摘要:
A system and method for using learned discriminative models to segment a border of an anatomical structure in a three dimensional (3D) image is disclosed. A discriminative probability model is computed for each voxel in the 3D image. Thresholding is performed on each discriminative probability model. One or more two dimensional (2D) slices of the thresholded 3D image along X-Y planes are obtained. Seed regions are selected in the 2D slices. Morphological region growing is performed on the selected seed regions. An initial 3D segmentation is obtained. Boundary evolution is performed on the initial 3D segmentation. The segmented anatomical structure is removed. in the original 3D image.
摘要:
The present invention provides methods and apparatuses for controlling a gain of an optical fiber amplifier. Gain circuitry operates in an opened loop configuration and uses a predetermined function relating a power variation of at least one wavelength region with a pump power adjustment for at least one optical pump. Two approximate linear relationships between the input signal power variations and the required pump power adjustments are utilized in controlling the Raman fiber amplifier. Each approximate linear relationship includes at least one linear coefficient that relates a power variation for a specific wavelength region and a power adjustment of a specific Raman pump. The dynamic gain control technique is applicable to an Erbium-doped fiber/waveguide amplifier. Also, a dynamic gain control technique controls a backward-pumped Raman amplifier, in which the power variation is determined at one geographical location and the optical pumps are controlled at another geographical location.
摘要:
A method for automatically scheduling tasks in whole-body computer aided detection/diagnosis (CAD), including: (a) receiving a plurality of tasks to be executed by a whole-body CAD system; (b) identifying a task to be executed, wherein the task to be executed has an expected information gain that is greater than that of each of the other tasks; (c) executing the task with the greatest expected information gain and removing the executed task from further analysis; and (d) repeating steps (b) and (c) for the remaining tasks.
摘要:
The present invention provides methods and apparatuses for controlling a gain of a bidirectionally-pumped Raman fiber amplifier having both forward optical pumps and backward optical pumps. The overall gain is controlled by adjusting the forward optical pumps, while the power levels of the backward optical pumps are essentially fixed. Gain circuitry operates in an opened loop configuration and uses a predetermined function relating a power variation of at least one wavelength region with a pump power adjustment for at least one forward optical pump. Two approximate linear relationships between the input signal power variations and the required pump power adjustments are utilized in controlling the Raman fiber amplifier. Each approximate linear relationship includes at least one linear coefficient that relates a power variation for a specific wavelength region and a power adjustment of a specific Raman pump.
摘要:
An electro-mechanical actuator (21) includes a reverse transfer system ball-screw (20). The actuator broadly includes a frame (22), a nut (43) mounted on the frame, at least one magnet (59) mounted on the nut, at least one coil (55) mounted on the frame, the coil being adapted to be selectively supplied with current to cause the nut to rotate within the frame, a rotary feedback device (80), and a screw (44) arranged within the nut for rotational and axial movement relative thereto. The screw and nut both have cooperative ball recesses (72, 74) that define a ball path in which a plurality of balls (73) are mounted. The ball recirculation path is provided in the screw. A rod (23) is connected to the screw for movement therewith. Relative rotation between the nut and screw will cause the screw and rod to move axially relative to the frame.
摘要:
A multi-band hybrid amplifier is disclosed for use in optical fiber systems. The amplifier uses Raman laser pumps and semiconductor optical amplifiers in series to produce a relatively level gain across the frequency range of interest. Multiple Raman pumps are multiplexed before coupling into the fiber. The Raman amplified optical signal may be demultiplexed and separately amplified by the SOAs before re-multiplexing. Gain profiles of the Raman pumps and the SOAs are selected to compensate for gain tilt and to alleviate the power penalty due to cross-gain modulation in the SOAs. The disclosed hybrid amplifier is especially useful in coarse wavelength division multiplexing (CWDM) systems.
摘要:
A method of detecting breast masses and calcifications in digitized images, includes providing a plurality of 2-dimensional (2D) digital X-ray projectional breast images acquired from different viewing angles, extracting candidate lesions and 2D features from said 2D projectional images, computing spicularity characteristics of said candidate lesions, including location, periodicity, and amplitude, applying learning algorithms to said candidate lesions to predict a probability of malignancy of said lesion, receiving from said learning algorithm a probability map of detections for each breast image, said detections comprising associating pixels with a probability of being associated with a malignancy, creating a synthetic 2D slice for each X-ray image wherein malignant regions are indicated by ellipses on a non-malignant background, and constructing a synthetic 3-dimensional (3D) image volume from said 2D synthetic slices.
摘要:
The present invention provides methods and apparatuses for controlling a gain of an optical fiber amplifier. Gain circuitry operates in an opened loop configuration and uses a predetermined function relating a power variation of at least one wavelength region with a pump power adjustment for at least one optical pump. Two approximate linear relationships between the input signal power variations and the required pump power adjustments are utilized in controlling the Raman fiber amplifier. Each approximate linear relationship includes at least one linear coefficient that relates a power variation for a specific wavelength region and a power adjustment of a specific Raman pump. The dynamic gain control technique is applicable to an Erbium-doped fiber/waveguide amplifier. Also, a dynamic gain control technique controls a backward-pumped Raman amplifier, in which the power variation is determined at one geographical location and the optical pumps are controlled at another geographical location.
摘要:
The present invention provides methods and apparatuses for controlling a gain of a bidirectionally-pumped Raman fiber amplifier having both forward optical pumps and backward optical pumps. The overall gain is controlled by adjusting the forward optical pumps, while the power levels of the backward optical pumps are essentially fixed. Gain circuitry operates in an opened loop configuration and uses a predetermined function relating a power variation of at least one wavelength region with a pump power adjustment for at least one forward optical pump. Two approximate linear relationships between the input signal power variations and the required pump power adjustments are utilized in controlling the Raman fiber amplifier. Each approximate linear relationship includes at least one linear coefficient that relates a power variation for a specific wavelength region and a power adjustment of a specific Raman pump.
摘要:
Various attributes for medical CAD analysis used alone or in combination are disclosed, including: (1) using medical sensor data and context information associated with the configuration of the medical system to provide recommendations for further acts to be performed for more accurate or different diagnosis, (2) recommending further acts to be performed and providing an indication of the importance of the further act for further diagnosis, (3) distributing the computer-assisted diagnosis software and/or database over multiple systems, and (4) transmitting patient data to a remote system for CAD diagnosis and using the results of the CAD diagnosis at the remote facility.