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1.
J Med Syst ; 39(12): 194, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26490152

RESUMEN

As cloud computing and wearable devices technologies mature, relevant services have grown more and more popular in recent years. The healthcare field is one of the popular services for this technology that adopts wearable devices to sense signals of negative physiological events, and to notify users. The development and implementation of long-term healthcare monitoring that can prevent or quickly respond to the occurrence of disease and accidents present an interesting challenge for computing power and energy limits. This study proposed an adaptive sensor data segments selection method for wearable health care services, and considered the sensing frequency of the various signals from human body, as well as the data transmission among the devices. The healthcare service regulates the sensing frequency of devices by considering the overall cloud computing environment and the sensing variations of wearable health care services. The experimental results show that the proposed service can effectively transmit the sensing data and prolong the overall lifetime of health care services.


Asunto(s)
Nube Computacional , Redes de Comunicación de Computadores/instrumentación , Tecnología de Sensores Remotos/instrumentación , Telemedicina/instrumentación , Tecnología Inalámbrica/instrumentación , Algoritmos , Humanos
2.
Sensors (Basel) ; 12(4): 4431-46, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22666038

RESUMEN

This paper proposes the Top-View Transformation Model for image coordinate transformation, which involves transforming a perspective projection image into its corresponding bird's eye vision. A fitting parameters searching algorithm estimates the parameters that are used to transform the coordinates from the source image. Using this approach, it is not necessary to provide any interior and exterior orientation parameters of the camera. The designed car parking assistant system can be installed at the rear end of the car, providing the driver with a clearer image of the area behind the car. The processing time can be reduced by storing and using the transformation matrix estimated from the first image frame for a sequence of video images. The transformation matrix can be stored as the Matrix Mapping Table, and loaded into the embedded platform to perform the transformation. Experimental results show that the proposed approaches can provide a clearer and more accurate bird's eye view to the vehicle driver.

3.
Sensors (Basel) ; 12(5): 6415-33, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22778650

RESUMEN

A road sign recognition system based on adaptive image pre-processing models using two fuzzy inference schemes has been proposed. The first fuzzy inference scheme is to check the changes of the light illumination and rich red color of a frame image by the checking areas. The other is to check the variance of vehicle's speed and angle of steering wheel to select an adaptive size and position of the detection area. The Adaboost classifier was employed to detect the road sign candidates from an image and the support vector machine technique was employed to recognize the content of the road sign candidates. The prohibitory and warning road traffic signs are the processing targets in this research. The detection rate in the detection phase is 97.42%. In the recognition phase, the recognition rate is 93.04%. The total accuracy rate of the system is 92.47%. For video sequences, the best accuracy rate is 90.54%, and the average accuracy rate is 80.17%. The average computing time is 51.86 milliseconds per frame. The proposed system can not only overcome low illumination and rich red color around the road sign problems but also offer high detection rates and high computing performance.

4.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): o1558, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21836972

RESUMEN

In the title compound, 2C(18)H(16)N(2)O(2)·H(2)O, the dihedral angles between the quinoline rings and the benzene rings in the two independent acetamide mol-ecules are 80.09 (5) and 61.23 (5)°. The crystal packing is stablized by O-H⋯N and N-H⋯O hydrogen bonds between the acetamide and water mol-ecules.

5.
Rev Sci Instrum ; 78(6): 066103, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17614647

RESUMEN

In this study, a laser linear encoder with three degrees of freedom (3-DOFs) based on diffraction and interference was developed to measure the linear displacement and two angular errors of a linear moving stage. Parts of the linear motion errors induced from the two angular errors can be calculated by this prototype 3-DOF laser encoder. It was an effective method for online error calculation and compensation to improve precision stage performance. This new function was superior to other laser encoders. The verification results showed that the resolution is 20 nm. It detected displacements relative to an external grating scale with accuracy of about +/-150 nm for a measuring range of +/-1 mm, and detected the angular errors with related accuracy of about +/-1 arc sec for a measuring range of +/-100 arc sec.


Asunto(s)
Imagenología Tridimensional/instrumentación , Rayos Láser , Movimiento (Física) , Refractometría/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Imagenología Tridimensional/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Huan Jing Ke Xue ; 36(4): 1249-55, 2015 Apr.
Artículo en Zh | MEDLINE | ID: mdl-26164897

RESUMEN

The sampling was carried out in Sanmenxia hydrological station, Xiaolangdi hydrological station and Huayuankou hydrological station from November 2011 to October 2012. The impact of the runoff-sediment control of the Xiaolangdi reservoir on DOC transport,was analyzed. The results were as follows. DOC contents in Sanmenxia station, Xiaolangdi station and Huayuankou station were 1.97-2.71 mg-L(-1), 1.87-2.76 mg x L(-1) and 2.07-2.93 mg x L(-1), respectively, during the normal operation period of Xiaolangdi Reservoir and Sanmenxia reservoir, and the DOC content in the three reservoirs had obvious seasonal change. DOC contents in the three stations were 2.14-3.32 mg x L(-1), 2.21-2.84 mg x L(-1) and 2.11-2.84 mg x L(-1), respectively, during the runoff-sediment control, and the DOC content in the sediment-releasing period of reservoir was higher than that in the water-releasing period of reservoir. DOC content had no significant correlation with TSS and flow either during the normal operation or during the water-sediment regulation of the reservoir. But the DOC content had significant correlation with water temperature during the normal operation of the reservoir. DOC flux in Sanmenxia station was similar to that in Xiaolangdi station from November to March. DOC flux in Sanmenxia station was obviously less than that in Xiaolangdi station from April to July. And the DOC flux in Sanmenxia station was much higher than that in Xiaolangdi station from August to October. The result showed that DOC was retained from August to October by Xiaolangdi reservoir and discharged from Xiaolangdi reservoir from April to July. The yearly DOC fluxes were 8.6 x 10(10), 9.0 x 10(10) and 9.7 x 10(10) g respectively in Sanmenxia station, Xiaolangdi station and Huayuankou station. The DOC flux of Sanmenxia station was the highest in September, which accounted for 22.0% of the yearly DOC flux, and the DOC flux of Xiaolangdi station was the highest in June, which accounted for 17.6% of the yearly DOC flux. The DOC flux of Huayuankou station was the highest in July, which accounted for 16.7% of the yearly DOC flux. DOC fluxes during the runoff-sediment regulation accounted for 14.7% and 13.8% of the yearly DOC flux respectively in Xiaolangdi station and Huayuankou station, but the DOC fluxes during the runoff-sediment regulation accounted for only 3.6% of the yearly DOC flux in Sanmenxia station.


Asunto(s)
Sedimentos Geológicos , Movimientos del Agua , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Hidrología , Temperatura , Agua
7.
Comput Med Imaging Graph ; 28(1-2): 13-20, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15127745

RESUMEN

An algorithm for reconstructing magnetic resonance cholangiography (MRC) biliary structure is proposed. The processing of MRC data can be divided into four phases. In the first phase, the region of interest (ROI) containing the liver and biliary ducts is extracted from the original volume data based on human anatomy and B-spline curve. The second phase involves segmenting the biliary ducts from the region identified in the previous phase. Because the image of biliary portion is brighter than the liver, the segmentation is started by choosing the brightest pixel in the ROI as the seed for 3D region growing. This procedure could be executed many times, depending on the provided stopping condition. In the third phase, the segmented biliary duct regions are traced to construct the biliary tree. An automated 3D tracking algorithm is proposed for this phase. This 3D tracking algorithm estimates the coordinates of the points along the medial axis of each biliary duct branch. The cross sections associated with the points along the medial axis are also calculated approximately during the tracking process. The biliary tree data structure is constructed in this phase. The biliary tree is reconstructed and rendered in the last phase. Although the proposed algorithm takes a longer time compared with the conventional approach, the reconstructed biliary tree 3D structure can provide more clearly image. A concise representation for the biliary tree can be achieved with the proposed method and provide both quantitative and structural information for clinical reference.


Asunto(s)
Conductos Biliares/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Algoritmos , Humanos
8.
Comput Med Imaging Graph ; 28(1-2): 21-31, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15127746

RESUMEN

Medical diagnosis can benefit from the complementary information in different modality images. Multi-modal image registration and fusion is an essential task in numerous three-dimensional (3D) medical image-processing applications. Registered images are not only providing more correlative information to aid in diagnosis, but also assisting with the planning and monitoring of both surgery and radiotherapy. This research is directed at registering different images captured from Computed Tomography (CT) and Magnetic Resonance (MR) imaging devices, respectively, to acquire more thorough information for disease diagnosis. Because MR bone model segmentation is difficult, this research used a 3D model obtained from CT images. This model accomplishes image registration by optimizing the gradient information accumulated around the bony boundary areas with respect to the 3D model. This system involves pre-processing, 2D segmentation, 3D registration, fusion and sub-system rendering. This method provides desired image operation, robustness verification, and multi-modality spinal image registration accuracy. The proposed system is useful in observing the foramen and nerve root. Because the registration can be performed without external markers, a better choice for clinical usage is provided for lumbar spine diagnosis.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Médula Espinal/anatomía & histología , Médula Espinal/diagnóstico por imagen , Columna Vertebral/anatomía & histología , Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Humanos , Raíces Nerviosas Espinales/anatomía & histología , Raíces Nerviosas Espinales/diagnóstico por imagen
9.
Environ Int ; 52: 66-74, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23291099

RESUMEN

Enshi prefecture of Hubei Province is well known for human selenium (Se) poisoning in the early 1960s in China. Sporadic cases of Se poisoning in livestocks are still being found. In this study, Se levels in water, cropland soils and various crops from high-Se areas of Enshi were measured to investigate the distribution and bioavailability of Se in the environments, as well as probable daily intake (PDI) of Se for local residents. The total Se in surface water ranged from 2.0 to 519.3µg/L with a geometric mean of 46.0±127.8 µg/L (n=48), 70.5-99.5% of which was present in the form of Se(VI). The soil Se concentration varied from 2.89 to 87.3 µg/g with a geometric mean of 9.36±18.6 µg/g (n=45), and most of Se was associated with organic matter (OM-Se). The total Se in rice, corn, and vegetable samples were 2.11±2.87 µg/g (n=21), 3.76±11.6 µg/g (n=16), and 2.09±3.38 µg/g (n=25), respectively. Stream water Se is likely leached from carbonaceous shale and mine wastes, leading to Se accumulation in paddy soils. OM-Se may play an important role in Se uptake by rice plant in high-Se area of Enshi. The PDI of Se is approximately 2144 µg/day, and Se concentration in blood is estimated at about 3248 µg/L, posing a potential chronic Se poisoning risk to local residents. Cereal consumption (48.5%) makes a great contribution to human daily Se intake, followed by vegetables (36.6%), meats (8.5%), and drinking water (6.4%). However, when assessing health risk on human in high-Se areas, the contribution of drinking water to daily Se intake cannot be ignored due to high Se content and dominant Se(VI) species. Local inhabitants should be advised not to grow crops in high-Se lands or irrigate using high-Se water. If possible, they should drink pipe water and consume foods mixed with those from outside the high-Se areas.


Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/análisis , Selenio/análisis , China , Dieta/estadística & datos numéricos , Ambiente , Monitoreo del Ambiente , Humanos , Oryza/química , Medición de Riesgo , Ríos/química , Selenio/envenenamiento , Suelo/química , Verduras/química , Zea mays/química
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