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The main purpose of this paper is to present a comprehensive upscale theory of the thermo-mechanical coupling particle simulation for three-dimensional (3D) large-scale non-isothermal problems, so that a small 3D length-scale particle model can exactly reproduce the same mechanical and thermal results with that of a large 3D length-scale one.

The objective is achieved by following the scaling methodology proposed by Feng and Owen (2014).

After four basic physical quantities and their similarity-ratios are chosen, the derived quantities and its similarity-ratios can be derived from its dimensions. As the proposed comprehensive 3D upscale theory contains five similarity criteria, it reveals the intrinsic relationship between the particle-simulation solution obtained from a small 3D length-scale (e.g. a laboratory length-scale) model and that obtained from a large 3D length-scale (e.g. a geological length-scale) one. The scale invariance of the 3D interaction law in the thermo-mechanical coupled particle model is examined. The proposed 3D upscale theory is tested through two typical examples. Finally, a practical application example of 3D transient heat flow in a solid with constant heat flux is given to illustrate the performance of the proposed 3D upscale theory in the thermo-mechanical coupling particle simulation of 3D large-scale non-isothermal problems. Both the benchmark tests and application example are provided to demonstrate the correctness and usefulness of the proposed 3D upscale theory for simulating 3D non-isothermal problems using the particle simulation method.

The paper provides some important theoretical guidance to modeling 3D large-scale non-isothermal problems at both the engineering length-scale (i.e. the meter-scale) and the geological length-scale (i.e. the kilometer-scale) using the particle simulation method directly.

Traditional gas tungsten arc welding (GTAW) and GTAW-based wire and arc additive manufacturing (WAAM) are notably different. These differences are crucial to the process stability and surface quality in GTAW WAAM. This paper addresses special characteristics and the process control method of GTAW WAAM. The purpose of this paper is to improve the process stability with sensor information fusion in omnidirectional GTAW WAAM process.

A wire feed strategy is proposed to achieve an omnidirectional GTAW WAAM process. Thus, a model of welding voltage with welding current and arc length is established. An automatic control system fit to the entire GTAW WAAM process is established using both welding voltage and welding current. The effect of several types of commonly used controllers is examined. To assess the validity of this system, an arc length step experiment, various wire feed speed experiments and a square sample experiment were performed.

The research findings show that the resented wire feed strategy and arc length control system can effectively guarantee the stability of the GTAW WAAM process.

This paper tries to make a foundation work to achieve omnidirectional welding and process stability of GTAW WAAM through wire feed geometry analysis and sensor information fusion control model. The proposed wire feed strategy is implementable and practical, and a novel sensor fusion control method has been developed in the study for varying current GTAW WAAM process.

To investigate the effect of poly ethylene glycol (PEG) chain length on the dielectric properties of paraffin‐based PEG polymers (H(CH₂)_n–(OCH₂CH₂)_mOH) from both experimental and analytical approach.

Dielectric constant studies of paraffin‐based PEG polymers were carried out at temperatures above the melting point. The measurements were carried out at frequencies between 0.4 and 20 GHz. The number of PEG units, m, was varied from 0 to 80 to investigate the effect of the PEG chain length on the dielectric properties of the whole polymer.

With the existence of a dipole moment on PEG but not on pure paraffin, both the real and imaginary part of the dielectric permittivity become larger with increasing chain length of PEG. PEG 3000 showed the highest dielectric constants in the measured frequency range. The effect of the PEG chain length can be explained well by introducing the fraction of molecular weight of PEG divided by the molecular weight of the whole polymer (we call this fraction “Mw fraction of PEG”). Both, real and imaginary part of the dielectric permittivity exhibit a cubic dependence of the molecular weight fraction, and the loss tangent exhibits a linear dependence. These relationships make it possible to predict the microwave heating of the polymer in function of the PEG chain length, carbon chain length and microwave frequency.

For the dielectric permittivity of paraffin‐based PEG polymers, the effect of the PEG chain length, carbon chain length and applied microwave frequency on the loss tangent was explained well by introducing the molecular weight fraction of PEG.

The purpose of this paper is to explore the determinants, transactional alignment and performance outcomes of franchise contract length using transaction costs theory (TCT) and resource-based theory (RBT).

The author hypothesizes that franchisors choose contract length according to TCT and RBT arguments. TCT explains the safeguarding function of contracts: the franchisors will offer longer contracts when franchisees’ specific investments are high and environmental uncertainty is low. RBT highlights the knowledge leverage function of contracts: the franchisors will offer longer contracts when the brand name and intangible knowledge assets are high. Franchise companies that design contract length aligned with transactional attributes will perform better. The author tests the misalignment hypothesis and comparative performance of franchise contracts by estimating two-stage least squares regression and Heckman two-stage procedure that control for endogeneity and self-selection.

Empirical data from the German franchise sector support the hypotheses. In addition to the safeguarding function, franchise contracts have an important knowledge leverage function. Longer contracts perform better due to the development of relational strategic assets and stronger commitment.

Franchisors must offer longer contracts when specific investments of franchisees, brand name, intangible knowledge assets are high, and environmental uncertainty is low. Franchisors should invest in the development of relational strategic assets and offer longer contracts for the benefit of superior performance.

The study addresses the significant question of transactional alignment and comparative performance of franchise contracts. It empirically confirms the importance of RBT in explaining contractual choices and performance.

The purpose of this paper is to examine the effects of length of service and ethical ideologies on cognitive moral development (CMD) and ethical behavioral intentions among public sector tax auditors in Brazil.

The research data were collected via survey questionnaires from a sample of 625 auditors who work for the Brazilian tax authority. Participants voluntarily complete an online instrument which included three scenarios with context-specific moral dilemmas, questions about the specific scenarios and an ethics position questionnaire. Multinomial logistic and ordinary least squares regressions were used to analyze the data.

The findings reveal that public sector tax auditors with shorter length of service are more likely to be at higher stages of moral development; relativistic ideology among public sector auditors is positively associated with more lenient ethical behavioral intention; idealistic ideology among public sector auditors is positively associated with stricter ethical behavioral intention; public sector auditors classified as absolutists are stricter in their ethical behavioral intentions; and public sector auditors classified as absolutists with length of service between 5 and 15 years are more likely to be at higher stages of moral development when compared to public sector tax auditors with longer length of service.

To the best of the authors’ knowledge, the study is one of the first studies that attempt to understand the effects of length of service and ethical ideology on CMD and ethical behavioral intention among public sector auditors. Additionally, it examines these issues in the context of Latin America.

The purpose of this paper is to perform two-dimensional numerical simulation involving fluid-structure interaction of flexible filament. The filament is tethered to the bottom of a rectangular channel with oscillating fluid flow inlet conditions at low Reynolds number. The simulations are performed using a temporal second-order finite volume-based immersed boundary method (IBM). Further, to understand the relation between different aspect ratios i.e. ratio of filament length to channel height (Len/H) and fixed channel geometry ratio, i.e. ratio of channel height to channel length (H/Lc) on mixing and pumping capabilities.

The discretization of governing continuity and Navier–Stokes equation is done by finite-volume method on a staggered Cartesian grid. SIMPLE algorithm is used to solve fluid velocity and pressure terms. Two cases of oscillatory flow conditions are used with the flexible filament tethered at the center of bottom channel wall. The first case is sinusoidal oscillatory flow with phase shift (SOFPS) and second case is sinusoidal oscillatory flow without phase shift (SOF). The simulation results are validated with filament dynamics studies of previous researchers. Further, parametric analysis is carried to study the effect of filament length (aspect ratio), filament bending rigidity and Reynolds number on the complex deformation and behavior of flexible filament interacting with nearby oscillating fluid motion.

It is found that selection of right filament length and bending rigidity is crucial for fluid mixing scenarios. The phase shift in fluid motion is also found to critically effect filament displacement dynamics, especially for rigid filaments. Aspect ratio, suitable for mixing applications is dependent on channel geometry ratio. Symmetric deformation is observed for filaments subjected to SOFPS condition irrespective of bending rigidity, whereas medium and low rigidity filaments placed in SOF condition show severe asymmetric behavior. Two key findings of this study are: symmetric filament conformity without appreciable bending produces sweeping motion in fluid flow, which is highly suited for mixing application; and asymmetric behavior shown by the filament depicts antiplectic metachronism commonly found in beating cilia. As a result, it is possible to pin point the type of fluid motion governing fluid mixing and fluid pumping. The developed computational model can, thus, successfully demonstrate filament-fluid interaction for a wide variety of similar problems.

The present study uses a temporal second-order finite volume-based IBM to examine flexible filament dynamics for various applications such as fluid mixing. Also, it highlights the relationship between channel geometry ratio and filament aspect ratio and its effect on filament sweep patterns. The study further reports the effect of filament displacement dynamics with or without phase shift for inlet oscillating fluid flow condition.

The purpose of this paper is to investigate the chest girth and height related to men’s upper body dimensions to develop men’s grading system for semi-customized clothing.

A data set of the 3,012 men between the age group of 18 and 59 years from 6th Size Korea was used in this study. The men’s upper body dimensions were tested in terms of five horizontal lengths, seven circumferences and seven vertical lengths. Experiment and data analysis were carried out with two methods: one is multiple linear regression with chest girth and height as each independent variable and the other is calculating variation among chest girth size groups and height size groups, respectively.

Regression analysis showed that some horizontal lengths are affected not only by chest girth, but also by height, and some vertical lengths are affected not only by height, but also by chest girth. In variation analysis it was found that the variation value for each part of the body is different and it was observed that with an increase in chest girth vertical length also increases. In variation analysis of height, it is found that some horizontal body dimensions and hip girth increase with an increase in height. In the comparison of upper body dimension variation among height groups with the size based on the chest girth, we found that a tall person who already has long vertical length is less affected by the increase in dimensions by increases in their horizontal girth than a short person.

The findings showed detailed numerical body shape changes according to chest girth and height, and it may be used as the basis for determining pattern grading values by chest girth or height.

The aim of this study was to understand the stick-slip properties of single and multiple yarn pull-out in dry and treated polyester satin woven fabric in boundary regions.

Polyester satin pattern woven fabric was used to conduct the pull-out tests in order to examining the kinetic region of the force-displacement curve. Data generated from this research help the authors to obtain stick-slip force and accumulative retraction force.

It was found that stick-slip force and accumulative retraction force depend on the number of pulled ends in the fabric, fabric sample dimensions and softening treatments. Stick-slip forces of polyester satin fabric in the multiple yarn pull-out test were higher than those of the single yarn pull-out test. Stick-slip force in single and multiple yarn pull-out tests in the dry polyester satin fabric was generally higher than those of the softening treated polyester satin fabric. In addition, the warp directional single and multiple yarn stick-slip and accumulative retraction forces in the dry and softening treated polyester fabrics were generally higher than those in the weft direction in the fabric edges due to fabric density. On the other hand, the amount of stick-slip force was related to the number of interlacement points in the fabric, whereas the amount of accumulative retraction force was related to fabric structural response.

The mechanism of stick-slip and accumulative retraction force of dry-treated polyester satin pattern woven fabrics were explained. This research could be valuable for development of multifunctional fabrics in technical textiles and ballistic.

The study aims to review the literatures on the effect of fiber length on the mechanical response of natural fiber composite will help the researchers to know about the perspective of the various natural fibers in making of composite concerning fiber length. The review summarized the work of the other researchers, thereby unambiguously précised suitability of a specific natural fiber for a matrix in use. Thus, one can identify the use of the same fibers–matrix combination to obtain composites with different properties with the control of fiber/matrix interface.

The review work proposes a new kind of diagrammatic representation that expresses the influence of fiber length. This work has not been explored before in this specific format. The chronology of work may help to select natural fibers for use in composites for a specific matrix.

The length of the fiber perception in terms of “critical” length decides the need for pre-treatment process of natural fiber to improve shear stress at the interface for various matrices.

The current review paper attempts to shed light on the association between the fiber length of natural fiber and the mechanical response of natural fiber composite. Moreover, it probes the concepts of critical fiber length as a persuadable factor.

Asks whether academic workers’ length of service is related to their level of job satisfaction. The enquiry is premised on the assumption that the less satisfied workers tend to resign while the more satisfied ones tend to remain in a job, as some literature suggests. The research distinguishes between length of service in higher education (LSHE) as a whole and length of service in present university (LSPU) in order to separate academics who remain within one university since employment from those who hop from one higher educational institution to another. Two‐way analyses of variance confirm the results of the frequency analyses and indicate that, for direct effects and a 0.05 significance level, LSHE is not statistically significant but LSPU is with a p value of 0.022. This means that the overall job satisfaction of university teachers is significantly correlated with LSPU but not LSHE. The implications are explored.