Articles de revues : « Processes and schemes »

1

Seleznev, I. V., E. V. Konopatskiy et O. S. Voronova. « VARIATIVE GEOMETRIC ALGORITHMS FOR MODELING MULTIFACTOR PROCESSES ». Construction and industrial safety, n^o 21 (73) (2021) : 135–45. http://dx.doi.org/10.37279/2413-1873-2021-21-135-145.

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The work is investigated by the influence of variable geometric algorithms in modeling multifactor processes using multidimensional interpolation. Geometric models of multifactorial processes obtained using multidimensional interpolation inherent variability, which is a consequence of the multiplicity of the choice of reference lines during the development of geometric modeling schemes. At the same time, all possible variations of geometric interpolyns are fully satisfying the initial data. It has been established that the number of variations of geometric schemes directly depends on the number of current parameters and the dimension of the space in which the simulated geometrical object is located. Thus, a variable approach to geometrical modeling of multifactor processes generates a number of scientific tasks, the main one is the need to determine the effect of the variability of geometric algorithms on the final results of the computational experiment and, as a result, the choice of the best modeling results. To this end, the article presents the studies of variable geometric algorithms and computational experiments on the example of 2-parametric geometric interpolyns. A classification of 2-parametric geometric interpolytesses, which were conditionally divided into 3 types. Depending on the geometric scheme of constructing interpolynta, the square geometric scheme, a rectangular geometric scheme, a mixed geometric scheme. As a result of computational experiments, it was found that for a square geometric scheme, the variability does not affect the final results, in rectangular geometric schemes, the variability has a slight influence, and mixed geometric schemes may have significant differences and require additional research to select the highest quality geometric process model. Comparison of geometric models were performed by the methods of scientific visualization by overlaying the response surfaces on each other.

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Zhang, Guang J., et Xiaoliang Song. « Parameterization of Microphysical Processes in Convective Clouds in Global Climate Models ». Meteorological Monographs 56 (1 avril 2016) : 12.1–12.18. http://dx.doi.org/10.1175/amsmonographs-d-15-0015.1.

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Abstract The microphysical processes inside convective clouds play an important role in climate. They directly control the amount of detrainment of cloud hydrometeor and water vapor from updrafts. The detrained water substance in turn affects the anvil cloud formation, upper-tropospheric water vapor distribution, and thus the atmospheric radiation budget. In global climate models, convective parameterization schemes have not explicitly represented microphysics processes in updrafts until recently. In this paper, the authors provide a review of existing schemes for convective microphysics parameterization. These schemes are broadly divided into three groups: tuning-parameter-based schemes (simplest), single-moment schemes, and two-moment schemes (most comprehensive). Common weaknesses of the tuning-parameter-based and single-moment schemes are outlined. Examples are presented from one of the two-moment schemes to demonstrate the performance of the scheme in simulating the hydrometeor distribution in convection and its representation of the effect of aerosols on convection.

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Jin, Jiming, Norman L. Miller et Nicole Schlegel. « Sensitivity Study of Four Land Surface Schemes in the WRF Model ». Advances in Meteorology 2010 (2010) : 1–11. http://dx.doi.org/10.1155/2010/167436.

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The Weather Research and Forecasting (WRF) model version 3.0 developed by the National Center for Atmospheric Research (NCAR) includes three land surface schemes: the simple soil thermal diffusion (STD) scheme, the Noah scheme, and the Rapid Update Cycle (RUC) scheme. We have recently coupled the sophisticated NCAR Community Land Model version 3 (CLM3) into WRF to better characterize land surface processes. Among these four land surface schemes, the STD scheme is the simplest in both structure and process physics. The Noah and RUC schemes are at the intermediate level of complexity. CLM3 includes the most sophisticated snow, soil, and vegetation physics among these land surface schemes. WRF simulations with all four land surface schemes over the western United States (WUS) were carried out for the 1 October 1995 through 30 September 1996. The results show that land surface processes strongly affect temperature simulations over the (WUS). As compared to observations, WRF-CLM3 with the highest complexity level significantly improves temperature simulations, except for the wintertime maximum temperature. Precipitation is dramatically overestimated by WRF with all four land surface schemes over the (WUS) analyzed in this study and does not show a close relationship with land surface processes.

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Istigecheva, E. V., et T. E. Grigorieva. « LOGISTIC SCHEMES MODELLING IN BUSINESS PROCESSES ». Informatika i sistemy upravleniya, n^o 47 (2016) : 25–33. http://dx.doi.org/10.22250/isu.2016.47.25-33.

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Holst, Lars, et Jürg Hüsler. « Sequential urn schemes and birth processes ». Advances in Applied Probability 17, n^o 2 (juin 1985) : 257–79. http://dx.doi.org/10.2307/1427140.

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An urn contains balls of different colours, which are randomly drawn one at a time. After each draw the number of balls in the urn with the same colour as the ball last drawn is changed. Special cases are sampling with and without replacement, and Pólya sampling. The drawing stops when a given number of colours has been drawn a given number of times. The number of times the different colours have been drawn is studied in this paper by imbedding the urn scheme in birth processes. Both exact and asymptotic results are obtained. In particular, waiting times for sampling with and without replacement and for Pólya sampling are considered.

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Robert, Philippe, et Florian Simatos. « Occupancy schemes associated to Yule processes ». Advances in Applied Probability 41, n^o 2 (juin 2009) : 600–622. http://dx.doi.org/10.1239/aap/1246886625.

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An occupancy problem with an infinite number of bins and a random probability vector for the locations of the balls is considered. The respective sizes of the bins are related to the split times of a Yule process. The asymptotic behavior of the landscape of the first empty bins, i.e. the set of corresponding indices represented by point processes, is analyzed and convergences in distribution to mixed Poisson processes are established. Additionally, the influence of the random environment, the random probability vector, is analyzed. It is represented by two main components: an independent, identically distributed sequence and a fixed random variable. Each of these components has a specific impact on the qualitative behavior of the stochastic model. It is shown in particular that, for some values of the parameters, some rare events, which are identified, determine the asymptotic behavior of the average values of the number of empty bins in some regions.

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Robert, Philippe, et Florian Simatos. « Occupancy schemes associated to Yule processes ». Advances in Applied Probability 41, n^o 02 (juin 2009) : 600–622. http://dx.doi.org/10.1017/s0001867800003438.

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An occupancy problem with an infinite number of bins and a random probability vector for the locations of the balls is considered. The respective sizes of the bins are related to the split times of a Yule process. The asymptotic behavior of the landscape of the first empty bins, i.e. the set of corresponding indices represented by point processes, is analyzed and convergences in distribution to mixed Poisson processes are established. Additionally, the influence of the random environment, the random probability vector, is analyzed. It is represented by two main components: an independent, identically distributed sequence and a fixed random variable. Each of these components has a specific impact on the qualitative behavior of the stochastic model. It is shown in particular that, for some values of the parameters, some rare events, which are identified, determine the asymptotic behavior of the average values of the number of empty bins in some regions.

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Holst, Lars, et Jürg Hüsler. « Sequential urn schemes and birth processes ». Advances in Applied Probability 17, n^o 02 (juin 1985) : 257–79. http://dx.doi.org/10.1017/s0001867800014968.

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An urn contains balls of different colours, which are randomly drawn one at a time. After each draw the number of balls in the urn with the same colour as the ball last drawn is changed. Special cases are sampling with and without replacement, and Pólya sampling. The drawing stops when a given number of colours has been drawn a given number of times. The number of times the different colours have been drawn is studied in this paper by imbedding the urn scheme in birth processes. Both exact and asymptotic results are obtained. In particular, waiting times for sampling with and without replacement and for Pólya sampling are considered.

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9

Schmid, W. « CUSUM control schemes for Gaussian processes ». Statistical Papers 38, n^o 2 (juin 1997) : 191–217. http://dx.doi.org/10.1007/bf02925223.

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Epprecht, Eugenio Kahn, Laura França Marques Barbosa et Bruno Francisco Teixeira Simões. « SPC of multiple stream processes : a chart for enhanced detection of shifts in one stream ». Production 21, n^o 2 (29 avril 2011) : 242–53. http://dx.doi.org/10.1590/s0103-65132011005000022.

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The efficiency of Boyd's group charts -the classical scheme for the statistical control of multiple-stream processes- is impaired by its underlying model of the process not considering that part of the variation in such processes is common to all streams. Mortell and Runger (1995) and Runger, Alt and Montgomery (1996) proposed alternative schemes which take this fact into account. We propose a third scheme: a modified group chart, based on the differences between the values of the quality characteristic in each particular stream and the average of the values of all streams. The average run lengths of this scheme and of the competing schemes in the case of shifts in the mean of one individual stream are obtained either analytically or by simulation and compared. The results show the superiority of the proposed scheme except for shifts smaller than one standard deviation, against which no one of the schemes is really efficient.

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Bright, Belinda Sharon, et R. Swarnalatha. « Performance evaluation of two degree of freedom conventional controller adopting the smith principle for first order process with dead time ». International Journal of Electrical and Computer Engineering (IJECE) 9, n^o 4 (1 août 2019) : 3002. http://dx.doi.org/10.11591/ijece.v9i4.pp3002-3014.

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The Proportional Integral Derivative Controller is a typical controller implemented frequently in many services and integrating the Smith predictor is an extremely useful control system structure for processes with dead time. This paper has evaluated two control schemes with the modified structures of the Smith predictor incorporating dead time compensators and conventional controllers for first order process with dead time. The disturbance response and the set point response for both the control schemes were decoupled from each other. Therefore two degrees of freedom control design was formulated, and hence the responses could be designed separately. The two control schemes have mainly two variables to be adjusted that decide the robustness and closed-loop behaviour. This paper also contains the calculation of various parameters that were used in each scheme. A comparison of the two control schemes along with the general Smith predictor control scheme was made using Simulink/Matlab. The conclusion is the second control scheme gave better response overall for the processes with dead time having dead time uncertainty and for the processes with dead time without dead time uncertainty.

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Lee, Seoung Soo, Chang-Hoon Jung, Sen Chiao, Junshik Um, Yong-Sang Choi et Won Jun Choi. « Comparison of Simulations of Updraft Mass Fluxes and Their Response to Increasing Aerosol Concentration between a Bin Scheme and a Bulk Scheme in a Deep-Convective Cloud System ». Advances in Meteorology 2019 (12 juin 2019) : 1–29. http://dx.doi.org/10.1155/2019/9292535.

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Key microphysical processes whose parameterizations have substantial impacts on the simulation of updraft mass fluxes and their response to aerosol are investigated in this study. For this investigation, comparisons of these parameterizations are made between a bin scheme and a bulk scheme. These comparisons show that the differences in the prediction of cloud droplet number concentration (CDNC) between the two schemes determine whether aerosol-induced invigoration of updrafts or convection occurs. While the CDNC prediction leads to aerosol-induced invigoration of updrafts and an associated 20% increase in the peak value of the updraft-mass-flux vertical profile in the bin scheme, it leads to aerosol-induced suppression of updrafts and an associated 7% decrease in the peak value in the bulk scheme. The comparison also shows that the differences in ice processes, in particular, in the snow loading lead to the different vertical patterns of the updraft-mass-flux profile, which is represented by the peak value and its altitude, between the schemes. Higher loading of snow leads to around 20–30% higher mean peak value and its around 40% higher altitude in the bin scheme than in the bulk scheme. When differences in the CDNC prediction and ice processes are removed, differences in the invigoration and the vertical pattern disappear between the schemes. However, despite this removal, differences in the magnitude of updraft mass fluxes still remain between the schemes. Associated with this, the peak value is around 10% different between the schemes. Also, after the removal, there are differences in the magnitude between cases with different aerosol concentrations for each scheme. Associated with this, the peak value is also around 10% different between those cases for each scheme. The differences between the cases with different aerosol concentrations for each scheme are generated by different evaporative cooling and different intensity of gust fronts between those cases. The remaining differences between the schemes are generated by different treatments of collection and sedimentation processes.

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Grabowski, Wojciech W., Odile Thouron, Jean-Pierre Pinty et Jean-Louis Brenguier. « A Hybrid Bulk–Bin Approach to Model Warm-Rain Processes ». Journal of the Atmospheric Sciences 67, n^o 2 (1 février 2010) : 385–99. http://dx.doi.org/10.1175/2009jas3155.1.

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Abstract This paper presents a hybrid approach to model warm-rain processes, merging the diverse schemes of bulk and detailed (bin) microphysics. In the bulk scheme, the key assumption is that the exact saturation is maintained inside a cloud. In contrast, the supersaturation inside a cloud is predicted in the bin scheme and is applied to calculate the diffusional growth of cloud droplets. Predicting the supersaturation is numerically cumbersome, however, and typically requires spatial and temporal resolutions that are significantly higher than those that can be applied in the bulk scheme. At the same time, supersaturations inside clouds are small, and the condensate amounts in bulk and bin schemes differ insignificantly. This critical observation forms a starting point for the hybrid bulk–bin approach. In this approach, when the cloud water first appears, the activation scheme inserts cloud droplets at the low end of the bin representation. Subsequent diffusional and eventually accretional growth shift the spectrum toward larger sizes so that the saturation inside a cloud is maintained. Details of the hybrid approach are discussed in this paper, and the validation against the traditional bin scheme in a framework of the adiabatic rising parcel is presented. Before the scheme can be applied to the multidimensional cloud model, a 1D advection–condensation problem of Grabowski and Smolarkiewicz is used to address the issue of the numerical difficulties that finite-difference schemes experience near cloud edges. In the bulk case, these are in the form of condensation rate overshoots and undershoots; and this aspect requires special attention in the hybrid scheme. A novel approach is developed that provides a physically consistent solution near cloud edges using the hybrid bulk–bin scheme. The key is to allow grid boxes near the edges to be partly cloudy and to include spectral changes of cloud droplets that take this into account. Application of the hybrid scheme to an idealized 2D problem of moist thermal rising from rest and producing rain illustrates the application of the scheme to practical problems of cloud dynamics and warm-rain microphysics.

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Lin, Heng-Sheng, Chien-Yu Lee, Chia-Jung Lin et Ho-Chung Fu. « Evaluation of the sinking processes for high-pressure-gas cylinders ». MATEC Web of Conferences 185 (2018) : 00007. http://dx.doi.org/10.1051/matecconf/201818500007.

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High-pressure-gas cylinders are used in broad applications. Cracks on the open end would occur during the riveting stage. Such forming defects are caused by excessive hardening, although the open end has been annealed with induction heating prior to the sinking operation. Therefore, a proper design for the sinking dies is essential to the forming production of the HPG cylinders. In this paper, two die-design concepts were examined which included the conventional design for six-stage sinking with fixed die radius, and the economic design for five-stage sinking with incremental die radii. Finite element software DEFORM 2D was used to investigate the two sinking schemes. The effect of the sinking schemes on the sinking load, strain distribution, and lip thickness were analysed. The results show that the economic five-stage sinking with a large increment of die radii can provide less strain hardening as compared to other sinking schemes. Although the forming load level is acceptable and the change of lip thickness is insignificant, the production cost of the five-stage scheme is still high. A more economic measure by sinking with one-stage rotary swaging can provide an alternative scheme with advantages of simple die design and saving the lead for annealing.

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Testut, Laurent, Rachael Hurd, Richard Coleman, Frédérique Rémy et Benoît Legrésy. « Comparison between computed balance velocities and GPS measurements in the Lambert Glacier basin, East Antarctica ». Annals of Glaciology 37 (2003) : 337–43. http://dx.doi.org/10.3189/172756403781815672.

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AbstractComparisons between computed balance velocities, obtained from two different computing schemes, and global positioning system (GPS)-derived velocities were made in the Lambert Glacier basin region, East Antarctica. The two computing schemes used for the balance-velocity computations (a flowline (FL) scheme (Remy and Minster, 1993) and a finite-difference (BW) scheme (Budd and Warner, 1996; Fricker and others, 2000)) were first evaluated and compared. One of the key issues studied was the spatial resolution of the digital elevation model (DEM), representing the surface topography of the ice sheet, and the sensitivity of the balance velocities to the length of smoothing applied to the DEM. Comparison with the GPS velocities validated the two schemes to within 5–25% but showed the high sensitivity of the flowline method to the length scale of the smoothing. The finite-difference scheme was found to be robust to the chosen smoothing scale, but the balance-velocity values increased when a finer-resolution DEM was used. Both FL and BW computing schemes tended to overestimate the balance velocities in comparison with the GPS values; some of this discrepancy can be attributed to ice-sheet sliding.

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Kang, Jeongho, et Kwangsue Chung. « HTTP Adaptive Streaming Framework with Online Reinforcement Learning ». Applied Sciences 12, n^o 15 (24 juillet 2022) : 7423. http://dx.doi.org/10.3390/app12157423.

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Dynamic adaptive streaming over HTTP (DASH) is an effective method for improving video streaming’s quality of experience (QoE). However, the majority of existing schemes rely on heuristic algorithms, and the learning-based schemes that have recently emerged also have a problem in that their performance deteriorates in a specific environment. In this study, we propose an adaptive streaming scheme that applies online reinforcement learning. When QoE degradation is confirmed, the proposed scheme adapts to changes in the client’s environment by upgrading the ABR model while performing video streaming. In order to adapt the adaptive bitrate (ABR) model to a changing network environment while performing video streaming, the neural network model is trained with a state-of-the-art reinforcement learning algorithm. The proposed scheme’s performance was evaluated using simulation-based experiments under various network conditions. The experimental results confirmed that the proposed scheme performed better than the existing schemes.

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Regmi, Samundra, Ioannis K. Argyros, Santhosh George et Christopher I. Argyros. « Numerical Processes for Approximating Solutions of Nonlinear Equations ». Axioms 11, n^o 7 (24 juin 2022) : 307. http://dx.doi.org/10.3390/axioms11070307.

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In this article, we present generalized conditions of three-step iterative schemes for solving nonlinear equations. The convergence order is shown using Taylor series, but the existence of high-order derivatives is assumed. However, only the first derivative appears on these schemes. Therefore, the hypotheses limit the utilization of the schemes to operators that are at least nine times differentiable, although the schemes may converge. To the best of our knowledge, no semi-local convergence has been given in the setting of a Banach space. Our goal is to extend the applicability of these schemes in both the local and semi-local convergence cases. Moreover, we use our idea of recurrent functions and conditions only on the derivative or divided differences of order one that appear in these schemes. This idea can be applied to extend other high convergence multipoint and multistep schemes. Numerical applications where the convergence criteria are tested complement this article.

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English, J. M., O. B. Toon, M. J. Mills et F. Yu. « Microphysical simulations of new particle formation in the upper troposphere and lower stratosphere ». Atmospheric Chemistry and Physics 11, n^o 17 (9 septembre 2011) : 9303–22. http://dx.doi.org/10.5194/acp-11-9303-2011.

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Abstract. Using a three-dimensional general circulation model with sulfur chemistry and sectional aerosol microphysics (WACCM/CARMA), we studied aerosol formation and microphysics in the upper troposphere and lower stratosphere (UTLS) as well as the middle and upper stratosphere based on three nucleation schemes (two binary homogeneous schemes and an ion-mediated scheme related to one of the binary schemes). Simulations suggest that ion-mediated nucleation rates in the UTLS are 25 % higher than its related binary scheme, but that the rates predicted by the two binary schemes vary by two orders of magnitude. None of the nucleation schemes is superior at matching the limited observations available at the smallest sizes. However, it is found that coagulation, not nucleation, controls number concentration at sizes greater than approximately 10 nm. Therefore, based on this study, processes relevant to atmospheric chemistry and radiative forcing in the UTLS are not sensitive to the choice of nucleation schemes. The dominance of coagulation over other microphysical processes in the UTLS is consistent with other recent work using microphysical models. Simulations using all three nucleation schemes compare reasonably well to observations of size distributions, number concentration across latitude, and vertical profiles of particle mixing ratio in the UTLS. Interestingly, we find that we need to include Van der Waals forces in our coagulation scheme to match the UTLS aerosol concentrations. We conclude that this model can reasonably represent sulfate microphysical processes in the UTLS, and that the properties of particles at atmospherically relevant sizes appear to be insensitive to the details of the nucleation scheme. We also suggest that micrometeorites, which are not included in this model, dominate the aerosol properties in the upper stratosphere above about 30 km.

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Pau, L.-F. « Defence Schemes From Attacker's Own Reward Processes ». International Journal of Network Security & ; Its Applications 5, n^o 4 (31 juillet 2013) : 95–104. http://dx.doi.org/10.5121/ijnsa.2013.5407.

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Borkar, V. S. « Stability of annealing schemes and related processes ». Systems & ; Control Letters 41, n^o 5 (décembre 2000) : 325–31. http://dx.doi.org/10.1016/s0167-6911(00)00073-6.

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Li, Jian, Fugee Tsung et Changliang Zou. « Directional Control Schemes for Multivariate Categorical Processes ». Journal of Quality Technology 44, n^o 2 (avril 2012) : 136–54. http://dx.doi.org/10.1080/00224065.2012.11917889.

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Artur, V. B., Yu M. Ermol'ev et Yu M. Kaniovskii. « Adaptive growth processes modeled by URN schemes ». Cybernetics 23, n^o 6 (1988) : 779–89. http://dx.doi.org/10.1007/bf01070240.

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Seignourel, Paul. « Discrete schemes for processes in random media ». Probability Theory and Related Fields 118, n^o 3 (novembre 2000) : 293–322. http://dx.doi.org/10.1007/pl00008743.

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Chen, J. P., I.-C. Tsai et Y. C. Lin. « A statistical-numerical aerosol parameterization scheme ». Atmospheric Chemistry and Physics Discussions 13, n^o 5 (8 mai 2013) : 12033–87. http://dx.doi.org/10.5194/acpd-13-12033-2013.

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Abstract. A new modal aerosol parameterization scheme, Statistical-Numerical Aerosol Parameterization (SNAP), was developed for studying aerosol processes and aerosol-cloud interactions in regional or global models. SNAP applies statistical fitting on numerical results to generate accurate parameterization formulas without sacrificing details of the growth kernel. Processes considered in SNAP include fundamental aerosol processes, as well as processes related to aerosol-cloud interactions. Comparison of SNAP with numerical solutions, analytical solutions, and binned aerosol model simulations showed that the new method performs well, with accuracy higher than that of the high-order numerical quadrature technique, at much less computation time. The SNAP scheme has been implemented in regional air quality models, producing results very close to those using binned-size schemes or numerical quadrature schemes.

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Chen, J. P., I.-C. Tsai et Y. C. Lin. « A statistical–numerical aerosol parameterization scheme ». Atmospheric Chemistry and Physics 13, n^o 20 (30 octobre 2013) : 10483–504. http://dx.doi.org/10.5194/acp-13-10483-2013.

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Abstract. A new modal aerosol parameterization scheme, the statistical–numerical aerosol parameterization (SNAP), was developed for studying aerosol processes and aerosol–cloud interactions in regional or global models. SNAP applies statistical fitting on numerical results to generate accurate parameterization formulas without sacrificing details of the growth kernel. Processes considered in SNAP include fundamental aerosol processes as well as processes related to aerosol–cloud interactions. Comparison of SNAP with numerical solutions, analytical solutions, and binned aerosol model simulations showed that the new method performs well, with accuracy higher than that of the high-order numerical quadrature technique, and with much less computation time. The SNAP scheme has been implemented in regional air quality models, producing results very close to those using binned-size schemes or numerical quadrature schemes.

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Rout, Sarit Kumar, Vamsi Krishna Boyanagari, Saumya Ranjan Pani, Tushar Mokashi, Maulik Chokshi et Shridhar M. Kadam. « How does Context Influence Implementation Mechanism of Publicly Funded Health Insurance Schemes in Indian States ». Journal of Health Management 24, n^o 1 (mars 2022) : 118–31. http://dx.doi.org/10.1177/09720634221078702.

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Introduction: The success of any insurance scheme is contingent upon well-defined processes related to payment, referral, grievances and quality control mechanisms. Any deviation observed may result in unsatisfactory performance. This study attempts to examine various processes related to the implementation of Pradhan Mantri Jan Arogya Yojana (PMJAY) and a state-specific insurance scheme across three states of India. Objective: To describe the policies and process adapted by selected states in implementing a government-sponsored health insurance scheme. To examine the strategies that work effectively, how they operate and what contextual factors enable or disable the desired implementation mechanisms. Methodology: The three states of Karnataka, Chhattisgarh, and Odisha were selected to understand various processes related to the implementation of Publicly Funded Health Insurance Schemes (PFHIS) schemes in diverse settings. A realist evaluation framework was used to study the contexts and mechanisms and how this influences outcomes. Results: The three schemes differ in implementation modes and follow different strategies owing to the local contexts. Some mechanisms worked well in specific contexts, whereas similar things have hindered the process in other contexts. Conclusion: The evidence generated is helpful to strengthen implementation processes under PMJAY and allows learning from each other to increase uptake of the scheme.

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Zhao, Xingbing, Zhiwei Heng, Xingwen Jiang, Qidong Yang, Yubin Li, Yuanjian Yang et Zhiqiu Gao. « Evaluation of the Effect of Stability Schemes on the Simulation of Land Surface Processes at a Western Tibetan Site ». Land 10, n^o 3 (3 mars 2021) : 253. http://dx.doi.org/10.3390/land10030253.

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The surface fluxes calculated in land surface models (LSMs) are sensitive to the determination of the stability parameter. Further, calculation of the surface fluxes over the Tibetan Plateau (TP) is crucial in the simulation of regional and global weather and climate. In this study, we use 2-year micrometeorological data measured from Shiquanhe, located in the western TP, to evaluate the performance of the widely used Noah LSM with five stability parameterization schemes. Results show that all five stability parameterization schemes can generally reproduce the observations, but the scheme proposed by Li has the smallest bias. The reason is that Li’s scheme is more accurate under the unstable condition, and the surface layer at Shiquanhe is mostly unstable. Further, the four non-iterative schemes show an advantage in terms of their computational efficiency compared to the iterative scheme adopted by the Noah LSM.

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English, J. M., O. B. Toon, M. J. Mills et F. Yu. « Microphysical simulations of new particle formation in the upper troposphere and lower stratosphere ». Atmospheric Chemistry and Physics Discussions 11, n^o 4 (20 avril 2011) : 12441–86. http://dx.doi.org/10.5194/acpd-11-12441-2011.

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Abstract. Using a three-dimensional general circulation model with sulfur chemistry and sectional aerosol microphysics (WACCM/CARMA), we studied aerosol formation and microphysics in the tropical upper troposphere and lower stratosphere (UTLS) based on three nucleation schemes (two binary homogeneous schemes and an ion-mediated scheme). Simulations suggest that ion-mediated nucleation rates in the UTLS are 25% higher than binary rates, but that the rates predicted by the two binary schemes vary by two orders of magnitude. However, it is found that coagulation, not nucleation, controls number concentration at sizes greater than approximately 10 nm. Therefore, based on this study, atmospherically relevant processes in the UTLS are not sensitive to the choice of nucleation schemes. The dominance of coagulation over other microphysical processes is consistent with other recent work using microphysical models. Simulations using all three nucleation schemes compare reasonably well to observations of size distributions, number concentration across latitude, and vertical profiles of particle mixing ratio in the UTLS. Interestingly, we find we need to include Van der Waals forces in our coagulation scheme to match the UTLS aerosol concentrations. We conclude that this model can accurately represent sulfate microphysical processes in the UTLS, and that the properties of particles at atmospherically relevant sizes are not sensitive to the details of the nucleation scheme. We also suggest that micrometeorites, which are not included in this model, dominate the aerosol properties in the upper stratosphere above about 30 km.

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Lileika, Gytenis, et Vigirdas Mackevičius. « Second-Order Weak Approximations of CKLS and CEV Processes by Discrete Random Variables ». Mathematics 9, n^o 12 (9 juin 2021) : 1337. http://dx.doi.org/10.3390/math9121337.

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In this paper, we construct second-order weak split-step approximations of the CKLS and CEV processes that use generation of a three−valued random variable at each discretization step without switching to another scheme near zero, unlike other known schemes (Alfonsi, 2010; Mackevičius, 2011). To the best of our knowledge, no second-order weak approximations for the CKLS processes were constructed before. The accuracy of constructed approximations is illustrated by several simulation examples with comparison with schemes of Alfonsi in the particular case of the CIR process and our first-order approximations of the CKLS processes (Lileika– Mackevičius, 2020).

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Yin, Jinfang, Xudong Liang, Hong Wang et Haile Xue. « Representation of the autoconversion from cloud to rain using a weighted ensemble approach : a case study using WRF v4.1.3 ». Geoscientific Model Development 15, n^o 2 (27 janvier 2022) : 771–86. http://dx.doi.org/10.5194/gmd-15-771-2022.

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Abstract. Cloud and precipitation processes remain among the largest sources of uncertainties in weather and climate modelling, and considerable attention has been paid to improving the representation of the cloud and precipitation processes in numerical models in the last several decades. In this study, we develop a weighted ensemble (named EN) scheme by employing several widely used autoconversion (ATC) schemes to represent the ATC from cloud water to rainwater. One unique feature of the EN approach is that the ATC rate is a weighted mean value based on the calculations from several ATC schemes within a microphysics scheme with a negligible increase in computation cost. The EN scheme is compared with the several commonly used ATC schemes by performing real case simulations. In terms of accumulated rainfall and extreme hourly rainfall rate, the EN scheme provides better simulations than by using the single Berry–Reinhardt scheme, which was originally used in the Thompson scheme. It is worth emphasizing, in the present study, that we only pay attention to the ATC process from cloud water into rainwater with the purpose of improving the modelling of the extreme rainfall events over southern China. Actually, any (source and sink) term in a cloud microphysics scheme can be treated with the same approach. The ensemble method proposed herein appears to have important implications for developing cloud microphysics schemes in numerical models, especially for the models with variable grid resolution, which would be expected to improve the representation of cloud microphysical processes in the weather and climate models.

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Baumgartner, Manuel, Max Sagebaum, Nicolas R. Gauger, Peter Spichtinger et André Brinkmann. « Algorithmic differentiation for cloud schemes (IFS Cy43r3) using CoDiPack (v1.8.1) ». Geoscientific Model Development 12, n^o 12 (11 décembre 2019) : 5197–212. http://dx.doi.org/10.5194/gmd-12-5197-2019.

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Abstract. Numerical models in atmospheric sciences not only need to approximate the flow equations on a suitable computational grid, they also need to include subgrid effects of many non-resolved physical processes. Among others, the formation and evolution of cloud particles is an example of such subgrid processes. Moreover, to date there is no universal mathematical description of a cloud, hence many cloud schemes have been proposed and these schemes typically contain several uncertain parameters. In this study, we propose the use of algorithmic differentiation (AD) as a method to identify parameters within the cloud scheme, to which the output of the cloud scheme is most sensitive. We illustrate the methodology by analyzing a scheme for liquid clouds, incorporated into a parcel model framework. Since the occurrence of uncertain parameters is not limited to cloud schemes, the AD methodology may help to identify the most sensitive uncertain parameters in any subgrid scheme and therefore help limiting the application of uncertainty quantification to the most crucial parameters.

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Labriola, Jonathan, Nathan Snook, Youngsun Jung et Ming Xue. « Explicit Ensemble Prediction of Hail in 19 May 2013 Oklahoma City Thunderstorms and Analysis of Hail Growth Processes with Several Multimoment Microphysics Schemes ». Monthly Weather Review 147, n^o 4 (25 mars 2019) : 1193–213. http://dx.doi.org/10.1175/mwr-d-18-0266.1.

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Abstract Hail forecast evaluations provide important insight into microphysical treatment of rimed ice. In this study we evaluate explicit 0–90-min EnKF-based storm-scale (500-m horizontal grid spacing) hail forecasts for a severe weather event that occurred in Oklahoma on 19 May 2013. Forecast ensembles are run using three different bulk microphysics (MP) schemes: the Milbrandt–Yau double-moment scheme (MY2), the Milbrandt–Yau triple-moment scheme (MY3), and the NSSL variable density-rimed ice double-moment scheme (NSSL). Output from a hydrometeor classification algorithm is used to verify surface hail size forecasts. All three schemes produce forecasts that predict the coverage of severe surface hail with moderate to high skill, but exhibit less skill at predicting significant severe hail coverage. A microphysical budget analysis is conducted to better understand hail growth processes in all three schemes. The NSSL scheme uses two-variable density-rimed ice categories to create large hailstones from dense, wet growth graupel particles; however, it is noted the scheme underestimates the coverage of significant severe hail. Both the MY2 and MY3 schemes produce many small hailstones aloft from unrimed, frozen raindrops; in the melting layer, hailstones become much larger than observations because of the excessive accretion of water. The results of this work highlight the importance of using a MP scheme that realistically models microphysical processes.

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Prajapati, D. R., et Sukhraj Singh. « Modified chart with optimized ARLs in autocorrelated processes ». TQM Journal 27, n^o 5 (10 août 2015) : 633–47. http://dx.doi.org/10.1108/tqm-04-2013-0052.

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Purpose – The purpose of this paper is to counter autocorrelation by designing the chart, using warning limits. Various optimal schemes of modified chart are proposed for various sample sizes (n) at levels of correlation (Φ) of 0.00, 0.475 and 0.95. These optimal schemes of modified chart are compared with the double sampling (DS) chart, suggested by Costa and Claro (2008). Design/methodology/approach – The performance of the chart is measured in terms of the average run length (ARL) that is the average number of samples before getting an out-of-control signal. Ultimately, due to the effect of autocorrelation among the data, the performance of the chart is suspected. The ARLs at various sets of parameters of the chart are computed by simulation, using MATLAB. The suggested optimal schemes are simpler schemes with limited number of parameters and smaller sample size (n=4) and this simplicity makes them very helpful in quality control. Findings – The suggested optimal schemes of modified chart are compared with the DS chart, suggested by Costa and Claro (2008). It is concluded that the modified chart outperforms the DS chart at various levels of correlation (Φ) and shifts in the process mean. The simplicity in the design of modified chart, makes it versatile for many industries. Research limitations/implications – Both the schemes are optimized by assuming the normal distribution. But this assumption may also be relaxed to design theses schemes for autocorrelated data. The optimal schemes for chart can be developed for variable sample size and for variable sampling intervals. The optimal schemes can also be explored for cumulative sum and exponentially weighted moving average charts. Practical implications – The correlation among the process outputs of any industry can be find out and corresponding to that level of correlation the suggested control chart parameters can be applied. The understandable and robust design of modified chart makes it usable for industrial quality control. Social implications – The rejection level of products in the industries can be reduced by designing the better control chart schemes which will also reduce the loss to the society, as suggested by Taguchi (1985). Originality/value – Although it is the extension of previous work but it can be applied to various manufacturing industries as well as service industries, where the data are positively correlated and normally distributed.

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Boluh, Kateryna, et Natalija Shchestyuk. « Simulating Stochastic Diffusion Processes and Processes with “Market” Time ». Mohyla Mathematical Journal 3 (29 janvier 2021) : 25–30. http://dx.doi.org/10.18523/2617-70803202025-30.

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The paper focuses on modelling, simulation techniques and numerical methods concerned stochastic processes in subject such as financial mathematics and financial engineering. The main result of this work is simulation of a stochastic process with new market active time using Monte Carlo techniques.The processes with market time is a new vision of how stock price behavior can be modeled so that the nature of the process is more real. The iterative scheme for computer modelling of this process was proposed.It includes the modeling of diffusion processes with a given marginal inverse gamma distribution. Graphs of simulation of the Ornstein-Uhlenbeck random walk for different parameters, a simulation of the diffusion process with a gamma-inverse distribution and simulation of the process with market active time are presented.To simulate stochastic processes, an iterative scheme was used: xk+1 = xk + a(xk, tk) ∆t + b(xk, tk) √ (∆t) εk,, where εk each time a new generation with a normal random number distribution.Next, the tools of programming languages for generating random numbers (evenly distributed, normally distributed) are investigated. Simulation (simulation) of stochastic diffusion processes is carried out; calculation errors and acceleration of convergence are calculated, Euler and Milstein schemes. At the next stage, diffusion processes with a given distribution function, namely with an inverse gamma distribution, were modelled. The final stage was the modelling of stock prices with a new "market" time, the growth of which is a diffusion process with inverse gamma distribution. In the proposed iterative scheme of stock prices, we use the modelling of market time gains as diffusion processes with a given marginal gamma-inverse distribution.The errors of calculations are evaluated using the Milstein scheme. The programmed model can be used to predict future values of time series and for option pricing.

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Bishwal, Jaya P. N. « Parameter Estimation for SPDEs Driven by Cylindrical Stable Processes ». European Journal of Mathematical Analysis 3 (11 juillet 2022) : 4. http://dx.doi.org/10.28924/ada/ma.3.4.

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We consider infinite dimensional extension of affine models with heavy tails in finance. We study several estimators of the drift parameter in the stochastic partial differential equation driven by cylindrical stable processes. We consider several sampling schemes. We also consider random sampling scheme, e.g, when the solution process is observed at the arrival times of a Poisson process. We obtain the consistency and the asymptotic normality of the estimators.

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Căzănescu, Virgil Emil, et Gheorghe Ştefănescu. « Towards a New Algebraic Foundation of Flowchart Scheme Theory ». Fundamenta Informaticae 13, n^o 2 (1 avril 1990) : 171–210. http://dx.doi.org/10.3233/fi-1990-13204.

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We develope a formalism for the algebraic study of flowchart schemes and their behaviours, based on a new axiomatic looping operation, called feedback. This formalism is based on certain flownomial expressions. Such an expression is built up from two types of atomic schemes (i.e., elements in a double-ranked set X considered as unknown computation processes, and elements in a “theory” T considered as known computation processes) by using three operations: sum, composition, and feedback. Flownomial expressions are subject to certain rules of identification. The axiomatization of flowchart schemes is based on the fact that a flowchart scheme may be identified with a class of isomorphic flownomial expressions in normal form. The corresponding algebra for flowchart schemes is called biflow. This axiomatization is extended to certain types of behaviour. We present axiomatizations for accessible flowchart schemes, reduced flowchart schemes, minimal flowchart schemes with respect to the input behaviour, minimal flowchart schemes with respect to the input-output behaviour etc. Some results are new, others are simple translations in terms of feedback of previous results obtained by using Elgot’s iteration or Kleene’s repetition. The paper also contains some historical comments.

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Venema, V., A. Schomburg, F. Ament et C. Simmer. « Two adaptive radiative transfer schemes for numerical weather prediction models ». Atmospheric Chemistry and Physics Discussions 7, n^o 3 (30 mai 2007) : 7235–75. http://dx.doi.org/10.5194/acpd-7-7235-2007.

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Abstract. Radiative transfer calculations in atmospheric models are computationally expensive, even if based on simplifications such as the δ-two-stream approximation. In most weather prediction models these parameterisation schemes are therefore called infrequently, accepting additional model error due to the persistence assumption between calls. This paper presents two so-called adaptive parameterisation schemes for radiative transfer in a limited area model: a perturbation scheme that exploits temporal correlations and a local-search scheme that mainly takes advantage of spatial correlations. Utilising these correlations and with similar computational resources, the schemes are able to predict the surface heating rates more accurately than a scheme based on the persistence assumption. An important property of these adaptive schemes is that their accuracy does not decrease much in case of strong reductions in the number of calls to the δ-two-stream scheme. It is hypothesised that the core idea can also be employed in parameterisation schemes for other processes and in other dynamical models.

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Venema, V., A. Schomburg, F. Ament et C. Simmer. « Two adaptive radiative transfer schemes for numerical weather prediction models ». Atmospheric Chemistry and Physics 7, n^o 21 (15 novembre 2007) : 5659–74. http://dx.doi.org/10.5194/acp-7-5659-2007.

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Abstract. Radiative transfer calculations in atmospheric models are computationally expensive, even if based on simplifications such as the δ-two-stream approximation. In most weather prediction models these parameterisation schemes are therefore called infrequently, accepting additional model error due to the persistence assumption between calls. This paper presents two so-called adaptive parameterisation schemes for radiative transfer in a limited area model: A perturbation scheme that exploits temporal correlations and a local-search scheme that mainly takes advantage of spatial correlations. Utilising these correlations and with similar computational resources, the schemes are able to predict the surface net radiative fluxes more accurately than a scheme based on the persistence assumption. An important property of these adaptive schemes is that their accuracy does not decrease much in case of strong reductions in the number of calls to the δ-two-stream scheme. It is hypothesised that the core idea can also be employed in parameterisation schemes for other processes and in other dynamical models.

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Chong, Zhi Lin, Shuo Huang, Amitava Mukherjee et Jun Yang. « Performance comparisons of distribution-free Shewhart-type Lepage and Cucconi schemes in monitoring complex process distributions ». Transactions of the Institute of Measurement and Control 42, n^o 14 (2 juillet 2020) : 2787–811. http://dx.doi.org/10.1177/0142331220932466.

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In recent years, researchers introduced several distribution-free schemes for simultaneously monitoring the location and scale parameters of distribution in the literature related to process monitoring and control. To this end, the Shewhart-Lepage (SL) and Shewhart-Cucconi (SC) schemes are two fundamental distribution-free schemes. These schemes are primarily designed to monitor the location-scale family of densities. In practice, apart from the location and scale parameters, we often encounter the presence of a shape (or skewness) parameter. In this article, we investigate the performance of the SL and SC schemes in monitoring such models. We consider some skewed distributions in the location-scale family with one or two additional parameters, some three-parameter time-to-event processes, such as three-parameter Weibull and Gamma, which are very common in various measurement and control literature. First, we present the in-control performance of the two competing schemes and then carry out a comprehensive out-of-control performance study by considering different combinations of shifts. Several recent investigations showed that the SC scheme performs just as well or better than the SL scheme in joint monitoring of the location and scale parameters for a large number of process distributions. The current study shows that in the presence of an additional parameter, especially when the shift in the shape parameter is substantial, the SL scheme is better; for a small change in shape, the SC scheme is more competitive. In general, the SL scheme performs better in monitoring the three-parameter distributions for time-to-event processes. Finally, a real application and some concluding remarks are presented.

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Kulava, L. D., N. N. Karpun, E. N. Zhuravleva et L. Ya Ayba. « Biological and economic efficiency of optimised pest control schemes for mandarin fruit in Abkhazian ». Horticulture and viticulture, n^o 5 (15 novembre 2021) : 36–43. http://dx.doi.org/10.31676/0235-2591-2021-5-36-43.

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Abkhazian mandarin crop is infected by over 50 pest species incurring marketable yield losses up to 83 %, which prioritises the development of new crop protection strategies that avoid organophosphorus compound usage leading to pest resistance. The studies were conducted during 2019–2020 in full-grown Citrus unshiu mandarin plantations at the Gulrypsh District of the Republic of Abkhazia adhering to the common protocol. Seven schemes were covered in study for the mandarin crop protection from rust mite Phyllocoptruta oleivora Ashmead and brown marble bug Halyomorpha halys Stål. Two schemes have been selected as optimised: scheme 5 (treatment 1 with Confidor Extra tank mix, 0.05 % WDG (imidacloprid) and 0.15 % Cytovit; treatment 2 with Vertimek tank mix, 0.1 % EC (abamectin, 18 g/L) and 0.15 % Cytovit; treatments 3--4 with Karate Zeon tank mix, 0.05 % OEC (lambda-cyhalothrin, 50 g/L) and 0.15 % Cytovit) and scheme 6 (treatment 1 with Metomax tank mix, 0.15 % SC (methomil 250 g/kg + bifenthrin 25 g/kg) and Vertimek, 0.1 % EC (abamectin, 18 g/L); treatments 2--3 with Karate Zeon, 0.05 % ISS (lambda-cyhalothrin, 50 g/L) and Vertimek, 0.1 % EC (abamectin, 18 g/L); treatment 4 with Karate Zeon, 0.05 % OEC (lambda-cyhalothrin, 50 g/L)). The schemes’ biological efficacy against mandarin pests was 80.0–84.2 and 81.3–87.7 %, providing for an average fruit weight improvement by 89.5 and 94.7 % vs. control, and 22.0 and 25.4 % vs. benchmark, respectively. Yield excess in the schemes was 85.7 and 91.7 % vs. control, and 36.8 and 41.3 % vs. economic cultivation, respectively. Class 1 fruits accounted for 63.3–65.6 % total harvest in schemes 5 and 6, whilst were not obtained in control.

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Bohaienko, Vsevolod A., Vladimir I. Kudin et Vasiliy V. Skopetsky. « Analysis of Computational Schemes for Geohydrodynamics Processes Modeling ». Journal of Automation and Information Sciences 41, n^o 8 (2009) : 1–12. http://dx.doi.org/10.1615/jautomatinfscien.v41.i8.10.

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Zenkin, O. V. « Some analogues between iterative processes and difference schemes ». Researches in Mathematics, n^o 2 (10 juillet 2021) : 16. http://dx.doi.org/10.15421/246905.

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BALDI, PAOLO, et CAMILLA PISANI. « SIMPLE SIMULATION SCHEMES FOR CIR AND WISHART PROCESSES ». International Journal of Theoretical and Applied Finance 16, n^o 08 (décembre 2013) : 1350045. http://dx.doi.org/10.1142/s0219024913500453.

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We develop some simple simulation algorithms for CIR and Wishart processes. We investigate rigorously the square of a matrix valued Ornstein–Uhlenbeck process, the main idea being to split the generator and to reduce the problem to the simulation of the square of a matrix valued Ornstein–Uhlenbeck process to be added to a deterministic process. In this way, we provide a weak second-order scheme that requires only the simulation of i.i.d. Gaussian r.v.'s and simple matrix manipulations.

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Briani, Maya, Roberto Natalini et Giovanni Russo. « Implicit–explicit numerical schemes for jump–diffusion processes ». Calcolo 44, n^o 1 (mars 2007) : 33–57. http://dx.doi.org/10.1007/s10092-007-0128-x.

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Naumov, Vitalii, Olha Shulika, Oleksandra Orda, Hanna Vasiutina, Marek Bauer et Myroslav Oliskevych. « Shaping the Optimal Technology for Servicing the Long-Distance Deliveries of Packaged Cargo by Road Transport ». Sustainability 14, n^o 12 (14 juin 2022) : 7283. http://dx.doi.org/10.3390/su14127283.

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The concept of sustainable transportation of goods as the primary paradigm for designing contemporary logistics systems assumes the use of energy-efficient and affordable modes of transport in a way that guarantees the most cost-efficient variant of the delivery scheme. That especially applies to road transport deliveries, where the number of alternatives for organizing the transportation process is numerous and the choice of the optimal solution is complicated by the multiple stochastic influences of the environment on the technological processes. In this paper, we contribute to solving the problem of shaping the sustainable delivery schemes by proposing an approach to shape the complete set of alternative transport and technological schemes for packaged cargo delivery by road transport. The developed mathematical model allows estimating the efficiency of each alternative delivery scheme for the given request and chooses the best variant that minimizes the total costs of all participants in the delivery process. The proposed algorithms are implemented in the C# programming language within the frame of a class library for modeling transport delivery processes. A case of transport processes for Delivery Ltd. (Kharkiv, Ukraine) is applied to illustrate the procedure of using the developed approach to choose the optimal transport and technological schemes for long-distance deliveries. As the result of simulating the goods transportation processes, we show the regression models that represent dependencies of the total costs for the implementation of a delivery scheme from the parameters of demand for the transportation of goods. These regression models allow estimating the most efficient delivery schemes based on the functional analysis of the obtained dependencies for the given demand parameters.

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Abdurashid, Altiev, Khalilova Barno et Avilova Nilufar. « Efficiency Of Use Of Schemes Of Regulation Of Land Use Processes In Uzbekistan ». American Journal of Interdisciplinary Innovations and Research 02, n^o 11 (30 novembre 2020) : 124–32. http://dx.doi.org/10.37547/tajiir/volume02issue11-22.

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The article presents the scientific and methodological basis of land use in the Republic of Uzbekistan. In particular, the differences and similarities between the definitions of "land use" by several scholars have been studied. The purpose and specific tasks of the land fund categories are described. The land-use system was critically analyzed and the inefficiency of land use categories of the Tashkent region, which is the object of research, was identified. Its causes have been investigated. In order to prevent these processes, the methodology of analysis and forecasting of these processes on the basis of cartographic and mathematical-cartographic methods was also analyzed. Suggestions are made for the development of land use forecasts based on some elements of the formation of land use schemes. In order to increase the efficiency of land use, it is necessary to clearly define the process of land use. A land-use scheme has been proposed to prevent identified deficiencies.

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Liu, Ming Jun, Zhen Yu Zhao et Bai Liu. « Process Optimization for the Side-Plate of the Core Part in Parallel Flow Evaporator ». Applied Mechanics and Materials 55-57 (mai 2011) : 961–65. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.961.

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The forming scheme of a side-plate of the core part in parallel flow evaporator was studied. Two forming schemes were compared and the explicit dynamic software DYNAFORM was applied to make simulations about the forming processes. According to comparisons between two forming schemes, the optimized scheme and process parameters were determined. Multi-station dies were designed based on the optimized process. Successful experiments with the dies showed that numerical simulation provided an efficient way for the optimization of the forming scheme in the side-plate production.

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Lee, Hyunho, et Jong-Jin Baik. « A Comparative Study of Bin and Bulk Cloud Microphysics Schemes in Simulating a Heavy Precipitation Case ». Atmosphere 9, n^o 12 (3 décembre 2018) : 475. http://dx.doi.org/10.3390/atmos9120475.

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Comparisons between bin and bulk cloud microphysics schemes are conducted by simulating a heavy precipitation case using a bin microphysics scheme and four double-moment bulk microphysics schemes in the Weather Research and Forecasting (WRF) model. For this, we implemented an updated bin microphysics scheme in the WRF model. All of the microphysics schemes underestimate observed strong precipitation, but the bin microphysics scheme yields the result that is closest to observations. The differences among the schemes are more pronounced in terms of hydrometeor number concentration than in terms of hydrometeor mixing ratio. In this case, the bin scheme exhibits remarkably more latent heat release by deposition and riming than the bulk schemes. This causes stronger updrafts and more upward transport of water vapor, which leads to more deposition, and again, increases the latent heat release. An additional simulation using the bin scheme but excluding the riming of cloud droplets on ice crystals, which is not or poorly treated in the examined bulk schemes, shows that surface precipitation is slightly weakened and moved farther downwind compared to that of the control simulation. This implies that the more appropriate representation of microphysical processes in the bin microphysics scheme contributes to the more accurate prediction of precipitation in this case.

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Matsubara, Atsushi, et Soichi Ibaraki. « Monitoring and Control of Cutting Forces in Machining Processes : A Review ». International Journal of Automation Technology 3, n^o 4 (5 juillet 2009) : 445–56. http://dx.doi.org/10.20965/ijat.2009.p0445.

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Much research has gone into machining process monitoring and control. This paper reviews monitoring and control schemes of cutting force and torque. Sensors to measure cutting force and torque, as well as their indirect estimation, are reviewed. Feedback control schemes and model-based feedforward scheduling schemes of cutting forces, as well as tool path optimization schemes for cutting force regulation, are reviewed. The authors’ works are also briefly presented.

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Luo, Qiming, Tinggui Zhang, Xiaofen Huang et Naihuan Jing. « Two Quantum Proxy Blind Signature Schemes Based on Controlled Quantum Teleportation ». Entropy 24, n^o 10 (5 octobre 2022) : 1421. http://dx.doi.org/10.3390/e24101421.

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We present a scheme for teleporting an unknown, two-particle entangled state with a message from a sender (Alice) to a receiver (Bob) via a six-particle entangled channel. We also present another scheme for teleporting an unknown one-particle entangled state with a message transmitted in a two-way form between the same sender and receiver via a five-qubit cluster state. One-way hash functions, Bell-state measurements, and unitary operations are adopted in these two schemes. Our schemes use the physical characteristics of quantum mechanics to implement delegation, signature, and verification processes. Moreover, a quantum key distribution protocol and a one-time pad are adopted in these schemes.

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