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In the cold rolling process, friction coefficient, oil film thickness and other factors vary dramatically with the change in the rolling speed, which seriously affects the strip thickness deviation. This paper aims to improve the strip control precision with the forecast roll gap model based on CF-PSO-SVM approach in the rolling process.

In this paper, a novel forecasting model of the roll gap based on support vector machine (SVM) optimized by particle swarm optimization with compression factor (CF-PSO) is proposed. Based on lots of online data, the roll gap models regressed by PSO-SVM, genetic algorithm (GA)-SVM and CF-PSO-SVM are obtained and verified through evaluating the performances with the decision coefficient (R²), mean absolute error and root mean square error. In addition, with the good forecasting performances of CF-PSO-SVM, a roll gap compensation model is studied.

The results indicate that the proposed CF-PSO-SVM has excellent learning regression ability compared with other optimization algorithms. Meanwhile, a roll gap compensation model based on the rolling speed and plastic coefficient is obtained, which has been proved validated in product.

In this paper, the SVM algorithm is combined with traditional rolling technology to solve the problems in actual production, which has great supporting significance for the improvement of production efficiency.

Partial alignment for 3 D point sets is a challenging problem for laser calibration and robot calibration due to the unbalance of data sets, especially when the overlap of data sets is low. Geometric features can promote the accuracy of alignment. However, the corresponding feature extraction methods are time consuming. The purpose of this paper is to find a framework for partial alignment by an adaptive trimmed strategy.

First, the authors propose an adaptive trimmed strategy based on point feature histograms (PFH) coding. Second, they obtain an initial transformation based on this partition, which improves the accuracy of the normal direction weighted trimmed iterative closest point (ICP) method. Third, they conduct a series of GPU parallel implementations for time efficiency.

The initial partition based on PFH feature improves the accuracy of the partial registration significantly. Moreover, the parallel GPU algorithms accelerate the alignment process.

This study is applicable to rigid transformation so far. It could be extended to non-rigid transformation.

In practice, point set alignment for calibration is a technique widely used in the fields of aircraft assembly, industry examination, simultaneous localization and mapping and surgery navigation.

Point set calibration is a building block in the field of intelligent manufacturing.

The contributions are as follows: first, the authors introduce a novel coarse alignment as an initial calibration by PFH descriptor similarity, which can be viewed as a coarse trimmed process by partitioning the data to the almost overlap part and the rest part; second, they reduce the computation time by GPU parallel coding during the acquisition of feature descriptor; finally, they use the weighted trimmed ICP method to refine the transformation.

This study chooses the content perception perspective to develop a theoretical model portraying the psychological activities of Web surfers exposed to content Web sites. After collecting 549 empirical observations in a controlled lab environment, tests the theoretical relationships by using the structural equation modelling (SEM) technique. The results strongly indicate that effective content perceptual dimensions can help content Web surfers to develop positive attitudes toward content sites, which in turn induce favorable behavioral outcomes such as frequent site usage and loyalty. Such a proposed theoretical model not only has the potential to enrich the theoretical underpinning of Internet studies but also presents a practical framework to guide content strategy formulations for the online content industry. Detailed implications for both managerial research and practice are discussed.

Lots of successful space missions require that the maneuvering spacecraft can reach the target spacecraft. Therefore, research on relative reachable domain (RRD) in target orbit for maneuvering spacecraft is particularly important and is currently a hot-debated topic in the field of aerospace. This paper aims at analyzing and simulating the RRD in target orbit for maneuvering spacecrafts with a single fixed-magnitude impulse and continuous thrust, respectively, to provide a basis for analyzing the feasibility of spacecraft maneuvering missions and improving the design efficiency of spacecraft maneuvering missions.

Based on the kinematics model of relative motion, RRD in target orbit for maneuvering spacecraft with a single fixed-magnitude impulse can be calculated via analyzing the relationship between orbital elements, position vector and velocity vector of spacecrafts, and relevant studies are introduced to compare simulation results for the same case and validate the method proposed in the paper. With analysis of the dynamic model of relative motion, the calculation of RRD in target orbit for maneuvering spacecraft with continuous thrust can be transformed as the solution of the optimal control problem, and example emulations are carried out to validate the method.

For the case with a single fixed-magnitude impulse, simulation results show preliminarily that the method is in agreement with the method in Ref. (Wen et al., 2016), which treats the same case and thus is plausibly correct and feasible. For the case with continuous thrust, analysis and simulation results confirm the validity of the proposed method. The methods based on relative motion in this paper can efficiently determining the RRD in target orbit for maneuvering spacecraft.

Both theoretical analyses and simulation results indicate that the method proposed in this paper is comparatively simple but efficient for determine the RRD in target orbit for maneuvering spacecraft swiftly and precisely.

The purpose of this paper is to examine the performance of 19 Malaysian Real Estate Investment Trusts (M-REITs) over the period 1999 to 2014, following the implementation of dividend tax reforms announced in the 2007, 2009 and 2012 budgets.

Sharpe index, Treynor index and Jensen α are utilized to compare the performance of M-REITs against a newly developed tax-adjusted value-weighted M-REITs index, equity market, property sector and three month Malaysia Treasury Bills (T-Bills). The calculation of M-REITs returns has been adjusted to take into account the dividend tax reforms which have never been considered in previous studies.

Most M-REITs outperform the tax-adjusted value-weighted REITs index, equity market, property sector and three month T-Bills. Property sector performs worst during those periods. Some of the M-REITs have a higher standard deviation than the equity market and the tax-adjusted value-weighted M-REITs index. Most M-REITs have a lower total risk than the property sector. Further analysis shows that before (after) the tax reforms, most M-REITs underperform (outperform) the other sectors. The introduction of the tax reforms benefits both REITs and investors. A significant positive Jensen α for some M-REITs indicates that fund managers are able to time the market or to select undervalued assets.

Findings of the study would enable investors to evaluate the performance of all REITs in comparison to other financial assets during the period of study for better investment decision making. A more accurate assessment on REITs performance that take into account the tax reforms, is available for investors and fund managers to decide on the investment mix to be included in their portfolio. Moreover, fund managers’ performance can be assessed whether they perform better or worse than the equity market, property sector and three month T-Bills.

This study contributes to the scant literature on dividend tax reforms and their implication toward REITs performance. It is the first study to thoroughly assess the returns of REITs by taking into account the changes on dividend tax rates announced in the 2007, 2009 and 2012 budgets.

Retail property is an important property investment sector. The purpose of this paper is to assess the importance of retail property type, size and region in Australian retail property and the strategic role of direct retail property and retail listed property trusts (LPTs) in a mixed‐asset portfolio.

This paper analyses the performance of retail property in Australia over 1995‐2005 for both direct and indirect retail property. Risk‐adjusted performance analysis is used to assess the added value of retail property in a mixed‐asset portfolio, with the portfolio diversification benefits of retail property also assessed.

The paper finds that retail property and retail LPTs have delivered substantial risk‐adjusted returns and portfolio diversification benefits over 1995‐2005. The retail property sub‐sectors of retail property type, size and region have different performance characteristics; particularly highlighting the substantial role of geographic diversification as the most effective portfolio diversification strategy for retail property investors. Direct retail property and retail LPTs are also identified as having different performance characteristics and each contributing substantially to an institutional property investment strategy.

Previous retail research has been at an “overall” Australian retail property level. This paper rigorously assesses retail property at a retail sub‐sector level regarding retail property type, size and location. This level of analysis enables more informed and practical investment decision‐making regarding the role of retail property in a mixed‐asset portfolio for both direct and indirect retail property as part of an institutional property investment strategy.

The paper aims to fabricate an α-tricalcium phosphate (TCP) scaffold with an interconnected porous structure via selective laser sintering (SLS). To inhibit the phase transformation from β- to α-TCP in fabrication process of porous scaffolds, a small amount (1 weight per cent) of poly (L-lactic acid) (PLLA) is added into β-TCP powder to introduce the transient liquid phase.

The paper opted for the transient liquid phase of melting PLLA to decrease the sintering temperature in SLS. Meanwhile, the densification of β-TCP is enhanced with a combined effect of the capillary force caused by melting PLLA and the surface energy of β-TCP particles. Moreover, the PLLA will gradually decompose and completely disappear with laser irradiation.

The testing results show the addition of PLLA enables the scaffolds to achieve a higher β-TCP content of 77 ± 1.49 weight per cent compared with the scaffold sintered from β-TCP powder (60 ± 1.65 weight per cent), when the laser energy density is 0.4 J/mm2. The paper provides the mechanism of PLLA inhibition on the phase transformation from β- to α-TCP. And the optimum sintering parameters are obtained based on experimental results, which are used to prepare a TCP scaffold with an interconnected porous structure via SLS.

This paper shows that the laser energy density is an important sintering parameter that can provide the means to control the micro-porous structure of the scaffold. If the laser energy density is too low, the densification is not enough. On the other hand, if the laser energy density is too high, the microcracks are observed which are attributed to the volume expansion during the phase transformation from β- to α-TCP. Therefore, the laser energy density must be optimized.

The paper provides a feasible method for fabricating TCP artificial bone scaffold with good biological and mechanical properties.

This paper aims to comprehensively review the preparation methods of superhydrophobic surfaces (SHPS) for corrosion protection of Mg alloy in recent years.

The preparation methods, wettability and corrosion resistance of SHPS on Mg alloy in the past three years are systematically described in this paper.

Two types of SHPS, including single-layer and multilayer coatings for corrosion protection of Mg alloy are summarized. Preparing multilayered coatings with multifunction is the current trend in developing SHPS on Mg alloy.

This paper reviewed the preparation methods and corrosion resistance of SHPS on Mg alloys. It provides a valuable reference for researchers to develop highly durable SHPS with excellent corrosion resistance for Mg alloys.

The purpose of the study was to investigate both the positive and negative effects of workplace loneliness on innovative behavior. By applying the unified theory on contingencies of self-worth, the study aimed to integrate these effects into a single framework, thereby confirming the presence of the double-edged sword effect of workplace loneliness on innovative behavior.

A survey was conducted among enterprises across China, involving 246 employees. Hierarchical regression analysis was utilized to test the moderating hypotheses. Additionally, the mediating effects and the moderated mediation effects were further explored using the bootstrapping method.

The results indicated that workplace loneliness positively influenced innovative behavior through the desire to prove ability, with the promotion regulatory focus enhancing this relationship. Conversely, workplace loneliness negatively influenced innovative behavior through self-handicapping, with the prevention regulatory focus intensifying this relationship.

The findings revealed that workplace loneliness exerts a double-edged effect on innovative behavior. Lonely employees can enhance their sense of self-worth by engaging in domain switching, thereby alleviating feelings of loneliness.

The research confirmed a novel perspective: workplace loneliness can promote innovative behavior by influencing employees’ desire to prove ability. It also revealed the double-edged sword effect of workplace loneliness on innovative behavior. Based on these findings, employees experiencing loneliness can enhance their self-worth and alleviate feelings of loneliness through domain switching.