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The purpose of this study is to explore factors correlated with police cadets' perceived commitment to the police profession – whether or not personal attitudes and demographic characteristics can make a difference.

The study used two-year longitudinal data collected from a population of 207 Chinese police cadets. Survey research based on pre-designed instruments was employed to collect the data.

The results from panel data analysis found that personal interest in adolescence and attitudes toward styles of policing were significant predictors. Specifically, attitudes toward community policing were positively related to the cadets' commitment to the police profession.

Police occupational commitment is essential since the commitment is closely linked to voluntary retention and organizational effectiveness. However, limited empirical research has been available regarding the factors associated with officers' identification and commitment to the occupation. This study provides insight into police officer training and recruitment and offers suggestions for future research.

The purpose of this study is to examine the effect and duration of supervised field training on police cadets' worldview of police work in China.

The four-wave longitudinal data were collected from graduate students who were pursuing their master's degree in a national Chinese police university from 2016 to 2018. Independent variables including demographic characteristics and knowledge along with experience gained from the internship were used to explain police cadets' attitudes toward police work. Ordinary least square (OLS) regression models were used in the current study.

Findings derived from multiple regression analyses suggest that police cadets' attitudes toward police work are conducive to the “shock” of the real-world experience after three-month field training. However, the effect of the field training on police cadets' attitudes toward police work is temporary, not enduring.

The data for this study were collected from one national police university, and the findings reported here may not be generalized.

Police field training is important for cadets to develop positive view of police work. It provides practical knowledge for police training and socializes cadets before entering into the law enforcement filed, avoiding the financial cost of resignation. However, the influence of field training is temporal. Hence, it is more appropriate for police administrators to arrange police cadets' field training close to their graduation date, the third year of their college education.

This study can be considered as an extension of relevant research on law-enforcement-related field training reported in the United States. However, it goes beyond the existing literature by using longitudinal data to answer a long-overdue question: Does supervised field training change the worldview of cadets concerning police work?

Market integration in China is still progressing, while the border effects of trade among regions still exist. The question of whether eliminating or weakening regional bias can promote of China's agricultural trade still remains an important issue. This paper analyzes the impact of regional bias on China's agricultural trade.

This paper constructs a pure exchange computable general equilibrium model of nine regions and three sectors, and analyzes the impact of regional bias on China's regional agricultural trade; Comparing the differences of regional bias on China's inter-regional and external agricultural trade, the paper especially analyzes the impact of the agricultural imports and exports in eight regions of China.

The results show that regional bias has had substantial impacts on China's agricultural trade. Elimination of regional bias would therefore increase China's agricultural exports and imports by factors of 1.32 and 1.63, respectively while its agricultural trade deficit would increase by 84%. Inter-regional agricultural trade in China would increase by 3.53 times. With the elimination of regional bias, the Northern coastal, Central and Northwestern regions would have the largest increase in inter-regional agricultural trade. Unlike the Northern coastal region, inter-regional agricultural import in the Central and Northwestern regions tends to be greater than inter-regional agricultural exports.

This paper thus aims to fill existing gap in investigating the impacts of regional bias on China's agricultural trade. Firstly, the model proposed in this paper does not only consider the linkage between the agricultural and non-agricultural sectors, but also the inter-regional agricultural trade linkages of the different regions in China. Secondly, the authors decompose home bias into national and regional biases and assess how regional bias affects agricultural trade of the various regions of China.

This study aims to explore customers’ green hotel revisit behaviors, proposing the theory of repeat purchase behavior.

An empirical study is conducted through a questionnaire survey method, using personal interview survey approach in Bangladesh. In all, 401 usable data is collected from participants who have visited green hotels before. The following data are analyzed through partial least squares structural equation modeling (PLS-SEM) using Smart PLS 3.3.3.

Results of the study have raveled that habitual attachment and emotional attachment are significantly related to green hotel revisit intentions (behavioral intention) and revisiting a green hotel (actual behavior). The result also has uncovered that green hotel revisit intentions significantly impacted revisiting a green hotel. Moreover, the study results exert that green hotel revisit intentions partially mediate the relationship between habitual attachments, emotional attachment, and revisiting a green hotel.

The current study enriches green hospitality literature by uncovering the integrated effects of habitual attachment and emotional attachment on customers’ revisit intentions and behaviors in the green hotels’ context.

This study aims to extract an analytical model for five-phase fault-tolerant permanent-magnet vernier machines (FTPMVMs) based on the analytical solution of Maxwell’s equations, which has some advantages than the finite element model.

FTPMVMs enhance the torque density by combining the vernier characteristics and the fault-tolerant feature. The principle operation of FTPMVMs is discussed based on the magnetic field modulation due to both permanent magnets and armature current. The analytical solution of the magnetic vector potential in each sub-region is obtained based on the sub-domain technique.

According to the calculated magnetic vector potential, the magnetic flux density, torque, self- and mutual inductance and back-electromotive force are calculated. The FEM is used to validate the results obtained from the proposed analytic model.

Two-dimensional analytical method is used to obtain the electromagnetic model of FTPMVMs.

The purpose of this paper is to present a fast, economical and practical method for mathematical modeling of aerodynamic characteristics of rectangular wing in ground (WIG) effect.

Reynolds averaged Navier–Stokes (RANS) equations were converted to Bernoulli equation by reasonable assumptions. Also, Helmbold’s equation has been developed for calculation of the slope of wing lift coefficient in ground effect by defining equivalent aspect ratio (ARe). Comparison of present work results against the experimental results has shown good agreement.

A practical mathematical modeling with lower computational time and higher accuracy was presented for calculating aerodynamic characteristics of rectangular WIG effect. The relative error between the present work results and the experimental results was less than 8 per cent. Also, the accuracy of the proposed method was checked by comparing with the numerical methods. The comparison showed fairly good accuracy.

Aerodynamic surfaces in ground effect were used for reducing wetted surface and increasing speed in high-speed marine and novel aeronautical vehicles.

The proposed method is useful for investigation of aerodynamic performance of WIG vehicles and racing boats with aerodynamic surfaces in ground effect.

The proposed method has reduced the computational time significantly as compared to numerical simulation that allows conceptual design of the WIG crafts and is also economical.

In semi-analytical modeling of spoke-type permanent-magnet (PM) machines (STPMM), the saturation effect is usually neglected (i.e. iron parts are considered to be infinitely permeable) and the PM magnetization is assumed tangential (i.e. magnetization pattern is considered to be tangential-parallel). This paper aims to present an improved two-dimensional (2D) subdomain technique for STPMM with the PM magnetization orientation in quasi-Cartesian coordinates by using hyperbolic functions considering non-homogeneous Neumann boundary conditions (BCs) in non-periodic regions and by applying the interfaces conditions (ICs) in both directions (i.e. t- and θ edges ICs).

The polar coordinate system is transformed into a quasi-Cartesian coordinate system. The rotor and stator regions are divided into primary subdomains, and a partial differential equation (PDE) is assigned to each subdomain. In the PM region, the magnetization orientation is considered in the equations. By applying BCs, the general solution of the equations is determined, and by applying the ICs, the corresponding coefficients are determined.

Using the proposed coordinate system, the general solution of PDEs and their coefficients can mathematically be simplified. The magnetic field and non-intrinsic unbalanced magnetic forces (UMF) calculations have been performed for three different values of iron core relative permeability (200, 800 and ∞), as well as different magnetization orientation values (135 and 80 degrees). The semi-analytical model based on the subdomain technique is compared with those obtained by the 2D finite-element analysis (FEA). Results disclose that the PM magnetization angle can affect directly the performance characteristics of the STPMM.

A new model for prediction of electromagnetic performances in the STPMM takes into account magnetization direction, and soft magnetic material relative permeability in a pseudo-Cartesian coordinate system by using subdomain technique is presented.

There is some evidence that suggest a higher dietary total antioxidant capacity (DTAC) is associated with a lower risk of metabolic syndrome (MetS). Considering the conflicting results in this field, this paper aims to provide a comprehensive summary of studies on the association of DTAC and components of MetS.

A systematic review of articles indexed in PubMed, Scopus and Google Scholar, published from inception to September 2018, with defined keywords, was done. Duplicate or irrelevant reports were screened out and data were extracted through critical analysis. Finally, among the 353 articles, 19 articles met the inclusion criteria.

The included cohort studies revealed that higher DTAC was associated with reduced risk of MetS. Also, the association between DTAC and mortality risk of MetS was insignificant in these studies. The case–control studies showed high DTAC is inversely associated with MetS, its components and complications. The randomized controlled trials found that changes in DTAC were negatively correlated with oxidized low-density lipoprotein cholesterol and there was a positive association between DTAC and subjects’ weight and body mass index. Finally, results from the cross-sectional studies were inconsistence in this regard.

The assessed relationship between MetS or its components with DTAC is inconsistent in the included studies. Different sample size, dietary assessment tools, DTAC index values and geographical location may justify the observed inconsistencies. It seems that further studies are needed to reveal more confident and reliable findings.

Bellows-type fluid viscous damper can be used to isolate micro vibration in high-precision satellites. The conventional model cannot describe hydraulic stiffness in the medium- and high-frequency domain of this damper. A simplified analytical model needs to be established to analyze hydraulic stiffness of the damping element in this damper.

In this paper, a bellows-type fluid viscous damper is researched, and a simplified model of the damping element in this damper is proposed. Based on this model, the hydraulic stiffness and damping of this damper in the medium- and high-frequency domains are studied, and a comparison is made between the analytical model and a finite element model to verify the analytical model.

The results show that when silicone oil has low viscosity, a model that considers the influence of the initial segment of the damping orifice is more reasonable. In the low-frequency domain, hydraulic stiffness increases quickly with frequency and remains stable when the frequency increases to a certain value; the stable stiffness can reach 106 N/m, which is much higher than the main stiffness. Excessive dynamic stiffness in the high-frequency domain will cause poor vibration isolation performance. Adding compensation bellows to the end of the original isolator may be an effective solution.

A model of the isolator containing the compensation bellows can be derived based on this analytical model. This research can also be used for dynamic modeling and vibration isolation performance analysis of a vibration isolation platform based on this bellows-type fluid viscous damper.

This paper proposed a simplified model of damping element in bellows-type fluid viscous damper, which can be used to analyze hydraulic stiffness in this damper and it was found that this damper showed stable hydraulic stiffness in the medium- and high-frequency domains.

This paper aims to investigate the atmospheric corrosion mechanism of structural materials to develop more advanced corrosion-control technologies and cost-reduction strategies. As a second phase in steels, the non-metallic oxide inclusions are considered to not only affect the mechanical properties of steel but also the corrosion resistance of steel. So, an important research goal in this paper is to investigate the indoor accelerated corrosion kinetics of Q450NQR1 weathering steel, analyzing the galvanic polarity of different inclusions in electrochemical corrosion microcell between the inclusion and steel matrix and then elucidating the influence mechanism of inclusions on corrosion resistance of weathering steel.

Two methods of inclusion modification are usually used to improve the properties of weathering steel: one is calcium treatment on aluminum killed steel and the other one is rare earth (RE) modification. Wet/dry cyclic immersion corrosion test field emission scanning electron microscopy (FE-SEM) metallographic optical microscope.

The indoor accelerated corrosion kinetics of Q450NQR1 weathering steel could be divided into two stages with different log (thickness loss, D)-log (time, t) fitting functions, and the effect of inclusions on the corrosion resistance of Q450NQR1 weathering steel was only reflected in the initial stages of corrosion. The inclusions of CaS in Ca-modified test steel and RE oxides and sulfides in RE-modified test steel were preferentially dissolved in acid media, slowing down the corrosion rate of steel matrix, but the non-metallic inclusion Al₂O₃ may accelerate the corrosion rate of the steel matrix as a form of differential aeration corrosion.

The effects of inclusions on corrosion resistance of Q450NQR1 weathering steel was investigated by dry–wet cycle immersion test and FE-SEM. The effect of inclusions on the corrosion resistance of Q450NQR1weathering steel was only reflected in the initial stages of corrosion. The inclusions of CaS in Ca-modified test steel and rare earth (RE) oxides and sulfides in RE-modified test steel were preferentially dissolved in acid media, slowing down the corrosion rate of steel matrix, but the non-metallic inclusion Al₂O₃ may accelerate corrosion rate of the steel matrix as a form of differential aeration corrosion.