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Journal articles on the topic 'Model Order Formulation'
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Min Ma and R. Khazaka. "Model Order Reduction With Parametric Port Formulation." IEEE Transactions on Advanced Packaging 30, no. 4 (2007): 763–75. http://dx.doi.org/10.1109/tadvp.2007.908019.
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Pandey, Prateek, Anil Sharma, Hariom Sharma, Girish Kumar Vyas, and Manmohan Sharma. "Novel Researched Herbal Sunscreen Cream SPF Determination by In-Vitro Model." Asian Journal of Pharmaceutical Research and Development 11, no. 2 (2023): 83–90. http://dx.doi.org/10.22270/ajprd.v11i2.1246.
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INTRODUCTION: Researchers' interest in creating novel cosmetic formulations has increased due to consumer interest in herbal cosmetics and increased patent activity. The rights of indigenous traditional knowledge and benefit sharing are also safeguarded under IPR.
 OBJECTIVE: To formulate and evaluate herbal sunscreen with determination of Sun Protection Factor (SPF) and anti-oxidant activity. To compare Sun Protection Factor of developed formulation with marketed formulation.
 METHOD: The formulation was developed according to the prepared formula. And multiple tests were done for evaluation i.e., physical observation, spreadability, extrudability, occlusion study, stability study and SPF determination. All the evaluations were found satisfactory. Characterisation of SPF was calculated according to the and UV-Vis Spectrophotometer (LABMAN Scientific instruments Pvt. Ltd.).
 RESULTS:The synergistic activity of all herbal compounds utilized in herbal sunscreen formulations, such as Cucumis sativus, Solanum Lycopersicon, and Aloe barbadensis Efficacy of photoprotection found in following order Marketed formulation > F3 > F2 > F1. For prepared formulation F3 provided better results in comparison to Formulation1 and Formulation 2. Formulation 3 was compared with marketed preparation and it showed good SPF value nearer to market preparation. Overall results were satisfactory. These results reveal that the prepared F3 herbal sunscreen have good SPF and good sun protection activity.
 CONCLUSION: Formulation 3, which consists of three formulations, has been found to be effective as sunscreen in every way. Since few people use sunscreen, there is a need to raise public knowledge of the risks associated with sun exposure as well as the advantages of using sun protection products on a regular basis to lessen these effects. This kind of research will be useful in offering consumers with an all-inclusive solution or product that will protect them from the damaging effects of sunlight.
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Alotta, Gioacchino, Mario Di Paola, and Francesco Paolo Pinnola. "An unified formulation of strong non-local elasticity with fractional order calculus." Meccanica 57, no. 4 (2021): 793–805. http://dx.doi.org/10.1007/s11012-021-01428-x.
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AbstractThe research of a formulation to model non-local interactions in the mechanical behavior of matter is currently an open problem. In this context, a strong non-local formulation based on fractional calculus is provided in this paper. This formulation is derived from an analogy with long-memory viscoelastic models. Specifically, the same kind of power-law time-dependent kernel used in Boltzmann integral of viscoelastic stress-strain relation is used as kernel in the Fredholm non-local relation. This non-local formulation leads to stress-strain relation based on the space Riesz integral and derivative of fractional order. For unbounded domain, proposed model can be defined in stress- and in strain-driven formulation and in both cases the stress–strain relation represent a strong non-local model. Also, the proposed strain driven and stress driven formulations defined in terms of Riesz operators are proved to be fully consistent each another. Moreover, the proposed model posses a mechanical meaning and for unbounded non-local rod is described and discussed in detail.
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De la Peña, Jose, Jose Sanchez, Roberto Diaz, and Manuel Martin. "PHYSICAL MODEL AND REVISION OF THEORETICAL RUNUP." Coastal Engineering Proceedings 1, no. 33 (2012): 22. http://dx.doi.org/10.9753/icce.v33.currents.22.
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Several formulations deduced from empirical studies are available for runup estimation. Scattering is high when applied to practical cases. Through a state of the art best formulations are chosen. This equations are also studied in a physical model carried out in the Laboratory for Maritime Experimentation of CEDEX with three beaches with slopes 1/20, 1/30 and 1/50 and with sand bed. The performance of each formulation is discussed. A new formulation is proposed in order to give more weight to the beach slope thus reducing scatter.
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Fortuna, L., A. Gallo, and G. Nunnari. "Remarks on the Formulation of Model Order Estimation." IFAC Proceedings Volumes 18, no. 5 (1985): 1695–99. http://dx.doi.org/10.1016/s1474-6670(17)60812-7.
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Jin, Wen-Long. "Nonstandard second-order formulation of the LWR model." Transportmetrica B: Transport Dynamics 7, no. 1 (2019): 1338–55. http://dx.doi.org/10.1080/21680566.2019.1617803.
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D. V. R. N., Bhikshapathi, and Muralichand G. "Development, Solubility Enhancement and Characterization of Nimodipine Solid Dispersions." International Journal of Pharmaceutical Sciences and Nanotechnology 11, no. 5 (2018): 4231–39. http://dx.doi.org/10.37285/ijpsn.2018.11.5.2.
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The main aim of this study was to formulate and characterize nimodipine solid dispersions using various novel polymers. Solid dispersions were prepared by solvent evaporation method in order to improve the solubility and overall bioavailability of nimodipine. Solubility and dissolution studies indicate that Kolliwax RH 40 is the most suitable polymer. The solubility studies was corresponded with dissolution data and the formulation SD15 was found to be having highest drug release of about 98.96 ± 5.15% in about 90 minutes. In vitro release data from several formulations containing Nimodipine was determined kinetically using different mathematical models like Zero order, First order, Higuchi, and Korsmeyer–Peppas model. XRD and SEM studies indicate no crystallinity in the optimized formulation SD15. FTIR studies suggested good drug excipient compatibility between all components of prepared formulation. These results confirm the viability of enhancing the solubility of nimodipine by formulating the drug as solid dispersions in Kolliwax.
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Jafari, Hossein, and Ali Mazloumzadeh. "Presenting a new SJB model in order to formulate and select strategic goals in the strategic management process." International Journal of Innovation in Engineering 1, no. 2 (2021): 84–98. https://doi.org/10.52547/ijie.1.2.84.
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Today, the development of appropriate strategies as one of the basic tools of companies to compete in the markets of the e-commerce era. The strategy formulation process is inelastic with common strategic management models such as balanced scorecard and SWOT model in the face of market changes and competitive behaviour of competitors. It becomes. In this article, after reviewing the general structure of strategy formulation using the balanced scorecard model, the mentioned shortcomings in the strategy formulation process are examined. In the field of purposeful design, competitive strategies are presented and finally, the use of Judo Strategy model, SWOT matrix and Balanced Scorecard model of SJB framework is presented as an agile and systematic model in the process of designing and formulating strategy. In order to evaluate the applicability of this model, the beta company has been selected and with the cooperation of the top managers of that company, the proposed model has been implemented in the process of designing and formulating its strategy.
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Krupa, Pablo, Daniel Limon, Alberto Bemporad, and Teodoro Alamo. "Efficiently Solving the Harmonic Model Predictive Control Formulation." IEEE Transactions on Automatic Control 68, no. 9 (2023): 5568–75. https://doi.org/10.1109/TAC.2022.3220555.
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Harmonic model predictive control (HMPC) is a model predictive control (MPC) formulation that displays several benefits over other MPC formulations, especially when using a small prediction horizon. These benefits, however, come at the expense of an optimization problem that is no longer the typical quadratic programming problem derived from most linear MPC formulations due to the inclusion of a particular class of second-order cone constraints. This article presents a method for efficiently dealing with these constraints in operator splitting methods, leading to a computation time for solving HMPC in line with state-of-the-art solvers for linear MPC. We show how to apply this result to the alternating direction method of the multipliers algorithm, presenting a solver that we compare against other solvers from the literature, including solvers for other linear MPC formulations. The results show that the proposed solver, and by extension the HMPC formulation, is suitable for its implementation in embedded systems.
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da Silva Furlan, Laison Junio, Matheus Tozo de Araujo, Analice Costacurta Brandi, Daniel Onofre de Almeida Cruz, and Leandro Franco de Souza. "Different Formulations to Solve the Giesekus Model for Flow between Two Parallel Plates." Applied Sciences 11, no. 21 (2021): 10115. http://dx.doi.org/10.3390/app112110115.
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This work presents different formulations to obtain the solution for the Giesekus constitutive model for a flow between two parallel plates. The first one is the formulation based on work by Schleiniger, G; Weinacht, R.J., [Journal of Non-Newtonian Fluid Mechanics, 40, 79–102 (1991)]. The second formulation is based on the concept of changing the independent variable to obtain the solution of the fluid flow components in terms of this variable. This change allows the flow components to be obtained analytically, with the exception of the velocity profile, which is obtained using a high-order numerical integration method. The last formulation is based on the numerical simulation of the governing equations using high-order approximations. The results show that each formulation presented has advantages and disadvantages, and it was investigated different viscoelastic fluid flows by varying the dimensionless parameters, considering purely polymeric fluid flow, closer to purely polymeric fluid flow, solvent contribution on the mixture of fluid, and high Weissenberg numbers.
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Vaquero, Álvaro F., and Juan Córcoles. "Convex Formulations for Antenna Array Pattern Optimization Through Linear, Quadratic, and Second-Order Cone Programming." Mathematics 13, no. 11 (2025): 1796. https://doi.org/10.3390/math13111796.
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This work presents a comprehensive study on formulations for the radiation pattern design of antenna arrays through convex optimization techniques, with a focus on linear, quadratic, and second-order cone programming. The proposed approaches heavily rely on the construction of Hermitian forms to systematically build convex optimization problems for synthesizing desired beam patterns while including practical constraints such as sidelobe levels (SLLs), maximum directivity, and null placement. By formulating the radiation pattern synthesis problem through a convex formulation, global optimality and computational efficiency are ensured. The paper introduces the mathematical foundations of the proposed methodologies, detailing the structure and benefits of each convex optimization model. Numerical examples demonstrate the effectiveness of the proposed methodologies in achieving high-performance radiation patterns for circular and planar arrays. The results highlight trade-offs between formulation complexity and pattern performance across different optimization models, providing valuable insights for antenna array pattern synthesis. Overall, this work underscores the potential of convex optimization in antenna array pattern synthesis methodologies.
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Hernawan, Hernawan, Septi Nurhayati, Khoirun Nisa, A. W. Indrianingsih, Cici Darsih, and Muhammad Kismurtono. "FORMULATION AND IN VITRO STUDY OF PROPRANOLOL HYDROCHLORIDE CONTROLLED RELEASE FROM CARBOXYMETHYL CHITOSAN-BASED MATRIX TABLETS." Indonesian Journal of Chemistry 13, no. 3 (2013): 242–47. http://dx.doi.org/10.22146/ijc.21283.
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Formulation and in vitro study of propranolol hydrochloride controlled release from carboxymethyl chitosan-based matrix tablets have been conducted. Formulations with various concentrations of carboxymethyl chitosan 2% (F1), 4% (F2), 6% (F3) were done by wet granulation method. Compatibility test was conducted by XRD and FTIR spectroscopy to determine interaction between propranolol hydrochloride and polymer excipients. Dissolution profiles was obtained through in vitro tests release using simulated gastric fluid (without enzymes, pH 1.2) for the first 2 h and followed by simulated intestinal fluid (phosphate buffer solution without enzyme, pH 7.2) for 2 h remaining. The dissolution profile of each formulation was fitted with five kinetics modeling of drug release (zero order, first order, Higuchi, Peppas-Korsmeyer, and Hixson-Crowell). The compatibility test results showed that formulation caused physical interactions between propranolol hydrochloride and polymer excipient but doesn't make crystallinity nature of propranolol hydrochloride disturbed even after formulation. Dissolution profiles of each formulation showed that controlled release of propranolol hydrochloride from the tablet followed Peppas-Korsmeyer model. It is concluded that carboxymethyl chitosan in appropriate proportions is suitable for formulating propranolol hydrochloride controlled release tablets which exhibit Peppas-Korsmeyer release kinetics.
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Müller, Fabian, Lucas Crampen, Thomas Henneron, Stephane Clénet та Kay Hameyer. "Model order reduction techniques applied to magnetodynamic T-Ω-formulation". COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 39, № 5 (2020): 1057–69. http://dx.doi.org/10.1108/compel-01-2020-0025.
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Purpose The purpose of this paper is to use different model order reduction techniques to cope with the computational effort of solving large systems of equations. By appropriate decomposition of the electromagnetic field problem, the number of degrees of freedom (DOF) can be efficiently reduced. In this contribution, the Proper Generalized Decomposition (PGD) and the Proper Orthogonal Decomposition (POD) are used in the frame of the T-Ω-formulation, and the feasibility is elaborated. Design/methodology/approach The POD and the PGD are two methods to reduce the model order. Particularly in the context of eddy current problems, conventional time-stepping algorithms can lead to many numerical simulations of the studied problem. To simulate the transient field, the T-Ω-formulation is used which couples the magnetic scalar potential and the electric vector potential. In this paper, both methods are studied on an academic example of an induction furnace in terms of accuracy and computational effort. Findings Using the proposed reduction techniques significantly reduces the DOF and subsequently the computational effort. Further, the feasibility of the combination of both methods with the T-Ω-formulation is given, and a fundamental step toward fast simulation of eddy current problems is shown. Originality/value In this paper, the PGD is combined for the first time with the T-Ω-formulation. The application of the PGD and POD and the following comparison illustrate the great potential of these techniques in combination with the T-Ω-formulation in context of eddy current problems.
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Sulbhewar, Litesh N., and P. Raveendranath. "An accurate modeling of piezoelectric smart beams with first-order shear deformation theory." International Journal of Modeling, Simulation, and Scientific Computing 06, no. 02 (2015): 1550022. http://dx.doi.org/10.1142/s1793962315500221.
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A finite element model for piezoelectric smart beam in extension mode based on First-order Shear Deformation Theory (FSDT) with an appropriate through-thickness distribution of electric potential is presented. Accuracy of piezoelectric finite element formulations depends on the selection of assumed mechanical and electrical fields. Most of the conventional FSDT-based piezoelectric beam formulations available in the literature use linear through-thickness distribution of electric potential which is actually nonlinear. Here, a novel quadratic profile of the through-thickness electric potential is proposed to include the nonlinear effects. The results obtained show that the accuracy of conventional formulations with linear through-thickness potential approximation is affected by the material configuration, especially when the piezoelectric material dominates the beam cross section. It is shown that the present formulation gives the same level of accuracy for all regimes of material configurations in the beam cross section. Also, a modified form of the FSDT displacements is employed, which utilizes the shear angle as a degree of freedom instead of section rotation. Such a FSDT displacement field shows improved performance compared to the conventional field. The present formulation is validated by comparing the results with ANSYS 2D simulation. The comparison of results proves the improved efficiency and accuracy of the present formulation over the conventional formulations.
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Pallavi, T., G. S. Sharma, B. Rama, L. Jyothi Rani, and B. Rajkamal. "Formulation and evaluation of floating bilayer tablets of epleronone." World Journal of Pharmaceutical Sciences 10, no. 04 (2022): 08–17. http://dx.doi.org/10.54037/wjps.2022.100402.
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Gastro retentive drug delivery systems have been widely used to prolong retention of dosage forms in stomach. Among the various approaches, the floating bilayer tablets formulation offers sustained drug release as well as prolonged gastric retention, along with the added advantage of liquid oral dosage form. The present study was an attempt to formulate and evaluate floating bilayer tablets of Epleronone by using various polymers like guar gum, ethyl cellulose, SSG, CCS. The prepared floating Bilayered tablets were evaluated for hardness, Weight variation, thickness, friability, drug content uniformity, and in-vitro dissolution studies. Based on various evaluation parameters formulation F3 (IR) & F12 (SR) was selected as optimized formulation. From the above floating buoyancy studies shows that F12 shows higher Total floating time than other formulations. It was observed that Formulations F3 (IR) & F12 (SR) gave maximum drug release within time. All formulations were subjected for drug release kinetics studies viz. Zero order, first order, Higuchi matrix, Peppas model equations and the formulations of sustained release (SR) formulations followed zero order release with non-fickian diffusion mechanism.
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Priyadarshani, Sonawane*1 Ajay Shinde2. "Formulation and Evaluation of Nanoparticulate Drug Delivery System of Benazepril HCl." International Journal of Scientific Research and Technology 2, no. 3 (2025): 314–25. https://doi.org/10.5281/zenodo.15055510.
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The objective of this study was to develop a nanoformulation of Benazepril HCl drug-loaded nanoparticles providing controlled release formulation. The Benazepril hydrochloride, an angiotensin-converting enzyme (ACE) inhibitor, is used in the treatment of hypertension and heart failure. Benazepril HCl nanoparticles were successfully prepared by emulsion solvent evaporation method using ethylcellulose as polymer, polyvinyl alcohol as stabilizer, and ethanol as organic solvent. Four formulations were prepared by changing the concentration of the polymer and stabilizer. Nanoparticles were characterized for percentage yield, particle size, entrapment efficiency, scanning electron microscopy and in vitro drug release. The particle size and stability of the formulations were determined by the HORIBA SZ-100 series particle size analyzer. The particle size of all formulations was found to be within the range of 200-500 nm. The entrapment efficiency of formulation F1, F2, F3, and F4 of Benazepril HCl nanoparticles was found to be 55.78%, 62.1%,60.95%, and 59.52% respectively. The SEM study nanoparticles of Benazepril HCl exhibit smooth surfaces with irregular shapes. In vitro drug release studies were performed in a phosphate buffer of pH 7.4 using dissolution test apparatus. All formulations show 100% drug release at 10 hrs. The cumulative release of Benazepril HCL from its nanoparticles of the selected formulation was fitted to Zero-order, First-order, Second-order, Higuchi’s (matrix) model, Korsemeyer-Peppas model, and Hixson Crowell model.
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Khatsymovsky, V. M. "First-order minisuperspace model for the Faddeev formulation of gravity." Modern Physics Letters A 30, no. 32 (2015): 1550174. http://dx.doi.org/10.1142/s0217732315501746.
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Faddeev formulation of general relativity (GR) is considered where the metric is composed of ten vector fields or a ten-dimensional tetrad. Upon partial use of the field equations, this theory results in the usual GR. Earlier we have proposed some minisuperspace model for the Faddeev formulation where the tetrad fields are piecewise constant on the polytopes like 4-simplices or, say, cuboids into which [Formula: see text] can be decomposed. Now we study some representation of this (discrete) theory, an analogue of the Cartan–Weyl connection-type form of the Hilbert–Einstein action in the usual continuum GR.
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A., Shylaja Rani and D.V. R. N. Bhikshapathi*. "DESIGN AND EVALUATION OF MICROSPHERES LOADED WITH ESOMEPRAZOLE." Indo American Journal of Pharmaceutical Sciences 04, no. 08 (2017): 2334–43. https://doi.org/10.5281/zenodo.844622.
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The current investigation objective was to fabricate Esomeprazole loaded microspheres for the treatment of gastritis. The microspheres were prepared by ionotropic gelation technique using sodium as alginate polymer and calcium chloride as cross-linking agent. The effect of polymer and cross-linking agent on particle size, shape, % yield, entrapment efficiency, and drug release were studied. The prepared microspheres morphology and physicochemical properties of were investigated by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Among the total 14 formulations, S12 formulation was optimized at 1.8% of sodium alginate, 10% of calcium chloride maintained 100rpm for 10min at room temperature. The optimized formulation (S12) In vitro drug release studies were conducted up to 12h in 0.1N HCl showing 95.3% drug release which followed the zero order and Higuchi model (R2 = 0.994, 0.944) respectively, indicating the possible drug release mechanism to be by diffusion. The optimized S12 formulation subjected to stability studies for 6months as per ICH guidelines. Concluded that before and after stability studies no appreciable difference was observed hence the S12 formulation found stable. The data obtained thus suggest that a microparticulate system can be successfully designed for sustained delivery of Esomeprazole and to improve its bioavailability. Keywords: Microspheres, Esomeprazole, release order kinetics, sodium alginate.
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Otsuki, Yu, Peter Lander, Xinjun Dong, and Yang Wang. "Formulation and application of SMU: An open-source MATLAB package for structural model updating." Advances in Structural Engineering 25, no. 4 (2022): 698–715. http://dx.doi.org/10.1177/13694332211022066.
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This paper describes a MATLAB package for structural model updating, named SMU. The SMU package updates parameter values of a finite element model by solving optimization problems utilizing modal properties obtained from sensor measurements. In particular, the package offers three model updating formulations, namely, (1) the modal assurance criterion value approach, (2) the eigenvector difference approach, and (3) the modal dynamic residual formulation. The first two belong to the family of modal property difference formulations. For each formulation, the analytical Jacobian derivative of the objective function is derived and implemented in SMU. Since the formulated optimization problems are generally nonconvex, the global optimality of the solution cannot be guaranteed using off-the-shelf optimization algorithms. In order to increase the chance of finding a better local minimum, the SMU package can perform gradient search from randomly generated starting points. Several examples for the model updating of as-built structures are included in the GitHub package. This paper demonstrates the SMU functionality through model updating of an 18-DOF model and a concrete building frame model.
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Uche, Chidi U., Mercy A. Okezue, Ibrahim Amidu, and Stephen R. Byrn. "Model Adequacy in Assessing the Predictive Performance of Regression Models in Pharmaceutical Product Optimization: The Bedaquiline Solid Lipid Nanoparticle Example." Scientia Pharmaceutica 92, no. 4 (2024): 64. https://doi.org/10.3390/scipharm92040064.
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This study aimed to assess the predictive performance of first- and second-order regression models in optimizing bedaquiline (BQ) solid lipid nanoparticle (SLN) formulations. A three-step central composite design and graphical optimization process was employed. A design of experiments method was used to evaluate the impact of BQ, Tween 80 (T80), polyethylene glycol (PEG), and lecithin on the formulations’ response variables, including Z-average (PSD), polydispersibility index (PdI), and Zeta potential (ZP). Secondly, we quantified the relationship between experimental variables using the regression model coefficients. Lastly, we predicted the responses and verified the models’ adequacies to ensure accurate representation and effective optimization. The first-order polynomial showed poor model adequacy and required further refinement due to its lack of explanatory power and significant predictors. Conversely, the second-order models provided superior fitness, sensitivity to variability, complexity, and prediction consistency. The optimized formulation achieved a desirability value of 0.9998, indicating alignment with the desired criteria. Specifically, the levels of BQ (19.4 mg), T80 (25.2 mg), PEG (39.2 mg), and lecithin (200 mg) corresponded to PdI (0.41), PSD (250.99 nm), and ZP (−25.95 mV). Maintaining a BQ concentration between 10 and 20% and T80 between 15 and 18% is vital for maximizing ZP and minimizing PdI and PSD, ensuring stable SLN formulations. This study underscores the significance of precise model selection and statistical analysis in pharmaceutical formulation optimization for enhanced drug delivery systems.
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Kim, Taehyoun, Changho Nam, and Youdan Kim. "Reduced-Order Aeroservoelastic Model with an Unsteady Aerodynamic Eigen Formulation." AIAA Journal 35, no. 6 (1997): 1087–88. http://dx.doi.org/10.2514/2.201.
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Kim, Taehyoun, Changho Nam, and Youdan Kim. "Reduced-order aeroservoelastic model with an unsteady aerodynamic eigen formulation." AIAA Journal 35 (January 1997): 1087–88. http://dx.doi.org/10.2514/3.13632.
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Bratland, Anne Katrine. "Wave-Generated Current: A Second-Order Formulation." Journal of Marine Science and Engineering 8, no. 6 (2020): 418. http://dx.doi.org/10.3390/jmse8060418.
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In Stokes’ wave theory, wave numbers are corrected in the third order solution. A change in wave number is also associated with a change in current velocity. Here, it will be argued that the current is the reason for the wave number correction, and that wave-generated current at the mean free surface in infinite depth equals half the Stokes drift. To demonstrate the validity of this second-order formulation, comparisons to computational fluid dynamics (CFD) results are shown; to indicate its effect on wave loads on structures, model tests and analyses are compared.
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Grundel, Sara, and Michael Herty. "Model-order reduction for hyperbolic relaxation systems." International Journal of Nonlinear Sciences and Numerical Simulation 24, no. 7 (2022): 2763–80. http://dx.doi.org/10.1515/ijnsns-2021-0192.
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Abstract We propose a novel framework for model-order reduction of hyperbolic differential equations. The approach combines a relaxation formulation of the hyperbolic equations with a discretization using shifted base functions. Model-order reduction techniques are then applied to the resulting system of coupled ordinary differential equations. On computational examples including in particular the case of shock waves we show the validity of the approach and the performance of the reduced system.
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Venkateswara Reddy, B., and K. Navaneetha. "FORMULATION AND EVALUATION OF SUSTAIN RELEASE CYCLOBENZAPRINE HYDROCHLORIDE PELLETS." INDIAN DRUGS 54, no. 05 (2017): 19–25. http://dx.doi.org/10.53879/id.54.05.10262.
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Cyclobenzaprine Hydrochloride is a centrally acting muscle relaxant which is mostly available in the form of tablets and capsules. The present aim of the study was to develop a sustained release formulation of cyclobenzaprine Hydrochloride pellets using powder layering technique. Nine different formulations of pellets were prepared by using different concentrations of Ethyl Cellulose-50, Hypromellose (HPMC), and PEG 6000 of all formulations, F8 formulation was the optimized formulation. The kinetic studies of F8 formulation was best fitted in the First order model as it had the highest value (R2 = 0.981) and it follows non- fickian diffusion. Among all the formulations F8 gave better drug release 85.7% when compared to innovator, F8 was selected as optimized formulation. The optimized formulation was kept for stability studies for 3 months at 40°C /75% RH and 25°C /60% RH and the results indicated that there was no much variation in their physiochemical characteristics and the formulation was found to be stable.
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Posina Rakshitha, B. Deekshi Gladiola, and Cheepurupalli Prasad. "Formulation and biopharmaceutical evaluation of a transdermal patch containing letrozole." International Journal of Pharmaceuticals and Health Care Research 12, no. 4 (2024): 430–37. https://doi.org/10.61096/ijphr.v12.iss4.2024.430-437.
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The skin can be used as the site for drug administration for continuous transdermal drug infusion into the systemic circulation. For the continuous diffusion penetration of the drugs through the intact skin surface membrane-moderated systems, matrix dispersion type systems, adhesive diffusion controlled systems and micro reservoir systems have been developed. Various penetration enhancers are used for the drug diffusion through skin. In matrix dispersion type systems, the drug is dispersed in the solvent along with the polymers and solvent allowed to evaporate forming a homogeneous drug-polymer matrix. The results obtained showed no physical-chemical incompatibility between the drug and the polymers. L5 formulation has been selected as the best formulation among all the other formulations. The in-vitro drug diffusion studies from the formulation were found to be sustained release. All the evaluation parameters obtained from the best formulation were found to be satisfactory. The data obtained from the in-vitro release studies were fitted to various kinetic models like zero order, first order, Higuchi model and peppas model. From the kinetic data it was found that drug release follows Zero order kinetics model release by diffusion technique from the polymer.
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Dong, Guishan, and Xuewen Mu. "A novel second-order cone programming support vector machine model for binary data classification." Journal of Intelligent & Fuzzy Systems 39, no. 3 (2020): 4505–13. http://dx.doi.org/10.3233/jifs-200467.
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The support vector machine is a classification approach in machine learning. The second-order cone optimization formulation for the soft-margin support vector machine can ensure that the misclassification rate of data points do not exceed a given value. In this paper, a novel second-order cone programming formulation is proposed for the soft-margin support vector machine. The novel formulation uses the l2-norm and two margin variables associated with each class to maximize the margin. Two regularization parameters α and β are introduced to control the trade-off between the maximization of margin variables. Numerical results illustrate that the proposed second-order cone programming formulation for the soft-margin support vector machine has a better prediction performance and robustness than other second-order cone programming support vector machine models used in this article for comparision.
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Shiva Kumar, Y., M. Rasagna, and T. Mangilal. "Preparation and Evaluation of Tapentadol Hydrochloride Solid Lipid Nanoparticles." Journal of Drug Delivery and Therapeutics 9, no. 4-A (2019): 618–24. http://dx.doi.org/10.22270/jddt.v9i4-a.3513.
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Tapentadol Hydrochloride is a centrally acting opioid analgesic used for the treatment of musculoskeletal pain. The aim of the present study is to release the drug at a controlled rate by formulating solid lipid nanoparticles using Hot Homogenization method. In the present study SLN’s are prepared by using Glycerol Monostearate and Stearic acid as lipids and Poloxamer-188 as stabilizer in different ratios in order to get the optimized formulation. The solid lipids and drug were evaluated for drug interactions by using FTIR, DSC, and surface morphology by SEM in order to select the effective formulation. The prepared formulations (F1-F12) were evaluated for Particle size, Zeta potential, %Entrapment efficiency, in vitro drug release studies and stability studies. The FTIR spectra revealed that there is no significant interaction between the drug and lipids. SEM images revealed that the particles are spherical in shape with smooth surface. The particle size was found as 101.9 nm, Zeta potential was found as -18.1mV, % Entrapment Efficiency (%EE) was found as 88.7±0.36 and the % drug release was found as 97.8±0.60 in 10 hours following first order release kinetics and Higuchi model. The Tapentadol Hcl loaded SLN’s of F3 formulation shows more effective when compared to all the other formulations. All the results shows that the Tapentadol Hcl SLN’s can be effectively used for treating severe pain by controlling the rate of release at the targeted site. Keywords: Tapentadol Hydrochloride, Glycerol Monostearate, Stearic acid, Poloxamer-188, Hot Homogenoisation method.
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Tsai, Ming-Jun, Wen-Yu Chang, I.-Hui Chiu, I.-Ling Lin, and Pao-Chu Wu. "Improvement in Skin Penetration Capacity of Linalool by Using Microemulsion as a Delivery Carrier: Formulation Optimization and In Vitro Evaluation." Pharmaceutics 15, no. 5 (2023): 1446. http://dx.doi.org/10.3390/pharmaceutics15051446.
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Linalool is an aromatic oil with analgesic, anti-inflammatory and anti-UVB-induced skin damage effects. The aim of this study was to develop a linalool-loaded microemulsion formulation for topical application. In order to quickly obtain an optimal drug-loaded formulation, statistical tools of the response surface methodology and a mixed experimental design with four independent variables of oil (X1), mixed surfactant (X2), cosurfactant (X3) and water (X4) were used to design a series of model formulations in order to analyze the effect of the composition on the characteristics and permeation capacity of linalool-loaded microemulsion formulations and to obtain an appropriate drug-loaded formulation. The results showed that the droplet size, viscosity and penetration capacity of linalool-loaded formulations were significantly affected by formulation component proportions. The skin deposition amount of the drug and flux of such formulations expressively increased about 6.1-fold and 6.5-fold, respectively, when compared to the control group (5% linalool dissolved in ethanol). After 3 months of storage, the physicochemical characteristics and drug level did not show a significant change. The linalool formulation-treated rat skin showed non-significant irritation compared to skin treatments in the distilled-water-treated group. The results showed that specific microemulsion applications might be considered as potential drug delivery carriers for essential oil topical application.
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Sikdar, K. M. Yasif Kayes, Md Islam Molla, Md Hamidur Rahman, and Nazmus Saqueeb. "A comparative study on Naproxen Sodium tablets formulating with different super disintegrants." GSC Biological and Pharmaceutical Sciences 9, no. 3 (2019): 076–84. https://doi.org/10.5281/zenodo.4283221.
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Naproxen, a commonly used non-steroidal anti-inflammatory drug (NSAID), for pain management and immediate release tablet is more patient convenient for managing pain immediately. In this study, six different formulations (F1-F6) of naproxen immediate release tablets were prepared by wet granulation method and were designed to increase disintegration and drug release property by using two super disintegrants named sodium starch glycolate and crospovidone in different concentrations. After preparing the formulations, the physicochemical properties were evaluated according to the United States Pharmacopoeia (USP) guideline. Among all the formulations, F6 proved to be the best immediate release formulation in terms of disintegration time (1.23 min) and dissolution (99.56% after 30 minutes). Other tablet properties of formulation F6 like average weight, diameter, thickness, hardness and friability were also within the USP limit. Drug release kinetics were analyzed through different models such as zero order, first order, Higuchi, Korsmeyer-Peppas and Hixson-Crowell model where the optimized formulation (F6) was best fitted in Hixson-Crowell model. The release mechanism of naproxen followed non-swellable matrix-diffusion, Quasi-Fickian diffusion. Moreover, F6 formulation was stable at 45 °C/ 75% RH for a period of three months and compatibility study was conducted by using Fourier Transform Infrared Spectroscopy (FTIR) where no change was found in stability and peak positions. The optimized formulation (F6) was compared with eight (8) different naproxen immediate release tablet brands (B1-B8) available in market based on dissolution. F6 showed better release property than the marketed tablets. Thus, it can be comprehended that the formulation F6 was robust and stable with a better immediate release property.
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Stive, M. J. F. "A MODEL FOR CROSS-SHORE SEDIMENT TRANSPORT." Coastal Engineering Proceedings 1, no. 20 (1986): 114. http://dx.doi.org/10.9753/icce.v20.114.
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A model for cross-shore sediment transport due to random waves is described which adopts a vertically integrated transport description for sheetflow situations. The formulation of the transport as a function of the instantaneous velocity field is based on the approach of Bailard (1981). This approach assumes in essence that the instantaneous transport is proportional to some power of the instantaneous near-bottom velocity. Implementation of this transport description in a time-dependent model requires a formulation of the time-mean and some low order moments of the near-bottom velocity field. An initial formulation based on a monochromatic, second order Stokes wave representation is presented. The model is checked on the basis of both field and laboratory data. Some consequences for further study are indicated.
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Cuadrado, J., D. Dopico, M. Gonzalez, and M. A. Naya. "A Combined Penalty and Recursive Real-Time Formulation for Multibody Dynamics." Journal of Mechanical Design 126, no. 4 (2004): 602–8. http://dx.doi.org/10.1115/1.1758257.
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The continuously improved performance of personal computers enables the real-time motion simulation of complex multibody systems, such as the whole model of an automobile, on a conventional PC, provided the adequate formulation is applied. There exist two big families of dynamic formulations, depending on the type of coordinates they use to model the system: global and topological. The former leads to a simple and systematic programming while the latter is very efficient. In this work, a hybrid formulation is presented, obtained by combination of one of the most efficient global formulations and one of the most systematic topological formulations. It shows, at the same time, easiness of implementation and a high level of efficiency. In order to verify the advantages that the new formulation has over its predecessors, the following four examples are solved using the three formulations and the corresponding results are compared: a planar mechanism which goes through a singular position, a car suspension with stiff behavior, a 6-dof robot with changing configurations, and the full model of a car vehicle. Furthermore, the last example is also analyzed using a commercial tool, so as to provide the readers with a well-known reference for comparison.
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Karpik, Anna, Francesco Cosco, and Domenico Mundo. "Higher-Order Hexahedral Finite Elements for Structural Dynamics: A Comparative Review." Machines 11, no. 3 (2023): 326. http://dx.doi.org/10.3390/machines11030326.
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The finite element method (FEM) is widely used in many engineering applications. The popularity of FEM led to the development of several variants of formulations, and hexahedral meshes surged as one of the most computationally effective. After briefly reviewing the reasons and advantages behind the formulation of increasing order elements, including the serendipity variants and the associated reduced integration schemes, a systematic comparison of the most common hexahedral formulations is presented. A numerical benchmark was used to assess convergency rates and computational efficiencies when solving the eigenvalue problem for linear dynamic analysis. The obtained results confirmed the superior performances of the higher-order brick element formulations. In terms of computational efficiency, defined as the ratio between achievable accuracy and computational execution time, quadratic or cubic formulations exhibited the best results for the stages of FE model assembly and solution computation, respectively.
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Khadir, Mohamed, and John Ringwood. "Extension of First Order Predictive Functional Controllers to Handle Higher Order Internal Models." International Journal of Applied Mathematics and Computer Science 18, no. 2 (2008): 229–39. http://dx.doi.org/10.2478/v10006-008-0021-z.
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Extension of First Order Predictive Functional Controllers to Handle Higher Order Internal ModelsPredictive Functional Control (PFC), belonging to the family of predictive control techniques, has been demonstrated as a powerful algorithm for controlling process plants. The input/output PFC formulation has been a particularly attractive paradigm for industrial processes, with a combination of simplicity and effectiveness. Though its use of a lag plus delay ARX/ARMAX model is justified in many applications, there exists a range of process types which may present difficulties, leading to chattering and/or instability. In this paper, instability of first order PFC is addressed, and solutions to handle higher order and difficult systems are proposed. The input/output PFC formulation is extended to cover the cases of internal models with zero and/or higher order pole dynamics in an ARX/ARMAX form, via a parallel and cascaded model decomposition. Finally, a generic form of PFC, based on elementary outputs, is proposed to handle a wider range of higher order oscillatory and non-minimum phase systems. The range of solutions presented are supported by appropriate examples.
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Xie, Yan, Bin Deng, Jing Jing Chen, and Dao Kui Li. "High-Order Model of Thermo-Piezoelectric Composited Plate." Advanced Materials Research 721 (July 2013): 291–94. http://dx.doi.org/10.4028/www.scientific.net/amr.721.291.
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A finite element formulation is developed for laminated composite plate bonded with piezoelectric layers. To improve the accuracy of the prediction of the plate deformation, a high order shear deformation theory is used, whereas the through-the-thickness linear temperature field distribution is assumed. For the electric potential, a new high order theory has been used. Numerical results of a piezoelectric laminated plate show the significant impact of piezoelectric coupling and pyroelectric effects on the sensory response. Furthermore, the pyroelectric effects will influence the transverse shear stress insignificantly.
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Braun, A. L., and Armando M. Awruch. "An Efficient Model for Numerical Simulation of the Mechanical Behavior of Soils. Part 2: Applications." Soils and Rocks 36, no. 2 (2013): 171–82. http://dx.doi.org/10.28927/sr.362171.
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A numerical model to simulate the mechanical behavior of soils was introduced in Part 1 of this paper (also published in this issue). Detailed information about the analytical model were presented, where the critical state theory for soil mechanics was considered in the context of the elastoplastic formulation. Moreover, an efficient numerical formulation to deal with nonlinear applications was also presented, featuring important characteristics such as reduced integration techniques, explicit integration of the constitutive equation and a corotational formulation for the kinematical description of the continuum. In this second part of the present work, the numerical model proposed in the previous paper is applied to some classical examples of soil mechanics to demonstrate the applicability of the present formulation. Effects of a geometrically nonlinear approach over the numerical predictions are investigated and comparisons are performed taking into account results obtained by using a geometrically linear model. In addition, some comparisons are also carried out considering evaluations performed with different constitutive formulations in order to observe the mechanical behavior of the soil mass under different constitutive assumptions.
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Kumar, Servesh, and Vishal Soni. "Formulation, Development and Characterization of Sustained Release Formulation of Herbal Extracts." Asian Pacific Journal of Health Sciences 9, no. 2 (2022): 273–76. http://dx.doi.org/10.21276/apjhs.2022.9.2.54.
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Aim: The aim of the present investigation is to design of sustained release dosage form of different extracts that will help in releasing only small quantities of drug over a prolonged period of time. Material and Methods: The different ingredients for formulations are given as in Table 1 below. The measured quantities of drug, HPMC, MCC and NaHCO3 were mixed thoroughly using a mortar and pistil. The granules were punched into tablets using direct compression technique. The blank formulation (or) placebo (HPMC+ MCC+NaHCO3) and polyherbal formulation were also tested using FTIR Spectrometer. The release rate kinetics of the formulations was analyzed and the data obtained were fitted into Zero order, First order, Higuchi model and Kozmeyer Peppas model. Results: The pre-formulation study results obtained on various parameters on granules were found satisfactory. The granules obtained for the batches (F1-F12) were satisfactory. No rat holing, capping or sticking was observed during the flow of granules from the hopper. The maximum weight variation of the tablets was±1.8%, which falls within the acceptable range of±5%, hence the tablets passed the weight variation test. Hardness for tablets of all batches was in the range of 4.92 to 5.35 kg/cm², which falls above the limit of not less than 3.0 kg/cm². The floating lag time ranged from 35 s to 50 s. From the Table 5, it was found that the formulation F11 has the minimum floating lag time of 35 s and maximum total floating time of 15 h with 100.12% drug content. Conclusion: The effect of ingredients in the polyherbal tablet was analyzed, where HPMC contributed as the floating matrix, MCC to increase the bulk density of the tablet and sodium bicarbonate to initiate the dissolution process.
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D. Shivhare, Umesh, Vikrant P. Dorlikar, Kishore P. Bhusari, Vijay B. Mathur, and Bhiku N. Mirani. "Effect of Polymeric Compositions on Pharmacotechnical Properties of Carvedilol Transdermal Film." International Journal of Pharmaceutical Sciences and Nanotechnology 2, no. 1 (2009): 457–64. http://dx.doi.org/10.37285/ijpsn.2009.2.1.10.
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Transdermal films of carvedilol were prepared by using Eudragit RL100 (ERL100) either alone or in combination with Eudragit RS100 (ERS100), hydroxypropyl methylcellulose K 15 LV (HPMC), and ethyl cellulose (EC). The drug release was extended over a period of 24 h from all formulations. The formulation A5 showed 98.33 cumulative % drug releases in 24 h and followed zero order kinetics. The drug transport mechanism was observed to be Fickian. The cumulative % drug diffused through artificial permeation membrane (cellophane A 393) from same formulation was 100.52 % over a 12 h. The mechanism of dug release was governed by Peppas model and the drug diffusion rate followed zero order kinetics. The formulation A5 comprising of polymers ERL 100, ERS 100, EC and HPMC in 7:1:1:1 ratio fulfills the requirement of good TDDS.
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Afnan, Muhammad, Hamza Shakeel, Ghulam Mustafa, Waseem Akram, and Talib Husain. "Formulation, development and optimization of ofloxacin FDDS sustained release for UTI and H. pylori." Journal of Contemporary Pharmacy, Vol 8, (1) 2024 (June 30, 2024): 1–8. https://doi.org/10.56770/jcp2024811.
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Objective: Development & Optimization of Ofloxacin Floating tablets to enhance gastric retention time. Sustained release effect of formulation will reduce the dosing frequency for UTIs and prolonged local effect will benefit against H-pylori infection. Materials: Pre formulation tests were performed which include bulk characteristics and flow properties. Post formulation studies include weight variation, thickness, content uniformity, hardness, friability, dissolution studies, release kinetics and compatibility & stability analysis. Kinetic studies were done and models were applied to understand the drug release mechanism. Accelerated stability analysis was also done for time period of 6 months. Results: All pre formulation tests were within range of USP standards, all the formulations showed good buoyancy. The in-vitro dissolution testing showed that F2 released drug at much slower rate, 64.97% within 24 hrs. F3 & F4 released ofloxacin at faster rate, 98.6% & 99.90% respectively, however, F1 released 91.66% drug within 24 hrs. F1 followed Higuchi model, F2 & F3 followed 1st order kinetics and F4 followed 1st order & Higuchi model. For F1, FTIR & DSC analysis curves showed no interaction or change of state of ofloxacin. Conclusion: Formulation F1 was proved to be the optimized formulation and followed non-Fickian release independent of concentration of drug also confirmed from Korsmeyer-Peppas equation. The Stability analysis also proved that F1 is the best fit formulation to be used as Floating Drug Delivery System of Ofloxacin. Stability analysis proved that polymers used in F1 formulation were effective effervescent agents and made the formulation optimized and efficacious.
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Palma, Cristian D., Francisco P. Vergara, and Sebastián Muñoz-Herrera. "Explicit Modeling of Multi-Product Customer Orders in a Multi-Period Production Planning Model." Mathematics 12, no. 19 (2024): 3029. http://dx.doi.org/10.3390/math12193029.
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In many industries, companies receive customer orders that include multiple products. To simplify the use of optimization models for planning purposes, these orders are broken down, and the quantities of each product are grouped with the same products from other orders to be completed in the same period. Consequently, traditional production planning models enforce minimum demand constraints by product and period rather than by individual orders. An important drawback of this aggregation procedure is that it requires a fixed order fulfillment period, potentially missing opportunities for more efficient resource use through early completion. This paper introduces a novel mathematical formulation that preserves the integrity of customer orders, allowing for early fulfillment when possible. We compare a traditional linear programming model with a new mixed-integer programming approach using a sawmill case study. Although more complex than the traditional model, the proposed formulation reduces costs by approximately 6% by enabling early order completion and offers greater flexibility and control over the production process. This approach leads to better resource utilization and more precise order management, presenting a valuable alternative to conventional production planning models.
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Yaseen, Mariyam, and Niranjan Panda. "Formulation and In Vitro Evaluation of Tropisetron Loaded Microspheres." Journal of Drug Vigilance and Alternative Therapies 01, no. 04 (2021): 143–53. http://dx.doi.org/10.52816/jdvat.2021.1403.
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Tropisetron is a 5-HT3(5-hydroxytryptamine3) receptor antagonist used fortheprevention of chemotherapy-induced nausea and vomiting. In the present study, ethyl-cellulose, sodium alginate and HPMC K15M loaded microspheres of tropisetron were successfully prepared by ionic gelation technique. All the formulations were evaluated forvarious parameters such as drug content, entrapment efficiency, in vitrodissolution study, release kinetic study and stability study. The in vitro dissolution studies showed that tropisetron microspheres formulation F10 havebetter sustained effect over a period of 12 hours which contains all three polymers having a perfect controlled release. The mechanism of release was determined byvarious kinetic equations such as zero-order, first-order, Higuchi, Hixon Crowell, Korsmeyer-Peppas and finding the R2values of the release profile corresponding to each model. Thus, in thepresent study,in vitro drug release kinetic of the best formulation followed zero order release kinetic model and the drug release mechanism was anomalous diffusion. The results of the current study clearly indicate a promising potentialdelivery systemof the tropisetron microsphere as an alternative to the conventional dosage form
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Ghasemi, Mohammadreza, and Eduardo Gildin. "Model order reduction in porous media flow simulation using quadratic bilinear formulation." Computational Geosciences 20, no. 3 (2015): 723–35. http://dx.doi.org/10.1007/s10596-015-9529-0.
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Shamim, Muhammad Babar, Marian Hörsting, and Stephan Wulfinghoff. "Variational Reduced-Order Modeling of Thermomechanical Shape Memory Alloy Based Cooperative Bistable Microactuators." Actuators 12, no. 1 (2023): 36. http://dx.doi.org/10.3390/act12010036.
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This article presents the formulation and application of a reduced-order thermomechanical finite strain shape memory alloy (SMA)-based microactuator model for switching devices under thermal loading by Joule heating. The formulation is cast in the generalized standard material framework with an extension for thermomechanics. The proper orthogonal decomposition (POD) is utilized for capturing a reduced basis from a precomputed finite element method (FEM) full-scale model. The modal coefficients are computed by optimization of the underlying incremental thermomechanical potential, and the weak form for the mechanical and thermal problem is formulated in reduced-order format. The reduced-order model (ROM) is compared with the FEM model, and the exemplary mean absolute percentage errors for the displacement and temperature are 0.973% and 0.089%, respectively, with a speedup factor of 9.56 for a single SMA-based actuator. The ROM presented is tested for single and cooperative beam-like actuators. Furthermore, cross-coupling effects and the bistability phenomenon of the microactuators are investigated.
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Sarma, Himangshu, Taslima Jahan, Ashis Kumar Goswami, and Hemanta Kumar Sharma. "An Experimental investigation based on a Novel Gastro-Retentive Raft Liquid Dosage Form in Tandem with Controlled-Release Strategies for Oral Delivery of Metronidazole." Fabad Journal of Pharmaceutical Sciences 50, no. 1 (2025): 95–110. https://doi.org/10.55262/fabadeczacilik.1573673.
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Background: Peptic ulcers are open sores that develop on the inner lining of the stomach and duodenum. The most common inducer of peptic ulcers includes Helicobacter pylori as the primary pathogen. The present study aimed to design and develop a novel gastro-retentive raft liquid dosage formulation to prolong the gastric retention time of the medicament to treat H. pylori infection. Methods: Metronidazole-loaded raft formulations were prepared using ion-sensitive in situ gel-forming polymers. The formulation was floated within 1 minute on the liquid surface of the in vitro model and maintained floatation for more than 24 hours. Results: Among those formulations, formulation F5 exhibited results within acceptable limits compared with the other batches of formulations. The in vitro drug release was 81.83 ± 0.54 % after 8 hours in 0.1 M HCl. The drug, metronidazole, was released from the dosage form slowly in the stomach. The formulation followed first-order release kinetics, and metronidazole was released from the formulation as a combination of diffusion and erosion mechanisms. Conclusions: Thus, the proposed metronidazole-loaded raft formulation would be a promising novel site-specific drug delivery system and has a potential utility in the therapy of peptic ulcers induced by H. pylori.
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Liu, Pengfei, Liang Xiao, and Liancun Xiu. "Mixed Higher Order Variational Model for Image Recovery." Mathematical Problems in Engineering 2014 (2014): 1–15. http://dx.doi.org/10.1155/2014/924686.
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A novel mixed higher order regularizer involving the first and second degree image derivatives is proposed in this paper. Using spectral decomposition, we reformulate the new regularizer as a weightedL1-L2mixed norm of image derivatives. Due to the equivalent formulation of the proposed regularizer, an efficient fast projected gradient algorithm combined with monotone fast iterative shrinkage thresholding, called, FPG-MFISTA, is designed to solve the resulting variational image recovery problems under majorization-minimization framework. Finally, we demonstrate the effectiveness of the proposed regularization scheme by the experimental comparisons with total variation (TV) scheme, nonlocal TV scheme, and current second degree methods. Specifically, the proposed approach achieves better results than related state-of-the-art methods in terms of peak signal to ratio (PSNR) and restoration quality.
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Lyras, Konstantinos G., and Jack Lee. "An improved reduced-order model for pressure drop across arterial stenoses." PLOS ONE 16, no. 10 (2021): e0258047. http://dx.doi.org/10.1371/journal.pone.0258047.
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Quantification of pressure drop across stenotic arteries is a major element in the functional assessment of occlusive arterial disease. Accurate estimation of the pressure drop with a numerical model allows the calculation of Fractional Flow Reserve (FFR), which is a haemodynamic index employed for guiding coronary revascularisation. Its non-invasive evaluation would contribute to safer and cost-effective diseases management. In this work, we propose a new formulation of a reduced-order model of trans-stenotic pressure drop, based on a consistent theoretical analysis of the Navier-Stokes equation. The new formulation features a novel term that characterises the contribution of turbulence effect to pressure loss. Results from three-dimensional computational fluid dynamics (CFD) showed that the proposed model produces predictions that are significantly more accurate than the existing reduced-order models, for large and small symmetric and eccentric stenoses, covering mild to severe area reductions. FFR calculations based on the proposed model produced zero classification error for three classes comprising positive (≤ 0.75), negative (≥ 0.8) and intermediate (0.75 − 0.8) classes.
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Khaskia, A. M., and A. I. Soler. "A Finite Element Model for General Thick-Walled Shell Structures." Journal of Pressure Vessel Technology 107, no. 2 (1985): 126–33. http://dx.doi.org/10.1115/1.3264424.
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A finite element for general thick-walled structures is presented. The general theory leading to this element is reviewed. A superparametric formulation is adapted. Legendre series expansions of all field variables through the structure thickness are key features in this formulation. “The General Higher Order Theory”—GENHOT element, as we call our element, presented here is capable of predicting the nonlinear distribution, through the thickness, of all stresses and displacements. Test problems with known closed form solution are modeled in order to assess the GENHOT performance. Also, a true thick-walled shell is modeled in order to demonstrate the power and capabilities of this element against a 3-D finite element.
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LISTERUD, EIVIND, and WALTER EVERSMAN. "FINITE ELEMENT MODELING OF ACOUSTICS USING HIGHER ORDER ELEMENTS PART I: NONUNIFORM DUCT PROPAGATION." Journal of Computational Acoustics 12, no. 03 (2004): 397–429. http://dx.doi.org/10.1142/s0218396x0400233x.
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Cubic serendipity elements have been implemented into a nonuniform duct model of acoustic propagation in a moving medium. This model uses a convective potential formulation derived from the inviscid linearized mass and momentum equations. The model requires post-processing to calculate acoustic pressure. These elements outperform the quadratic serendipity elements in terms of computational efficiency based on visual observations and error norm analysis of acoustic pressure. CPU time reduction of up to 40% has been observed without sacrificing accuracy. Any penalty in numerical accuracy incurred by using serendipity elements rather than Lagrangian elements is far outweighed by the gains in dimensionality. The computational gains for calculation of acoustic potential are considerably less. Analytical expressions for the modal and convective effects on the propagating wavelength have been formulated and compared to numerical results. Preliminary assessment of alternative finite element approaches to model the convective potential formulation has been conducted. Stabilization and wave approximation methods have been implemented to solve simple one-dimensional problems.
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Kumar, A. S., B. Ramesh, P. Kavya, V. Deepika, S. Kishore, and K. Babu. "DESIGN, DEVELOPMENT AND CHARACTERIZATION OF SIMVASTATIN LOADED TRANSFERSOMAL GEL FOR TRANSDERMAL DRUG DELIVERY." INDIAN DRUGS 51, no. 12 (2014): 12–17. http://dx.doi.org/10.53879/id.51.12.10159.
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The objective of the present study was to develop a controlled release transdermal drug delivery systems of simvastatin using lipid vesicular systems incorporated in a Carbopol gel, which will control the release of drug, increasing the bioavailability of the drug and thus decreasing the dosing frequency of the drug. The thin film hydration method or conventional rotary evaporation sonication method was used to prepare the transfersomes formulation. Experimental results of the present study showed that deformable lipid vesicles improve the transdermal delivery, prolong the release, and improve the site specificity of the lipophilic model drug, simvastatin. The drug diffusion studies showed that a transfersome vesicle follows zero order and mechanism of release follows Peppas model. In vivo study of optimized transfersomal gel formulation on suitable rodent model showed better biological anti-hyperlipidemic activity in comparison with reference formulation. Lipid:surfactant ratio of 85:15 is more effective when compared to other formulations because of its Higher flexibility and lesser particle size.
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Gracia, Victor, Pablo Krupa, Teodoro Alamo, and Daniel Limon. "Efficient Online Update of Model Predictive Control in Embedded Systems Using First-Order Methods." IEEE Control Systems Letters 7 (December 7, 2023): 3693–98. https://doi.org/10.1109/LCSYS.2023.3341283.
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Model Predictive Control (MPC) is typically characterized for being computationally demanding, as it requires solving optimization problems online; a particularly relevant point when considering its implementation in embedded systems. To reduce the computational burden of the optimization algorithm, most solvers perform as many offline operations as possible, typically performing the computation and factorization of its expensive matrices offline and then storing them in the embedded system. This improves the efficiency of the solver, with the disadvantage that online changes on some of the ingredients of the MPC formulation require performing these expensive computations online. This letter presents an efficient algorithm for the factorization of the key matrix used in several first-order optimization methods applied to linear MPC formulations, allowing its prediction model and cost function matrices to be updated online at the expense of a small computational cost. We show results comparing the proposed approach with other solvers from the literature applied to a linear time-varying system.