Abstract: A method of reporting an event is provided. The method includes selecting, by a device, an icon for an event. The method also includes selecting, by a device, a pin attribute for the event, wherein the pin attribute identifies the side of the road which the event is present. The method also includes presenting, by a device, the selected icon and a pin having the pin attribute at the appropriate location on a dynamic map.

Abstract: The invention relates to a method of assisting piloting an aircraft. The method is performed when the real position of a symbol for display lies outside the display limit of the screen. The symbol is representative of a parameter associated with the dynamic behavior of the aircraft (FPV, . . . ) or liable to influence said behavior (FD, . . . ). The symbol possesses two components, and the first component is to be given precedence on display over the second component. In the method, the display of the symbol depends firstly on the orthogonal projection (FPV-lock) of the real position (FPV) of the symbol onto the axis of the first component, and secondly on the position of said projection relative to the display limit of the screen. Such a display makes it possible to give reliable information to the pilot.

Abstract: In a method for identifying consumers in a pneumatic, hydraulic, or electrical network, a control unit detects connection and disconnection processes of the consumers, and the connection and disconnection processes are associated with the consumers. Comparative profiles of consumers are stored in the central control unit, each detected connection and disconnection process is compared with the stored comparative profiles, and the detected connection and disconnection process is associated with a certain consumer at least with a certain probability.

Abstract: An electricity monitoring system of monitoring electricity usage within a unit. The electricity monitoring system may include a transceiver module configured to receive an electricity usage report from a smart device associated with a unit. The electricity usage report may indicate electricity usage for the smart device. The electricity monitoring system may also include a determination module configured to generate a unit electricity usage report for the unit based on the received electricity usage report. The unit electricity usage report may indicate electricity usage for the unit. The transceiver module may be further configured to transmit the unit electricity usage report to a provider of electricity for the unit.

Abstract: A sensor arrangement comprises at least a first magnetic-field sensor (SM1) and a second magnetic-field sensor (SM2). A signal-processing unit (PROC) is set up to determine a minimum signal (MIN) and a maximum signal (MAX) of the first or second magnetic-field sensor (SM1, SM2) in the full scale range (FSR) of the sensor arrangement The first or second magnetic-field sensor (SM1, SM2) can be selected by means of a selection means (MOV) depending on the minimum and maximum signal (MIN, MAX).

Abstract: A rotary encoder includes a rotatable conductor and first and second signal contacts. The rotatable conductor includes a first contact finger that slides on a track which is at least a part of a circle having a center point as a center thereof; and second contact finger that slides on the track and is located at an angular position different from an angular position of the first contact finger. The first signal contact is disposed on the track, and is configured to output a signal according to an angular position of the rotatable conductor about the center point. The second signal contact is disposed on the first track, and is configured to output a signal according to the angular position of the rotatable conductor about the center point. The second signal contact is electrically independent of the first signal contact. This rotary encoder includes a small number of tracks, and accordingly has a small size.

Abstract: A sensor assembly includes a metal carrier plate (2) and a sensor housing (3) made of plastic, that contains at least one sensor element. The sensor housing (3) is connected to the carrier plate (2) by at least one screw (5) that extends through a through hole (6) of the carrier plate and is screwed into a screwing channel (7) defined in the plastic housing material of the sensor housing. As a result, the sensor assembly has a secure screwed connection.

Abstract: A flow meter device of a fluid includes a time difference measuring means which measures time for a received wave to reach a zero cross point after the received wave exceeds a reference voltage, after transmission of a signal, and a reference voltage setting means which changes the reference voltage from a minimum value to a maximum value, recognizes peak voltages of waves of the received wave based on a plurality of inflection points at which a time difference measured by the time difference measuring means when the reference voltage is changed from the minimum voltage to the maximum voltage, is significantly changed, and automatically sets the reference voltage to a point between peak voltages of particular two waves based on a ratio between the peak voltages, and the reference voltage is changed from a voltage which is close to the peak voltages of the two waves and the peak voltages are newly recognized, when the reference voltage is newly set.

Abstract: A sensor device for detecting at least one flow property of a fluid medium. The sensor device includes at least one sensor housing, in which at least one electronic module having at least one flow sensor for detecting the flow property is accommodated. The electronic module is at least partially accommodated in at least one electronic space. Furthermore, at least one pressure sensor and at least one humidity sensor are accommodated inside the sensor housing. The pressure sensor and also the humidity sensor are at least partially accommodated in at least one sensor space, which is designed separately from the electronic space.

Abstract: Fluid flows through a conduit. To measure flow speed the fluid is heated at a heating location in the conduit with a time-dependent heating strength. A speed of sound in fluid flowing in the conduit is measured at a plurality of sensing locations downstream from said heating location. The flow speed of the fluid is determined from a delay with which the time dependence is detected in the sound speeds measured at said sensing locations. In an embodiment a frequency of the variation of heating strength that is used to determine the flow speed is selected automatically dependent on the flow speed and/or other circumstances.

Abstract: A vacuum-cavity-insulated flow sensor and related fabrication method are described. The sensor comprises a porous silicon wall with numerous vacuum-pores which is created in a silicon substrate, a porous silicon membrane with numerous vacuum-pores which is surrounded and supported by the porous silicon wall, and a cavity with a vacuum-space which is disposed beneath the porous silicon membrane and surrounded by the porous silicon wall. The fabrication method includes porous silicon formation and silicon polishing in HF solution.

Abstract: A radar level gauge using comprising a transceiver, processing circuitry, a signal propagating device, and a wave guide arrangement connecting the transceiver with the signal propagation device. The wave guide arrangement includes a hollow wave guide, a first filling member made of a first dielectric material, which first filling member is arranged inside the hollow wave guide, and a second filling member made of a second dielectric material, which second filling member is arranged inside the hollow wave guide outside the first filling member with respect to the tank. The second filling member is fixed in the wave guide at least in a direction out from the tank, and is configured to withstand temperatures up to 250 degrees Celsius. During conditions of temperatures sufficiently high to soften the inner filling member, the outer filling member will thus serve to prevent the first filling member from being forced out of the wave guide.

Abstract: A waveguide coupling includes a planar radiator element which couples the transmission signal into a waveguide of the waveguide coupling. The waveguide widens in the direction of the planar radiator element, in such a way that the radiator element can be of a comparatively large diameter without the inner walling of the waveguide detracting significantly from the signal quality.

Abstract: An ultrasonic reactor water level measuring device and an evaluation method are provided and prevent a reduction in the measurement accuracy of a water level that is in a wide measurement range. The ultrasonic reactor water level measuring device includes an upper tube extending from a gas phase portion in a reactor, a lower tube extending from a liquid phase portion in the reactor, measurement tubes connected to each other and arranged at multiple stages between the upper tube and the lower tube, and units for generating and receiving ultrasonic waves, the units being arranged at bottom portions of the measurement tubes. The ultrasonic reactor water level measuring device measures levels of water within the measurement tubes and calculates a water level within the reactor from the sum of the measured water levels, the sum excluding an overlapped part of the measurement tubes.

Abstract: System, methods, and computer-readable media. A method includes transporting a mail piece, and during transport, determining physical dimensions of the mail piece. The method includes, during transport, determining a density profile of the mail piece using an x-ray scanner and determining a weight for the mail piece according to the physical characteristics and the density profile. The method includes selectively separating the mail piece during transport based on the determined weight.

Abstract: A portable luggage scale (20) comprising a lifting handle (22) or grip, a luggage support (24), a housing (28), a spring based weighing mechanism (26) within the housing (28), a weight indicating dial (30), the weight indicating dial (30) being adapted for movement relative to the housing (28) in response to spring reactions of the spring based weighing mechanism (26), and a measured weight indicating marker (36) for indicating a measured weight, that weight being readable off the dial (30) at the location of the marker (36). The lifting handle (22) can be telescopic, and the luggage support (24) can be a loop (42) of webbing.

Abstract: Methods and systems for creating Campbell diagram displays for illustrating vibration characteristics of a moving apparatus, such as a rotary machine, are provided. Data, representing vibration amplitudes and frequencies are recorded against rotational speeds of an apparatus. The data is used to create waveforms representing the forward and/or reverse vibration frequencies of the apparatus. The waveforms in turn are used to create spectral line envelopes to provide enhanced two dimensional images indicating the amplitudes of the vibrations of the apparatus at particular rotational speeds. The spectral line envelopes may be empty, filled with one or more colors, or other illustration features to impart solidity to the envelopes to enhance visibility.

Abstract: A measurement system for and method of measuring thicknesses of coatings as applied to objects and a coating system and method for. coating objects, in particular three-dimensional objects, with coatings, in particular thermal barrier coatings (TBCs), and a monitoring system for and method of monitoring a state of a thermal barrier coating (TBC) as applied to an object which is exposed to a high-temperature environment, and a TBC for use with the same.

Abstract: Techniques for hyperspectral imaging using a spatial light modulator having a plurality of pixels, including encoding electromagnetic radiation incident a first pixel at a first location and a second pixel at a second location into a first modulated signal having a first modulation frequency and a second modulated signal having a second modulation frequency, the first modulation frequency being different than the second modulation frequency. A sum of intensities of at least the first modulated signal and the second modulated signal is measured at a plurality of optical frequencies and a transform is applied to the sum to obtain an intensity of electromagnetic radiation incident each of the first location and the second location for each of the plurality of optical frequencies.

Abstract: An improved system and method of measuring the temperature of a workpiece in a processing chamber is disclosed. Because silicon has very low emissivity in the infrared band, a coating is disposed on at least a portion of the workpiece. This coating may be graphite or any other material that can be readily applied, and has a relatively constant emissivity over temperature in the infrared spectrum. In one embodiment, a coating of graphite is applied to a portion of the workpiece, allowing the temperature of the workpiece to be measured by observing the temperature of the coating. This technique can be used to calibrate a processing chamber, validate operating conditions within the processing chamber, or to develop a manufacturing process.

Abstract: A microbolometer includes a micro-bridge structure for uncooling infrared or terahertz detectors. The thermistor and light absorbing materials of the micro-bridge structure are the vanadium oxide-carbon nanotube composite film formed by one-dimensional carbon nanotubes and two-dimensional vanadium oxide film. The micro-bridge is a three-layer sandwich structure consisting of a layer of amorphous silicon nitride base film as the supporting and insulating layer of the micro-bridge, a layer or multi-layer of vanadium oxide-carbon nanotube composite film in the middle of the micro-bridge as the heat sensitive and light absorbing layer of the microbolometer, and a layer of amorphous silicon nitride top film as the stress control layer and passivation of the heat sensitive film. The microbolometer and method for manufacturing the same can overcome the shortcomings of the prior art, improve the performance of the device, reduce the cost of raw materials and is suitable for large-scale industrial production.

Abstract: The object detection device includes: a pyroelectric element configured to output a current signal in response to a change in an amount of infrared light; an I/V conversion circuit including an operational amplifier, a capacitive element serving as a feedback circuit, and a discharging circuit, and configured to convert the current signal to a voltage signal; an A/D conversion circuit configured to convert the voltage signal to a first digital signal; a digital filter configured to extract a detection component having a frequency included in a frequency band associated with an object from a waveform represented by the first digital signal by subjecting the first digital signal to an arithmetic processing, and create a second digital signal representing a waveform of the detection component; a judgment circuit configured to detect the target based on the second digital signal; and a control unit configured to control the discharging circuit based on a period corresponding to a predetermined frequency not great

Abstract: The present invention relates generally to integrated circuits. More particularly, the present invention provides a circuit and method for sensing a voltage and/or temperature from an integrated circuit device such as a Serializer/Deserializer (SerDes) integrated circuit device. But it will be recognized that the technique can be used for monitoring other system on chip devices, such as micro-controllers, digital signal processors, microprocessors, networking devices, application specific integrated circuits, and other integrated circuit devices that may desire on-chip temperature and/or voltage sensing capability.

Abstract: The present disclosure provides methods, devices, and computer-readable media for health monitoring of lights. One or more embodiments include receiving data, including a junction temperature of a light emitting diode (LED), an ambient temperature, and a drive current associated with the LED, receiving a pre-existing LED performance data set, and determining an end of life of the LED based on the junction temperature of the LED, the ambient temperature, the drive current associated with the LED, and the pre-existing LED performance data set.

Abstract: This document describes a method for measuring temperature. In accordance with the invention the temperature is determined from frequency variation of a local oscillator of a RFID tag (1).

Abstract: Improved, highly accurate microwire sensors (10) include a microwire assembly (14) including at least one primary, temperature-sensing microwire (16) encased within a closed-ended, stress-absorbing protective tube (12). Preferably, the sensor assembly (14) includes a plurality of microwires, e.g., a primary temperature-sensing microwire (16), a reference microwire (18), and a calibration microwire (20). The sensors (10) may be embedded within a heat-treatable or curable material (24) to monitor the temperature of the material (24) over a selected temperature range, e.g., during a pre- and/or post-curing temperature range. The tube (12) is formed of material which does not appreciably magnetically bias the microwire assembly (14), and substantially prevents forces exerted on the tube (12) from distorting the sensor assembly (14).

Abstract: An ultrasonic thermometer for measuring a temperature profile along a measurement axis of a structure, comprising a continuous measurement pathway of a structure (310) having a longitudinal measurement axis and proximal (202) and distal ends (204), and at least two backscatterers (332) formed therein transverse to the longitudinal axis and separated by a predetermined separation distance.

Abstract: In an electrical machinery and apparatus, a storage space is formed along an extension direction of a strand, and a temperature sensor is installed in the storage space of the strand, so that temperature of the strand can be immediately measured, and no pressure is applied to the temperature sensor in the process of forming a ground wall insulation thereby the temperature of the strand can be accurately measured.

Abstract: A system for sensing stress in a ferromagnetic material is provided. The system includes at least one magnetic flux device configured to induce a conditioning magnetic flux in the ferromagnetic material. The system also includes a sensor positioned proximate to the ferromagnetic material. The sensor includes a core, at least one excitation coil configured to induce a second magnetic flux in the ferromagnetic material, and at least one detector configured to detect changes in the second magnetic flux.

Abstract: Deflection of a free end of one plate-like member, that is caused by uniform stress, is transmitted to an other plate-like member by moving a free end of the other plate-like member. According to this configuration, the uniform stress applied to the one plate-like member is converted into stress induced by a point force in the other plate-like member, and then, the induced stress is concentrated on a fixed end side narrow portion in which a piezoresistor is provided. Thus, a novel structure for a piezoresistive surface stress sensor having high sensitivity to uniform stress applied to the surface of the sensor is provided.

Abstract: Apparatuses and methods, consistent with embodiments herein, are directed to an apparatus having a stretchable substrate and a plurality of nanostructures. While the plurality of nanostructures are adhered to the stretchable substrate, the stretchable substrate and the nanostructures are stretched and/or operate in a stretched mode in which the nanostructures are characterized by a resistance corresponding to a strain imparted due to the stretching. When the substrate is relaxed or the stretching otherwise lessened, the nanostructures continue to be characterized as a function of the strain and the corresponding resistance, with buckled segments of the nanostructures being adhered along a surface of the substrate.

Abstract: A grinding abnormality monitoring method and device for grinding a plurality of works of the same type are proposed which can improve the accuracy of judgment whether an abnormality is generated or not by properly setting a threshold value. According to the method or the device, by setting at least one of upper and lower limit values of a trial grinding load detected at the trial grinding of at least one of the works, an occurrence of grinding abnormality is judged when an actual grinding load detected at the actual grinding of work exceeds at least one of the upper and lower limit values thereof which varies depending on the time elapsed from the start of the actual grinding or a position of work relative to a grinding wheel.

Abstract: In one embodiment, a pressure sensor assembly includes an accelerometer configured to produce a first current upon movement of the accelerometer, a capacitor configured to receive the first current thereby charging the capacitor, a gate element operably connected to the capacitor and configured to discharge a second current from the capacitor upon the capacitor attaining a threshold voltage, a pressure sensor configured to receive the discharged current to produce a first signal corresponding to at least one pressure reading of the pressure sensor, and a transmitter operably connected to the pressure sensor and configured to transmit a second signal based upon the first signal to an external device configured to store data corresponding to the second signal.

Abstract: Apparatus that detects the pressure of water that can move through a water channel (26) towards and away from a pressure sensor (22), wherein the apparatus is constructed to avoid damage from freezing water. The water channel is constructed with a narrow channel portion (40) and a wide channel portion (42) connected in series, with the narrow channel portion lying closer to the pressure sensor. When the ambient temperature falls below the freezing temperature of water, water in the narrow channel portion freezes before water in the wide channel portion freezes, and frozen water in the narrow channel portion acts like a plug to prevent water (or ice) from moving toward the pressure sensor.

Abstract: Method and apparatus for determining geometrical dimensions of a wheel, especially a vehicle wheel, or of at least a part of the wheel, comprising the steps of pivoting at least one sensing device for scanning the wheel surface or a part of the wheel surface about a pivot axis in plane perpendicular to the wheel axis and determining the geometrical dimensions of the scanned wheel surface in dependence from the angular position of the at least one sensing device, wherein the angular position is determined from measured accelerations of the sensing device in two predetermined directions during the pivotal movement of the sensing device.

Abstract: Disclosed herein are a leak detection device and a remote monitoring system using the same. In accordance with the present invention, locations where multiple leaks have occurred can be accurately determined by connecting a plurality of leak sensing films in series using a plurality of slave controllers having connectors, detecting a leak occurring between the slave controllers, and sending the detected leak to a master controller at a remote place. Furthermore, the present invention provides a remote monitoring system capable of checking whether a leak has occurred or not at a remote place using an apparatus for controlling the leak sensing films.

Abstract: Mechanical, electronic, algorithmic, and computer network facets are combined to create a highly integrated advanced gas sensor. A sensor is integrated into switchgear housings. These sensors integrated into high voltage switchgear products, deployed by electric utility end users in replacement and expansion cycles, function to detect and mitigate atmospheric pollution caused by leaking SF6. As its associated gas insulated tank is charged with 10 to 350 lbs. of SF6, each gas sensor monitors its local cache of gas, accurately sensing and computing fractional percentage losses (emissions) and gains (maintenance replacement) in SF6 mass, storing data in onboard data logs, and communicating data when triggered by detection events or in response to remote requests over a hierarchical communications network, a process that continues without labor until a fractional leak is automatically detected and reported creating the opportunity for early leak mitigation.

Abstract: A method for monitoring the quality of an industrial working process, which includes identifying defects of the working process, comprises acquiring at least one signal having multiple frequency components from the industrial working process, decomposing the at least one signal having multiple frequency components in signals having single frequency components, calculating the information content for each signal having a single frequency component, analyzing the information content for each signal having a single frequency component, and if the value of the information content of the signal at the lowest single frequency component does not represent a main percentage of the information content of the whole acquired signal, the acquired signal having multiple frequency components is evaluated as indicative of a working process with defects and a defect analysis step is performed on the signal having multiple frequency components.

Abstract: A calibration device for a radiometer includes an integrating cavity and a honeycomb blackbody mounted to the integrating cavity. A plurality of emitters are mounted to the exterior rim of the integrating cavity for transmitting narrow band wavelengths of light into and out of the integrating cavity. A controller, selectively, activates one or more emitters to radiate a single narrow band wavelength of light during an ON period and turn OFF during another period. A plurality of reference detectors are also mounted to the exterior rim of the integrating cavity for measuring the intensity of each narrow band radiation outputted from the integrating cavity. The reference detectors are effective in determining changes in intensity output by each of the narrow band emitters from the integrating cavity. The measured changes in intensity outputted by the emitters are used to calibrate the radiometer with the changes traced back to a NIST standard.

Abstract: An OTDR user interface including a setup menu that includes a plurality of user settings capable of displaying information corresponding to a test, wherein each of the plurality of user settings is capable of displaying information corresponding to a different aspect of the test, and wherein one of the plurality of user settings is a dynamic range setting capable of displaying a dynamic range of the test.

Abstract: Methods and systems are provided for enabling engine diagnostics, including visual inspections of an engine cylinder, using existing hardware from a laser ignition system. Light pulses from a laser ignition device are received at a photodetector during non-combusting conditions and used to generate images of an inside of the cylinder that can be assessed by a service technician. An electric motor of the vehicle system can be used during a service mode of the vehicle to rotate the engine to, and hold the engine at, specified engine positions that enable the technician to perform selected diagnostic tests.

Abstract: Methods and systems for heating an oxygen sensor. One system includes an oxygen sensor and controller. The oxygen sensor includes a heater and an electro-chemical measurement cell and a heater. The controller is coupled to the oxygen sensor and is configured to, for each of a plurality of stages of a regeneration process, determine a predetermined temperature for heating the oxygen sensor to, determine a predetermined internal resistance value of an electro-chemical measurement cell of the oxygen sensor associated with the predetermined temperature, apply a pulse-width-modulated signal to the heater, and monitor an internal resistance of the measurement cell while applying the pulse-width-modulated signal to the heater to determine when the internal resistance of the measurement cell reaches the predetermined internal resistance.

Abstract: In a conventional chassis dynamometer, when a roller opening formed in a pit cover is closed by an open/close plate, the open/close plate is projected from an upper surface of the pit cover so that irregularities are generated on the upper surface of the pit cover. A chassis dynamometer 1 includes rollers 2, 3 on which wheels of a test vehicle are rested through roller openings 6, 7 formed in a pit cover 5, and an opening open/close mechanism 15 that opens and closes the roller openings 6, 7. The rollers 2, 3 are ascendably and descendably operated by a roller ascent/descent operation mechanism 8. The rollers 2, 3 are operated to descend, and the roller openings 6, 7 are closed by open/close plates 16.

Abstract: A device for simulating the effects of a crash on a test object is provided. The device includes a sled adapted to be accelerated in the longitudinal direction. The sled comprises a lower part and an upper part supported thereon used as a carrier for the test object. The lower part and the upper part have actuators provided between them, whereby pitching and yawing movements of the upper part can be generated. The upper part is, on an impact-side front end of the sled, propped against the lower part by means of a coupling rod which is rotatably coupled on both sides thereof, at least five actuators provided between the lower part and the upper part, the upper part being supported on the lower part via the actuators and the coupling rod such that a rolling movement of the upper part can additionally be generated by means of the actuators.

Abstract: A self-contained mobile sampling and processing facility for use at a mine having at least one blast-hole that forms a blast-hole cone wherein the sampling and processing facility includes at least one primary robotic arm that carries at least one sampling tool, and the primary robotic arm and sampling tool is controlled by robotic arm and sampling tool movement controller means, and the primary robotic arm is capable of self-determining the direction, distance and shape of a nearby blast-hole cone, then subsequently positioning itself so that the sampling tool is able to engage with the blast-hole cone and retrieve a sample from it without significant mixing or stirring the cone, or a localized region of the cone, and then the sample is deposited into the processing facility.

Abstract: A collection unit (80)includes: a collection carrier cartridge (82) formed, at its center, with a through hole (82b3) into which a nozzle for supplying hot water or ATP reagent is inserted including a carrier filling dish (82b), on an outer circumference of the through hole (82b3), to be filled with a collection carrier (90) for collecting floating bacteria in the air, and an upper lid (82a) on which the carrier filling dish (82b) is placed, formed with a protrusion to be inserted through the through hole (82b3); an impactor nozzle head (86) covering a surface of the collection carrier (90) and has a plurality of nozzle holes (87) facing the collection carrier (90) surface; and a fan (84) introducing air to the collection carrier surface through the nozzle holes (87). A velocity of the air passing through the nozzle holes (87) is 40 m/s to 50 m/s.

Abstract: A method for removing supernatant from a sample tube. The method includes providing a sample tube having a pellet at a bottom of the sample tube and a supernatant liquid above the pellet, visually inspecting the sample tube to determine one or more geometric properties of the pellet, and determining an expected height of a top surface of the pellet based on the one or more geometric properties determined in the visual inspection step. The method also includes inserting an aspirator into the supernatant liquid, moving the aspirator downwards towards the expected height of the top surface of the pellet, and aspirating the supernatant liquid through the aspirator.

Abstract: A micro flow device (11, 71) for separating or isolating cells from a bodily fluid or other liquid sample uses a flow path where straight-line flow is interrupted by a pattern of transverse posts (23, 81). The posts are spaced across the width of an expanded collection chamber region (17, 75) in the flow path, extending between the upper and lower surfaces thereof; they have rectilinear surfaces, being curved in cross-sections, e.g. circular or tear-drop shaped, and are randomly arranged so as to disrupt streamlined flow. The device is oriented so that its lower surface is aligned at about 45° to the horizontal. Sequestering agents, such as Abs, which are attached to surfaces of the collection region via a hydrophilic coating, preferably a permeable hydrogel containing isocyanate moieties, are highly effective in capturing cells or other targeted biomolecules while the remainder of the liquid sample exits horizontally.

Abstract: An apparatus and method that may be used for collecting target cells or tissue and preparing a cell block are disclosed.

Abstract: An automated headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry for the determination of four N-nitrosamines in groundwater samples is developed. Response surface methodology technique was employed to investigate the optimized extraction conditions of headspace solid-phase microextraction using CombiPAL autosampler. The method was applied to determine the N-nitrosamine concentrations in groundwater samples.