Academic literature on the topic 'Combined sewage overflows'

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Journal articles on the topic "Combined sewage overflows"

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Carleton, M. G. "Comparison of Overflows from Separate and Combined Sewers – Quantity and Quality." Water Science and Technology 22, no. 10-11 (1990): 31–38. http://dx.doi.org/10.2166/wst.1990.0285.

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The use of separate sewerage systems to solve pollution problems associated with combined systems is examined. Overflows from combined stormwater-sewer systems have been found to be one of the major causes of receiving water pollution. Experiences in two countries which have predominantly one system or the other provided a basis for comparison. Wet weather overflow was found to be a major problem with similar quality of overflow produced for both systems. Minimising overflows was feasible, however proper and integrated control of stormwater and sewage flows, related to receiving water impacts, is indicated as the best solution. The use of separate sewerage systems to solve pollution problems may not be justified.
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Rechenburg, A., Ch Koch, Th Claßen, and Th Kistemann. "Impact of sewage treatment plants and combined sewer overflow basins on the microbiological quality of surface water." Water Science and Technology 54, no. 3 (2006): 95–99. http://dx.doi.org/10.2166/wst.2006.454.

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In a small river catchment, microbiological quality of different sewage treatment plants under regular conditions and in case of heavy rainfall, when combined sewage overflow basins (CSOs) are activated, was examined regarding microbial indicators and pathogens. In the watercourse, no self-cleaning effects could be observed. Small compact treatment plants discharge treated wastewater with a poor microbiological quality compared to river water quality and the quality of treated wastewater of larger plants. During storm water events, concentrations of microorganisms downstream of sewer overflows were approximately two logs higher than during dry weather conditions. Concentrations of parasites decreased slowly during the overflow, in parallel to filterable matter and particle-bound substances. The annual load of microorganisms originating from CSOs significantly exceeds the load from treated effluent of the sewage plants. Thus, an improved hygienic quality of the water course could be achieved by preventing overflows and by enhancing sewage treatment plants.
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Yomtovian, Isaac. "OPTIMUM ALTERNATIVES FOR CONTROLLING COMBINED SEWAGE OVERFLOWS - A CASE STUDY1." JAWRA Journal of the American Water Resources Association 15, no. 3 (2007): 628–43. http://dx.doi.org/10.1111/j.1752-1688.1979.tb00384.x.

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Guderian, Joachim, Andreas Durchschlag, and Jürgen Bever. "Evaluation of total emissions from treatment plants and combined sewer overflows." Water Science and Technology 37, no. 1 (1998): 333–40. http://dx.doi.org/10.2166/wst.1998.0079.

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Based upon the connection of a simulation program for combined sewer systems with the IAWQ-Activated Sludge Model No.1 the new simulation tool GEMINI was developed, which allows the calculation of sewer and sewage treatment plant as a unit. Some obtained results are presented in an example. They suggest, that for every treatment plant a rate of inflow is determinable, which leads to a minimum of total emissions out of sewer and treatment plant. The optimal value of sewage treatment plant inflow in the example is distinctly greater than the design flow rate fixed in German design rules. So it is recognizable that a rigid flow management for sewer and treatment plant does not always fulfil the aim of minimization of total emissions.
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Mielczarek, Szymon, and Jerzy M. Sawicki. "Dimensioning of vortex storm overflows." Water Science and Technology 78, no. 2 (2018): 259–65. http://dx.doi.org/10.2166/wst.2018.291.

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Abstract Vortex storm overflow is an interesting and useful technical solution, especially important in storm and combined sewage systems. However, there are no methods of this device dimensioning, which would be mathematically simple and properly precise physically. Such a method has been proposed in this paper, on the basis of investigations performed for the vortex separators and vortex flow controls. The essence of this method relies on the kinematic model of the velocity field and energy balance of the inflowing stream and dissipation. The procedure enables specialists to calculate the rise of the liquid free surface caused by the inlet stream energy and the hydraulic resistance of the bottom outlet. These mathematical relations are completed by two formulae: for the bottom ‘morning glory’ sink and for the upper overflow. The model has been positively verified during the laboratory measurements, so can be used during the technical dimensioning of the vortex storm overflows.
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Rutsch, M., I. Müller, and P. Krebs. "Dynamics of rain-induced pollutographs of solubles in sewers." Water Science and Technology 52, no. 5 (2005): 169–77. http://dx.doi.org/10.2166/wst.2005.0131.

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When looking at acute receiving water impacts due to combined sewer overflows the characteristics of the background diurnal sewage flux variation may influence the peak loads from combined sewer overflows (CSO) and wastewater treatment plant (WWTP) effluent significantly. In this paper, effects on the dynamic compounds transported in the sewer, on CSO discharges and WWTP loading are evaluated by means of hydrodynamic simulations. The simulations are based on different scenarios for diurnal dry-weather flow variations induced by different infiltration rates.
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Korving, H., M. Geise, and F. Clemens. "Failure of sewage pumps: statistical modelling and impact assessment." Water Science and Technology 54, no. 6-7 (2006): 119–26. http://dx.doi.org/10.2166/wst.2006.577.

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Sewage pumping stations are directly responsible for affecting performance, i.e. failing pumps may result in combined sewer overflows or flooding. However, failures of sewage pumps are not yet incorporated in sewer assessments due to lack of knowledge and data. This paper presents the analysis of pump failure data provided by two sewer management authorities in The Netherlands. Pump failures have been studied accounting for the nature of the failures, the operation and maintenance procedures of the management authority, the ageing of the pumps and the changes in the environment of pumps. The analysis shows that sewage pumps fail relatively often due to the composition of sewage and the discontinuous operation of the pumps. The interarrival time and the duration of failures are highly variable and independent of the pump type and the specific function of the pump. The results also indicate that the serviceability of sewer systems is significantly affected by failing pumps. As a consequence, part of the environmental damage due to CSOs (combined sewer overflows) can be avoided by improving maintenance of pumping stations.
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Hansen, O. B., C. Jacobsen, and P. Skat Nielsen. "Storm Water Loading of Greater Copenhagen Sewage Treatment Plant." Water Science and Technology 27, no. 12 (1993): 183–86. http://dx.doi.org/10.2166/wst.1993.0297.

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Copenhagen's plans to cut pollution loads from combined sewer overflows involves increased storage capacity in the sewer system, real time control of that system, and increased hydraulic loading for the treatment plant. Modelling studies have been used to examine the consequences.
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Schilling, W., and D. T. Kollatsch. "Reduction of Combined Sewer Overflow Pollution Loads by Detention of Sanitary Sewage." Water Science and Technology 22, no. 10-11 (1990): 205–12. http://dx.doi.org/10.2166/wst.1990.0306.

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For mixed combined/separate sewer systems it is proposed, in times of combined sewage overflows (CSO), to store sanitary sewage at the inlet point to the combined system. Thereby, sanitary sewage (with high strength) is kept in the system for further treatment after the storm whereas less-polluted CSO are diverted to the receiving water. By using data of an existing catchment different scenarios are evaluated and the potential benefit of sanitary sewage detention is quantified. This approach is compared to current German CSO regulations. It is more effective than conventional CSO detention if more than 60 % of the population upstream of the CSO diversion are served by a separate system. A key problem of this concept is the control strategy that determines when to activate and empty the storage tanks. A number of criteria are compared. Considerations are also made on operational aspects such as chemical transformations in stored sewage, maximum allowable detention time, and cleansing of storage tanks.
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Capodaglio, Andrea G. "INTEGRAL CONTROL REQUIREMENTS FOR SEWERAGE SYSTEMS." Water Science and Technology 30, no. 1 (1994): 131–38. http://dx.doi.org/10.2166/wst.1994.0014.

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Sewerage systems and sewage treatment plants are often planned, designed and operated as totally separate entities. As a result, sewage treatment efficiency is subject to considerable variability, depending both on general hydrologic conditions in the urban watershed (wet versus dry periods), and on specific “instantaneous” operating conditions. It has been postulated that the integration of design and operation in urban drainage and wastewater treatment could allow minimization of the harmful effects of discharges from treatment plants, combined sewer overflows and surface runoff. This “ideal condition” can be achieved through the introduction of so-called “Real-Time Control” technology in sewerage collection and treatment operations. This paper examines the requirements of a hypothetical integrated sewer flow and sewage treatment model, the mathematical tools used to design and operate Real-Time Control systems, and the issues emerging from an integration of the conveyance and disposal aspects of the sewerage cycle.
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Dissertations / Theses on the topic "Combined sewage overflows"

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Kappagantula, Srinivas. "Evaluation of Ballasted Sand Flocculation (BSF) and UV-Disinfection Technologies for Combined Sewer Overflows (CSOs)." See Full Text at OhioLINK ETD Center (Requires Adobe Acrobat Reader for viewing), 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=toledo1091232404.

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Thesis (M.S.V.)--University of Toledo.<br>Typescript. "A thesis [submitted] as partial fulfillment of the requirements of the Master of Science degree in Civil Engineering." Includes bibliographical references (leaves 107-110).
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Chiejina, Chidinma. "Identifying misconnection hotspots using coliforms and biofilm communities." Thesis, University of Hertfordshire, 2016. http://hdl.handle.net/2299/17352.

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Sewage misconnections currently pose severe threats to water quality especially in urban areas in the UK. These misconnections lead to the discharge of untreated wastewater into receiving watercourses via surface water outfalls. Regular discharges from this source could lead to these watercourses failing to meet standards set by the Water Framework Directives. Despite the impacts resulting from this urban diffuse pollutant source, research into this area is limited. The study area is the River Lee, which is known to experience issues with water quality especially within the heavily urbanized lower Lee section. Misconnections are one of the major contributors to the poor water quality status of the River. In this study, the Lee was investigated using several parameters. The approach involved the monitoring of coliform bacteria to detect outfalls where misconnections were likely, then biofilm samples below selected outfalls were used for both clean and polluted sites to look for community types. Results showed severe pollution within some sections of the River particularly within the lower Lee. Pymmes Brook was used as a case study, both coliform bacteria and biofilm communities below outfalls were further investigated for clean and polluted sites. Results from the Pymmes Brook study also showed that this watercourse was experiencing severe issues with water quality, with elevated levels of coliform bacteria identified below polluted outfalls. Biofilm community data obtained during the pilot and experimental phases of study were analyzed using a range of multivariate techniques. Results of the analysis showed consistent x patterns in community structure within sites with similar water quality, with indicator species identified. Communities below polluted outfalls were composed mainly of species tolerant of organic pollution thus indicating a response of communities to misconnection discharges. Currently, the identification of misconnections are carried out through trackbacks, a process which is expensive and time consuming. During this study an inexpensive and rapid approach is proposed for assessing misconnections within a catchment. Using this method, misconnection hotspots are mapped out using coliform bacteria and biofilm communities. Using catchment data and predicted coliform bacteria from enumerated counts, misconnections within these hotspots are assessed. Having tested this approach on Pymmes Brook, a tributary of the River Lee, the results obtained were promising. Pending further verification, this system provides an economical and rapid tool for the assessment of misconnections within a catchment.
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Näsman, Melander Emelie. "Dimensionering av åtgärder i kombinerade ledningssystem vid ökad spillvattenbelastning." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-179385.

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Ett allt vanligare uppdrag inom hydraulisk modellering är att undersöka hur nya bostads- och handelsområden påverkar statusen för äldre befintliga ledningsnät. I nya områden anläggs nästan uteslutande separatsystem och eftersom nya områden oftast uppförs utanför den befintliga bebyggelsen måste spillvattnet från dessa områden transporteras genom det befintliga avloppsnätet, vilket kan vara helt eller delvis kombinerat. I stadsdelen Hjorthagen i Stockholm planeras 5000 nya lägenheter att byggas och spillvattenflödet från dessa skall anslutas uppströms det befintliga kombinerade ledningsnätet i området. Examensarbetet har gått ut på att undersöka hur det kombinerade ledningssystemet påverkas av den tillkommande spillvattenbelastningen. Syftet var att undersöka hur den dimensionerande spillvattenavrinningen påverkar de åtgärder och kostnader som behövs för att få det utökade ledningsnätet att fungera, samt att utreda behovet av ytterligare anpassningar av ledningsnätet inför framtida klimatförändringar. Vid beräkning av bräddvolymer simuleras vanligen spillvattenavrinningen från medeldygnsförbrukning av vatten. I studien har det även ingått att undersöka om detta sätt ger lägre bräddvolymer jämfört med att variera vattenförbrukningen med ett veckomönster. Med modelleringsprogrammet MIKE Urban undersöktes tre fall av dimensionerande spillvattenflöde från det tillkommande området i Hjorthagen. Olika stor säkerhetsmarginal användes vid dimensioneringen. I alla tre fallen fick det tillkommande spillvattenflödet kapaciteten i det kombinerade ledningssystemet att överskridas redan vid torrväder, med bräddning som följd. Undersökningen visade att ju högre säkerhetsmarginal dimensioneringen innebar desto mer omfattande blev de åtgärder som krävdes för att få bräddningen att upphöra. Fallet med störst säkerhetsmarginal krävde ett utjämningsmagasin på 142 m3 och att dimensionen på 670 m ledning ökades från 400 mm till 600 mm med en uppskattad åtgärdskostnad på omkring nio miljoner kronor. De åtgärder som krävdes för att undvika bräddning vid torrväder var i alla tre fallen tillräckliga för att både minska bräddningen vid regnväder och för att klimatanpassa ledningsnätet. I de fall som undersöktes kunde ingen trend ses som visade att simulering av dag- och spillvattenavrinning, utan veckovariationer i vattenförbrukningen, skulle ge för låga bräddvolymer.<br>An increasingly common assignment in hydraulic modeling is to investigate how sewage from new residential and commercial areas affect the status of existing sewer systems. In new areas the sewer systems are constructed to operate separately from storm drains and since new areas often are founded in the outskirt of existing areas the sanitary sewage from these areas must be transported through the older existing sewer system, which can be completely or partly combined. In the district of Hjorthagen in Stockholm 5,000 new apartments are planned to be built and sewage from these must be connected upstream of existing combined sewer system in the area. The purpose of this master thesis was to investigate how combined sewer system is affected by additional sewage load. The aim was to investigate how the choice of design sewage flow affects the measures and costs necessary to get the extended sewer system to function, and to consider the need for further adjustments to future climate change. When calculating volumes of combined sewer overflow the sewage flow usually is simulated as discharge from average water use. One objective with this thesis was to investigate whether this method gave lower volumes of combined sewer overflow as compared to using a weekly pattern. By using the modeling program MIKE Urban three choices of design sewage flow, from the new area in Hjorthagen, were investigated. The margin of safety when designing the sewage flow was increased in each case. The results showed that the capacity of the combined sewer system was exceeded during dry weather, with overflow as a result. The investigation showed that the higher margin of safety used the more extensive measures was needed. The greatest margin of safety required a storage basin of 142 m3 and that the dimension of 670 m of pipes was increased. To stop the overflow at dry weather the measures required in each case were sufficient to both reduce overflow during wet weather and to adjust the sewer system to future climate. Simulating the rainfall runoff and sewage flow, without weekly variations in water consumption did not underestimate the volumes of combined sewer overflow compared to varying the water use.
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Stern, Zachary Elfonte. "Reducing combined sewage overflows : the essentials of a sustainable stormwater management plan." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-05-3018.

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This report examined efforts to manage combined sewage overflows and create effective stormwater management plans. To provide background on the issue, a brief history of sewage management was provided, along with the legal history regarding water quality, sewage and CSOs, effects of CSOs and current green infrastructure methods for dealing with CSOs. The report then compared the efforts of three cities--Portland, Oregon; Philadelphia, PA; and Chicago, IL--to improve water quality and manage CSOs and stormwater. From the examination of the efforts of these cities the author derived a list of ten recommended elements for a CSO/stormwater management plan. These recommended elements were then used to evaluate New York City's recently released sustainable stormwater management plan and its prospects for success.<br>text
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Books on the topic "Combined sewage overflows"

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Richard, Field. Management of combined sewer overflows. Lewis Publishers, 2004.

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Management of combined sewer overflows. Lewis Publishers, 2003.

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True, John Nathan. Maine combined sewer overflow: 2009 status report. Division of Water Quality Management, Bureau of Land and Water Quality Control, Department of Environmental Protection, 2010.

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True, John Nathan. Maine combined sewer overflow: 2006 status report. Division of Water Quality Management, Bureau of Land and Water Quality Control, Dept. of Environmental Protection, 2007.

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True, John Nathan. Maine combined sewer overflow: 2006 status report. Division of Water Quality Management, Bureau of Land and Water Quality Control, Dept. of Environmental Protection, 2007.

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True, John Nathan. Maine combined sewer overflow: 2006 status report. Division of Water Quality Management, Bureau of Land and Water Quality Control, Dept. of Environmental Protection, 2007.

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Breau, David P. Maine combined sewer overflow: 2011 status report. Division of Water Quality Management, Bureau of Land and Water Quality Control, Dept. of Environmental Protection, 2011.

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Boer, B. de. Effecten van directe vuilemissies uit het gemengde rioolstelsel van Loenen op de waterkwaliteit van de ontvangende bergingsvijer. Ministerie van Volkshuisvesting, Ruimtelijke Ordening en Milieubeheer, 1986.

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Virginia. General Assembly. Joint Subcommittee Studying Combined Sewer Overflows in the Commonwealth. Interim report of the Joint Subcommittee Studying Combined Sewer Overflows in the Commonwealth to the Governor and the General Assembly of Virginia. Commonwealth of Virginia, 1990.

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Wilkison, Donald H. Effects of wastewater and combined sewer overflows on water quality in the Blue River basin, Kansas City, Missouri and Kansas, July 1998-October 2000. U.S. Dept. of the Interior, U.S. Geological Survey, 2002.

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Book chapters on the topic "Combined sewage overflows"

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Loucks, Eric, David Watkins, and Theresa Culver. "Combined Sewer Overflows in the Milwaukee Metropolitan Sewerage District Conveyance and Treatment System." In Water Resources Systems Analysis through Case Studies. American Society of Civil Engineers, 2013. http://dx.doi.org/10.1061/9780784412879.ch02.

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Conference papers on the topic "Combined sewage overflows"

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Mamouri, Sina Jahangiri, Saad A. Ghalib, and André Bénard. "Numerical Investigation of the Efficiency of the Treatment Shaft for Separation of Suspended Solids in Wastewater Treatment." In ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/fedsm2018-83347.

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A combined sewer system is a facility that collects both municipal sewage and surface runoffs. These facilities may overflow (combined sewer overflow or CSO) during large storms which results in serious pollution, i.e. the flows exceed the capacity of the treatment plant. An approach to reduce the number of combined sewer overflows is to store rainfall runoffs temporarily [1]. The Treatment Shaft system is a relatively new but proven patented technology (U.S. Patent [2] and other patents) that includes the necessary CSO control and treatment, with less footprints than existing systems, and at a reduced cost. In this system, wastewater is collected in a large shaft equipped with baffles and partitions designed to ensure a very slow velocity within the system. In this study, the efficiency of the Treatment Shaft system for separation of solid contents without the use of flocculation agents is investigated. Moreover, the effect of geometry modifications on the separation efficiency is evaluated. For this purpose, a Computational Fluid Dynamics (CFD) approach for multiphase flow of particulate wastewater is used to evaluate the performance of various Treatment Shaft designs for a 10-year, 1-hour rainstorm event. It is shown that the Treatment Shaft is an effective technology to separate particles larger than 175μm, and more than 50% of the particles of size 175μm or more are settled. Additionally, several design variations are assessed and a design with a less footprint is specified.
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Vasconcelos, Jose G., and Steven J. Wright. "Surge Associated With Air Expulsion in Near-Horizontal Pipelines." In ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45265.

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A number of situations of engineering interest are associated with the relatively rapid filling of a nearly horizontal pipeline. The displacement of the air may lead to a number of different transient conditions of concern in engineering design. Our specific application relates to the use of underground storage tunnels to mitigate combined sewage overflows. Historically, the operation of these system have created surges initiated when the tunnel passes to a surcharged condition that have resulted in “geysering” in which an air/water combination is expelled to the ground surface through manholes or other risers. Numerical models that have been created to describe the phenomena generally treat the air as a passive phase that exists at atmospheric pressure and disappears when the water fills the tunnel. In an attempt to understand the conditions leading to extreme surges, a physical model that reproduced the essential elements of the tunnel filling process was created. This model was filled at one end in a fill box in which the maximum water level was controlled with an overflow weir. A surge riser was mounted at the opposite end of the pipeline to observe the magnitudes of surges created under a number of different flows created by varying the inflow rate, the initial water level in the pipe, and the pipe slope. In general, initiation of the filling process generated a hydraulic bore that propagated through the system until the tunnel reached a surcharged state and the maximum surge generated depends on the dynamics of the bore. However, under certain flow conditions, the water level in the surge riser was observed to increase prior to the arrival of the bore, an occurrence that can only be explained by pressurization of the air in the pipe. Subsequent experiments confirmed this explanation and a modified experimental setup was created to elucidate the important effects of the air. Measurements were made of a number of key flow variables and are found to be consistent with the predictions of a numerical model that considers the elementary dynamics of the air.
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Liqun, Cao, Wang Jianzhong, Lu Renquan, Theodore E. Simos, George Psihoyios, and Ch Tsitouras. "Minimization Method for Combined Sewage Overflow of Urban Drainage." In NUMERICAL ANALYSIS AND APPLIED MATHEMATICS: International Conference on Numerical Analysis and Applied Mathematics 2009: Volume 1 and Volume 2. AIP, 2009. http://dx.doi.org/10.1063/1.3241470.

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