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The purpose of this paper is to construct diverse granules and coverings derived from a semi‐equivalence class and then to reveal the relationships between granules and coverings and even relations, and to help one to study pansystems relations in a trans‐cross view.

Forms regarding semi‐equivalence classes as primitives, blocks or granules such as tolerance class, join class, meet class, optimist/pessimist selected compatible class, and tolerantly kernel class in an incomplete information system are defined and compared. Different approximations are also introduced. Furthermore, diverse coverings are also suggested.

A tolerance class of an object is proved to be the join of semi‐equivalence classes containing it, i.e. a result of acting union operation on some primitive classes. A compatibly kernel class of an object is a meet of semi‐equivalence classes including it, i.e. a result of acting intersection operation on some primitive classes. Related coverings can also be regarded as coverings derived from the covering consisting of primitive granules. Several necessary and/or sufficient conditions for a general covering to become a semi‐equivalence or complete covering are obtained. Meaningful property and relationship results are also exploited.

Constructing diverse granules naturally from an incomplete information system to form a different knowledge expression system looks promising for data mining in the information society. It widens the approach and schema.

The paper shows that the formation process of granules is natural, newly defined, and not similar and theoretic to those existing in a neighborhood system. The relationship between diverse granules and coverings is described by mathematical theorems in sufficient or necessary condition form.

This paper aims to present a novel scheme of multiple vanishing points (VPs) estimation and corresponding lanes identification.

The scheme proposed here includes two main stages: VPs estimation and lane identification. VPs estimation based on vanishing direction hypothesis and Bayesian posterior probability estimation in the image Hough space is a foremost contribution, and then VPs are estimated through an optimal objective function. In lane identification stage, the selected linear samples supervised by estimated VPs are clustered based on the gradient direction of linear features to separate lanes, and finally all the lanes are identified through an identification function.

The scheme and algorithms are tested on real data sets collected from an intelligent vehicle. It is more efficient and more accurate than recent similar methods for structured road, and especially multiple VPs identification and estimation of branch road can be achieved and lanes of branch road can be identified for complex scenarios based on Bayesian posterior probability verification framework. Experimental results demonstrate VPs, and lanes are practical for challenging structured and semi-structured complex road scenarios.

A Bayesian posterior probability verification framework is proposed to estimate multiple VPs and corresponding lanes for road scene understanding of structured or semi-structured road monocular images on intelligent vehicles.

Positioning is a key task in most field robotics applications but can be very challenging in GPS‐denied or high‐slip environments. The purpose of this paper is to describe a visual odometry strategy using only one camera in country roads.

This monocular odometery system uses as input only those images provided by a single camera mounted on the roof of the vehicle and the framework is composed of three main parts: image motion estimation, ego‐motion computation and visual odometry. The image motion is estimated based on a hyper‐complex wavelet phase‐derived optical flow field. The ego‐motion of the vehicle is computed by a blocked RANdom SAmple Consensus algorithm and a maximum likelihood estimator based on a 4‐degrees of freedom motion model. These as instantaneous ego‐motion measurements are used to update the vehicle trajectory according to a dead‐reckoning model and unscented Kalman filter.

The authors' proposed framework and algorithms are validated on videos from a real automotive platform. Furthermore, the recovered trajectory is superimposed onto a digital map, and the localization results from this method are compared to the ground truth measured with a GPS/INS joint system. These experimental results indicate that the framework and the algorithms are effective.

The effective framework and algorithms for visual odometry using only one camera in country roads are introduced in this paper.

This paper aims to provide a series of new methods for projecting a three-dimensional (3D) object onto a free-form surface. The projection algorithms presented can be divided into three types, namely, orthogonal, perspective and parallel projection.

For parametric surfaces, the computing strategy of the algorithm is to obtain an approximate solution by using a geometric algorithm, then improve the accuracy of the approximate solution using the Newton–Raphson iteration. For perspective projection and parallel projection on an implicit surface, the strategy replaces Newton–Raphson iteration by multi-segment tracing. The implementation takes two mesh objects as an example of calculating an image projected onto parametric and implicit surfaces. Moreover, a comparison is made for orthogonal projections with Hu’s and Liu’s methods.

The results show that the new method can solve the 3D objects projection problem in an effective manner. For orthogonal projection, the time taken by the new method is substantially less than that required for Hu’s method. The new method is also more accurate and faster than Liu’s approach, particularly when the 3D object has a large number of points.

The algorithms presented in this paper can be applied in many industrial applications such as computer aided design, computer graphics and computer vision.

State-owned firms play important roles in Chinese cross-border acquisition (CBA) activities. However, compared with private firms, state-owned firms have a lower likelihood of acquisition completion and take longer to complete a deal. This paper aims to determine why this phenomenon exists and how state-owned firms can overcome the constraints of their identity.

By integrating organizational learning theory with institutional theory, this paper attempts to answer the research questions from a legitimacy perspective. Employing Chinese CBA data from 1982 to 2014, the authors use a logit model and a random effects model to test the hypothesis.

The results show that a state-owned identity easily causes legitimacy concerns among host country regulatory agencies; thus, it may result in longer and more uncertain evaluation behaviors, which lead to a lower likelihood of CBA completion and a longer deal duration. Only experience with failed acquisitions can increase CBA completion probability. Furthermore, in very complex decision-making environments, such as that surrounding deal duration, only specific types of experience (i.e. experience of failed international acquisitions) can trigger learning behavior, whereas general experience (i.e. failed acquisition experience) has little influence. Favorable bilateral relationships may not improve the completion rate and efficiency of state-owned firms, but high-quality host country institutions lead to a higher likelihood of CBA completion among state-owned firms; however, this may be not conducive to decreasing the time needed to complete an acquisition deal.

First, by discussing the completion rate and duration of CBAs conducted by state-owned firms and analyzing the factors that influence them, this paper enriches and develops the theory of organizational overseas mergers and acquisitions (M&As). Second, by adopting a legitimacy perspective and integrating institutional theory, the authors theorize how state-owned status influences firms’ M&A completion rate and time and test the hypotheses empirically; thus, this paper improves and deepens institutional theory. Third, by discussing how different types of experience (i.e. successful experience vs failed acquisition experience) influence the acquisition completion rate and duration and how general experience and specific types of experience affect these two dependent variables differently, this paper explains how state-owned firms can learn effectively from experience, contributing to organizational learning theory.

Airports are booming in China, to enlarge their capacities and stimulate economic development. Large-span spatial steel structures are commonly used in the terminal buildings of airport projects. Their advantages include prefabrication, strength, usability, adaptability and aesthetic quality. To manage large-span spatial steel structure projects, building information modeling (BIM) is recommended. Although there are plenty of studies on BIM application in steel structure projects, it is still rare to apply BIM to optimize the schedule and cost of steel structures, especially for airport projects.

This paper aims to develop a framework in which BIM and a time-cost optimization model are integrated to optimize construction costs and the duration of large-span spatial steel structure projects. A real case study was conducted to verify the feasibility of the BIM-based time-cost optimization model in an airport terminal building, which was built with a large-span spatial steel structure.

The results preliminarily support the reliability of the proposed BIM-based time-cost optimization model. The BIM-based time-cost optimization model will benefit construction planning for professionals and enrich relevant research on the application of BIM in large-span spatial steel structure projects.

The steel structure is difficult to control budgets and progress. This paper is expected to be adopted for optimizing the time and cost plans for projects involving steel structures in airport terminal buildings.

This study provides real-world evidence for the relationship between strategic communication from a global/multinational perspective and the effectiveness of corporate message strategies in the context of environment risk communication. Among sustainability issues, particulate matter (PM) air pollution has threatened the health and social wellbeing of citizens in many countries. The purpose of this paper is to apply the message framing and attribution theories in the context of sustainability communication to determine the effects of risk message characteristics on publics’ risk responses.

Using a 2 (message frame: gain vs loss) × 2 (attribution type: internal vs external) × 2 (country: China vs South Korea) between-subjects experimental design, the study examines the message framing strategies' on publics' risk responses (i.e. risk perception, risk responsibility attribution held toward another country and sustainable behavioral intention for risk prevention).

Findings include (1) main effects of message characteristics on participants’ risk responses; (2) the impact of country difference on participants’ differential risk responses and (3) three-way interactions on how risk message framing, risk threats type and country difference jointly affect not only participants’ risk perception and risk responsibility attribution but also their sustainable behavioral intention to prevent PM.

Although this study used young–adult samples in China and South Korea, the study advances the theory building in strategic environmental risk communication by emphasizing a global/multinational perspective in investigating differences among at-risk publics threatened by large-scale environmental risks.

The study's findings provide evidence-based implications such as how government agencies can enhance the environmental risk message strategy so that it induces more desired risk communication outcomes among at-risk publics. Insights from our study offer practical recommendations on which message feature is relatively more impactful in increasing intention for prosocial behavioral changes.

This study on all measured risk responses reveals important differences between at-risk young publics in China and South Korea and how they respond differently to a shared environmental risk such as PM. The study's findings provide new evidence that media coverage of global environmental issues needs to be studied at the national level, and cross-cultural comparisons are imperative to understand publics’ responses to different news strategies. Thus, this study offers implications for practitioners to understand and apply appropriate strategies to publics in a social way across different countries so as to tailor risk communication messaging.

This study offers new insights to help connect message framing effects with communication management practice at the multi-national level, providing recommendations for government communication practitioners regarding which PM message features are more likely to be effective in forming proper risk perception and motivate sustainable actions among at-risk publics in different countries.

The use of public engagement (PE) has been encouraged by the Hong Kong government in recent years, with the construction industry under particular pressure to employ it. However, society as a whole has been suffering as a result of various levels of discontent and conflict in many construction development projects. The logical paths to analyze public need and resolve conflict in the PE process are vague. Value methodology (VM), a logical method, is thus proposed as an initial framework to support PE activities in construction projects. The purpose of this paper is to enhance PE performance for the complicated construction development projects with the application of VM principles.

Based on an extensive literature review, PE logical team process factors and PE outcomes were identified. A questionnaire survey was conducted to investigate the relationships between the logical PE team decision-making process (VM application in the logical process and team behaviors) and final PE outcomes.

The results showed that the PE team process with the application of VM, especially information and analysis phases, influenced PE outcomes positively. Conflict (both destructive conflict and constructive conflict) influenced PE outcomes in different directions.

It is recommended that the information and analysis phases of VM are applied to PE process in order to achieve consensus, cultivate team spirit, improve project performance, and enhance organizational reputation.

This paper innovatively proposes the application of VM into the PE team process in order to analyze the project logically and subsequently improve holistic PE project performance and finally promote social cohesion.

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.