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The study shows that with the progress of building technologies and building materials, the scale of buildings has increased. But in earthquake-prone areas, large-scale buildings mean higher risks; therefore improving the seismic capacity of buildings is an important measure to reduce the risk of buildings.

In this study, the isolation structure of buildings was introduced briefly, and the cost-benefit based optimization model of the isolation structure was constructed. The optimization of the isolation structure was carried out from the perspective of benefit analysis. Then, two buildings with the same structure were analyzed as examples. One kept the original isolation structure, and the other optimized the isolation structure with the optimization model.

The final results showed that the optimized isolation structure had a lower input cost ratio, i.e. it had a higher benefit in the same whole life cycle, and the expected loss cost of the structure produced in the same life cycle was lower.

In conclusion, the optimization model of the isolated structure based on benefit analysis can effectively improve the benefit of building isolation structure produced in the whole life cycle.

The purpose of this paper is to accomplish robust actuator fault isolation and identification for microsatellite attitude control systems (ACSs) subject to a series of space disturbance torques and gyro drifts.

For the satellite attitude dynamics with Lipschitz constraint, a multi-objective nonlinear unknown input observer (NUIO) is explored to accomplish robust actuator fault isolation based on a synthesis of H_inf techniques and regional pole assignment technique. Subsequently, a novel disturbance-decoupling learning observer (D²LO) is proposed to identify the isolated actuator fault accurately. Additionally, the design of the NUIO and the D²LO are reformulated into convex optimization problems involving linear matrix inequalities (LMIs), which can be readily solved using standard LMI tools.

The simulation studies on a microsatellite example are performed to prove the effectiveness and applicability of the proposed robust actuator fault isolation and identification methodologies.

This research includes implications for the enhancement of reliability and safety of on-orbit microsatellites.

This study proposes novel NUIO-based robust fault isolation and D²LO-based robust fault identification methodologies for spacecraft ACSs subject to a series of space disturbance torques and gyro drifts.

The purpose of this paper, a point prevalence study, is to quantify the incidence of isolation and identify the type of communicable diseases in isolation. The paper evaluates isolation precaution communication, availability of personal protective equipment (PPE) as well as other equipment necessary for maintaining isolation precautions.

A standardised audit tool was developed in accordance with the National Standards for the Prevention and Control of Healthcare Associated Infections (May 2009). Data were collected from 14 March 2017 to 16 March 2017, through observation of occupied isolation rooms in an academic hospital in Dublin, Ireland. The data were subsequently used for additional analysis and discussion.

In total, 14 per cent (125/869) of the total inpatient population was isolated at the time of the study. The most common isolation precaution was contact precautions (96.0 per cent). In all, 88 per cent of known contact precautions were due to multi-drug resistant organisms. Furthermore, 96 per cent of patients requiring isolation were isolated, 92.0 per cent of rooms had signage, 90.8 per cent had appropriate signs and 93.0 per cent of rooms had PPE available. Finally, 31 per cent of rooms had patient-dedicated and single-use equipment and 2.4 per cent had alcohol wipes available.

The audit tool can be used to identify key areas of noncompliance associated with isolation and inform continuous improvement and education.

Currently, the rate of isolation is unknown in Ireland and standard guidelines are not established for the evaluation of isolation rooms. This audit tool can be used as an assessment for isolation room compliance.

This paper aims to present the design and implementation of a circularly polarized co-planar waveguide (CPW) fed wideband pie-shaped monopole antenna for multi-antenna techniques. Multi-antenna techniques are promising solutions for higher data rate and enhanced reliability of wireless applications. They find numerous applications in 4G/5G networks and in most wireless standards such as wireless local area networks (WLAN), wireless fidelity and worldwide interoperability for microwave access systems to enhance the channel capacity without additional spectrum by means of multi-path propagation techniques.

The antenna is designed to operate at three WLAN frequency bands of 4.8, 5.2 and 5.8 GHz. The measured 10 dB impedance bandwidth of the proposed antenna element is 1.2 GHz (24.23 per cent). The proposed CPW fed, pie-shaped monopole antenna has a gain of 5.4 dB and an efficiency of 72.8 per cent at 4.8 GHz.

To use the proposed antenna in a multi-antenna environment, the antennas have to be placed in a close proximity to each other. The close proximity introduces strong mutual coupling between the antennas, which in turn degrades the performance of multi-antenna systems. A multi-antenna system with two antenna elements has been constructed with an edge to edge spacing of 0.24 λ₀ (15 mm), and the mutual coupling level is −17 dB. To enhance the isolation between the antenna elements, a shorting pin-based interconnected semicircles enclosed decoupling structure is proposed, which improves the isolation by a factor of 12.67 dB at 4.8 GHz.

To validate the performance of the proposed multi-antenna in working environment, the performance metrics such as envelope correlation coefficient (ECC), diversity gain (DG) and total active reflection coefficient (TARC) are computed for the proposed multiple-input multiple-output (MIMO) antenna. The ECC value is 0.000366 at center frequency and below 0.09 for the entire operating bandwidth, which is well below the acceptable level of 0.5 as per 3GPP standard. The DG value lies above 9.5 dB for the entire operating bandwidths and it is well above the minimum value of 3 dB. The TARC values are calculated based on S parameters, and it proves that the proposed antenna a good candidate for the multi-antenna systems.

This study explores the characteristics of high-speed rail (HSR) and air transportation networks in China based on the weighted complex network approach. Previous related studies have largely implemented unweighted (binary) network analysis, or have constructed a weighted network, limited by unweighted centrality measures. This study applies weighted centrality measures (mean association [MA], triangle betweenness centrality [TBC], and weighted harmonic centrality [WHC]) to represent traffic dynamics in HSR and air transportation weighted networks, where nodes represent cities and links represent passenger traffic. The spatial distribution of centrality results is visualized by using ArcGIS 10.2. Moreover, we analyze the network robustness of HSR, air transportation, and multimodal networks by measuring weighted efficiency (WE) subjected to the highest weighted centrality node attacks. In the HSR network, centrality results show that cities with a higher MA are concentrated in the Yangtze River Delta and the Pearl River Delta; cities with a higher TBC are mostly provincial capitals or regional centers; and cities with a higher WHC are grouped in eastern and central regions. Furthermore, spatial differentiation of centrality results is found between HSR and air transportation networks. There is a little bit of difference in eastern cities; cities in the central region have complementary roles in HSR and air transportation networks, but air transport is still dominant in western cities. The robustness analysis results show that the multimodal network, which includes both airports and high-speed rail stations, has the best connectivity and shows robustness.

The purpose of this paper is to examine the economic viability of a new and innovative seismic damage resisting system (SDRS) device by conducting a feasibility study. The SDRS device has been patented and specifically designed to be implemented in multi-storey modular buildings in seismic regions such as New Zealand.

Using a case study approach, two sample modular multi-storey buildings were purposively selected for the study. A cost-comparison analysis was conducted using the SDRS device in the two buildings, by carrying out a measure and price exercise of the construction elements.

The research results showed that the SDRS device is an economically viable option for mitigating seismic damage in modular multi-storey buildings in New Zealand. There is an average of 7.34 per cent of cost reduction when SDRS is used in modular multi-storey buildings when compared to other seismic resistance systems such as base isolation, moment resisting frames and friction damper systems.

The economic viability of the SDRS presents an opportunity for its usage in modular design and construction of multi-storey buildings. SDRS system is also applicable to other building typologies and construction methods. The use of SDRS also aligns with the current national objective to provide more affordable and resilient housing within a limited time; the opportunity is considered significant in New Zealand, including for export and manufacturing.

The confirmation of the SDRS device’s economic feasibility is the original contribution of the authors.

The purpose of this paper is to examine the association of social avoidance among police, cardiovascular disease (CVD) (metabolic syndrome (MetSyn)), and social support.

Participants were officers from the Buffalo Cardio-Metabolic Occupational Police Stress study (n=289). Social avoidance (defined as the tendency to avoid social contact) and other subscales from the Cook-Medley Hostility Scale were analyzed. The mean number of MetSyn components across tertiles of the Cook-Medley scales was computed using analysis of variance and analysis of covariance. Social support was measured with the Social Provisions Scale, categorized as high or low based on the median.

The mean number of MetSyn components increased significantly across tertiles of social avoidance (1.51±0.18, 1.52±0.12, and 1.81±0.12); the only Cook-Medley subscale that remained significantly associated with MetSyn following adjustment for age and gender. Participants high in social avoidance reported significantly lower social support (79.9±8.5 vs 85.8±8.6; p=0.001).

The study is cross-sectional and therefore precludes causality. The authors were unable to determine the direction of associations between social avoidance and MetSyn. The measure of social support was unidimensional, including only perceived support; additional types of social support measures would be helpful.

This study suggests that occupational-based police social isolation is associated with health outcomes and lower support. Several suggestions are made which will help to improve communication between the police and public. Examples are the use of social media, training in communication techniques, and changing the police role to one of public guardians.

Social avoidance is the least studied the Cook-Medley subscale associated with CVD. It is important for the health of officers to maintain a social connection with others.

The purpose of this paper is to achieve fault reconstruction for reaction wheels in spacecraft attitude control systems (ACSs) subject to space disturbance torques.

Considering the influence of rotating reaction wheels on spacecraft attitude dynamics, a novel non-linear learning observer is suggested to robustly reconstruct the loss of reaction wheel effectiveness faults, and its stability is proven using Lyapunov’s indirect method. Further, an extension of the proposed approach to bias faults reconstruction for reaction wheels in spacecraft ACSs is performed.

The numerical example and simulation demonstrate the effectiveness of the proposed fault-reconstructing methods.

This paper includes implications for the development of reliability and survivability of on-orbit spacecrafts.

This paper proposes a novel non-linear learning observer-based reaction wheels fault reconstruction for spacecraft ACSs.

Using a case study approach, this chapter examines two primary changes to global health education prompted and exacerbated by the COVID-19 pandemic. First, is the acceleration of digital education into the typical global health classroom. Second, is the integration of transnational networks and partnerships between intergovernmental organizations (IGOs), nongovernmental organizations (NGOs), and higher education institutions (HEIs) to create, adapt, and disseminate digital materials in fast-changing information environments. The chapter examines the potential positive and negative impacts of the proliferation of digital content created by IGOs and international NGOs that is being rapidly integrated into use in HEIs for Global Health. The growth of tools and access through these new partnerships may lead to increased access to global health information for professionals. However, these changes may have long-term implications for global health regarding equitable access to culturally appropriate and accurate information. Furthermore, there may be additional implications for equity, as the proliferation of tools may still leave out the most vulnerable that do not have access to digital platforms.

In recent years, three-dimensional (3D) seismic base isolation system has been studied extensively. This paper aims to propose a new 3D combined isolation bearing (3D-CIB) to mitigate the seismic response in both the horizontal and vertical directions.

The new 3D-CIB composed of laminated rubber bearing coupled with combined disk spring bearing (CDSB) was proposed. Comprehensive analysis of constitution and theoretical derivation for 3D-CIB were presented. The advantage of CDSB is that the constitution can be flexibly adjusted according to the requirements of the bearing capacity and vertical stiffness. Hence, four different combinations of CDSB were designed for the 3D-CIB and employed to isolate nuclear reactor building. A comparative study of the seismic response in terms of seismic action, acceleration floor response spectra (FRS), peak acceleration and relative displacement response was carried out.

3D-CIB can effectively reduce seismic action, FRS and peak acceleration response of the superstructure in both the horizontal and vertical directions. Overall, the horizontal isolation effectiveness of 3D-CIB was slightly influenced by vertical stiffness. The decrease in the vertical stiffness of the 3D-CIB can reduce the vertical FRS and shift the peak values to a lower frequency. The vertical peak acceleration decreased with a decrease in the vertical stiffness. The superstructure exhibited a rocking effect during the earthquake, and the decrease in the vertical stiffness may increase the rocking of the superstructure.

Although the advantage of 3D-CIB is that the vertical stiffness can be flexibly adjusted by different constitutions, the vertical stiffness should be designed by properly accounting for the balance between the isolation effectiveness and displacement response. This study of isolation effectiveness can provide the technical basis for the application of 3D-CIB into real engineering of nuclear power plants.