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In this special issue of IEEE Transactions on Visualization and Computer Graphics (TVCG), we are pleased to present a subset of papers from the 29th IEEE Conference on Virtual Reality and 3D User Interfaces (IEEE VR 2022), held virtually March 12-16, 2022, in Christchurch, New Zealand. [ABSTRACT FROM AUTHOR]

During the last decades, liquefaction damages induced by earthquakes have underlined the importance of identifying effective soil improvement techniques for mitigation purposes. Vibratory methods, such as rammed aggregate piers, are commonly used to densify sands and silty sands, erroneously neglecting the influence of the lateral stress. This paper presents the results of a series of liquefaction mitigation case studies carried out using rammed aggregate piers in Christchurch (New Zealand), Boca de Briceño (Ecuador), and Bondeno (Italy) following the 2010–2011 Canterbury seismic sequence, the 2016 Muisne earthquake, and the 2012 Emilia seismic sequence, respectively. The availability of coupled piezocone and seismic dilatometer tests before and after treatment enabled a geotechnical characterization of the three sandy sites to be made, along with estimating the at-rest lateral earth pressure coefficient, and comparing the effectiveness of the treatment at the trial sites. Finally, the paper proposes an updated procedure for liquefaction assessment that takes into account both the increase in soil density and lateral stress produced by ground improvement. [ABSTRACT FROM AUTHOR]

Copyright of Social & Cultural Geography is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There has been a long-standing yet largely unreported intersection between video-gaming and violent extremism, spanning across jihadist, far-right, and other types of ideologies. Within this framework, until late, scant attention has been paid to the concept of "gamification"; i.e. the application of gaming and game-design principles within non-gaming environments. This paper contributes to this newly emerging area of study by exploring the theoretical underpinnings of gamification and applying these principles to a prominent empirical example: the Christchurch attack in New Zealand in 2019. With a particular focus on the ("setup," "rule," and "progression") "mechanics" of gamification, this article explores two aspects. The first considers how the assailant (intentionally or otherwise) designed and constructed the game; undertaken through an empirical analysis of their manifesto, live-stream video, and original post on the imageboard 8chan (or Infinite Chan). This will be complimented by the second aspect which explores how the game was, in turn, "gamified" through audience reaction to and interaction on the original 8chan post. The article concludes by discussing whether the gamification of the Christchurch attack serves as a framework for future attacks. [ABSTRACT FROM AUTHOR]

Welcome to the 11 th IEEE Transactions on Visualization and Computer Graphics (TVCG) special issue on IEEE Virtual Reality and 3D User Interfaces. This volume contains a total of 29 full papers selected for and presented at the IEEE Conference on Virtual Reality and 3D User Interfaces (IEEE VR 2022), held fully virtual in Christchurch, New Zealand from March 12 to 16, 2022. [ABSTRACT FROM AUTHOR]

INTRODUCTION: This paper is the second of two (Briggs et al., 2023) detailing the outcome of a mixed-method study examining the mental health and wellbeing of a randomised sub-sample of 60 clients who attended the Canterbury Charity Hospital Trust Counselling Service following the earthquake that struck Christchurch on 22 February 2011. METHODS: This paper focuses on the results from semi-structured interviews with the study participants. Open-ended questions explored: 1) secondary stressors that impacted participant wellbeing; and 2) experiences of counselling at the CCHT. FINDINGS: The findings highlight several secondary stressors for participants including practical and financial assistance, social contacts, and disrupted employment and education, all of which continued to impact on their wellbeing. The experience of counselling varied with mixed views on its value, the skills of the counsellors, and the benefit of having counselling with a practitioner who had also experienced the traumatic event. CONCLUSIONS: Overall, the initial counselling was viewed as a positive contributor to the participants' recovery, however practitioners, including social workers who offer counselling services, must be mindful of shared trauma, demonstrate emotional regulation, and have relevant knowledge and strategies for a range of client interactions. Continuing professional education, such as webinars and involvement in communities of practice on post-disaster social work practice, are recommended so social workers can better understand the longer-term impacts of disasters and equip themselves for future disaster-related practice. [ABSTRACT FROM AUTHOR]

The paper explores a user-centred methodology for collecting, categorising, visualising, and interpreting data on urban cycling infrastructure and related cycling events. It develops a mobile mixed methods approach combining audio, video, sensor, and geospatial data sources. The method responds to stakeholders' feedback and related concerns about negotiating engineering, landscape and urban design, planning and policy elements in a way that addresses cyclists' needs. It is tested in a pilot study that combines infrastructure monitoring and perception data collection on eight newly built Major Cycle Routes in Christchurch, New Zealand. Data from one Major Cycle Route is used to explore methods of data categorisation, visualisation and interpretation. Based on the results of the pilot study, the paper discusses potential methodological changes or additions. It suggests future research opportunities and potential applications of the proposed methodology to support stakeholders' efforts to advance the planning, design and implementation of urban cycleways. [ABSTRACT FROM AUTHOR]

Copyright of Urban Studies (Sage Publications, Ltd.) is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper investigates the impact of an earthquake on households' perception of the seismic risks associated with residential locations—and, consequently, the impact of this change in perceptions on real estate prices—by performing revealed preference analysis on a unique data set of house prices and damage claims after the 2010/2011 Canterbury earthquake in New Zealand. We show that both informational and heuristic obstacles could have caused households to underestimate location earthquake risk before the quake and overreact to it after the quake. Our findings highlight the importance of quake-related information for seismic risk management and are robust to households' risk preferences in neighborhood propensity score matching. [ABSTRACT FROM AUTHOR]

Climate change and population growth will increase vulnerability to natural and human-made disasters or pandemics. Longitudinal research studies may be adversely impacted by a lack of access to study resources, inability to travel around the urban environment, reluctance of sample members to attend appointments, sample members moving residence and potentially also the destruction of research facilities. One of the key advantages of longitudinal research is the ability to assess associations between exposures and outcomes by limiting the influence of sample selection bias. However, ensuring the validity and reliability of findings in longitudinal research requires the recruitment and retention of respondents who are willing and able to be repeatedly assessed over an extended period of time. This study examined recruitment and retention strategies of 11 longitudinal cohort studies operating during the Christchurch, New Zealand earthquake sequence which began in September 2010, including staff perceptions of the major impediments to study operations during/after the earthquakes and respondents' barriers to participation. Successful strategies to assist recruitment and retention after a natural disaster are discussed. With the current COVID-19 pandemic, longitudinal studies are potentially encountering some of the issues highlighted in this paper including: closure of facilities, restricted movement of research staff and sample members, and reluctance of sample members to attend appointments. It is possible that suggestions in this paper may be implemented so that longitudinal studies can protect the operation of their research programmes. [ABSTRACT FROM AUTHOR]

Twitter analysis through data mining, text analysis, and visualization, coupled with the application of actor-network-theory, reveals a coalition of heterogenous religious affiliations around grief and fascination. While religious violence has always existed, the prevalence of social media has led to an increase in the magnitude of discussions around the topic. This paper examines the different reactions on Twitter to violence targeting three religious communities: the 2015 Charleston Church shooting, the 2018 Pittsburgh Synagogue shooting, and the 2019 Christchurch Mosque shootings. The attacks were all perpetrated by white nationalists with firearms. By analyzing large Twitter datasets in response to the attacks, we were able to render visible associations among actors across religions communities, national identities, and political persuasions. What this project revealed is that if we apply actor-network-theory and data visualization to look at networks created by human/non-human (text, computer, phone, meme, tweet, retweet, hashtag) actors, we can see that knowledge, empathy, and fascination drive communication around mass violence against religious communities. [ABSTRACT FROM AUTHOR]

This paper develops a tsunami inundation model, filling the current void between industry applied simplified methods (bathtub and attenuation) and comprehensive numerical modeling. The proposed model utilizes two‐dimensional equations established on hydraulic principles (energy conservation and friction loss) to produce the finite‐difference, two‐dimensional model. While the sophistication of depth‐averaged numerical modeling has not been entirely replicated, the incorporation of hydraulic roughness and gravitational effects (slope) through the Bernoulli energy equation, accompanied by suitable assumptions, significantly improves performance over simplified bathtub and attenuation methods. This improvement not only retains excellent efficiency (completing case studies in under 100 s) but also yields inundation results comparable to traditional numerical modeling, which typically takes multiple hours to days. This is the first application of such equations to a two‐dimensional tsunami inundation model, leading to simulations at Gisborne and Christchurch, New Zealand, for validation against the numerical model, COMCOT. F1 scores produced from inundation extent comparisons were upwards of 84%. Inundation depth discrepancies recorded 77% within a ±$\pm$1 m range, while over 93% within a ±$\pm$2 m range. [ABSTRACT FROM AUTHOR]

The emergence of the alt-right in the US since 2008 has been widely documented but its international impacts have received less attention. Located in the context of the 2019 Christchurch massacre of 51 people by an Australian alt-right influenced gunman and based in analysis of two Australian forums, XYZ.net.au and #DingoTwitter, this article investigates the transnational spread of alt-right discourse in the context of the platformisation of extremism. Through historical and content analysis of the sites, the paper shows how key alt-right ideologies of 'white replacement' and 'white genocide', along with anti-Semitic and misogynist ideologies, are adapted to local contexts by alt-right influenced actors. Platform logics, it is argued, provide new possibilities for the mutation and spread of 'translocal whiteness' and for the deployment of alt-right 'metapolitical' strategies that seek to normalise racist discourse. [ABSTRACT FROM AUTHOR]

Aotearoa New Zealand's population is ageing. Increasing life expectancy is accompanied by increases in prevalence of Alzheimer's Disease (AD) and ageing-related disorders. The multicentre Dementia Prevention Research Clinic longitudinal study aims to improve understanding of AD and dementia in Aotearoa, in order to develop interventions that delay or prevent progression to dementia. Comprising research clinics in Auckland, Christchurch and Dunedin, this multi-disciplinary study involves community participants who undergo biennial investigations informed by international protocols and best practice: clinical, neuropsychological, neuroimaging, lifestyle evaluations, APOE genotyping, blood collection and processing. A key research objective is to identify a 'biomarker signature' that predicts progression from mild cognitive impairment to AD. Candidate biomarkers include: blood proteins and microRNAs, genetic, neuroimaging and neuropsychological markers, health, cultural, lifestyle, sensory and psychosocial factors. We are examining a range of mechanisms underlying the progression of AD pathology (e.g. faulty blood–brain barrier, excess parenchymal iron, vascular dysregulation). This paper will outline key aspects of the Dementia Prevention Research Clinic's research, provide an overview of data collection, and a summary of 266 participants recruited to date. The national outreach of the clinics is a strength; the heart of the Dementia Prevention Research Clinics are its people. [ABSTRACT FROM AUTHOR]

In this paper probabilistic models are developed for estimating the peak excess pore pressure ratio ( r u ) and peak shear strain ( γ max ), which control liquefaction triggering, in layered granular soils under earthquake loading. The models are developed using non-linear regression applied to a database of 167 352 results from one-dimensional, non-linear, effective stress, site response analyses. A pseudo-parametric regression strategy is adopted to account for the theoretical upper bound on r u at a value of 1. The models include the influence of variables that are specific to the individual layer, to the soil profile and to the ground motion, as well as layer-to-layer interaction and the relationship between r u and γ max . The variability around model predictions is decomposed, and the relative contributions of layer-, profile- and ground motion-specific parameters are evaluated. Epistemic uncertainty related to soil model selection, calibration and validation is also addressed. The total uncertainty around model predictions ranges from 0·5 to 1·6 in natural log units, with smaller values for scenarios that are of particular engineering interest (e.g. high r u ). Finally, the proposed models are used to estimate the probability of liquefaction triggering for case studies from the 2010–2011 Canterbury earthquake sequence. The results are shown to compare favourably with existing deterministic and probabilistic methods in terms of their ability to distinguish between cases where liquefaction was observed in both the Darfield and Christchurch earthquakes and those where no liquefaction was observed in either event. [ABSTRACT FROM AUTHOR]

Court proceedings against the alleged perpretrator of the Christchurch mosque attacks in 2019 led to what may be ground-breaking cooperation between the judicial system and the media to balance fair trial rights and a determination to (a) avoid retraumatisation and (b) prevent the court being used as a platform for white supremacist propaganda. The case, and the willingness of media to honour these imperatives, demonstrates the centrality of publicity in acts of terrorism known as 'propaganda of the deed'. The research outlined in this article suggests that institutional cooperation can avoid 'giving oxygen' to perpetrators and their causes without sacrificing journalistic integrity or a duty to bear witness in the interests of open justice. A change of plea resulted in proceedings being limited to a sentencing hearing. A lengthy trial may have tested the robustness of the measures put in place but, nonetheless, the planning processes employed in New Zealand lead to a conclusion that they could provide a basis for similar cooperation in other judicial jurisdictions, such as Australia. [ABSTRACT FROM AUTHOR]

This paper presents a new framework for the seismic loss prediction of residential buildings in Ōtautahi / Christchurch, New Zealand. It employs data science techniques, geospatial tools, and machine learning (ML) trained on insurance claims data from the Earthquake Commission (EQC) collected following the 2010–2011 Canterbury earthquake sequence (CES). The seismic loss prediction obtained from the ML model is shown to outperform the output from existing risk analysis tools for New Zealand for each of the main earthquakes of the CES. In addition to the prediction capabilities, the ML model delivered useful insights into the most important features contributing to losses during the CES. ML correctly highlighted that liquefaction significantly influenced building losses for the 22 February 2011 earthquake. The results are consistent with observations, engineering knowledge, and previous studies, confirming the potential of data science and ML in the analysis of insurance claims data and the development of seismic loss prediction models using empirical loss data. [ABSTRACT FROM AUTHOR]

More than a decade since the 22 February 2011 earthquake devastated Christchurch CBD, partially demolished and neglected buildings remain present in the post-earthquake landscape. Christchurch City Council has made significant progress in recent years to reduce the level of neglected buildings across the central parts of the city. To encourage remediation of these buildings, the Council initiated the Barrier Sites programme to keep track of central city sites. This paper documents the current inventory of derelict properties and investigates issues that are delaying progress on these sites. We explore regulatory levers that can be used to influence action on these buildings (e.g. provisions in the Building Act and council bylaws). We also investigate how the local market drivers influence the speed of regeneration. Our review identifies gaps in the regulatory powers to act on barrier sites. Taking action involves meeting difficult definitions and tests under legislation and/or taking court proceedings. Specific legislative tools are needed to provide Councils with the powers they need to ensure action is taken on barrier sites to progress the regeneration of the city after a disaster. We also find that the delays in removing the cordon and uncertainties of the public sector anchor projects contained in the Blueprint have led to the loss of private investment and forced central city developments compete with more affordable commercial and residential offerings outside the CBD. With the passing of the 10-year anniversary of the earthquakes, this project offers a timely reminder of the mammoth struggles that the city has overcome evident in the numerous modern and resilient buildings, yet a few ‘battle sites’ slow the much-needed regeneration towards a resilient city centre. [ABSTRACT FROM AUTHOR]

This paper examines restaurant managements' (owners, managers, or the chefs) perceptions, motivations, and constraints in buying local food ingredients from local farmers' market vendors (farmer vendors) in a study conducted in Vancouver, Canada and Christchurch, New Zealand. Semi-structured interviews were conducted with restaurants (31 in Vancouver and 28 in Christchurch). Results revealed that purchasing local food from farmers' market vendors was perceived as beneficial by restaurants, but they experienced challenges with purchasing. This study further presented evidence that restaurants satisfaction with wholesale distributors is an important purchasing factor in local food purchasing decisions while sustainable production products were not the main motivation among restaurants in both the samples. In the light of empirical findings, theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

This paper analyses the impact of a series of mass shootings committed in 2018–2019 by right-wing extremists on 8chan/pol, a prominent far-right online forum. Using computational methods, it offers a detailed examination of how attacks trigger shifts in both forum activity and content. We find that while each shooting is discussed by forum participants, their respective impact varies considerably. We highlight, in particular, a 'Tarrant effect': the considerable effect Brenton Tarrant's attack of two mosques in Christchurch, New Zealand, had on the forum. Considering the rise in far-right terrorism and the growing and diversifying online far-right ecosystem, such interactive offline-online effects warrant the attention of scholars and security professionals. [ABSTRACT FROM AUTHOR]

This paper reports the partial findings of in-depth life history interviews undertaken with three women who have received the Domestic Purposes Benefit (a benefit for single parents and their children) for most of the past five years, who live in poor-quality double-storied state units in Aranui, the poorest part of Christchurch. The research presented here is part of a larger study that seeks to understand and explain why these women, these families are 'at the bottom of the heap'. Part of the rationale for choosing the particular housing structures in this area are that they are universally hated. My theory was that the families living in these units do so by default, because others have been able to negotiate their ways out of these units. Those left are thus the choiceless, the powerless. Now part of the way through my interviews I am not sure that this is the case, although certainly these families have limited choices. This paper has been structured into three parts. The first part provides an overview of the literature which demonstrates the relationship between low income and poor health, educational and social outcomes. The second part recounts what Kath, Mary and Kim (not their real names) said about their own educational experiences. The final section considers the education of the children of these families in terms of aspirations, support and poverty issues. The conclusion looks at the implications for practitioners. [ABSTRACT FROM AUTHOR]

Following the extensive damage to Christchurch's infrastructure in the 2010 and 2011 Canterbury earthquakes, a complete rebuild of the city centre has been undertaken, with a particular focus on seismic- resilient buildings. This paper explores the application of different seismic-resilient technologies to buildings in Christchurch, by interviewing the structural engineers responsible for the design of six case study structures. Focus is given to the structural performance and benefits of each technology, and the key factors driving the clients' and engineers' decision to use the system. Comparisons are then made between resilient technologies, looking at the relative construction times and cost, areas of difficulty in design and construction, and the expected performance. Assessments are made of the knowledgeability of stakeholders, including clients and engineers, in resilient design, and the aspects that need to be addressed in the ongoing research and development of new and existing resilient technologies. Results show that the main factors identified driving clients' and engineers' decisions to use a seismic-resilient design were the structural performance, ease of construction and publicity. Key issues that need to be addressed during the development of new resilient systems are the durability, constructability and cost of a design, in addition to the production of design and construction aids, to both support engineers and contractors in the process, and encourage them to undertake a seismic-resilient design. Ideas are presented for increasing client and public awareness of different resilient systems available so that the demand and commission for seismic-resilient buildings in the city may increase. [ABSTRACT FROM AUTHOR]

Homeless library customers often face barriers to equitable library use. This study examined homeless library customers' perspectives on general and targeted public library services, and social inclusion. Findings presented in the paper come from a qualitative phenomenological study comprising semi-structured in-depth interviews with seven self-identified regular library users of a public library in Christchurch, New Zealand, who were experiencing homelessness at the time of the study. Findings report on a diverse range of information needs and motivations for visiting a public library. Participants viewed the public library as a safe, warm, and quiet place in which to relax and escape difficulties related to experiencing homelessness. The results reflect changes in the role of public libraries and in the expectations of customers, and discuss a need for targeted library services in the form of specialist gatekeeper roles such as that of a community liaison. This study evaluated the effectiveness of general and targeted library services from users' points of view, providing insights which could be used to inform the design of relevant information policies and services. [ABSTRACT FROM AUTHOR]

The Canterbury Earthquake Sequence (CES), which includes the 2010 and 2011 Christchurch earthquakes, is one of the deadliest disasters in New Zealand history. Following the CES, displacement of the affected population occurred, leading to an out‐migration from affected areas and changes to places of residence. This paper investigates the spatial changes in population following the CES, using a multiscale geographically weighted regression (MGWR) analysis approach to examine if there is a relationship between population change within the Canterbury region, and potential driving forces across two time periods: 2006–2013 and 2013–2018. The findings of this study could assist in informing future decision making and planning for earthquake events and to increase the effectiveness of land use policy decisions for post‐disaster recovery in New Zealand. [ABSTRACT FROM AUTHOR]

This paper takes as its starting point Aotearoa New Zealand Prime Minster Jacinda Ardern's stated politics of kindess. From her response to the 2019 Christchurch mosque attacks to her communicative approach to Covid 19, this rhetoric has been central to Ardern's government's political identity. Such an emphasis on kindness allows us to consider how the affectivities associated with it are deployed as a basis for the instrumentalization of care, and this article examines the relationship between a politics of kindness and the practices of care. From a performance point of view, I examine the distinctions between policies of kindness as either happily (felicitous) performative a practice of meaningful transformation or unhappily performative in the sense meant by Sara Ahmed when she describes the unhappy performativity of statements of anti-racism that fail to enact what they declare (2004). To work through such distinctions, I consider examples of performances of care in Aotearoa that span protest and performance practice. Through these examples, I ask how policies of care might become truly caring in practice and consider how the domains of government, civil society and artistic practice might inform one another in this endeavour. Aotearoa's orientation towards an often-fraught politics of kindness provides an opportunity to reflect on not just the necessary scrutiny of such political language, but also on the openings it provides to think about the performativity of what Donna Haraway calls kin-making in the 21st century. [ABSTRACT FROM AUTHOR]

Nowadays, investigating the effectiveness of high modulus columns in liquefaction mitigation is one of the important tasks in earthquake geotechnical engineering. Although there is limited data from the field and laboratory to verify the performance of high modulus columns (HMCs), available case histories, physical model tests, and reliable numerical methods provide important information in order to analyze the role of HMCs in liquefaction mitigation. In this paper, the seismic performance of a liquefied site improved with rammed aggregate piers (RAPs) is investigated through the results of a full-scale field test. Results of cone penetration test (CPT) and cross-hole shear wave velocity ( V s ) test before and after RAP treatment at the test site are assessed to achieve properties of the natural (unimproved) soil, RAP, and the surrounding (improved) soil. The effectiveness of RAPs in liquefaction mitigation is evaluated in terms of pre-and post-improvement factor of safeties against liquefaction, liquefaction-induced deformations, and ground failure indices, which are calculated using shear strain compatibility and incompatibility approaches. The research results showed that RAPs exhibit a satisfying performance when computations are made considering shear strain compatibility in the computation of seismic shear stress reduction factor. On the contrary, the effectiveness of RAPs during the shear strain incompatibility approach is significantly smaller than the ones computed from the current design method based on shear strain compatibility approach. The findings of this study provide a basis for the performance-based ground improvement design through HMCs to mitigate soil liquefaction and also extend knowledge about HMC-improved seismic soil response by presenting the results of liquefaction vulnerability parameters before and after soil improvement of a field test study. [ABSTRACT FROM AUTHOR]

This paper examines the discursive construction of Prime Minister Jacinda Ardern after she wore a veil following the unprecedented terror attack in two mosques in the city of Christchurch in 2019. The articles analyzed are collected from three main newspapers published in New Zealand's three main cities. Analyzed using principles and tools from Critical Discourse Studies (CDS) and Argumentum Model of Topics (AMT) more specifically, the articles reveal key arguments from both sides i.e. in support of and against this unparalleled initiative on behalf of a political leader in the western world. On the one hand, the majority of the news articles under analysis portray PM's initiative as one that attempts to mitigate tension and conflict while bringing solidarity to a grief-stricken nation; and thus, are based on the 'locus from ontological implications'. While the perspectives that oppose the initiative vary from explicit racist ones that present Muslims as threat to Zealand, to those who strongly believe such actions support the women oppression. Through a (de-)construction of the arguments opposing this move, the findings demonstrate that the opposition towards PM's initiative is based on two main loci namely the 'locus from correlates' and the 'locus from termination and setting up' [ABSTRACT FROM AUTHOR]

Recovery of damaged water supply systems after severe earthquakes is one of the priorities to return to normal conditions. Water supply systems are intrinsically interdependent with other important lifelines such as transportation, energy, health care, and industrial sectors. These interdependencies need to be better understood by means of empirical data and analytical models. This paper is primarily of archival nature and describes empirical impact data of large earthquakes in Chile (Maule 2010), New Zealand (Christchurch 2010–2011), and Japan (Tohoku 2011) on their respective drinking water systems, and summarizes damage observations, emergency actions, and restoration processes within a resilience framework focused on metrics of robustness and rapidity. The archival nature of this article is justified by the paramount importance of systematic data collection to improve network resilience for future analytical models that aim to predict the response and recovery of water networks. Moreover, based on the collected data, the effectiveness of response actions and implemented countermeasures are evaluated relative to the observed earthquake performance of the system components. Important observations are derived to understand the main factors causing water supply system outages, the effectiveness of strategies used, and their capacity to restore the service. [ABSTRACT FROM AUTHOR]

The effects of strong ground shaking on hillslope stability can persist for many years after a large earthquake, leading to an increase in the rates of post earthquake land sliding. The factors that control the rate of post‐earthquake land sliding are poorly constrained, hindering our ability to reliably forecast how landscapes and landslide hazards and risk evolve. To address this, we use a unique data set comprising high‐resolution terrestrial laser scans and airborne lidar captured during and after the 2010–2011 Canterbury Earthquake Sequence, New Zealand. This earthquake sequence triggered thousands of rock falls, and rock and debris avalanches (collectively referred to as "rockfall"), resulting in loss‐of‐life and damage to residential dwellings, commercial buildings and other infrastructure in the Port Hills of Christchurch, New Zealand. This unique data set spans 5 years and includes five significant earthquakes. We used these data to (a) quantify the regional‐scale "rockfall" rates in response to these earthquakes and the postearthquake decay in rockfall rates with time; and (b) investigate the site‐specific factors controlling the location of seismic and nonseismic rockfalls using frequency ratios and logistic regression techniques. We found that rockfall rates increased significantly in response to the initial earthquake that generated the strongest shaking in the sequence—The MW 6.2 22 February 2011 event—Compared to the long‐term background rates derived from the dating of pre‐2010 talus piles at the toe of the slopes. Non seismic rockfall rates also increased immediately after the 22 February 2011 earthquake and decayed with time following a power‐law trend. About 50% of the decay back to the pre‐earthquake rockfall rates occurred within 1–5 years after the 22 February 2011 earthquake. Our results show that the short‐term decay in rockfall rates over time, after the initial earthquake, was attributed to the subsequent erosion of seismically damaged rock mass materials caused by environmental processes such as rain. For earthquake‐induced rockfall at the regional‐scale, the peak ground accelerations is the most significant variable in forecasting rockfall volume, followed by the relative height above the base of the slope. For both earthquake and non‐seismic conditions at the site‐specific scale, the probability of rockfall increases when the adjacent areas have failed previously, indicating that accrued damage preconditions localized areas of the slope for subsequent failure. Such preconditioning is a crucial factor driving subsequent rockfalls; that is, future rockfalls are likely to cluster near areas that failed in the past. Plain Language Summary: Evidence from previous earthquakes suggests that the frequency of land sliding after a large earthquake is significantly higher than before it. Strong earthquakes cause slope cracking and generate landslide debris, which can be more readily remobilized post earthquake, creating new hazards, including further landslides and landslide dams. These hazards may persist for years and decades and represent a prolonged risk that the impacted communities must consider. Currently, the relative increase in land sliding and rate of decay during and after a major earthquake is rarely quantified, thus posing a knowledge gap for those rebuilding after a major earthquake. This paper explores high‐resolution terrestrial laser scan models of slope surfaces and how these surfaces changed during and after strong earthquake shaking during the 2010–2011 Canterbury Earthquake Sequence (CES) in New Zealand. These surface "change" models were used to quantify the volumes of debris–rock and soil–that fell from these slopes during and after the CES. These data were used to establish a regional‐scale, physical relationship between the volume of debris falling from the cliffs per earthquake or unit of time, per unit area of slope. Using the change models, we investigated the factors that control the temporal and spatial distribution of the rockfalls at the regional‐ and site‐specific scales. At the regional scale, we found that the size of the slope and the relative increase in rockfall rates above pre‐CES rates controlled the subsequent non‐seismic rockfall decay time. At the site‐specific scale, the main conclusions from this study are: (a) for earthquake triggers, the peak ground acceleration (a measure of earthquake ground shaking) was the most important variable in forecasting the probability of failure, followed by the relative elevation or height above the base of the slope; and (b) for both earthquake and nonseismic triggers, the probability of failure increases when the adjacent areas have failed previously, indicating that preconditioning of the slope to failure is a key factor driving subsequent rockfalls. Key Points: We quantify rock slope changes during and after a major earthquake sequence through repeat high‐resolution terrestrial laser scan surveysWe analyze landslide rates over 5 years, during and after the earthquakes at the regional‐ and site‐specific scalesNon seismic landslide rates are heightened immediately after the initial earthquake and decayed with time (1–5 years) following a power‐law trend [ABSTRACT FROM AUTHOR]

Globally, electric scooters (e-scooters) have grown in popularity in recent years. Introducing new transport modes is complex because existing infrastructures and habits do not easily accommodate them, which can lead to conflict between different types of transport users. In this paper, we explore e-scooter riders' and pedestrians' experiences of sharing space in Christchurch, New Zealand. In-depth interviews were carried out with e-scooter riders and pedestrians in 2019. Thematic analysis of the data highlighted the uneven and unfamiliar socio-spatial encounters between e-scooter riders and pedestrians. We explore the ways that e-scooter riders' and pedestrians' rhythms, in interaction with the sensory, affectual and material, create blurry boundaries. These blurry boundaries are evident in the ways that e-scooter riders blur modal status, sensory experiences and the regulations of different transport spaces. It is important to understand e-scooter riders' and pedestrians' experiences and interpretations of boundaries in order to plan transport spaces that support active and low-carbon modes of transport. [ABSTRACT FROM AUTHOR]

This paper critically explores possibilities for feminist solidarities and empathic identification in digital atmospheres. It is written in response to disparate experiences of solidarity and appropriation shared via feminist hashtags that trended following the terror attack on Muslim communities in Ōtautahi, Christchurch in March 2019. It considers two cases of hashtag feminism shared by prominent female politicians in the aftermath of the attack: 1) the #TheyAreUs hashtag shared by Prime Minister Jacinda Ardern; and 2) the #TheyAreUsShutdown hashtag shared by Green Party Member Golriz Ghahraman. My research combines a network analysis and Critical Technocultural Discourse Analysis to assess the connective and discursive power of hashtags. Adopting a critical feminist ethic of empathy , I interrogate the influence of female politicians and their role in galvanising solidarity across international and intersectional feminisms to produce politically effective outcomes. I argue that the affecting power of empathy is heightened by the networked affordances of hashtags which have the potential to either fracture or transverse boundaries across feminisms. [ABSTRACT FROM AUTHOR]

A geospatial data processing tool, GEO4PALM, has been developed to generate geospatial static input for the Parallelised Large Eddy Simulation (PALM) model system. PALM is a community-driven large eddy simulation model used for atmospheric and environmental research. Throughout PALM's 20-year development, research interests have been increasing in its application in realistic conditions, especially for urban areas. For such applications, geospatial static input is essential. Although abundant geospatial data are accessible worldwide, currently, no tools are available in the community to automatically generate PALM's geospatial static input for most areas of the world. In addition, geospatial data availability and quality are highly variable and inconsistent. Therefore, PALM users face significant challenges, particularly regarding data acquisition, data pre-processing, and conversion of all information and metadata into PALM Input Data Standard (PIDS). This paper presents and describes a free and open-source tool, GEO4PALM, to help users generate the PALM static input with a simple and standardized process. GEO4PALM is compatible with geospatial data obtained from any source provided that the data sets comply with common geo-information formats. Users can either provide existing geospatial data sets or use the embedded data interfaces to download geo-information data from free online sources for any global geographic area of interest. All online data sets incorporated in GEO4PALM are globally available with several data sets having the finest resolution of 1 m. Two application examples are presented to demonstrate successful PALM simulations driven by geospatial input generated by GEO4PALM using different geospatial data sources for Berlin, Germany and Christchurch, New Zealand. GEO4PALM provides an easy and efficient way for PALM users to configure and conduct PALM simulations for applications and investigations such as urban heat island effects, air pollution dispersion, renewable energy resourcing, and weather-related hazard forecasting. [ABSTRACT FROM AUTHOR]

The Canterbury Earthquake Sequence (CES) adversely impacted built, economic and social environments. This included widespread physical damage to the water supply pipe network in Christchurch, resulting in long service disruptions. The transient and permanent ground deformations generated by the earthquakes in the CES caused a range of pipe damage, particularly in the MW 6.2 22 February 2011 and the relatively less damaging MW 6.0 13 June 2011 event. Damage to the pipes in both events was largely attributed to liquefaction and lateral spreading effects. Pipes made of ductile material (e.g. PVC, HDPE) sustained lesser damage (and therefore lower repair rates) compared to the pipes made of non-ductile material (e.g. AC, CI). In all cases, the repair rates (number of repairs per kilometre) typically increased with increasing liquefaction severity. Utilising the pipe repair dataset and Liquefaction Severity Number (LSN) maps generated from extensive geotechnical investigation following the CES events, new repair rate prediction models for water pipes subjected to liquefaction effects have been derived and are presented in this paper. Repair data from both earthquakes has been analysed independently and in combination, providing two sets of repair rate functions and different levels of uncertainty. Repair rate functions were first derived from pipes grouped by combination of diameter (i.e. ϕ < 75 mm or ϕ = 75 mm) and material type (i.e. ductile or non-ductile). The models were then refined by adding correction factors for those material types and diameters with sufficient sample length. Correction factors were derived for AC, CI, PVC pipes of diameter =75 mm and for MDPE and HDPE80 pipes of diameter <75 mm. Galvanised Iron (GI) pipes performed poorly during the earthquakes, resulting in very high repair rates compared to the other non-ductile pipes of diameter <75 mm damaged in the network; this warranted a separate repair rate model to be developed for this pipe type. The proposed models can be used in risk assessment of water pipe networks; i.e. to estimate the number of pipe repairs from potential liquefaction damage from future earthquakes. [ABSTRACT FROM AUTHOR]

This paper presents a new framework for the seismic loss prediction of residential buildings in Christchurch, New Zealand. It employs data science techniques, geospatial tools, and machine learning (ML) trained on insurance claims data from the Earthquake Commission (EQC) collected following the 2010-2011 Canterbury Earthquake Sequence (CES). The seismic loss prediction obtained from the ML model is shown to outperform the output from existing risk analysis tools for New Zealand for each of the main earthquakes of the CES. In addition to the prediction capabilities, the ML model delivered useful insights into the most important features contributing to losses during the CES. ML correctly highlighted that liquefaction significantly influenced buildings losses for the 22 February 2011 earthquake. The results are consistent with observations, engineering knowledge, and previous studies, confirming the potential of data science and ML in the analysis of insurance claims data and the development of seismic loss prediction models using empirical loss data. [ABSTRACT FROM AUTHOR]

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is an airborne observatory for far-infrared astronomy stationed at the Armstrong Flight Research Center (AFRC) in Palmdale, CA, USA. Although SOFIA flies at altitudes of ∼41,000 ft, any far-infrared observations from within the Earth’s atmosphere are nevertheless hampered by water vapor absorbing the astronomical signal. The primary atmospheric parameter governing absorption in the far-infrared is the total upward precipitable water vapor, PWV. In this paper we present global PWV maps derived from re-analyses from the European Centre for Medium-Range Weather Forecasts, ECMWF, with a geographical resolution of 0.°5, for flight altitudes ranging from 37,000 ft to 45,000 ft and each meteorological season. These maps were validated with FIFI-LS PWV measurements on board SOFIA and allow an investigation of the global morphology and seasonal dependence of the total upward PWV in the stratosphere. We additionally investigate the observing conditions, in terms of PWV, at various locations, especially around SOFIA’s home base, Palmdale, but also around sites in the southern hemisphere like Tahiti, Santiago de Chile (Chile), Buenos Aires (Argentina), and Christchurch (New Zealand). From the southern sites investigated Christchurch provides the best conditions in terms of PWV (and efficiency), Tahiti the worst. Using total power sky measurements with FIFI-LS we also derive a mean emissivity of the telescope (primary, secondary and tertiary mirror) of ϵ Tel = 20.5 ± 1.6% around the astronomically significant [C ii ] emission line. We finally compare atmospheric re-analyses from GEOS (MERRA-2) and ECMWF (ERA5) to our FIFI-LS PWV measurements. Both re-analyses correlate linearly with our FIFI-LS PWV measurements from all flight altitudes but with different scaling factors. However, MERRA-2 correlates significantly less well than ERA5 especially for flight altitudes below 41,000 ft. [ABSTRACT FROM AUTHOR]

There has been extensive research in traffic state estimation that accounts for the stochastic nature of traffic flow models. However, these studies often exhibit limitations such as an exclusive focus on motorway traffic and a reliance on a single data source. This paper departs from these methods by introducing a stochastic estimation framework that is specifically designed for urban arterial traffic. The framework has the capability to incorporate multiple data sources, which serves to improve its accuracy and robustness. The framework is composed of three components: (i) a stochastic traffic flow model, (ii) a filtering algorithm, and (iii) an algorithm for incorporating multi-source measurements. In terms of the traffic model, we introduce a new stochastic Switching Mode Model that can be applied to arterial roads that have both signalized and unsignalized intersections. This model does not consider uncertainty in the current mode of operation, which substantially reduces the computational complexity because there is only one mode at each time step. Furthermore, we propose three different filtering algorithms for multi-source traffic estimation, including the incremental stochastic Kalman Filter (SKF), the incremental stochastic Unscented Kalman Filter (SUKF), and the hybrid approach. Since the SKF can only deal with linear functions, non-linear measurement equations need to be linearized using first-order Taylor expansions. The SUKF is based on the Unscented Transform (UT), which enables it to work with a wider range of functions regardless of linearity, non-linearity, or non-differentiability. The hybrid algorithm is a combination of the SKF and the SUKF, in which linear equations are treated similarly to the SKF, and non-linear equations are handled with the UT in the same way as in the SUKF. The performances of these algorithms were similar when applied to the synthetic data of an urban arterial in Christchurch CBD, New Zealand. The hybrid algorithm, however, worked slightly better and was more stable than the other two. • Extended Switching Mode Model for signalized/unsignalized corridors. • Efficient approach excludes mode uncertainty but retains stochastic model parameters. • Three filtering algorithms for traffic estimation using multiple data sources. [ABSTRACT FROM AUTHOR]

Genetic variants in the apolipoprotein E (APOE) gene affect the onset and progression of Alzheimer’s disease (AD). The APOE Christchurch (APOE Ch) variant has been identified as the most prominent candidate for preventing the onset and progression of AD. In this study, we generated isogenic APOE3Ch/3Ch human-induced pluripotent stem cells (iPSCs) from APOE3/3 healthy control female iPSCs and induced them into astrocytes. RNA expression analysis revealed the inherent resilience of APOE3Ch/3Ch astrocytes to induce a reactive state in response to inflammatory cytokines. Moreover, cytokine treatment changed astrocytic morphology with more complexity in APOE3/3 astrocytes, but not in APOE3Ch/3Ch astrocytes, indicating resilience of the rare variant to a reactive state. Interestingly, we observed robust morphological alterations containing more intricate processes when cocultured with iPSC-derived cortical neurons, in which APOE3Ch/3Ch astrocytes reduced complexity compared with APOE3/3 astrocytes. To assess the impacts of tau propagation effects, we next developed a sophisticated and sensitive assay utilizing cortical neurons derived from human iPSCs, previously generated from donors of both sexes. We showed that APOE3Ch/3Ch astrocytes effectively mitigated tau propagation within iPSC-derived neurons. This study provides important experimental evidence of the characteristic functions exhibited by APOE3Ch/3Ch astrocytes, thereby offering valuable insights for the advancement of novel clinical interventions in AD research. [ABSTRACT FROM AUTHOR]

Ascidians are marine filter-feeder chordates. Botrylloides ascidians possess diverse biological properties such as whole-body regeneration (WBR), hibernation/aestivation, blastogenesis, metamorphosis, and natural chimerism. However, the absence of distinctive morphological features often makes identification difficult. Botrylloides diegensis is an ascidian that has been misidentified in previous studies and is recorded in GenBank as Botrylloides leachii owing to the high morphological similarity between the sister species. More available sequences and strategies for identification would help resolve some of the confusion surrounding its ambiguous nature. We collected several Botrylloides samples from seven locations in Aotearoa New Zealand (Dunedin, Christchurch, Picton, Nelson, Whangateau, New Plymouth, and Invercargill) and barcoded the species based on Cytochrome Oxidase I, Histone 3, 18S, and 28S ribosomal RNA markers. Network and Bayesian trees confirmed the presence of three Botrylloides species: B. diegensis, Botrylloides jacksonianum, and Botrylloides affinis anceps. [ABSTRACT FROM AUTHOR]

Background: Due to the remarkable growth in online retail sales in New Zealand, a large number of parcels are needed to be delivered to consumers' doorsteps. Home deliveries in major New Zealand cities (e.g., Christchurch) typically occur between 9 a.m. and 6 p.m. on weekdays, when many home delivery attempts fail. This leads to adverse effects, such as vehicular traffic in residential areas and greater air pollution per parcel delivered. However, home deliveries outside of typical business hours (i.e., before 9 a.m. and after 5 p.m.) might be worthwhile to help subside the above issues. Therefore, this study investigated consumers' preferences for receiving home deliveries during various times, such as early morning, morning, afternoon, late afternoon, and evening. Methods: The data used in this study were obtained via an online survey of 355 residents of Christchurch city. Non-parametric tests, namely the Friedman test, Wilcoxon signed-rank test, and ordinal logistic regression, were carried out to examine consumer preferences for the above time slots. Results: The results showed that consumers preferred the late afternoon (3 p.m. to 6 p.m.) time slot the most for receiving home deliveries. Conclusion: It appeared that the off-peak delivery option is less likely to draw the desired consumer patronage and is thus less likely to assist in lowering the number of unsuccessful home deliveries, the transportation costs incurred by service providers, traffic congestion, and pollution in urban areas. [ABSTRACT FROM AUTHOR]

The effect of spatial variability on the liquefaction prediction and liquefaction-induced ground failure of a soil profile with thinly interbedded layer of sand and clay was examined using simplified procedures and fully coupled two-dimensional (2D) nonlinear dynamic analysis (NDA). The Palinurus Road site in Christchurch, New Zealand, subjected to the 2010 Darfield and 2011 Christchurch events, was selected for the analyses. The liquefaction vulnerability of the site was estimated using one-dimensional (1D) liquefaction vulnerability indices (LVIs), and the results were compared with the results of NDAs and field observations. Spatially correlated random fields conditioned on corrected cone penetration tests (CPTs) were generated based on sand-like and claylike portions of the interbedded soil profile. CPT data were corrected for the thin-layer and transition zone effects. The generated random fields were assigned to the interbedded layer of the stochastic model to examine the effect of spatial variability on the system dynamic response, cross-interaction between layers, and liquefaction-induced diffusion during the evolution of liquefaction and postliquefaction. The potential of sediment ejecta manifestation using the artesian flow potential (AFP) and ejecta potential index (EPI) also was investigated for the stochastic models and compared with those of deterministic models. This study demonstrates the value of advanced 2D NDA modeling with realistic soil spatial variability for understanding inconsistent ejecta predictions from simplified tools. The approach can guide future refinements to assessment procedures and provide insights into key factors controlling manifestation in complex stratified sites. [ABSTRACT FROM AUTHOR]

In this paper, we investigate how infrastructure and care shape commoner subjectivities. In our research into an urban youth farm in Aotearoa New Zealand, we heard and observed profound tales of growth and transformation among youth participants. Not only were our interviewees narrating stories of individual transformation (of themselves and others), but they also spoke of transformations in the way they engaged with the world around them, including the land and garden and its many species and ecological systems, the food system more generally, the wider community and their co-workers. Such transformations were both individual and collective, having more in common with the collective caring subject homines curans than the autonomous, rational work-ready subject of homo economicus. Using postcapitalist theory on commons, commoning and subjectivity, we argue that these socio-affective encounters with more-than-human commons enabled collective, caring commoner subjectivities to emerge and to be cultivated through collective care in place. We suggest that the commons can be thought of as an infrastructure of care for the counter-city, providing the conditions for the emergence and cultivation of collective caring urban subjects. • A postcapitalist counter-city in post-earthquake Christchurch challenges capitalist city discourses. • Collective work on an urban youth farm fosters caring subjectivities and challenges individualist subjectivities. • An urban farm can nurture a more-than-human community, transforming vacant space into a commons. • Urban commons can be infrastructures of care for the counter-city, fostering postcapitalist subjectivities and futures. [ABSTRACT FROM AUTHOR]

The concept of seismically low-damage structures was introduced by researchers to decrease the likelihood of irreparable damage as well improving the response of the structure. The need to shift from conventional ductile design to a less ductility (damage) oriented design was emphasised by different researchers in New Zealand and across the world back in the 1990s and 2000s. Damage Avoidance Design (DAD) philosophy introduced in the early 2000s took the idea of low-damage design to another level. Self-centring is the main aspect of a DAD designed. However, the need to change the seismic design philosophy was mostly felt by the community and decisions makers after the considerable financial and social loss resulted from the 2011 Christchurch earthquake. Several damage-avoidance concepts and solutions have been introduced and developed in the past. However, most of these solutions haven't been widely implemented in practice because of the complexity and extra construction costs. This research aims to overcome this gap by introducing a new solution that can be easily adopted by the construction industry without imposing extra complexity and construction costs. This paper presents the development of a new innovative seismic device named as Self-Centring Structural Connector (SSC) as a new self-centring friction damping device. The main purpose of this device is to provide a cost-efficient yet flexible solution to achieve a range of efficient DAD structures in practice. In this paper, the principles of the force-deflection relationship for the SSC is analytically developed and validated through experimental investigation. In addition, the influence of various parameters affecting joint performance are studied through an analytical model. Finally, some possible applications of this device are introduced. As per the findings based on the analytical modelling and experimental investigation, it can be observed that the joint performs well to achieve the design and construction objectives making it a suitable solution for DAD. [ABSTRACT FROM AUTHOR]

Coupled surface–atmosphere high-resolution mesoscale simulations were carried out to understand meteorological processes involved in the radiation fog life cycle in a city surrounded by complex terrain. The controls of mesoscale meteorology and microscale soil moisture heterogeneity on fog were investigated using case studies for the city of Ōtautahi / Christchurch, New Zealand. Numerical model simulations from the synoptic to microscale were carried out using the Weather Research and Forecasting (WRF) model and the Parallelised Large-Eddy Simulation Model (PALM). Heterogeneous soil moisture, land use, and topography were included. The spatial heterogeneity of soil moisture was derived using Landsat 8 satellite imagery and ground-based meteorological observations. Nine semi-idealised simulations were carried out under identical meteorological conditions. One contained homogeneous soil moisture of about 0.31 m3m-3 , with two other simulations of halved and doubled soil moisture to demonstrate the range of soil moisture impact. Another contained heterogeneous soil moisture derived from Landsat 8 imagery. For the other five simulations, the soil moisture heterogeneity magnitudes were amplified following the observed spatial distribution to aid our understanding of the impact of soil moisture heterogeneity. Analysis using pseudo-process diagrams and accumulated latent heat flux shows significant spatial heterogeneity of processes involved in the simulated fog. Our results showed that soil moisture heterogeneity did not significantly change the general spatial structure of near-surface fog occurrence, even when the heterogeneity signal was amplified and/or when the soil moisture was halved and doubled. However, compared to homogeneous soil moisture, spatial heterogeneity in soil moisture can lead to changes in fog duration. These changes can be more than 50 min , although they are not directly correlated with spatial variations in soil moisture. The simulations showed that the mesoscale (10 to 200 km) meteorology controls the location of fog occurrence, while soil moisture heterogeneity alters fog duration at the microscale on the order of 100 m to 1 km. Our results highlight the importance of including soil moisture heterogeneity for accurate spatiotemporal fog forecasting. [ABSTRACT FROM AUTHOR]

The actual lateral wheel path distribution (LWD) on roads differs from the design assumptions. This leads to premature deterioration of chip-sealed pavements in the form of flushing and ravelling resulting in subsequent maintenance costs. The location of LWD is key to calibrating the variable-rate bitumen spray bar used to minimise flushing and ravelling during chip seal construction. Current methods used to estimate the location of LWD rely on visual inspection. This is subjective and reliant on individual expertise. This study aims to automate obtaining LWD by developing an Internet of Things (IoT) prototype to locate the LWDs. This prototype was tested by collecting LWDs from 22 locations in Christchurch, New Zealand. Results show that narrow roads exhibit a concentrated wheel path distribution. Specifically, increasing single lane carriageway width leads to a significant rise in the standard deviation (spread) and position of the LWDs among 22 locations investigated. Cycle lanes or parking bays significantly influence the location and distribution of LWD. There is no clear link between road camber and LWD. The findings can be used to improve the calibration of the variable-rate bitumen spray bar and inform pavement and traffic engineers to enhance construction and maintenance practices.. [ABSTRACT FROM AUTHOR]

This study introduces a generalisation of the classical one-dimensional liquefaction severity indexes to extend their predictive capability for the occurrence of lateral spreading. After a critical overview of the most used indexes, the rationale for extension to bi-dimensional conditions determined by non-horizontal geomorphology is presented, together with the rule to achieve generalisation. The efficacy of the new index is demonstrated with a performance-based study on two cases, the earthquakes of 20 May 2012 (Mw 6·1) at Terre del Reno (Emilia-Romagna, Italy) and 11 February 2011 (Mw = 6·2) at Christchurch (New Zealand). Stratigraphic attributes including thickness, depth, composition and relative density of the liquefiable layers, obtained over the whole territories from rich datasets of cone penetration tests, are coupled with topographic information derived from the digital elevation model to provide the input for the analysis. Consistency assessment and spatial interpolation of data are carried out with geostatistical tools implemented in a geographic information system platform. Validation against a post-earthquake damage survey, quantified with a binary classification method, shows the paramount role of the bi-dimensional conditions. [ABSTRACT FROM AUTHOR]

Soil liquefaction often occurs as a secondary hazard during earthquakes and can lead to significant structural and infrastructure damage. Liquefaction is most often documented through field reconnaissance and recorded as point locations. Complete liquefaction inventories across the impacted area are rare but valuable for developing empirical liquefaction prediction models. Remote sensing analysis can be used to rapidly produce the full spatial extent of liquefaction ejecta after an event to inform and supplement field investigations. Visually labeling liquefaction ejecta from remotely sensed imagery is time-consuming and prone to human error and inconsistency. This study uses a partially labeled liquefaction inventory created from visual annotations by experts and proposes a pixel-based approach to detecting unlabeled liquefaction using advanced machine learning and image processing techniques, and to generating an augmented inventory of liquefaction ejecta with high spatial completeness. The proposed methodology is applied to aerial imagery taken from the 2011 Christchurch earthquake and considers the available partial liquefaction labels as high-certainty liquefaction features. This study consists of two specific comparative analyses. (1) To tackle the limited availability of labeled data and their spatial incompleteness, a semi-supervised self-training classification via Linear Discriminant Analysis is presented, and the performance of the semi-supervised learning approach is compared with supervised learning classification. (2) A post-event aerial image with RGB (red-green-blue) channels is used to extract color transformation bands, statistical indices, texture components, and dimensionality reduction outputs, and performances of the classification model with different combinations of selected features from these four groups are compared. Building footprints are also used as the only non-imagery geospatial information to improve classification accuracy by masking out building roofs from the classification process. To prepare the multi-class labeled data, regions of interest (ROIs) were drawn to collect samples of seven land cover and land use classes. The labeled samples of liquefaction were also clustered into two groups (dark and light) using the Fuzzy C-Means clustering algorithm to split the liquefaction pixels into two classes. A comparison of the generated maps with fully and manually labeled liquefaction data showed that the proposed semi-supervised method performs best when selected high-ranked features of the two groups of statistical indices (gradient weight and sum of the band squares) and dimensionality reduction outputs (first and second principal components) are used. It also outperforms supervised learning and can better augment the liquefaction labels across the image in terms of spatial completeness. [ABSTRACT FROM AUTHOR]