Abstract: A laser tuning system includes an optical transmitter having a tunable laser that transmits optical signals at various wavelengths to an optical fiber through an optical component, which attenuates a range of wavelengths of the optical signal. An optical detector detects optical returns that have been reflected from the fiber at points beyond the optical component. A tuning control module analyzes the optical returns in order to provide a tuning value for tuning the laser to a desired wavelength. As an example, the laser may be tuned in order to maximize or otherwise increase the amount of optical power passing through the optical component.

Abstract: An optical transmission system transmits an optical signal over an optical path. Reflections of the optical signal are received at an optical detector which generates an analog reflection signal. The analog reflection signal includes both a desired portion and an undesired portion. Correlators of an OTDR system generate correlation values based on the analog reflection signal. A subset of the correlation values are associated with locations of the optical path that cause the reflections that result in the undesired portion of the reflected signal. A filter uses these correlation values to generate a cancellation signal that is subtracted from the analog reflection signal, reducing the undesired portion of the signal that must be processed.

Abstract: Methods, systems, and apparatus for automatically identifying rogue Optical Network Unit (ONU) are disclosed. In one aspect, an Optical Line Terminal (OLT) determines dark power on a fiber optic link over a period of time. For a given ONU, the OLT determines an optical power of high signals and an optical power of low signals received over the fiber optic link during a timeslot assigned to the given ONU, determines a modified optical power of the high signals and a modified optical power of the low signals based on differences between the optical power of the respective signals and the dark power, determines an extinction ratio based on a ratio of the modified optical power of the high signals relative to the modified optical power of the low signals, and identifies the given ONU as a rogue ONU when the extinction ratio is outside of a specified range.

Abstract: A method of making a special track assembly for supporting a train, including providing a special track segment, and attaching a number of ribs made of a resilient material to exterior surfaces of the special track segment. Adjacent ones of the ribs are spaced apart from each other by predetermined distances to define gaps therebetween respectively. The method also includes attaching one or more wall portions of the resilient material to the ribs, for bridging each gap to at least partially define a number of cavities between the adjacent ribs respectively. Each wall portion is deflectable for dissipating energy transmitted by movement of the special track segment relative to the supporting material which supports the special track assembly.

Abstract: An apparatus for heating a liquid is described. The apparatus includes a housing. A liquid reservoir is contained within the housing. A fluid circuit conveys liquid from the reservoir to a dispenser. A thermal energy storage unit is contained within the housing and disposed to be in thermal contact with the fluid circuit. The thermal energy storage unit is constructed and arranged to heat liquid as it passes through the fluid circuit. The thermal energy storage unit can include a phase change material or a combination of a phase change material and a high thermal conductivity material.

Abstract: This invention provides an improved implantable tibial component comprising an implantable tibial base containing two separate, opposed raised walls which engage oppositely configured recesses in the lower surface of a removable hard polymeric condylar articulating surface insert. The locking mechanism which holds the insert within the base provides a means by which the insert can be locked within the base in a secure fashion. The locking mechanism further provides a means by which the insert can be removed from the implanted tibial base in a simple fashion by raising the anterior end of the insert over the top of the anterior wall on the edge of the tibial base and sliding the insert anteriorly out of the posterior raised walls which also extend along the medial and lateral edges of the tibial base.