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Water quality modeling for the Kennet and Avon Canal, a navigational canal in an inland catchment
No full textThe Kennet and Avon Canal in southern England is experiencing severe water quality problems caused by inorganic sediment and algae. These water quality problems are affecting the angling sport of fishermen downstream of the confluence of the canal with the River Kennet. The Environment Agency has been called upon to remedy these issues, but before proceeding they desire a computer model capable of predicting the water quality impacts of various scenarios under consideration. No such model was available to them.
This project identified the key solids generation and transport processes to be included in a water quality model for inland navigational canals. Where available, equations from the literature describing relevant processes were used or modified for inclusion in a canal modeling algorithm. Where literature was not available, water quality samples were taken to characterize needed relationships. The final algorithm was coded and tested using a simplified dataset that allowed clear evaluation of the simulated processes.
After successful testing, the canal model was applied to the Kennet and Avon Canal. The time series predicted by the model were compared to observed hydrological, solids, and chlorophyll-a (representing algae) data at multiple points in the canal. The model adequately predicted all of these constituents at the monitored locations.
The final task in the project required evaluation of six management scenarios proposed by the Environment Agency to address the water quality problem. The model suggests that filtration or other treatment of water in the canal near the confluence with the river is the best management option, as it will address both the elevated inorganic sediment and algae concentrations at the most critical point in the canal. Less desirable options include efforts that only target inorganic sediment, which could increase algal concentrations by increasing light availability; and diversion of surface flows from the canal, which could possibly damage the hydrologic balance of the canal while encouraging undesirable algal growth
A ampliação do Canal do Panamá: motivações comerciais e reformas institucionais
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Sócio-econômico, Programa de Pós-graduação em Relações Internacionais, Florianópolis, 2013Abstract: The Panama Canal is located in Central America in the Republic of Panama. Its strategic location allows connecting the Atlantic and Pacific Oceans through an isthmus of 83 km long and 26 meters high. Due to the extremely natural complexity, its construction has become a major engineering challenge, the first French attempt failed between 1881-1889 and was completed by the U.S. military in the period 1904-1914. Meanwhile, Panama became an independent country - with direct U.S. aid - and subsequently signed an international treaty with the United States for the construction, administration and sovereignty of the Canal Zone by the Americans. Given the expansion of international trade after World War II the traffic capacity of the Canal has become a limiting factor for the passage of larger vessels. Furthermore, the internal problems associated growing disinterest on the American Canal led to a renegotiation of the treaty with the USA. Thus, in 1977 both countries signed the Torrijos-Carter Treaty whose goal was a gradual transition from 20 years to the full Panamanian control and management over the sovereignty of the Canal. Within this period of transition (1979-1999), the U.S. overthrew dictator Noriega in 1989 under the fear of the weakening of the bilateral relations between the countries as well as ensuring free flow of trade at the Canal. Thus, the process of democratization started in the 1990s provided the input Foreign Direct Investment, privatization and modernization for the Panamanian Port Sector. With the end of the transition period and the Canal Zone in 1999, the newly created agency ACP acquired administrative autonomy and now manages the Canal as a public entity with a focus on providing quality services which consequently became in a financial surplus entity. Therefore, the Canal?s duplication project was approved in a national referendum in 2006 and the construction work began in 2008. With the duplication it is expected to strengthen the flow of trade between the Americas and Asia, mainly from USA, China, Japan, Korea and Chile. Similarly, there is an opening up prospects for advancement Brazilian trade due to transport infrastructure projects by the Brazilian federal government to strengthen the use of ports in the North and Northeast of Brazil
Evaluation on the anatomic variations of the mandibular canal using cone beam computed tomography and panoramic radiography
No full textTCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências da Saúde. Odontologia.Some procedures in dentistry, as anesthesia, dental implants placement and third molars extraction may vary the degree of difficulty and surgical complications, due to specific and individual anatomy of each patient. Detecting these variations is considerably relevant to the dentist, who is able to avoid and/or prevent intraoperative or postoperative complications. Focusing on the challenges in the mandible, this study aimed to assess the prevalence of anatomical variations of the mandibular canal, determining the most frequent, and comparing the results with those found in previous studies. 60 human cadavers’ jaws were submitted to radiographic and tomographic examinations, which were analyzed by a single calibrated observer. In the panoramic radiographs analysis the forward canal was the most common, registering 8,3%, while in the analysis of CT scans, the retromolar canal proved that it is more frequent, 35%. Cone-beam computed tomography proved to be more effective in the diagnosis of anatomical variations of mandibular canal and must be requested whenever exists suspicions of bifid mandibular canal in panoramic radiography.Alguns procedimentos na odontologia, como anestesias, instalação de implantes dentários e extrações de terceiros molares podem variar quanto ao grau de dificuldade e complicações cirúrgicas, devido à anatomia específica e individual de cada paciente. Detectar essas variações é de considerável relevância para o cirurgião dentista, sendo esse, capaz de evitar e/ou prevenir complicações transoperatórias ou pós-operatórias. Com enfoque nas alterações presentes na mandíbula, este estudo teve como objetivos avaliar a prevalência das variações anatômicas do canal mandibular, assim como comparar os resultados obtidos na análise de tomografias computadorizadas de feixe cônico, com os encontrados na análise de radiografias panorâmicas. Para tal, 60 mandíbulas de cadáveres humanos foram submetidas a exames radiográfico e tomográfico, os quais foram analisados por um único observador calibrado. Na análise das radiografias panorâmicas o canal duplicado em braço foi o mais comum, 8,3%, enquanto na análise das tomografias, o canal retromolar mostrou-se muito mais frequente, 35%. A tomografia computadorizada de feixe cônico mostrou-se muito mais eficaz no diagnóstico de variações anatômicas do canal mandibular e deve ser solicitada sempre que houver suspeita de duplicação do canal na radiografia panorâmica
Model of Lock 37 and Alexander-Wilson Mill 3
No full textOne black and white photographic print of a model of Lock 37, also known as the Alexander Lock or 14 mile lock, and the Alexander Mill, later known as the Wilson Feed Mill and sometimes referred to as the Alexander-Wilson Mill, on the Ohio and Erie Canal near Sagamore Hills in Summit County and Valley View in Cuyahoga County, Ohio. The model was constructed by Louis G. Gruhling of Akron in 1981, commissioned by they Cuyahoga Valley National Recreation area or CVNRA. It was displayed at the Canal Visitor Center on Canal Road in Valley View
Model of Lock 37 and Alexander-Wilson Mill 2
No full textOne black and white photographic print of a model of Lock 37, also known as the Alexander Lock or 14 mile lock, and the Alexander Mill, later known as the Wilson Feed Mill and sometimes referred to as the Alexander-Wilson Mill, on the Ohio and Erie Canal near Sagamore Hills in Summit County and Valley View in Cuyahoga County, Ohio. The model was constructed by Louis G. Gruhling of Akron in 1981, commissioned by they Cuyahoga Valley National Recreation area or CVNRA. It was displayed at the Canal Visitor Center on Canal Road in Valley View
Model of Lock 37 and Alexander-Wilson Mill
No full textOne black and white photographic print of a model of Lock 37, also known as the Alexander Lock or 14 mile lock, and the Alexander Mill, later known as the Wilson Feed Mill, on the Ohio and Erie Canal near Sagamore Hills in Summit County and Valley View in Cuyahoga County, Ohio. Water can be seen flowing in the foreground while trees stand in the background. The model was constructed by Louis G. Gruhling of Akron in 1981, commissioned by they Cuyahoga Valley National Recreation area or CVNRA. It was displayed at the Canal Visitor Center on Canal Road in Valley View
[Northwestern Victoria] [cartographic material] /
No full textMap of northwestern Victoria showing land requested by the Grand Victorian North-western Canal Company (overprinted in green) for planned navigation, drainage channel routes, proposed irrigation stations, counties, towns and railways. Relief shown by hachures.; Title supplied by cataloguer.; In upper right corner: Progress - peace - & - plenty. GVNWCC.; In lower left margin: H.G. de Gruchy & Co.; In lower right margin: Lith. Melbourne.; Includes index to map.; Also available in an electronic version via the Internet at: http://nla.gov.au/nla.map-rm1022; Library copy has faulty printing with offsetting from green plate occurring over parts of the map.North west Victori
Picture of Heidloff Boys
No full textOne black and white photocopy of a portrait of four boys sitting together on the Ohio and Erie Canal at Lock 42 and the Gate Keeper's House west of Independence Road in Cleveland in Cuyahoga County, Ohio. Pictured are: Unknown, William H. Heidloff, Raymond C. Heidloff, and Roy G. Heidloff
Second Welland Canal - Book 3, Survey Map 1 - Canal to Chippewa Creek with Port Robinson
No full textSurvey map of the Second Welland Canal created by the Welland Canal Company showing Port Robinson and the canal to Chippewa Creek.
The surveyors' measurements and notes can be seen in red and black ink and pencil.
Local area landmarks are also identified and include streets and roads (ex. Front Street, Bridge Street, and Cross Street), the Welland railroad, Dry Dock leased to D. McFarland and Abbey, G. Jordan Tavern, D. McFarland and Co. Burnt Saw Mill, I. Pew Shop, Old Locks, New Lock, Canal to Chippewa Creek, Chippewa Creek, covered drain from dry dock, a barn and several bridges.
Properties and property owners of note are: Lots 202, Broken Front lots 202 and 203, D. McFarland, and G. Jordan
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