The paper industry has long had a need to better understand and control its papermaking process upstream, specifically at the wet end in the forming section of a paper machine. A vision-based system is under development that addresses this need by automatically measuring and interpreting the pertinent paper web parameters at the wet end in real time. The wet-end characterization of the paper web by a vision system involves a four-dimensional measurement of the slurry in real time. These measurements include the two-dimensional spatial information, the intensity profile, and the depth profile. This paper describes the real-time depth profile measurement system for the high-speed moving slurry. A laser line-based measurement method is used with a high-speed programmable camera to directly measure slurry height. The camera is programmed with a profile algorithm, producing depth data at fast sampling rates. Analysis and experimentation have been conducted to optimize the system for the characteristics of the slurry and laser line image. On-line experimental results are presented.

Abstract: Errors are found in the mathematical correlation based on the combined Jouyban-Acree and Modified Apelblat model for describing the variation in the mole fraction solubility of cefpiramide with temperature and solvent composition for the binary aqueous-ethanol solvent system. The equation coefficents given by Tang and coworkers, when substituted into the model equation, do not yield the authors' calculated mole fraction solubilities of cefpiramide.

This paper presents a case study of pressure build-up in some geothermal re-injection wells in Sweden. The geothermal heat plant, in which the re-injection wells are used, has been in operation since the beginning of 1985. Each day since the start of the geothermal plant registration of the injection pressure has been done. The paper describes how a stimulation of the gravel pack outside the well screen can improve the hydraulic performance of the well. The stimulation is done by reversing the flow direction in the well. It is also shown how important it is to have a good well completion in order to receive a positive effect of well stimulation. The paper give example of recordings from two different re-injection wells. The recordings from one of the re-injection wells show that there are serious problems in the well, while the other one shows "normal" hydraulic behavior.

We report on continuing experimental and numerical efforts to obtain steam-water relative permeability functions and to assess effect of heat transfer and phase change. To achieve these, two sets of steady-state flow experiments were conducted: one with nitrogen and water and another with steam and water. During these experiments, a mixture of nitrogen-water (or steam-water) was injected into a Berea sandstone core. At the onset of steady state conditions, three-dimensional saturation distributions were obtained by using a high resolution X-ray computer tomography scanner. By identifying a length of the core over which a flat saturation profile exists and measuring the pressure gradient associated with this length, we calculated relative permeabilities for nitrogen-water flow experiments. The relative permeability relations obtained in this case were in good agreement with those reported by other investigators. Another attempt was also made to conduct a steam-water flow experiment under adiabatic conditions. This experiment was completed with partial success due to the difficulties encountered during the experiment. The results of this experiment showed that a flat saturation profile actually developed over a substantial length of the core even at a comparatively modest injection rate (6 grams per minute) with low steam quality (4% by mass). The …

The understanding of transport processes that occur in naturally fractured geothermal systems is far from being complete. Often, evaluation and numerical simulations of fractured geothermal reservoirs, are carried out by assuming equivalent porous media and homogeneous petrophysical properties within big matrix blocks. The purpose of this paper, is to present a comparison between results obtained from numerical studies of a naturally fractured reservoir treated as a simple porous medium and the simulation of some real aspects of the fractured reservoir. A general conclusion outlines the great practical importance of considering even approximately, the true nature of such systems. Our results show that the homogeneous simplified evaluation of the energy resource in a fractured system, could result in unrealistic estimates of the reservoir capacity to generate electricity.

The Fiji Department of Energy (DOE) has a comprehensive resource assessment programme which assesses and promotes the use of local renewable energy resources where they are economically viable. DOE is currently involved in the investigation of the extent of geothermal resources for future energy planning and supply purposes. The aim is to determine (a) whether exploitable geothermal fields exist in the Savusavu or Labasa areas. the two geothermal fields with the greatest potential, (b) the cost of exploiting these fields for electricity generation/process heat on Vanua Levu. (c) the comparative cost per mega-watt-hour (MWh) of geothermal electricity generation with other generating options on Vanua Levu, and. (d) to promote the development of the geothermal resource by inviting BOO/BOOT schemes. Results to date have indicated that prospects for using geothermal resource for generating electricity lies in Savusavu only - whereas the Labasa resource can only provide process heat. All geophysical surveys have been completed and the next stage is deep drilling to verify the theoretical findings and subsequent development.

A new type of surface micromachined ratcheting actuation system has been developed at the Microelectronics Development Laboratory at Sandia National Laboratories. The actuator uses a torsional electrostatic comb drive that is coupled to an external ring gear through a ratcheting scheme. The actuator can be operated with a single square wave, has minimal rubbing surfaces, maximizes comb finger density, and can be used for open-loop position control. The prototypes function as intended with a minimum demonstrated operating voltage of 18V. The equations of motion are developed for the torsional electrostatic comb drive. The resonant frequency, voltage vs. displacement and force delivery characteristics are predicted and compared with the fabricated device's performance.

The beam-target interaction in heavy ion fusion is theoretically understood, but experimental verification at appropriate beam intensities is not possible using existing accelerators. If fusion-intensity ion beams were to lose significantly less energy in passing through matter than calculated it would increase the cost of heavy ion fusion. In the worst case the cost scaling is such that a 25% decrease in energy loss would increase the cost of the accelerator by roughly 10%. In this paper we show that fundamental considerations place a lower bound on ion energy loss. The lower bound is not significantly less than the expected energy loss obtained from detailed calculations.

The goal of the Laser Safety Officer and any laser safety program is to prevent a laser accident from occurring, in particular an injury to a person's eyes. Most laser safety courses talk about laser accidents, causes, and types of injury. The purpose of this presentation is to present a plan for safety offices and users to follow in case of accident or injury from laser radiation.

By February 1995 the European HDR project at Soultz was operating 6 boreholes: 2 deep hydraulic test wells (GPK-1, 3590 m & GPK-2, 3876 m) and 4 seismic observation wells with depths between 1500 and 2200 m. In 1993 the first section of a deep underground exchanger had been created through massive stimulation (injection of some 45000 m³ of water). Between November 1994 until January 1995 a second deep well, GPK-2, was drilled at the periphery of this exchanger. A complex test programme involving the stimulation of GPK-2 (connecting it to the existing exchanger) and various circulation experiments with different production techniques (flash throttled and unthrottled, submersible pump) and varying injection rates was performed between June and August 1995.

I/S and C/S mixed layers from the geothermal field of Chipilapa (El Salvador) have been studied in details in order to reevaluate their potential use as indicator of the thermodynamic conditions in which they were formed. It is funded that overprinting of clay bearing alteration stages is common. For a given alteration stage, the spatial variation of I/S and C/S mixed layer ininerals is controlled by kinetics of mixed layer transformation and not only by temperature. Clay geo-thermometers cannot give reliable results because the present crystal-chemical states of the I/S and C/S mixed layers is not their initial state, it was aquired during the overall hydrothermal history which post dated the nucleation of smectitic clay material at high temperature. Occurrences of smectites or smectite-rich mixed layers at high temperature in reservoirs is a promising guide for reconstruct the zones in which boiling or mixing of non isotherinal fluids occurred very recently or still presently.

A general analysis of poroelasticity for hexagonal, tetragonal, and cubic symmetry shows that four eigenvectors are pure shear modes with no coupling to the pore-fluid mechanics. The remaining two eigenvectors are linear combinations of pure compression and uniaxial shear, both of which are coupled to the fluid mechanics. The analysis proceeds by first reducing the problem to a 2 x 2 system. The poroelastic system including both anisotropy in the solid elastic frame (i.e., with ''hard anisotropy''), and also anisotropy of the poroelastic coefficients (''soft anisotropy'') is then studied in some detail. In the presence of anisotropy and spatial heterogeneity, mechanics of the pore fluid produces shear dependence on fluid bulk modulus in the overall poroelastic system. This effect is always present (though sometimes small in magnitude) in the systems studied, and can be comparatively large (up to a maximum increase of about 20 per cent) in some porous media--including porous glass and Schuler-Cotton Valley sandstone. General conclusions about poroelastic shear behavior are also related to some recently derived product formulas that determine overall shear response of these systems. Another method is also introduced based on rigorous Hashin-Shtrikman-style bounds for nonporous random polycrystals, followed by related self-consistent estimates of mineral …

Adsorption phenomena are a rich and rather new field of study in geothermal research, in particular at very high temperature. ENEL is interested in the exploitation of geothermal regions with superheated steam, and it is important to understand the behavior of water-rock interaction. We have analyzed in the 170-200 °C temperature range four samples of Monteverdi cuttings; the next experimental effort will be at 220 °C and over in 1996. The first results of the 1995 runs are collected in this paper. We can highlight four main items: 1. At relative pressures over 0.6 the capillarity forces are very important. 2. There is no significant temperature effect. 3. Adsorbed water can be present, and it is able to multiply by a factor of 15 the estimated reserve of super-heated steam only. 4. Pores smaller than 15 Å do not contribute to the adsorbed mass.

The CP-violating parameter sin 2{beta} is directly measured using 110 pb{sup {minus}1} of data accumulated with the CDF detector at the Fermilab {anti p}p Tevatron collider operating at {radical}s = 1.8 TeV. The signal consists of 395 {+-} 31 B{sub d}{sup 0} {r{underscore}arrow} J/{psi} K{sub s} events. Three tagging methods are used to identify the type of B meson at production (B{sub d}{sup 0} or {anti B}{sub d}{sup 0}). From the CP asymmetry, sin 2{beta} is measured to be 0.79 {sub {minus}0.44}{sup +0.41}, consistent with Standard Model predictions. Sin 2{beta} is in the interval 0 {lt} sin2{beta} {lt} 1 at the 93% confidence level.

A numerical simulation model for the Heber geothermal field in Southern California is being developed under a technology transfer agreement between the Department of Energy/Lawrence Berkeley National Laboratory (LBNL) and the California Department of Conservation, Division of Oil, Gas, and Geothermal Resources (DOGGR). The main objectives of the cooperation are (1) to train DOGGR personnel in the use of the TOUGH2PC computer code; and (2) to develop a module compatible with TOUGH2 to investigate the effects of production/injection operations on the ground surface subsidence-rebound phenomenon observed in the Heber geothermal field. Initial-state calibration (undisturbed system) runs are being conducted to calibrate the model.

Previous measurements of acoustic velocities on NEGU- 17 cores indicate that saturation effects are significant enough to cause V_p/V_s anomalies observed in the field. In this study we report on the results of new measurements on core recently recovered from SB-15-D along with some additional measurements on the NEGU-17 cores. The measurements indicate correlations between mechanical, transport, and water storage properties of the matrix which may prove useful for reservoir assessment and management. The SB-15-D material is found to be similar to the NEGU-17 material in terms of acoustic velocities, being characterized by a notably weak pressure dependence on the velocities and a modest V_p/V_s signature of saturation. The effect of saturation on V_p/V_s appears to result in part from a chemo-mechanical weakening of the shear modulus due to the presence of water. Electrical properties of SB-15-D material are qualitatively similar to those of the NEGU-17 cores, although resistivities of SB-15-D cores are notably lower and dielectric permittivities higher than in their NEGU- 17 counterparts. While some limited correlations of measured properties with depth are noted, no clear change in character is observed within SB-15-D cores which can be associated with the proposed cap-rock/reservoir boundary.

This article discusses strong tantalum-to-boron dative interactions in (silox)3Ta(BH3) and (silox)3Ta(ɳ2-B,CI-BCI2Ph) (silox = tBu3SiO)1.

A recent 6-day flow experiment conducted at the Los Alamos National Laboratory's Fenton Hill Hot Dry Rock (HDR) test site in north-central New Mexico has verified that an HDR reservoir has the capability for a significant, and very rapid, increase in power output upon demand. The objective of this cyclic load-following experiment was to investigate the performance of the reservoir in a nominal high-backpressure (2200 psi) baseload operating condition upon which was superimposed greatly increased power production for a 4-hour period each day. In practice, this enhanced production was accomplished by dropping the production well backpressure from the preexisting level of 2200 psi down to about 500 psi to rapidly drain the fluid stored in the pressure-dilated joints surrounding the production well. During the last cycle of this six-cycle test, the mean production conditions were 146.6 gpm for 4 hours at a temperature of 189°C followed by 92.4 gpm for 20 hours at a temperature of 183°C. These flow and temperature values indicate a flow enhancement of 59%, and a power enhancement of 65% during the high-production period. The time required to increase the reservoir power output from the baseload to the peaking rate was about 2 minutes.

By implementing a large-area, gain-stabilized microcalorimeter array on an electron beam ion trap, the electron-impact excitation cross sections for the dominant x-ray lines in the Fe XVII spectrum have been measured as a function of electron energy up to greater than three times the threshold energy, establishing a benchmark for atomic calculations. The results reveal a consistent overestimation by recent calculations of the excitation cross section of the resonance transition, which is shown to be at the root of several long-standing problems associated with modeling solar and astrophysical Fe XVII spectra. The data do not show strong contributions from resonance excitation contrary to recent statements in the literature.

A closed-loop circulation test was conducted from 10 May to 14 July 1995 on the Hot Dry Rock (HDR) reservoir at Fenton Hill, New Mexico after a hiatus of nearly two years. Changes in heat transfer and reservoir volume were investigated and compared to previous circulation tests. Chemical tracers can be used to measure the volume of flow paths in hydrologic systems. Usually, tracers are used in low temperature situations, but the application to high temperature systems has been established for certain tracer compounds. During the 1995 flow testing at Fenton Hill, both a conservative and a non conservative tracer were injected into the reservoir in each of two separate experiments. The purpose was to determine the volume of the most direct flow paths and to estimate the total volume of fractures in the system. The results indicate a relatively static reservoir volume between June and July, yet with an increase in flow dispersion. It can be assumed that channeling of flow did not occur in the main body of the reservoir due to continuous operation. However, a new flow path adjacent to the injection well did develop, and its affect on reservoir flow was investigated using tracer technology. The …

The detection, localization and classification of acoustic sources (targets) in a hostile ocean environment is a difficult problem -- especially in light of the improved design of modern submarines and the continual improvement in quieting technology. Further the advent of more and more diesel-powered vessels makes the detection problem even more formidable than ever before. It has recently been recognized that the incorporation of a mathematical model that accurately represents the phenomenology under investigation can vastly improve the performance of any processor, assuming, of course, that the model is accurate. Therefore, it is necessary to incorporate more knowledge about the ocean environment into detection and localization algorithms in order to enhance the overall signal-to-noise ratios and improve performance. An alternative methodology to matched-field/matched-mode processing is the so-called model-based processor which is based on a state-space representation of the normal-mode propagation model. If state-space solutions can be accomplished, then many of the current ocean acoustic processing problems can be analyzed and solved using this framework to analyze performance results based on firm statistical and system theoretic grounds. The model-based approach, is (simply) ``incorporating mathematical models of both physical phenomenology and the measurement processes including noise into the processor to extract the …

This paper introduces simple model-building evolutionary algorithms (EAs) that operate on continuous domains. The algorithms are based on supervised and unsupervised discretization methods that have been used as preprocessing steps in machine learning. The basic idea is to discretize the continuous variables and use the discretization as a simple model of the solutions under consideration. The model is then used to generate new solutions directly, instead of using the usual operators based on sexual recombination and mutation. The algorithms presented here have fewer parameters than traditional and other model-building EAs. They expect that the proposed algorithms that use multivariate models scale up better to the dimensionality of the problem than existing EAs.

We present the design of a 250 GHz, 400 MW Cyclotron Auto Resonance Maser (CARM) oscillator driven by a 1 KA, 2 MeV electron beam produced by the induction linac at the ARC facility of LLNL. The oscillator circuit is designed as a feedback amplifier operating in the TE{sub 11} mode at ten times cutoff terminated at each end with Bragg reflectors. Theory and cold test results are in good agreement for a manufactured Bragg reflector using 50 {mu}m corrugations to ensure mode purity. The CARM is to be operational by February 1990. 3 figs., 2 tabs.

Tomographic images of tissue phantoms and a sample of breast tissue have been produced from an acoustic synthetic array system for frequencies near 500 kHz. The images for sound speed and attenuation show millimeter resolution and demonstrate the feasibility of obtaining high-resolution tomographic images with frequencies that can deeply penetrate tissue. The image reconstruction method is based on the Born approximation to acoustic scattering and is a simplified version of a method previously used by Andre (Andre, et. al., Int. J. Imaging Systems and Technology, Vol 8, No. 1, 1997) for a circular acoustic array system. The images have comparable resolution to conventional ultrasound images at much higher frequencies (3-5 MHz) but with lower speckle noise. This shows the potential of low frequency, deeply penetrating, ultrasound for high-resolution quantitative imaging.