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2. A return to an old paper: 'Tests of separate families of hypotheses'
- Author
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Cox, D. R.
- Published
- 2013
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3. Quasi-Likelihood and Optimal Estimation, Correspondent Paper
- Author
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Godambe, V. P. and Heyde, C. C.
- Published
- 1987
- Full Text
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4. Direct and indirect generation of waste in the Spanish paper industry.
- Author
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Ruiz Peñalver, Soraya María, Rodríguez Molina, Mercedes, and Camacho Ballesta, José Antonio
- Subjects
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WASTE management , *PAPER industry , *WASTE paper , *ESTIMATION theory , *FORESTS & forestry , *ECONOMIC models , *ECONOMICS - Abstract
Highlights: [•] The waste generated by the suppliers of the Spanish paper industry is estimated. [•] An Economic Input Output Life Cycle Assessment Models (IO-LCA) is employed. [•] No direct relationship between impact on output and on waste generation was found. [•] The major contributors to waste generation were mining and forestry. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
5. Overcoming business model uncertainty in a carbon dioxide capture and sequestration project: Case study at the Boise White Paper Mill.
- Author
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McGrail, B.P., Freeman, C.J., Brown, C.F., Sullivan, E.C., White, S.K., Reddy, S., Garber, R.D., Tobin, D., Gilmartin, J.J., and Steffensen, E.J.
- Subjects
CARBON sequestration ,GREENHOUSE gases ,BUSINESS models ,EMISSIONS (Air pollution) ,BIOMASS ,ESTIMATION theory ,PAPER mills - Abstract
Abstract: Carbon capture and storage (CCS) is one of a suite of technology options that might play a significant role in reducing greenhouse gas emissions. However, outside of traditional enhanced oil and gas recovery operations with a well established business model, CCS project deployments are struggling with adoption of a federal or international climate policy driver appearing unlikely for the foreseeable future. As part of a feasibility study for an industrial CCS project at the Boise White Paper mill in Washington State, a business model and CCS system design was developed that provided financial surety for the project developers while recognizing that uncertainty in revenue forecasts for CO
2 storage would persist for the foreseeable future. Key to the business model was installation of a new 37MWe biomass-fueled power island at the plant that would replace antiquated boilers and that could still supply the necessary steam to run pulp and paper production operations when capturing CO2 emissions under favorable market conditions for monetizing CO2 storage credits. Under unfavorable market conditions, CO2 capture would be suspended and excess power generated from the plant would reduce external electrical energy purchases required for paper mill operations. The net CO2 reduction for the project versus current operations is 1.0MMT of CO2 per year with the CCS system online, and 139ktons per year with the CCS system offline due to reduced natural gas co-firing. So, both operational modes offered a significant net reduction in CO2 emissions. Based on assumptions regarding electricity and natural gas pricing, and CO2 storage revenue generated through an open market mechanism priced at $15 per metric ton CO2 , the payback period for the project capturing 0.5MMT/yr (62% of total CO2 production) was estimated at 6.7 years versus 7.4 years with the CCS system offline. Geologic storage was evaluated in the deep flood basalt formations that dominate the storage capacity in Eastern Washington. Sub-basalt sediments were also examined at the site to provide alternative or supplemental storage capacity in the event that storage in the basalt sequences did not prove technically or economically feasible. [Copyright &y& Elsevier]- Published
- 2012
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6. Linking process variables and newsprint properties in Mazandaran Wood and paper Industries.
- Author
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Hadi Moradian, Mohammad and Resalati, Hossein
- Subjects
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NEWSPRINT , *PAPER industry , *NEWSPAPERS , *STATISTICAL correlation , *ESTIMATION theory - Abstract
Pulp and paper industries have provided great research opportunities to control systems. The objective of this study was to investigate the relationships between 80 process variables of CMP tower and stock preparation, and 17 newsprint quality properties in Mazandaran Wood and Paper Industries (MWPI). After the preparation of two suitable data series considering the time needed for pulp to paper, the relations between process dependent and newsprint independent variables were determined using partial least squares (PLS) regression. As a result, two PLS models were developed. The first model with 4 latent vectors categorized and related CMP tower variables and the second one, through 8 latent vectors connected stock preparation variables with paper properties. PLS regression coefficients determined how much the most influencing process variables impact each paper properties [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
7. Estimation of energy saving potential in China's paper industry.
- Author
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Lin, Boqiang and Moubarak, Mohamed
- Subjects
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PAPER industry , *ENERGY conservation , *ESTIMATION theory , *ECONOMIC equilibrium , *ENERGY consumption - Abstract
Abstract: The objective of this paper is to estimate the energy saving potential in China's paper industry by determining energy intensity under different scenarios. Cointegration model and stability test are applied to formulate the equilibrium equation. Results show that energy price, industry structure, profit margin and technology have significant impact as they are negatively correlated to changes in energy intensity. Three scenarios (BAU (business as usual), intermediate and active) are designed to estimate the future trend of energy intensity in paper industry. In 2010, the energy intensity (energy consumption per unit of value added) was 4 tce/10,000 RMB, and by the scenarios it is expected to considerably decline. According to the BAU (business as usual) scenario, the energy intensity will decrease to 2.56, 1.43 and 0.70 tce/10,000 RMB by 2015, 2020 and 2025, respectively. With respect to the intermediate scenario it is expected to drop further to 0.44 tce/10,000 RMB. Yet by the active scenario, the energy intensity is expected to considerably decline to 0.36 tce/10,000 RMB by 2025. Using the BAU forecast as a baseline, the quantity of energy savings is estimated to be 185.6 billion tce by 2025. Considering this important potential, we also provided some policy suggestions. [Copyright &y& Elsevier]
- Published
- 2014
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8. A Study of Electrical Aging of the Turn-to-Turn Oil-Paper Insulation in Transformers with a Step-Stress Method
- Author
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Qingguo Chen, Yonghong Wang, Xinlao Wei, and Hongyan Nie
- Subjects
Control and Optimization ,Materials science ,Threshold limit value ,020209 energy ,step stress ,Energy Engineering and Power Technology ,Mechanical engineering ,Field strength ,02 engineering and technology ,electrical aging ,lcsh:Technology ,01 natural sciences ,law.invention ,Operating temperature ,law ,Electric field ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,Transformer ,Engineering (miscellaneous) ,010302 applied physics ,lcsh:T ,Renewable Energy, Sustainability and the Environment ,Estimation theory ,oil-immersed paper turn-to-turn insulation ,transformer ,parameter estimation ,Electromagnetic coil ,Energy (miscellaneous) ,Voltage - Abstract
This study investigates the electrical aging characteristics of oil-paper composite insulation. In this paper, a coils model and test system for oil-paper transformer insulation are designed. The electrical aging tests of the model coils at room temperature and operating temperature are performed using the step-stress method. A new method for estimating the unknown parameters in the inverse power exponent model is proposed, and the inverse power model life formula expressed by voltage and electric field strength is obtained. Considering the electrical aging process at the operating temperature, the allowable field strength of the inter-turn insulation of oil-immersed transformers can be improved. The new parameter estimation method proposed in this paper can be used to calculate the unknown parameters of the step-stress solid insulation aging model. This method has a clear physical meaning and can be solved easily. When the stressed voltage is below a certain threshold value, the life of the transformer coil turn-to-turn insulation grease oiled paper model is longer at operating temperatures compared with that at room temperature; when the voltage is higher than the threshold, it presents the opposite tendency.
- Published
- 2018
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9. Replicating Sachs and Warner’s Working Papers on the Resource Curse.
- Author
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Davis, Graham A.
- Subjects
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ECONOMIC development research , *WORKING papers , *DATA libraries , *ESTIMATION theory , *PUBLISHED errata - Abstract
This article reports on my attempt to replicate Sachs and Warner’s 1995 and 1997 resource curse working papers. The 1995 paper is not replicable for lack of a data archive. Pure replication of the 1997 paper is achieved. Statistical replication determines that the proposed institutional causes of the resource curse are not robust to country sample. Scientific replication shows that findings of a resource curse are not sensitive to different measures of resource intensiveness, though they are sensitive to estimation technique. Typographical errors in the published paper reveal the value of researchers making both their data and code available. [ABSTRACT FROM PUBLISHER]
- Published
- 2013
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10. Studying the loss of life of natural-ester-filled transformer insulation: impact of moisture on the aging rate of paper.
- Author
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Garcia, Belen, Garcia, Tamara, Primo, Victor, Burgos, Juan Carlos, and Urquiza, Domingo
- Subjects
ELECTRIC transformers ,ELECTRIC insulators & insulation ,MINERAL oils ,TRANSESTERIFICATION ,ESTIMATION theory - Abstract
Moisture is one of the most harmful agents for transformer solid insulation. The catalyzing effect of moisture on the degradation process of paper and pressboard has been studied by several authors, who developed models which they used to estimate how the aging process would be accelerated in the presence of water [1]?[5]. In [2] and [3] Lelekakis et al. reported the results of an experimental study in which samples with different moisture contents were aged in the presence of mineral oil (MO). In [3] an equation to determine the reduction of service lifetime of insulation subjected to increased temperature and with increased moisture content is proposed. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
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11. New Equivalent Circuit of Oil-Paper Insulation and Its Parameters Identification
- Author
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Ruliang Wang and Dehua He
- Subjects
Computer science ,Estimation theory ,Particle swarm optimization ,Hardware_PERFORMANCEANDRELIABILITY ,Function (mathematics) ,symbols.namesake ,Control theory ,Insulation system ,Hardware_INTEGRATEDCIRCUITS ,symbols ,Equivalent circuit ,Computational problem ,Polarization (electrochemistry) ,Hardware_LOGICDESIGN ,Debye - Abstract
In order to finding more perfect dielectric response function, the mixed polarization equivalent circuit model is proposed by combining interface polarization equivalent circuit model in oil paper insulation, which fit the actual relaxation process of oil paper insulation system. At the same time, to resolve complex computational problems of parameters identification quickly, the method of parameters identification for mixed polarization circuit model is presented based on particle swarm optimization algorithm. Finally, through the analysis and comparison of examples, confirmed that the mixed polarization circuit model is correct and has higher accuracy compared to the Debye equivalent circuit model, and can more truly reflect the relaxation process of oil paper insulation system.
- Published
- 2020
12. Desert island papers-A life in variance parameter and quantitative genetic parameter estimation reviewed using 16 papers
- Author
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Robin Thompson
- Subjects
0301 basic medicine ,Mixed model ,Restricted maximum likelihood ,Scientific career ,03 medical and health sciences ,Food Animals ,Statistics ,Computer software ,Animals ,Humans ,Inbreeding ,Mathematics ,Estimation ,Likelihood Functions ,Sheep ,Models, Genetic ,Estimation theory ,0402 animal and dairy science ,04 agricultural and veterinary sciences ,General Medicine ,Variance (accounting) ,History, 20th Century ,040201 dairy & animal science ,030104 developmental biology ,Genetics, Population ,Linear Models ,Animal Science and Zoology ,Periodicals as Topic ,Algorithms ,Software - Abstract
I review my scientific career in terms of eight areas and 16 papers. The first two areas are associated with childhood. The other six are associated with residual maximum likelihood (REML), canonical transformation, inbreeding in selected populations, average information residual maximum likelihood (AIREML), the computer program ASReml and sampling-based estimation.
- Published
- 2018
13. On the robustness of dirty paper coding
- Author
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Uri Erez and Anatoly Khina
- Subjects
Engineering ,Estimation theory ,business.industry ,Transmitter ,Topology ,Upper and lower bounds ,Robustness (computer science) ,Channel state information ,Electronic engineering ,Dirty paper coding ,Electrical and Electronic Engineering ,business ,Scaling ,Computer Science::Information Theory ,Coding (social sciences) - Abstract
A dirty-paper channel is considered, where the transmitter knows the interference sequence up to a constant multiplicative factor, known only to the receiver. Lower bounds on the achievable rate of communication are derived by proposing a coding scheme that partially compensates for the imprecise channel knowledge.We focus on a communication scenario where the signal-to-noise ratio is high. Our approach is based on analyzing the performance achievable using lattice-based coding schemes. When the power of the interference is finite, we show that the achievable rate of this lattice-based coding scheme may be improved by a judicious choice of the scaling parameter at the receiver. We further show that the communication rate may be improved, for finite as well as infinite interference power, by allowing randomized scaling at the transmitter.
- Published
- 2010
14. A two-phase parameter estimation method for radiative transfer problems in paper industry applications
- Author
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Per Edström
- Subjects
Scattering ,Estimation theory ,Applied Mathematics ,media_common.quotation_subject ,Mathematical analysis ,General Engineering ,Phase (waves) ,Inverse problem ,Pulp and paper industry ,Asymmetry ,Computer Science Applications ,Convergence (routing) ,Radiative transfer ,Point (geometry) ,media_common ,Mathematics - Abstract
A two-phase method for estimation of the scattering and absorption coefficients and the asymmetry factor (σ s , σ a and g) in the radiative transfer problem is presented. The first phase parameterizes σ s and σ a through g via a simplified model and performs–at a relatively low cost–a scalar optimization over g. It is shown that this gives such a good starting point that the second phase can be accurately performed by a simple Gauss-Newton method. It is also shown that as a part of the first phase can be used on its own when only σ s and σ a are wanted, and it is noted that this gives higher accuracy than the commonly used Kubelka–Munk method when using standardized paper industry reflectance factor measurements. The parameter estimation problem is shown to be non-trivial and ill-conditioned, and its character is analysed. It is discussed that as standard optimization methods are so sensitive to the choice of starting point for this problem that it is hard to find a starting point that gives convergence a...
- Published
- 2008
15. Numerical estimation of the effective electrical conductivity in carbon paper diffusion media
- Author
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Zamel, Nada, Li, Xianguo, and Shen, Jun
- Subjects
- *
NUMERICAL analysis , *ESTIMATION theory , *ELECTRIC conductivity , *CARBON paper , *DIFFUSION , *ELECTRONS , *PROTON exchange membrane fuel cells , *ANISOTROPY , *ELECTRICAL resistivity - Abstract
Abstract: The transport of electrons through the gas diffusion layer (GDL) of polymer electrolyte membrane (PEM) fuel cells has a significant impact on the optimal design and operation of PEM fuel cells and is directly affected by the anisotropic nature of the carbon paper material. In this study, a three-dimensional reconstruction of the GDL is used to numerically estimate the directional dependent effective electrical conductivity of the layer for various porosity values. The distribution of the fibers in the through-plane direction results in high electrical resistivity; hence, decreasing the overall effective electrical conductivity in this direction. This finding is in agreement with measured experimental data. Further, using the numerical results of this study, two mathematical expressions were proposed for the calculation of the effective electrical conductivity of the carbon paper GDL. Finally, the tortuosity factor was evaluated as 1.7 and 3.4 in the in- and through-plane directions, respectively. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
16. Application and roll-out of infinite horizon MPC employing a nonlinear mechanistic model to paper machines
- Author
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Tor Anders Hauge, Bernt Lie, and Roger Slora
- Subjects
Production line ,Engineering ,business.product_category ,business.industry ,Estimation theory ,Process (computing) ,Kalman filter ,Industrial and Manufacturing Engineering ,Computer Science Applications ,Nonlinear system ,Paper machine ,Control and Systems Engineering ,Control theory ,Linearization ,Modeling and Simulation ,business - Abstract
A mechanistic nonlinear model of the wet end of paper machine 6 (PM6) at Norske Skog Saugbrugs, Norway has been developed, and used in an industrial MPC implementation. The MPC uses an infinite horizon criterion, successive linearization of the model, and estimation of states and parameters by an augmented Kalman filter. Variation in important quality variables and consistencies in the wet end have been reduced substantially, compared to the variation prior to the MPC implementation. The MPC also provides better efficiency through faster grade changes, control during sheet breaks and start ups, and better control during periods of poor measurements. From May 2002 of the MPC has been the preferred controller choice for the process operators at PM6. In this paper we also study if the model can be applied to PM4 at Norske Skog Saugbrugs, and PM3 at Norske Skog Skogn, Norway. No structural changes were necessary in order to fit the model to PM4 and PM3 data. The time spent on fitting the PM6 model to PM4 and PM3 is approximately 1% of the time spent on developing the original model. This should be a strong incentive for focusing on mechanistic modeling in industries were there are many similar production lines or units.
- Published
- 2005
17. Estimation of paper-moisture in transformer insulation employing dielectric spectroscopy data.
- Author
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Kumar, Alok, Verma, Hari Charan, Baral, Arijit, Pradhan, Arpan Kumar, and Chakravorti, Sivaji
- Subjects
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ESTIMATION theory , *MOISTURE measurement , *BROADBAND dielectric spectroscopy , *TRANSFORMER insulation , *POLARIZATION (Electricity) - Abstract
Accurate estimation of paper-moisture in transformer insulation is necessary for ensuring their satisfactory operation. Paper-moisture in transformer insulation can be estimated from their corresponding transfer function zero obtained from insulation model that is parameterised using polarisation depolarisation current data. However, paper-moisture estimated using transfer function zero is less reliable for a new unit. Considering the fact, a method is proposed in this work that can estimate the paper-moisture with greater accuracy. Instead of using only transfer function zero, tand has also been employed for estimating the paper-moisture. In order to investigate the effectiveness, the proposed technique has first been applied on several test samples in the laboratory. The proposed technique is then applied on few power transformers to estimate their paper-moisture. Results obtained from the experiment show that this technique can estimate the paper-moisture content within test samples and power transformer insulation with better accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
18. Estimating psychological networks and their accuracy: A tutorial paper.
- Author
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Epskamp, Sacha, Borsboom, Denny, and Fried, Eiko I.
- Subjects
- *
PSYCHOLOGICAL databases , *STATISTICAL accuracy , *PSYCHOMETRICS , *PSYCHOLOGICAL research -- Methodology , *STATISTICAL bootstrapping , *ESTIMATION theory - Abstract
The usage of
psychological networks that conceptualize behavior as a complex interplay of psychological and other components has gained increasing popularity in various research fields. While prior publications have tackled the topics of estimating and interpreting such networks, little work has been conducted to check howaccurate (i.e., prone to sampling variation) networks are estimated, and howstable (i.e., interpretation remains similar with less observations) inferences from the network structure (such as centrality indices) are. In this tutorial paper, we aim to introduce the reader to this field and tackle the problem of accuracy under sampling variation. We first introduce the current state-of-the-art of network estimation. Second, we provide a rationale why researchers should investigate the accuracy of psychological networks. Third, we describe how bootstrap routines can be used to (A) assess the accuracy of estimated network connections, (B) investigate the stability of centrality indices, and (C) test whether network connections and centrality estimates for different variables differ from each other. We introduce two novel statistical methods: for (B) thecorrelation stability coefficient , and for (C) thebootstrapped difference test for edge-weights and centrality indices. We conducted and present simulation studies to assess the performance of both methods. Finally, we developed the free R-packagebootnet that allows for estimating psychological networks in a generalized framework in addition to the proposed bootstrap methods. We showcasebootnet in a tutorial, accompanied by R syntax, in which we analyze a dataset of 359 women with posttraumatic stress disorder available online. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
19. Weighted Stochastic Gradient Identification Algorithms for ARX models** This paper was supported by Specialized Research Fund for the Doctoral Program of Higher Education under Grant No. 20132302110053
- Author
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Ai-Guo Wu, Rui-Qi Dong, and Fang-Zhou Fu
- Subjects
Identification (information) ,Current (mathematics) ,Control and Systems Engineering ,Estimation theory ,Convergence (routing) ,Algorithm ,Mathematics ,Weighting ,Term (time) - Abstract
In this paper, weighted stochastic gradient (WSG) algorithms for ARX models are proposed by modifying the standard stochastic gradient identification algorithms. In the proposed algorithms, the correction term is a weighted term of the correction terms of the standard SG algorithm in the current and last recursive steps. In addition, a latest estimation based WSG (LE-WSG) algorithm is also established. The convergence performance of the proposed LE-WSG algorithm is then analyzed. It is shown by a numerical example that both the WSG and LE-WSG algorithms can possess faster convergence speed and higher convergence precision compared with the standard SG algorithms if the weighting factor is appropriately chosen.
- Published
- 2015
20. Estimation of moisture variations on paper machines
- Author
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Guy A. Dumont, M.S. Davies, Claes Lindeborg, E.M. Heaven, F.T. Ordubadi, I.M. Jonsson, Yifeng Fu, and K. Natarajan
- Subjects
Engineering ,Moisture ,business.industry ,Noise (signal processing) ,Estimation theory ,Process (computing) ,Value (computer science) ,Kalman filter ,Identifier ,Control and Systems Engineering ,Control theory ,Paper machine control ,Electrical and Electronic Engineering ,business - Abstract
An improved estimation algorithm for use in processing data generated online by a scanning sensor is described. The algorithm is to be used as part of a paper machine control system to maintain the moisture content of the sheet at a target value. The algorithm makes use of a previously published model to rapidly estimate, in the presence of noise, cross-direction and machine-direction (CD and MD) moisture profiles. The basic algorithm consists of a modified least-squares (LS) parameter identifier for estimating CD profile deviations and a Kalman filter for estimating MD disturbances. Simulation results showing the effectiveness of the algorithm in estimating known profiles are given. Results of the offline application of the algorithm to industrial data are also given. Online tests have been performed to demonstrate the improvements in accuracy and speed of detection of process upsets. The algorithm can be extended to other measurement models. >
- Published
- 1993
21. Estimating effective thermal conductivity in carbon paper diffusion media
- Author
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Zamel, Nada, Li, Xianguo, Shen, Jun, Becker, Jürgen, and Wiegmann, Andreas
- Subjects
- *
THERMAL conductivity , *COMMERCIALIZATION , *PROTON exchange membrane fuel cells , *HEAT transfer , *DIFFUSION , *ESTIMATION theory , *INTEGRATED software , *POROUS materials - Abstract
Abstract: Heat management is crucial to polymer electrolyte membrane (PEM) fuel cell commercialization. Numerical modeling is often used to simulate heat transfer in the various components of the cell and specifically the gas diffusion layer (GDL). Due to the porous nature of the gas diffusion layer and its complexity of anisotropy, the effect of the structure on the thermal conductivity is usually taken into account by introducing an effective thermal conductivity. In this study, the effective thermal conductivity of carbon paper diffusion media was estimated numerically. Carbon paper is often used as the GDL in PEM fuel cells due to its ability to efficiently transport electrons, heat and gaseous species. Using the GeoDict code, a realistic three-dimensional pore morphology of carbon paper was used as the modeling domain and the governing mathematical equations were solved using the commercial software package Fluent (6.3.26) and the ThermoDict solver. The geometrical effects on the effective thermal conductivity were investigated for different geometries. It was found that the effective thermal conductivity is highly sensitive to the geometry of the porous material under investigation. The effective thermal conductivity is much larger in the in-plane direction when compared with the value in the through-plane direction. Further, the change of the effective thermal conductivity due to porosity and compression was studied. Finally, correlations for the through-plane and in-plane effective thermal conductivity were developed. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
22. Sensorless tension control in paper machines
- Author
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J.M. Bentley, M.A. Valenzuela, and Robert D. Lorenz
- Subjects
Engineering ,Electronic speed control ,Signal processing ,business.product_category ,business.industry ,Estimation theory ,Control engineering ,Swing ,Load cell ,Industrial and Manufacturing Engineering ,Paper machine ,Control and Systems Engineering ,Control theory ,Control system ,Electrical and Electronic Engineering ,business ,Machine control - Abstract
Proper operation of the dry end of a paper machine requires some type of sheet tension control. Present systems use either indirect-speed-control-based schemes, or sensor-based direct tension control utilizing load cells or swing rolls. The indirect schemes are inadequate for most newer machines, and both types of the commonly used sensor-based schemes are invasive, expensive, require either special, or extra rolls, and add complexity to the sheet runs. This paper proposes and evaluates sheet tension estimation using only conventional motor and control signals, present in all newer drive controllers, integrated into a process model observer. This observer-based approach eliminates the need for the invasive tension transducers, and may also be used to replace the inaccurate indirect speed control schemes.
- Published
- 2003
23. Exports and growth: a causality analysis for the pulp and paper industries based on international panel data.
- Author
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Chao, W. S. and Buongiorno, J.
- Subjects
EXPORTS ,INDUSTRIAL laws & legislation ,EXPORT brokers ,PAPER industry ,INTERNATIONAL trade ,ESTIMATION theory ,MATHEMATICAL statistics ,STOCHASTIC processes - Abstract
This study examines the causal relations between exports and domestic production in the pulp and paper industries. The issue is whether exports are the engine of growth, or whether exports follow growth. The data were time-series of the 15 main exporting countries between 1961 and 1995. The method was Granger-causality analysis with error correction, based on models estimated in three ways: ordinary least squares by country, least squares with dummy variables (LSDV), and seemingly unrelated regression. Regardless of method, the strongest relation was an instantaneous (within a year) feedback between exports and production. The LSDV results implied average multipliers across countries of 1.2 to 1.4 from exports to production, and 0.20 to 0.25 from production to exports, in both industries. Experiments with monthly data on the pulp industries of Canada and the USA showed that temporal aggregation could affect the Granger-causality test results. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
24. Applications of system identification to paper machine model development and controller design
- Author
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I.M. Jonsson, E.M. Heaven, R.N. Vyse, K. M. Vu, M.A. Manness, and T.M. Kean
- Subjects
Identification (information) ,Engineering ,Paper machine ,business.product_category ,Data collection ,Estimation theory ,business.industry ,Multivariable calculus ,System identification ,Process (computing) ,Process control ,Control engineering ,business - Abstract
The evolution of the computer-based data collection and analysis systems has lead to significant advancements in the application of modern system identification techniques to paper machine model development. Process data obtained from paper machines excited with pseudo-random binary sequences (PRBS) can be used to determine process dynamics, isolate multivariable process interactions and develop advanced computer models to evaluate existing and new control strategies. This paper examines some of the traditional parametric identification techniques such as least squares, maximum likelihood or instrumental variable methods applied to data collected from a paper machine. The resulting paper machine model includes the process dynamics, the shape of the responses in a cross machine direction sense and defines the interactions between the machine direction and cross machine direction control elements. Finally, the paper illustrates the application of the models to minimum variance methods of coordinating multiple actuators to reduce overall finished paper variability. >
- Published
- 2002
25. Measure of nonlinearity for underwater target tracking using hull-mounted sensor
- Author
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Omkar Lakshmi Jagan, B. and Koteswara Rao, S.
- Published
- 2022
- Full Text
- View/download PDF
26. Discussion of the paper ‘A general framework for functional regression modelling’.
- Author
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Bai, Jiawei, Ivanescu, Andrada, and Crainiceanu, Ciprian M.
- Subjects
- *
REGRESSION analysis , *DATA analysis , *MATHEMATICS theorems , *COEFFICIENTS (Statistics) , *ESTIMATION theory - Abstract
This discussion provides our reaction to the article by Greven and Scheipl. It contains an overview of their article and a description of the many areas of research that remain open and could benefit from further methodological and computational development. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
27. Optimal dynamic experiment design for guaranteed parameter estimation**Acknowledgement: The research leading to these results has received funding from the European Commission under grant agreement number 291458 (MOBOCON). We are grateful to the anonymous reviewer for comments that helped improving the quality of the paper
- Author
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Anwesh Reddy Gottu Mukkula and Radoslav Paulen
- Subjects
education.field_of_study ,Mathematical optimization ,021103 operations research ,Estimation theory ,Design of experiments ,Population ,0211 other engineering and technologies ,02 engineering and technology ,Expected value ,Bilevel optimization ,Set (abstract data type) ,020401 chemical engineering ,Quantitative Biology::Populations and Evolution ,A priori and a posteriori ,0204 chemical engineering ,education ,Confidence region ,Mathematics - Abstract
This paper presents an approach for the design of dynamic experiments in the framework of bounded-error (guaranteed) parameter estimation that determines the confidence region of model parameters similarly to a posteriori analysis done in least-squares estimation. As in the classical approach to design of experiments, an essential part of the solution procedure is to approximate the resulting joint-confidence region. In this contribution, we develop the procedure to over-approximate the parameter set resulting from guaranteed parameter estimation based on the expected values of parameters. Subsequently, we pose the problem for design of experiments as a bilevel program, which is regularized in order to be well-posed. We demonstrate our approach on the Lotka-Volterra (predator-prey) model, modified to control the population of prey.
- Published
- 2016
28. Re-Evaluating Machine Learning for MRP Given the Comparable Performance of (Deep) Hierarchical Models.
- Author
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GOPLERUD, MAX
- Subjects
MACHINE learning ,MULTILEVEL models ,POLITICAL science ,SPLINES ,ESTIMATION theory - Abstract
Multilevel regression and post-stratification (MRP) is a popular use of hierarchical models in political science. Multiple papers have suggested that relying on machine learning methods can provide substantially better performance than traditional approaches that use hierarchical models. However, these comparisons are often unfair to traditional techniques as they omit possibly important interactions or nonlinear effects. I show that complex ("deep") hierarchical models that include interactions can nearly match or outperform state-of-the-art machine learning methods. Combining multiple models into an ensemble can improve performance, although deep hierarchical models are themselves given considerable weight in these ensembles. The main limitation to using deep hierarchical models is speed. This paper derives new techniques to further accelerate estimation using variational approximations. I provide software that uses weakly informative priors and can estimate nonlinear effects using splines. This allows flexible and complex hierarchical models to be fit as quickly as many comparable machine learning techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Cross-directional Estimation and Predictive Control of Paper Machines Using DWT
- Author
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Yiming Lou, Zhihuan Song, and Ping Li
- Subjects
Model predictive control ,Basis (linear algebra) ,Control theory ,Estimation theory ,General Chemical Engineering ,Model prediction ,Component (UML) ,Wavelet transform ,Geology ,Algorithm ,Mathematics ,Domain (software engineering) - Abstract
This paper proposes a novel approach for cross-directional (CD) estimation, modeling and control on paper machines based on discrete wavelet transforms (DWT). The CD basis weight variations are approximated at various resolutions using wavelet multiresolution analysis (WMRA). The controllable component of CD variations can be extracted from the original samples by choosing a suitable threshold resolution. An acceptable response model describing the relationship between the settings of the slice-screws to the basis weight profile is obtained. The controller synthesis, model prediction, optimization and parameter estimation are all performed in the DWT domain. The size of optimization and control problems associated with such large dimensions can be significantly reduced.
- Published
- 2008
30. Remarks on the paper by Sun and Meng, Appl. Math. Comput. 174 (2006).
- Author
-
Mařík, Robert
- Subjects
- *
LINEAR differential equations , *ESTIMATION theory , *MATHEMATICAL proofs , *MATHEMATICAL functions , *ARBITRARY constants - Abstract
In the paper the second order half-linear delay differential equation ( r ( t ) | u ′ ( t ) | α - 1 u ′ ( t ) ) ′ + p ( t ) | u ( τ ( t ) ) | α - 1 u ( τ ( t ) ) = 0 , α > 1 is studied under the condition ∫ ∞ r - 1 / α ( t ) d t < ∞ . The oscillation criterion proved by Sun and Meng (2006, Theorem 2.2) is carefully examined and improved by simplifying and sharpening the estimates used in the original proof and removing unnecessary assumptions. Among others, using elementary arguments we show that an arbitrary positive nondecreasing function ρ from this criterion can be safely and with no loss of generality replaced by a constant function. An extension to other related equations, such as neutral equations is also provided. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
31. Robust Sheet Tension Estimation for Paper Winders
- Author
-
M. Anibal Valenzuela, Daniel Sbarbaro, and Rodrigo Carrasco
- Subjects
Engineering ,Tension (physics) ,business.industry ,Estimation theory ,Continuous monitoring ,Industrial and Manufacturing Engineering ,Acceleration ,Control and Systems Engineering ,Robustness (computer science) ,Control theory ,Calibration ,Torque ,Electrical and Electronic Engineering ,Robust control ,business - Abstract
This paper proposes and evaluates two robust sheet tension estimation algorithms based on unwind and rewind variables, respectively. The proper sheet tension estimation is guaranteed by a continuous monitoring of the differences between the actual estimated values and the values predicted from the last calibration of the estimation parameters. The evaluation was performed with the aid of a developed winder emulator that allowed the off-line testing in a real-time field environment, including the inertial setting of the estimation constants, and evaluation of both 4 and 6 shipping-roll cycles. The sheet tension estimation results confirm the precise and stable operation of the proposed robust estimation algorithms, in estimation tests conducted with signals from a winder model, and with tests involving actual field signals from an operational winder.
- Published
- 2008
32. Paper Parameter Estimation Using Terahertz Time-Domain Spectroscopy
- Author
-
Frank M. Haran, Stephane Savard, J. Steven Dodge, Payam Mousavi, David R. Jez, and Ian Bushfield
- Subjects
Materials science ,Optics ,Basis (linear algebra) ,Terahertz radiation ,business.industry ,Estimation theory ,Monte Carlo method ,Terahertz time-domain spectroscopy ,business ,Spectroscopy ,Sample (graphics) ,Computational physics ,Terahertz spectroscopy and technology - Abstract
We demonstrate a terahertz time-domain technique for measuring thickness, moisture and basis weight of paper. We validate our technique for a sample compressed to different thicknesses and establish uncertainty limits using Monte Carlo simulations.
- Published
- 2014
33. Two-Way Writing on Dirty Paper
- Author
-
Mohammad Rostami and R. Khosravi-Farsani
- Subjects
Channel code ,Computer science ,Estimation theory ,business.industry ,Gaussian ,Markov process ,Noise (electronics) ,Computer Science Applications ,symbols.namesake ,Interference (communication) ,Channel state information ,Modeling and Simulation ,symbols ,Electrical and Electronic Engineering ,Telecommunications ,business ,Algorithm ,Decoding methods ,Computer Science::Information Theory ,Communication channel - Abstract
In this paper, the Two-Way Channel (TWC) with noncausal Channel State Information (CSI) is investigated. For the discrete memoryless channel an achievable rate region is derived. Then by extending the result to the Gaussian TWC with additive interference noise, it is shown that the capacity region of the latter channel is the same as the capacity when there is no interference, i.e., a two-way version of Costa's writing on dirty paper problem is established.
- Published
- 2011
34. Paper Parameter Estimation Using Time-domain Terahertz Spectroscopy
- Author
-
Payam Mousavi, Stephane Savard, Ian Bushfield, David R. Jez, J. Steven Dodge, and Frank M. Haran
- Subjects
Materials science ,Optics ,Basis (linear algebra) ,Estimation theory ,business.industry ,business ,Time domain terahertz spectroscopy ,Terahertz spectroscopy and technology - Abstract
We demonstrate a technique for determining the thickness, moisture, and basis weight of paper, using time-domain terahertz spectroscopy. The fundamental uncertainty limits on all three paper processing parameters are competitive with existing sensor technology. Article not available.
- Published
- 2014
35. A model-based approach to quality control of paper production.
- Author
-
Brown, Patrick E., Diggle, Peter J., and Henderson, Robin
- Subjects
QUALITY control ,PAPER mills ,STOCHASTIC processes ,ESTIMATION theory ,MATHEMATICAL models ,STATE-space methods - Abstract
This paper uses estimated model parameters as inputs into multivariate quality control charts. The thickness of paper leaving a paper mill is measured at a high sampling rate, and these data are grouped into successive data segments. A stochastic model for paper is fitted to each data segment, leading to parameter estimates and information-based standard errors for these estimates. The estimated model parameters vary by more than one can be explained by the information-based standard errors, suggesting that the ‘true’ underlying parameters are not constant over time. A model is formulated for the true parameters in which the information matrix dictates the distribution for the observed parameters given the true parameters. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
36. Outliers and Model Selection: Discussion of the Paper by Søren Johansen and Bent Nielsen.
- Author
-
Doornik, Jurgen A. and Hendry, David F.
- Subjects
- *
OUTLIER detection , *RANKING (Statistics) , *ROBUST statistics , *ESTIMATION theory , *MATHEMATICAL variables - Abstract
It is argued that model selection and robust estimation should be handled jointly. Impulse indicator saturation makes that possible, but leads to the situation where there are more variables than observations. This is illustrated by revisiting the analysis of Tobin's food data. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
37. A Non-Gaussian Spatial Process Model for Opacity of Flocculated Paper
- Author
-
Patrick Brown, Robin Henderson, and Peter J. Diggle
- Subjects
Statistics and Probability ,Opacity ,Stochastic process ,Stochastic modelling ,Estimation theory ,Gaussian ,Covariance ,symbols.namesake ,Frequency domain ,Statistics ,symbols ,Statistical physics ,Statistics, Probability and Uncertainty ,Gaussian process ,Mathematics - Abstract
Product quality in the paper-making industry can be assessed by opacity of a linear trace through continuous production sheets, summarized in spectral form. We adopt a class of non-Gaussian stochastic models for continuous spatial variation to describe data of this type. The model has flexible covariance structure, physically interpretable parameters and allows several scales of variation for the underlying process. We derive the spectral properties of the model, and develop methods of parameter estimation based on maximum likelihood in the frequency domain. The methods are illustrated using sample data from a UK mill.
- Published
- 2003
38. Modeling the polarization spectrum in composite oil/paper insulation systems
- Author
-
Patrícia Romeiro da Silva Jota, Syed Islam, and F.G. Jota
- Subjects
Moisture ,law ,Computer science ,Estimation theory ,Electronic engineering ,Dissipation factor ,Equivalent circuit ,Dielectric ,Electrical and Electronic Engineering ,Low frequency ,Transformer ,Voltage ,law.invention - Abstract
The determination of the polarization spectrum in the low frequency region of the dissipation factor, commonly has been used in practice to diagnose insulation conditions. The recovery voltage method (RVM) is one of the methods used to estimate the polarization spectrum. Nevertheless, current analysis of the RVM tests do not use all the information available from the test. In this paper, a mathematical model of the polarization spectrum is proposed. It is shown that, from the derived model, some of the hidden RVM peaks can be identified. Since the difficulty to derive a model from RVM data increases with the number of the peaks to be identified, a simpler model is always preferable. A scheme for determining the parameters of an equivalent circuit is also given, The composite oil/paper insulation is considered which is extensively used in cables and transformers. Cellulose paper, such as the Manila-Kraft type, which is used as insulation, exerts a major influence on the life of the equipment because of its hygroscopic nature. The importance of detecting and eliminating moisture from paper is crucial in oil-impregnated HV insulation. Analysis of the polarization spectrum has been used by several utilities to determine moisture in the paper. Recently, some test results indicated that the polarization spectrum may not clearly show important peaks corresponding to local moisture ingress and thus can mislead experts in the field, The developed model has been validated using RVM data of real power transformers.
- Published
- 1999
39. On the Robustness of Dirty Paper Coding.
- Author
-
Khina, Anatoly and Erez, Uri
- Subjects
- *
TRANSMITTERS (Communication) , *CODING theory , *ESTIMATION theory , *ERROR , *LATTICE theory , *FINITE integration technique - Abstract
A dirty-paper channel is considered, where the transmitter knows the interference sequence up to a constant multiplicative factor, known only to the receiver. Lower bounds on the achievable rate of communication are derived by proposing a coding scheme that partially compensates for the imprecise channel knowledge. We focus on a communication scenario where the signal-to-noise ratio is high. Our approach is based on analyzing the performance achievable using lattice-based coding schemes. When the power of the interference is finite, we show that the achievable rate of this lattice-based coding scheme may be improved by a judicious choice of the scaling parameter at the receiver. We further show that the communication rate may be improved, for finite as well as infinite interference power, by allowing randomized scaling at the transmitter. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
40. Differences in the Visual Design Language of Paper-and-Pencil Surveys Versus Web Surveys: A Field Experimental Study on the Length of Response Fields in Open-Ended Frequency Questions.
- Author
-
Fuchs, Marek
- Subjects
- *
SURVEYS , *RESPONDENTS , *QUESTIONNAIRES , *ESTIMATION theory , *ESTIMATES , *BIO-bibliography , *LITERATURE , *OPEN-ended questions - Abstract
Respondents in self-administered, paper-based surveys answer open-ended frequency questions differently depending on the size of the response field provided. Longer fields increase the proportion of alphanumeric elaborations or answers explicitly designated as an estimate ("about 20," "60-70"). By contrast, shorter fields yield higher proportions of pure digit responses. It is assumed that respondents interpret the size of the response field as an instruction regarding the format of the expected answer. In this article, the authors assess the effect of the length of the response field in a web survey compared to a paper-and-pencil questionnaire. Results indicate that the effect of the length of the response field is more pronounced in the paper-and-pencil condition compared to the web survey condition. This raises the question as to what extent the underlying visual design language differs across self-administered survey modes. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
41. A New Method for the Identification of Hammerstein Model**This paper was not presented at any IFAC meeting. This paper was recommended for publication in revised form by Associate Editor B.W. Bequette under the direction of Editor Yaman Arkun
- Author
-
M. Nazmul Karim and Hussain N. Al-Duwaish
- Subjects
Engineering ,Artificial neural network ,Estimation theory ,business.industry ,Computer Science::Neural and Evolutionary Computation ,System identification ,Nonlinear system ,Control and Systems Engineering ,Control theory ,Convergence (routing) ,Feedforward neural network ,Autoregressive–moving-average model ,Electrical and Electronic Engineering ,Time series ,business - Abstract
A new method for the identification of the nonlinear Hammerstein model, consisting of a static nonlinear part in cascade with a linear dynamic part, is introduced. The static nonlinear part is modeled by a multilayer feedforward neural network (MFNN), and the linear part is modeled by an autoregressive moving average (ARMA) model. A recursive algorithm is developed for estimating the weights of the MFNN and the parameters of ARMA model. Simulation examples are included to illustrate the performance of the proposed method. © 1997 Elsevier Science Ltd.
- Published
- 1997
42. Subspace Algorithms for the Identification of Multivariable Dynamic Errors-in-Variables Models**This paper was not presented at any IFAC meeting. This paper was recommended for publication in revised form by Associate Editor H. Hjalmarsson under the direction of Editor Torsten Söderström
- Author
-
Chun Tung Chou and Michel Verhaegen
- Subjects
Frequency response ,Noise ,Signal-to-noise ratio ,Control and Systems Engineering ,Control theory ,Estimation theory ,System identification ,Errors-in-variables models ,White noise ,Electrical and Electronic Engineering ,Subspace topology ,Mathematics - Abstract
We consider the problem of identifying multivariable finite dimensional linear time-invariant systems from noisy input/output measurements. Apart from the fact that both the measured input and output are corrupted by additive white noise, the output may also be contaminated by a term which is caused by a white input process noise; furthermore, all these noise processes are allowed to be correlated with each other. We shall develop a solution to this problem in the framework of subspace identification and we shall show that our algorithms give consistent estimates when the system is operating in open- or closed-loop. Two realistic simulation studies are presented to demonstrate the practical applicability of the proposed algorithms. © 1997 Elsevier Science Ltd.
- Published
- 1997
43. Effort Estimation in Agile Software Development: An Updated Review.
- Author
-
Dantas, Emanuel, Perkusich, Mirko, Dilorenzo, Ednaldo, Santos, Danilo F. S., Almeida, Hyggo, and Perkusich, Angelo
- Subjects
AGILE software development ,COMPUTER software ,ESTIMATION theory ,ARTIFICIAL intelligence ,MACHINE learning - Abstract
One of the main issues of an agile software project is how to accurately estimate development effort. In 2014, a Systematic Literature Review (SLR) regarding this subject was published. The authors concluded that there were several gaps in the literature, such as the low level of accuracy of the techniques and little consensus on appropriate cost drivers. The goal of our work is to provide an updated review of the state of the art based on this reference SLR work. We applied a Forward Snowballing approach, in which our seed set included the former SLR and its selected papers. We identified a strong indication of solutions based on Artificial Intelligence and Machine Learning methods for effort estimation in Agile Software Development (ASD). We also identified that there is a gap in terms of agreement on suitable cost drivers. Thus, we applied Thematic Analysis in the selected papers and identified a representative set of 10 cost drivers for effort estimation. This updated review of the state of the art resulted in 24 new relevant papers selected. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
44. Determination of calcium carbonate and styrene-butadiene latex content in the coating layer of coated paper.
- Author
-
Zhao, Huan, Hou, Qingxi, Hong, Yimei, Liu, Wei, Li, Yang, and Tong, Fang
- Subjects
CALCIUM carbonate ,STYRENE ,SURFACE coatings ,INFRARED radiation ,REGRESSION analysis ,ESTIMATION theory - Abstract
Abstract: The surface infrared spectra of coated paper with different levels of calcium carbonate and SB-latex in the coating layer were measured using ATR-FTIR. The relations between different levels of CaCO
3 and SB-latex and their respective characteristic peak areas were then established. The results show that the general regression neural network (GRNN) model can be used to estimate the CaCO3 and SB-latex contents in coatings of coated papers. The maximum errors for calcium carbonate and SB-latex were only 3.32% and 3.39%, respectively, and occurred under conditions that are at the extreme of what might be encountered in an actual production facility. [Copyright &y& Elsevier]- Published
- 2014
- Full Text
- View/download PDF
45. Estimation in paper machine control
- Author
-
Guy A. Dumont, M.S. Davies, and X.G. Wang
- Subjects
Engineering ,Stationary process ,Basis (linear algebra) ,Estimation theory ,business.industry ,Explained sum of squares ,Kalman filter ,Residual ,Extended Kalman filter ,Control and Systems Engineering ,Control theory ,Modeling and Simulation ,Autoregressive–moving-average model ,Electrical and Electronic Engineering ,business ,Algorithm - Abstract
The problem of online estimation of basis weight and moisture content in paper machines is discussed, and algorithms for separating cross machine and machine direction (MD) variations using scanned data are proposed. Because of its inherent nonlinearity, the moisture scheme uses a bootstrap algorithm, assuming known MD dynamics. For basis weight, the model linearity can be used to develop an extended Kalman filter to estimate the more complicated MD dynamics. Both algorithms have been tested on industrial data. Results from the basis-weight algorithm when applied to industrial scanned and stationary data collected from an operating paper machine show that a second order autoregressive moving average (ARMA) model gives the best fit to the data in terms of sum of squares of prediction errors and in terms of the whiteness of the residual. Furthermore, there is a very good agreement between the MD models estimated with the scanned data and the single point data. >
- Published
- 1993
46. Preface to the papers on 'Small area estimation'.
- Author
-
Tzavidis, Nikos, Zhang, Li‐Chun, Pfeffermann, Danny, and Lahiri, Partha
- Subjects
ESTIMATION theory ,TIME series analysis ,MEASUREMENT errors - Abstract
An introduction to papers on small area estimation featured in the current issue is presented, with topics including poverty mapping, time series models and measurement error models.
- Published
- 2017
- Full Text
- View/download PDF
47. Robust Sheet Tension Estimation for Paper Winders.
- Author
-
Valenzuela, M. Aníbal, Carrasco, Rodrigo, and Sbarbaro, Daniel
- Subjects
- *
ROBUST control , *ESTIMATION theory , *WINDING machines , *ALGORITHMS , *ELECTRIC windings , *DETECTORS - Abstract
This paper proposes and evaluates two robust sheet tension estimation algorithms based on unwind and rewind variables, respectively. The proper sheet tension estimation is guaranteed by a continuous monitoring of the differences between the actual estimated values and the values predicted from the last calibration of the estimation parameters. The evaluation was performed with the aid of a developed winder emulator that allowed the offline testing in a real-time field environment, including the initial setting of the estimation constants, and evaluation of both four- and six-shipping-roll cycles. The sheet tension estimation results confirm the precise and stable operation of the proposed robust estimation algorithms, in tests conducted with signals from a winder model, and with tests involving actual field signals from an operational winder. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
48. Analysis of Using Machine Learning Techniques for Estimating Solar Panel Performance in Edge Sensor Devices.
- Author
-
Dobrilovic, Dalibor, Pekez, Jasmina, Ognjenovic, Visnja, and Desnica, Eleonora
- Subjects
SOLAR panels ,ESTIMATION theory ,WIRELESS sensor nodes ,RENEWABLE energy sources ,MACHINE learning ,ENERGY harvesting ,SOLAR energy ,SOLAR power plants - Abstract
Featured Application: This paper presents a methodology for the implementation of edge intelligence for predicting solar panel performances on wireless sensor nodes. The importance of the usage of renewable energy sources in powering wireless sensor nodes in IoT and sensor networks grows together with the increasing number of utilized sensor nodes. Considering the other types of renewable energy sources, solar power differs as the most suitable one and emerges as the major source for powering sensor nodes. Thus, the consideration of using sensor nodes and collected sensor data for estimating solar panel performances and therefore solar power potential can improve the efforts in this direction. This paper presents the methodology for implementing edge intelligence on wireless sensor nodes for solar panel output voltage estimation and forecasting. The methodology covers the usage of the Python Scikit-learn package and micromlgen library for the implementation of edge intelligence on Arduino clone-based sensor nodes, particularly the development boards based on the ESP8266 chips. Scikit-learn is used for analyzing the efficiency of various regressors on collected solar data. The micromlgen library is then used for implementing those regressors on Arduino and clone nodes. The prediction of solar panel voltage generation is based on a single-sensor reading—UV or BH1750 light sensor. The Random Forest and Decision Tree regressors are implemented on the ESP8266-based development board—Wemos D1 R2. The estimation accuracy of the RF model is an MSE of approximately 0.10, MAE of 0.07 for UV and 0.04 for BH1750, and an R
2 of approximately 0.93 for both UV and BH1750 light sensors. The Decision Tree model has a lower accuracy with an MSE between 0.13 and 0.14, MAE of 0.07 for UV and 0.04 for BH1750, and R2 of 0.90 and 0.89 for the UV and BH1750 sensors, respectively. The methodology and its efficiency are presented and discussed in this paper. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
49. An alternative rule for placement of empirical points on Weibull probability paper
- Author
-
Antoni Drapella and Sylwia Kosznik
- Subjects
Engineering ,Estimation theory ,business.industry ,Order statistic ,Monte Carlo method ,Estimator ,Management Science and Operations Research ,Expected value ,Shape parameter ,Transformation (function) ,Statistics ,Safety, Risk, Reliability and Quality ,business ,Weibull distribution - Abstract
This paper proposes an alternative rule for placing empirical points on Weibull probability paper. Following the standard or old rule, one takes the mean or median value of the order statistics first, then performs the Weibull transformation. The new rule is to make the Weibull transformation first, then take the expected value of the transformed order statistics. Although the new rule for placing points requires much more complicated calculations, a simple Monte Carlo experiment shows that the new rule estimator of the shape parameter is unbiased, whereas the old rule estimator turns out to be heavily biased.
- Published
- 1999
50. Paper Parameter Estimation Using Time-Domain Terahertz Spectroscopy
- Author
-
Ian Bushfield, J. Steven Dodge, Frank M. Haran, Payam Mousavi, and Stephane Savard
- Subjects
Materials science ,Basis (linear algebra) ,Terahertz radiation ,business.industry ,Estimation theory ,Optical instrument ,Monte Carlo method ,Sample (graphics) ,Computational physics ,law.invention ,Terahertz spectroscopy and technology ,symbols.namesake ,Optics ,law ,symbols ,Rayleigh scattering ,business - Abstract
We demonstrate a time-domain terahertz technique for measuring thickness, moisture and basis weight of paper. We validate our technique for a sample compressed to different thicknesses and establish uncertainty limits using Monte Carlo simulations.
- Published
- 2012
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