Abstract: Systems and methods for establishing and/or maintaining the accuracy of a multivariate calibration model designed for quantitative optical spectroscopic measurement of attributes or analytes in bodily tissues, bodily fluids or other biological samples, which are particularly useful when the spectral absorbance of the attribute or analyte is small relative to the background. The present invention provides an optically similar reference sample to reduce the effect of instrument or environment variation on the measurement capability of the model. The optically similar reference can be a gel composition having scattering particles suspended therein. The reference gel can be directly applied to a spectroscopic instrument sampler, or can be in a container specifically designed for optimal coupling to a spectroscopic instrument.

Abstract: A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can comprise single wavelength excitation light, scanning of excitation light (illuminating the tissue at a plurality of wavelengths), detection at a single wavelength, scanning of detection wavelengths (detecting emitted light at a plurality of wavelengths), and combinations thereof. The invention also can comprise correction techniques that reduce determination errors due to detection of light other than that from fluorescence of a chemical in the tissue.

Abstract: A method and apparatus providing for efficient operation of gas engines in non-ideal temperature conditions. An apparatus is provided in fluid communication with a source of gas, and with the gas input of a gas engine. The apparatus accepts gas from the source, and allows the gas to reach the gas engine via one or two reservoirs. Pressure regulators can be mounted with the input ports, output ports, or combinations thereof, of the reservoirs. An exhaust channel accepts exhaust from the gas engine and passes it along a path that is in thermal communication with the reservoirs, such that the exhaust encourages a more uniform and higher operating temperature of the gas supplied to the pressure regulators and to the gas engine.

Abstract: Apparatus and methods for spectroscopic analysis of human tissue to classify an individual as diabetic or non-diabetic, or to determine the probability, progression or level of diabetes in an individual. Tissue optical information of an individual, including at least a measurement of at least one wavelength or group of wavelengths indicative of glycosylated collagen content in tissue, is analyzed using multivariate techniques. The multivariate techniques include an algorithm developed from optical information from individuals having a known disease state. At least one factor in the algorithm is dependent on or a function of the measurement of the at least one wavelength or group of wavelengths indicative of glycosylated collagen content in tissue from the optical information of individuals forming the database.

Abstract: The present invention relates generally to a non-invasive method and apparatus for measuring a fluid analyte, particularly relating to glucose or alcohol contained in blood or tissue, utilizing spectroscopic methods. More particularly, the method and apparatus incorporate means for detecting and quantifying changes in the concentration of specific analytes in tissue fluid. Also, the method and apparatus can be used to predict future levels of analyte concentration either in the tissue fluid or in blood in an adjacent vascular system.

Abstract: The present invention provides an improved interferometer design. Embodiments of the present invention provide a beam splitter, mounted with first and second reflective elements. An OPD element mounts relative to the other elements such that an optical path in the interferometer passes through the OPD element. The OPD element can be, for example, a plate comprising a refractive material mounted such that the thickness of the refractive material encountered by the optical path through the OPD element is variable. Various arrangements of components are described, and methods of constructing and methods of aligning such interferometers are also described.

Abstract: The present invention provides a method of human-computer interfacing that provides haptic feedback to control interface interactions such as scrolling or zooming within an application. Haptic feedback in the present method allows the user more intuitive control of the interface interactions, and allows the user's visual focus to remain on the application. The method comprises providing a control domain within which the user can control interactions. For example, a haptic boundary can be provided corresponding to scrollable or scalable portions of the application domain. The user can position a cursor near such a boundary, feeling its presence haptically (reducing the requirement for visual attention for control of scrolling of the display). The user can then apply force relative to the boundary, causing the interface to scroll the domain. The rate of scrolling can be related to the magnitude of applied force, providing the user with additional intuitive, non-visual control of scrolling.

Abstract: The present invention provides means for correcting interferometer alignment errors through the use of corrective elements. The corrective elements allow reduced accuracy in the assembly process. Residual alignment errors caused by imprecise mounting of permanently mounted components can be corrected using relatively low precision positioning of corrector components. The technique can be particularly applicable to the mass production of interferometers, for which achieving and maintaining the required assembly tolerances might otherwise be prohibitively expensive. Interferometers according to the present invention can be used, for example, in optical spectroscopy and in interferometers.

Abstract: Methods and apparatuses of determining the pH of a sample. A method can comprise determining an infrared spectrum of the sample, and determining the hemoglobin concentration of the sample. The hemoglobin concentration and the infrared spectrum can then be used to determine the pH of the sample. In some embodiments, the hemoglobin concentration can be used to select an model relating infrared spectra to pH that is applicable at the determined hemoglobin concentration. In other embodiments, a model relating hemoglobin concentration and infrared spectra to pH can be used. An apparatus according to the present invention can comprise an illumination system, adapted to supply radiation to a sample; a collection system, adapted to collect radiation expressed from the sample responsive to the incident radiation; and an analysis system, adapted to relate information about the incident radiation, the expressed radiation, and the hemoglobin concentration of the sample to pH.

Abstract: The invention relates to a device for the decontamination of water, particularly of heavy metals and/or arsenic and/or their compounds, by means of electrolysis, wherein the water to be purified is fed through a receptacle and passes by electrodes of different polarities. According to the invention, a combination of electrodes made from iron, aluminium, and graphite, or from aluminium and graphite, is used. Facing the direction of the receptacle bottom, the undersides of the electrodes are contained in groove-like, electrically insulated recesses that are spaced apart and separated from one another on their opposite side by single electrically insulating spacers, wherein the spacers are attached to the electrodes, and the electrodes, which can be unfolded, are arranged in the groove-like recesses (FIG. 5).

Abstract: A sensor provides a persistent indication that it has been exposed to temperatures below a certain critical temperature for a predetermined time period. An element of the sensor made from shape memory alloy changes shape when exposed, even temporarily, to temperatures below the Austenitic start temperature As and well into Martensite finish temperature Mf off the shape memory alloy. The shape change of the SMA element causes the sensor to change between two readily distinguishable states. The sensor includes a one-way stop element that creates a persistent indication of the temperature history, allowing the sensor to be manufactured and stored at temperatures above the Austenitic temperature without causing the indication of an over-temperature event.

Abstract: The present invention provides a method of human-computer interfacing. Force feedback allows intuitive navigation and control near a boundary between regions in a computer-represented space. For example, the method allows a user to interact with a virtual craft, then push through the windshield of the craft to interact with the virtual world surrounding the craft. As another example, the method allows a user to feel transitions between different control domains of a computer representation of a space. The method can provide for force feedback that increases as a user's locus of interaction moves near a boundary, then perceptibly changes (e.g., abruptly drops or changes direction) when the boundary is traversed.

Abstract: A sound synthesis method for modeling and synthesizing dynamic, parameterized sounds. The sound synthesis method yields perceptually convincing sounds and provides flexibility through model parameterization. By manipulating model parameters, a variety of related, but perceptually different sounds can be generated. The result is subtle changes in sounds, in addition to synthesis of a variety of sounds, all from a small set of models. The sound models can change dynamically according to changes in the simulation environment. The method is applicable to both stochastic (impulse-based) and non-stochastic (pitched) sounds.

Abstract: A method of human-computer interfacing provides efficient intuitive controls in a three-dimensional space. The method provides a three-dimensional space, characterized by a z dimension approximately parallel to the user's direction of view, and x and y dimensions approximately orthogonal thereto. A control has x and y coordinate sets, and a z coordinate set that spans a range of values. The range can be infinite, making the control accessible at all depths, or can be a finite range, making the control accessible from that range of depths. Movement of a cursor into the control's region initiates user interaction according to the control. The control depth reduces the precision of depth perception required to find the control. Once the user is in the control region, the effective depth for interaction can be relative to the depth when the user entered, providing control interaction independent of entering depth.

Abstract: The present invention provides a human-computer interface. The interface includes provision of an application domain, for example corresponding to a three-dimensional application. The user is allowed to navigate and interact with the application domain. The interface also includes a personal domain, offering the user controls and interaction distinct from the application domain. The separation into two domains allows the most suitable interface methods in each: for example, three-dimensional navigation in the application domain, and two- or three-dimensional controls in the personal domain. Transitions between the application domain and the personal domain are under control of the user, and the transition method is substantially independent of the navigation in the application domain. For example, the user can fly through a three-dimensional application domain, and always move to the personal domain by moving a cursor near one extreme of the display.

Abstract: A method and apparatus for non-invasively measuring the concentration of an analyte, particularly blood analyte in blood. The method utilizes spectrographic techniques in conjunction with means for equilibrating the concentration of the analyte between the vascular system fluid compartment of the test area and the other tissue fluid compartment. An improved optical interface between a sensor probe and a skin surface or tissue surface of the body containing the blood to be analyzed. Multiple readings during the equilibration period are taken and utilized to show the direction and rate of charge of concentration of the analyte in the blood which is useful in optimizing therapeutic response to the collected data.

Abstract: The present invention provides a method of quickly identifying bioaerosols by class, even if the subject bioaerosol has not been previously encountered. The method begins by collecting laser ablation mass spectra from known particles. The spectra are correlated with the known particles, including the species of particle and the classification (e.g., bacteria). The spectra can then be used to train a neural network, for example using genetic algorithm-based training, to recognize each spectra and to recognize characteristics of the classifications. The spectra can also be used in a multivariate patch algorithm. Laser ablation mass specta from unknown particles can be presented as inputs to the trained neural net for identification as to classification. The description below first describes suitable intelligent algorithms and multivariate patch algorithms, then presents an example of the present invention including results.

Abstract: The present invention comprises a sensing element mounted with a body. The sensing element comprises a portion made with a shape memory alloy. The sensing element mounts with the body, fixedly at two ends. The fixed mounting at one end, however, is configured so that it can be converted to allow a moveable relationship between the body and the sensing element. While the mounting is fixed, the sensing element is prevented from indicating temperature deviations, and the apparatus can be stored and handled freely. After the mounting is converted to provide a moveable relationship, however, a temporary temperature excursion can cause the SMA portion to contract, providing a discernible change in the relationship between the sensing element and the body.

Abstract: A search system and method for controlling multiple agents to optimize an objective using distributed sensing and cooperative control. The search agent can be one or more physical agents, such as a robot, and can be software agents for searching cyberspace. The objective can be: chemical sources, temperature sources, radiation sources, light sources, evaders, trespassers, explosive sources, time dependent sources, time independent sources, function surfaces, maximization points, minimization points, and optimal control of a system such as a communication system, an economy, a crane, and a multi-processor computer.

Abstract: The present invention provides a method of connecting dissimilar finite element meshes. A first mesh, designated the master mesh, and a second mesh, designated the slave mesh, each have interface surfaces proximal the other. Each interface surface has a corresponding interface mesh comprising a plurality of interface nodes. Each slave interface node is assigned new coordinates locating the interface node on the interface surface of the master mesh. The slave interface surface is further redefined to be the projection of the slave interface mesh onto the master interface surface.