Canal Alignment Research Articles

Feasibility of a Novel Surface-Guided Setup Technique to Reproduce Neck Curvature Using two Regions of Interest.

To improve the setup reproducibility of neck curvature using real-time optical surface imaging (OSI) guidance on 2 regions of interest (ROIs) to infer cervical spine (c-spine) curvature for surface-guided radiotherapy (SGRT) of head-and-neck (HN) and c-spine cancer. A novel SGRT setup approach was designed to reproduce neck curvature with 2 ROIs: upper-chest ROI and open-face ROI. It was hypothesized that the neck curvature could be reproduced if both ROIs were aligned within ±3 mm/2˚ tolerance. This was tested prospectively in 7 volunteers using real-time 3D-OSI guidance and lateral 2D-photography verification after the 3D and 2D references were captured from the initial conventional setup. Real-time SGRT was performed to align chest-ROI and face-ROI, and the longitudinal distance between them was adjustable using a head-support slider. Verification of neck curvature anteriorly and posteriorly was achieved by overlaying edge-extracted lateral pictures. Retrospectively, the relationship between anterior surface and spinal canal alignment was checked in 11 patients using their simulation CT (simCT) and setup cone-beam CT (CBCT). After the anterior surface was rigidly aligned, the spinal canal alignment was checked and quantified using the mean-distance-to-agreement (MDA) and DICE similarity index, and surface-to-spine correlation was calculated. The reproducibility of neck curvatures using the 2xROI SGRT setup is verified and the mean neck-outline-matching difference is within ±2 mm in lateral photographic overlays. The chest-ROI alignment takes 110 ± 58 s and the face-ROI takes 60 ± 35 s. When the anterior body surface is aligned (MDA = 1.1 ± 0.6 mm, DICE = 0.96 ± 0.02,) the internal spinal canal is also aligned (MDA = 1.0 ± 0.3 mm, DICE = 0.84 ± 0.04) in 11 patients. The surface-to-spine correlation is c = 0.90 (MDA) and c = 0.85 (DICE). This study demonstrates the feasibility of the novel 2-ROI SGRT setup technique to achieve reproducible neck and c-spine curvature regardless of neck visibility and availability as ROI. Staff training is needed to adopt this unconventional SGRT technique to improve patient setup.

Evaluation Of Drainage Canal Mitigation In Banjarmasin City Post Hydrometeorological Disaster

Data from the Environmental Health Risk Assessment (EHRA) study in 2012 stated that 52% of inundation in Banjarmasin City was caused by a problematic drainage system, the causes of which included siltation of the canals and the large number of weeds growing around the drainage canals, which would interfere with the function of the drainage canals. The data used are road canal cross-sectional dimensions, topographical data, canal alignment data, and land use data in North Banjarmasin Sub District. The calculation analysis method uses the Mononobe method. The results of these calculations will later be used for modeling which are indicated to exceed the water capacity, of course also by adding topographical parameters, land use, and canal alignment. Meanwhile, the planned discharge data from the results of the calculated rainfall and the measuring data of the channel cross-sectional dimensions are used for detailed modeling of the channel cross-section using HecRas. The condition of drainage channels is over-capacity, influenced by the presence of several channels covered with bushes and concrete, the amount of sediment that has not been dredged, the absence of an adequate catchment area system due to the characteristics of the soil in the form of peat soil.

Cervical Spinal Cord Surgical Stabilization in a Sheep

Background: Trauma is the main cause of spinal fractures and dislocations in humans and large animals. Clinical signs present with acute onset and vary according to the location and severity of the spinal cord injury. The treatment of fractures in large animals depends on economic value, cost of procedures, prognosis, location and type of fracture. However, although spinal fractures in large animals are not uncommon, the literature about their clinical aspects and treatment is scanty. Therefore, the purpose of this report is to describe a surgical stabilization of atlantoaxial subluxation, fracture of the third cervical vertebra and C2-C3 subluxation.Case: An approximately 2-year-old Île-de-France sheep, weighing 101 kg, with a history of cervical trauma and non-ambulatory tetraparesis was treated at the Veterinary Hospital of the Institution (UNIPAMPA). During physical examination, the animal presented good general physical condition and heart rate, respiratory rate and temperature was according to physiological parameters for the species. The animal remained in lateral decubitus, with minimal head and limb movements, and exhibited deep pain sensitivity. Clinical treatment with dexamethasone, limb physiotherapy and change in lateral decubitus position were employed, but failed to improve the animal’s condition. After five days of unresponsive to clinical treatment, the patient was referred to the neurology department, where it underwent neurological examination and radiographic examination of the cervical region was performed under general anesthesia. The radiographic examination revealed atlantoaxial subluxation, by displacement of the odontoid process into the vertebral canal, fracture of the third cervical vertebra and C2-C3 vertebral subluxation. The surgical planning aimed cervical vertebral instability repair using atlantoaxial arthrodesis associated the stabilization of C1-C2 and C2-C3 vertebrae with Schanz pins and bone cement, due facility and versatility this association. The postoperative radiographic examination showed incomplete insertion of the Schanz pin into the left Atlas wing and a cervical collar was recommended. The clinical evaluation was performed daily, and after 23 days of surgery the animal could crawl in lateral decubitus besides assisted walking ability. However, the animal died 36 days after surgery due to severe dyspnea. A necropsy revealed pulmonary edema and hepatic lipidosis, besides hepatic septic thrombus. Moreover, the vertebral canal of C1-C2 and C2-C3 segments stayed realigned and stabilized, without spinal cord injury and trachea compression.Discussion: Non-ambulatory tetraparesis, and minimal head and limb movements confirm severe spinal cord injury. The failure of clinical treatment, craniocervical instability in C1-C2 and C2-C3 and the high economic and genetic value of patients was definite for the surgical indication, besides reserved prognosis. The surgical treatment aim is recovery motor function from spinal cord decompression, vertebral canal realignment and the stabilization of vertebral instability. The cervical collar was placed on the patient after the surgery was intended to prevent rotation of the atlantoaxial joint, aiding vertebral stability. It is believed that the recovery of large animals with spinal cord injuries like in this case report is slower due to their heavy weight and the difficulty in managing such patients. This case report confirms that the techniques employed here achieved the proposed objectives of spinal canal alignment and spinal stabilization, showing improvement of clinical signs and recovery of the animal’s limb and neck movements.

Dense DSM and DTM Point Cloud Generation Using CARTOSAT-2E Satellite Images for High-Resolution Applications

The primary objective of this study is to provide a methodology to generate a dense point cloud of digital surface model (DSM) and digital terrain model (DTM) from 0.6 m GSD stereo images acquired by CARTOSAT-2E satellite of the Indian Space Research Organization. These products are required for many high-resolution applications such as mapping of watersheds and watercourses; river flood modeling; analysis of flood depth, landslide, forest structure, and individual trees; design of highway and canal alignment. The proposed method consists of several processes such as orienting the stereo images, DEM point cloud extraction using the semi-global matching, and DSM to DTM filtering. The stereo model is built by performing aero triangulation and block adjustment using the ground control points. The semi-global matching algorithm is used on the epipolar images to generate the DSM in the form of dense point cloud corresponding to one height point for each pixel. The planimetric and height accuracies are evaluated using orthoimages and DSM and found to be within 3-pixel (~ 2 m) range. A method for extracting DTM by ground point filtering, to discriminate the probable ground points and the non-ground points, is provided by using discrete cosine transformation interpolation. This robust method uses a weight function to differentiate the noise points from the ground points. The overall classification efficiency kappa (κ) value averages at 0.92 for ground point classification/DTM extraction. The results of benchmarking of the GPS-aided GEO augmented navigation GPS receiver by operating it over IGS station, in static mode for collecting the checkpoints, also are presented.

Geotechnical Investigations for the Ponnaiyar-Palar Intra State Link Canal Project (Borrow Area and along the Canal Alignment)

Geotechnical Investigations for the Ponnaiyar-Palar Intra State Link Canal Project (Borrow Area and along the Canal Alignment)

GIS based Irrigation Canal Alignment in Wayanad District, Kerala

GIS based Irrigation Canal Alignment in Wayanad District, Kerala

Screw Loosening and Pelvic Canal Narrowing After Lateral Plating of Feline Ilial Fractures With Locking and Nonlocking Plates.

To compare the frequency of complications, including screw loosening and pelvic canal narrowing, associated with dynamic compression plating, locking plating, and double locking plating of ilial fractures in cats. Historical cohort study. The radiographs and medical records of cats with pelvic fractures that were presented between 2004 and 2013 were reviewed. The cases were categorized based on the plate type and number as dynamic compression plate (DCP), single locking plate (LPS) and double locking plates (dLPS). The frequency of screw loosening was compared across categories using a Fisher's exact test. The change in pelvic alignment, described by the change in sacral index (postoperative sacral index-followup sacral index), was compared across plate categories using ANOVA. The frequency of screw loosening for DCP (5/10) was significantly higher than LPS (1/13) and dLPS (0/11) (P = .05, P = .012, respectively). There was no significant difference in the SI change across plate categories. The mean change in sacral index for DCP was -0.11 (95%CI -0.25 to 0.03), for LPS was 0.0007 (95%CI -0.07 to 0.08), and for dLPS was -0.01 (95%CI -0.04 to 0.02). None of the cats showed constipation postoperatively. Screw loosening occurred less often but the change in pelvic canal alignment was not significantly different in ilial fractures repaired with LPS or dLPS compared to ilial fractures repaired with DCP. Locking plating of ilial fractures in cats may offer advantages compared to nonlocking plating.

Tibial Stems in Revision Total Knee Arthroplasty: Is There an Anatomic Conflict?

Tibial stems are frequently used in revision total knee arthroplasty (TKA). We investigated the effect of tibial stems on final component alignment and tray position. Thirty 3D reconstructed cadaveric tibial models were classified according to canal bow angle. After virtual implantation of 120 mm and 200 mm stemmed tibial components, deviation from native mechanical axis was measured. Tibial alignment valgus malposition of up to three degrees occurred and most pronounced with 120 mm stems. Canal alignment using 200 mm stems deviated tray position medially and posteriorly. Mild to moderate valgus bowing of the tibial canal is not uncommon (57% in our series) possibly leading to valgus malalignment. Anatomic conflict between the tibial mechanical axis and intramedullary canal can exist, with alignment and tray placement implications.

SELECTION OF ALIGNMENT FOR FEEDER CANAL FROM PILLAIPALLY FLOOD FLOW CANAL TO WANKAMAMIDI TANK IN NALGONDA DISTRICT

Selection of alignment for a canal is critical in terms of cost and execution time. Several alignments may be possible between the source and destination of a canal, but command area and cost of work is more important. Canal works costs include the cost of earthwork both for embankment and cuttings. This paper presents the study of Flood Flow Canal from Pillaipally Anicut to the Minor Irrigation Tanks of Bhudan Pochampally, Chotuppal, Ramannapet and Chityal Mandals in Nalgonda District. With the use of Toposheets and Satellite Image (CartoDEM), various thematic layers such as watershed, streams, contours are prepared. ArcGIS 10.2 desktop software and Google Maps API is used for data preparation, analysis and planning for canal alignment of feeder canal to Wankamamidi Tank.

Geospatial Techniques for Efficient Conservation and Management of Surface Water for Irrigation in Joganbedi Village, Khargone District, Madhya Pradesh, India

Abstract. The study aimed at developing improved methods based on remote sensing and GIS techniques to increase cultivated area under irrigation. Landuse / landcover mapping was considered as the key component to prioritize locations for constructing appropriate recharge structures. Joganbedi scheme was proposed for this study. Joganbedi is situated 13 km. from Khargone, district Khargone, Madhya Pradesh, India. Command area of the proposed scheme lies in Beda sub-basin which is a tributary of the Narmada River. This area is of hard rock terrain and is occupied by the Deccan basalt. The main objective of the study was surface water conservation and management via multi-spectral information resulting from remotely sensed data to increase irrigation. High resolution GeoEye1 stereo images were used for generation of DEM, contour, landuse/landcover mapping, lineaments and drainage mapping. DEM was used for canal alignment. and further, contours were used to determine catchment, submergence /FRL, and command areas. Landuse/landcover statistics of submergence area helped to identify different land classes within the study area. These parameters are required for scheme planning. Additionally, rainfall data, maximum drawdown level, and dam height were collected as supporting parameters. The study concludes that landuse/landcover mapping is useful in identification of surface water conservation and management plan for irrigation purpose. It also proves that implementation of Joganbedi scheme will increase the cultivated area under irrigation, facilitate the farmers for multi season cropping and help in improving their economic condition.

Sethusamudram Shipping Canal Project: In Need of Divine Intervention

The case looks at the Sethusamudram Shipping Canal Project from its inception in the year 1860 to 2012 when the Pachauri Committee was about to submit a report on the latest canal alignment (4A) as suggested by the Supreme Court. It takes the reader through a series of developments starting from the initial proposals and alignments to formation of Sethusamudram Corporation Limited and highlights the impact of National Environmental Engineering Research Institute Report, Tsunami Detailed Project Report, and Subramaniam Swamy Report on various issues including environmental, political, religious, security and legal. The case brings out multi-dimensional aspects involved in an Indian infrastructure project and gives both students and the faculty an opportunity to explore the complexities faced by the Indian decision makers in today's context.

Optimal alignment of a canal route

The paper describes a method of optimising the alignment of an irrigation canal. Several alignments may be possible between the source and destination of a canal, but cost minimisation is important. Canal alignment costs include the cost of earthworks in embankments and excavations. Formulation of the cost function for earthworks is difficult in undulating terrain. In the present study, the topography of a given area is expressed as a double Fourier series to overcome this problem. The cost function is then formulated for the canal route, taking account of the longitudinal profile of the canal as it crosses the terrain. To arrive at a minimum cost route of a canal, several alignments can be evaluated by subdividing each alignment into segments.

Surface Water Management in Machhu Dam Command Area using Geo-Informatics Techniques

is the most important natural resource; it is the most basic human need and a valuable national asset. Water is one of nature's most important gifts to mankind. Efficient development and optimized utilization of water resources therefore, is of great significance to the overall development of the country. In Rajkot district (India) the Machhu Dam was built for supplying drinking water to urban areas. The present study on Surface Water Management in Machhu Dam Command Area (Rajkot District) using Geo-Informatics Techniques was carried out in the Aji and Machhu dam Catchment areas, using Indian Remote Sensing Satellite digital data and Geoinformatics technology. The surplus water availability in major reservoirs and dams was computed from the data collected from Flood Control Cell (FCC) government of Gujarat. It was observed from the FCC data analysis, the Machhu river have surplus water during 2007-2011.Therefore, this study on diverting of surplus water through canals, ponds and check dams in the study area was carried out. The remote sensing data and GIS data was used to generate present land use, drainage pattern as well as slope and contour using 3-D technology. This analysis was carried out for diverting surplus water through proposed canal and pond. The result of the study indicate that if the surplus water from the Machhu dam is diverted to the unirrigated areas in Rajkot district, it will definitely improve the agricultural production due to availability of irrigation water through canal. The improvements in agricultural production will help to improve the economical condition of the farmers in the region. KeywordsRemote Sensing Satellite (IRS), Cartosat, LISS-III, LISS-IV Data, Digital Elevation Model (DEM), Canal Alignment, Geographic Information system (GIS), Surface Water Management

Effective lordosis: analysis of sagittal spinal canal alignment in cervical spondylotic myelopathy

Analysis of cervical sagittal deformity in patients with cervical spondylotic myelopathy (CSM) requires a thorough clinical and radiographic evaluation to select the most appropriate surgical approach. Angular radiographic measurements, which are commonly used to define sagittal deformity, may not be the most appropriate to use for surgical planning. The authors present a simple straight-line method to measure effective spinal canal lordosis and analyze its reliability. Furthermore, comparisons of this measurement to traditional angular measurements of sagittal cervical alignment are made in regards to surgical planning in patients with CSM. Twenty preoperative lateral cervical digital radiographs of patients with CSM were analyzed by 3 independent observers on 3 separate occasions using a software measurement program. Sagittal measurements included C2-7 angles utilizing the Cobb and posterior tangent methods, as well as a straight-line method to measure effective spinal canal lordosis from the dorsal-caudal aspect of the C2-7 vertebral bodies. Analysis of variance for repeated measures or Cohen 3-way (kappa) correlation coefficient analysis was performed as appropriate to calculate the intra- and interobserver reliability for each parameter. Discrepancies in angular and effective lordosis measurements were analyzed. Intra- and interobserver reliability was excellent (intraclass coefficient > 0.75, kappa > 0.90) utilizing all 3 techniques. Four discrepancies between angular and effective lordotic measurements occurred in which images with a lordotic angular measurement did not have lordosis within the ventral spinal canal. These discrepancies were caused by either spondylolisthesis or dorsally projecting osteophytes in all cases. Although they are reliable, traditional methods used to make angular measurements of sagittal cervical spine alignment do not take into account ventral obstructions to the spinal cord. The effective lordosis measurement method provides a simple and reliable means of determining clinically significant lordosis because it accounts for both overall alignment of the cervical spine as well as impinging structures ventral to the spinal cord. This method should be considered for use in the treatment of patients with CSM.

2-D Numerical Simulation of Flooding Effects Caused by South-to-North Water Transfer Project

Since the General Channel designed for the South-to-North Water Transfer Project in China has to cross many rivers and streams flowing from west to east, there are potentially serious effects additional flooding on the western side of the project alignment. Therefore, a 2-D numerical model for forecasting basin flood disasters was established and verified using historical flood data. The model was applied to researching the interaction between the proposed Project and flooding events for 5 streams in the Anyang River reach as a representative case study. Simulated results indicate that the model could correctly forecast the flood, submerged area and depths, and water surface elevations along the left side of the channel. The discharge capacity and location of hydraulic structures in the transfer canal alignment were analyzed. Then adjustments to the dimensions and positioning of proposed hydraulic structures were recommended at intersections, especially the addition of a channel to transfer flood water from one stream to another, which can effectively limit the sluice and protect the Anyang City from flooding.

GIS tools and the design of irrigation canals

AbstractThe previous decades have shown an incredible progress in information and computer technology for among others the optimal planning and use of water and soil resources, especially after the introduction of geographic information systems (GIS), satellite remote sensing and global positioning systems. GIS is able to integrate spatial and non‐spatial geographical data for the management and planning of land and water resources. These recent developments provide new ways to collect, store and retrieve, evaluate and analyse a broad variety of data for a wide range of irrigation management aspects. They also may assist in specific planning and decision‐making processes in irrigation through the input, spatial analysis and output of relevant information. Furthermore, if GIS is employed together with other computer applications it becomes more powerful in various fields, for example in the design and construction of irrigation and drainage canals.This article describes a procedure to design an irrigation canal and to optimise this design in view of earthwork. The procedure uses specific data processing and functions in GIS to facilitate the canal layout based on physical conditions and economic considerations. Digital information on topography, soils and natural drainage is used to identify the most suitable location for the canal. Digital elevation models (DEMs) are applied to prepare the horizontal and vertical canal alignment. Additionally, a computer model in Visual Basic has been developed to obtain an optimal hydraulic design by an iterative process. Next, the results of both packages are linked in a spreadsheet to optimise the canal layout in view of minimal earthwork. Copyright © 2004 John Wiley & Sons, Ltd.

Frost heave prevention measures for canal linings in China

Since the late 1970s, much experimental work has been carried out on the prevention of frost heave in canal linings in China. This paper presents the main research findings and engineering practices on this topic. After discussing the unevenly distributed heaving deformation on the canal section and the effect of soil moisture on the frost heave of the canal subsoil, the paper describes the measures taken in China to prevent the frost damage, including the proper selection of the canal alignment, the appropriate types of the cross section and the lining structures, the subsoil replacement with sand-gravel, the adoption of double lining (placing a membrane under the concrete slabs), the utilization of the insulation material and the prevention measures related to O & M. All these measures should be adopted in accordance with the local conditions.

A Planner's Viewpoint on Canal Alignment

A Planner's Viewpoint on Canal Alignment

Nuclear Excavation Design af a Transisthmian Sea-Level Canal

This paper presents an up-to-date analysis of the application of nuclear excavation technology to the design of a sea-level canal connecting the Atlantic and Pacific Oceans. This analysis is based on the technical data obtained to date under the auspices of the Atlantic-Pacific Interoceanic Canal Study Commission. Consideration is given in this paper to use of nuclear methods in the construction of a sea-level canal through the Darien region of Panama (Route 17) and the Atrato-Truando region of northwest Colombia (Route 25).The site data required for a comprehensive nuclear excavation design analysis of a proposed sea-level alignment include information pertaining to site topography, geology, hydrography, hydrology, meteorology, seismic propagation characteristics, bio-environmental conditions, and medico-ecology. These data are being used, together with data pertaining to nuclear explosive characteristics, cratering characteristics of pertinent geologic media, nuclear cratering detonation effects and channel design criteria, to develop an engineering-safety-cost analysis which is the basis for the nuclear excavation design.The results of geologic investigations to date along the 46-mile Route 17 alignment indicate that ~20 miles of the alignment through the Chucunaque Valley encounters a weak saturated clay shale while the balance of the excavation would be through relatively competent rock. In view of the unfavorable long-term slope stability characteristics of these shales, techniques were developed for using nuclear explosives to produce linear craters that have initially flat slopes of the order of 7 to 9°. Experiments indicate that nuclear excavation using a two-pass, triple-row array detonation system may offer a solution to this problem.A preliminary analysis of the topography and geology along the Route 25 sea-level canal alignment through northwest Colombia indicates that conventional excavation techniques, primarily hydraulic dredging, would be the most reasonable method of excavating ~78 miles of the 100-mile alignment. The remaining 23 miles of the alignment, through the Continental Divide, would be excavated using nuclear explosives.Studies in progress pertain to the safety aspects of using nuclear methods to construct a transisthmian sea-level canal, including consideration of seismic propagation, airblast acoustical wave phenomena, and radioactivity release. The results of such studies to date indicate that the potentially damaging effect on buildings from ground motions resulting from seismic propagations from the nuclear detonations will be the major factor in determining the maximum aggregate yield that can be detonated at any one time along the selected alignment.