Abstract: A maximum number of charges on aerosol particles which are measurement targets is decided as a natural number x equal to or larger than 2. First and second electrical mobility groups are derived based on x. The first group includes electrical mobility Zc(U) and electrical mobilities having voltage values equal to a voltage U multiplied by values from 2 to x respectively, and the second group includes electrical mobilities having respective voltage values equal to voltage U multiplied by irreducible fractions which are coprime to each other among values with regularity. A ratio of flow rate with which range corresponding to the electrical mobilities included in the first group do not interfere with one another and the range corresponding to the electrical mobilities included in the first group and range corresponding to the electrical mobilities included in the mobility group do not interfere with one another is calculated.

Abstract: A method and a device for determining the flow rate of magnetic or ferromagnetic particles in a suspension that flows through control chambers are provided. The magnetic flux F1 is measured as a function of time t using a measuring coil that surrounds a first control chamber, the magnetic flux representing a measurement, at a particular time, of the quantity of magnetic particles contained in the suspension. In a second control chamber, at a predetermined distance d from the first control chamber, the magnetic flux F2 is measured as a function of time t using a second measuring coil that surrounds the second control chamber and the measurements F1 (t) and F2 (t) are compared to produce a temporal distance ?t which is used together with the predetermined distance d to calculate the flow rate. The method and device can be used, for example, in an ore mining installation.

Abstract: A flow sensor assembly, snore detection assembly, and methods for fabricating the same. The flow sensor assembly includes a flow conduit for fluid flow, a flow disrupter for imparting a disturbance to the fluid flow, a first sensor responsive to the disturbance of the fluid flow and configured to generate signals responsive to the disturbance of the fluid flow, and a processor for determining a flow rate for the fluid flow through the flow conduit based on a first algorithm determining an amplitude of the fluid flow in a first flow regime and a second algorithm determining a frequency of the fluid flow in a second flow regime.

Abstract: Method and system for calibrating a mass flow sensor. The mass flow sensor includes an impact sensor that receives an impact force due to collisions with a plurality of solid particles to generate an output signal. A model relates a mass flow input to the output signal. At least one measurable parameter is varied over a plurality of samples by varying a physical component of the mass flow sensor, and a generated output signal is received. The model can be calibrated based on the received output signal for each of the plurality of samples. A mass-flow input can also be estimated while simultaneously updating the model.

Abstract: A system and method for measuring an EGR flow rate for an engine having an EGR valve with a selectable EGR valve position and a venturi sensor situated to take a differential pressure measurement relative to recirculated exhaust gas includes determining an EGR valve effective area based on the EGR valve position, determining a weighting factor based on the effective area, calculating a first EGR flow estimate based on the effective area, and calculating a second EGR flow estimate based on the differential pressure measurement of the venturi sensor. A final EGR flow rate is determined based on the weighting factor, the first EGR flow estimate, and the second EGR flow estimate.

Abstract: A vibration-type measuring device includes an exciter arrangement which exerts a time-dependent force with at least one sinusoidal component at an adjustable excitation frequency on a measuring tube, through which a medium can flow, and causes the measuring tube to oscillate. The measuring device includes first and second sensors which are fitted to the measuring tube at different locations. The first and second sensors output first and second measurement signals, respectively. The measuring device includes an evaluation unit which determines a first phase shift between the first and second measurement signals and uses the determined phase shift to determine a measurement variable of the medium. The measuring device includes a phase comparator, which determines a second phase shift between the force and the average value of the first and second measurement signals, and a frequency generator which sets the excitation frequency on the basis of the second phase shift.

Abstract: A thermal mass flow meter is disclosed wherein a sensor board with at least one heating element and at least two temperature sensors locates inside a housing where the gas or fluid is flowing. The heating element is turned on and off and a microprocessor is programmed to calculate a flow rate based on a logarithmic function of temperature differences between a pair of sensor before the heating cycle and after the heating cycle.

Abstract: A method of deducing time based metrics using flow rate is disclosed. The method uses a thermal mass flow meter wherein the meter comprises a pipe housing and a sensor board with at least one heating element and at least two temperature sensors is located inside the pipe and where a microprocessor is programmed to calculate a flow rate based on a logarithmic function of difference between base line temperature difference between temperature sensors before heating element is turned on and a second temperature difference between the temperature sensors after heating element is turned on. Duration of gas supply is provided by using the measured flow rate and information of the gas supply.

Abstract: A valve system for a mass flow controller that controls a flow rate of a fluid is disclosed. The valve system includes a valve movable between an open position and a closed position to adjust the flow rate of the fluid to a desired set point, and a valve controller. The valve controller sends a valve current through the valve, so as to adjust the flow rate of the fluid until an actual measured flow rate of the fluid substantially equals the desired set point. The valve controller monitors the valve current and the flow rate when the valve is moving to the closed position, determines a value of the valve current when the fluid has near-zero flow rate, and updates the valve cracking current for a next run, by setting the updated valve cracking current to the value of the valve current at the near-zero flow rate.

Abstract: An object is to prevent a mistaken shutoff caused by the mistaken registration of an appliance of which an amount of gas used changes. An individual flow registration maintenance unit maintains a registered flow rate deleted due to an increase/decrease in flow rate, again, performs determination on the flow rate maintained when a new flow rate is registered or a flow rate added with the maintained flow rate, and in the case where it is regarded to be the same, re-register the maintained flow rate.

Abstract: Flowmeters are described in which a sensor signal received from a sensor that is attached to vibratable flowtube, so as to determine properties of a fluid within the flowtube, contains a drive signal component and a Coriolis mode component. The flowmeters are operable to determine drive parameters of the drive signal component, as well as Coriolis parameters of the Coriolis mode component. By analyzing the sensor signal based on the drive signal parameters, and not on the Coriolis signal parameters, the flowmeters are able to provide stable and accurate determinations of the properties of the fluid.

Abstract: One aspect provides a fluid flow measurement instrument, comprising: a sensor producing a signal representative of reflections of an emitted signal; and a meter being coupled to the sensor and configured to: produce two or more sub-measurements from said signal representative of reflections of an emitted signal; and compute a fluid flow velocity estimate using the two or more sub-measurement signals. Other aspects are described and claimed.

Abstract: An ultrasonic phase-shift detection device includes a clock generator, a divider, a first counter, a comparator, a phase detector and a second counter. The divider is provided for dividing the clock signal to generate ultrasonic signals. The comparator is provided for comparing the counting value of the first counter and a predetermined number. The phase detector is provided for comparing the phase shift between different ultrasonic signals. The second counter is provided for counting to generate the digital result signal.

Abstract: A Coriolis mass flowmeter includes a vibrator configured to vibrate a measurement conduct line, an upstream sensor and a downstream sensor, which are placed at a certain distance in the measurement conduct line and are configured to detect the vibration of the measurement conduct line, a first effective value reception section configured to receive an effective value of the first signal, a second effective value reception section configured to receive an effective value of the second signal, a ratio computation section configured to receive the effective value of the first signal and the effective value of the second signal and to compute the ratio of both values, and an anomaly diagnosis section configured to make a comparison between the computed ratio and a certain value and to generate an alarm.

Abstract: A measuring system for precise measuring a density of a medium flowing in a pipe line. The measuring system comprises a temperature sensor and a pressure sensor. Both sensors communicate with a measuring electronics of the system. The measuring electronics are operable to provide, based on temperature measurement and pressure measurement, a provisional density measured value, especially according to one of the industrial standards AGAR, AGN NX-19, SGERG-88 IAWPS-IF97, ISO 12213:2006. Further, the measuring electronics provides, based on the provisional density measured value and a density correction value, which is dependant on a flow velocity of the medium, and temperature measurement, a density measured value, which differs from the provisional density measured value, and which represents the density to be measured more accurately.

Abstract: A mobile flow rate measuring system and method, which can recognize a flow rate at a site, and acquire and utilize data on water level, flow velocity, and flow rate of a plurality of agricultural waterways, by acquiring water level information and site features stored in a remote server from a tag installed at the site by a mobile apparatus and comparing images continuously acquired from the agricultural waterways through an image photographing camera to calculate the surface velocity of the waterway.

Abstract: A restroom monitoring system for monitoring attributes of fixtures within a restroom using sensors. Additional attributes are determined from the monitored attributes. Consumable usage levels are estimated based on predetermined consumption levels associated with usage states of the fixtures. The restroom monitoring system provides an indication of the need for replenishment of consumables based on the monitored attributes of the fixtures. In addition, restroom monitoring system may provide additional information regarding the restroom attributes to a service provider, a manager or a user.

Abstract: A flow sensor assembly is provided and includes a flow conduit configured to impart a disturbance to a flow, multiple sensors disposed at respective sensing locations along the flow conduit. Each sensor is responsive to the disturbance of the flow and generates a corresponding response signal. The flow sensor assembly further includes a processor operably connected to each sensor, the processor being configured to compute a cross-correlation function between the response signals generated by said sensors, and determine a flow rate and a direction for the flow through the conduit based on the computed cross-correlation function. Additional flow sensor assembly arrangements are also disclosed.

Abstract: A flow device is provided. The flow device includes at least one conduit (20) and a pick-off (30) providing a pick-off signal (35) for measuring motion of the at least one conduit (20). The flow device also includes a drive (40) that receives a first signal (55) for vibrating the at least one conduit (20) at a resonance frequency and that receives a second signal (56) for vibrating the at least one conduit at a frequency that is different than the resonance frequency. One or more electronics (50) is provided. The one or more electronics (50) generates the first and second signals (55, 56), receives the pick-off signal (35) from the pick-off (30), and measures changes in a time shift between the second signal (56) frequency applied by the drive (40) and the second signal (56) frequency detected by the pick-off (30).

Abstract: A system for controlling a motorized track light system constrained to travel along a track has a control unit coupled to a motor that causes the track light system to move along the track, a plurality of stop sensors strategically disposed along the track, a sensor activation device located on the track light system, the sensor activation device positioned to interface with the stop sensors, and a light sensor for detecting ambient light of a preset level. The system detects a preset level of ambient light, initiating power to the motor of the track light system, moving the lights along the track until the activation device interfaces with a first of the plurality of stop sensors, stopping movement of the track light system along the track for a preset period of time, and at the end of the preset time period, the electrical power is restored to the motor moving the track light assembly along the track to the next of the plurality of stop sensors.

Abstract: An apparatus and method for estimating a parameter of a fluid flowing in a tubular is disclosed. A source of a primary magnetic field is coupled to the tubular and is configured to induce the primary magnetic field in the fluid to align nuclei of the fluid in the tubular along the primary magnetic field. A transmitter transmits an excitation signal into the fluid. A receiver detects a signal from the aligned nuclei responsive to the excitation signal. A processor estimates the parameter of the fluid from the detected signal. The source of the primary magnetic field is removable from the tubular. A coil may induce a secondary magnetic field to either enhance the strength of the primary magnetic field in the tubular or substantially cancel the primary magnetic field in the tubular, for example, to reduce particle build-up in the tubular.

Abstract: A method of machine condition monitoring, wherein at least one measured and/or calculated machine parameter is monitored during the operation of a machine, and wherein a change in the machine condition, particularly a critical operating state of the machine, is deduced when at least one monitored machine parameter reaches a limit value, and wherein at least one monitored machine parameter is monitored depending on at least one other machine parameter in defined operating point ranges of the machine, wherein a change in machine condition is deduced when at least one monitored machine parameter within a defined operating point range reaches at least one limit value individual to the operating point range.

Abstract: One aspect of the invention provides a flow sensing apparatus including: a fluid channel that allows a fluid to flow in a first direction; a first temperature sensor arranged at a first position along the fluid channel; a second temperature sensor arranged at a second position along the fluid channel and separated from the first sensor by a predetermined distance along the fluid channel; a heating element arranged between the first and second thermoelectric sensors, the heating element being substantially equally spaced from the first and second thermoelectric sensors; a heating element temperature sensor for sensing a temperature of the heating element; and a control device configured to maintain the heating element at a substantially uniform temperature.

Abstract: An airflow-sensing computer cursor generator includes a microprocessor and plural air flow rate sensors. The plural air flow rate sensors are used for sensing airflow rates resulted from a moving action of an inductor in plural directions, thereby generating respective air flow rate signals corresponding to the plural directions. The microprocessor is used for judging a moving direction and a displacement value of the inductor according to the air flow rate signals, thereby generating a computer cursor signal.

Abstract: A monitoring system including two laser anemometers and a selection logic device able to select, on the one hand, a value of the IAS air speed to be displayed on first display means and, on the other hand, another value of the IAS air speed to be displayed on second display means.

Abstract: An apparatus comprises a pipe section for process flow, a coil for generating a magnetic field across the pipe section, a current source for energizing the coil to generate the magnetic field, and an electrode for sensing an electromotive force induced across the process flow by the magnetic field. The current source energizes the coil at a plurality of different pulse frequencies. A processor calculates a function of the electromotive force at the plurality of different pulse frequencies, and generates a flow output based on the function.

Abstract: An apparatus and method for identifying one or more fluid products flowing within a pipe are provided having a flow meter mounted on the pipe and a processing unit. The flow meter has a plurality of sensors operable to detect vortical disturbances flowing with the fluid products and acoustic waves propagating through the fluid. The sensors produce signals indicative of the vortical disturbances and acoustic waves. The processing unit is operable to determine the speed of sound and volumetric flow rate of the one or more fluid products using the signals from the flow meter. The processing unit includes a database having speed of sound data for a predetermined group of products. The processing unit is operable to identify the type of each product flowing within the pipe given a temperature and pressure value of the products within the pipe.

Abstract: The invention concerns a process for detecting scale deposit in the liquid supply means of a water pump driven machine comprising at least a water tank, a pump and a heating means, where water is pumped from the water tank and fed to the heating means, and where the pump is energized by a controller by providing the pump with an energizing signal to provide an intended water flow rate F, wherein the actual water flow rate f is measured and the discrepancy ? between the actual water flow rate f and the intended water flow rate F is directly and/or indirectly compared to an operating instruction related to scale deposit.

Abstract: Methods of and devices for testing medical pumps via tracking induced single or multiple bubble trajectories within a fluid flow conduit (60) and methods of synchronized (600) corrections (604) of flow data estimates.

Abstract: Methods of and devices for testing medical pumps via tracking induced single or multiple bubble trajectories within a fluid flow conduit (60) and methods of synchronized (600) corrections (604) of flow data estimates.

Abstract: Diesel fuel consumption is calculated in real-time in an vehicle diagnostic monitor using standard OBDII reported parameters and publicly available engine characteristics. Also, fuel consumption in vehicles that maintain a constant air-fuel ratio is calculated by analyzing the subject engine as an air pump and reading publicly available OBDII diagnostic data to estimate the instantaneous airflow through the engine without the need of MAF sensor data.

Abstract: A method is provided for precisely predicting the temporal variation of a membranous filtration resistance, a transmembrane pressure, a membranous filtration flowrate, or a membranous filtration flowrate as occurs in filtrating a liquid with a membrane, in a membranous filtration method wherein the liquid is filtrated by the separation membrane with the transmembrane pressure as a driving force. The method includes calculating: a constituent component quantity value of the liquid that attaches on a surface of the separation membrane at a time t+?t; a constituent component quantity value of the liquid that exists in pores of the separation membrane; a consolidation degree of a constituent component of the liquid that attaches on the separation membrane surface; a membranous filtration resistance value; a transmembrane pressure value; and a membranous filtration flowrate value.

Abstract: A system model of a real-world system includes a multi-level hierarchy of Capabilities, where each Capability includes a Verb specifying an action and an Object acted on by the Verb. The system model also contains one or more multi-level Performer hierarchies, where each Performer hierarchy includes a plurality of Performers each having an associated lifecycle and at least one associated Capability provided or required by the Performer. In addition, a multi-level Location hierarchy associates one of a plurality of Locations with each Performer. A plurality of Capability Instances define requirement and provision of Capabilities by Performers in the one or more multi-level Performer hierarchies. In response to a query specifying a Location and a time, a view of the system model for the specified Location and time is output.

Abstract: A system and method for improving energy usage and conservation of at least one air-management unit in a data center where a multiplicity of rack mounted power distribution units are used for power distribution to a multiplicity of electronic devices mounted on a plurality of racks in at least one computer room of the data center. A group of power load, temperature, humidity and differential pressure sensors are provided throughout the racks, and coupled to a computer through a network interface for automatically calculating multiple air-management effectiveness and energy efficiency indices (e.g., rack cooling index RCI, rack humidity index RHI, rack airflow index RAI, rack differential pressure index RPI and return temperature index RTI) based on the data from the sensors, such that the operation of the air-management unit can be adjusted accordingly to achieve an optimal efficiency of safe energy usage and conservation.

Abstract: A technique for utilizing tube waves to measure sound speed of fluids and other properties in the frequency range of about 5 to 100 kHz. A drill string is equipped with a sensor tube having a cavity filled with a downhole fluid such as borehole mud or formation fluid. An acoustic transmitter and an array of acoustic receivers are mounted on the tube in direct contact with the fluid. Processing circuitry calculates a property, e.g., sound speed, of the fluid based on time-of-flight of an acoustic signal generated by the transmitter and received by the array of receivers. Alternatively change in signal phase as a function of frequency may be employed by the processing circuitry. The technique is particularly suited to measuring the sound speed of borehole mud in situ.

Abstract: The invention relates to a method of classifying and flow measuring the refringence of at least two populations of particles present in a fluid. The method uses a light source that has small coherence time, with a coherence length Lc<100 ?m, that is used under extinction conditions at a center wavelength selected as a function of a range of volumes and of a range of refractive indices expected for the particles under consideration. The method uses a device that, together with the light source, forms a converging illuminating beam of aperture angle that is selected as a function of the range of volumes and the range of refractive indices expected for the particles under consideration at the selected center wavelength.

Abstract: Systems and methods for analysis of data associated with fluid flow through a conduit and potential control of the fluid flow. In one embodiment, a method includes a data processing unit obtaining from a sensor a signal representing a series of measurements of a physical parameter associated with fluid flow through the conduit. The data processing unit performs singular spectral analysis of this signal and thereby identifies recurring, possibly non-sinusoidal patterns in the signal. The data processing unit may construct a second signal from some or all of the recurring patterns identified in the first signal. Alternatively, the data processing unit may identify recurring patterns in the signal which are indicative of corresponding conditions associated with the fluid flow through the conduit. The data processing unit may then initiate control functions responsive to the recurring patterns and associated conditions.

Abstract: The present invention is a hand held gauge for use with refrigeration systems. The gauge includes a service port connector, a display screen, and user interfacing buttons. The gauge also includes electronic storage of the pressure-to-saturation temperature data for different refrigerants. The gauge allows for the measuring of temperature and pressure of refrigeration systems. After a user inputs a refrigerant type, the gauge uses the pressure and the saturation data to determine the saturation temperature. The saturation temperature is compared to the measured temperature to get the superheat or subcooling. These results may all be displayed on the display screen.

Abstract: A device for measuring the flow rate of a fluid in a conduit, including a bladed impeller mounted in the conduit so as to be driven in rotation by the flow of the fluid, and to which at least one magnet is fixed, and at least one magnetic field sensor arranged in a fixed position near the conduit and capable of causing the generation of a signal (pulse) each time the magnet of the impeller, passes thereby. The arrangement is such that the number of signals (pulses) generated by the sensor in a period of time is representative, according to a predetermined relationship, of the flow rate of the fluid in the associated conduit.

Abstract: A digital liquid flow rate meter that comprises a body adapted to delimit a conduit for conveying liquid with two connectors which provided respectively with male threading and with female threading. In the conduit a turbine is inserted provided with a magneto that transmits impulses to a microprocessor comprised within the body and provided with an electronic card complete with display for direct reading of the flow rate of liquid conveyed. The turbine is associated with a shaft that transmits selectively at the ends, according to the direction of travel of the liquid, an axial thrust to corresponding supports that are inserted in the conduit. The shaft is provided with anti-wear elements that are adapted to ensure operation in the absence of wear in both directions of travel of the liquid.

Abstract: A method for controlling the influx of fluids into a multizone well in which each inflow zone is provided with an inflow control device, comprises: assessing the flux of oil, gas, water and other effluents from the well; monitoring production variables, including ICD position and/or fluid pressure in each inflow zone upstream of each ICD and/or downstream of each ICD; sequentially adjusting the position of each of the ICDs and assessing the flux of crude oil, natural gas and/or other well effluents; monitoring production variables; deriving a zonal production estimation model for each inflow zone of the well; and adjusting each ICD to control the influx of crude oil, natural gas and/or other effluents into each inflow zone on the basis of data derived from the zonal production estimation model for each inflow zone of the well.

Abstract: A flow meter for measuring flow of a process fluid includes a sensor configured to provide a sensor output signal. The sensor output signal is related to flow of the process fluid. Circuitry in the flow meter is configured to determine a statistical parameter related to sensor output signal. Diagnostic circuitry provides a diagnostic output based upon the determined statistical parameter and the sensor output signal.

Abstract: A vibratory flow meter (100) for correcting for entrained gas in a flow material is provided. The vibratory flow meter (100) comprises a flow meter assembly (10) configured to generate a vibrational response for the flow material, a bubble size sensor (50) configured to generate a bubble measurement signal for the flow material, and meter electronics (20) coupled to the flow meter assembly (10) and to the bubble size sensor (50). The meter electronics (20) is configured to receive the vibrational response and the bubble measurement signal, determine a bubble size of bubbles in the flow material using at least the bubble measurement signal, determine one or more flow characteristics of the flow material using at least the vibrational response and the bubble size.

Abstract: A method and system are provided for airflow management in a data center. The data center includes network elements, sensors, and heating, cooling and ventilation (HVAC) equipment. The sensors measure climate conditions in the data center and provide an airflow management system with measurements that are utilized to determine which areas in the data center violate data center temperature thresholds and require more air capacity. The airflow management system increases the airflow to areas that contribute to the violation by controlling HVAC equipment to increase air movement or by selecting other areas in the data center or external to the data center that have excess capacity and routing the excess capacity to the areas that contribute to the violation.

Abstract: An apparatus for generating a measure of fluid. The apparatus comprises a flow meter and a pulser having an identifier and a memory. The pulser is associated with the flow meter for generating pulser data indicative of a volume of fluid delivered through the flow meter. The pulser may alter the pulser data using correction data stored in its memory to generate altered pulser data. The pulser may store at least one of the pulser data and the altered pulser data in the memory. The apparatus further comprises a switch operatively connected to the pulser's memory. The switch is operative to vary the memory of the pulser between a write-protected and a write-enabled mode. Also, the apparatus comprises a controller in communication with the pulser and a serial communication circuit which enables communication between the pulser and the controller. Communication between the controller and the pulser includes the identifier.

Abstract: A method, and apparatus for software and resource management with a model-based architecture.

Abstract: Methods and apparatus enable sensing flow of a fluid inside a conduit with an array of pressure or strain sensors. Inputs for a curve fit routine include power correlation values at one of multiple trial velocities or speeds of sound and several steps on either side utilizing data obtained from the sensors. The velocity at which a curve fit routine returns a max curvature result corresponds to an estimate value that facilitates identification of a speed of sound in the fluid and/or a velocity of the flow. Furthermore, a directional quality compensation factor may apply to outputs from the curve fit routine to additionally aid in determining the velocity of the flow.

Abstract: Provided is an easy to use valve controller designed to obtain optimum operation performance. The valve controller is designed to control the valve opening of an expansion valve by calculating the valve opening such that a detected temperature coincides with a target temperature. The valve controller includes an automatic for calculating a deviation between the detected temperature and the target temperature and for calculating a changing amount of the valve opening by substituting at least the deviation and a set control parameter into an arithmetic expression to automatically set the control parameter. The valve controller further includes and control level adjuster for adjusting a magnitude of the valve opening calculated with the control parameter set by the automatic tuning means in stages in accordance with a set control level.

Abstract: A method of calculating a control parameter for a component in an HVAC system includes receiving a plurality of input signals, and calculating a value of the control parameter using a control parameter equation having a plurality of predetermined coefficients and a plurality of variables, each variable corresponding to one of the input signals. This equation is stored in and subsequently fetched from memory associated with a component of the HVAC system, such as a blower motor controller or a system controller. In some embodiments, the equation is stored in a device for interfacing a system controller with a blower motor assembly.

Abstract: An intelligent gas flow sensor probe which outputs a state signal indicating whether there is forced gas flow present within a conduit or whether there is no gas flow. The intelligent gas flow sensor probe includes a heated thermistor and a reference thermistor functionally coupled to a microcontroller. The heated thermistor is continuously heated at a constant rate to a temperature above an ambient temperature within the conduit and outputs a signal responsive to a change in temperature induced by gas flow incident thereupon. Gas flow within the conduit causes heat to be transferred from the heated thermistor to the gas flowing over and/or around the heated thermistor. The reference thermistor is thermally insulated from the heated thermistor and outputs a reference signal responsive to an ambient temperature of the gas within the conduit.