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Planning for underground spaces has become an effective way to use central areas in cities given the steady economic growth in China. The development of underground spaces in mountainous cities has satisfied the needs of the diversification of the city commercial areas and pedestrian movement. Safety issues exist because these underground spaces were originally used for civil air defense. This study was based on the underground commercial street in Chongqing, which is a typical mountainous city. Based on the results of combined fieldwork and survey, this paper summarized current safety issues, which include the not-fully-open exit, the imbalanced exit location, blocked evacuation routes, and the poor awareness of the potential safety issues. This paper proposed a framework of the safety factors for the underground space and synopsized prevention strategies that are specific to potential disasters in the underground environment. The framework comprises ensuring that the exits are fully open, the underground corridors are kept unblocked, the open space on the street is increased for disaster prevention, and equipment security is maintained and managed. At last, This paper summarized disaster prevention strategies, which include ensuring unimpeded exits, balancing the locations of the exits, avoiding blocks, increasing the disaster prevention square area in the underground space, maintaining and managing the security of the equipment.

The purpose of this paper is to describe a simulation and experimental research concerning the effect of recess depth on the lubrication performance of a hydrostatic thrust bearing by constant rate flow.

The computational fluid dynamics and finite volume method have been used to compute the lubrication characteristics of an annular recess hydrostatic thrust bearing with different recess depths. The performances are oil recess pressure, oil recess temperature and oil film velocity. The recess depth has been optimized. A test rig is established for testing the pressure field of the structure of hydrostatic thrust bearing after recess depth optimization, and experimental results show that experimental data are basically identical with the simulation results, which demonstrates the validity of the proposed numerical simulation method.

The results demonstrate that the oil film temperature decreases and the oil film pressure first increases and then decreases with an increase in the recess depth, but oil film velocity is constant. To sum up comprehensive lubrication performance, the recess depth of 3.5 mm is its optimal value for the annular recess hydrostatic thrust bearing.

The computed results indicate that to get an improved performance from a constant flow hydrostatic thrust bearing, a proper selection of the recess depth is essential.

Based on affective events theory, this research attempted to investigate how negative gossip about organizational change drives employees to experience negative emotions and direct their aggression toward customers.

We conducted a scenario-based experiment (Study 1) and a multiwave field survey (Study 2) to test our hypotheses.

The results show that (1) negative emotions mediate the relationship between change-related negative gossip and displaced aggression toward customers; (2) perceived organizational constraints strengthen the relationship between change-related negative gossip and negative emotions; (3) future work self-salience weakens the relationship between change-related negative gossip and negative emotions; and (4) change-related negative gossip has a strengthened (weakened) indirect effect on displaced aggression via negative emotions when employees have high perceived organizational constraints (future work self-salience).

The study expands research on organizational change and displaced aggression and provides practical implications for managing organizational change.

This paper aims to develop a novel type of bionic underwater robot (BUR) with multi-flexible caudal fins. With the coordinate movement of multi-caudal fins, BUR will combine the undulation propulsion mode of carangiform fish and jet propulsion mode of jellyfish together organically. The use of Computational Fluid Dynamics (CFD) and experimental method helps to reveal the effect of caudal fin stiffness and motion parameters on its hydrodynamic forces.

First, the prototype of BUR was given by mimicking the shape and propulsion mechanism of both carangiform fish and jellyfish. Besides, the kinematics models in both undulation and jet propulsion modes were established. Then, the effects of caudal fin stiffness on its hydrodynamic forces were investigated based on the CFD method. Finally, an experimental set-up was developed to test and verify the effects of the caudal fin stiffness on its hydrodynamic forces under different caudal fin actuation frequency and amplitude.

The results of this paper demonstrate that BUR with multi-flexible caudal fins combines the hydrodynamic characteristics of undulation and jet propulsion modes. In addition, the caudal fin with medium stiffness can generate larger thrust force and reduce the reactive power.

This paper implies that robotic fish can be equipped with both undulation and jet propulsion modes to optimize the swimming performance in the future.

This paper provides a BUR with multi-propulsion modes, which has the merits of high propulsion efficiency, high acceleration performance and overcome the head shaken problem effectively.

China and the USA are among the countries where depression is most prevalent. However, the treatment rate of depression is relatively low in these two countries. Negative attitudes toward depression is one of the major contributor to the low-treatment rate. The purpose of this paper is to examine the use of narratives to promote positive attitudes toward depression in China and the USA. In addition, it examines that the psychological mechanisms underlying narrative persuasion in these two different cultural contexts.

An online survey was conducted in both China (n=84) and the USA (n=174). Participants were first asked to complete a short questionnaire about their demographic information and depressive symptoms. They were then asked to read a story featuring a college student with depression. After reading the message, participants completed another questionnaire measuring their attitudes toward depression, transportation (i.e. readers’ involvement with the story), and counterarguing (i.e. the generation of thoughts that dispute the persuasive argument).

Results from a multi-group analysis suggested that although narrative messages had similar persuasive effects for readers from different cultures, the relation between narrative transportation and counterarguing was different. For the US participants, the more they were transported to the story world, the less counter arguments they generated. However, transportation was not negatively associated with counterarguing for Chinese readers.

Findings provide implications for strategically using narrative persuasion to promote positive attitudes toward depression in different cultural contexts.

This study is the first to test the use of narratives to promote positive attitudes toward depression in different cultural contexts.

Geographical conditions monitoring (GCM) has elicited significant concerns from the Chinese Government and is closely related to the “Digital China” program. This research aims to focus on object-based change detection (OBCD) methods integrating very-high-resolution (VHR) imagery and vector data for GCM.

The main content of this paper is as follows: a multi-resolution segmentation (MRS) algorithm is proposed for obtaining homogeneous and contiguous image objects in two phases; a post-classification comparison (PCC) method based on the nearest neighbor algorithm and an image-object analysis (IOA) technique based on a differential entropy algorithm are used to improve the accuracy of the change detection; and a vector object-based accuracy assessment method is proposed.

Results show that image objects obtained using the MRS algorithm attain the objectives of the “same spectrum within classes” and “different spectrum among classes”. Moreover, the two OBCD methods can detect over 85 per cent of the changed regions. The PCC strategy can obtain the categories of image objects with a high degree of precision. The IOA technique is easy to use and largely automated.

On the basis of the VHR satellite imagery and vector data, the above methods can effectively and accurately provide technical support for GCM implementation.

This paper aims to address the safety concerns of path-planning algorithms in dynamic obstacle warehouse environments. It proposes a method that uses improved artificial potential fields (IAPF) as expert knowledge for an improved deep deterministic policy gradient (IDDPG) and designs a hierarchical strategy for robots through obstacle detection methods.

The IAPF algorithm is used as the expert experience of reinforcement learning (RL) to reduce the useless exploration in the early stage of RL training. A strategy-switching mechanism is introduced during training to adapt to various scenarios and overcome challenges related to sparse rewards. Sensor inputs, including light detection and ranging data, are integrated to detect obstacles around waypoints, guiding the robot toward the target point.

Simulation experiments demonstrate that the integrated use of IDDPG and the IAPF method significantly enhances the safety and training efficiency of path planning for mobile robots.

This method enhances safety by applying safety domain judgment rules to improve APF’s security and designing an obstacle detection method for better danger anticipation. It also boosts training efficiency through using IAPF as expert experience for DDPG and the classification storage and sampling design for the RL experience pool. Additionally, adjustments to the actor network’s update frequency expedite convergence.

The purpose of this paper is to facilitate understanding of how to convert free players to paid consumers in free-to-play games.

Drawing on the consumption value framework and affordance theory, the present study argues that in-game purchase behaviors are determined by multiple consumption values of in-game items. The perceptions of consumption values were influenced by game affordances. The model was tested, using data from an empirical survey with 2,006 free-to-play game players.

Monetary, enjoyment and social values of in-game items positively predict purchase behaviors in free-to-play games. Game fairness and balance of challenges and skills significantly influence perceived enjoyment value.

The findings of this study provide operable implications to facilitate in-game consumption. The model was tested within the context of free-to-play multiplayer online battle arena (MOBA) games; however, caution is advisable when generalizing the findings to other subgenre of games.

This study extended and thus validated the consumption value framework in the context of free-to-play MOBA games. This study explored the antecedents of consumption values from the perspective of game affordance.

Previous studies have rarely integrated the financing modes of a capital-constrained manufacturer with the choices of online sales strategies. To address this gap, the authors study how a manufacturer selects optimal financing modes under different sales strategies in three dual-channel supply chains.

This paper considers three sales strategies, namely, combining a traditional retailer channel with one of the direct selling, reselling and agency selling channels, and two common financing modes, namely, bank financing and retailer financing. The authors obtain equilibrium outcomes of the manufacturer and traditional retailer and then provide the conditions for them to select optimal financing modes under three sales strategies.

The results indicate that the manufacturer’s financing decisions rely on the initial capital and interest rates, and the manufacturer selects retailer financing only if the initial capital is relatively larger. In terms of financing mode options, the retailer financing mode is more beneficial for the manufacturer under the three sales strategies. From the perspective of sales strategies, the direct selling model is more beneficial. In addition, the higher the consumer acceptance of the online channel, the more profits the manufacturer obtains.

This paper provides suggestions on how the capital-constrained manufacturer chooses financing modes and sales strategies.

This paper integrates the financing mode and different sales strategies to investigate the manufacturer’s optimal operational decisions. These sales strategies allow us to investigate the manufacturer’s optimal financing modes in the presence of both different financing modes and sales strategies.

The purpose of this paper is to examine the prevalence and psychosocial correlates of fear of crime in older Chinese. Attempt was made to test a theoretical model which integrated the vulnerability model, “broken windows” theory, victimization theory and risk interpretation model.

A cross-sectional survey was conducted with 453 older adults from a representative sample recruited from Kunming using stratified sampling methods.

More than half of the participants (n=258, 57.0 percent) reported fear of one or more types of depicted common crime. By comparison, a smaller percentage (n=57, 12.6 percent) reported fear of domestic violence (FDV). Correlational analysis indicated different correlates for fear of common crime (FCC) and FDV. Female gender, a younger age, poor financial and health statuses, perception of greater social instability and neighborhood disorder, direct and/or indirect victimization and perception of a higher risk of victimization were significantly associated with higher levels of FCC. Limited social networks, perception of greater neighborhood disorder, direct and/or indirect victimization and perception of a higher risk of victimization were salient correlates of FDV. The results of hierarchical regression analyses showed that the integrated model explained 37 and 43 percent of the variance in FCC and FDV, respectively.

This study found diverse patterns in terms of the prevalence and risk factors for FCC and FDV. The findings have important implications for policy, practice and research.