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Although extensive research has been conducted on precast production, irregular component loading constraints have received little attention, resulting in limitations for transportation cost optimization. Traditional irregular component loading methods are based on past performance, which frequently wastes vehicle space. Additionally, real-time road conditions, precast component assembly times, and delivery vehicle waiting times due to equipment constraints at the construction site affect transportation time and overall transportation costs. Therefore, this paper aims to provide an optimization model for Just-In-Time (JIT) delivery of precast components considering 3D loading constraints, real-time road conditions and assembly time.

In order to propose a JIT (just-in-time) delivery optimization model, the effects of the sizes of irregular precast components, the assembly time, and the loading methods are considered in the 3D loading constraint model. In addition, for JIT delivery, incorporating real-time road conditions in the transportation process is essential to mitigate delays in the delivery of precast components. The 3D precast component loading problem is solved by using a hybrid genetic algorithm which mixes the genetic algorithm and the simulated annealing algorithm.

A real case study was used to validate the JIT delivery optimization model. The results indicated this study contributes to the optimization of strategies for loading irregular precast components and the reduction of transportation costs by 5.38%.

This study establishes a JIT delivery optimization model with the aim of reducing transportation costs by considering 3D loading constraints, real-time road conditions and assembly time. The irregular precast component is simplified into 3D bounding box and loaded with three-space division heuristic packing algorithm. In addition, the hybrid algorithm mixing the genetic algorithm and the simulated annealing algorithm is to solve the 3D container loading problem, which provides both global search capability and the ability to perform local searching. The JIT delivery optimization model can provide decision-makers with a more comprehensive and economical strategy for loading and transporting irregular precast components.

The paper aims to investigate effectiveness of the strengthening method, the construction process monitoring, fielding-load tests before and after strengthening, and health monitoring after reinforcement were carried out. The results of concrete strain and deflection show that the flexural strength and stiffness of the strengthened beam are improved.

This paper describes prestressed steel strand as a way to strengthen a 25-year-old continuous rigid frame bridge. High strength, low relaxation steel strand with high tensile strain and good corrosion resistance were used in this reinforcement. The construction process for strengthening with prestressed steel strand and steel plate was described. Ultimate bearing capacity of the bridge after strengthening was discussed based on finite element model.

The cumulative upward deflection of the second span the third span was 39.7 mm, which is basically consistent with the theoretical value, and the measured value is smaller than the theoretical value. The deflection value of the second span during data acquisition was −20 mm–10 mm, which does not exceed the maximum deflection value of live load, and the deflection of the bridge is in a safe state during normal use. Thus, this strengthened way with prestressed steel wire rope is feasible and effective.

This paper describes prestressed steel strand as a way to strengthen a 25-year-old continuous rigid frame bridge. To investigate effectiveness of the strengthening method, the construction process monitoring, fielding-load tests before and after strengthening and health monitoring after reinforcement were carried out.

In this paper, taking a p-section girder cable-stayed bridge as an example, the construction monitoring and load test of the bridge are implemented.

In order to ensure the safety of cable-stayed bridge structure in construction and achieve the internal force state of the completed bridge, the construction process is monitored for liner and stress of the p-section girder, construction error and safety state during construction. At the same time, to verify whether the bridge can meet the design requirements, the static and dynamic load tests are done.

The results of construction monitoring show that the stress state of the structure during construction is basically consistent with the theoretical calculation and design requirements. The final measured stress state of the structure is within the allowable range of the cable-stayed bridge, and the structural stress state is normal and meets the specification requirements. The load tests results show that the measured deflection of the midspan section of the main girder is less than the theoretical calculation value. The maximum deflection of the main girder is 48.03 mm, which is less than 54.25 mm of the theoretical value, indicating that the main girder has sufficient structural stiffness. Under the dynamic load test, the natural frequency of the three spans of the bridge is less than the theoretical frequency.

This study can provide important reference value for the construction and maintenance of similar p-section girder cable-stayed bridges.

The purpose of this study is to demonstrate the nonlinear relationship between inventory stickiness and productivity, with investment efficiency being a mediator and environmental dynamism being a moderator.

Using a large panel data collected from 1,479 Chinese listed manufacturing enterprises over the period from 2010 to 2020, this research employs the instrumental variable method combined with two-stage least squares estimators to explore the inverted-U-shaped relationship between inventory stickiness and productivity. Furthermore, the mediating role of investment efficiency and the moderating role of environmental dynamism are demonstrated via two three-model systems.

As its core, productivity initially increases with inventory stickiness until a turning point at the end of the sample, beyond which the incremental effect of inventory stickiness on productivity become negative. That is, an inverted U-shaped relationship between inventory stickiness and productivity is found to exist. Moreover, further mediated moderation analysis highlights that investment efficiency is a key mediator of this relationship, whereas environmental dynamism is a key moderator.

Managers ought to gauge carefully against the tradeoffs between inventory stickiness and productivity. In general, over 90% of manufacturing enterprises have great potential to increase productivity by implementing sticky inventory management. In addition, managers are suggested to place emphasis on investment management and environmental strategy.

This paper contributes to the current understanding about productivity by illustrating and verifying the nonlinear effect of sticky inventory management. It may be the first study to empirically demonstrate the mediating effect of investment efficiency and the moderating effect of environmental dynamism on the relationship between inventory stickiness and productivity.

This paper aims to examine and compare the associations between financial capability and financial anxiety (FA) before and during the coronavirus disease 2019 (COVID-19) pandemic. Specifically, financial capability is measured by three indicators: financial knowledge, financial behavior and financial confidence. This study also examines and compares the association among different income groups before and during the pandemic.

Data are from 2018 to 2021 National Financial Capability Study (NFCS). Structural equation modeling (SEM) is employed to examine the direct and indirect associations between financial capability factors and FA. Furthermore, this paper also conducts multi-group SEM for three income groups to examine the heterogeneous effects of household income.

Both before and during the pandemic, financial knowledge is directly positively and financial behavior is directly negatively associated with FA. In addition, both financial knowledge and financial behavior are positively associated with financial confidence, which in turn is negatively associated with FA. However, when taking the indirect effects into consideration, the total effects of financial capability factors on FA are all negative. Furthermore, the pandemic has intensified the negative association between financial behavior and FA rather than financial knowledge or financial confidence. Multi-group SEM shows that the positive direct effects of financial knowledge are only significant in the low-income group, while the negative direct effects of financial behavior are only significant in the low- and middle-income groups before the pandemic. However, direct effects of financial knowledge and financial behavior are significant in all income groups during the pandemic.

First, this study specifies a construct, financial confidence, to proxy perceived financial capability. Second, it examines the mediating role of financial confidence in the association between the other two financial capability factors (financial knowledge and financial behaviors) and FA. Third, it also compares the associations between financial capability factors and FA before and during the COVID-19 pandemic.

Sustainability is of growing significance in the contemporary business landscape as organizations strive to minimize their environmental impact and optimize supply chain (SC) operations. Gaining insights into the influence of Triple A SC practices on sustainable performance can offer valuable perspectives for practitioners and policymakers. This study aims to comprehensively review existing academic literature on Triple A supply chain management (SCM) and sustainability, examining its impact on sustainable performance while identifying key influencing factors.

This review follows the six steps and 14 decisions of conducting a systematic literature review to comprehensively review 57 papers published between 2004 and 2023.

Based on the content analysis of the selected papers, this study summarizes the antecedents, practices and outcomes of Triple A SCM, with a particular focus on its implications for sustainability. This paper builds a conceptual framework from the descriptive and thematic findings to enrich the relevant aspects of Triple A SCM.

This study establishes a connection between Triple A SCM and sustainable performance by examining its impact on economic, social and environmental aspects. This review identifies research gaps and acknowledges the lack of specificity in implementing Triple A SCM across diverse industries, regions and competitive markets with varying external environments. It emphasizes the necessity to customize approaches based on contextual factors and provides valuable recommendations for future research to advance the concept of Triple A SCM.

To remedy the inherent defect in current research that focuses only on a single type of participants, this paper endeavors to look into the situation as an evolutionary game between a representative Logistics Service Integrator (LSI) and a representative Functional Logistics Service Provider (FLSP) in an environment with sudden crisis and tries to analyze how LSI supervises FLSP's operations and how FLSP responds in a recurrent pattern with different interruption probabilities.

Regarding the risks of supply chain interruption in emergencies, this paper develops a two-level model of single LSI and single FLSP, using Evolutionary Game theory to analyze their optimal decision-making, as well as their strategic behaviors on different risk levels regarding the interruption probability to achieve the optimal return with bounded rationality.

The results show that on a low-risk level, if LSI increases the degree of punishment, it will fail to enhance FLSP's operational activeness in the long term; when the risk rises to an intermediate level, a circular game occurs between LSI and FLSP; and on a high level of risk, FLSP will actively take actions, and its functional probability further impacts LSI's strategic choices. Finally, this paper analyzes the moderating impact of punishment intensity and social reputation loss on the evolutionary model in emergencies and provides relevant managerial implications.

First, by taking both interruption probability and emergencies into consideration, this paper explores the interactions among the factors relevant to LSI's and FLSP's optimal decision-making. Second, this paper analyzes the optimal evolutionary game strategies of LSI and FLSP with different interruption probability and the range of their optimal strategies. Third, the findings of this paper provide valuable implications for relevant practices, such that the punishment intensity and social reputation loss determine the optimal strategies of LSI and FLSP, and thus it is an effective vehicle for LSSC system administrator to achieve the maximum efficiency of the system.

The aim of this study is to analyze the influence mechanism of real estate enterprises' status on debt default risk and explore the heterogeneity effect of the characteristics of enterprises.

Against the background of the “three red lines” regulation of the financing of real estate enterprises and the COVID-19 pandemic, the authors select 123 real estate enterprises listed on China's Shanghai and Shenzhen A-shares markets from the first quarter of 2021 to the second quarter of 2022 as a research sample. The social network analysis method and Z-score financial risk early warning model are used to measure real estate enterprises' status and debt default risk. The authors construct a panel regression model to analyze how the status of real estate enterprises influences their debt default risk.

The results show that the status of real estate enterprises negatively and significantly affects their debt default risk. Economic policy uncertainty and financing constraints play negative moderating and mediating roles, respectively. Further research has found that the effect of real estate enterprises' status on debt default risk is characterized by heterogeneity in equity characteristics, i.e. it is significant in the sample of nonstate-owned enterprises but not in the sample of state-owned enterprises.

It is helpful for real estate enterprises to attach importance to the value of social networks, and the authors provide policy suggestions for real estate enterprises to constantly improve their risk management systems.

Using economic policy uncertainty as the moderating variable and financing constraints as the mediating variable, the authors analyze how the status of real estate enterprises influences debt default risk, which contributes to a better understanding of the formation of the debt default risk of real estate enterprises.

The purpose of this paper is to develop a novel wearable rehabilitation robotic hand driven by Pneumatic Muscle‐Torsion Spring (PM‐TS) for finger therapy. PM has complex nonlinear dynamics, which makes PM modelling difficult. To realize high‐accurate tracking for the robotic hand, an Echo State Network (ESN)‐based PID adaptive controller is proposed, even though the plant model is unknown.

To drive a single joint of rehabilitation robotic hand, the paper proposes a new PM‐TS actuator comprising a Pneumatic Muscle (PM) and a Torsion Spring (TS). Based on the novel actuator, a wearable robotic hand is designed. By employing the model‐free approximation capability of ESN, the RLSESN based PID adaptive controller is presented for improving the trajectory tracking performance of the rehabilitation robotic hand. An ESN together with Recursive Least Square (RLS) is called a RLSESN, where the ESN output weight matrix is updated by the online RLS learning algorithm.

Practical experiments demonstrate the validity of the PM‐TS actuator and indicate that the performance of the RLSESN based PID adaptive controller is better than that of the conventional PID controller. In addition, they also verify the effectiveness of the proposed rehabilitation robotic hand.

A new PM‐TS actuator configuration that uses a PM and a torsion spring for bi‐directional movement of joint is presented. By utilizing the new PM‐TS actuator, a novel wearable rehabilitation robotic hand for finger therapy is designed. Based on the unknown plant model, the RLSESN_PID controller is proposed to attain satisfactory performance.

This study aims to find the characteristics of supercritical airfoil in helicopter rotor blades for hovering phase using numerical analysis and the validation using experimental results.

Using numerical analysis in the forward phase of the helicopter, supercritical airfoil is compared with the conventional airfoil for the aerodynamic performance. The multiple reference frame method is used to produce the results for rotational analysis. A grid independence test was carried out, and validation was obtained using benchmark values from NASA data.

From the analysis results, a supercritical airfoil in hovering flight analysis proved that the NASA SC rotor produces 25% at 5°, 26% at 12° and 32% better thrust at 8° of collective pitch than the HH02 rotor. Helicopter performance parameters are also calculated based on momentum theory. Theoretical calculations prove that the NASA SC rotor is better than the HH02 rotor. The results of helicopter performance prove that the NASA SC rotor provides better aerodynamic efficiency than the HH02 rotor.

The novelty of the paper is it proved the aerodynamic performance of supercritical airfoil is performing better than the HH02 airfoil. The results are validated with the experimental values and theoretical calculations from the momentum theory.