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The collocation-based stochastic response surface method (CSRSM) is widely used in geotechnical reliability analyses due to its efficiency and accuracy. Determining the optimal truncated order of the associated polynomial chaos expansion (PCE) is important, as it may strongly affect the practical applicability of CSRSM.

This study investigates the performance of different optimal order selection strategies used in the CSRSM and proposes a new cross-order validation method. First, several methods commonly used for optimal order selection are briefly reviewed, and their merits and limitations for reliability analyses are discussed. Then, an improved optimal order selection method that achieves a better trade-off between efficiency and accuracy is proposed.

In total, ten simple mathematical examples from the literature are employed to perform a preliminary test on the proposed method, and a comparative study is conducted to demonstrate its advantages with respect to some other existing methods.

A total of three typical geotechnical problems are employed to demonstrate the performance of the proposed method in geotechnical practice.

An improved optimal order selection method that achieves a better trade-off between efficiency and accuracy is proposed. The threshold value of the deterministic coefficient used for the proposed method is discussed.

To solve the problems of short battery life and low transportation safety of logistics drones, this paper aims to propose a design of logistics unmanned aerial vehicles (UAV) wing with a composite ducted rotor, which combines fixed wing and rotary-wing.

This UAV adopts tiltable ducted rotor combined with fixed wing, which has the characteristics of fast flight speed, large carrying capacity and long endurance. At the same time, it has the hovering and vertical take-off and landing capabilities of the rotary-wing UAV. In addition, aerodynamic simulation analysis of the composite model with a fixed wing and a ducted rotor was carried out, and the aerodynamic influence of the composite model on the UAV was analyzed under different speeds, fixed wing angles of attack and ducted rotor speeds.

The results were as follows: when the speed of the ducted rotor is 2,500 rpm, CL and K both reach maximum values. But when the speed exceeds 3,000 rpm, the lift will decrease; when the angle of attack of the fixed wing is 10° and the rotational speed of the ducted rotor is about 3,000 rpm, the aerodynamic characteristics of the wing are better.

The novelty of this work comes from a composite wing design of a fixed wing combined with a tiltable ducted rotor applied to the logistics UAVs, and the aerodynamic characteristics of the design wing are analyzed.

The purpose of this study is to propose a new coordinated dynamic demand lot-size and delivery planning problem (CDLSDP), in which the delivery policy is integrated into the coordinated dynamic demand lot-size problem (CDLSP).

As a non-deterministic polynomial complete (NP-complete) problem, this CDLSDP seems difficult to be solved by a polynomial-time method. To handle this problem effectively and efficiently, a four-phase heuristic that balances the setup and inventory costs in the coordinating and delivery stages is designed to find near-optimal solutions.

Numerous computational experiments show that the proposed four-phase heuristic is effective and efficient. For 1,800 experiments with different scales, and different joint setup costs, solutions by the proposed heuristic have an average gap no more than 1.34% from the optimal solution.

To decrease total system cost, the CDLSDP optimizes the time-phased replenishment and delivery schedule, which includes joint setup cost, item setup, delivery and inventory cost, for each period. An effective and efficient four-phase heuristic is designed to solve the CDLSDP.

Compared with the traditional CDLSP, the delivery policy is considered by the new CDLSDP. Moreover, the proposed four-phase heuristic is a good candidate for solving the CDLSDP.

A zero-day vulnerability is a complimentary ticket to the attackers for gaining entry into the network. Thus, there is necessity to device appropriate threat detection systems and establish an innovative and safe solution that prevents unauthorised intrusions for defending various components of cybersecurity. We present a survey of recent Intrusion Detection Systems (IDS) in detecting zero-day vulnerabilities based on the following dimensions: types of cyber-attacks, datasets used and kinds of network detection systems.

Purpose: The study focuses on presenting an exhaustive review on the effectiveness of the recent IDS with respect to zero-day vulnerabilities.

Methodology: Systematic exploration was done at the IEEE, Elsevier, Springer, RAID, ESCORICS, Google Scholar, and other relevant platforms of studies published in English between 2015 and 2021 using keywords and combinations of relevant terms.

Findings: It is possible to train IDS for zero-day attacks. The existing IDS have strengths that make them capable of effective detection against zero-day attacks. However, they display certain limitations that reduce their credibility. Novel strategies like deep learning, machine learning, fuzzing technique, runtime verification technique, and Hidden Markov Models can be used to design IDS to detect malicious traffic.

Implication: This paper explored and highlighted the advantages and limitations of existing IDS enabling the selection of best possible IDS to protect the system. Moreover, the comparison between signature-based and anomaly-based IDS exemplifies that one viable approach to accurately detect the zero-day vulnerabilities would be the integration of hybrid mechanism.

Based on the conservation of resources theory, the purpose of this paper is to develop and test the relationship between workplace ostracism and psychological distress of male employees. And depending on the leader member exchange (LMX) theory, it assumes that the relationship between workplace ostracism and psychological distress of male employees is moderated by the LMX.

For this, this study used a survey method and multiple regression analyses with multi-source data from 226 male Korean employees and their supervisors.

The results suggest the following. First, workplace ostracism was positively associated with job tension, emotional exhaustion and depressed moods at work for male employees. Second, there was a stronger positive relationship between workplace ostracism and job tension, or emotional exhaustion for male employees with low, as opposed to those with high, levels of LMX.

This study is the first one to examine the moderating effect of LMX on the relationship between workplace ostracism and psychological distress of male employees.

Contemporary stochastic optimal control by synergy of the probability density evolution method (PDEM) and conventional optimal controller exhibits less capability to guarantee economical energy consumption versus control efficacy when non-stationary stochastic excitations drive hysteretic structures. In this regard, a novel multiscale stochastic optimal controller is invented based on the wavelet transform and the PDEM.

For a representative point, a conventional control law is decomposed into sub-control laws by deploying the multiresolution analysis. Then, the sub-control laws are classified into two generic control laws using resonant and non-resonant bands. Both frequency bands are established by employing actual natural frequency(ies) of structure, making computed efforts depend on actual structural properties and time-frequency effect of non-stationary stochastic excitations. Gain matrices in both bands are then acquired by a probabilistic criterion pertaining to system second-order statistics assessment. A multi-degree-of-freedom hysteretic structure driven by non-stationary and non-Gaussian stochastic ground accelerations is numerically studied, in which three distortion scenarios describing uncertainties in structural properties are considered.

Time-frequency-dependent gain matrices sophisticatedly address non-stationary stochastic excitations, providing efficient ways to independently suppress vibrations between resonant and non-resonant bands. Wavelet level, natural frequency(ies), and ratio of control forces in both bands influence the scheme’s outcomes. Presented approach outperforms existing approach in ensuring trade-off under uncertainty and randomness in system and excitations.

Presented control law generates control efforts relying upon resonant and non-resonant bands, and deploys actual structural properties. Cost-function weights and probabilistic criterion are promisingly developed, achieving cost-effectiveness of energy demand versus controlled structural performance.

Based on the Sociometer Theory, this study aims to develop a comprehensive framework explaining how and when negative workplace gossip triggers distinct responses, including employee silence and compulsory citizenship behavior (CCB).

Two scenario-based experiments and a field survey were conducted to examine hypotheses. Study 1 (N = 149) manipulated workplace negative gossip and assessed the mediating effects of state self-esteem. Study 2 (N = 217) manipulated workplace negative gossip and consideration of future consequences (CFC) to verify the stability of the mediating mechanism and test the moderating effect of CFC. Study 3 (N = 321) tested the whole research model.

The findings indicate that negative workplace gossip decreases state self-esteem, resulting in silence among employees with low levels of CFC, while inducing CCB through state self-esteem among employees with high levels of CFC.

This study not only extends the research of negative workplace gossip by exploring its multifaceted impact on employee responses but also highlights the role of personality traits in shaping individuals’ response strategies.

The purpose of this paper is to make a comprehensive analysis of 354 publications about Pythagorean fuzzy sets (PFSs) from 2013 to 2020 in order to comprehensively understand their historical progress and current situation, as well as future development trend.

First, this paper describes the fundamental information of these publications on PFSs, including their data information, annual trend and prediction and basic features. Second, the most productive and influential authors, countries/regions, institutions and the most cited documents are presented in the form of evaluation indicators. Third, with the help of VOSviewer software, the visualization analysis is conducted to show the development status of PFSs publications at the level of authors, countries/regions, institutions and keywords. Finally, the burst detection of keywords, timezone review and timeline review are exported from CiteSpace software to analyze the hotspots and development trend on PFSs.

The annual PFSs publications present a quickly increasing trend. The most productive author is Wei Guiwu (China). Wei Guiwu and Wei Cun have the strongest cooperative relationship.

The implication of this study is to provide a comprehensive perspective for the scholars who take a fancy to PFSs, and it is valuable for scholars to grasp the hotspots in this field in time.

It is the first paper that uses the bibliometric analysis to comprehensively analyze the publications on PFSs. It can help the scholars in the field of PFSs to quickly understand the development status and trend of PFSs.

This study aims to determine the influences of explanatory factors on the efficacy of the implementation of corporate safety policy (CSP) in international projects from the perspective of international contractors.

Four explanatory factors were identified for the implementation of CSP in international projects based on literature review. A questionnaire survey was then conducted among Chinese organizations that have been involved in international projects. In total, 121 valid responses were received from the questionnaire survey and were modeled using logistic regression to examine the impact of each factor on the observed event of interest.

The factors related to the effectiveness of implementing CSP, including “attitudes toward safety management measures (ASMM),” “operational mechanism for safety regulations (OM),” “safety knowledge management system (SKMS)” and “systematic safety training scheme (STS),” were selected. The results revealed that OM and SKMS were significant predictors (p < 0.05) of the odds of implementation satisfaction of CSP, but ASMM and STS were not. The probability of satisfactory CSP implementation increased as the value of SKMS increased, whereas the probability of unsatisfactory implementation improved as the value of OM increased.

The questionnaire was distributed to respondents in international contractors headquartered in China. Other types of international organizations can be covered in future research. Furthermore, other factors, such as the local construction environment, should be considered in future studies.

The results provide new insights on CSP implementation overseas. Effective implementation of CSP contributes to the improvement of the safety performance of contractors. The practical significance of interpreting the influence factors is that the contractors can implement more efficient and targeted approaches and tools in the execution of their CSP. The impact of OM reminds safety managers of the synchronization of CSP as well as its implementation environment and characteristics. The effect of ASMM encourages contractors to adopt Web-based and digital knowledge management systems to improve the implementation efficiency of CSP.

The novelty of this study lies in the selection of factors and their impacts on CSP implementation in international projects. This study has also extended knowledge on normative safety in international projects based on quantitative modeling.

This study aims to explore whether and how workplace loneliness leads to cyberloafing and the role of leader problem-focused interpersonal emotion management in buffering this relationship.

Drawing on ego depletion theory, the authors propose that employees' workplace loneliness leads to cyberloafing via ego depletion, while leader interpersonal emotion management (i.e. leadership behavior targeted at managing employees' negative emotions) can help to alleviate the situation. To test this study’s predictions, the authors collected multisource data at three time points from a sample of 219 employee–colleague dyads.

The results show that workplace loneliness is positively related to cyberloafing and that ego depletion mediates this relationship. Leader problem-focused interpersonal emotion management weakens the relationship between workplace loneliness and ego depletion and the indirect relationship between workplace loneliness and cyberloafing via ego depletion such that the above relationships are weak (versus strong) when leader problem-focused interpersonal emotion management is high (versus low).

The study results suggest that workplace loneliness is an important hidden danger that leads to cyberloafing because lonely employees suffer more from ego depletion. Leaders' interpersonal emotion management strategy serves as a potential buffer for such a negative effect.