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The purpose of this study is to investigate the dynamic behavior of the ball bearing with cage broken.

By analyzing the complicated relationship and interactions among the ball bearing elements, the dynamic modelling of the ball bearing with broken cage was established, and the dynamic simulations were conducted by solving the ball bearing dynamic equations using varying-step Runge–Kutta integration.

The computational results show that there is considerable distinguishment in the dynamic characteristics between the normal cage and the broken cage of the bears. The broken cage makes the trajectory of the cage erratic, and the vibration amplitude is much bigger than that of the normal cage, which makes the motion of the cage unstable. When one of the cage lintels breaks up, the two adjacent balls will collide with each other; what is worse, this may make the balls crush because of the high amplitude of the collision force. The broken cage makes the cage-race interaction force much larger than that of the normal cage, which could promote the guiding ring and quicken the cage wear-failure.

This study can provide important ideas for the fault identification of the ball bearing with cage broken.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2020-0042/

Distance is the core concept in tourism. However, previous studies focused on single distance dimensions and generated contradictory findings due to omitted variable biases. This paper aims to introduce the well-established CAGE (cultural, administrative, geographical, and economic) distance framework into international tourism research to measure the comprehensive distance and explore its impact on inbound tourist satisfaction.

The comprehensive distance was calculated based on the Mahalanobis formula. Combining tourist review data from TripAdvisor, this study used ordinary least square regressions to explore the influence of the comprehensive distance on inbound tourist satisfaction and the mediating role of inbound tourist emotion.

Results show that CAGE distance effectively describes the dynamic change in distance. The comprehensive distance also positively impacts tourist satisfaction, and tourist emotion plays a mediating role in this impact.

This paper advances knowledge about distance in international tourism by introducing the CAGE distance framework and addresses the contradictory findings with specific distance dimensions by the comprehensive distance.

距离是旅游的核心概念。然而, 以前的研究集中在单一的距离维度上, 并且由于遗漏变量偏差而产生了相互矛盾的结果。 本文旨在将成熟的 CAGE 距离框架引入国际旅游研究中, 以衡量综合距离并探讨其对入境游客满意度的影响。

综合距离根据马氏距离公式计算。 结合TripAdvisor网站的游客评论数据, 采用普通最小二乘（OLS）回归分析综合距离对入境游客满意度的影响以及入境游客情绪的中介作用。

结果表明, CAGE距离有效地描述了距离的动态变化。 综合距离也正向影响游客满意度, 游客情绪在此影响中起中介作用。

本文通过引入 CAGE 距离框架来提升国际旅游中的距离知识。 本研究还通过综合距离解决了特定距离维度的矛盾发现。

La distancia es el concepto central en el turismo. Sin embargo, estudios previos se han centrado en dimensiones de una sola distancia, generando resultados contradictorios debido a los sesgos por la omisión de variables. Este trabajo tiene como objetivo introducir el marco de distancia CAGE, establecido en la investigación turística internacional, con la intención de medir la distancia integral y explorar su impacto en la satisfacción del turista receptor.

La distancia integral se calculó con base en la fórmula de Mahalanobis. Combinando los datos de reseñas turísticas de TripAdvisor, se utilizaron regresiones de mínimos cuadrados ordinarios (OLS) para explorar la influencia de la distancia integral en la satisfacción del turista receptor y el papel mediador de la emoción del turista receptor.

Los resultados muestran que el modelo CAGE describe el cambio dinámico en la distancia de una forma efectiva. La distancia integral también impacta positivamente en la satisfacción del turista, y la emoción del turista juega un papel mediador en este impacto.

Este documento avanza en el conocimiento sobre la distancia en el turismo internacional mediante la introducción del marco de distancia CAGE. Además, aborda resultados contradictorios con las dimensiones de distancia específicas mediante la distancia integral.

This case was primarily researched using academic research papers, industry reports (Egg Industry Center and others), and finance databases including Standard and Poor’s Capital IQ. Regarding the cost and investment budgets, the case relies mainly on an experiment conducted by the Coalition for Sustainable Egg Supply, updated by the authors of this case.

Eggs produced by cage-free birds, while more expensive than conventionally produced eggs, are gaining in popularity among consumers who want only eggs that are produced more humanely. A number of major distributors, including Whole Foods, McDonalds and Starbucks have pledged to sell only cage-free produced eggs by 2025. Several states including California, Oregon and Michigan have passed laws limiting conventional egg production. The case provides costs and industry information and needed to project free cash flows and risk-adjusted opportunity cost of capital and perform break-even capital budgeting analysis of the two egg production alternatives.

This case is appropriate for graduate corporate finance courses. It is particularly appropriate for agribusiness finance courses. A preliminary exercise was used during the fall 2018 in a land grant university, just after the “Prevention of Cruelty to Farm Animals Act,” also known as Proposition 12, was passed in California in favor of cage-free egg production. The exercise was revised and used in the fall 2019 in the same class. This extended version of the case, was classroom tested in the fall 2020 in an agribusiness finance graduate class, with agricultural economics and business students enrolled.

This study aims to analyze the roller dynamic characteristics and cage whirling of tapered roller bearing considering roller tilt and skew which provide a theoretical basis for the design and application of tapered roller bearing.

Based on rolling bearing dynamic analysis, the dynamic differential equations of tapered roller bearing are established. Fine integral method and predict correct Adams–Bashforth–Moulton multi-step method are used to solve the dynamic differential equations of tapered roller bearings.

Friction at the flange contact between roller and large flange is the chief factor of roller skew. In comparison to cone speed, axial loads have more visible effect on roller skew, and proper speed or axial load is beneficial to sustain cage motion and decrease cage instability. Under the combined effort of axial load and radial load, the distribution of roller skew is correlated to the roller-flange contact load. In addition, roller skew angle in loaded zone is larger than that in unloaded zone; hence, it is helpful for cage stability if an extent radial load is applied. The pocket clearance of cage has very small influence on roller skew; therefore, a reasonable pocket clearance is suggested to assure minimum instability of cage. Friction coefficient of flange contact has a large effect on roller skew, and cage whirl is found to demonstrate a circular orbit with increasing friction coefficient.

The dynamic differential equations of tapered roller bearing considering roller large end/inner ring back face rib contact under various lubrication states were established. The impact of flange friction working conditions and cage pocket clearance on cage instability and roller skew were focused on. It is the first time that the ratio of the standard deviation of the cage-center translational speed to its mean value is used to access the instability of cage in tapered roller bearing.

The purpose of this study is to investigate the effect of roller dynamic unbalance on cage stress.

Considering the impact of roller dynamic unbalance, the dynamic analysis model of high-speed cylindrical roller bearing is established. And then the results of dynamic model are used as the boundary conditions for the finite element analysis model of roller and cage to obtain the cage stress.

Roller dynamic unbalance affects the contact status between roller and cage pocket and causes the overall increase in cage stress. The most significant impact on cage stress is roller dynamic unbalance in angular direction of roller axis, followed by radial and axial directions. Smaller radial clearance of bearing and a reasonable range of pocket clearance are beneficial to reduce the impact of roller dynamic unbalance on cage stress; the larger cage guide clearance is a disadvantage to decrease cage stress. The impact of roller dynamic unbalance on cage stress under high-speed condition is greater than that in low-speed conditions.

The research can provide some theoretical guidance for the design and manufacture of bearing in high-speed cylindrical roller bearing.

Aims to establish the critical score and screening accuracy of the CAGE Questionnaire in three treatment settings – primary health care, walk‐in (triage) clinic and the emergency room.

Taguchi methods are applied to three screens of the CAGE questionnaire.

Analysis of the sensitivity and specificity data of three CAGE screens by leveling factor (p′), signal‐to‐noise ratios (S/N, SS/N) and their dependent relation resulted in critical CAGE scores of 1, 1 and 2; and high screening accuracy levels of 98.44, 97.20 and 94.92 percent, respectively. The illustrated method yielded excellent (≥95 percent) screening accuracy values for primary health care, emergency room and walk‐in clinic patients.

To reduce misclassification rates of alcohol abuse, screening systems should concentrate first on developing ways to standardize protocols. Further work is needed to establish high screening accuracy in other clinical settings, and particularly in those at risk of alcohol abuse in the general population.

The purpose of this paper is to study the influence of the cage dynamic unbalance on the dynamic performances in cylindrical roller bearings.

The dynamic analysis model which considering cage dynamic unbalance is presented, and the relationship between the cage dynamic unbalance and the cage stability, the cage slip ratio and the cage skew angle is investigated.

Cage dynamic unbalance has a great effect on the cage stability. The cage dynamic unbalance which in an axial excursion affects the cage characteristics is greater than that only in the radial direction. The cage slip ratio and the cage skew increases with the cage dynamic unbalance, especially with the axial excursion. The non-metal cage is more sensitive to the cage dynamic unbalance than that of the metal cage.

The analytical method and model can be applied by the bearing engineering designers.

This study aims to uncover the influencing mechanism of the tilt angles of the cage pocket walls of the high-speed cylindrical roller bearing on the bearing skidding.

A novel cylindrical roller bearing with the beveled cage pockets was proposed. Using the Hertz contact theory and the elastohydrodynamic and hydrodynamic lubrication formulas, the contact models of the bearing were built. Using the multibody kinematics and the Newton–Euler dynamics theory, a dynamics model of the bearing was established. Using the Runge–Kutta integration method, the dynamics simulations and analysis of the bearing were performed.

The simulation results show that the effects of the tilt angles of the front and rear walls of the pocket on the bearing skidding are remarkable. Under a 5° tilt angle of the front wall of the pocket and a 10° tilt angle of the rear wall, the bearing skidding can be effectively decreased in the rotational speed range of 10,000-70,000 r/min.

In this paper, a novel cylindrical roller bearing with the beveled cage pockets was proposed; a dynamics model of the bearing was established; the influence mechanism of the tilt angles of the front and rear walls of the pocket on the bearing skidding was investigated, which can provide fundamental theory basis for optimizing the pocket.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2020-0035/

The purpose of this paper is to investigate the effect of the cage-pocket wear on the dynamic behavior of the ball bearing.

Through analyzing the complicated relationship and interactions among the ball bearing elements, the dynamic modeling of the ball bearing was established considering the gravity, drag force from the oil, hydrodynamic effect on the cage and the dynamic simulations with different amounts of the cage-pocket wear loss of the ball bearing (BPWL) were obtained by solving the ball bearing dynamic equations using Runge–Kutta method.

The results show that the trajectory of the cage’s centroid presents two vibration modes with different amplitudes. In addition, those two different forms of trajectory of different amplitudes emerge alternatively with BPWL increase moreover the diameter of the trajectory decrease significantly with the BPWL increasing, which is consistent with the experimental result and last BPWL has lightly effect on the average skidding ratio of the cage, however, the BPWL would produce significant effects on the fluctuation of the skidding ratio, which can directly reflect the stability of motion to a certain extent.

Practice shows that the bearing failure resulting from the cage accounts for 25 per cent of the total failure of the rolling bearings. However, few discussions about how the wear of the cage-pocket would influence the dynamic characteristics of the cage. This study can provide important ideas for the design of bearing cage-pocket size and the fault identification of the ball bearing to decrease the failure rate caused by the cage.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2019-0535/

The purpose of this paper is to investigate the effects of different faulty scenarios on the induction motor (IM) operation with emphasis on the currents in the rotor bar and end rings.

The modeling of the IM followed by a graphical representation-based analysis of the rotor steady-state currents under healthy operation is treated. Then, a case study is considered in order to investigate different faulty scenarios with a focus on the rotor cage currents.

It has been found that the rotor faults greatly affect the currents in the bars and in the end rings both in amplitude and in harmonic content. These vary according to the relative positions with respect to the fault such that: the currents in the bars adjacent to the faulty one(s) have the highest amplitudes with the lowest harmonic content; and the ones in the ring portions adjacent to the faulty one have the lowest amplitudes with the highest harmonic content.

Although the simulated model has confirmed the well known IM behavior under healthy operation, it would be appreciated if the obtained results under faulty operation would be validated by finite element analysis.

It is of great interest to investigate the effects of faulty scenarios on the rotor cage currents, in order to take appropriate actions starting from the design of the IM.

A deep investigation (including the waveforms, the phasor diagrams and the harmonic content) of the effects of different faulty scenarios on the IM rotor cage currents represents the major contribution of this work.