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Seismometers continuously record a wide range of ground movements not caused by earthquake activity, but rather generated by human activities such as traffic, industrial machinery functioning and industrial processes. In this Chapter we exploit seismic data to predict variations in Gross Domestic Product (GDP) for a set of States in the USA over the period from 2016 to 2021. We measure the noise generated at specific frequencies that are linked to human activity and use it as an indicator of economic activity. We show a remarkable reduction in seismic noise due to a slowdown in traffic and economic activities during the Corona economic crisis. Our results point at seismic data as a valuable source of information that can be used for monitoring regional and national economies.

The purpose of this paper is to study the effects of viscoelastic links between two adjacent buildings for pounding mitigation under white-noise seismic input.

A formulation is first extracted for the effective modal damping ratios of the system. Then, two single DOF linear buildings connected by viscoelastic links are considered with both classical and non-classical damping schemes. The inelastic behavior is also taken into account by using equivalent natural frequencies and damping ratios of the buildings. The effect of ground dominant frequency and damping on the displacement response is also investigated by using Kanai‒Tajimi filtered white noise as the random input.

The difference between classical and non-classical damping is shown to be less than 20 percent, implying the permission in using the simpler classical damping scheme. Finally, the problem is extended to two-storey buildings, where using viscoelastic links only at the top story level of the buildings is shown to be sufficient for controlling individual, as well as relative, motions of the structures.

Results demonstrate that the use of link with a moderate stiffness may reduce the stiffer building displacement up to approximately 20 percent in comparison to the free displacement, while the seismic pounding of the adjacent buildings is effectively controlled. Further, an upper limit of link stiffness is obtained for preventing the increase in the stiffer building displacement, which may be exceeded by the minimum link stiffness necessary for pounding prevention if small gap size exists.

The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China, which is based on P-wave earthquake early-warning and multiple ways of rapid treatment.

The paper describes the key technologies that are involved in the development of the system, such as P-wave identification and earthquake early-warning, multi-source seismic information fusion and earthquake emergency treatment technologies. The paper also presents the test results of the system, which show that it has complete functions and its major performance indicators meet the design requirements.

The study demonstrates that the high speed railways earthquake early-warning system serves as an important technical tool for high speed railways to cope with the threat of earthquake to the operation safety. The key technical indicators of the system have excellent performance: The first report time of the P-wave is less than three seconds. From the first arrival of P-wave to the beginning of train braking, the total delay of onboard emergency treatment is 3.63 seconds under 95% probability. The average total delay for power failures triggered by substations is 3.3 seconds.

The paper provides a valuable reference for the research and development of earthquake early-warning system for high speed railways in other countries and regions. It also contributes to the earthquake prevention and disaster reduction efforts.

Viscous dampers are commonly used in large span cable-stayed bridges to mitigate seismic effects and have achieved great success.

However, the nonlinear analysis on damper parameters is usually computational intensive and nonobjective. To address these issues, this paper proposes a simplified method to determine the viscous damper parameters for double-tower cable-stayed bridges. An empirical formula of the equivalent damping ratio of viscous dampers is established through decoupling nonclassical damping structures and linearization of nonlinear viscous dampers. Shaking table tests are conducted to verify the feasibility of the proposed method. Moreover, this simplified method has been proved in long-span cable-stayed bridges.

The feasibility of this method is verified by the simplified model shaking table test. This simplified method for determining the parameters of viscous dampers is verified in cable-stayed bridges with different spans.

This simplified method has been validated in cable-stayed bridges with various spans.

The lecture attacks a fifty‐year‐old paradigm which claims that “information” (as the term is understood by Communication Engineers) cannot have any moral or economic value. We shall show by a Monte Carlo simulated oil‐exploration study how this paradox disappears in the Islamic Interactive, Integrative and Evolutionary (IIE) world model. In the IIE exploration model, information is used to lead to more profit, and (part of) the profit is utilised to gain information.

The paper attacks a fifty‐years‐old paradox, which has claimed that “information” (as the term is understood by Communication Engineers) cannot have any moral or economic value. We shall show by a Monte Carlo simulated oil‐exploration study how this paradox disappears in the Islamic Interactive, Integrative and Evolutionary (IIE) world model. In the IIE exploration model, information is used to lead to more profit, and (part of) the profit is utilized to gain information.

This study aims to perform the experimental work on a laboratory-constructed steel truss bridge model on which hammer blows are applied for excitation. The vibration response signals of the bridge structure are collected using sensors placed at different nodes. The different damaged states such as no damage, single damage, double damage and triple damage are introduced by cutting members of the bridge. The masked noise with recorded vibration responses generates challenge to properly analyze the health of bridge structure.

The analytical modal properties are obtained from finite element model (FEM) developed using SAP2000 software. The response signals are analyzed in frequency domain by power spectrum and in time-frequency domain using spectrogram and Stockwell transform. Various low pass signal-filtering techniques such as variational filter, lowpass sparse banded (AB) filter and Savitzky–Golay (SG) differentiator filter are also applied to refine vibration signals. The proposed methodology further comprises application of Hilbert transform in combination with MUSIC and ESPRIT techniques.

The outcomes of SG filter provided the denoised signals using appropriate polynomial degree with proper selected window length. However, certain unwanted frequency peaks still appeared in the outcomes of SG filter. The SG-filtered signals are further analyzed using fused methodology of Hilbert transform-ESPRIT, which shows high accuracy in identifying modal frequencies at different states of the steel truss bridge.

The sequence of proposed methodology for denoising vibration response signals using SG filter with Hilbert transform-ESPRIT is a novel approach. The outcomes of proposed methodology are much refined and take less computational time.

The purpose of this study is to systematically review the state-of-art literature on the net-zero economy in the field of supply chain management.

A systematic literature review of 79 articles published from 2009 to 2021 has been conducted to minimise the researchers' bias and maximise the reliability and replicability of the study.

The thematic analysis reveals that studies in the field of net-zero economy have mostly been done on decarbonisation in the supply chain, emission control and life cycle analysis and environmental and energy management. The findings highlight the strong positive association between digitalisation, circular economy and resources optimization practices with net-zero economy goals. The study also addresses the challenges linked with the net-zero economy at the firm and country levels.

Practitioners in companies and academics might find this review valuable as this study reviews, classifies and analyses the studies, outlines the evolution of literature and offers directions for future studies using the theory, methodology and context (TMC) framework.

This is the first study that uses a structured approach to analyse studies done in the net-zero field by assessing publications from 2009 to 2021.

This study aims to reveal the room-temperature effect of a superconducting gravimeter prototype, which will guide its subsequent optimization to improve its gravimetric measurement accuracy.

Without leveling, the prototype output signal, tilt data and room temperature were measured under steady operating conditions. After analyzing the correlations of the three data sets, the residuals of the prototype’s output signal were compensated using the tilt data and the geodynamic effects (ocean tide loading, atmospheric loading and the gravitational effect of polar motion) were then corrected.

The remaining residuals after correction may be caused by small tilt variations that are due to the sensor chamber temperature and radiation shield temperature changes. These small tilt variations were submerged in the tilt signal noise. Although the peak-to-peak noise of the tiltmeter does not exceed 15 µrad, it can still produce gravimetric deviations above 60 µGal when the prototype is significantly tilted.

This study analyzes in detail the room-temperature effect of a superconducting gravimeter prototype, introduces the tilt effect of the relative gravimeters to compensate for the gravimetric deviations and emphasizes that the improvement of fine leveling and the accuracy of the tiltmeter are key requirements for the prototype to perform high-accuracy gravity measurement tasks.