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During the operation of a wet clutch, there are fluctuations in speed and torque, which have an impact on the stability of the clutch and the strength of the friction plate and the spline pair of the dual steel plate. The purpose of this study is to investigate the vibration characteristics of the wet clutch and the dynamic load characteristics of the spline pairs.

The spline pair model is established by the piecewise linear function method, and on this basis, dynamic equations considering the spline pair of dual steel plates and friction plates are established. Considering that the wet clutch has multiple spline pairs, an equivalent model of the number of teeth and the equivalent model of the tooth width were proposed, and the Runge-Kutta numerical method was used for the wet clutch for these two models.

The research results show that the equal tooth number model has greater meshing stiffness and smaller fluctuation than the constant tooth width model, which shows that increasing the meshing stiffness of the system is beneficial to reduce system fluctuation and improve system stability.

The friction plate has the system that multiple splines are independent of each other, which is relatively complicated. Therefore, an equivalent calculation is performed on multiple pairs of steel plates (friction plates) to simplify the calculation of the spline pairs.

This paper provides a theoretical basis for further dynamic characteristics analysis of wet clutch and reducing fluctuation of speed and torque.

Dynamic equation considering the spline pair of the dual steel plates and the friction plates is established to study the vibration characteristics of the wet clutch and the dynamic load characteristics of the spline pair, etc.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2023-0078/

This paper aims to explore the influence of applied pressure on the tribological properties of the friction component in a wet multi-disc clutch during the running-in process.

The running-in evolutionary was explored in terms of global friction performance. The variation of friction torque and mean COF of the initial 300 engagement cycles was obtained by full-scale tests. Finally, an optical microscope was used to detect the wear characteristics of friction surfaces.

The applied pressure showed a significant influence on the tribological behaviors of wet clutches during the running-in process. The mean COF decreased and then increases with the increase of the applied pressure. A higher applied pressure contributed to more asperity summits being sheared, thus resulting in a smoother surface. Considering a suitable wore performance, properly applied pressure is necessary.

The results provide theoretical guidance for selecting the optimal applied pressure in the running-in of wet clutches.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2022-0256/

Hydro-viscous drive (HVD) clutches are widely used in equipment requiring soft start, such as fans and pumps, to transmit torque and adjust speed by changing the gap distance between friction pairs. This paper aims to propose a novel two-parameter evaluation method for HVD during the mixed lubrication stage. The objective is to develop an effective model that establishes the relationship between these parameters and the actual surface topography.

In the presented methods, the fractal features of the real manufacturing surface are calculated based on the power spectrum function by the ultra-depth three-dimensional microscope. After that, the hybrid friction model of the friction plate is established based on mixed elasto-hydrodynamic lubrication theory, boundary friction model and fractal theory. Then the torque and load bearing characteristics of the clutch are obtained, and the influences of the surface fractal features are investigated and discussed. Finally, the Weierstrass–Mandelbrot function is adopted for the surface topography characterization and evaluation.

The results indicate that the proposed method exhibits good accuracy, while the speed difference between the friction pair exceeds 2,500 rpm. It is concluded that this paper proposed a way to evaluate the torque and loading capacity of HVD considering the real manufacturing surface topography and is helpful for surface optimization.

The originality and value of this study lie in its development of a novel torque and load bearing capacity evaluation method for HVD in mixed lubrication stage, considering manufacturing surface topography and describing the real manufacturing surface.

Magnetic fluid has excellent function used as lubricants in bearings and mechanical seals, and the purpose of this study is to investigate the sealing performance in a spiral groove mechanical seal lubricated by magnetic fluid.

The sealing characteristic parameters of the lubricating film between the end faces of two sealing rings were calculated based on the Muijderman narrow groove theory for a spiral groove mechanical seal lubricated by magnetic fluid. The film thickness was determined according to the balanced forces on the rotating ring, and the effects of operating conditions, intensity of the magnetic field and diameter of nanoparticles on the sealing characteristics were investigated.

It has been found that the intensity of magnetic field has a great effect on the viscosity of magnetic fluid, film thickness and friction torque while has a little effect on the mass flux of magnetic fluid. The film thickness, mass flux of magnetic fluid and friction torque increase with the increasing volume fraction, rotating speed and diameter of magnetic nanoparticles in magnetic fluid. The mass flux of magnetic fluid decrease with the increasing closing force, and the friction torque decreases with the increase of media pressure.

The change of intensity of magnetic field can affect the viscosity of magnetic fluid and then changes the sealing performance in a mechanical seal lubricated by magnetic fluid. To reduce the mass flux of magnetic fluid and friction torque, the volume fraction, diameter of solid magnetic particles and film thickness should be 5%–7%, 8–10 nm and 2–9.3 µm, respectively.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2023-0032/

Bearing friction moments are important factors that affect the vibrations of rotor systems. The bearing friction moments are related to the dimension parameters, lubrication conditions and manufacturing errors of support bearings. This work studies the effects of the bearing friction moments on the vibrations of rotor systems.

The rotor is separated into several shaft elements for formulating a flexible rotor. The time-varying friction moment (TFM) is affected by the time-varying contact loads. The vibrations of FRS from the TFM and Palmgren's friction moment (PFM) calculation methods are compared. Moreover, the effects of the rotor offset and radial clearance on the frequency-amplitude characteristics of FRS are studied.

The TFM method is more consistent with the actual operation mechanisms. The rotor offset and radial clearance can significantly affect the nonlinear vibrations of FRS. This work provides a new reference and research method for the vibration analysis of rotor systems considering the friction effects.

The elastohydrodynamic lubrication (EHL), elastic hysteresis and differential sliding are considered. A flexible rotor system (FRS) dynamic model considering the TFM is proposed. The vibrations of FRS from the TFM calculation method and empirical calculation formula are compared. The effects of the rotor offset and radial clearance on the frequency–amplitude characteristics of FRS are studied.

This case study aims to understand the criticalities of hiring in a knowledge-based start-up; the various ways of retaining talent in a knowledge-based start-up; the competency requirements of human resource professionals in start-up organizations; the trade-off between business profitability and the R&D drive of the company; and the various organizational structures available for a knowledge-based start-up.

Ayush Jain, a first-generation entrepreneur, is facing a challenge with his start-up, TechShlok. TechShlok is an IT solution provider with its headquarters in Jaipur, India. The company is doing very well and is able to achieve many accolades. As the company grows in business and employee strength, it is facing talent acquisition and retention challenges. Ayush is in a fix to solve the talent issue and retain the key talent of the organization.

The case can be taught in a Human Resource Management course, including “talent management” and “human resource planning”. The case may be taught at upper undergraduate levels. It can also be taught in courses of entrepreneurship and knowledge-based start-ups.

Teaching notes are available for educators only.

CSS 11: Strategy.

The urban environment is perceived through multiple senses in parallel, which means that visual understanding of space is aided and complemented by auditory, basic-orienting, and haptic stimuli – although mainly unconsciously. Sensory conditions are inherent attributes of urban places, but are often overlooked in research. To include these aspects in any way in analysis of the urban landscape, they need to be understood as properties of urban space, to be translated from attributes of the perceiver to attributes of the perceived. Using the relation between a designed garden and its suburban context in Bad Oeynhausen (DE) as an example, I will explore an alternative analytical methodology that takes the first-hand perspective view of the subject moving through the city as the starting point. The human body explores space by moving through it; walking is the most direct way to access, study, and research the physical qualities of the (urban) landscape, involving not only visual experience but also sound, rhythm, kinaesthesia, balance, and so forth. A notation technique that discloses the interrelation between visual qualities and their perception over time is the technique of ‘scoring’. Scores are symbolisations of processes, which extend over time. They can objectively represent non-visual qualities of space, communicating the relation between such processes and their spatial context to others in other places and other moments. These representations of movement expose the qualities of the surroundings that change as one moves through them, thus communicating the experiential aspects of urban landscape.

The purpose of this paper is to use a wear test to determine the effect of sand on the wear rates of materials typically used in aerospace applications. Once a repeatable wear test has been established, it can be used to test any combination of materials or coatings. The effectiveness of several different test methods will also be evaluated, including the sample height, surface roughness and mass difference. In addition, the current work will observe the differences between applying sand before the samples are brought into contact or after. The wear rates obtained from these tests could also be used to predict the wear of other components in similar abrasive particulate environments.

A modified block-on-flat wear test of anodized aluminum on hard coat anodized aluminum was used to study this. The experiments were performed with and without sand to study the effects of the sand. Two methods of adding sand were also evaluated. Weighing and profilometry were used to study the differences between the tests.

Wear rates have been calculated based on both the change in the masses of the samples and the change in the height between the upper and lower samples over the course of each test. The wear rates from the change in the masses are repeatable with and without sand, but the results for the change in height show no repeatability without sand. In addition, only in the presence of sand do the trends for the two methods agree. The wear rate was found to be non-linear as a function of load and therefore not in agreement with Archard’s Wear Law. The wear rate also increased significantly when sand was present in the contact for the duration of the test. The sand appears to change the wear mechanism from an adhesive to an abrasive mechanism. Black wear particles formed both when there was sand and when there was not sand. The source of these particles has been investigated but not determined.

This work has not been previously published and is the original work of the authors.

On completion of this case study, students will be able to understand collaboration and synergy between farmers and organisations through value creation, like fundraising, based on the comprehension of the resource-based theory; understand the overview and concept of the value chain and supply chain management in the agribusiness to reduce costs of inventories; understand the concept of segmentation and positioning to increase revenue for organisations by leveraging existing resources – human and financial; and understand the branding strategy to create a sustainable competitive advantage for Suguna Foods.

Suguna was started by two brothers, B. Soundararajan and G.B. Sundararajan, to help other farmers. Suguna, with just 200 broilers in 1984, grew to be the number 1 poultry company across India. Soundararajan was a pioneer and innovator who started “contract farming” in India in 1991. This model helped both the farmers and the company to became successful. The farmers always struggled to pay the cost of feed and other materials, as credit was not readily and easily available from financial institutions. Suguna helped farmers by providing feed, medicines, etc., free of cost in return for the good rearing of chickens. Because of the success of this venture, they decided to continue with it. Today, Suguna is a successful company that sells chicken, eggs and processed meat. They modernised the retail chain to supply consumers with fresh, healthy and hygienic meat. Suguna’s vision was to “Energize rural India” by helping farmers succeed. They helped over 40,000 farmers from 15,000+ villages in 18+ Indian states. Although the growth helped both farmers and Suguna, the increased cost of raw materials for Suguna and increased input costs/power costs for farmers had to be tackled on a war footing so that both could have good income despite the increased inflation. Moreover, the retail price of live chicken was more or less stagnant in the past five years, especially after the start of the COVID-19 pandemic.

This case can be used as the basis for a 90-min class discussion. This case study is suitable for use in an master of business administration course module or in an executive education program on developing an understanding of value creation in the business model in a rural market and also how the supply chain works. This case study can also be used to teach pricing, segmentation in marketing and supply chain perspectives and decision-making skills.

Teaching notes are available for educators only.

CSS8: Marketing.

The study aims to examine the impact of social assistance schemes introduced by the Indian government on poverty alleviation in urban slums.

To accomplish the study's objectives, primary data were collected from 585 beneficiaries of government schemes operating in India's northwestern state using a multistage sampling technique (Punjab). The exploratory factor analysis (EFA) technique reduced the total dataset to its minimum factors. Then, using second-order confirmatory factor analysis, the data's validity and reliability were determined. The data were analyzed using statistical techniques such as one-way ANOVA, t-test and structural equation modeling (SEM).

The study's findings indicate that social assistance provided by the Government of India has a direct and substantial influence on poverty alleviation in urban slums. The study demonstrates how access to basic credit financial services through social assistance programmes has improved the lives of urban poor households living in slums and assisted them in escaping poverty.

The investigation was undertaken among a few limitations. First, the in-depth investigation of the study is restricted to only the northwestern state of India solely because of limited resources and time availability. Second, the study focuses primarily on the perspectives of beneficiaries of the social assistance schemes in India. Still, it might be expanded in the future to include additional stakeholders such as bank executives, business colleagues and municipal town panchayats.

Due to policymakers' increased emphasis on poor households living in urban slums, this topic is critical for studying many issues.

The research explores gaps in social welfare schemes to direct policymakers and government authorities to take appropriate steps to aid the urban poor people in sliding out of poverty.

By examining the influence of the Indian government's social welfare schemes on poverty reduction in slums, this study contributes to the literature on public assistance schemes and poverty alleviation. This article can assist policymakers in developing nations in increasing financial capability among disadvantaged urban families on a national and international level.