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A risk-based method is proposed to identify the dominant influencing factors of secondary lining cracking in an operating mountain tunnel with weak surrounding rock.

Based on the inspection data from a mountain tunnel in Southwest China, a lognormal proportional hazard model is established to describe the statistical distribution of secondary lining cracks. Then, the model parameters are obtained by using the Bayesian regression method, and the importance of influencing factors can be sorted based on the absolute values of the parameters.

The results show that the order of importance of the influencing factors of secondary lining cracks is as follows: location of the crack on the tunnel profile, rock mass grade of the surrounding rock, time to completion of the secondary lining, and void behind the secondary lining. Accordingly, the location of the crack on the tunnel profile and rock mass grade of the surrounding rock are the two most important influencing factors of secondary lining cracks in the investigated mountain tunnel, and appropriate maintenance measures should be focused on these two aspects.

This study provides a general and effective reference for identifying the dominant influencing factors of secondary lining cracks to guide the targeted maintenance in mountain tunnels.

This paper aims at examining the emergence of the current structure of the real estate agency businesses in Beijing in the age of information technology.

The study utilises the analytical framework developed under the Grounded Theory model by coding the interview results with six major real estate agencies in Beijing.

The model explains the metamorphosis development of a new sector of service agents in the society which itself is undergoing colossal changes in the socio‐economic system. The analysis shows that the impact of information technology does not pose a threat to these agents in Beijing in various circles, but works to increase the competitive advantages inducing more collaboration and market innovations.

The research is limited to the city of Beijing only and generalisation of the conclusion from the analysis needs to be qualified carefully for other cities in China, or even other countries.

The advent of information technology, especially in the last decade has set the momentum for changes in various sectors of our society. However, the impact is not felt evenly on each of these sectors in the society. The service industry is a typical example where a wide spectrum of sub‐sectors exists, ranging from close personal services such as hairdressing to information selling. The degree of impact from the new era of information revolution varies with the nature of each sub‐sector.

The purpose of this paper is to examine how limited care patients and comprehensive care patients differ in terms of consumers' behavior in the dentist selection process, in order to help healthcare providers and marketers better promote their practice depending on their patient type.

A survey of 1,150 dental school faculty private practice patients who recently chose their dentist was conducted and 221 responded. The respondents were divided to comprehensive care patients (n=120) and limited care patients (n=90) by self‐perceived need.

The comprehensive care patients were younger and more likely to be highly educated, have a healthcare related profession, and have private dental insurance (p<0.001). The comprehensive care patients were more likely to use information sources such as clinic website, the internet, and the insurance directory (p<0.05), while the limited care patients were more likely to use other dentists. Comprehensive care patients put more value on attributes such as, the dentist is in my insurance network and convenient physical location (p<0.05). In conclusion, comprehensive care patients and limited care patients differed significantly in characteristics and how and why they chose their dentist.

Healthcare marketers can use this study's findings to better promote their practice by selecting appropriate communication channels and focus on attributes that consumers value the most. It is important to apply different strategies to different consumer groups.

This paper aims to study the effect of the establishment of bankruptcy courts on bond issuance market. This paper helps to predict that the introduction of bankruptcy courts in China can mitigate price distortions caused by the implicit government guarantees and promote the development of the high-risk bond market.

This paper exploits the staggered introduction of bankruptcy courts across cities to implement a differences-in-differences strategy on bond issuance data. Using bonds issued in China between 2018 and 2020, the impact of bankruptcy courts on the bond issuance market can be analyzed.

This paper reveals that bond issuance credit spreads increase and is more sensitive to firm size, profitability and downside risk of issuance entity after the introduction of bankruptcy courts. It also reveals a substantive increase in bond issuance quantity and a decrease in issuer credit ratings following the establishment of bankruptcy courts. In addition, the increase of credit spreads is more prominent for publicly traded bonds, those whose issuers located in provinces with lower judicial confidence, bonds issued by SOEs and bonds with stronger government guarantees. Finally, the role of bankruptcy courts is more pronounced in regions with higher marketization.

This paper relates to previous studies that investigate the impact of laws and institutions on external financing. It helps provide new evidence to this literature on how improvements of efficiency and quality in bankruptcy enforcements relate to the marketization of bond issuance. The results provide further evidence on legal institutions and bond financing.

From practical perspectives and to improve the working efficiency, trolley transportation and payload hoisting/lowering should be simultaneously controlled. Moreover, in practical crane applications, the transportation time is an important criterion for improving transportation efficiency. Based on these requirements, this paper aims to solve positioning and antiswing control problems and shorten the transportation time for underactuated varying-rope-length overhead cranes.

By choosing trolley acceleration and varying-rope-length acceleration as system inputs, the crane system dynamic model is converted into an equivalent model without linearizing/approximating. Then, based on the converted model and system state constraints, a time-optimal problem is formulated. Further, the original problem is converted into an optimization problem with algebraic constraints which can be conveniently solved. Finally, by solving the optimization problem, the optimal trajectories of system states, including displacements, velocities and accelerations, are obtained.

This paper first provides a nonlinear time-optimal trajectory planner for varying-rope-length overhead cranes, which achieves accurate and fast trolley positioning and eliminates payload residual swings. Meanwhile, all system states satisfy the given constraints during the entire process. Hardware experimental results show that the proposed time-optimal planner is effective and has better performance compared with existing methods.

This paper proposes a time-optimal trajectory planner for overhead crane systems with hoisting/lowering motion. The proposed planner achieves fast trolley positioning and eliminates payload residual swing with all the system states being constrained within given scopes. The planner is presented based on the original nonlinear system dynamics without linearization/approximation.

The purpose of this paper is to propose a new algorithm for independent navigation of unmanned aerial vehicle path planning with fast and stable performance, which is based on pigeon-inspired optimization (PIO) and quantum entanglement (QE) theory.

A biomimetic swarm intelligent optimization of PIO is inspired by the natural behavior of homing pigeons. In this paper, the model of QEPIO is devised according to the merging optimization of basic PIO algorithm and dynamics of QE in a two-qubit XXZ Heisenberg System.

Comparative experimental results with genetic algorithm, particle swarm optimization and traditional PIO algorithm are given to show the convergence velocity and robustness of our proposed QEPIO algorithm.

The QEPIO algorithm hold broad adoption prospects because of no reliance on INS, both on military affairs and market place.

This research is adopted to solve path planning problems with a new aspect of quantum effect applied in parameters designing for the model with the respective of unmanned aerial vehicle path planning.

This study aims to examine the effects of natural, cultural and urban resources on the city's tourism competitiveness from the residents' perspective and identifies the factors that city managers should prioritize.

The authors used multiple methods. The partial least squares structural equation modeling tested our theoretical assumption and the importance–performance map analysis provided an extra interpretation of the results to make them tangible to city managers. Data collection was done with residents of Viseu, Portugal.

The findings indicated that tourism competitiveness from the residents' perspective depends on the leisure activities they can enjoy as much as tourists, as the limits between tourism activities and everyday life are tenuous. The quality of leisure is part of residents' well-being; however, the results suggested that tourism development fails to engage residents in the destination's leisure offer. The cultural heritage is not attractive to them because it is part of their day-by-day living area or they need to enjoy the cultural offer. To accommodate residents' demands, destination managers need to improve the offer of outdoor activities and urban leisure opportunities.

The main limitations were the sample size and the data collection after a pandemic context, that is, in a period of economic crisis that reduced leisure consumption. The implications point out variables to managers prioritize to improve place management and rethink tourism competitiveness based on a citizen-centered view. It is also a way to understand residents as staycationers.

Our research contributed to urban and city research literature with meaningful findings that can help city managers improve the positive impacts of tourism on residents and enhance the integration of tourism and urban daily life.

The authors suggested strategies for integrating residents into cultural activities.

Theoretically, this study is set up in the frontier of rethinking and promoting society-centric tourism development. The research contributed to urban and city research literature with meaningful findings that can help city managers improve the positive impacts of tourism on residents and enhance the integration of tourism and urban daily life. In this direction, the authors suggest strategies for integrating residents into cultural activities.

The purpose of the study is to observe the feasibility of missing middle housing’s (MMH) realization under density-based zoning, form-based zoning and a combination of both while simultaneously providing affordable housing, improving quality of life and making efficient use of land.

This study takes a theorist approach and designs three hypothetical cottage court projects that comply with all relevant official local zoning ordinances to showcase design feasibility, followed by an analytical component in the form of a financial model constructed using official local economic and demographic conditions.

MMH, and in particular cottage clusters, can be implemented under rigorous density-based, form-based and hybrid (density-based + form-based) zoning ordinances and provide affordable housing (Atlanta, GA), improve quality of life (Blackpool, UK) and make efficient use of land (Jinan, China). All hypothetical projects are financially feasible under reasonable conditions.

To the best of the author’s knowledge, this paper is the first in the body of knowledge to discuss how the MMH can be integrated into urban density-based zoning rather than converting density-based zoning into form-based so that the MMH can fit. The paper also takes a cross-national perspective and discusses the feasibility of MMH in the resolution of housing issues in the USA, China and the UK. The study also concludes that the issue of housing unaffordability in the UK was caused by high construction cost relative to median income.

This paper aims to give an overview about the state of wireless passive surface acoustic wave (SAW) gas sensor used in the detection of chemical vapor. It also discusses a variety of different architectures including delay line and array sensor for gas detection, and it is considered that this technology has a good application prospect.

The authors state the most of the wireless passive SAW methods used in gas sensing, such as CO2, CO, CH4, C2H4, NH3, NO2, et al., the sensor principles, design procedures and technological issues are discussed in detail; their advantages and disadvantages are also summarized. In conclusion, it gives a prospect of wireless passive SAW sensor applications and proposes the future research field might lie in the studying of many kinds of harmful gases.

In this paper, the authors will try to cover most of the important methods used in gas sensing and their recent developments. Although wireless passive SAW sensors have been used successfully in harsh environments for the monitoring of temperature or pressure, the using in chemical gases are seldom reported. This review paper gives a survey of the present state of wireless passive SAW sensor in gas detection and suggests new and exciting perspectives of wireless passive SAW gas sensor technology.

The authors will review most of the methods used in wireless passive SAW sensor and discuss the current research status and development trend; the potential application in future is also forecasted.

The authors will review most of the methods used in wireless passive SAW sensor and discuss the current research status and development trend; the potential application in future is also forecasted.