Advancing Shallow Tunnel Construction in Soft Ground: The Pipe-Umbrella Box Jacking Method

The development of modern cities has often led to increased traffic congestion and limited usable space. One effective solution to these problems is to construct roadway tunnels, which can expand urban space and alleviate traffic congestion. However, building large underpass tunnels in urban areas, especially in soft ground, presents...

A state-of-art review on development and progress of backfill grouting materials for shield tunneling

Backfill grouting plays a vital role in shield tunneling. This paper aims to present a comprehensive review of the development and progress of backfill grouting materials specifically designed for shield tunneling. Initially, the various components of grouts, such as pozzolanic materials, filling fine aggregates, and chemical additives, are...

A safety investment optimization model for power grid enterprises based on System Dynamics and Bayesian network theory

In recent years, frequent large-scale power grid accidents have caused serious economic losses and bad social impact, which has drawn great attention from power grid enterprises. As one of the key elements of production, safety investment plays an important role in improving the safety level and reducing accident loss. In this paper, System...

Case Study of the Largest Concrete Earth Pressure Balance Pipe-Jacking Project in the World

Pipe jacking has been the dominant trenchless technology for constructing small (\2 m) to medium-diameter (\4 m) tunnels. Uncertainties and construction difficulties increase significantly when the diameter of the tunnel exceeds 4 m. This paper presents a case study of the largest concrete pipe-jacking tunnel project in the world, the...

Wireless, implantable catheter-type oximeter designed for cardiac oxygen saturation

Accurate, real-time monitoring of intravascular oxygen levels is important in tracking the cardiopulmonary health of patients after cardiothoracic surgery. Existing technologies use intravascular placement of glass fiber-optic catheters that pose risks of blood vessel damage, thrombosis, and infection. In addition, physical tethers to power...

Parameter optimization of environmental technologies using a LCA-based analysis scheme: A bioaugmentation case study

Life cycle assessment (LCA) has proven to be a useful tool in assessing environmental technologies in a retrospective manner. To fully uncover the environmental improvement potential while advancing technologies under technical and environmental constraints, this study recommended approaching the LCA proactively to assess the progress of...

Control Design, Stability Analysis, and Traffic Flow Implications for Cooperative Adaptive Cruise Control Systems with Compensation of Communication Delay

Communication delay is detrimental to the performance of cooperative adaptive cruise control (CACC) systems. In this paper, we incorporate communication delay explicitly into control design and propose a delay-compensating CACC. In this new CACC system, the semi-constant time gap (Semi-CTG) policy, which is modified on the basis of the widely...

Fast and robust low-rank approximation for five-dimensional seismic data reconstruction

Five-dimensional (5D) seismic data reconstruction becomes more appealing in recent years because it takes advantage of five physical dimensions of the seismic data and can reconstruct data with large gap. The low-rank approximation approach is one of the most effective methods for reconstructing 5D dataset. However, the main disadvantage of...

Fully controlled photonic spin in highly confined optical field

As an intrinsic attribute of light, the spin angular momentum (SAM) of photons has aroused considerable attention because of the fascinating properties emerging from light–matter interactions. We show that a diffraction-limited focal field with a steerable photonic spin structure in three dimensions can be produced under a 4π microscopic...

Life cycle assessment in wastewater treatment:: Influence of site-oriented normalization factors, life cycle impact assessment methods, and weighting methods

This present study aims to analyze the differences in results of different site-directional life cycle assessment<br/>(LCA) methods applied in the field of wastewater treatment. Site-generic methods were employed and<br/>compared with China-specific methods on a full-scale wastewater treatment case. A set of Chinese<br/>normalized factors were...