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Accurate prediction of the structural condition of urban critical infrastructure is crucial for predictive maintenance. However, the existing prediction methods lack precision due to limitations in utilizing heterogeneous sensing data and domain knowledge as well as insufficient generalizability resulting from limited data samples. This paper integrates implicit and qualitative expert knowledge into quantifiable values in tunnel condition assessment and proposes a tunnel structure prediction algorithm that augments a state-of-the-art attention-based long short-term memory (LSTM) model with expert rating knowledge to achieve robust prediction results to reasonably allocate maintenance resources.

Through formalizing domain experts' knowledge into quantitative tunnel condition index (TCI) with analytic hierarchy process (AHP), a fusion approach using sequence smoothing and sliding time window techniques is applied to the TCI and time-series sensing data. By incorporating both sensing data and expert ratings, an attention-based LSTM model is developed to improve prediction accuracy and reduce the uncertainty of structural influencing factors.

The empirical experiment in Dalian Road Tunnel in Shanghai, China showcases the effectiveness of the proposed method, which can comprehensively evaluate the tunnel structure condition and significantly improve prediction performance.

This study proposes a novel structure condition prediction algorithm that augments a state-of-the-art attention-based LSTM model with expert rating knowledge for robust prediction of structure condition of complex projects.

This study aims to examine the effects of dialect connectedness between the chairman and the chief executive officer (CEO) (DCCC) on the tunneling activities of controlling shareholders.

This study uses abnormal related-party transactions (ARPT) as a proxy for tunneling activities and traces dialects of chairmen and CEOs based on the respective birthplace information. Baseline results are examined using a fixed-effects model. The results remain robust when using the instrumental variable approach, propensity score matching (PSM) technique, changing the measurement of tunneling and Heckman two-step selection model.

The results show that DCCC reduces tunneling activities. This negative association is more pronounced for non-state-owned enterprises and firms whose chairmen and CEOs work in the respective hometowns. DCCC restrains tunneling activities through mechanisms by establishing an informal supervisory effect on CEOs because the CEOs fear reputational damage and strengthening cooperation between chairmen and CEOs. Further analyses suggest that this negative association is more significant when chairmen and CEOs are non-controlling shareholders, but the association is weakened during the coronavirus disease 2019 (COVID-19) crisis.

As dialect is a carrier of culture, this study's results imply that cultural proximity can replace formal mechanisms to enhance corporate governance.

Under the repeated action of the construction load, opening deformation and disturbed deformation occurred at the precast box culvert joints of the shield tunnel. The objective of this paper is to investigate the effect of construction vehicle loading on the mechanical deformation characteristics of the internal structure of a large-diameter shield tunnel during the entire construction period.

The structural response of the prefabricated internal structure under heavy construction vehicle loads at four different construction stages (prefabricated box culvert installation, curved lining cast-in-place, lane slab installation and pavement structure casting) was analyzed through field tests and ABAQUS (finite element analysis software) numerical simulation.

Heavy construction vehicles can cause significant mechanical impacts on the internal structure, as the construction phase progresses, the integrity of the internal structure with the tunnel section increases. The vertical and horizontal deformation of the internal structure is significantly reduced, and the overall stress level of the internal structure is reduced. The bolts connecting the precast box culvert have the maximum stress at the initial stage of construction, as the construction proceeds the stress distribution among the bolts gradually becomes uniform.

This study can provide a reference for the design model, theoretical analysis and construction technology of the internal structure during the construction of large-diameter tunnel projects.

The authors study and compare the effects of three CEO compensation restricting policies issued by the Chinese government in 2009, 2012 and 2015. This paper aims to shed light on the conditions under which CEO compenstation can be effectively regulated without negatively affecting firm performance.

These policies targeted state-owned enterprises (SOEs), especially central state-owned enterprises (CSOEs). Using these policies as natural experiments, the authors investigate how their effects differ on CEO compensation, firm performance and two known performance-decreasing mechanisms: perk consumption and tunneling activities.

The authors show that restricting CEO pay does not necessarily backfire in terms of deteriorating firm performance. This non-decreasing firm performance can be achieved by restricting perk consumption and tunneling activities while introducing CEO pay regulations.

The authors exploit a powerful experimental setting in the context of China. The evidence contributes to the literature on CEO pay regulations and is relevant to the managerial decisions of policy makers and boards of directors.

This work aims to demonstrate the feasibility of fully preserving the historical heritage at the same time reordering the cities and their traffic.

This paper describes the sustainable solution designed for the landscape change required and to maintain the bridge integrity by excavating under the pier with the maintenance of traffic during its execution.

It is concluded that the elimination of urban motorways on the surface often leads to the excavation of tunnels under the existing buildings, with little coverage in most of them. This complicates the implementation of burials in cities with an important historical heritage, which must be given conservation priority in the choice of technical solutions.

The Segovia Bridge over the Manzanares River, the oldest bridge in Madrid, was built in the 16th century. With the burial of the M-30 motorway, it has been necessary to build a tunnel immediately under one of the bridge piers, practically without lining between the foundations and the upper slab of the tunnel.

The purpose of the study is to examine how operating efficiencies from incentive alignment compensate for rent extraction in family firms. The author asks whether ownership (1) improves operating efficiencies to increase firm value, (2) positively affects related-party transactions (RPTs), or (3) destroys firm value. Finally, the author assesses whether the incentive effect dominates the entrenchment effect.

This study employs a panel of 333 listed family firms (and 185 nonfamily firms) and handles endogeneity using a dynamic panel system GMM and panel VAR.

Ownership decreases discretionary expenses and increases asset utilization to add firm value. The efficiency gains generate more value in family firms, especially majority-held ones, than in nonmajority ones. However, ownership is also related to increased RPTs (especially dubious loans/guarantees), reducing firm value. RPTs destroy value more severely in the family (or group) firms than in nonfamily (nongroup) firms. It could be why ownership's positive impact on value is lower in family firms than in nonfamily firms. Overall, the incentive effect dominates the entrenchment effect and is robust to controlling private benefits of control in the dynamic ownership-value model.

(1) A family firm's ownership may not be optimal. (2) The firm's long-term commitment as a dynasty limits the scale of expropriation yet sustains impetus for long-term value creation. The paradox partly explains why large family holdings and firm-specific investments endure over generations. (3) This way, large ownership substitutes weak investor protection in India despite tunneling as skin in the game provides necessary investor confidence. (4) Future studies can examine whether extraction varies with family generations and how family characteristics affect the incentive effects.

(1) Concentrated ownership may not be a wrong policy choice in emerging markets to draw firm-specific investments. (2) Investors, auditors, or creditors must pay closer attention to loans/guarantees. (3) More vigorous enforcement, auditor scrutiny, and board oversight are needed.

Family firms are not necessarily a bad organization type that destroys investor wealth. They can be valuably efficient due to their ownership and wealth concentration, and frugality. They matter in the economic growth of a developing market like India.

(1) Extends ownership-performance research to family firms and shows that although ownership facilitates tunneling, the incentive effect dominates; (2) family ownership is not impacted by firm value; (3) family ownership levels reduce discretionary expenses and increase asset utilization to create added value, especially in majority-held family firms; (4) RPTs and loans/guarantees increase with ownership; (5) value erosion from RPTs is higher in family (group) firms than in other firms.

High packaging density in the present VLSI era builds an acute power crisis, which limits the use of MOSFET device as a constituent block in CMOS technology. This leads researchers in looking for alternative devices, which can replace the MOSFET in CMOS VLSI logic design. In a quest for alternative devices, tunnel field effect transistor emerged as a potential alternative in recent times. The purpose of this study is to enhance the performances of the proposed device structure and make it compatible with circuit implementation. Finally, the performances of that circuit are compared with CMOS circuit and a comparative study is made to find the superiority of the proposed circuit with respect to conventional CMOS circuit.

Silicon–germanium heterostructure is currently one of the most promising architectures for semiconductor devices such as tunnel field effect transistor. Analytical modeling is computed and programmed with MATLAB software. Two-dimensional device simulation is performed by using Silvaco TCAD (ATLAS). The modeled results are validated through the ATLAS simulation data. Therefore, an inverter circuit is implemented with the proposed device. The circuit is simulated with the Tanner EDA tool to evaluate its performances.

The proposed optimized device geometry delivers exceptionally low OFF current (order of 10^−18 A/um), fairly high ON current (5x10^−5 A/um) and a steep subthreshold slope (20 mV/decade) followed by excellent ON–OFF current ratio (order of 10^13) compared to the similar kind of heterostructures. With a very low threshold voltage, even lesser than 0.1 V, the proposed device emerged as a good replacement of MOSFET in CMOS-like digital circuits. Hence, the device is implemented to construct a resistive inverter to study the circuit performances. The resistive inverter circuit is compared with a resistive CMOS inverter circuit. Both the circuit performances are analyzed and compared in terms of power dissipation, propagation delay and power-delay product. The outcomes of the experiments prove that the performance matrices of heterojunction Tunnel FET (HTFET)-based inverter are way ahead of that of CMOS-based inverter.

Germanium–silicon HTFET with stack gate oxide is analytically modeled and optimized in terms of performance matrices. The device performances are appreciable in comparison with the device structures published in contemporary literature. CMOS-like resistive inverter circuit, implemented with this proposed device, performs well and outruns the circuit performances of the conventional CMOS circuit at 45-nm technological node.

This paper aims to describe a proposal for an innovative method of normal shock wave–turbulent boundary layer interaction (SBLI) and shock-induced separation control.

The concept is based on the introduction of a tangentially moving wall upstream of the shock wave and in the interaction region. The SBLI control mechanism may be implemented as a closed belt floating on an air cushion, sliding over two cylinders and forming the outer skin of the suction side of the airfoil. The presented exploratory numerical study is conducted with SPARC solver (steady 2D RANS). The effect of the moving wall is presented for the NACA 0012 airfoil operating in transonic conditions.

To assess the accuracy of obtained solutions, validation of the computational model is demonstrated against the experimental data of Harris, Ladson & Hill and Mineck & Hartwich (NASA Langley). The comparison is conducted not only for the reference (impermeable) but also for the perforated (permeable) surface NACA 0012 airfoils. Subsequent numerical analysis of SBLI control by moving wall confirms that for the selected velocity ratios, the method is able to improve the shock-upstream boundary layer and counteract flow separation, significantly increasing the airfoil aerodynamic performance.

The moving wall concept as a means of normal shock wave–turbulent boundary layer interaction and shock-induced separation control has been investigated in detail for the first time. The study quantified the necessary operational requirements of such a system and practicable aerodynamic efficiency gains and simultaneously revealed the considerable potential of this promising idea, stimulating a new direction for future investigations regarding SBLI control.

The purpose of this study is to propose a precise and standardized strategy for numerically simulating vehicle aerodynamics.

Error sources in computational fluid dynamics were analyzed. Additionally, controllable experiential and discretization errors, which significantly influence the calculated results, are expounded upon. Considering the airflow mechanism around a vehicle, the computational efficiency and accuracy of each solution strategy were compared and analyzed through numerous computational cases. Finally, the most suitable numerical strategy, including the turbulence model, simplified vehicle model, calculation domain, boundary conditions, grids and discretization scheme, was identified. Two simplified vehicle models were introduced, and relevant wind tunnel tests were performed to validate the selected strategy.

Errors in vehicle computational aerodynamics mainly stem from the unreasonable simplification of the vehicle model, calculation domain, definite solution conditions, grid strategy and discretization schemes. Using the proposed standardized numerical strategy, the simulated steady and transient aerodynamic characteristics agreed well with the experimental results.

Building upon the modified Low-Reynolds Number k-e model and Scale Adaptive Simulation model, to the best of the authors’ knowledge, a precise and standardized numerical simulation strategy for vehicle aerodynamics is proposed for the first time, which can be integrated into vehicle research and design.

The paper explores the roles of involved organizations in the designation of Batu Arang in Gombak, Selangor, Malaysia, as the Coal Mining and Geological Heritage Site, the heritage significance selected as the elements of its designation and the challenges faced by the involved stakeholders during the designation process.

The primary research material is derived from the documentation review on the final draft of the Special Area Plan (RKK) of Batu Arang and the final draft of the Geopark Management Plan, field investigation on the heritage significances and interviews with the involved organizations: the Selayang Municipal Council (MPS), the State of Selangor Malay Custom and Heritage Corporation (PADAT) and the Village Community Management Council (MPKK) of Batu Arang.

This paper found that Batu Arang has the potential to be developed as an important heritage mining site and heritage tourism destination; however, many of the heritage significances are being demolished, invaded and abandoned due to human aggression or effects of nature. In addition, it reveals the roles of each involved organization, issues that occurred and challenges faced by the organizations during the designation process as a heritage site, namely in terms of management, property ownership and promotion.

The paper outlines that a heritage mining site like Batu Arang should be considered an important heritage as well as other heritage sites in Malaysia, and issues and challenges faced during the designation process should be discussed critically to ensure that these heritage significances will not be neglected and abandoned.