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Steel-reinforced concrete-filled steel tubular (SRCFST) columns have been increasingly popular in engineering practice for the columns' excellent seismic and fire performance. Significant design progress guidance has been made through continuous numerical and experimental research in recent years. This paper tested and analysed the residual loading capacity of SRCFST columns under axial loading after experiencing non-uniform ISO-834 standard fire.

The experimental research covered the main parameter of heating conditions, 1-side and 2-side fire, through two specimens. Two specimens were heated and loaded simultaneously in the furnace for 240 min. After cooling, the columns were moved to the hydraulic loading system and loaded to failure to determine the columns' residual capacity.

The experimental results indicated that the non-uniform heating area plays an essential role in the overall performance of SRCFST columns, the increasing heating area of columns results in lower residual loading capacity and stiffness. The SRCFST columns still had a high loading capacity after heating and loading in the fire.

The comparison of experimental data against design results showed that the design method generated a 16% safety margin for S2H4 and a 39% safety margin for S1H4.

Word‐of‐mouth (WOM) has been found to significantly influence consumers' decision making. Much attention has been paid to the effect of WOM characteristics such as the number of postings, the dispersion of online conversations, the reputation of the reviewers, and the review quality on product sales. Little research, however, has examined the interaction process of online reviews. The purpose of this paper is to investigate the consumers' product attitude formation process in online WOM. Three research questions will be addressed in this paper, i.e. the effect of prior responses on the following repliers' product attitude, the negativity effect and the role of main messages in shaping consumers' product attitude formation process.

The product attitude formation process of online WOM is investigated using the data of product reviews (main messages) and their corresponding responses. The paper collected 26 product reviews from various web sites and kept the first 40‐50 responses for each review, which resulted in 26 main messages and 1,173 observations (i.e. responses) in total. A hierarchical Bayesian ordinal choice model is then specified and estimated with the Markov Chain Monte Carlo method to address the research questions and to capture the main message heterogeneity.

The paper finds that the impact of prior responses (e.g. the proportion of positive and negative responses) on the product attitudes of the following responses differs significantly across products. This heterogeneity can be well explained by the characteristics of the main messages at the second‐level specification. Thereby, factors that influence consumers' product attitudes in the interaction process of online WOM include prior responses and main message characteristics. Another interesting finding is that positive responses have larger impacts on product attitudes than negative ones.

This research contributes to both academic research and the firms' online WOM management. Theoretically, this research is the first attempt to examine the formation process of attitudes toward new products in online communications. This research contributes by modeling how the dynamic process of online WOM influences new product attitudes. Furthermore, inconsistent with the “negativity effect” proposed by researchers (e.g. Skowronski and Carlston), the paper finds that positive responses matter more than negative ones in online communications. In addition, the way the paper configures the data for online communications is innovative and provides a perspective to quantitatively model the communication process. Managerially, this research provides implications for firms to intervene in the online communication process and influence consumer attitude of new products.

Previous researches on credit scoring mainly focussed on static modeling on panel sample data set in a certain period of time, and did not pay enough attention on dynamic incremental modeling. The purpose of this paper is to address the integration of branch and bound algorithm with incremental support vector machine (SVM) ensemble to make dynamic modeling of credit scoring.

This new model hybridizes support vectors of old data with incremental financial data of corporate in the process of dynamic ensemble modeling based on bagged SVM. In the incremental stage, multiple base SVM models are dynamically adjusted according to bagged new updated information for credit scoring. These updated base models are further combined to generate a dynamic credit scoring. In the empirical experiment, the new method was compared with the traditional model of non-incremental SVM ensemble for credit scoring.

The results show that the new model is able to continuously and dynamically adjust credit scoring according to corporate incremental information, which helps produce better evaluation ability than the traditional model.

This research pioneered on dynamic modeling for credit scoring with incremental SVM ensemble. As time pasts, new incremental samples will be combined with support vectors of old samples to construct SVM ensemble credit scoring model. The incremental model will continuously adjust itself to keep good evaluation performance.

Because natural resource utilization is a predictor of sustainable development, an evaluation of the efficiency of resource utilization is critical for assessing developmental potentiality. The purpose of this paper is to apply three-dimensional (3D) ecological footprint theory to assess the effects of production and consumption on ecological systems in Hefei, China.

Using data for Hefei for the period 2005-2014, an ecological footprint model (EFM) was developed to calculate the area’s ecological footprint (EF), ecological carrying (EC) capacity and obtain two indices, namely, footprint depth and size. The relationship between economic development and natural resource utilization was subsequently evaluated based on the calculated ecological deficit and the EF demand per Renminbi 10,000 of gross domestic product (GDP).

Over the last decade, Hefei’s EF per capita evidenced a 9.87 percent growth rate, increasing from 1.16 hm²/person in 2005 to 2.70 hm²/person in 2014. EC capacity per capita increased from 0.21 hm²/person in 2005 to 0.36 hm²/person in 2014, evidencing a gradually increasing trend at an average annual growth rate of 6.24 percent. Thus, between 2005 and 2014, the ecological deficit increased annually by three times. The amplification of footprint depth significantly exceeded that of footprint size. Between 2005 and 2014, Hefei’s EF per capita Renminbi 10,000 of GDP decreased annually by 4.68 percent. Thus, energy consumption in Hefei exceeded the natural regeneration capacity of energy resources, with excessive development and resource utilization impacting on the regional ecological system.

The application of a 3D EFM sheds light on natural resource utilization within regional development. Moreover, footprint depth and size are significant predictors of the impacts of natural resource utilization. These findings will also benefit other countries or cities.

This is one of the first empirical studies to apply a 3D EFM to evaluate the relationship between natural resource utilization and economic development. Adopting a sustainable development framework, it provides insights into the effects of natural resource utilization in relation to the balance between the natural ecological system and economic development. This has far-reaching implications beyond Hefei and China.

This study aims to identify an antecedent that hinders knowledge sharing, namely, the perceived climate of Cha-xu. Based on the social exchange perspective, the authors propose a theoretical model that links the perceived climate of Cha-xu to employee knowledge sharing. This model focuses on the mediating role of two types of trust (vertical and horizontal trust) and the moderating role of task interdependence in influencing the mediation.

Using a sample of 509 Chinese employees, this study carried out a survey on an online platform. This study developed a structural equation model and tested the moderated mediation hypothesis by using Mplus 8.0.

The results showed that two types of trust act as mediators in the relationship between the perceived climate of Cha-xu and knowledge-sharing processes. The mediating effect of horizontal trust is stronger. Most significantly, findings show that this mediated relationship is contingent on the level of task interdependence.

This paper provides evidence for distinguishing vertical trust and horizontal trust in the field of knowledge management. From a managerial perspective, this study identifies traditional cultural factors for hindering knowledge-sharing processes within Chinese organizations.

As the concentration of environmental samples was generally very low and existing analytical instruments had limited sensitivity, developing mini pre-treatment systems for effectively concentrating the components was very important and necessary. The purposed of this paper is to develop mini pretreatment system integrated with micro pre-concentrator and micro GC column.

In this work, a mini pre-treatment system integrated with a micro pre-concentrator and a micro gas chromatograph (GC) column was proposed. The micro pre-concentrator filled with single-walled carbon nanotubes as adsorbent materials was able to effectively concentrate the trace environmental sample, which dramatically improved the response of detectors. In addition, instead of conventional columns, micro GC columns were able to effectively separate gas mixtures, which are able to overcome low resolution and poor anti-interference ability of portable instruments.

The results demonstrated that the proposed pre-treatment system was able to concentrate the trace sample with a concentration factor of 15 and effectively separate the gas mixtures with a resolution over 1.5.

A mini pre-treatment system integrated with a micro pre-concentrator and a micro GC column was proposed.

Imitation learning is a powerful tool for planning the trajectory of robotic end-effectors in Cartesian space. Present methods can adapt the trajectory to the obstacle; however, the solutions may not always satisfy users, whereas it is hard for a nonexpert user to teach the robot to avoid obstacles in time as he/she wishes through demonstrations. This paper aims to address the above problem by proposing an approach that combines human supervision with the kernelized movement primitives (KMP) model.

This approach first extracts the reference database used to train KMP from demonstrations by using Gaussian mixture model and Gaussian mixture regression. Subsequently, KMP is used to modulate the trajectory of robotic end-effectors in real time based on feedback from its interaction with humans to avoid obstacles, which benefits from a novel reference database update strategy. The user can test different obstacle avoidance trajectories in the current task until a satisfactory solution is found.

Experiments performed with the KUKA cobot for obstacle avoidance show that this approach can adapt the trajectories of the robotic end-effector to the user’s wishes in real time, including trajectories that the robot has already passed and has not yet passed. Simulation comparisons also show that it exhibits better performance than KMP with the original reference database update strategy.

An interactive learning approach based on KMP is proposed and verified, which not only enables users to plan the trajectory of robotic end-effectors for obstacle avoidance more conveniently and efficiently but also provides an effective idea for accomplishing interactive learning tasks under constraints.

Understandings of house prices and their interrelationships have undoubtedly drawn a great amount of attention from various market participants. This study aims to investigate the monthly newly-built residential house price indices of seventy Chinese cities during a 10-year period spanning January 2011–December 2020 for understandings of issues related to their interdependence and synchronizations.

Analysis here is facilitated through network analysis together with topological and hierarchical characterizations of price comovements.

This study determines eight sectoral groups of cities whose house price indices are directly connected and the price synchronization within each group is higher than that at the national level, although each shows rather idiosyncratic patterns. Degrees of house price comovements are generally lower starting from 2018 at the national level and for the eight sectoral groups. Similarly, this study finds that the synchronization intensity associated with the house price index of each city generally switches to a lower level starting from early 2019.

Results here should be of use to policy design and analysis aiming at housing market evaluations and monitoring.

Energy consumption is a fundamental concern in wireless multimedia sensor networks, even more than that in traditional wireless sensor networks. In fact, sensors are battery‐constrained devices, while multimedia applications, which require higher transmission rates and more extensive processing capacity, produce large quantities of data. The purpose of this paper is to propose a method which could save multimedia nodes' energy during their sleeping and transmitting phases and effectively bring down energy consumption.

Based on the location and direction angle of nodes, areas of the overlapping sensing region between adjacent nodes could be calculated and a sleeping strategy is carried out to reduce energy consumption of inactive nodes. Moreover, an improved image comparison and block transmission methods by utilizing the sequence similar detection arithmetic theory is brought up as well to further save the node's energy.

With the help of the mobile nodes and by dividing the network into grids, sensing direction of multimedia node as well as the area of the overlapping sensing region could be obtained which provide a basis for the sleeping strategy. Furthermore, energy consumption on transmission is also reduced by only transmitting the unmatched blocks. Simulation results show that this method obtains satisfactory performance on prolonging the networks' lifetime.

This paper is of value in presenting an effective energy‐saving strategy for wireless multimedia sensor networks.

In any time and space and under any circumstance, we find peasants are never passive actors in their livelihoods and rural development. Instead, they always create space for manoeuvre in order to make changes. This chapter analyses the innovative actions taken by the majority of rural inhabitants in rural areas during the overwhelming modernization process, so as to affirm that peasants are the main actors of rural development. It is they who have shaped the transformation of rural societies and the history. Through the analysis, this chapter concludes that rural development is not an objective, a blueprint nor a design. It is not the to-be-developed rear field in modernization. It is not the babysitter for cities, nor a rehearsal place for bureaucrats to testify their random thoughts. Rural development is what peasants do. The path they have chosen reveals scenery so different from modernization. If we regard development as a social change, or a cross with influential meanings, we could understand rural development as peasants’ victories over their predicament. Villages accommodate not only peasants, but without peasants villages would surely vanish. In this sense, the most important part in rural development or rural change is peasants – their conditions and their feelings.