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Adaptive reuse of building assets is an important approach to sustainability. Adapting a building for new uses often involves complex factors in the decision-making process, particularly in conservation areas. The paper aims to show an evaluation process of the adaptive reuse potential of historic buildings that are subject to change in the Grand Canal area, a world heritage site in Hangzhou, China.

For this purpose, a model has been established with aggregated views of professionals on the degree to which a variety of factors affect the buildings’ potential for adaptive reuse. The model intends to help prioritise some of the buildings in the area for adaptive reuse, which is important for effective allocation of public resources. Interviews with professionals, analytic hierarchy process and the Delphi method have been used to establish the evaluation model. It is then applied to the Grand Canal area to generate indices for buildings’ adaptive reuse potential and the ranking of priority. The indices are generated through public scoring of historic buildings against the variables and calculated through the model.

The paper concludes that the evaluation process is an effective way to engage the public in the decision-making process and to balance conflict interests of various stakeholders in the management of historic building assets in conservation areas.

The research has proposed an evaluation model to help set priority of buildings subject to adaptive reuse and to help distribute public fund effectively. It facilitates wide public engagement in the decision-making progress of adaptive reuse of historic buildings.

This paper aims to propose a novel balance-assistive control strategy for hip exoskeleton robot.

A hierarchical balance assistive controller based on the virtual stiffness model of extrapolated center of mass (XCoM) is proposed and tested by exoskeleton balance assistive control experiments.

Experiment results show that the proposed controller can accelerate the swing foot chasing XCoM and enlarge the margin of stability.

As a proof of concept, this paper shows the potential for exoskeleton to actively assist human regain balance in sagittal plane when human suffers from a forward or backward disturbing force.

This paper aims to assess whether internal procedural justice is directly and indirectly through self-legitimacy connected to external procedural justice among Taiwanese police officers.

Survey data used in this study were collected from 316 Taiwanese police officers in 2019. Structural equation modeling was performed to examine the direct and indirect relationships between internal and external procedural justice.

Supervisors' internal procedural justice is directly related to the external procedural justice rendered to the public by police officers. Internal procedural justice also directly enhances officers' perceptions of internal legitimacy and external legitimacy. Greater senses of internal legitimacy are then accompanied by higher external procedural justice.

Survey data collected from a non-random sample of officers limit the study findings' generalizability. Organizational justice in the form of supervisory justice is instrumental in promoting officers' perception of self-legitimacy and their delivery of fair treatment to the public.

The present study represents a first attempt to link two important veins of studies in recent policing literature, organizational justice and officer self-legitimacy. This study provides needed evidence to support the value of supervisory justice in policing in a non-Western democracy.

This paper aims at understanding tribological properties of lubricating oils doped with zinc dithiophosphate(ZDDP) with and without electromagnetic field impact.

The friction and wear properties of the oils formulated with zinc butyloctyl dithiophosphate (T202) or zinc dioctyl dithiophosphate (T203) under electromagnetic field or nonelectromagnetic field were evaluated on a modified four-ball tribotester. The characteristics of the worn surfaces obtained from electromagnetic or nonelectromagnetic field conditions were analyzed by scanning electronic microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy. This paper focuses on understanding influence of electromagnetic field on lubrication effect of the ZDDP-formulated oils.

The electromagnetic field could effectively facilitate anti-wear and friction-reducing properties of the oils doped with T202 or T203 as compared to those without electromagnetism affection, and the T203-doped oils were more susceptible to the electromagnetic field. The improvement of anti-wear and friction-reducing abilities of the tested oils were mainly attributed to the promoted tribochemical reactions and the modification of the worn surfaces (forming Zn-Fe solid solution) induced by the electromagnetic field.

This paper has revealed that tribological performances of ZDDP-doped oils could be improved by the electromagnetic field and discussed its lubrication mechanisms. Investigating tribological properties of additives from the viewpoint of electromagnetics is a new attempt, which has significance not only for the choose and designing of additives in electromagnetic condition but also for development of tribological theories and practices.

This paper aims to analyze the temperature field and the heat transfer performance of the counter rotating dual rotor bearings (CRDRB) based on the air phase flow field at different speeds to provide effective support for the lubrication and the thermal design of CRDRB.

In this study, taking H7006C angular contact ball bearing as an example, based on the flow visualization technique and the thermal analysis methods, the effects of outer ring speed on the air phase flow field, the temperature field and the heat transfer in bearing cavity were investigated.

Results indicated that there were more complex turbulent air vortices in CRDRB cavity. Turbulent cyclones in critical contact zone reduced the heat dissipation capacity of air. Compared with single rotor bearing with a static outer ring, the average heat transfer coefficient reduced by 11.78% and the average temperature raised by 3.06 K inside CRDRB cavity. Under the influence of outer ring rotation, the high temperature area in ball-inner raceway contact zone and pocket raised and reduced by 160.13% and 30.48%, respectively. The outer ring rotation had opposite effect on the heat dissipation of raceway contact zone and pocket.

The air phase flow field characteristics and the heat transfer performance of CRDRB were revealed and analyzed from the mechanism. An area quantification method was presented as an auxiliary mean of the thermal analysis to evaluate the heat transfer performance of bearing.

This paper aims to investigate the effects of air inlet flow rate on the bearing cavity and operating conditions during the oil-air lubrication.

A model of oil-air lubrication of rolling bearings is established using computational fluid dynamics numerical simulation. Moreover, temperature and vibration experiments are carried out for comparisons and validation.

Results suggest that the velocity and pressure distributions of the oil-air flow inside the chamber are not uniform. Moreover, the uniform decreases with increasing air inlet flow rate. The non-uniform oil distribution inside the bearing significantly influences the bearing temperature rise and lubrication effect. Furthermore, the decrease in pressure uniformity enhances the vibration intensity and increases the amplitude of the vibration acceleration by more than 40 per cent. Increasing the air inlet flow rate improves lubrication and cooling efficiency but produces intense vibrations.

A method of establishing rolling bearings model under oil-air lubrication is presented in the paper. The effect of air inlet flow rate on flow uniform under oil-air lubrication has been researched insightfully. The results provide a useful reference to improve the oil-air lubrication system and enhance the operational stability of the motorized spindle.

Teacher well-being has been a concern, but there has been a lack of research on how teacher leadership can contribute to teacher well-being in a high-accountability context and a hierarchical education system such as that of China, particularly through the meditating roles of trust in the leader and teacher efficacy. Therefore, the purpose of this study was to understand the relationship between teacher leadership and teacher well-being while exploring the mediating roles of trust in leaders and teacher efficacy in this relationship.

Using structural equation modeling (SEM) and bootstrap methods with valid answers from 1,144 teachers in 25 primary schools in 1 Chinese city, this study mainly answered three questions: Is there a significant relationship between teacher leadership and teacher well-being? Is there a significant mediating effect of trust in leaders on the relationship between teacher leadership and teacher well-being? Is there a significant mediating effect of teacher efficacy on the relationship between teacher leadership and teacher well-being?

This study reported a positive relationship between teacher leadership and teacher well-being. This study also found positive mediating roles for trust in leaders and teacher efficacy in the relationship between teacher leadership and teacher well-being in a high-accountability and hierarchical system like that of China.

This study provides an understanding of the transferability of teacher leadership theories across cultures and has practical significance for educational practice in high-accountability and hierarchical education contexts similar to that of China.

The purpose of this paper is to propose a model of assembly strategy generation and selection for human and robot coordinated (HRC) cell assembly. High‐Mix, Low‐Volume production in small production manufacturing industry, tends to employ more flexible assembly cells. The authors propose innovative human and robot coordinated assembly cells to solve the problem of persistent growing cost for human resources and occasional changes in programs and configurations for robots. The first issue is to find out an optimal way to allocate the assembly subtasks to both humans and robots.

A dual Generalized Stochastic Petri Net (GSPN) model is theoretically studied and then off line built based on a practical assembly task for human and robot coordination. Based on GSPN, Monte Carlo method is carried out to study the time cost and payment cost or possible strategies, and Multiple‐Objective Optimization (MOOP) method related Cost‐effectiveness analysis is adopted to select the optimal ones.

It is discovered that human and robot coordinated assembly can reduce the assembly time and meanwhile reduce the assembly cost. The authors demonstrate the effectiveness of this approach by comparing the simulation and experimental results.

The novelty with this work is that the human and robot coordinated flexible assembly cell, as the authors proved, is the main stream in small production in future due to the higher human source pressure from society and cost pressure upon the company. Based on this innovative work, the authors proposed a dual GSPN model to model the assembly task allocation process for human and robot, the model of which is also effective in modeling the possible robot and human behaviors.

The existing Nonlinear Dynamic Vibration Absorbers (NLDVAs) have the disadvantages of complex structure, high cost, high installation space requirements and difficulty in miniaturization. And most of the NLDVAs have not been applied to reality. To address the above issues, a novel Triple-magnet Magnetic Dynamic Vibration Absorber (TMDVA) with tunable stiffness, only composed of triple cylindrical permanent magnets and an acrylic tube, is designed, modeled and tested in this paper.

(1) A novel TMDVA is designed. (2) Theoretical and experimental methods. (3) Equivalent dynamics model.

It is found that adjusting the magnet distance can effectively optimize the vibration reduction effect of the TMDVA under different resonance conditions. When the resonance frequency of the cantilever changes, the magnet distance of the TMDVA with a high vibration reduction effect shows an approximately linear relationship with the resonance frequency of the cantilever which is convenient for the design optimization of the TMDVA.

Both the simulation and experimental results prove that the TMDVA can effectively reduce the vibration of the cantilever even if the resonance frequency of the cantilever changes, which shows the strong robustness of the TMDVA. Given all that, the TMDVA has potential application value in the passive vibration reduction of engineering structures.