The 2011 Great East Japan Tsunami exposed many hidden weaknesses in Japan's tsunami countermeasures. Since then, many improvements have been made in both structural measures (numerical simulations, ...coastal defense structures, building damage assessment and control forests) and nonstructural measures (warning/observation and evacuation). This review summarizes the lessons and improvements in the five-year time period after the 2011 event. After five years, most of the lessons from the 2011 tsunami have been applied, including more realistic tsunami simulations using very fine grids, methods to strengthen coastal defense structures, building evacuations and coastal forests, improved warning content and key points to improve evacuation measures. Nevertheless, large future challenges remain, such as an advanced simulation technique and system for real-time hazard and risk prediction, implementation of coastal defense structures/multilayer countermeasures and encouraging evacuation. In addition, among papers presented at the coastal engineering conference in Japan, the proportion of tsunami-related research in Japan increased from 15% to 35% because of the 2011 tsunami, and approximately 65-70% of tsunami-related studies involve numerical simulation, coastal structures and building damage. These results show the impact of the 2011 tsunami on coastal engineering related to academic institutions and consulting industries in Japan as well as the interest in each tsunami countermeasure.
Speculative execution, the base on which modern high-performance general-purpose CPUs are built on, has recently been shown to enable a slew of security attacks. All these attacks are centered around ...a common set of behaviors: During speculative execution, the architectural state of the system is kept unmodified, until the speculation can be verified. In the event that a misspeculation occurs, then anything that can affect the architectural state is reverted (squashed) and re-executed correctly. However, the same is not true for the microarchitectural state. Normally invisible to the user, changes to the microarchitectural state can be observed through various side-channels, with timing differences caused by the memory hierarchy being one of the most common and easy to exploit. The speculative side-channels can then be exploited to perform attacks that can bypass software and hardware checks in order to leak information. These attacks, out of which the most infamous are perhaps Spectre and Meltdown, have led to a frantic search for solutions.
In this work, we present our own solution for reducing the microarchitectural state-changes caused by speculative execution in the memory hierarchy. It is based on the observation that if we only allow accesses that hit in the L1 data cache to proceed, then we can easily hide any microarchitectural changes until after the speculation has been verified. At the same time, we propose to prevent stalls by value predicting the loads that miss in the L1. Value prediction, though speculative, constitutes an invisible form of speculation, not seen outside the core. We evaluate our solution and show that we can prevent observable microarchitectural changes in the memory hierarchy while keeping the performance and energy costs at 11% and 7%, respectively. In comparison, the current state of the art solution, InvisiSpec, incurs a 46% performance loss and a 51% energy increase.
In this paper, we address the problem of target detection in the presence of coherent (or fully correlated) signals, which can be due to multipath propagation effects or electronic attacks by smart ...jammers. To this end, we formulate the problem at hand as a multiple-hypothesis test that, besides the conventional radar alternative hypothesis, contains additional hypotheses accounting for the presence of an unknown number of interfering signals. In this context and leveraging the classification capabilities of the Model Order Selection rules, we devise penalized likelihood-ratio-based detection architectures that can establish, as a byproduct, which hypothesis is in force. Moreover, we propose a suboptimum procedure to estimate the angles of arrival of multiple coherent signals ensuring (at least for the considered parameters) almost the same performance as the exhaustive search. Finally, the performance assessment, conducted over simulated data and in comparison with conventional radar detectors, highlights that the proposed architectures can provide satisfactory performance in terms of probability of detection and correct classification.
Due to the rapid development of information technology, traditional classroom teaching is not able to meet the needs of students. Therefore, colleges and universities are paying more and more ...attention to cultivating students’ individuality and comprehensive quality. The “student-centered, teacher-led” online and offline hybrid teaching mode emerged as the times require, and has become a new teaching method, which has gradually become the focus of attention of colleges and universities. In the teaching practices of colleges and universities, blended instruction has made some progress, but issues with instruction quality also arise. Upon review of the relevant literature and interviews with teachers and students, this study determined that outmoded teaching practices, lack of awareness of students’ independent learning, and absence of external conditions in colleges and universities are the most influential factors affecting the quality of mixed teaching. Based on these, corresponding measures are proposed from the perspectives of teachers, students, and schools to aid the development of blended teaching in colleges and universities and improve its effects. Teachers should continuously improve their hybrid teaching skills and ensure quality. Moreover, students should improve their sense of participation in teaching activities and develop a consciousness of independent learning. Finally, the school should improve the support structure to implement blended teaching seamlessly.
This study is the first to scrutinize the psychological effects of online astroturfing in the context of Russia’s digitally enabled foreign propaganda. Online astroturfing is a communicative strategy ...that uses websites, “sock puppets,” or social bots to create the false impression that a particular opinion has widespread public support. We exposed N = 2353 subjects to pro-Russian astroturfing comments and tested: (1) their effects on political opinions and opinion certainty and (2) the efficiency of three inoculation strategies to prevent these effects. All effects were investigated across three issues and from a short- and long-term perspective. Results show that astroturfing comments can indeed alter recipients’ opinions, and increase uncertainty, even when subjects are inoculated before exposure. We found exclusively short-term effects of only one inoculation strategy (refutational-same). As these findings imply, preemptive media literacy campaigns should deploy (1) continuous rather than one-time efforts and (2) issue specific rather than abstract inoculation messages.
The recent Spectre attacks have demonstrated the fundamental insecurity of current computer microarchitecture. The attacks use features like pipelining, out-of-order and speculation to extract ...arbitrary information about the memory contents of a process. A comprehensive formal microarchitectural model capable of representing the forms of out-of-order and speculative behavior that can meaningfully be implemented in a high performance pipelined architecture has not yet emerged. Such a model would be very useful, as it would allow the existence and non-existence of vulnerabilities, and soundness of countermeasures to be formally established. This paper presents such a model targeting single core processors. The model is intentionally very general and provides an infrastructure to define models of real CPUs. It incorporates microarchitectural features that underpin all known Spectre vulnerabilities. We use the model to elucidate the security of existing and new vulnerabilities, as well as to formally analyze the effectiveness of proposed countermeasures. Specifically, we discover three new (potential) vulnerabilities, including a new variant of Spectre v4, a vulnerability on speculative fetching, and a vulnerability on out-of-order execution, and analyze the effectiveness of existing countermeasures including constant time and serializing instructions.
•Roadway, environmental, and driver factors associated with ROR crashes were investigated.•The analysis was carried out using the rule discovery technique.•Data refer to the crashes occurred in the ...A16 motorway, Italy in the period 2001–2011.•The analysis provided new information which was previously hidden in the data.•Countermeasures to solve or mitigate the safety issues identified in the study were proposed.
The main objective of this paper was to analyse the roadway, environmental, and driver-related factors associated with an overrepresentation of frequency and severity of run-off-the-road (ROR) crashes. The data used in this study refer to the 6167 crashes occurred in the section Naples–Candela of A16 motorway, Italy in the period from 2001 to 2011. The analysis was carried out using the rule discovery technique due to its ability of extracting knowledge from large amounts of data previously unknown and indistinguishable by investigating patterns that occur together in a given event. The rules were filtered by support, confidence, lift, and validated by the lift increase criterion. A two-step analysis was carried out. In the first step, rules discovering factors contributing to ROR crashes were identified. In the second step, studying only ROR crashes, rules discovering factors contributing to severe and fatal injury (KSI) crashes were identified. As a result, 94 significant rules for ROR crashes and 129 significant rules for KSI crashes were identified. These rules represent several combinations of geometric design, roadside, barrier performance, crash dynamic, vehicle, environmental and drivers’ characteristics associated with an overrepresentation of frequency and severity of ROR crashes. From the methodological point of view, study results show that the a priori algorithm was effective in providing new information which was previously hidden in the data. Finally, several countermeasures to solve or mitigate the safety issues identified in this study were discussed. It is worthwhile to observe that the study showed a combination of factors contributing to the overrepresentation of frequency and severity of ROR crashes. Consequently, the implementation of a combination of countermeasures is recommended.
During the epidemic period, colleges and universities in China have launched online teaching practices. Online teaching can break through geographical restrictions, with flexible class times and ...locations, and students can watch it repeatedly after class, which is an important advantage compared with traditional classroom teaching. However, in teaching practice, the teaching effect of online teaching is not very good. Through literature research and interviews with teachers and students, it is found that the inconsistent and imperfect functions of online teaching platforms, the poor autonomy and self-discipline of students’ online learning, and the low online teaching ability of teachers are important factors that affect the effect of online teaching. Based on this, corresponding countermeasures from the perspectives of colleges, students and teachers are proposed to help the development of online teaching in the future and improve the effect of online teaching: First, to strengthen the support of colleges and universities for teaching platforms and course resources, and accelerate the construction of a stable and efficient unified online teaching platform. The second is to strengthen the guidance of students to enhance their autonomy and self-discipline in online learning. The third is to improve teachers’ online teaching level and information technology literacy to ensure the quality of online teaching.
•We develop a novel process perspective on NIHS based on the 4i framework of organizational learning.•We present a typology of NIHS countermeasures and explore their use in R&D practice.•We direct ...attention to a new class of indirect NIHS countermeasures.•We quantify the NIHS effect amounting to a 6.1% decrease in knowledge absorption for every one-point increase in NIHS.•We demonstrate the effectiveness of perspective taking as an indirect NIHS countermeasure.
This paper builds new theory and provides supporting evidence to contain the Not-Invented-Here Syndrome (NIHS) – a persistent decision-making error arising from an attitude-based bias against external knowledge. Conceptually, we draw on the 4i framework of organizational learning to develop a novel process perspective on NIHS. This allows us not only to unpack how and where NIHS impedes organizational learning, but also to identify the key requirements for effective NIHS countermeasures. Importantly, countermeasures fall into two categories: those that seek to change the negative attitude directly (direct NIHS countermeasures) and those that seek to attenuate the behavioral impact of negative attitudes without addressing the attitudes as such (indirect NIHS countermeasures). While the evidence base on direct NIHS countermeasures has grown over the last decade, indirect NIHS countermeasures have received little research attention. To address this gap, we adopt a mixed methods research design composed of two complementary empirical studies – the first qualitative and the second quantitative. Study 1 explores the prevalence of distinct NIHS countermeasures in collaborative R&D practice. Based on 32 interviews and three focus group meetings with R&D employees, we find that a broad array of primarily direct NIHS countermeasures is employed in R&D practice. Study 2 addresses the scarcity of scholarly and managerial insights on indirect NIHS countermeasures by testing the effectiveness of perspective taking as a debiasing technique to contain negative attitudes at the level of the individual. Based on quantitative survey data from 565 global R&D projects, it provides empirical evidence not only for the prevalence and negative effects of NIHS on project success as mediated by external knowledge absorption, but also for the effectiveness of perspective taking as an exemplary indirect NIHS countermeasure.
Cybersecurity is a growing concern for private individuals and professional entities. Reports have shown that the majority of cybersecurity incidents occur because users fail to behave securely. ...Research on human cybersecurity (HCS) behavior suggests that time pressure is one of the important driving factors behind non-secure HCS behavior. However, there is limited conceptual work to guide researchers and practitioners in this regard. Against this backdrop, we investigate how the impact of time pressure on HCS behavior can be conceptualized within an integrative framework and which countermeasures can be used to reduce its negative impact. Altogether, we conducted 35 interviews with cybersecurity experts, non-security professionals, and private users. The results of our study shed light on the theoretical pathways through which time pressure can affect different types of security behaviors and identify a range of operational, human, technical, and physical countermeasures with important implications for research and practice.
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