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The purpose of this paper is twofold: first, to develop a performance evaluation framework for construction and demolition waste management (CDWM); second, to investigate feasible and effective strategies to improve the CDWM performance.

A review of the literature highlighted a lack of comprehensive research to evaluate CDWM performance of key project stakeholders, like owners, contractors and consultants. After the identification of 22 performance variables through a pilot study, a first questionnaire survey was conducted to investigate the views of respondents toward CDWM performance. The 132 responses were analyzed using factor analysis to determine specific CDWM performance factors, which formed a conceptual performance evaluation framework of CDWM. Furthermore, a practical index (PI) was proposed to integrate the feasibility and effectiveness of CDWM strategies. The values of PI were employed to prioritize CDWM strategies from data collected in a second questionnaire survey.

The validated results from factor analysis revealed that the conceptual performance evaluation framework of CDWM consists of six factors; and the attitude toward CDWM emerged as the foremost critical factor. The prioritization of PI values indicated that raising CDWM awareness among construction stakeholders was the most feasible and effective strategy for CDWM.

This CDWM performance evaluation framework is one of the first to holistically evaluate CDWM from key stakeholder perspectives. In addition, the PI firstly enables quantitative integration of the feasibility and effectiveness of CDWM strategies.

This paper aims to propose a comprehensive framework for prioritizing complexity criteria. The framework was validated by applying in infrastructure international development (ID) project as a case study.

A literature review highlighted the limitations of existing complexity prioritization methods. Then, a combination of the fuzzy decision-making trial and evaluation laboratory (DEMATEL) and fuzzy analytic network process (ANP) was employed as a foundation to develop a three-stage complexity prioritization framework. Focus group discussion and questionnaire surveys were used to practically test the framework in the infrastructure ID projects.

The three-stage complexity prioritization framework was validated to be reliable and feasible. The findings showed ability of consultants, scope uncertainties, site compensation and clearance, communication between stakeholders, administrative procedure and project duration were the most significant complexity criteria of ID projects in the Vietnamese context.

The framework is a robust tool that enables the researchers to grasp the interaction of complexity criteria for complexity prioritization. Later studies can apply the proposed framework, with some minor revisions, to assess the interaction of criteria in other research topics in, and beyond, project complexity. Results of the case study suggest project stakeholders focusing on complex interactions among criteria to reduce project complexity.

This study contributes to the body of knowledge by providing a comprehensive complexity prioritization framework that grasps the interrelationship of complexity criteria. For stakeholders of ID projects, the findings provide insightful perspectives to understand complexity, which can help to enhance project performance.

The purpose of this study is to identify driving factors and a quantitative model for implementing public-private partnership (PPP) projects in Ethiopia as a case study in emerging economies.

A review of the literature and semi-structured interviews were carried out to identify driving factors affecting the implementation of PPP projects in the Ethiopian context. Data were collected through a questionnaire survey within three months, with 59 validated responses; mean score technique and factor analysis were conducted. The fuzzy synthetic evaluation (FSE) method was applied to develop a driving index (DI) for implementing infrastructure PPP projects. Finally, a comparative analysis of top-five drivers was conducted between four emerging economies.

Mean values show that all driving variables are important. Through factor analysis, 22 identified driving variables were grouped into six factors, namely, benefit for public and private sectors, attention of private sector, social development, cost reduction, management ability of public sector and ability of private sector. The FSE method constructs a DI and shows that benefit for public and private sectors is the most crucial factor for PPP implementation in the context of Ethiopia. Apart from this, most driving forces for adopting PPP projects in these countries related to financial problems.

This study is one of the first integrate driving factors for PPP implementation. The index provides the decision-makers with a comprehensive tool to assess the needs of PPP implementation.

Generally, humanoid robots usually suffer significant impact force when walking or running in a non-predefined environment that could easily damage the actuators due to high stiffness. In recent years, the utilization of passive compliant series elastic actuators (SEA) for driving humanoid's joints has proved the capability in many aspects so far. However, despite being widely applied in the biped robot research field, the stable control problem for a humanoid powered by the SEAs, especially in the walking process, is still a challenge. This paper proposes a model reference adaptive control (MRAC) combined with the back-stepping algorithm to deal with the parameter uncertainties in a humanoid's lower limb driven by the SEA system. This is an extension of our previous research (Lanh et al., 2021).

Firstly, a dynamic model of SEA is obtained. Secondly, since there are unknown and uncertain parameters in the SEA model, a Model Reference Adaptive Controller (MRAC) is employed to guarantee the robust performance of the humanoid's lower limb. Finally, an experiment is carried out to evaluate the effectiveness of the proposed controller and the SEA mechanism.

This paper proposes an effective control algorithm that can be widely applied for the humanoid-SEA system. Besides, the effect of the coefficients in the control law is analyzed to further improve the response's quality.

Even though the simulation shows good results with stable system response, the practical experiment has not been implemented to fully evaluate the quality of the controller.

The MRAC is applied to control the humanoid's lower limb and the back-stepping process is utilized to combine with an external SEA system but still maintain stabilization. The simplified model of the lower-limb system proposed in the paper is proven to be appropriate and can be taken for further research in the future.

This study examines employee emotional exhaustion and turnover intention as the consequences of problematic customer behaviors and tests the role of perceived organizational justice and job satisfaction in mitigating these consequences.

A four-hypothesis model was tested using partial least squares structural equation modeling (PLS-SEM) based on a two-phase survey of 369 frontline services employees in Vietnam with a three-month time lag.

The study shows that abusive and unreasonably demanding customer behaviors have positive effects on emotional exhaustion, which, in turn, reduces job satisfaction and, subsequently, turnover intention. It also reveals that organizational justice mechanisms attenuate the positive association between emotional exhaustion and turnover intention. Job satisfaction indirectly mitigated the turnover intention of emotionally exhausted employees who had to deal with problematic customer behaviors, especially in the service sector in Vietnam, an emerging market.

Building upon the social exchange theory (SET) and the conservation of resources theory (COR), this study extended the research on organizational justice with respect to emotional exhaustion in the customer service sector that received less attention previously. Rather than merely focusing on the interpersonal factors (e.g. respect and sensitivity) as organizational support does, organizational justice encompasses employees' perception of fairness of outcome and the whole process in an organization to reach decisions.

This study aims to investigate countries without national property insurance and see how experience affects behavior toward higher-risk flood prone property.

Using a unique data set that captures the flood experiences of homeowners that search for new housing, the authors examine the premiums or discounts of such experience on homes at risk. The authors use hedonic property modeling to estimate the effects of experience on values.

The authors find that such experiences play a strong role in convincing buyers of the real risks imposed by climate change and sea level rise and the authors expect these demand-side behavioral changes to persist. This finding is unlike more developed markets where insurance may be subsidized and negative effects on value dissipate within a few years.

The world is starting to pay more attention to climate risk and the results in developed countries have been biased by the extensive insurance provided by the government or emergency funding.

Providing market transparency on climate risks will result in permanent market effects, if not otherwise subsidized.

The governments should encourage market disclosure.

No one has ever had a data set like this before where the authors get to observe the behavior of those already experiencing property losses from flooding.

Humanoid robots have been utilized in many fields such as medical, construction, and disaster response. While humanoid robots nowadays can achieve great capabilities, the one-leg balancing task still poses a challenging problem. This paper aims to propose a novel approach to solve the problem.

To aid the balance of one leg in humanoid robot, an external balance mechanism is inserted to the back of the humanoid robot. First, a dynamic model of the humanoid robot with balance mechanism and its simplified model are introduced. Second, a backstepping-based control method is utilized to build the proposed controller for one-leg stance system through two steps. For the first step, a minimum observer-based controller with a virtual control input is used to control the first sub-system reaching the desired reference input. For the second step, a virtual control input is considered as a reference input of a second sub-system, then a model reference adaptive controller (MRAC) is employed to control the second sub-system reaching the virtual control input in presence of uncertainties. By using the external balance mechanism, the sideway balancing task is separated from normal walking function. Furthermore, the utilization of the balance mechanism ensures the humanoid robot's hip adduction does not exceed the threshold of a human when walking. Finally, a simulation study is carried out to evaluate the effectiveness of the proposed method.

This paper proposes a model reference adaptive control using state observer for balancing one leg of humanoid robot in stance phase that extends our previous research (Tran et al., 2021).

The main research contents have been introduced.

In the COVID-19 outbreak periods, people's life has been deranged, leading to disrupt the world. Firstly, the number of deaths is growing and has the potential to surpass the highest level at any time. Secondly, the pandemic broke many countries' fortified lines of epidemic prevention and gave people a more honest view of its seriousness. Finally, the pandemic has an impact on life, and the economy led to a shortage in medical, including a lack of clinicians, facilities and medical equipment. One of those, a simple ventilator is a necessary piece of medical equipment since it might be useful for a COVID-19 patient's treatment. In some cases, the COVID-19 patients require to be treated by modern ventilators to reduce lung damage. Therefore, the addition of simple ventilators is a necessity to relieve high work pressure on medical bureaucracies. Some low-income countries aim to build a simple ventilator for primary care and palliative care using locally accessible and low-cost components. One of the simple principles for producing airflow is to squeeze an artificial manual breathing unit (AMBU) iterative with grippers, which imitates the motion of human fingers. Unfortunately, the squeezing angle of grippers is not proportional to the exhaust air volume from the AMBU bag. This paper aims to model the AMBU bag by a mathematical equation that enables to implement on a simple controller to operate a bag-valve-mask (BVM) ventilator with high accuracy performance.

This paper provides a curvature function to estimate the air volume exhausting from the AMBU bag. Since the determination of the curvature function is sophisticated, the coefficients of the curvature function are approximated by a quadratic function through the experimental identification method. To obtain the high accuracy performance, a linear regression model and a least square method are employed to investigate the characteristic of the BVM ventilator's grippers angle with respect to the airflow volume produced by the AMBU bag.

This paper investigates the correlation between the exhausting airflow of the AMBU bag and the grippers angle of the BVM ventilator.

The experimental results validated that the regression model of the characteristic of the exhausting airflow of the AMBU bag with respect to the grippers' angle has been fitted with a coefficient over 98% within the range of 350–750 ml.

The paper aims to assess the impact of weather-induced shocks on household food consumption in the rural Vietnamese Mekong Delta (VMD) through the case of Long An province and evaluate the effectiveness of widely used coping strategies in mitigating weather-related shock impacts.

The system generalized method of moments (GMM) estimation method is applied to explore information on shock incidence, recovery, and time occurrences. The paper uses a sample of 272 repeated farming households from 5-wave survey data from 2008 to 2016, resulting in 1,360 observations.

The paper confirms the robust negative effect of a natural shock on food consumption. Additionally, using savings proves to be the most potent measure to smooth food consumption. Other favorable coping strategies are “getting assistance from relatives, friends” or “getting assistance from the Government, and non-government organizations (NGOs).” The mitigating effects are also traced in the current analysis.

Using caution when generalizing the results from Long An to the whole VMD is reasonable. The rather limited observations of coping strategies do not allow the authors to analyze any specific strategy.

The proposed approach employs the GMM technique and controls for endogenous coping strategies and thus provides accurate estimates of the effects of weather-related shocks and the mitigation effectiveness in the rural VMD.

This study aims to discover the impact of failure factors on stakeholder coordination performance (SCP) in the finishing phase of high-rise building projects.

Firstly, this study identifies potential failure factors affecting coordination performance as well as criteria for measuring SCP in the finishing phase of high-rise building projects. Afterwards, a survey questionnaire is designed to collect data from high-rise building projects in Vietnam. Using the factor analysis method, the study discovers the failure constructs. A structural equation model is then built to uncover the relationships between failure constructs and SCP.

The study identified four failure constructs which could significantly affect SCP, namely traditional adversarial relationship (TAR), incompetent parties (IP), poor project planning and organization (PPO) and delays of parties toward construction works (DP). The developed model indicated that TAR, PPO and IP significantly affected stakeholders' coordination performance in the finishing phase of high-rise building projects.

The results of the study fill the gap in knowledge by discovering the causal relationships between failure constructs and SCP in high-rise building projects. The results might provide an initial guideline for stakeholders during the finishing phase of high-rise building projects to enhance their coordination performance.