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Process-monitoring laboratories in the pulp and paper industry generally use a combination of wet chemical analyses and physical measurements to certify the fitness of a production pulp for a specific end-use. These laboratory tests require time and the effort of trained personnel, limiting their utility for real-time process control. Here we show that Raman probes of unrefined cellulosic pulps, well-suited to the online measurement of in-process materials, can predict the quality attributes of manufactured papers. The accuracy of prediction improves when the covariance is modelled in a reduced measurement space selected by a data-driven, feature-selection technique referred to as a Template Oriented Genetic Algorithm (TOGA). TOGA, combined with discrete wavelet transform (DWT), isolates functional-group features that correlate best with mechanical properties paper derived from refined pulp. Paper makers refine market pulps to build sheet strength using a beating process that decreases freeness as it increases fibre-fibre bonding. Methods demonstrated here predict manufactured sheet properties obtainable after any specified degree of refining from the Raman spectrum of an unrefined pulp. This analysis capacity will enable both vendors of market pulp and makers of sheet paper to specify in advance the amount of beating required to produce a desired product, thereby saving cost and conserving resources.

In the present study, life estimation of accelerated aged insulating papers used in rotating machines is estimated by Arrhenius model. Various types of insulating papers used in rotating machines such as Mylar, Nomex-Mylar-Nomex(NMN), Leatheroid, Dacron-Mylar-Dacron(DMD), Mica Tape, and Kapton are thermally aged at 90°C, 130°C and 170°C with 300hrs duration of each sample. These insulating materials wrapped on copper conductor with single and double layer. Then, breakdown voltage test is performed at each temperature for both single and double layer papers to determine their dielectric strength. Further, correlation analysis between breakdown voltage and different applied temperatures is performed for all paper samples. Popular Arrhenius plot is drawn by short term test data on breakdown voltage for an extrapolation to long term performance of various types of insulating paper used in rotating machines. The results showed that the performance of double layer insulation is almost twice than single layer performance. The aging analysis and testing of insulating papers was performed in TIFAC-Core centre of NIT Hamirpur, H.P., India.

The appearance or printing quality of paper surfaces is mostly characterized by their glossiness, measured with a glossmeter as specular reflectance. The gloss properties of a base paper substrate can be improved after application of a poly(styrene-co-maleimide) nanoparticle coating under pure conditions or in the presence of different vegetable oils. The specular gloss properties of 11 different nanoparticle paper coatings have been determined under 75 degrees and 85 degrees incident light angles, with good relation between values along parallel (machine) and perpendicular (transverse) direction. The gloss properties for the different coatings have been further related to the surface topography. Therefore, the statistical and spatial surface roughness parameters have been studied in detail at two length scales including non-contact profilometry (1 x 1 mm(2)) and atomic force microscopy (2 x 2 m(2)). Based on values of the Rayleigh parameter for non-contact profilometry, the surfaces can be considered as optically rough. The gloss values cannot be directly related to statistical surface roughness parameters. Otherwise, an experimental power-law model for gloss has been proposed as a function of (/Sq) with correlation length and root-mean-square roughness Sq. A best-fit model illustrates that gloss properties of various nanoparticle paper coatings mainly relate to the spatial surface roughness parameters determined from non-contact profilometry. (c) 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 596-610, 2016

Purpose – The purpose of this paper is to evaluate the performance of paper mill plant, which is a very key factor in improving its production. A number of safety challenges can be successfully fixed for a paper mill to continue to make further improvements in reliability, safety and economics. Many incidents in the paper mill plants are frequently caused by human error and equipment failure. Many of the incidents are generally based on poor managerial strategies. These types of errors could have been prevented if safety instructions had been correctly followed and supported in the maintenance system. Design/methodology/approach – A paper mill plant mainly consists four sections namely the head box, wire part, press part and dryer. All these four parts are connected in series configuration. The authors have developed a mathematical model for the plant in which power supply is in standby mode. The designed system can fail in five ways, i.e. by the failure of head box failure, wire part failure, press part failure, dryer failure and power (electricity) failure. So to make proper functioning of paper machine and no interruption in power supply, the authors have considered that power supply is in standby mode. Findings – Using the supplementary variable technique, the Laplace transformations and Markov process theory, the reliability indices of the paper mill plant model are determined. Originality/value – In the present paper, the authors have developed a mathematical model based on a paper plant machine.

Excess application of paper mill sludge (PMS) in field can limit phosphorus uptake by crops because aluminum presented in the sludge can fix or adsorb available phosphorus which is necessary for crop growth. To investigate phosphorus (P) adsorption characteristics of PMS, we examined P adsorption maximum using Langmuir isotherm and P adsorption energy constant using Freundlich isotherm for PMS without alum, PMS with alum, and composted PMS with alum through a laboratory incubation test. The maximum P adsorption capacities were 800 in soil, 47 in PMS without alum and 61 in PMS with alum. P adsorption capacity with alum treatment for PMS increased by 30%. That of PMS compost was 68 and showed that composting increases 11% of P adsorption. Freundlich constant was 22 in check soil, while values in PMS without alum and in PMS with alum were 398 and 426, respectively. After composting, value of PMS compost significantly increased as 1,819. In conclusions, p adsorption capacity for PMS were increased by alum treatment or composting and therefore excess or continuous land application of alum-amended or composted PMS can limit P uptake for crops by reducing available P in sell.

Silver nanoparticle films on glass and paper were prepared using vacuum pulsed laser deposition, and various methods of atmospheric pulsed laser deposition, where ablated material forms a nanoparticle aerosol near the target and is delivered in a gas flow to the substrate. The performance of the films for surface-enhanced Raman spectroscopy (SERS) was investigated using a 10–4 M aqueous solution of rhodamine 6G organic dye. The SERS sensitivity was quantified in terms of the apparent enhancement factor and the signal-to-noise ratio. For the films made by supersonic atmospheric pulsed laser deposition, the apparent enhancement factor was found to be 15,000, which is 150 times higher than the value for a commercial silver nanoparticle paper-based substrate. This study demonstrates the utility of atmospheric pulsed laser deposition for the fabrication of noble metal nanoparticle films, and offers new approaches to tailoring the particle morphology for high SERS performance.

In this paper we study the effect of partial channel state information (CSI) on the performance of dirty paper coding (DPC) schemes. We derive a novel lower bound that shows that the effect of the CSI is upper bounded by the effect of an additive white Gaussian noise with an appropriate variance. The bound is proved using a constructive proof that shows that the predicted rates are achievable using high dimensional lattice modulo precoding schemes. Simulation results demonstrate the usefulness of the bound. The derived bound is useful for the characterization of the interference mitigation performance in partial CSI scenarios such as FDD networks with finite rate feedback, uplink downlink capacity balancing in cooperative cellular networks, etc'.

Recycled paper is extensively used worldwide. In the last decades its market has expanded considerably. The increasing use of recycled paper in papermaking has led to the production of paper containing several types of impurities. Consequently, wastepaper mills are forced to implement quality control schemes for evaluating the incoming wastepaper stock, thus guarantying the specifications of the final product. The main objective of this work is to present a fast and reliable system for identifying different paper types. Therefore, undesirable paper types can be refused, improving the performance of the paper machine and the final quality of the paper manufactured. For this purpose two fast techniques, i.e., Fourier transform mid-infrared (FTIR) and reflectance near-infrared (*IR) were applied to acquire the infrared spectra of the paper samples. *ext, four processing multivariate methods, i.e., principal component analysis (PCA), canonical variate analysis (CVA), extended canonical variate analysis (ECVA) and support vector machines (SVM) were employed in the feature extraction –or dimension reduction– stage. Afterwards, the k nearest neighbors algorithm (k**) was used in the classification phase. Experimental results show the usefulness of the proposed methodology and the potential of both FTIR and *IR spectroscopic methods. Using the FTIR spectrum in association with SVM and k** the system achieved maximum classification accuracy of 100%, whereas using the *IR spectrum in association with ECVA or SVM and k** the system achieved maximum classification accuracy of 96.4%

Modern globalization leads companies into a changing environment with a highly uncertain future development of key drivers of change. Especially, global production networks are affected by uncertainty and dynamic changes. Reactiveness becomes of crucial importance, as the adaptation to environmental conditions is the key to maintain competitive advantages. This article presents an approach for flexible migration planning in global production networks. The focus is on the formulation of a Markovian Decision Process (MDP) that enables the identification of optimal reactions to stochastic changes of key drivers of change. The formulation includes the description of a multi-level modelling approach for global production networks. Furthermore the valuation model of the reward function of the MDP is discussed in detail. Finally, the paper provides a brief description of exemplary optimization results solving the MDP by backward induction.

This research examined the impact of ozonation on lignin-derived and aliphatic compounds ratio (L/A ratio) in secondary pulp and paper mill effluents. Afterwards, adsorption process was employed to investigate the adsorption behavior of ozonized compounds on granular activated carbon (GAC). Phenol and isopentanoic acid (IPA) were practically used as substitute of lignin-derived and aliphatic compounds, respectively. The paper presents the results obtained at laboratory scale with ozone and GAC adsorption as a mean to obtain effluents suitable as reclamation for pulp and paper industry, which requires very stringent limitation in terms of DOC and color removal. The conversion of recalcitrant nature of pulp and paper mill wastewater had been moderate in term of L/A ratio after time interval of ozonation. After ozonation pre-treatment, the adsorption experimental was performed to investigate the adsorption behaviors of phenol and IPA from aqueous solutions onto GAC compared with the decolorization behaviors in real effluents. The best isotherm models fitted to phenol and IPA adsorption on PPHO were determined in the order of Ridlich-Peterson isotherm > Langmuir isotherm > Freundlich isotherm. The IPA was adsorbed strongly on GAC as compared with phenol due to its properties. The maximum adsorption capacity of phenol and IPA on GAC were 0.32 g.g-1 and 0.65 g.g-1, respectively. As result in real effluents, the adsorption capacity of color from the ozonized effluents on GAC was 132.93 ADMI unit.L/mg which was much higher than those of non-ozonized effluents (78.78 ADMI unit.L/mg) and synthetic lignin solutions (55.97 ADMI unit.L/mg).

Drying of sewage sludge is typically modeled as simultaneous heat and mass transfer phenomena. The capability of conventional models to take into account crust formation, cracks, and shrinking is limited. Artificial neural networks (ANNs) are suitable tools for dynamic representation of drying processes; however, obtaining a suitable database is a resource consuming task. Based on the Taguchi method, nine experiments were defined to set up a training database and to develop an ANN model. A high Pearson correlation coefficient was verified when comparing the drying kinetic curve generated by the ANN model with the one obtained during the validation experiments.

In this paper, two novel techniques developed by the authors to measure certain quality variables in paper manufacturing are described. These methods are based on the new online image sensors for digital image processing of paper samples. The techniques use the two dimensional Fourier transform of the original images to estimate basically two variables: the floc size distribution in paper formation and creping of tissue paper. In the first case, a new method to estimate the floc size distribution in paper is presented. The method computes only a reduced portion of the spectrum to determine, in frequency, the floc sizes present. The technique to measure creping gives the degree of roughness that has been induced on the tissue paper by looking also at its power spectra distribution. This characteristic is essential in determining the smoothness of tissue paper. >

The aerodynamic design of micro air vehicles is challenging since previous studies have shown that the aerodynamic efficiency of airfoils and wings decreases substantially at low Reynolds-numbers. While many MAV approaches investigate biological designs, here a study is conducted on the aerodynamics of paper airplanes, which fly in the same Reynolds-number range as MAV, but have the advantage of simplicity compared to biological counterparts. Flow visualizations and force measurements in a water tunnel as well as large-eddy simulations are presented on one of the simplest paper airplane design: the dart. The results show that the high-sweep delta design of such an airplane provides high lift coefficients at low Reynolds-numbers. Furthermore, the centerfold of the airplane as a mean to improve the aerodynamic performance is identified.

SUMMARY Fiber orientation is a criterion used to ascertain the manufacturing district and manufacturing technique of ancient paper as a material of cultural properties. Image analysis using fast Fourier transform with suitable modifications was demonstrated to be an applicable and nondestructive method to determine the orientation angle and anisotropy. In order to improve its accuracy, two new procedures—the binarization process of the microscopic images of the paper surface and precise calculations of the average Fourier coefficients as an angular distribution by linear interpolation—have been introduced to the existing procedures. This analytical method was applied to digital optical micrographs of paper surfaces. As predicted, the method was able to distinguish among laboratory handsheet, copier paper, Japanese paper, and wood-containing paper in terms of the papermaking processes. Traditionally manufactured Korean and Japanese papers showed their own characteristic orientation behavior in accordance with the motion of the bamboo wire in papermaking.

Modal analysis was done to steel shaft and rubber shaft, and their top ten orders of nature frequency were obtained. The lowest nature frequency of steel shaft is 64HZ and the rubber steel’s is 2.2463HZ. Doppler vibration measurement was done to main shaft of paper advance mechanism and the time domain signal and frequency domain signal were obtained when the rotational speed is 80, 160, 240, 320, 400 Rpm. The frequency and amplitude were obtained by signal analysis. It proves that the nature frequency of steel main shaft is much higher than measuring result, but the seventh and eighth order nature frequency of rubber material is in accord with measuring result of laser doppler vibration.

IR monitoring is a basic tool for quality control and predictive maintenance in the paper industry. There are also other possible interests, e.g. measurements of temperature profiles of high speed production lines. The first possibility to use IR for the above mentioned use appears to be applications of glass heat treatment in on line production. At this time there is a lot of interest to be able to measure temperature profiles from a fast moving surface (e.g. in paper machines) with velocities like 10 - 20 m/s. Normal low speed line scanners typically give scanning speed of 50 Hz which in this case means 20 m/s/50 Hz equals 40 cm resolution. The obtained resolution is not normally high enough. To have more accurate vision from the studied surface IR camera line scanning was proposed to be a solution with line scanning frequencies of 8000 Hz which would provide resolution of 20 m/s/8000 Hz equals 0.25 cm between surface points. It is a well-known fact that all undesired frequencies in paper transfer systems disturb the uniform paper drying process which in some cases is the basic reason for low quality coating or even broken paper line. The possibility to detect these drying problems with IR frequency analysis will give a new way to control the paper drying process. With IR analysis it is possible to get information about temperature distributions along the paper track. Using a well established frequency analysis as a tool, the error estimations are obtained. In most cases an open-roll image from paper track is very desirable because there are no existing wide area measurement systems for this purpose. The careful analysis of this new method is given in the manuscript.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

To achieve the goal of high production and hence more profit in an organisation, each system/subsystem must remain operative for long duration. The industrial systems are complex in nature, configuration and capital oriented and so it is very difficult to analyse their failure pattern. The available information about these equipments is imprecise, incomplete, vague and conflicting. Therefore, management decisions are based on experience. The objective of this paper is to quantify the uncertainties which make the decision more realistic and generic for the considered industrial system. The study is conducted in a medium sized paper industry, comprised of subsystems namely – chipping, feeding, pulping, washing, screening, bleaching, paper production system, etc., arranged in a series configuration. Pulping system, the main functionary part of the paper industry, is the subject of present discussion. An interaction among the operative equipments has been developed using Petri net model and the steady state behaviour of the equipment has been analysed. The results will be helpful for reallocating the resources and for achieving the targeted goal of higher profit.

In this paper, it find out the way of splice the scraps of paper which come from the same page of the printed text documents together by MATLAB software. Firstly, the image is made to the value of two forms of matrix, to establish the algorithm of the scraps of paper splicing restoration model by analyzing all matrix data of the scraps of paper based on the Grey system theory and Pearson correlation coefficient as the test variable. Then the fragments were spliced restoration by MATLAB software. Because of the computer matching has certain systematical error, it must write the time node intervention and intervention with the appropriate human intervention in this paper. Finally, it gains some parts of complete Chinese pictures and tables according to the recovery results.

With the increasing closure of white water circuits in paper mills, breaks in the sheet of paper have become a system-wide disturbance. Upon recognizing that such breaks can be modeled as a Markov chain type of process which, when interacting with the continuous mill dynamics, yields a jump Markov model, jump linear theory is proposed as a means of constructing white water and broke recirculation strategies which minimize process variability. Reduced process variability comes at the expense of relatively large swings in white water and broke tank levels. Since the linear design does not specifically account for constraints on the state space, under the resulting control law, damaging events of tank overflows or emptiness can occur. A methodology, mainly founded on the first passage-time theory of stochastic processes, is proposed to choose the performance measure design parameters to limit process variability while maintaining sufficiently long mean times between incidents of fluid in broke and white water tanks either overflowing or reaching dangerously low levels. The heart of the tuning approach is an approximation technique for evaluating mean first passage-times of the controlled tank height processes. This technique appears to have an applicability which largely exceeds the problem area it was designed for.

The aging of oil-paper insulation in power transformers may cause serious power failures. Thus, effective monitoring of the condition of the transformer insulation is the key to prevent major accidents. The purpose of this study was to explore the feasibility of confocal laser Raman spectroscopy (CLRS) for assessing the aging condition of oil-paper insulation. Oil-paper insulation samples were subjected to thermal accelerated ageing at 120 °C for up to 160 days according to the procedure described in the IEEE Guide. Meanwhile, the dimension of the Raman spectrum of the insulation oil was reduced by principal component analysis (PCA). The 160 oil-paper insulation samples were divided into five aging stages as training samples by clustering analysis and with the use of the degree of polymerization of the insulating papers. In addition, the features of the Raman spectrum were used as the inputs of a multi-classification support vector machine. Finally, 105 oil-paper insulation testing samples aged at a temperature of 130 °C were used to further test the diagnostic capability and universality of the established algorithm. Results demonstrated that CLRS in conjunction with the PCA-SVM technique provides a new way for aging stage assessment of oil-paper insulation equipment in the field.

Problem formulations and solution procedures of production planning and inventory management for manufacturing systems under uncertainties is discussed. Markov decision processes and controlled Markovian dynamic systems are used in the models. Considering an inventory problem in discrete time and formulating it by a finite-state Markov chain lead to a Markov decision process model. Using the policy-improvement algorithm yields the optimal inventory policy. In controlled dynamic system modeling, the random demand and capacity processes involved in planning are described by two finite-state continuous-time Markov chains. Such an approach enables us to embed the randomness in the differential equations of the system. The optimal production rates that minimize an expected cost are obtained by numerically solving the corresponding Hamilton–Jacobi–Bellman (HJB) equations. To overcome the so-called curse of dimensionality, frequently encountered in computation, we resort to a hierarchical approach. Illustrative examples using data collected from a large paper manufacturer are provided. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2877–2890, 2004

Use of Debye Model to analyze insulation response, recorded from high voltage power equipments, is common among researchers. Available literature shows that relaxation characteristics of dipoles present in oil and paper have different relaxation times. This implies oil and paper condition influence separate branches in Debye Model. In the present work a new aging sensitive performance parameter is introduced. The parameter can be evaluated from Transfer Function, TF D (S) of Debye Model. The performance parameter mentioned above is one of the zeros (Z 1 ) of TF D (s).T he capability of Z 1 as an insulation condition sensitive parameter is tested on samples constructed in the laboratory.

Existing literature shows that lower time constant branches of insulation model represent condition of oil, whereas higher time constant branches are influenced by the condition of solid insulation. It is possible to assess the condition of oil-paper insulation by identifying the parameters of insulation model. It is understood that in addition to aging and moisture, factors like insulation geometry also affect the values of the branch parameters of insulation model. This implies parameters evaluated from one insulation model has limited potential in assessing the condition of a different transformer, even if the loading history and power rating of the two units are similar. The present paper introduces a performance parameter, which is less sensitive to insulation geometry. The parameter can be evaluated from the Transfer Function of the insulation model. It is shown that the parameter is influenced by condition of both oil and paper insulation. The performance of the proposed parameter is first tested using laboratory sample and then using data obtained from several real life power transformers.

Advances in instrumentation are making Raman spectroscopy the tool of choice for an increasing number of chemical applications. For example, many recalcitrant industrial process monitoring problems have been solved in recent years with in-line Raman spectrometers. Raman is attractive for these applications for many reasons, including remote non-invasive sampling, minimal sample preparation and tolerance of water. To a lesser extent, Raman spectroscopy is beginning to play a significant role in environmental analysis for the same reasons. At present, the environmental applications typically apply only to the most contaminated situations due to the still relatively high limits of detection. However, some emerging sampling technologies hold out the promise that Raman may soon be more widely applicable to the analytical chemistry of potable water. Herein we discuss these recent advances, summarize some examples of environmental applications to aqueous systems and suggest avenues of future developments that we expect to be most useful for potable water analysis. Also, a simplified, but detailed, theory of normal Raman scattering is presented. While resonance-enhanced Raman spectroscopy, surface-enhanced Raman spectroscopy and non-linear Raman techniques are briefly discussed, their theories and instrumental configurations are not addressed. Also, this article deals primarily with the modern dispersive Raman experiment (as opposed to the Fourier transform Raman experiment), because it seems most suited for potable water analysis. The goal of this article is to give the environmental scientist with no specialized knowledge of the topic just enough theory and background to evaluate the utility of this rapidly developing analytical tool.

The paper describes advances made in a computer method for the detection of paper shrinkage during the drying stages. The technique is based on two-dimensional Fourier transformations used to detect those periodic marks left on the paper by the wire during the formation stage. These marks are obtained from images of paper taken by low-cost CCD cameras for a later matching with those of the wire. Differences in separation of lines for the two cases are due to paper shrinkage. Finally some comments on hardware considerations of the sensor design and potentials of the method for the paper and graphic industry are given

Rotating stall and surge have been stabilized in a transonic single-stage axial compressor using active feedback control. The control strategy is to sense upstream wall static pressure patterns and feed back the signal to an annular array of twelve separately modulated air injectors. At tip relative Mach numbers of 1.0 and 1.5 the control achieved 11 and 3.5 percent reductions in stalling mass flow, respectively, with injection adding 3.6 percent of the design compressor mass flow. The aerodynamic effects of the injection have also been examined. At a tip Mach number, Mtip, of 1.0, the stall inception dynamics and effective active control strategies are similar to results for low-speed axial compressors. The range extension was achieved by individually damping the first and second spatial harmonics of the prestall perturbations using constant gain feedback. At a Mtip of 1.5 (design rotor speed), the prestall dynamics are different than at the lower speed. Both one-dimensional (surge) and two-dimensional (rotating stall) perturbations needed to be stabilized to increase the compressor operating range. At design speed, the instability was initiated by approximately ten rotor revolutions of rotating stall followed by classic surge cycles. In accord with the results from a compressible stall inception analysis, the zeroth, first, and second spatial harmonics each include more than one lightly damped mode, which can grow into the large amplitude instability. Forced response testing identified several modes traveling up to 150 percent of rotor speed for the first three spatial harmonics; simple constant gain control cannot damp all of these modes and thus cannot stabilize the compressor at this speed. A dynamic, model-based robust controller was therefore used to stabilize the multiple modes that comprise the first three harmonic perturbations in this transonic region of operation.

Strong demand exists for a non-contacting paper caliper measurement which can be used as an input to a paper thickness control system. Caliper sensors requiring sheet contact suffer from errors related to dirt or coating build up and from high maintenance costs related to wear. These sensors can also damage the product by picking holes and marking sheets. Details of an on-line measurement device which employs two opposed laser displacement sensors and an inductive displacement sensor are presented. The sheet is held perpendicularly to the sensors with a Coanda air clamp. Dust and temperature control features which enable the sensor to operate reliably in an industrial environment are discussed. Results of production trials of this sensor are presented. Sub-micron profile agreement to lab and contacting caliper measurements has been demonstrated on light sheets. Results are presented of measurements on a wide range of paper grades from coated and uncoated light sheets to coated board.

Many industrial processes are in cascade configuration in which the material being processed goes through a sequence of processing units. The output of an upstream processing unit is fed into the input of the unit downstream. In many cases, the variables of interests are only available via related uncertain surrogate measurements in the all the upstream stages, and directly measured at the output of the last stage. The problem of controlling such systems by adaptively calibrating the surrogate measurement model and the use of a pre-emptive control strategy was studied in [9]. In this paper, the unknown actuator dynamics is taken into account in the adaptive calibration and pre-emptive control as well. A Lyapunov based nonlinear control algorithm is derived. The proposed control algorithm is applied to a vacuum dewatering process in paper manufacturing industry. Simulation results show that the proposed control strategy can regulate the exiting moisture content of each unit at the desired value.Copyright © 2009 by ASME

In this paper, an approach for control-oriented high-frequency turbomachinery modeling previously developed by the authors is applied to develop one-dimensional unsteady compressible viscous flow models for a generic turbojet engine and a generic compression system. We begin by developing models for various components commonly found in turbomachinery systems. These components include: ducting without combustion, blading, ducting with combustion, heat soak, blading with heat soak, inlet, nozzle, abrupt area change with incurred total pressure losses, flow splitting, bleed, mixing, and the spool. Once the component models have been developed, they are combined to form system models for a generic turbojet engine and a generic compression system. These models are developed so that they can be easily modified and used with appropriate maps to form a model for a specific rig. It is shown that these system models are explicit (i.e., can be solved with any standard ODE solver without iteration) due to the approach used in their development. Furthermore, since the nonlinear models are explicit, explicit analytical linear models can be derived from the nonlinear models. The procedure for developing these analytical linear models is discussed. An interesting feature of the models developed here is the use of effective lengths within the models, as functions of axial Mach number and nondimensional rotational speed, for rotating components. These effective lengths account for the helical path of the flow as it moves through a rotating component. Use of these effective lengths in the unsteady conservation equations introduces a nonlinear dynamic lag consistent with experimentally observed compressor lag and replaces less accurate linear first-order empirical lags proposed to account for this phenomenon. Models of the type developed here are expected to prove useful in the design and simulation of (integrated) surge control and rotating stall avoidance schemes.

This paper presents an optimization strategy for a broke system design and operation in papermaking process. A multiobjective stochastic optimization model is presented featuring (i) a stochastic two-state Markov process based submodel for the broke tower, (ii) an operational submodel for the optimization of the broke dosage, and (iii) a multiobjective design problem. An efficient optimization strategy is also proposed involving a quadratic optimization step for the operational subproblem and an effective multiobjective design optimization step.

Doppler Global Velocimeters (DGV) requires a narrow bandwidth laser beam which can be accurately tuned to a desired frequency. One laser used for this application is an ND-YAG which is seeded using a laser diode. By adjusting the laser diode output, the frequency of the ND-YAG laser beam can be modified. This technique also narrows the bandwidth of the laser frequency to below 100 MHz. Monitoring this output is difficult due to the 9 ns pulse duration which makes normal interferometry techniques ineffective for the 10 to 20 MHz frequency resolution required. This paper will describe a system constructed to monitor the frequency in real time which can be used in conjunction with a DGV system to correct for laser frequency drift. The particular ND-YAG system response and stability will be presented and discussed in relationship to DGV system accuracy.Copyright © 2008 by ASME

Many industrial processes are in cascade configuration in which the material being processed goes through a sequence of processing units. In many cases, direct in-process measurements of the relevant variable are not available at all but at the last processing unit surrogate or model based soft measurements in which the relevant in-process variables are inferred from other measurements would be useful in these situations. Models necessary for the surrogate measurements however, are often not accurately known. In this paper, we propose a control method in which the surrogate measurement models are adaptively calibrated and the surrogate measurements are used for in-process feedback. The control law is developed in the context of moisture content control for paper manufacturing via successive vacuum dewatering. A Lyapunov based algorithm is derived and proved. Simulation results show that the proposed control strategy can regulate the exiting moisture content of each box at the desired value.

The aim of this investigation is to develop the minute flow measuring technology to calibrate sonic nozzles at the low flow rate and low pressure without the expensive primary standard system. With this calibrated sonic nozzles, calibration service of flow meters to industry will be available. In this experiment, eight sonic nozzles with the throat diameter of 0.2 mm were manufactured according to the specifications of ISO 9300, and then four out of eight nozzles, which have most close values of the rate of discharge coefficients for a pair of nozzles, were selected. At first, all the four nozzles for the stagnation pressure range of 200∼600 kPa were calibrated in the standard system. Then, for the rest of the whole experiments, the step-down procedure was adopted to reduce the stagnation pressure range of the nozzle, 3∼600 kPa. It was proven that the step-down procedure can be done over and over with small additional uncertainty.Copyright © 2008 by ASME

Ultrasound techniques for flow investigation have been extensively developed for several years. Many methods have reached a level of maturity that allows widespread and still growing clinical use. Recently, new exciting developments have been introduced by the combination of Doppler techniques with advanced (e.g. plane wave) imaging methods. Therefore, a comprehensive review of the current state-of-the-art ultrasound methods applied to flow measurement and imaging becomes relevant.

Galileo Galilei once said in the 17th century that "anyone who understands geometry can understand everything in this world." But he had never heard of molecules, atoms or even smaller components. These days we would imitate Galileo by saying "anyone who understands the processes inside atoms and molecules understands the world." This nano world has its own unique appeal: something that is invisible to the naked eye, yet has dimensions that the mind still requires images/comparisons to understand, is a source of tremendous fascination. Even if we are a long way from understanding these processes, we now know one thing for certain: these days, decisive technological progress is made in the world of the minuscule. Specific examples of this come from the areas of gene technology, materials research and electronics on a daily basis. As a result, nanotechnologies have become the focal point of research and development - not only in industry but also in politics. For example, in March 2004, the German Federal Government launched the German innovation initiative for nanotechnology under the slogan “Nanotechnology Conquers Markets”. According to a press release by the German Federal Ministry of Education and Research (BMBF), euro 200 million in funding will be made available to four leading-edge innovations over the next four years. However, there is still some debate about how to define the term “nanotechnology”. While some see the essence of nanotechnology as the creation of a large entity from the minutest components by means of partly self-organizing processes, such as car paint consisting of nanoparticles, others simply regard the scale of particles or structures as the area of crucial significance. Scientists set a value of 100 nanometers as the "limit". A BMBF brochure argues: "It [nanotechnology] does not, therefore, represent a basic technology in the classical sense-one with clearly defined parameters. Instead, it describes a new interdisciplinary approach that will help us to make further progress in the fields of biotechnology, electronics, optics and new materials." There seems to be no end to the debate, with definitions continuing to clash and overlap. One thing is for sure, though, and that is the importance of nanotechnologies as a driving force for technological progress.

With the increasing closure of white water circuits in paper mills, breaks in the sheet of paper have become a systemwide disturbance. Upon recognizing that such breaks can be modelled as a Markov chain type of process which when interacting with the continuous mill dynamics yield a jump Markov model, jump linear theory is proposed as a means of constructing white water and broke recirculation strategies which minimize process variability. A methodology is proposed to choose the performance measure design parameters so as to keep mean time between incidents of fluid in broke and white water tanks overflowing, or reaching dangerously low levels sufficiently long.

Linear quadratic jump regulation theory can be used to derive white water and broke recirculation strategies which minimize process variability. Reduced process variability comes at the expense of relatively large swings in white water and broke tanks levels. Since the linear design does not specifically account for constraints on the state-space, under the control law damaging events of tanks overflow or emptiness can occur. A methodology mainly founded on the first passage-time theory of stochastic processes is proposed to choose the performance measure design parameters to limit process variability while maintaining mean time between incidents of fluid in broke and white water tanks either overflowing, or reaching dangerously low levels, sufficiently long. The corresponding approximation technique involved in evaluating mean first passage-times of the controlled stochastic processes appears to have an applicability which largely exceeds the problem area it was designed for.

This book should prove to be the definitive work explaining van der Waals forces, how to calculate them and take account of their impact under any circumstances and conditions. These weak intermolecular forces are of truly pervasive impact, and biologists, chemists, physicists and engineers will profit greatly from the thorough grounding in these fundamental forces that this book offers. Parsegian has organized his book at three successive levels of mathematical sophistication, to satisfy the needs and interests of readers at all levels of preparation. The Prelude and Level 1 are intended to give everyone an overview in words and pictures of the modern theory of van der Waals forces. Level 2 gives the formulae and a wide range of algorithms to let readers compute the van der Waals forces under virtually any physical or physiological conditions. Level 3 offers a rigorous basic formulation of the theory.

Techniques for absolute interferometric measurement of surface figure are often used for qualification of spherical surfaces specified as (lambda) /20 PV or better. As the radius of curvature increases, these techniques become impractical due to the length of cavity required, and environmental effects. Our approach has been to certify a reference surface with a shorter, i.e., manageable radius of curvature, and then to proceed through a series of measurements with surfaces of increasing radius, while maintaining a manageable cavity length. At each stage, the `reference' data from the previous stage is subtracted from the new measurement in order to better approximate the actual surface. The requirements of spatial registration and image magnification are stringent if one is to use the phase measured data directly. This process can be simplified if one uses a polynomial fit to the surface, e.g., Zernikes. The technique is described for the qualification of a surface with an 8 meter radius of curvature and is examined for sources of error.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Past and current replacement models with applications to the marine industry for determining the optimum maintenance strategy are discussed. A new approach to multi-item replacement under budget constraints is presented. This approach considers all replacement decisions of an entire ship fleet. (or all component replacements of a single ship) simultaneously. A Lagrangian methodology for the replacement problem is also described.

The core of the relationship between science and technology in Europe can be traced back to Galileo Galilei (died 1642) or Leonardo da Vinci (died 1519). Thus progress in scientific knowledge to the heliocentric world system essentially advanced through improved Dutch telescope technology and excellent lens grinding and also conversely the then new scientific model of the cosmos could be used directly for maritime navigation. Science and technology appear to be closely interlinked. Owing to the connection — obvious even then — between technical change and economic prosperity, early innovations were in no doubt as the importance of science to economic and social advance was self.

Publisher Summary This chapter presents experiments on deformations of paper in stacks, in which sheets were conditioned at a fixed humidity and then printed with a screen line plate by means of a Vandercook proof press. The prints were stacked progressively during printing. The stack was exposed to another humidity for a time and then, a second color was printed upon the first one, from the same plate. From the interference of the two line patterns, it was possible to measure deformation of the paper. Every sheet was measured and the results for an offset paper, a conventional coated paper, and a machine-coated paper are presented in the chapter. The change in dimension is given on the abscissa in units of 0.1 mm/m. The trials were made on three papers: (1) an offset paper, (2) a conventional coated paper, and (3) a machine-coated paper. The results show that the deformation was greater in the transverse direction than in the longitudinal direction and the deformations were not the same whether the transverse direction or the longitudinal direction was parallel to the cylinder axis; this effect shows that the press has a laminating action.

In this paper, we deal with the microstrip gap that should be analyzed in three-dimensional space. The time variations of the electric field at each surface of the stripline having a finite metallization thickness are analyzed. Our method of analysis is based on both an equivalent circuit of Maxwell's equations and Bergeron's method. The former has advantages in the vector analysis by using all electromagnetic components. The latter has advantages in the time-domain analysis of the field. Therefore, our method can analyze field variations in three-dimensional space and time. We present the time variation of the instantaneous electric-field distributions below the strip, at the side of the strip, and at the gap end surface. These results show how the steady-state field distribution grows in the gap.

The paper describes a series of experiments that were conducted on a compressor blade of conventional geometry, in a low-speed research compressor, to determine the effect of Reynolds number on the performance of (1) an isolated rotor blade row when the free-stream turbulence is low, (2) the isolated rotor at a higher level of turbulence, and (3) the rotor row when unsteadiness is introduced by a set of inlet guide vanes of zero camber and zero stagger. In each case the axial velocity ratio at mid-span was measured and tests were carried out under similar conditions on a two-dimensional cascade of blades using a wind tunnel with porous side walls. The compressor results indicate that there are significant Reynolds number effects under these conditions, and the comparison with the cascade results demonstrates that there is a difference in performance between the rotating row and the cascade.

This paper constitutes a review of the research work completed at the Computing Center of the USSR Academy of Sciences dealing with the theory of optimal orbit transfers for space vehicles powered by low-thrust rocket engines.

A. E. Kennelly: Turning to the paper by Dawes and Hoover, it seems to me that the great force of that contribution lies in the fact that a bridge has been developed which employs a vibration galvanometer, with all the delicacy and precision that the vibration galvanometer affords, so that instead of having to employ a relatively great length of cable dielectric for test, it is sufficient to have only, say, a couple of meters, provided that the particular couple of meters shall represent fairly well, the whole length of a cable under consideration.