Abstract: The method and apparatus for increasing the efficiency of a low-temperature or high temperature heating system, comprising a primary heat releasing unit (i.e. cogeneration unit with fuel cell (FC) or internal combustion engine (ICE)) for co-generation of the heat and power, and at least one secondary heat releasing unit (i.e. heat pump (HP)) for utilization of at least one of the available waste/renewable energy heat sources (HS) from the ambient (A), where the heat generated by said heat pump is preferably used for preheating the heat transfer medium in the return line of the closed loop heating system, wherein a primary heat releasing unit is used to heat the heat transfer medium to the required temperature level of the heat distribution network. The apparatus according to the invention may comprise one or more heat pumps (HP) of the same or different types, and one or more primary heat releasing units in serial, parallel or cascade connection circuits.

Abstract: An optical system having an optical sensor with an ultra-short FP cavity, and a low-resolution optical interrogation system coupled to the optical sensor and operational to send light signals and receive light signals to and from the optical sensor is disclosed. The optical system may operate in a wavelength range including the visible and near-infrared range. Optical assemblies and methods of interrogating optical sensors are provided, as are numerous other aspects.

Abstract: The invention relates to a method and apparatus for low temperature waste heat utilization. In the scope of the hot water plant (HWP) there are few low temperature sources, which cannot be used by heat consumer (HC) directly.

Abstract: An optical wavelength sweeping apparatus is disclosed. The optical wavelength sweeping apparatus includes a laser diode having an active region including a thickness of less than 1 ?m, a cross-section of less than 7 ?m2, and a ratio of active region volume to total laser diode volume of less than 1/300, and a pulse generator coupled to the laser diode. The pulse generator is configured and operable to provide a current drive pulse to the laser diode to selectively and rapidly heat the active region and immediate vicinity to provide a peak increase in temperature of 30° C. or more at an end of the current pulse and to perform a wavelength sweep of emitted optical radiation which is greater than 5 nm. Methods of driving a laser diode and optical systems are disclosed, as are other aspects.

Abstract: Fast near-lossless compression includes four steps: voxelization of the 3D geometry, decomposing the 3D voxel space into consecutive slices, encoding each slice with chain codes, and compressing the chain code with entropy coding. The decompression works by applying the aforementioned steps in inverse order. Smoothing over the voxels' centers is applied afterwards in order to reconstruct the input 3D points. Optionally 3D mesh is reconstructed over the approximate point cloud in order to obtain the original geometric object. The quality of the compression/decompression is controlled by resolution of the 3D voxel grid.

Abstract: An optical system having an optical sensor with an ultra-short FP cavity, and a low-resolution optical interrogation system coupled to the optical sensor and operational to send light signals and receive light signals to and from the optical sensor is disclosed. The optical system may operate in a wavelength range including the visible and near-infrared range. Methods of interrogating optical sensors are provided, as are numerous other aspects.

Abstract: An optical wavelength sweeping apparatus having a laser diode with an active region, and a coupled pulse generator is disclosed. The pulse generator is configured and operable to provide current drive pulses of relatively short duration and high amplitude to the laser diode to selectively and rapidly heat the active region and the immediate vicinity and produce a rapid wavelength sweep of emitted optical radiation. Methods of driving a laser diode, and measurement systems are disclosed, as are other aspects.

Abstract: Methods and apparatus for lossless LiDAR LAS file compression and decompression are provided that include predictive coding, variable-length coding, and arithmetic coding. The predictive coding uses four different predictors including three predictors for x, y, and z coordinates and a constant predictor for scalar values, associated with each LiDAR data point.

Abstract: Optical fiber sensors adapted to measure strain or pressure are disclosed. The optical fiber sensor has a lead-in optical fiber having an end surface at a forward end, and a first optical element having a body with an outer dimension, Do, a front end surface coupled to the lead-in optical fiber, a pedestal including a retracted surface that is spaced from the front end surface, the retracted surface at least partially defining an optical cavity, a gutter surrounding the pedestal, the gutter having a gutter depth defining an active region of length, L, the first optical element further exhibiting L/Do?0.5. Also provided are systems including the optical fiber sensor, and methods for manufacturing and using the optical fiber sensor. Numerous other aspects are provided.

Abstract: An optical fuse device adapted to be placed in between ends of lead-in fibers of an optical fiber line. The optical fuse device has a destructible region having a core, the destructible region including a light absorbing material adapted to heat and destroy the core upon application of a light intensity greater than a predetermined threshold. Optical fiber lines including the optical fuse device and methods of manufacturing the optical fuse device are provided. Numerous other aspects are provided.

Abstract: An optical wavelength sweeping apparatus having a laser diode with an active region, and a coupled pulse generator is disclosed. The pulse generator is configured and operable to provide current drive pulses of relatively short duration and high amplitude to the laser diode to selectively and rapidly heat the active region and the immediate vicinity and produce a rapid wavelength sweep of emitted optical radiation. Methods of driving a laser diode, and measurement systems are disclosed, as are other aspects.

Abstract: An in-line optical device adapted to be bonded in between ends of an optical fiber line is disclosed. The in-line optical device has an inner optical field interaction region, an outer support structure, and at least one radial opening. In some embodiments, a void region substantially surrounds the inner optical field interaction region. Systems including the in-line optical device and methods of making and using the in-line optical device are provided. Numerous other aspects are provided.

Abstract: Optical fiber sensors adapted to measure strain or pressure are disclosed. The optical fiber sensor has a lead-in optical fiber having an end surface at a forward end, and a first optical element having a body with an outer dimension, Do, a front end surface coupled to the lead-in optical fiber, a pedestal including a retracted surface that is spaced from the front end surface, the retracted surface at least partially defining an optical cavity, a gutter surrounding the pedestal, the gutter having a gutter depth defining an active region of length, L, the first optical element further exhibiting L/Do?0.5. Also provided are systems including the optical fiber sensor, and methods for manufacturing and using the optical fiber sensor. Numerous other aspects are provided.

Abstract: An optical fuse device adapted to be placed in between ends of lead-in fibers of an optical fiber line. The optical fuse device has a destructible region having a core, the destructible region including a light absorbing material adapted to heat and destroy the core upon application of a light intensity greater than a predetermined threshold. Optical fiber lines including the optical fuse device and methods of manufacturing the optical fuse device are provided. Numerous other aspects are provided.

Abstract: Methods of manufacturing optical devices are disclosed. The method includes providing a structure-forming fiber bonded to at least one other optical component, the structure-forming fiber having a preferentially-etchable portion including at least one radial etching boundary and at least one axial etching boundary, and etching the preferentially-etchable portion to the radial and axial etching boundaries to produce a precise optical structure. The preferentially-etchable portion may be removed through one or more radial openings in the structure-forming fiber. Numerous other aspects are provided.

Abstract: Opto-electronic signal processing systems, apparatus and methods to extract a measured parameter from one or more interrogated optical sensors are disclosed. The apparatus includes an integrated laser module, an electronic control and processing unit, an optical coupling element, and one or more light receivers. Light is reflected back from the optical sensor through the optical coupling element to the light receiver(s). The electronic control and processing unit controls the wavelength of the integrated laser module using thermal control and, at the same time, detecting the wavelength of the integrated laser module using a wavelength selective element of the integrated laser module. According to the method, a wavelength sweep from the integrated laser module wavelength is swept, simultaneously measured and stored in memory of the electronic control and processing unit.

Abstract: Optical fiber sensors adapted to measure strain or pressure are disclosed. The optical fiber sensor has a lead-in optical fiber having an end surface at a forward end, and a first optical element having a body with an outer dimension, Do, a front end surface coupled to the lead-in optical fiber, a pedestal including a retracted surface that is spaced from the front end surface, the retracted surface at least partially defining an optical cavity, a gutter surrounding the pedestal, the gutter having a gutter depth defining an active region of length, L, the first optical element further exhibiting L/Do?0.5. Also provided are systems including the optical fiber sensor, and methods for manufacturing and using the optical fiber sensor. Numerous other aspects are provided.

Abstract: Methods of manufacturing optical devices are disclosed. The method includes providing a structure-forming fiber bonded to at least one other optical component, the structure-forming fiber having a preferentially-etchable portion including at least one radial etching boundary and at least one axial etching boundary, and etching the preferentially-etchable portion to the radial and axial etching boundaries to produce a precise optical structure. The preferentially-etchable portion may be removed through one or more radial openings in the structure-forming fiber. Numerous other aspects are provided.

Abstract: An in-line optical device adapted to be bonded in between ends of an optical fiber line is disclosed. The in-line optical device has an inner optical field interaction region, an outer support structure, and at least one radial opening. In some embodiments, a void region substantially surrounds the inner optical field interaction region. Systems including the in-line optical device and methods of making and using the in-line optical device are provided. Numerous other aspects are provided.

Abstract: Methods and apparatus for lossless LiDAR LAS file compression and decompression are provided that include predictive coding, variable-length coding, and arithmetic coding. The predictive coding uses four different predictors including three predictors for x, y, and z coordinates and a constant predictor for scalar values, associated with each LiDAR data point.