1,857 research outputs found
Determining potential for pollutant impacts in dynamic coastal waters: comparing morphological settings
No full textThe coastal focus and beach culture of Australia’s population in general, and the people of New South Wales in particular, mean that coastal systems are both highly prized and subjected to great pressures. The vast majority of the wastewater generated by the 7.3 million people of New South Wales is discharged directly to the ocean. The dispersion and fate of waterborne pollutants and their potential to impact coastal ecosystems are fundamentally determined by the dynamics of the coastal boundary layer (CBL). This turbulent interface between the coastline and the deep oceans is defined and classified for the first time in this thesis. Coastal morphologies and changes in the orientation of the coastline promote turbulence and strong gradients with extreme variability and heterogeneity over a broad range of scales. Conceptual models are presented to characterise New South Wales coastal boundary layer processes.
The broad aims of this thesis are to investigate the coastal boundary layer processes that affect dispersal and advection of pollutants, and to develop conceptual models and tools to facilitate coastal management.
Remote sensed ocean colour and sea surface temperature observations define meso-scale CBL phenomena, and this study demonstrates their application to support management decisions in relation to marine algal (phytoplankton) blooms. However, considerable scope exists to improve regional algorithms to deliver better ocean colour products for the optically complex (Case 2) waters of the inner coastal boundary layer.
Past failures to consider the CBL (morphological) settings of pollutant discharges to coastal waters have led to inefficient pollutant discharge systems and potential environmental impacts. Two case studies, investigate the principal forcing mechanisms and demonstrate the importance of morphology in controlling the dispersion and retention times of pollutants.
The first case study is focused on Sydney coastal waters where pollutant loadings are greater in magnitude and different in character than elsewhere in New South Wales. Here population pressures generate large wastewater loadings but the distances to offshore discharge locations are large compared to the scale of coastal roughness (headlands and bays) and the water is deep, thus reducing the risk of local retention of pollutants and increasing the potential for rapid dilution. By considering simulations of near field effluent plume behaviour in relation to long term ambient nutrient patterns specific periods of the year and depth intervals have been identified when outfalls would have an increased opportunity to influence bloom development, especially the upper half of the water column during late summer. However, algal blooms appear to be principally driven by seasonal oceanic nutrient enrichment. The research presented in this thesis, together with companion research previously published by the author and routine ongoing monitoring, indicate the viability of disposal of the Sydney’s excess sewage effluent (after source control and re-use options have been exhausted) via existing deepwater outfalls.
In contrast, inner CBL settings with coastal irregularities (e.g. headlands and bays) have a greater propensity to trap pollutants. A new hydrodynamically relevant morphological classification of New South Wales bays, headlands and islands provides both broad context for case studies and guides preliminary assessments for other locations. This classification reveals a borderline propensity for flow separation and re-circulation in the lee of Corambirra Point which is the focus of the second case study off Coffs Harbour in northern NSW. Direct observations and 3D finite difference hydrodynamic (Eulerian) and particle tracking (Lagrangian) model simulations quantify transient re-circulation associated with local current accelerations and a persistent shear zone located in the wake to the south of Corambirra Point. The flux of ambient water across the prescribed outfall alignment increases eighteen fold, over a shear zone spanning a cross-shore distance of just 1.4km (from 1.6km to 3km offshore). In contrast, the potential for re-entrainment and trapping of effluent in transient re-circulation cells was demonstrated to be insignificant. The proposed location of the outfalls was 1.5km offshore whereas the greatest gain per unit extension of the proposed discharge point coincides with the centre of the shear zone located ~2km offshore.
These case studies illustrate specific coastal boundary layer effects and indicate how an understanding of the spatial and temporal scales of these effects can be used to target more specific assessments of potential pollutant impacts. Simple morphological risk assessment tools are also presented to identify factors and processes which limit the exposure of sensitive environments to high pollutant concentrations and loads. Eddy retention effects are generally not incorporated in existing near field models but potential re-entrainment effects in wake zones can be assessed through the eddy retention value, which is introduced in this thesis. Although the approach presented here is focused on New South Wales coastal waters, the framework serves as a basis for general application elsewhere, and as a foundation for further refinement for application to NSW coastal waters.
Existing scientific literature indicates that coastal boundary layer processes also shape the distributions of the biological species and communities. This further motivates the development of a process based understanding of coastal boundary layer dynamics as a fundamental platform to support environmental protection and biodiversity conservation initiatives
Hydrothermal sediments are a source of water column Fe and Mn in the Bransfield Strait, Antarctica
No full textShort sediment cores were collected from ~1100 m water depth at the top of Hook Ridge, a submarine volcanic edifice in the Central Basin of the Bransfield Strait, Antarctica, to assess Fe and Mn supply to the water column. Low-temperature hydrothermal fluids advect through these sediments and, in places, subsurface H2S is present at high enough concentrations to support abundant Sclerolinum sp., an infaunal tubeworm that hosts symbiotic thiotrophic bacteria. The water column is fully oxic, and oxygen penetration depths at all sites are 2-5 cmbsf. Pore water Fe and Mn content is high within the subsurface ferruginous zone (max. 565 µmol Fe L-1, >3 to 7 cmbsf) — 14-18 times higher than values measured at a nearby, background site of equivalent water depth. Diffision and advection of pore waters supply significant Fe and Mn to the surface sediment. Sequential extraction of the sediment demonstrates that there is a significant enrichment in a suite of reactive, authigenic Fe minerals in the upper 0-5 cm of sediment at one site characterised by weathered crusts at the seafloor. At a site with only minor authigenic mineral surface enrichment we infer that leakage of pore water Fe and Mn from the sediment leads to enriched total dissolvable Fe and Mn in bottom waters. The largest Eh anomaly observed from our Bransfield Strait survey is associated with the elevated total dissolvable metal content in the water column above this coring site.. We hypothesize that the main mechanism for Fe and Mn efflux from the sediment is breach of the surface oxic layer by the abundant Sclerolinum sp., along with episodic enhancements by physical mixing and resuspension of sediment in this dynamic volcanic environment. We propose that Hook Ridge sediments are an important source of Fe and Mn to the deep waters of the Central Basin in the Bransfield Strait, where concentrations are sustained by the benthic flux, and Fe is stabilised in the water column as either colloidal phases or ligand-bound dissolved species. Entrainment of this water mass into the Drake Passage and thereby the Antarctic Circumpolar Current could provide a significant metal source to this HNLC region of the Southern Ocean if mixing and upwelling occurs before removal of this metal pool to underlying sediments. Sediment-covered volcanic ridges are common within rifted margins and may play a previously overlooked role in the global Fe cycle
Boxing Pandora Rethinking Borders, States, and Secession in a Democratic World
No full textA timely and provocative challenge to the foundations of our global order: why should national borders be unchangeable?The inviolability of national borders is an unquestioned pillar of the post–World War II international order. Fixed borders are believed to encourage stability, promote pluralism, and discourage nationalism and intolerance. But do they? What if fixed borders create more problems than they solve, and what if permitting borders to change would create more stability and produce more just societies? Legal scholar Timothy Waters examines this possibility, showing how we arrived at a system of rigidly bordered states and how the real danger to peace is not the desire of people to form new states but the capacity of existing states to resist that desire, even with violence. He proposes a practical, democratically legitimate alternative: a right of secession. With crises ongoing in the United Kingdom, Spain, Ukraine, Iraq, Syria, Sudan, and many other regions, this reassessment of the foundations of our international order is more relevant than ever.https://www.repository.law.indiana.edu/facbooks/1215/thumbnail.jp
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Boxing Pandora Rethinking Borders, States, and Secession in a Democratic World
No full textA timely and provocative challenge to the foundations of our global order: why should national borders be unchangeable?The inviolability of national borders is an unquestioned pillar of the post–World War II international order. Fixed borders are believed to encourage stability, promote pluralism, and discourage nationalism and intolerance. But do they? What if fixed borders create more problems than they solve, and what if permitting borders to change would create more stability and produce more just societies? Legal scholar Timothy Waters examines this possibility, showing how we arrived at a system of rigidly bordered states and how the real danger to peace is not the desire of people to form new states but the capacity of existing states to resist that desire, even with violence. He proposes a practical, democratically legitimate alternative: a right of secession. With crises ongoing in the United Kingdom, Spain, Ukraine, Iraq, Syria, Sudan, and many other regions, this reassessment of the foundations of our international order is more relevant than ever.https://www.repository.law.indiana.edu/facbooks/1215/thumbnail.jp
An observation of a transverse to longitudinal emittance exchange at the Fermilab A0 photoinjector:
No full textAn experimental program to perform a proof of principle of transverse to longitudinal emittance exchange has been developed at the Fermilab A0 Photoinjector. A new beamline, including two magnetic dogleg channels and a TM110 deflecting mode radio frequency cavity, were constructed for the emittance exchange experiment.
The first priority was a measurement of the Emittance Exchange beamline transport matrix. The method of difference orbits was used to measure the transport matrix. Through varying individual beam input vector elements, such as input x, x', y, y', z, or momentum and measuring the changes in all of the beam output vector's elements, output x, x', y, y', z, and momentum the full 6X6 transport matrix was measured. The measured emittance exchange transport matrix was in overall good agreement with our calculated transport matrix.
A direct observation of an emittance exchange was performed by measuring the electron beam's characteristics before and after the emittance exchange beamline. Operating with a 14.3 MeV, 250 pC electron bunch, longitudinal input emittance of 21.1+/-1.5 mm.mrad was observed to be exchanged with output horizontal emittance of 20.8+/-2.00 mm.mrad. Diagnostic limitations in the longitudinal output emittance measurement did not account for an energy-time correlation, thus potentially returning values larger than the actual longitudinal emittance. The horizontal input emittance of 4.67+/-0.22 mm.mrad was observed to be exchanged with the longitudinal output emittance of 7.06+/-0.43 mm.mrad. The apparent longitudinal output emittance growth is consistent with calculated values in which the correlation term is neglected.Ph.D.Includes bibliographical references (p. 160-164)by Timothy W. Koet
Porownanie zawartosci azotanow w splywach powierzchniowych w rejonie gorskim i wyzynnym
No full textPorównano zawartość azotanów w fazie ciekłej spływu powierzchniowego z 5 różnych użytków (ugór nienawożony, mieszanka koniczyny i tymotki, pszenżyto ozime, burak pastewny, ugór nawożony) położonych na stokach o nachyleniu 7 i 16% w rejonie górskim (Czyrna) i wyżynnym (Mydlniki) w latach 2003-2004.
Stężenie azotanów w spływach zależało od ilości, natężenia i terminu opadu w stosunku do zastosowanego nawożenia, nachylenie stoku, rodzaju użytku oraz pokrycia gleby roślinnością. Wielokrotnie większe stężenia N-NO₃ w obydwu miejscach badań wystąpiły w 2003 r. na skutek długich okresów suszy oraz intensywnych opadów, które wystąpiły bezpośrednio po zastosowaniu saletry amonowej. Mimo zbliżonej sumy opadów, znacznie większą koncentrację N- NO₃ miały spływy w rejonie górskim niż wyżynnym. W 2004 r. stężenia azotanów w spływach w obydwu rejonach były bardziej zbliżone, jednak nadal większe w rejonie górskim niż wyżynnym. Większe spływy ze stoku o nachyleniu 16% w Mydlnikach zwykle miały wyższe stężenie azotanów, zaś w Czyrnej średnio więcej azotanów zawierały spływy z użytków na stoku o spadku 7%. W obu rejonach najwięcej NO₃ zanotowano w spływach z ugoru nawożonego lub uprawy buraka pastewnego, a najmniejsze z ugoru nienawożonego, ale różnice koncentracji azotanów w spływach ze wszystkich użytków nawożonych w rejonie wyżynnym były mniejsze. Mieszanka koniczyny z tymotką oraz pszenżyto ozime w największym stopniu ograniczały stężenia azotanów w spływie ze względu na dobre pokrycie gleby roślinnością. Stężenia N- NO₃ w spływach przekraczało jego zawartość w wodach wrażliwych na eutrofizację, ale tylko po opadach w maju i czerwcu w 2003 r. można je zaliczyć do wód zanieczyszczonych według Dyrektywy Azotanowej.The content of nitrates in liquid phase of the surface runoff from 5 different kind of arable lands (unfertilized fallow, meadow clover and timothy mixture, winter triticale, fodder beet and fertilized fallow) situated on the slopes with 7 and 16% inclination in mountain (Czyrna) and upland (Mydlniki) regions in 2003-2004 were compared.
Nitrates concentration in runoffs depended on the amount, intensity and date of precipitation in relation to fertilizer application, slope gradient, kind of arable land and soil covering by vegetation. Many times higher NO₃-N concentrations in both locations were stated in 2003 as a result of long term drought periods and intensive rainfall immediately after ammonium nitrate application. Despite similar total amount of precipitation, considerably larger NO₃ concentrations contained the runoffs in mountain than in upland region. In 2004 nitrates concentrations in runoffs in both regions were more similar, though still higher in mountain than in upland region. Larger runoffs from slope with 16% gradient in Mydlniki had usually higher nitrates concentrations, however in Czyrna, on average, more nitrate contained runoffs from slope of 7% gradient. In both regions the highest NO₃ concentrations were noted in runoffs from fertilized fallow or fodder beet cultivation, and the smallest ones from unfertilized fallow. In upland region the differences of nitrate concentrations in runoff from all fertilized lands were visibly smaller. Clover with timothy mixture and winter triticale to largest extent reduced nitrate concentrations in runoffs because of good soil covering by vegetation. Runoff nitrate concentration surpassed their contents in waters sensitive to eutrophication, but according to „Nitrate Directive” one may pass to polluted waters only the runoffs after precipitation in May and June 2003
The Value of Knowledge: The Economics of Enterprise Knowledge and Intelligence Knowledge services/ Timothy Powell.
No full textIn English.Knowledge is an economic asset of great importance and value to the modern organization; however, it is too often not managed carefully as such. This book presents practical frameworks and methods for the knowledge professional -- and his/her organization -- to identify, actualize, and maximize the economic value of knowledge.Frontmatter -- Series Editor's Foreword: About Knowledge Services -- Preface -- Contents -- List of Figures -- List of Tables -- 1 Introduction to the Value of Knowledge -- 2 Knowledge as an Enterprise Function -- 3 Knowledge as an Economic Resource -- 4 The Knowledge Value Chain -- 5 Increasing Knowledge ROI -- 6 Knowledge to Value -- 7 Knowledge Strategy -- Appendix -- About the Author -- Other books by Timothy Powell -- Acknowledgments -- Intellectual Property Notices -- Works Cited -- Index1 online resource (xxi, 240 pages
W poszukiwaniu klucza do zrozumienia historii XX stulecia. Teoria historii i metodologia stosowana Timothy Snydera
No full textThe paper considers Timothy Snyder's applied methodology of history. Snyder's original field of interest as a professional historian was historical biography, but it did not take him long to put transnational history at the centre of his attention. The author posits that Snyder's practice in this historiographic paradigm has laid the foundation for his greatest academic achievements, leading to him being recognized as one of the best historians working today
Assuming Bosnia: Taking the Polity Seriously in Ethnically Divided Societies
No full textProfessor Waters\u27 contribution is titled Assuming Bosnia: Taking the Polity Seriously in Ethnically Divided Societies.https://www.repository.law.indiana.edu/facbooks/1062/thumbnail.jp
Ad Hoc Tribunals: Image, Origins, Pathways, Legacies
No full textProfessor Waters\u27 contribution to this volume is chapter 10 The Ad Hoc Tribunals: Image, Origins, Pathways, Legacieshttps://www.repository.law.indiana.edu/facbooks/1256/thumbnail.jp
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