice thickness, but at the cost of an increased image noise or radiation dose. The aim of this study is to offer a tool for optimizing the reconstruction parameters (slice thickness and slice spacing) in CT protocols in the case of partial volume effects. This optimization is based on the tradeoff between axial resolution and noise. For that purpose, we developed a simplified analytical model investigating the average statistical effect of z-axial PVE on contrast and contrast-to-noise ratio (CNR). A Catphan 500 phantom was scanned with various pitches and CTDI and reconstructed with different slice thicknesses to assess the visibility of subslice targets that simulate low contrast anatomical features present in CT exams. The detectability score of human observers was used to rank the perceptual image quality against the CNR. Contrast and CNR reduction due to z-axial PVE measured on experimental data were first compared to numerical calculations and then to the analytical model. Compared to numerical calculations, the simplified algebraic model slightly overestimated the contrast but the differences remained below 5%. It could determine the optimal reconstruction parameters that maximize the objects visibility for a given dose in the case of z-axial PVE. An optimal slice thickness equal to three-fourth of the object width was correctly proposed by the model for nonoverlapping slices. The tradeoff between detectability and dose is maximized for a slice spacing of half the slice thickness associated with a slice width equal to the characteristic object width

    Coming to Financial Close in PPPs: Identifying Critical Factors in the Case of Toll Road Projects in Indonesia

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    In Indonesia, public–private partnerships (PPPs) schemes have been attracting a lot of attention to meet the huge demand for infrastructure developments. However, their applications are still limited and the financial close of a project tends to be behind the planned schedule. This research therefore aims to investigate the critical success factors (CSFs) causing fast/slow progress in the processes toward the financial close of PPPs toll road projects in Indonesia. The results revealed that, to realize smoother delivery of PPPs toll road projects in Indonesia to the financial close in the future, it is important to improve coordination among the related stakeholders especially between the central and local governments, though the other CSFs are currently well developed. The research also found an issue that should be addressed from a sustainability viewpoint, namely that the government highly depends on state-owned companies (SOEs) for a timely financial close of PPPs toll road projects

    Smart energy transition: An evaluation of cities in South Korea

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    One positive impact of smart cities is reducing energy consumption and CO2 emission through the use of information and communication technologies (ICT). Energy transition pursues systematic changes to the low-carbon society, and it can benefit from technological and institutional advancement in smart cities. The integration of the energy transition to smart city development has not been thoroughly studied yet. The purpose of this study is to find empirical evidence of smart cities' contributions to energy transition. The hypothesis is that there is a significant difference between smart and non-smart cities in the performance of energy transition. The Smart Energy Transition Index is introduced. Index is useful to summarize the smart city component's contribution to energy transition and to enable comparison among cities. The cities in South Korea are divided into three groups: (1) first-wave smart cities that focus on smart transportation and security services; (2) second-wave smart cities that provide comprehensive urban services; and (3) non-smart cities. The results showed that second-wave smart cities scored higher than first-wave and non-smart cities, and there is a statistically significant difference among city groups. This confirms the hypothesis of this p

    A Sustainable Approach to Innovation Adoption in Light-rail Transport

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    This article primary aims to understand how the Light-Rail Transport (LRT) pricing and infrastructural innovations from a Chinese context have been adopted to the Addis-Ababa city context. Secondly, it wishes to show what were the economic, social and environmental effects of these adapted innovations on passenger service delivery and Multi-National Corporations (MNCs) and what effects did the resident’s proximity have on commercial activities along the LRT route. Thirdly, it identified re-adaptations to a more sustainable LRT with respect to the passengers, MNCs, and residents. This study has revealed economic, social and environmental effects that may influence innovation adoption, such as: reduction in carbon emissions; fare evasion; inconvenience; affordability; less revenue; less proximity to commercial activities; and an increase in travel distances for pedestrians. A mixed method for a single case study was used, which included semi-structured interviews with light-rail experts and a passenger survey. The results show that economic sustainability factors account for 12 out of 14 sustainability factors and 2 out of 14 social and environmental sustainability factors. The results are intended to be used as a decision support system for innovation adoption in other cities with similar context, in order to develop a sustainable approach to LRT planning

    Fast adaptation of cooperative channels engenders Hopf bifurcations in auditory hair cells

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    Since the pioneering work of Thomas Gold, published in 1948, it has been known that we owe our sensitive sense of hearing to a process in the inner ear that can amplify incident sounds on a cycle-by-cycle basis. Called the active process, it uses energy to counteract the viscous dissipation associated with sound-evoked vibrations of the ear’s mechanotransduction apparatus. Despite its importance, the mechanism of the active process and the proximate source of energy that powers it have remained elusive, especially at the high frequencies characteristic of amniote hearing. This is partly due to our insufficient understanding of the mechanotransduction process in hair cells, the sensory receptors and amplifiers of the inner ear. It has been proposed previously that cyclical binding of Ca2+ ions to individual mechanotransduction channels could power the active process. That model, however, relied on tailored reaction rates that structurally forced the direction of the cycle. Here we ground our study on our previous model of hair-cell mechanotransduction, which relied on cooperative gating of pairs of channels, and incorporate into it the cyclical binding of Ca2+ ions. With a single binding site per channel and reaction rates drawn from thermodynamic principles, the current model shows that hair cells behave as nonlinear oscillators that exhibit Hopf bifurcations, dynamical instabilities long understood to be signatures of the active process. Using realistic parameter values, we find bifurcations at frequencies in the kilohertz range with physiological Ca2+ concentrations. The current model relies on the electrochemical gradient of Ca2+ as the only energy source for the active process and on the relative motion of cooperative channels within the stereociliary membrane as the sole mechanical driver. Equipped with these two mechanisms, a hair bundle proves capable of operating at frequencies in the kilohertz range, characteristic of amniote hearing

    Interactions among three species of cereal aphids simultaneously infesting wheat

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    Interactions among greenbug, Schizaphis graminum (Rondani), Russian wheat aphid, Diuraphis noxia (Mordvilko), and bird cherry-oat aphid Rhopalosiphum padi (L.) were examined on wheat plants (Triticum aestivum L., cultivar TAM 107). Nymphs were released on the plants as conspecific and heterospecific pairs of either first or fourth instars and evaluated for survival, developmental time, fecundity, intra-plant movement, and affinity to plant tissues. Survival from first instar to onset of reproduction averaged 90–100% across all pair combinations. Diuraphis noxia developed faster as conspecifics than in any heterospecific combination, and faster as conspecifics feeding on the same plant tissue than on different tissues. Fecundity of S. graminum was higher for conspecifics that developed on the same plant tissue than for those feeding separately. There was evidence of amensalism (one species was harmed while the other was unaffected) in that D. noxia experienced delayed development feeding in tandem with S. graminum, and reduced fecundity with both S. graminum and R. padi. Furthermore, S. graminum nymphs had reduced survival when their mothers matured on a same plant with R. padi. Both D. noxia and R. padi changed position on the plant more often when developing with S. graminum. Survival of second generation S. graminum nymphs was reduced when this species developed and reproduced in tandem with R. padi. Preferred feeding locations were S. graminum - primary leaf, D. noxia - tertiary leaf and R. padi - stem and these were not altered in any heterospecific combinations. Heterospecific aphids had no impact on fecundity or progeny survival in any species combination when fourth instars matured and reproduced on plants not previously exposed to aphid feeding, supporting the inference that systemic, aphid-induced changes in plant physiology mediated the effects observed when first instars developed and reproduced on the same plants

    The NA48 event-building PC farm

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    The NA48 experiment at the CERN SPS aims to measure the parameter (ϵ/ϵ)\Re(\epsilon'/ \epsilon) of direct CP violation in the neutral kaon system with an accuracy of 2×1042 \times 10^{-4}. Based on the requirements of: \\\\ * high event rates (up to 10 kHz) with negligible dead time;\\ * support for a variety of detectors with very wide variation in the number of readout channels;\\ * data rates of up to 150 MByte/s sustained over the beam burst;\\ * level-3 filtering and remote data logging in the CERN computer center; \\\\ the collaboration has designed and built a modular pipelined data flow system with 40 MHz sampling rate. The architecture combines custom-designed components with commercially available hardware for cost effectiveness and flexibility. To increase the available data bandwidth and to add filtering and monitoring capabilities, the original custom-built event builder hardware has been replaced by a farm of 24 Intel PentiumII based PCs running the Linux operating system during the shutdown between the 1997 and 1998 data taking periods. During the data taking period 1998 the system has been successfully operated taking ca. 70 Terabyte of data

    The Sustainable Development Goal on Water and Sanitation

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    Target 7c of the Millennium Development Goals (MDG 7c) aimed to halve the population that had no sustainable access to water and basic sanitation before 2015. According to the data collected by the Joint Monitoring Programme in charge of measuring progress towards MDG 7c, 2.6 billion people gained access to safe water and 2.3 billion people to basic sanitation. Despite these optimistic figures, many academics have criticised MDG 7c. We provide an overview of this critique by performing a systematic literature review of 61 studies conducted over the MDG implementation period (2002-2015) and shortly after. Our objective is to contribute to the debate on the operationalisation of the Sustainable Development Goal on water and sanitation (SDG 6). The academic debate on MDG 7c mainly focused on the effectiveness of the indicators for safe water and sanitation and on the political dynamics underlying the selection of these indicators. SDG 6 addresses some of the concerns raised on the indicators for safe water and sanitation but fails to acknowledge the politics of indicator setting. We are proposing additional indicators and reflect on the limitations of using only quantitative indicators to measure progress towards SDG 6
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