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In high-speed processing, the influence on the machining accuracy of a machine tool is greatly caused by the thermal deformation of the motorized spindle; a further study on the thermal characteristics of the spindle is given in this paper. This study aims to reduce the thermal error and improve the performance of the machine tool by discussing the relationships between the temperature distributions and rotating accuracy caused by the thermal deformations of the spindle.

The paper opted for a method combining the theoretical analysis and the experimental study to study the thermal stability of the high-speed motorized spindle. First of all, a finite element model of the spindle was built with ANSYS, whereby temperature distributions and the thermal deformations were successively obtained at different speeds. And then, both the temperature field and the rotating accuracy of the motorized spindle were measured simultaneously by the thermal stability experiment. Finally, the experimental and theoretical results were compared and validated.

The thermal stability of the motorized spindle was studied in this paper, and some findings from the study were as follows: the spindle’s rotating accuracy maintained good in X direction but bad in Y and Z directions in terms of the deformations; the higher front-end temperature of the spindle which can significantly affect the rotating accuracy is needed to be controlled mainly; the recovery speed of the spindle deformation lagged behind the temperature’s fallback speed; the vibration graph about radial rotating sensitivity synthesized by X1 and X2 presented a trifoliate shape.

Based on a built test-bed which can synchronously measure the motorized spindle’s temperature distribution and rotating accuracy with five-point method, the coupling effects of the thermal deformation and temperature are embodied, and not only the vibration graph but also the thermal tilt angles can be gained. Therefore, considering the influence of the thermal deformation on the heat generated by the bearings, the paper fulfilled a study by which it was obtained that the front-end temperature of the spindle, which was higher and could significantly affect the rotating accuracy, needed to be controlled mainly.

The aim of this study is to understand thermal effects and surface topography of roller bearings with misaligned load under combination of multifactors by an experimental method.

A series of orthogonal experiments would need to be planned and performed. A ranking of impact degree of factors on edge effect and eccentric load effect can be learned with multivariate analysis of variance by Statistical Product and Service Solutions software. Influence rules of each individual factor can also be obtained through more experiments. A roller surface phase diagram both before and after test can be observed with metallographic microscope. An axial profile data of roller can be measured by PGI 3D Profiler, then a roller generatrix contour can be achieved through filtering measured signal with empirical mode decomposition method.

Slip fraction has most impact on edge effect, whereas tilting angle plays a key role in eccentric load effect. For the case of low temperature, skidding damage does not occur. Inversely, because of the high pressure in partial elastohydrodynamic lubrication caused by roller tilt, running-in occurs and micro asperity flattening is observed on a rough surface. And, the larger the tilting angle, the more obvious the micro-flattening and the greater the reduction of roller surface roughness after the test.

A lot of theoretical studies on thermal effect of roller bearings surface morphology have been published. However, there are little on relevant experimental study, especially on thermal effect with an integration of sliding, tilting and unbalance loading.

The mobile medical consultation (MMC) service is growing rapidly, but not all consumers are always willing to actively engage with it. To address this issue, based on IT identity theory, this study explores the underlying mechanism of how two types of platform-related consumer experience influence MMC platform identity, in turn, result in consumer negatively-valenced engagement in MMC.

The data was collected from 400 consumers with the experience of MMC and analyzed by the partial least square (PLS) method.

The findings unfold that these two distinct consumer experience, servicescape experience (i.e. perceived telepresence and perceived platform surveillance) and service search experience (i.e. perceived diagnosticity and perceived serendipity), are associated with MMC platform identity and consumer negatively valenced engagement with MMC.

Research on consumer negatively-valenced engagement in the field of MMC is still in a nascent stage. The study identifies consumer experience in accordance with the unique context of the MMC platform and fills the research gap on the role of IT identity in consumer negatively valenced engagement.

To research involvement of healthcare staff in the UK and identify practical organisational and policy solutions to improve and boost capacity of the existing workforce to conduct research.

A mixed-method study presenting three work packages here: secondary analysis of levels of staff research activity, funding, academic outputs and workforce among healthcare organisations in the United Kingdom; 39 Research and Development lead and funder interviews; an online survey of 11 healthcare organisations across the UK, with 1,016 responses from healthcare staff included for analysis; and 51 interviews of healthcare staff in different roles from six UK healthcare organisations.

Interest in research involvement is strong and widespread but hampered by a lack of systematic organisational support despite national policies and strategies to increase staff engagement in research. While useful, these external strategies have limited universal success due to lack of organisational support. Healthcare organisations should embed research within organisational and human resources policies and increase the visibility of research through strategic organisational goals and governance processes. A systems-based approach is needed.

The research gathered data from a limited number of NHS trusts but these were purposively sampled to provide a range of different acute/community health service organisations in different areas. But data was therefore more detailed and nuanced due to a more in-depth approach.

The findings are relevant for developing policies and practice within healthcare organisations to support research engagement. The findings also set out key policy and strategic recommendations that will support greater research engagement.

Increased research activity and engagement in healthcare providers improves healthcare outcomes for patients.

This is a large scale (UK-wide) study involving a broad range of healthcare staff, with good engagement of nurses, midwives and Allied Healthcare Professionals who have not been previously achieved. This allowed valuable analysis of under-researched groups and comparisons by professional groups. The findings highlight the need for tailored action to embed research reporting, skills, professional development and infrastructure into organisational policies, strategies and systems, along with broader system-wide development.

Three types of PbTe samples, e.g. nanoparticles, nanowires and bulk ingots, have been prepared. The investigation of the Seebeck coefficient of PbTe nanoparticles and nanowires clearly shows the sign change in the temperature range of 575~650 K, which is not observed for bulk ingots. Unfortunately, this temperature range is within the proposed operation temperature range for thermoelectric devices using PbTe and hence, such a change will affect their proper performance. The observed sign change of Seebeck coefficient is not simply caused by the composition variation at high temperature. It is mainly attributed to the extrinsic-to-intrinsic-semiconductor transition for PbTe nanocrystals due to the competing factors between quantum size effect increasing band gap and self-purification process decreasing their charge carrier concentration, which shift the transition point of nanocrystals to lower range as compare to that of bulk samples. Thus, such phenomenon should be considered carefully in the design of thermoelectric devices using semiconductor nanocrystals, which have attracted much attention recently.

Farmland transfer choice is strongly associated with the livelihood strategies of rural households. The 2014 Three Property Rights Separation (TPRS) reform has legalized farmland transfer practices in rural China, hence stimulating the farmland transfer market at the national scale. This paper aims to determine the extent to which rural family livelihood strategies are influenced by their participation decision in farmland transfer practices. Further, the authors examined the effectiveness of the TPRS reform on the impact of farmland transfer participation on rural household livelihood strategy choices.

Based on the sustainable livelihood approach (SLA) using data from a national rural household survey, the authors employ the logit model and the propensity score matching (PSM) method to estimate the impact of household farmland transfer participation. Its interaction effects with household livelihood capital on their livelihood strategy choices and diversification level are also investigated. The difference-in-difference (DID) model is employed to assess the effectiveness of the TPRS reform.

The results indicate that the participation in transferred-out farmland could improve rural households' non-agricultural livelihood strategies. While the participation in transferred-in farmland could improve the probability of rural families' engaging in pure-agricultural (PA) or agricultural-dependent (AD) livelihood strategies, the TPRS reform can attract specialized farmers to increase their farm size through the market solutions and encourage small farmers to leave their farmland to engage in more off-farm work.

This study contributes to the literature on farmers' livelihood by exploring the role of farmland transfer decision and the effectiveness of 2014 TPRS reform through the SLA approach.

The purpose of this study was threefold: (1) to measure farmers' health poverty, (2) to examine the effect of health vulnerability on health poverty and (3) to identify countermeasures that may alleviate health poverty in rural China.

This study built a health poverty measurement model based on the multi-dimensional poverty framework to evaluate farmers' health vulnerability. Further, this paper used an econometric model to assess the impact of health vulnerability on health poverty. The sample for this study comprised 1,115 rice farmers from Hubei province, China.

The medical affordability poverty ratio was 17.95%, where farmers in the low-income group faced severe medical affordability poverty (27.46%). Results from the multi-dimensional analysis showed that, the health poverty ratios were 17.95 and 30.50%, respectively. Our results indicated that climate change vulnerabilities, living habits, medical facilities and medical accessibility were positively related to health poverty, whereas the regular physical examinations reduced mental health poverty.

Based on this study's findings, we proposed that: (1) to address illness-induced poverty among members of the agricultural community, national and provincial strategies and programs grounded on a multi-dimensional health poverty framework ought to be formulated and implemented, (2) mechanisms of health knowledge exchange may facilitate the improvement of farmers' health status, (3) robust and comprehensive metrics should be employed to understand and improve farmers' ability to absorb and mitigate the negative health impacts and (4) the improvement in both quality and quantity for medical facilities and medical affordability in the rural areas should be key priorities in governmental-wide initiatives.

Existing studies for alleviating poverty caused by disease mainly focus on medical service support to those economic vulnerabilities after a disease happens. However, few studies have focused on the root causes of poverty caused by disease, particularly from the preventive perspective of health vulnerability. To fill this gap, this study, therefore, proposes the health poverty index and analyzes the impact of health vulnerability on health poverty.

The purpose of this paper is to improve the properties of metal nanoparticles which are easy to agglomerate and hard to disperse evenly, thus limiting the application of metal nanoparticles in grease. A novel technology was proposed for modifying metal oxide to improve the dispersibility of nanoparticles.

SA-TiO2 nanoparticles were synthesized using an in-situ esterification method followed by surface modification with stearic acid. The microstructure of the nanoparticles was characterized by scanning electron microscope, transmission electron microscope and Fourier transform infrared spectroscopy and their thermal stability was evaluated by thermogravimetric analyzer. The tribological properties of the SA-TiO2 nanoparticles as additives in lithium grease were evaluated with a four-ball tester and TE77 reciprocating friction tester. The worn surfaces of the steel balls were investigated by EDS and XPS.

The prepared nanoparticles can be well dispersed in the lithium grease and possess much better tribological properties compared to traditional nanoparticles. The results indicated that the excellent tribological performance of SA-TiO2 was attributed to the chemical reaction film composing of Fe2O3, iron oxide and other organic compounds.

This paper provides a method to prevent the agglomeration of nano-TiO2 by surface modification with stearic acid. And the prepared nanoparticles can effectively improve the tribology performance of lithium grease.

Research on the effects of feedback frequency has reported mixed findings. To tackle this problem, the current study focuses on specific feedback signs (i.e. negative feedback). By integrating the face management theory and attribution theory, this study examined the mediating effect of trust in supervisors and the moderating effect of employee-attributed performance promotion motives for negative feedback.

A field study with 176 participants and two supplemental experiments with 143 and 100 participants, respectively, were conducted to test the theoretical model.

Results revealed that the frequency of supervisory negative feedback negatively influenced employees’ trust in supervisors, which in turn influenced employees’ perceptions of feedback utility and learning performance. These indirect effects can be alleviated when employees have high degrees of performance promotion attribution for supervisor motives.

This research extends feedback research by integrating feedback frequency with a specific sign of feedback and revealing a moderated mediation effect of the negative feedback frequency.

The purpose of this paper is to present a novel high-precision relative navigation method for tight formation-keeping based on thrust on-line identification.

Considering that thrust acceleration cannot be measured directly, an on-line identification method of thrust acceleration is explored via the estimated acceleration of major space perturbation and the inter-satellite relative states obtained from space-borne acceleration sensors; then, an effective identification model is designed to reconstruct thrust acceleration. Based on the identified thrust acceleration, relative orbit dynamics for tight formation-keeping is established. Further, using global positioning system (GPS) measurement information, a modified extended Kalman filter (EKF) is suggested to obtain the inter-satellite relative position and relative velocity.

Compared with the normal EKF and the adaptive robust EKF, the proposed modified EKF has better estimation accuracy in radial and along-track directions because of accurate compensation of thrust acceleration. Meanwhile, high-precision relative navigation results depend on high-precision acceleration sensors. Finally, simulation studies on a chief-deputy formation flying control system are performed to verify the effectiveness and superiority of the proposed relative navigation algorithm.

This paper provides a reference in solving the problem of high-precision relative navigation in tight formation-keeping application.

This paper proposes a novel on-line identification method for thrust acceleration and shows that thrust identification-based modified EKF is more efficient in relative navigation for tight formation-keeping.