1471 results about "Positive feedback" patented technology

A recommendation system uses feedback from users on specific item recommendations to assess the quality of the recommendation rules used to generate such recommendations. The feedback may be explicit (e.g., a user rates a particular recommended item), implicit (e.g., a user purchases a recommended item), or both. The system may use these assessments to modify the degree to which particular recommendation rules are used to generate recommendations. For instance, if a particular recommendation rule leads to negative feedback relatively frequently, the system reduce or terminate its reliance on the rule. In some embodiments, the system may also increase its reliance on recommendation rules that tend to produce positive feedback.

Ultrasound contrast agents are used to enhance imaging and facilitate HIFU therapy in four different ways. A contrast agent is used: (1) before therapy to locate specific vascular structures for treatment; (2) to determine the focal point of a HIFU therapy transducer while the HIFU therapy transducer is operated at a relatively low power level, so that non-target tissue is not damaged as the HIFU is transducer is properly focused at the target location; (3) to provide a positive feedback mechanism by causing cavitation that generates heat, reducing the level of HIFU energy administered for therapy compared to that required when a contrast agent is not used; and, (4) to shield non-target tissue from damage, by blocking the HIFU energy. Various combinations of these techniques can also be employed in a single therapeutic implementation.

A translation enhancer-driven positive feedback vector system is disclosed which is designed to facilitate identification of a Translational Enhancer Element (TEE) and to provide a means for overexpression of gene products. The system exploits both transcriptional and translational approaches to control the expression levels of genes and / or gene products. Methods are also disclosed for screening libraries of random nucleotide sequences to identify translational elements and for overproduction of proteins, which have uses in both research and industrial environments.

Systems and methods for providing real-time feedback to karaoke users are provided. The systems and methods for providing users with real-time feedback while they are singing karaoke generally relate to receiving the user's vocals, determining whether the user is singing on key / pitch and providing real-time feedback to the user while the karaoke song is being sung. The feedback will be positive feedback if user is on key / pitch and it will be negative feedback if user is off key / pitch. For example, the feedback signal if the user is singing too low can be an exaggerated low signal of the user's own voice. This will encourage the user to sing at a higher pitch.

Photosensor circuits include a relay coil configured to control application of an alternating current (AC) power source to a load. A pulse width modulator circuit is configured to generate a pulse width modulated signal having a pulse width that varies responsive to an average voltage across the relay coil. A drive transistor controls the average voltage across the relay coil responsive to the pulse width modulated signal. A photo control circuit controls application of the pulse width modulated signal to the drive transistor responsive to a detected light level. A half-wave rectifier provide a power signal to the pulse width modulator circuit and the photo control circuit during one of the halves of the line cycle of the AC power source. The photo control circuit includes a phototransistor. A low pass filter circuit filters the output current of the phototransistor to provide a light level signal voltage. A select transistor couples the pulse width modulated signal to the drive transistor during one of the halves of the line cycle of the AC power source responsive to the light level signal voltage having a selected level. A capacitor coupled between the second terminal of the phototransistor and the neutral bus modulates an amount of positive feedback through the first terminal of the phototransistor proportional to a current flowing through the relay coil to provide hysteresis to control of the relay coil by the photosensor circuit.