Darold Wobschall

Esensors Inc.

A method for structural synthesis of Network Capable Application Processors (NCAPs) is proposed. It is based on a method of morphological analysis and synthesis and includes phases of functional analysis, structural synthesis, and search for a set of optimal solutions. The proposed method combines lexicographical criterion of preference (L- criteri...

A software-hardware method of serial interface controller implementation is proposed which includes separate processing of data link and physical layer functions The data link layer functions are implemented in software using a microcontroller (MC), and physical level functions -in hardware using programmable logical device (PLD). The proposed meth...

A miniaturized multi-channel (16) thermocouple DAQ module was designed and tested. The connector and electronics configuration allows positioning of low-noise (<; 1 μv) signal conditioning close to the test area and transmits the data on a high speed Ethernet to a central computer for analysis. It uses the IEEE 1451 smart transducer (open) standard...

A method of precise time synchronization of wireless sensors employing an IEEE 802.15.4 transceiver, and specifically employing the 6LoWPAN protocol, was developed. It uses the IEEE 1588 synchronization standard and the IEEE 1451.5 Smart Transducer Data standard. A Wireless Transducer Interface Module (WTIM) was designed and fabricated. It utilizes...

The universal controller of serial interfaces with separate processing of data link and physical layer functions is proposed. The data link layer functions are implemented in software using a microcontroller, and physical level functions -in hardware using programmable logical device (FPGA or CPLD). It provides minimal utilization of hardware durin...

The NIST-supported IEEE 1451 set of standards is being developed to unify diverse standards by providing a base protocol which allows interoperability between sensor/actuator networks and busses. A key feature of the IEEE 1451 standard is that the data (and meta-data or TEDS) of all transducers are communicated on the Internet with the same format,...

While numerous applications of heterostructures with two-dimensional electron gas (2DEG) in electronics require high-mobility of carriers, slow momentum relaxation creates substantial problems for employing these structures as various detectors of electromagnetic radiation. Significant kinetic inductance of carries does not allow one to use 2DEG-ba...

We investigate THz mixing based on electron heating of two-dimensional electron gas (2DEG) in semiconductor mirobolometers. The 2DEG microbolometers were fabricated from AlGaAs/GaAs heterostructures and have dimensions of 3 - 20mum between the Ohmic contacts and 50µm in width. Significant efforts were made to get low Ohmic contact resistance for ef...

The advantages of the IEEE 1451 smart transducer standard for both wired and wireless networks, in particular for monitoring applications, were discussed. A description of the transducer electronic data sheets (TEDS), a key feature of the standard, and a compiler for its preparation were presented. Several types of transducer interface module (TIM)...

The availability of low power short range RF transmitters and transceivers in the unlicensed band have made small low-cost, battery operated wireless sensors relatively easy to implement, particularly those employing microcontrollers with sleep modes. To extend access to a wider area, even nationally, and to a variety of sensor requires a standardi...

The expansion of smart sensors usage is being slowed by the lack of a universal standard, especially in the wireless area. Recognizing that no single sensor bus or network is likely to dominate in the foreseeable future, the IEEE 1451 set of standards was developed to unify the diverse standards and protocols by providing a base protocol. One featu...

The paper describes two approaches to development of network capable application processors (NCAPs), which support remote online reprogramming and are compatible with IEEE1451 series of standards. The first approach utilizes specialized DS80C400 microcontroller by Dallas Semiconductors, while the second one is based on double-processor architecture...

This paper discusses a method of expanding the standard DALI lighting network into a general purpose sensor network. The DALI (digital addressable lighting interface) was originally intended for communication between a controller and building lighting devices. It is a two-wire bus which allows control of individual lights on the network. A redesign...

This paper presents an implemented system for testing IEEE 1451 standard by using PC computer and an implemented board with various sensors. Communication is according to IEEE 1451 standard through RS232.

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The combined ultrasonic transit time and optical pulse method described here is an improvement over the standard ultrasonic echo by providing a lower signal loss and more precise location of sensor reference points, specifically the transmitting and receiving transducers. The ultrasonic transit time sensor described here uses only a one-way ultraso...

As parts of the IEEE 1451 smart transducer interface standard are completed, or approaching completion, it is desirable to build and demonstrate hardware and software which implements the standard. The purpose of this paper is to demonstrate that, while a full implementation of the standard may be complex, a minimum and useful implementation is not...

A soil moisture sensor was developed which was based on fringing capacitance and the increase in dielectric constant of a soil-water mixture with water content. The frequency shift of an RC oscillator connected to the capacitance sensor electrode was measured by a microcontroller. The data, in IEEE 1451 format, is communicated by a built-in RF tran...

The harmful effects of ionizing radiation, as employed in a variety of medical imaging procedures, have been well studied and documented. To minimize risk to patients, operators must continually assess the dose rate and cumulative dose to the patient at each area of exposure. We have developed a computer graphic dose management display system which...

A resistance temperature detector (RTD) with a digital, networked smart sensor signal conditioner was designed and tested. The data format and internal transducer electronic transducer data sheet (TEDS) is compatible with a revised (RS232) version of the IEEE 1451.2 smart sensor interface standard. A network capable application processor (NCAP) whi...

A digital power meter with a direct Internet access was developed based on the previously reported websensor concept. Line power is measured with a Cirrus Logic CS5460A single-phase bi-directional power-energy IC which has two analog inputs (150 mV RMS full scale), dual A/D converters and a multiplier used to calculate true power and RMS voltage/cu...

A major inhibiting factor to the development of networked digital (smart) sensors is the lack of a single sensor network/bus standard. Over fifty networks are in common use and no single standard is likely to emerge in the near future. In response, a NIST-sponsored initiative has developed the IEEE 1451 sensor interface standard which can be consid...

A local sensor bus for transmitting data from several digital smart sensors to an Internet interface was tested. The master/slave type bus is based on the three-wire SPI (serial peripheral interface) bus, which is built into most microcontrollers. At the sensor end, after A/D conversion of the analog sensor signals and further processing of the dig...

A digital x-ray imager with fill-field screen and high resolution (40 micrometers) was developed. By using commercial, off-the-shelf components to the maximum extent, the production cost of the imager was minimized. A 3x3 array of lens/optical detector modules was fabricated and tested. it is one of the four quarters which make up the fill size ima...

The sections in this article are

Recent developments in CMOS image detectors are changing the way digital imaging is performed for many applications. The replacement of charge coupled devices (CCDs), with CMOS detectors is a desirable paradigm shift that will depend on the ability to match the high performance characteristics of CCDs. Digital X-ray imaging applications (chest X-ra...

Recent developments in CMOS image detectors are changing the way digital imaging is performed for many applications. The replacement of charge coupled devices (CCDs), with CMOS detectors is a desirable paradigm shift that will depend on the ability to match the high performance characteristics of CCDs. Digital X-ray imaging applications (chest X-ra...

The development of an efficient parallel hardware architecture suitable for CCD-mosaic digital mammography has been accomplished. This paper presents this architecture including both the analog and digital portions of the imaging hardware. A two dimensional array of CCD sensors are used to capture the mammographic image synchronously and simultaneo...

Digital mosaic imaging techniques provide a cost effective means to acquiring high resolution images. Constrained mosaic imaging techniques make use of special purpose fiducial patterns in order to define a priori the relation between images on each tile. This 'inter-tile' relation is applied to any images acquired subsequently. A simulation study...

Mosaic architecture based digital mammography is attractive since it offers an affordable and scaleable solution towards obtaining high resolution digital mammograms. Limitations on the clinical usability of the architecture are associated with the x-ray conversion screen utilized and to the methods employed to reconstruct the final digital mammogr...

Investigations in the area of digital mammography have been limited by the resolution of the sensor devices employed. We have proposed a multiple camera or mosaic architecture in which adjacent sensors observe an overlapping field of view. Such a technique can deliver extremely high resolution while simultaneously maintaining a moderate cost for th...

Pre-production prototype of a low-cost, portable, compact digital radiographic imaging device which replaces current film based systems has been constructed and tested. Currently, it is in the process of full utilization for field hospitals where immediate verification of the results is essential. For the particular pre-production unit, image acqui...

A high-resolution, portable, digital x-ray imaging device which replaces current film based systems has been developed. The system is intended to be used in field hospitals where on-line verification is required during treatment. Image acquisition is performed by a 3 X 4 matrix of charge-coupled-device (CCD) imaging sensors which view the output of...

The usefulness of subtraction radiography for detecting small changes in crestal bone is dependent upon achieving reproducible geometry between x-ray beam and patient structures when serial radiographs are taken. This study evaluates 2 methods currently employed to maintain geometric correspondence: 1) a stent-based system which rigidly fixes a cus...

In determining temperature of surfaces by their blackbody emission, simultaneous acquisition of infrared emission at different wavelengths can provide a set of parameters needed to compute the absolute temperature of the object. A graybody model can be used to derive a set of equations that correlates the effects of emissivity variation and reflect...

High-frequency ultrasound is proposed as a means for performing live scan fingerprint imagery. Fundamental ultrasonic imaging concepts and their relationship to imaging the ridge structure of the finger are discussed. The ability to obtain an image of the fingerprint using ultrasound is based on the acoustical impedance difference between human tis...

A remote-transducer telemetry system utilizing an optical link for electrical isolation and EMI (electromagnetic interference) immunity has been developed. The system is capable of interfacing resistance-, capacitance-, and voltage-type sensors. Descriptions of each module making up the system are presented. Experimental results show that a system...

A novel remote transducer telemetry system utilizing an optical link for electrical isolation and EMI (electromagnetic interference) immunity has been developed. This echo sensor telemetry system encodes information by a variable-pulse-width technique. The time between two echo pulses is proportional to, or a function of, the parameters being measu...

An analysis is presented of important, often competing, variables in an optical to electrical (O-E) converter unit. One result describes the nonlinear dependency of output voltage as a function of capacitor load. The charging time as a function of photocurrent, cell saturation current, and load capacitor is illustrated. A particular system, the opt...

A method for improving the efficiency of the conversion of pulsed optical power to electrical power by photovoltaic cells is presented. A fiber-optic echo sensor being developed requires a pulsed power source with a storage capacitor to hold energy for a time after the optical power is turned off. By charging capacitors from each cell individually...

A displacement sensor based on the ratio of fiber-optic light emitted from two fixed position optical fibers into a third, movable fiber connected to a photodetector is described. Square-wave modulated light of opposite phases produces a corresponding square wave at the detector which has zero ac amplitude at the center position and an amplitude pr...

An electronic ion cyclotron resonance detection system was designed and constructed. The ions are excited by sweeping the frequency of the electric field (3–300 kHz) using a sweep frequency generator with a nonlinear sweep voltage in order to maintain an approximately constant mass resolution. Ion detection is accomplished by a bridge with a phase‐...

Field implantable and laboratory sensors for the measurement of moisture in soil based on the increase of soil dielectric permittivity with volume fraction of water were developed. A typical sensor consists of a case containing a high-frequency (31-MHz) oscillator whose frequency determining resonance LC network is coupled to the built-in electrode...

A model of soil composed of a multiphase mixture of solid particles, water, and air voids is proposed from which the complex permittivity, or dielectric constant and conductivity, is calculated. It is based on the Hanai/Bruggelman/Wagner theory of mixtures and considers the ionic conducting water as partly dispersed and partly the dispersing medium...

A sharp rise in the electrical conductance of lipid bilayer membranes was observed following the addition of antigen (bovine serum), antibody (rabbit anti-bovine serum), and complement to the neighboring aqueous phases. At low concentrations, step increases in the conductivity occurred which are consistent with the appearance of about 2.2 nm holes...

Measurements of the steady state polarization of fluorescence from perylene and 9-vinylanthracene embedded in bilayer membranes were performed as a function of temperature. Similar measurements were made when these probes were dissolved in hydrocarbons as model solvents. The effects of cholesterol and n-alkyl alcohol additions to bilayers and head...

Bilayer membranes formed from a decane solution of phosphatidylserine were polarized by an applied potential. An open circuit voltage pulse following the brief short circuit of the polarized membrane was observed if Ca2+ was present in the aqueous phase on both sides of the membrane. This polarization response is proportional to the initial applied...

A meter which features direct readout of the capacitance of artificial lipid bilayer membranes is described. It is basically an ac ohmmeter that has been designed to minimize the commonly encountered series (solution) and input resistance errors. An accuracy of about 3% can be achieved for typical membrane capacitances of 10^-3-10<sup>-1<...

The change in capacitance of cholesterol-hexadecyltrimethylammonium bilayer membranes upon application of relatively high dc and ac potentials was measured as a function of frequency. Capacitance increases proportional to the square of voltage were observed (0.5–1% for 100 mV dc). The amplitude of the ac component of the capacitance variation decre...

The changes in capacitance of hexadecyltrimethylammonium chloride bilayer membranes spanning a circular aperture were determined as a function of time during square wave and sinusoidal expansion. The capacitive response is independent of frequency at very low frequencies but decreases with increasing frequency, and again becomes independent of freq...

Summary A compiler was developed for generating the Transducer Electronic Data Sheets (TEDS), an essential part of the newly developed IEEE 1451.0 open standard for smart transducers. The lack of a compiler for the complex, partially binary TEDS has severely limited the use of the standard previously in spite of the clear virtues of having a univer...

The graphitizing furnace and the elasticity apparatus were finished for ; use in studies on the elastic properties of carbons and graphites at room ; temperature in relation to some fabrication vsriables and the heat conduction of ; graphite at high temperature. A large number of different samples of the type ; soft filler-soft binder were extruded...

In continuation of the work four basic types of carbon were prepared, ; namely from 1) soft filler and soft binder, 2) soft filler and hard binder, 3) ; hard filler and soft binder, 4) hard filler and hard binder. Elastic moduli, ; permanent set, shrinkage and density; electric resistivity and thermal expansion ; coefficient were investigated in de...

The elastic properties of carbons and graphites at room temperature were ; investigated. Physical properties such as Young's and rigidity moduli were ; studied on samples after heat treatment in dry nitrogen. Results are discussed ; and presented graphically. Also, results of permanent set tests in laboratory-; made soft filler rods are presented....

The modulus of ridigity G and Young's modulus E for 1/2-in.-diam. ; calcined coke rods were measured at room temperature after heat treatment to ; various temperatures. The elastic moduli of carbons made from soft filler--soft ; binder and soft filler--hard binder were measured at room temperature as a ; function of heat treatment from 500 to 1700...

Preliminary studies of sounds occurring during carbon stressing, ; apparatus and techniques for determining elastic constants and thermal ; conductivity in graphite, and methods for the direct determination of the Poisson ; ratio are reported. ( For preceding period see NP-6444.) (D. E. B.);

Thesis (M.A.)--State University of New York at Buffalo, 1960. Includes bibliographical references. Typescript.

Incluye índice

Mathematical models of the nerve membrane are investigated in which the individual layers of a bilayer are assumed to have the properties of an electret or ferroelectric. Associated with the electric field induced co-operative dipole realignment are postulated changes in ion permeability and polarization. With certain choices of parameters, the sim...

Through determinations of the widths of ion cyclotron resonance lines as a function of pressure and electric field strengths, the ion—molecule collision cross sections of H+, H2+, H3+, He+, Ar+, N2+, N+, O2+, O2−, and O− were obtained. Agreement with dc mobility data was found. In particular, the minimum in collision frequency for H3+ in H2 at E/P0...

Studies have been made of the ultraviolet and visible absorption spectra of steroid-iodine charge transfer complexes. Iodine complexes with keto-steroids in Freon solution have absorption maxima at 250–270 mμ, and the complexes involving carbon double bonds as donors have maxima at 320–360 mμ. Equilibrium constants range from 0.4 to 12 liters/mole....

Observations were made of ion cyclotron resonance absorption linewidths and shapes at values of E/P up to 400 V/cm·Torr. Three methods of heating the ions are compared. If the detector rf electric field is used to heat the ions, the line shapes are distorted and not well suited for simple interpretation. With the dc heating method, the line shapes...

Studies were made of the ultraviolet and visible absorption spectra of iodine complexes with cyclohexanone and related compounds in Freon solution. Charge-transfer bands occur at 242 mμ for acetone, 249 mμ for 2-cyclohexenone, 233 mμ for cyclohexanol, and 253 mμ for both cyclopentanone and cyclohexanone complexes. Equilibrium constants, extinction...

Observations were made of the cyclotron resonance absorption of O—, O2—, H—, OH—, and H2O— in oxygen containing water vapor. A technique utilizing a circularly polarized rf electric field is described which allows the cyclotron resonance absorptions of negative and positive ions to be distinguished. The production of O2— was found to depend on the...

A sensitive ion cyclotron resonance spectrometer designed to study low energy ion‐molecule interactions in a weakly ionized gas is described. It is capable of determining simultaneously the collision frequency and average concentration of ions having a particular charge‐to‐mass ratio. General design considerations discussed include sensitivity, lin...

The electrical conductivity of sixteen steroids in the solid state was measured as a function of temperature. While too small to measure at room temperature, the exponential increase in conductivity with temperature can be determined at elevated temperatures (70 degrees - 130 degrees C). Most steroids tested had a conductivity of 10(-13) to 10(-15)...

It is shown that the ion cyclotron resonance absorption line in weakly ionized gases may be interpreted to obtain e/m ratio, the number, and the collision frequency of the ions. From the observed linewidths, the collision frequencies of several ions are found as a function of pressure and electric field strength. From these data the ion-molecule co...

A transistorized circuit particularly designed as an output indicator for linear variable differential transformers is given. It is relatively simple to construct, adjust, and operate. The advantages of a phase‐sensitive detector for the measurements of small displacements is discussed. Resolution of the unit is about 0.05 μ; the linearity is about...

Four basic types of carbons were prepared, namely from (1) soft filler-soft binder, (2) soft filler-hard binder, (3) hard filler-soft binder and (4) hard filler-hard binder. The room temperature elastic constants and permanent set for these types of carbons were measured as a function of heat-treatment temperature. A sensitive apparatus using linea...

Measurement of Young's modulus was made on a graphite 1/2-in.-diam. rod for eight different directions of bending. Additional attenuation measurements were made on carbon rods. An effort was made to determine the cause of variance of the thermal conductivity as evidenced upon repeated heating and cooling of the carbon test specimens. (W.L.H.)

Results are presented of a first year of a program designied to study the elastic and the conductive properties of toe carbon-base materials. A high precision apparatus for study of flexure and torsion deformations at room temperature with dependence on iime and the applied stress was developed, and complete stress-strain hysteresis type curves...