摘要:
A data transmission protocol for use in an ATM-based point-to-multipoint passive optical network having a headend facility and a plurality of downstream network units, wherein downstream data is transmitted in serial data frames comprising one hundred eighty, fifty-four byte downstream slots, including two framing slots and one hundred seventy-eight ATM cell slots, which are transmitted every 125 .mu.sec for an overall downstream bit rate of 622.08 Mbps. Upstream data transmission is provided on a "permit" basis controlled by the headend based on monitoring ATM cell queue sizes at respective network units, wherein each downstream frame slot includes a one byte MAC overhead header field for transmitting upstream transmission permits allocated over twenty bit permit fields, for a total of seventy-two upstream permits allocated per downstream frame. Upstream data is transmitted from an individual network units in five hundred forty bit upstream data slots, each upstream slot having a preamble portion and a payload portion, i.e., with seventy-two upstream slots are transmitted every 125 .mu.sec, thereby forming upstream frames received at the headend at a data rate of 311.04 Mbps. Upstream bandwidth permits are based on a selected set of service priorities, wherein the respective permits specify which ATM service type is to be transmitted.
摘要:
A data transmission protocol for use in an ATM-based point-to-multipoint passive optical network having a headend facility and a plurality of downstream network units, wherein downstream data is transmitted in serial data frames comprising one hundred eighty, fifty-four byte downstream slots, including two framing slots and one hundred seventy-eight ATM cell slots, which are transmitted every 125 .mu.sec for an overall downstream bit rate of 622.08 Mbps. Upstream data transmission is provided on a "permit" basis controlled by the headend based on monitoring ATM cell queue sizes at respective network units, wherein each downstream frame slot includes a one byte MAC overhead header field for transmitting upstream transmission permits allocated over twenty bit permit fields, for a total of seventy-two upstream permits allocated per downstream frame. Upstream data is transmitted from an individual network units in five hundred forty bit upstream data slots, each upstream slot having a preamble portion and a payload portion,--i.e., with seventy-two upstream slots are transmitted every 125 .mu.sec, thereby forming upstream frames received at the headend at a data rate of 311.04 Mbps. Upstream bandwidth permits are based on a selected set of service priorities, wherein the respective permits specify which ATM service type is to be transmitted.
摘要:
A fluid dispensing apparatus is configured to dispense a predetermined volume of fluid, and includes a fluid reservoir to hold a fluid to be dispensed, a dispense tube to dispense the fluid, and an elevator mechanism. The fluid reservoir receives a fluid from a fluid supply. A dispense tube has a dispense outlet, and is connected to an outlet port on the fluid reservoir. The elevator mechanism changes a relative vertical displacement between the dispense outlet and the outlet port, such that the fluid is dispensed when the dispense outlet is lower than the outlet port, and not dispensed when the dispense outlet is higher than the outlet port.
摘要:
A fluid dispensing apparatus is configured to dispense a predetermined volume of fluid, and includes a fluid reservoir to hold a fluid to be dispensed, a dispense tube to dispense the fluid, and an elevator mechanism. The fluid reservoir receives a fluid from a fluid supply. A dispense tube has a dispense outlet, and is connected to an outlet port on the fluid reservoir. The elevator mechanism changes a relative vertical displacement between the dispense outlet and the outlet port, such that the fluid is dispensed when the dispense outlet is lower than the outlet port, and not dispensed when the dispense outlet is higher than the outlet port.
摘要:
Methods, devices, and systems for controlling a scanning tunneling microscope system are provided. In some embodiments, the methods, devices, and systems of the present disclosure utilize a control system included in or added to a scanning tunneling microscope (STM) to receive data characterizing a tunneling current between a tip of the scanning tunneling microscope system and a sample, to estimate, in real-time, a work function associated with the scanning tunneling microscope system, and to adjust, by a control system, a position of the tip based on an estimated work function. Associated systems are described herein.
摘要:
A patterned layer is formed by removing nanoscale passivating particle from a first plurality of nanoscale structural particles or by adding nanoscale passivating particles to the first plurality of nanoscale structural particles. Each of a second plurality of nanoscale structural particles is deposited on each of corresponding ones of the first plurality of nanoscale structural particles that is not passivated by one of the plurality of nanoscale passivating particles.
摘要:
A vehicular screen antenna includes a conductor extending on a dielectric, such as a window. The conductor is configured as a loop having entry and exit segments, the loop being positioned generally centrally on the dielectric. The entry and exit segments extend proximate each other from the loop towards a first edge of the dielectric and are oriented on the dielectric so as to extend generally vertically when the dielectric is fitted to a vehicle.
摘要:
A flexible endoscopic device including an elongate flexible member having opposite ends, an effector assembly mounted on one of the opposite ends of the flexible member, and a handle mounted on the end of the flexible member opposite the effector assembly. The handle includes a fastener for receiving a portion of the flexible member spaced from the end of the member opposite the effector assembly. The device also includes an actuator assembly extending through the flexible member and operatively connected to the effector assembly for actuating the effector.
摘要:
A vehicular screen antenna includes a conductor extending on a dielectric, such as a window. The conductor is configured as a loop having entry and exit segments, the loop being positioned generally centrally on the dielectric. The entry and exit segments extend proximate each other from the loop towards a first edge of the dielectric and are oriented on the dielectric so as to extend generally vertically when the dielectric is fitted to a vehicle.
摘要:
A patterned layer is formed by removing nanoscale passivating particle from a first plurality of nanoscale structural particles or by adding nanoscale passivating particles to the first plurality of nanoscale structural particles. Each of a second plurality of nanoscale structural particles is deposited on each of corresponding ones of the first plurality of nanoscale structural particles that is not passivated by one of the plurality of nanoscale passivating particles.