摘要:
An apparatus for propelling a projectile. A support structure has a propulsion structure pivotally connected thereto and is movable between an armed position and a disarmed position. In impulse delivery arrangement delivers an impulse force that propels the propulsion structure from the armed position to the disarmed position. A channel is configured to cause the projectile to be in biased contact with the propulsion structure upon the propulsion structure being in the armed position. Wherein, upon the impulse delivery arrangement delivering an impulse force propelling the propulsion structure from the armed position, the propulsion structure propels the projectile through and outwardly from the channel. The channel is selectively adjustable in X, Y, and Z planes to selectively guide the projectile in a generally predetermined direction, upon the projectile being propelled from the channel.
摘要:
A bone implant surgery system is used for simulating a dental surgical procedure having a display that shows placing a simulated bone implant at a simulated implant site on a living body by using a simulated surgical tool holding the simulated bone implant. At least one hand-held haptic device is used to control the surgical tool and at least one controller is specifically configured to cause movement of the surgical tool on the display based on motions of the haptic device and to cause haptic feedback to a user holding the haptic device depending on the position of the surgical tool on the display. A user may then review and evaluate the results of the surgical simulation.
摘要:
Devices and methods for controlling myopia are provided. The devices and methods relate to the inventors discovery of the relationship between near work, the forces applied to the eye by the eyelids and myopia. The devices include a contact lens comprising a region that disperses force applied to the eye by an eyelid. The devices also include a device designed by measuring first wavefront aberrations of an eye before pre-near work and measuring second measured wavefront aberrations of the eye post-near work. The methods include a method for controlling myopia including identifying optical changes associated with near work and correcting the optical changes with an optical device.
摘要:
Efficiently controlled converter system embodiments are provided to operate in different operational modes. In a first operational PWM mode, first and second transistors are switched with a feedback-controlled duty cycle to thereby realize an inductor current that maintains a system output voltage. In a second operational PFM mode, after the output voltage decays to a lower threshold over a decay time, the control and synchronous transistors are driven a sufficient number of times to raise the output voltage to an upper threshold. The systems are controlled to efficiently transition between the first and second operational modes. For example, a converter system preferably transitions to the second PFM operational mode when current peaks of the inductor current drop below a predetermined current threshold and the system preferably transitions to the first PWM operational mode when the output voltage drops to a predetermined reference voltage.
摘要:
Systems and methods utilize a distributed server network to allow for the optimization of the upload of a data stream from a computing device. Performance metrics are estimated for different network paths from the computing device to a variety of entry servers in the distributed server network. Based on the estimated performance metrics, one or more entry servers are then selected to receive the data stream from the computing device. As a result, the systems and methods described herein allow for high quality upload performance which addresses the first mile vulnerability issues of the data stream. The distributed server network can then transmit copies of the data stream in real-time to other computing devices.
摘要:
Systems and methods described herein utilize a distributed server network to allow for the real-time distribution of copies of a data stream uploaded from a computing device. The uploaded data stream corresponds to an environment surrounding a user (exam taker) of the computing device during execution of a testing routine for an examination. Providing copies of the data stream in real-time allows proctors as well as other test assessment authorities to ‘peek in’ on the exam taker's environment during the exam. As a result, the environment surrounding the exam taker can be monitored in real-time to determine whether any visual or audio activity in the environment constitutes activity not in accordance with the exam protocol. Following an affirmative determination that the exam taker violated an exam taking protocol, a proctor or other test assessment authority can then make a final or early decision regarding disciplinary action.
摘要:
Systems and methods described herein provide for administering and proctoring of a secure online examination utilizing a ‘cloud’ computing environment. The cloud computing environment provides scalable, shared computing resources such as processing, memory, communications, storage and other hardware and software resources associated with the online examination. The computing resources provided by the cloud computing environment can be provisioned dynamically to match the requirements of the particular computing tasks carried out at the client and/or server level during the administration of the examination.
摘要:
A bone implant surgery system is used for simulating a dental surgical procedure having a display that shows placing a simulated bone implant at a simulated implant site on a living body by using a simulated surgical tool holding the simulated bone implant. At least one hand-held haptic device is used to control the surgical tool and at least one controller is specifically configured to cause movement of the surgical tool on the display based on motions of the haptic device and to cause haptic feedback to a user holding the haptic device depending on the position of the surgical tool on the display. A user may then review and evaluate the results of the surgical simulation.
摘要:
In accordance with one embodiment of the present invention, there is provided a submersible pump that includes a pump housing forming a main compartment for receiving a pump impeller and having liquid entrance and exit openings in said main compartment, and an impeller mounted in the main compartment. The pump housing is adapted for submersion in a body of liquid whose level is to be controlled, and a sealed auxiliary compartment is formed as an integral part of the housing and located to be at least partially submerged in the liquid body. A drive motor is coupled to the impeller for rotating the impeller to eject liquid from the main compartment through the exit opening. An electric-field sensor is mounted in the sealed auxiliary compartment for detecting the elevation of the surface of the liquid body adjacent the sealed auxiliary compartment. At least one controllable switch is connected in the power supply line for controlling the supply of power to the drive motor, and the electric-field sensor is connected to the controllable switch for opening and closing the switch in response to changes in the detected elevation of the surface of the liquid body adjacent the outer surface of the sealed auxiliary compartment.