Function Of Force Research Articles

Intermolecular Non-Bonded Interactions from Machine Learning Datasets

Accurate determination of intermolecular non-covalent-bonded or non-bonded interactions is the key to potentially useful molecular dynamics simulations of polymer systems. However, it is challenging to balance both the accuracy and computational cost in force field modelling. One of the main difficulties is properly representing the calculated energy data as a continuous force function. In this paper, we employ well-developed machine learning techniques to construct a general purpose intermolecular non-bonded interaction force field for organic polymers. The original ab initio dataset SOFG-31 was calculated by us and has been well documented, and here we use it as our training set. The CLIFF kernel type machine learning scheme is used for predicting the interaction energies of heterodimers selected from the SOFG-31 dataset. Our test results show that the overall errors are well below the chemical accuracy of about 1 kcal/mol, thus demonstrating the promising feasibility of machine learning techniques in force field modelling.

Design of 4-DOF radial floating passive compliant end-effector used for polishing

Manipulators applied to polishing can avoid the harm of dust and noise to workers’ health in manual polishing, and can significantly increase productivity. The degrees of freedom (DOF) of the existing end-effector for manipulator polishing is insufficient, and then it is difficult to adapt to complex surfaces. A passive compliant end-effector (PCEE) with 4-DOF employing pneumatic floating was designed to solve that problem in this article. According to the included angle between the floating spindle and the plunger, the supporting force functions of floating amount were constructed. Considering the characteristics of the supporting force and the operating modes comprehensively, an appropriate number of plungers was selected. Based on the equilibrium principle of spatial force system, a PCEE was designed by using the floating scheme at both ends, and then a physical model and a simplified model were provided. Eventually, the performances of 4-DOF PCEE are compared with those of the existing 2-DOF compliant end-effector (CEE). The results show that The PCEE can float with 4-DOF; when the number of plungers is 9, all performances meet the design requirements; the polishing force can adapt to the local bulges and overcome the error reflection; the 4-DOF PCEE can adaptively fit the surface to reduce its geometric error.

Using Cyclic CBR Method to Determine Resilient Modulus of Hydraulic Binder Stabilised Road Pavement Base Layers

The mechanistic-empirical (E-M) design of pavement structures requires knowledge of the elastic modulus of the layers comprising the structure. The necessary cyclic (dynamic) triaxial testing is expensive and cumbersome for low-volume forest and agricultural roads. Opiyo (1995) developed a method called cyclic CBR (cCBR) to determine the resilient modulus (Mr) of granular road construction materials using CBR testing equipment. The present study tested the cCBR method on silty, fine sand stabilised with lime and a lime-cement mixture. For the test, 24 test specimens were prepared by adding 3, 5 and 7% pure lime and a 70–30 lime-cement mixture at the targeted 8–23% water content. Three metrics were used to express the bearing capacity of the specimens: (1) the commonly used CBR% value, (2) the Mr value calculated as a function of load force and elastic deformation determined as a result of the cCBR test, and (3) the resilient modulus calculated from the CBR value. The experimental results showed that the initial water content had a greater effect on the bearing capacity than the binder dosage. The present study found the cCBR procedure to be feasible. The test results were converted to a resilient modulus value using the formula developed by Opiyo and Molenaar, respectively. The calculated resilient modulus values from the CBR value exhibited a wide variation. Uzan's formula provided similar results to those calculated by Molenaar's formula. A 250 m long experimental road section was also constructed to verify the laboratory data. Based on the laboratory tests, five different 50 m long stabilisation layers were built. The bearing capacity data measured with the handheld BC-1 LFWD and KUAB-FWD equipment verified Molenaar's formula.

Juridical Analysis Of The Implementation Of Compulsory Study At Night On Children In An Effort To Protect And Overcome Youth Delinquency (Research Study In Bintan District)

Children and teenagers are the next generation of the nation and are family and state assets that must be safeguarded and protected in all aspects of their lives, including physical, psychological, intellectual, their rights, and their dignity. Protecting children is not only the responsibility of parents but also the responsibility of all of us. The purpose of this research is to determine the legal basis for the formation of policies for implementing compulsory school hours at night, the differences between the implementation of study hours at night and study hours during the day, goals and objectives, infrastructure, implementation, task force, duties and functions of the task force, and the sanctions and obstacles faced in implementing compulsory education at night. The specification method of this research is analytical descriptive, which describes finding legal facts systematically with the aim of making this research easier to understand and conclude. The results of the research show that there are efforts to protect and prevent juvenile delinquency from the Bintan Regency Government in the form of regional head policy, namely Regent's Regulation Number 66 of 2014 concerning Compulsory Night Study Hours for Children in Bintan Regency, which is in accordance with applicable regulations but is not yet effective because there are several obstacles in its implementation.

Digital model of the drag force of the Earth’s upper atmosphere for the design of low-orbit spacecraft

A digital model is described for estimating the drag force of the Earth's upper atmosphere acting on a low-orbit spacecraft. Unlike the classical model of aerodynamic force, the digital model is the result of a computer algorithm. This algorithm calculates the field of aerodynamic force values, taking into account changes in the flight altitude, aerodynamic coefficient and the area of the spacecraft midsection over time. The calculations also use a digital model of the dynamic density of the Earth's upper atmosphere. The digital model of the drag force of the Earth's upper atmosphere is useful in the design of low-orbit spacecraft with a low-thrust jet propulsion system (thrust order – millinewtons). On the basis of the calculated values of the aerodynamic force, it is possible to form requirements for the geometry of the spacecraft, attitude modes and arrangement of low-thrust jet engines (for example, electric jet engines). With the accumulation of big data in the form of tabular functions of aerodynamic force from the space of various design and ballistic parameters of low-orbit spacecraft, it is possible to create a machine model (ML-model). It will make forecasts of the values of the design characteristics for the low-orbit spacecraft being developed according to a limited set of initial requirements.

Fully coupled peridynamic model for analyzing the chemo-diffusion-mechanical behavior of sulfate attack in concrete

Sulfate attack is an important cause of concrete durability deterioration. A multi-field peridynamic (PD) model is developed to investigate the expansion and cracking behaviour of concrete under sulfate attack. The deformation at the material point is decomposed into expansion and distortion, and an expression for expansion is derived in the PD framework. A novel pairwise force function is constructed to capture the expansion effect. Additionally, a distortion-based damage criterion is established to determine bond failure in expansion-dominated deformation. The mutually reinforcing effects between crack propagation and sulfate diffusion are explored. Several numerical examples are performed to verify the validity and accuracy of the PD model. The results of the coupled PD model exhibit in good agreement with those obtained from the analytical solutions, finite difference method, and experimental findings. The developed model further elucidates the profound interplay between concrete expansion cracking, chemical reaction and expansion process during sulfate attack.

Peptide Orientation Strongly Affected by the Nanoparticle Size as Revealed by Sum Frequency Scattering Spectroscopy.

The orientation of proteins at interfaces has a profound effect on the function of proteins. For nanoparticles (NPs) in a biological environment, protein orientation determines the toxicity, function, and identity of the NP. Thus, understanding how proteins orientate at NP surfaces is a critical parameter in controlling NP biochemistry. While planar surfaces are often used to model NP interfaces for protein orientation studies, it has been shown recently that proteins can orient very differently on NP surfaces. This study uses sum frequency scattering vibrational spectroscopy of the model helical leucine-lysine (LK) peptide on NPs of different sizes to determine the cause for the orientation effects. The data show that, for low dielectric constant materials, the orientation of the helical LK peptide is a function of the coulombic forces between peptides across different particle volumes. This finding strongly suggests that flat model systems are only of limited use for determining protein orientation at NP interfaces and that charge interactions should be considered when designing medical NPs or assessing NP biocompatibility.

An optimized unibond dual-parameter peridynamic model for deformation and fracture simulation of quasi-brittle materials

Peridynamic is a nonlocal theory, which is an effective tool for predicting fracture in solids. The unibond dual-parameter peridynamic (UDPD) model can break through the Poisson's ratio limitation compared with the bond-based peridynamic model. However, the traditional algorithm for the integrated volume is designed according to the analytical value of partial length in the one-dimensional model, which will produce non-negligible errors for the two- and three-dimensional models. Besides, the classical UDPD model is restricted to ideal brittle materials rather than quasi-brittles, and the long-range force effect is generally omitted for simplified analysis. In this work, an optimized UDPD model is developed to overcome the above drawbacks in simulating the deformation and fracture of quasi-brittle materials. First, the novel algorithm to obtain a more accurate integrated volume is introduced into the UDPD model. Second, considering the long-range force effect and the deformation characteristics, the nonlinear constitutive force function coupled with the cosine type influence function is developed for the UDPD model. Then, the corresponding bond stiffnesses are derived. The proposed model is verified through several representative numerical applications, which suggests that the predicted results match well with the experimental observations and former simulations. It is indicated that the proposed model reveals a significant improvement in the convergence and precision of results, which can not only retain the stability of the classical UDPD model, but also precisely analyze the deformation behavior and damage evolution process of quasi-brittle materials.

Effects of the centrifugal force in stellar dynamo simulations

Context. The centrifugal force is often omitted from simulations of stellar convection either for numerical reasons or because it is assumed to be weak compared to the gravitational force. However, the centrifugal force might be an important factor in rapidly rotating stars, such as solar analogs, due to its Ω2 scaling, where Ω is the rotation rate of the star. Aims. We study the effects of the centrifugal force in a set of 21 semi-global stellar dynamo simulations with varying rotation rates. Included in the set are three control runs aimed at distinguishing the effects of the centrifugal force from the nonlinear evolution of the solutions. Methods. We solved the 3D magnetohydrodynamic equations with the PENCIL CODE in a solar-like convective zone in a spherical wedge setup with a 2π azimuthal extent. The rotation rate and the amplitude of the centrifugal force were varied. We decomposed the magnetic field into spherical harmonics and studied the migration of azimuthal dynamo waves (ADWs), the energy of different large-scale magnetic modes, and differential rotation. Results. In the regime with the lowest rotation rates, Ω = 5 − 10 Ω⊙, where Ω⊙ is the rotation rate of the Sun, we see no marked changes in either the differential rotation or the magnetic field properties. For intermediate rotation, Ω = 20 − 25 Ω⊙, we identify an increase in the differential rotation as a function of centrifugal force. The axisymmetric magnetic energy tends to decrease with centrifugal force, while the non-axisymmetric one increases. The ADWs are also affected, especially in the propagation direction. In the most rapidly rotating set with Ω = 30 Ω⊙, these changes are more pronounced, and in one case the propagation direction of the ADW changes from prograde to retrograde. The control runs suggest that the results are a consequence of the centrifugal force and not due to the details of the initial conditions or the history of the run. Conclusions. We find that the differential rotation and properties of the ADWs only change as a function of the centrifugal force when rotation is rapid enough.

Real-time path planning based on improved artificial potential field method

Nowadays, with the development of robotics-related technology, its applications permeate many aspects of work and life; In product manufacturing and assembly, tech companies switch from manual to robot automation which improves the production volume and reduces the assembly time. In the tertiary sector including health and social work, the robots learn how to interact with people to meet specified requirements. Path planning constitutes a critical module of robotics engineering that aims to provide the optimal solution for the robot to reach its target point. The artificial potential field methods, refers to APF, are widely used to realize path planning due to their simplicity of calculation and effectiveness in obstacle avoidance. However, the traditional artificial potential field method features the local minimum and oscillation, and unreachable target point problems that make it hard for robots to reach the target point. Based on the weaknesses, an improved version of the gravitation and repulsion force function was introduced in this paper. In addition, the concept of safety distance also contributed to the path planning for robots. Through the simulation experiment, it was shown that the improved APF algorithm successfully addressed the local minima and unreachable target point problem, which could navigate robots to arrive at the destination in both 2D and 3D space by avoiding collision with obstacles.

A computational study of the calendering processes using Oldroyd 8-constant fluid with slip effects

The analyses of the calendering processes using Oldroyd 8-constant fluid model with the non-linear slip condition effects are discussed in this paper. To model the flow equations for the study of calendering, we utilized the conservation of mass, momentum equations, and Oldroyd 8-constant model. The final equations are reduced into fourth order differential equations by utilizing lubrication approximation theory (LAT). MATLAB’s built-in function bvp4c is employed to calculate the stream function and the fluid velocity. Furthermore, pressure gradient, pressure, and mechanical quantities of calendering processes are obtained by fourth-order Runge-Kutta method. The effects of the slip and material parameters of Oldroyd 8-constant fluid on the physical quantities related to calendering are illustrated via graphical figures. The presence of slip is resistive to length of contract and pressure distribution. On the other hand the pressure showed the increasing trend with increase the value of material parameter ([Formula: see text]). The engineering quantity such as force function show decreasing with increase the values of the slip parameter K. As evident from the study, the material parameters play a crucial role in controlling the pressure, thereby influencing the final sheet thickness and separating force. With an increase in the material parameter [Formula: see text], both the sheet thickness and roll-separating force show a corresponding increase.

Remote Work and City Decline: Lessons From the Garment District

Abstract The dramatic rise of remote work threatens the traditional source of urban growth—the unique ability of dense cities to provide a setting in which firms and employees share productive resources, match needs with skills, and transmit knowledge at low cost. These “agglomeration benefits” have induced cities to pursue clusters of related firms that have served as the basis for local economic development and technological innovation. Remote work reduces the necessity for related firms to co-locate, and its popularity has led commentators to predict significant decrease in city business activity, tax revenues, and services as traditional clusters dissipate. It remains unclear how cities will react to the remote work phenomenon. Prior episodes of cluster decline, however, reveal that cities have difficulty pivoting to new economic models when outmoded ones threaten local decay. Instead, cities tend to support existing clusters, notwithstanding that the impending decline is a function of external forces rather than of local policies. This article addresses the potential mismatch between cluster decline that may flow from remote work and city responses. The article theorizes that continued municipal efforts to support a declining cluster emerge from the ability of affected firms to coalesce, exercise political influence, and exploit fragmented municipal decision making to preserve the status quo, maintain or increase municipal subsidies for the cluster, and deter entry by competitors for city resources. Those strategies impede the city’s transition to a more productive economy in the face of looming cluster decline. The article then turns to the history of the garment industry in New York City to illustrate the theory. That history provides a cautionary tale about how cities should and should not respond to the threats they face from remote work.

Structural function analysis of shear walls in sustainable assembled buildings under finite element model

Abstract With the quick progress of industrialization and urbanization, the construction industry has become one of the largest energy-consuming industries. However, the current prefabricated shear wall focuses on the upgrade of seismic function, with less analysis of the energy efficiency of the overall structure. In this study, a sustainable prefabricated building shear wall that takes into account both energy conservation and stress is first proposed, and then the shear wall is modelled by finite element method (FEM) software. Meanwhile, the force functions of the shear wall model, including concrete strength, axial condensability rate, and aspect rate, and finally the seismic function are verified. The experimental outcomes demonstrate that the maximum difference between the FEM analysis outcomes and the test data is only 10.66%, and the overall difference in the outcomes is relatively small. The larger the aspect rate of the proposed sustainable assembled shear wall model, the better the ductility of the member, and the bigger the axial condensability rate and concrete strength, the lower the ductility of the member. In the seismic function analysis, the maximum layer displacement angles of this shear wall are all less than 1/120, which is in line with the national seismic code. This indicates its good seismic function and provides a methodological reference for the upgrade of the structural function of shear walls.

Force, alternate movements, snap, suction and vibration functions of tongue are altered in oral submucous fibrosis patients

BackgroundOne of the most common clinical manifestations of oral submucous fibrosis (OSMF) is restricted tongue movements. However, the characterization of involvement is needed to better understand the impairment of its functioning. In the present study, force, alternate movements, snap, suction, and vibration functions of the tongue were investigated in OSMF patients. MethodsA total of 53 OSMF and 40 healthy individuals were recruited in the present study. Clinical parameters were used for the diagnosis and grading of OSMF. Alternate movements, snap, suction, vibration of the tongue and tongue force were assessed using standard methodology. ResultsOut of 53 OSMF subjects, 22 (42%) were in early stages and 31 (58%) in late stages. There were statistically significant differences between the OSMF and healthy individuals for tongue functions such as protrusion, retraction, lateral movements, altered snap, suction, and tongue vibration (p < 0.00001). All of the aforementioned tongue functions were more affected in advanced stage OSMF than in early stage OSMF (p < 0.00001). ConclusionForce, alternate movements, snap, suction and vibration functions of tongue are significantly altered in OSMF patients. The performance of the tongue movements by the OSMF subjects worsened with the disease progression.

Research on V2V Time Headway Strategy Considering Multi-Front Vehicles Based on Artificial Potential Field

Within the Internet of Vehicles, the driver’s conduct is more affected by the information about the vehicles in front of them. To meet the driver’s demand for the design of the safety vehicle distance of the adaptive cruise control system in the Vehicle-to-Vehicle (V2V) environment, this paper employs the artificial potential field (APF) theory to enhance the vehicle time headway strategy and constructs a mixed force function in the global force field with three front vehicles as the center of the three potential fields. Taking into account the inadequate control effect of conventional APF in a dynamic environment, this paper describes the relative kinematic characteristics of the vehicles in front and the host vehicle as parameters and obtains the improved APF. The improved strategy based on APF enhances the forward-looking and anti-interference ability of the distance strategy. Also, the strategy presented in this paper can achieve time headway control under all operating conditions and prevent acceleration fluctuations due to switching between various control strategies. For collaborative simulation, this research uses MATLAB/Simulink and Carsim software. The simulation is conducted under three common traffic scenarios, and it is determined that the improved control method results in smoother changes in vehicle speed, acceleration, and car-following distance, hence improving driving and riding comfort.

NEMOH: Open-source boundary element solver for computation of first- and second-order hydrodynamic loads in the frequency domain

NEMOH is developed to solve potential flow problems using the boundary element method for computing wave loads on offshore structures. The solver solves the first-order problem in the frequency domain. An extended module enables computation of the second-order loads on a structure in bi-chromatic bi-directional waves. NEMOH is released as open-source, developed, and distributed under the terms of GNU General Public License (GPLv3). Along with the source code, a user manual is available which facilitates the compilation and execution of the source files. In this new release, NEMOH v3.0 has new features; irregular frequencies removal method, new linear system solvers for enhancing computational efficiency, and a new module for computing the full quadratic transfer function (QTF) of drift forces. Verification cases are shown for a truncated cylinder, a truncated cylinder with a thin heave plate, a spar buoy platform (SOFTWIND), and a semi-submersible platform (OC4). The results are compared with reference data from commercial software, WAMIT, DIODORE, and HYDROSTAR, and the comparison showed that NEMOH v3.0 is accurate and efficient. Program summaryProgram Title: NEMOHCPC Library link to program files:https://doi.org/10.17632/k9v4hjb5xj.1Developer's repository link:https://gitlab.com/lheea/NemohCode Ocean capsule:https://codeocean.com/capsule/9256007Licensing provisions: GPLv3Programming language: FortranExternal libraries and programs: BLAS [1], LAPACK [2]Nature of problem: NEMOH solves the potential flow problems of diffraction and radiation in wave-structure interactions. Typical use is the estimation of the dynamic response of floating structures, e.g. floating offshore wind turbine platforms, or wave-energy converters.Solution method: The linear potential flow problems, diffraction and radiation, are expressed in the boundary integral of the source distribution formulation. The equations are solved in the frequency domain and implemented using the boundary element method with quadrilateral panels. The source distribution on the body panels is obtained by solving the linear system. The hydrodynamic coefficients are computed with the known source distribution. The second-order potential flow problem is not solved directly; the Green formulation is used with an assisting function which is the instantaneous radiation potential, that allows the computation of second-order force for given first-order hydrodynamic quantities.Additional comments including restrictions and unusual features:•The previous version, NEMOH v2.0 [3], was available only for computing first-order hydrodynamic coefficients without the irregular frequency removal method. NEMOH v3.0 has new features, the extended boundary integral method is implemented for removing the irregular frequencies, new linear system solvers are added for enhancing computational efficiency, and a new module is added for computing second-order wave loads. NEMOH v3.0 has better accuracy than v2.0 due to finer interpolation points of the free-surface Green function and a better integration method for constructing the influence coefficients.•For the free-surface piercing bodies problem, it is known that non-unique solutions exist in the boundary integral equation at certain frequencies. In NEMOH, the extended boundary integral equation is applied to remove the irregular frequencies by providing the lid panels on the body waterplane. The second-order loads require the computation of the free-surface forcing terms in the integral forms. These free-surface integrals are essential for the sum-frequency wave loads but may be negligible in the difference-frequency loads. For now, it is suggested not to apply the lid panels when the free-surface integrals are computed.

Novel mesh suture may resist bone cutting seen with wire-based sternal closures.

Sternal dehiscence is frequently associated with wire-based closures cutting through fragile bone, allowing sternal motion, separation, and infection. We investigated whether bone cutting could be limited by using a newly available mesh suture with improved force distribution. Five sternal models were closed using 8 interrupted single sternal wires, double sternal wires, braided poly(ethylene terephthalate) sutures, single-wrapped mesh sutures, or double-wrapped mesh sutures. To simulate chest-wall forces, closed sternal models were pulled apart using 1020N of axial force applied incrementally. Double sternal wire and double-wrapped mesh suture were further compared by closing 3 new models with each material and subjecting these models to cyclic loading cycles, simulating breathing and coughing. Image analysis of needle hole size measured "bone cutting" by each closure material and sternal distraction as a function of force. All models exhibited maximal separation at the xiphoid. During axial loading, needle hole size increased 7.2% in the double-wrapped mesh suture model and 9.2% in the double-wire model. Single-wrapped mesh suture, single wires, and braided poly(ethylene terephthalate) extended needle hole size by 6.7%, 47.0%, and 168.3% of original size, respectively. The double-wire model resisted sternal distraction best, separating 0.285cm at the xiphoid. During cyclic loading, mesh suture exhibited significantly less bone cutting (P=.02) than double wire, with comparable levels of sternal separation (P=.07). Mesh suture may resist bone cutting seen in sternal wire closure in bone models with comparable distraction to currently used sternal closure methods.

Mechanical data corrections for triaxial compression testing at high pressures and high temperatures with a Paterson gas-medium mechanical testing apparatus

Although restricted by a limited range of strain, the triaxial compression test is a mature and common technique for investigating the rheological properties of rock materials at high pressures and high temperatures, especially when establishing the constitutive equations for various flow laws. The Paterson gas-medium high-pressure and high-temperature mechanical testing apparatus (Paterson apparatus) is the best apparatus for triaxial compression testing due to its high stress resolution. However, to derive accurate mechanical information from the raw data recorded by the Paterson apparatus, some technical issues should be addressed, including the simultaneous distortion of the apparatus, the load force supported by the jacketing tube, and the change in the cross-sectional area of the specimen. In this paper, we introduce correction methods corresponding to these three technical issues for triaxial compression on a Paterson apparatus equipped with an internal load cell to significantly reduce experimental errors so that high-precision mechanical data for establishing the constitutive equations of flow laws, such as differential stress, strain, and strain rate, can be obtained. To facilitate corrections for the distortion of the apparatus and the load force supported by the jacketing tube, we determine the distortion of the Paterson apparatus as a function of axial load force by deforming tungsten steel specimens with a known Young’s modulus and the high-temperature flow laws of two common jacketing materials, iron and copper, by triaxial compression experiments at confining pressures of 200–300 MPa. Previous flow laws of iron and copper established by Frost and Ashby (1982) using ambient mechanical data are carefully compared with the flow laws obtained in this study to evaluate their effectiveness for correcting jacket tube strength. Finally, the errors eliminated by each correction step are analyzed and discussed to better understand the necessity of mechanical data corrections.

Mechanism of double diffusive convection due to magnetized Williamson nanofluid flow in tapered asymmetric channel under the influence of peristaltic propulsion and radiative heat transfer

PurposeThe purpose of this study, thermal radiation and viscous dissipation impacts on double diffusive convection on peristaltic transport of Williamson nanofluid due to induced magnetic field in a tapered channel is examined. The study of propulsion system is on the rise in aerospace research. In spacecraft technology, the propulsion system uses high-temperature heat transmission governed through thermal radiation process. This study will help in assessment of chyme movement in the gastrointestinal tract and also in regulating the intensity of magnetic field of the blood flow during surgery.Design/methodology/approachThe brief mathematical modelling, along with induced magnetic field, of Williamson nanofluid is given. The governing equations are reduced to dimensionless form by using appropriate transformations. Numerical technique is manipulated to solve the highly nonlinear differential equations. The roll of different variables is graphically analyzed in terms of concentration, temperature, volume fraction of nanoparticles, axial-induced magnetic field, magnetic force function, stream functions, pressure rise and pressure gradient.FindingsThe key finding from the analysis above can be summed up as follows: the temperature profile decreases and concentration profile increases due to the rising impact of thermal radiation. Brownian motion parameter has a reducing influence on nanoparticle concentration due to massive transfer of nanoparticles from a hot zone to a cool region, which causes a decrease in concentration profile· The pressure rise enhances due to rising values of thermophoresis and thermal Grashof number in retrograde pumping, free pumping and copumping region.Originality/valueTo the best of the authors’ knowledge, a study that integrates double-diffusion convection with thermal radiation, viscous dissipation and induced magnetic field on peristaltic flow of Williamson nanofluid with a channel that is asymmetric has not been carried out so far.

An Equilibrium Strategy for Target Benefit Pension Plans with a Longevity Trend and Partial Information

This paper considers the problem of portfolio selection and adjustment for target benefit plans (TBP) with longevity trends and partial information. The longevity trends are modeled by a time-varying force function. The financial market consists of risk-free assets and stocks, in which the return rate of stocks is a stochastic process and cannot be completely observed. This paper adopts the mean-variance utility model as an optimization criterion. The aim is to maximize the terminal value of the pension fund and the excess pension benefit after the participant’s retirement. The optimization equations are developed in game theory to obtain explicit solutions for the equilibrium strategies. Finally, the influence of the longevity trend on the internal structure of the pension system and the sensitivity of the equilibrium strategies to the related parameters are explored by numerical analysis. The conclusion shows that this model’s results can provide stable and adequate retirement benefits for participants.