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The purpose of this paper is to measure the craniofacial dimensions of 41 full‐term neonates nursed in the Special Care Baby Unit of Queen Mary Hospital in Hong Kong, so as to develop a good‐fitting and secure eye‐patch protector for protecting neonatal eyes from the strong light in phototherapy.

In total, 14 craniofacial dimensions were measured using a new, safe and non‐intrusive method with a close‐range photogrammetric system and two dimensions of head circumference and facial arc were measured using manual method with a disposable paper tape in the hospital environment. Birth information of gestation, age, gender, present weight and present length has been recorded. A descriptive statistics was produced based on the measured data. Correlations between each pair of dimensions were investigated and factor analysis was conducted for application on an eye‐patch protector development.

Head circumference was identified as the most desirable key dimension of a sizing system for an eye‐patch protector. Two head circumferences with the sizes of 310‐349 mm and 350‐389 mm, respectively, could effectively cover all full‐term neonates. Design guidelines were generated according to the measurement of the craniofacial dimensions.

This paper presents the craniofacial dimensions of head, eye, nose and ear parts of full‐term neonates.

Current lubrication analyses of misaligned journal bearings are generally performed under some given preconditions. The purpose of this paper is to calculate the lubrication characteristics of a journal bearing with journal misalignment caused by shaft deformation under load, considering the surface roughness, thermal effect and (thermal and elastic) deformation of bearing surface simultaneously.

The lubrication of bearing was analyzed by average flow model based generalized Reynolds equation. The deformation of bearing surface under pressure or heat of oil film was calculated by compliance matrix method. The compliance matrix was established by finite element analysis. The temperature distributions of oil film and bearing were calculated by energy equation and heat conduction equation.

When the thermal deformation of bearing and journal surface is considered, the radius clearance affects not only the value of the maximum oil film pressure and minimum oil film thickness, but also the distribution of oil film pressure and thickness of misaligned bearing. The effect of thermal deformation of bearing on the performance of misaligned bearing is larger than that of elastic deformation of bearing. Whether or not the surface roughness affects the performance of misaligned bearing and the affecting level depends greatly on the condition of deformation of bearing surface.

The surface roughness, thermal effect and (thermal and elastic) deformation of bearing surface were considered simultaneously in the thermoelastohydrodynamic lubrication analysis of bearing with journal misalignment caused by shaft deformation under load. The results of this paper are helpful to the design of the bearing.

The purpose of this study is solving the hand–eye calibration issue for line structured light vision sensor. Only after hand–eye calibration the sensor measurement data can be applied to robot system.

In this paper, the hand–eye calibration methods are studied, respectively, for eye-in-hand and eye-to-hand. Firstly, the coordinates of the target point in robot system are obtained by tool centre point (TCP), then the robot is controlled to make the sensor measure the target point in multiple poses and the measurement data and pose data are obtained; finally, the sum of squared calibration errors is minimized by the least square method. Furthermore, the missing vector in the process of solving the transformation matrix is obtained by vector operation, and the complete matrix is obtained.

On this basis, the sensor measurement data can be easily and accurately converted to the robot coordinate system by matrix operation.

This method has no special requirement for robot pose control, and its calibration process is fast and efficient, with high precision and has practical popularized value.

This paper aims to examine the day-to-day within-person associations between employees' flow experience and organizational identification within the rarely studied context of construction engineering project organizations.

In this daily diary design, the authors surveyed 204 (M_age = 28.3, SD = 5.69) employees of a state-owned construction engineering project organization in southwest China via the online questionnaires comprising flow and organizational identification scales once daily on each workday for three consecutive weeks, which yielded 3,060 data entries. The authors then tested the temporal directionality between flow and organizational identification with multilevel time-series cross-lagged path analysis using Mplus 8.3.

Daily flow experience was linked positively with same-day organizational identification. Importantly, flow experience on the previous day predicted organizational identification on a subsequent day, but not vice versa.

This study suggests that construction engineering project managers should implement interventions fostering the employees' flow experience to promote organizational identification, with important implications for organizations aiming at flourishing workforces by facilitating organizational identification through implementing flow strategies.

There is a dearth of diary studies on flow and organizational identification specific to construction engineering project employees. The authors’ findings provide concrete evidence of the fluctuant nature of daily flow experience and organizational identification as well as their dynamic predictive pathway relationship.

This paper aims to describe a simple low-pass filter to suppress torque pulsation and current harmonics in permanent magnet synchronous motor (PMSM) drives.

For the control of the PMSM, a field-oriented control algorithm is always used. The proposed filter is actually a resistance, inductance, capacitance (RLC) filter. At the output of the inverter and the input of PMSM, an RLC filter is connected. This filter suppresses current harmonics through filtering phase voltage harmonics. Analysis of the filter is achieved through frequency characteristics analysis.

This filter can effectively filter out the harmonic of phase voltage. Both the simulation and experiment results show that the proposed filter can effectively suppress torque pulsation and current harmonics in PMSM drives. Also, the method of selecting filter parameters and the whole control system are very simple.

The filter increases the design cost of the system.

The harmonics and torque ripple of phase current are greatly suppressed. Also, the loss of the PMSM reduced.

The method of selecting filter parameters and the analysis of the proposed filter are proposed for the first time.

This paper aims to test the predictability of the three asset classes, namely direct property, bond and property stocks in Singapore.

Using the generalized method of moment (GMM) estimation methodology, the authors first estimate the excess returns of assets on five instrumental variables and a constant term. Next the common risk factors are tested in three parts involving different portfolio of sample assets.

The empirical results shows that there are at most three common risk factors that can be used to predict the excess returns of six asset classes, that include four direct property assets, bonds and property stocks. The results also indicate that there are separate common risk premia that are priced in property stock and direct property markets, which indirectly reject the hypothesis that the two property markets are integrated.

The empirical results that reject the market integration between property and property stock markets imply that there are significant diversification benefits for holding both assets in investors' portfolios. The two property assets capture different risk premia in the markets.

The GMM specifications that include five instrumental variables may not fully capture all risk information. Omission of other variables is, however, traded‐off against the parsimony of the model specification. More independent variables could be included in the future studies, and more asset classes could also be added to the tests.

The study provides alternative evidence to the test of market integration between property and property stocks in Singapore. It also verifies the earlier study in the USA that property and stock market effects could be separately priced by the market.

The purpose of this paper is to provide additive manufacturing-based solutions for preparation of elastomeric foam with broaden compressive stress plateau.

Mechanic models are developed for obtaining designs of foam cell units with enhanced elastic buckling. An experimental approach is taken to fabricate the foams based on direct ink writing technique. Experimental and simulation data are collected to assist understanding of our proposals and solutions.

A simple tetragonal structured elastomeric foam is proposed and fabricated by direct ink writing, in which its cell unit is theoretically designed by repeating every four filament layers. The foam exhibits a broader stress plateau, because of the pronounced elastic buckling under compressive loading as predicted by the authors’ mechanic modeling. A two-stage stress plateaus as observed in the foam, being attributed to the dual elastic buckling of the cell units along two lateral directions of the XY plane during compression.

Future work should incorporate more microscopic parameters to tune the elastomeric foam for mechanic performance testing on linear elastic deformation and densification of polymer matrix.

Additive manufacturing offers an alternative to fabricate elastomeric foam with controlled cell unit design and therefore mechanics. Our results comment on its broad space for development such superior cushioning or damping material in the fields of vibration and energy absorption.

This work has contributed to new knowledge on preparation of high performance elastomeric foam by providing a better understanding on its cell structure, being printed using direct ink writing machines.

From practical perspectives and to improve the working efficiency, trolley transportation and payload hoisting/lowering should be simultaneously controlled. Moreover, in practical crane applications, the transportation time is an important criterion for improving transportation efficiency. Based on these requirements, this paper aims to solve positioning and antiswing control problems and shorten the transportation time for underactuated varying-rope-length overhead cranes.

By choosing trolley acceleration and varying-rope-length acceleration as system inputs, the crane system dynamic model is converted into an equivalent model without linearizing/approximating. Then, based on the converted model and system state constraints, a time-optimal problem is formulated. Further, the original problem is converted into an optimization problem with algebraic constraints which can be conveniently solved. Finally, by solving the optimization problem, the optimal trajectories of system states, including displacements, velocities and accelerations, are obtained.

This paper first provides a nonlinear time-optimal trajectory planner for varying-rope-length overhead cranes, which achieves accurate and fast trolley positioning and eliminates payload residual swings. Meanwhile, all system states satisfy the given constraints during the entire process. Hardware experimental results show that the proposed time-optimal planner is effective and has better performance compared with existing methods.

This paper proposes a time-optimal trajectory planner for overhead crane systems with hoisting/lowering motion. The proposed planner achieves fast trolley positioning and eliminates payload residual swing with all the system states being constrained within given scopes. The planner is presented based on the original nonlinear system dynamics without linearization/approximation.

Equally weighted factors and initial data from behavioural sequences are used for calculating the degree of grey incidence in Deng’s grey incidence analysis. However, certain grey information cannot be directly obtained, and the correlation coefficients of each sequence at different times are of different importance to the system. The purpose of this paper is to propose an improved grey incidence model with new grey incidence coefficients and weighted degree of grey incidence. Some grey information can be obtained more easily by using the grey transformation sequences, and the maximum entropy method is used to calculate the weights of new grey incidence coefficients, so the new degree of grey incidence was distinguished more effectively by the proposed model.

New grey incidence coefficients are defined using transformation sequences of the initial data. To overcome the shortcomings arising from the use of equal weights, the maximum entropy method is proposed for determining the weights of the grey incidence coefficients. The resulting model optimises the classical models and evaluates the influencing factors more effectively. The effectiveness of the model was verified by a numerical example. Furthermore, the model was used for analysing the main influencing factors of the tertiary industry in China.

The proposed model optimises the classical models, and the application example shows that urbanisation has the greatest effect on employment in the tertiary sector.

An improved grey incidence model is proposed that improves the grey incidence coefficients and their weights, and has better performance than the classical models. The model was successfully used in the analysis of the influence factors of the tertiary industry in China. The results indicate that the model can reflect the significance of incidence coefficients at different time points; therefore, their fluctuation can be effectively controlled.