Failure Recovery Research Articles

FAPR: An Adaptive Approach to Link Failure Recovery in SDN with High Speed and Low Interruption Rate

FAPR: An Adaptive Approach to Link Failure Recovery in SDN with High Speed and Low Interruption Rate

Development of a novel seismic acquisition system based on fully autonomous ocean bottom nodes

It is now established that ocean bottom node (OBN) surveys provide superior seismic data compared to traditional towed streamers, but deployment of the nodes is time-consuming and expensive. As an alternative, we are developing a novel seismic acquisition system that utilises a fleet of fully autonomous underwater vehicles (AUVs) as OBNs. The objective is to eliminate the reliance on remotely operated vehicles (ROVs) or ropes for deployment, making ocean bottom seismic acquisition significantly more efficient and cost-effective. To succeed, several criteria need to be met, including recording of good geophysical data, system affordability, low power consumption, units’ ability to act autonomously (e.g. steer, land, listen, re-position, surface) and to respond to remote commands (e.g. cease activity, return), a failure recovery protocol, automated deployment and retrieval, and system-wide communications. The ability to record good seismic data was assessed in October 2022, when we performed active-source seismic field trials in the UK. Five AUVs were deployed adjacent to commercial nodes (all units carried identical geophysical payloads) and a series of 2D lines were acquired at varying orientations. Analysis of the data confirmed that our units achieved satisfactory coupling with the seabed. The unit’s in-water capabilities were assessed during multiple field trials in 2022 and 2023, offshore UK and Australia. Tests consisted of simulating seismic acquisition cycle (flights, landings, take-offs and repositioning) where it was verified that missions were reliably executed, including landing within 10 m from pre-planned locations and recording good quality passive seismic data.

Organizational learning from failures: double moderating impact of organizational trust and owner-manager interest in human resource development

ABSTRACT This study examines how organisational learning processes, such as learning stocks, learning flows, and external learning affect Korean small- and medium-sized enterprises’ (SMEs) perceived recovery and organisational performance through learning from failure. The double moderated mediation impact of organisational trust and owner-managers’ interest in human resource development (HRD) in these relationships has been tested. About 400 SMEs were selected and a self-reported online survey was administered. Among them, 296 SMEs were analysed based on their experience in employee development. All three organisational learning activities have an impact on perceived failure recovery and organisational performance through learning from failure. Additionally, organisational trust and owner-managers’ interest in HRD moderates the relationship between organisational learning activities. However, owner-managers’ interest in HRD has a negative moderating effect, indicating that power-political relationships impede learning from failure. Using the method of self-reporting to identify the role of organisational learning from failure, this study addresses the lack of empirical research with an integrated approach on this topic. The findings have several academic and practical implications. Owner-managers must engage in various developmental activities to build trust among members and should create space and time where employees feel free to share ideas and reflect on their opinions.

Practicable live container migrations in high performance computing clouds: Diskless, iterative, and connection-persistent

Checkpoint/Restore techniques had been thoroughly used by the High Performance Computing (HPC) community in the context of failure recovery. Given the current trend in HPC to use containerization to obtain fast, customized, portable, flexible, and reproducible deployments of their workloads, as well as efficient and reliable sharing and management of HPC Cloud infrastructures, there is a need to integrate Checkpoint/Restore with containerization in such a way that the freeze time of the application is minimal and live migrations are practicable. Whereas current Checkpoint/Restore tools (such as CRIU) support several options to accomplish this, most of them are rarely exploited in HPC Clouds and, consequently, their potential impact on the performance is barely known. Therefore, this paper explores the use of CRIU’s advanced features to implement diskless, iterative (pre-copy and post-copy) migrations of containers with external network namespaces and established TCP connections, so that memory-intensive and connection-persistent HPC applications can live-migrate. Our extensive experiments to characterize the performance impact of those features demonstrate that properly-configured live migrations incur low application downtime and memory/disk usage and are indeed feasible in containerized HPC Clouds.

Research on resilience assessment method of train control on-board system

To address the problem of difficult performance assessment of train control on-board system after recovery from failures, we have proposed a resilience assessment methodology that uses reliability as an indicator of system resilience. Since the system failures are time-dependent, we adopted the Discrete Time Bayesian Network method to obtain the system's reliability before and after failure. Subsequently, we used an exponential recovery model to quantify the system's performance curve during the recovery phase, and finally utilized the resilient triangle area method to quantify its resilience size. Analyzing the CTCS3-300T train control on-board system, we found that the resilience of the system with cold standby redundancy design and hot standby redundancy design were 89.44 % and 87.34 %, respectively, indicating a slight decrease in system performance after recovery from failures compared to pre-failure levels. At that time, it was necessary to adjust operational plans based on actual conditions to avoid greater impact on the railway network. This paper realizes performance resilience of train control on-board system after failure recovery, which can be applied to similar systems and provide theoretical references for realizing intelligent maintenance of the high-speed train.

The Impact of Microvascular Resistance Reserve on the Outcome of Patients With STEMI

BackgroundMicrovascular resistance reserve (MRR) can characterize coronary microvascular dysfunction (CMD); however, its prognostic impact in ST-segment elevation myocardial infarction (STEMI) patients remains undefined. ObjectivesThis study sought to investigate the prevalence of CMD in STEMI patients and to elucidate the prognostic performance of MRR. MethodsThis prospective cohort study enrolled 210 STEMI patients with multivessel disease who underwent successful revascularization and returned at 3 months for coronary physiology assessments with bolus thermodilution. The prevalence of CMD (MRR <3) and the association between MRR and major adverse cardiovascular and cerebrovascular events (MACCEs) at 12 months were investigated. ResultsThe median age of patients was 65 years, and 59.5% were men. At the 3-month follow-up, 56 patients (27%) had CMD (MRR <3.0). The number of MACCEs at 12 months was higher in patients with vs without CMD (48.2% vs 11.0%; P < 0.001). MRR was independently associated with 12-month MACCEs (HR: 0.45 per unit increase; 95% CI: 0.31-0.67; P < 0.001) and with stroke, heart failure, and poorer recovery in left ventricular systolic function. The areas under the receiver-operating characteristic curves for predicting MACCEs at 12 months with fractional flow reserve, coronary flow reserve (CFR), the index of microvascular resistance (IMR), and MRR were 0.609, 0.762, 0.781, and 0.743, respectively. The prognostic performance of CFR, IMR, and MRR were all comparable. ConclusionsThe novel parameter MRR is a prognostic marker of MACCEs in STEMI patients with a comparable performance to CFR and IMR. (Impact of TMAO Serum Levels on Hyperemic IMR in STEMI Patients [TAMIR]; NCT05406297)

(174) - Persistent Alterations in Gene Expression Despite Phenotypic Normalization in a Non-Ischemic Mouse Model of Heart Failure Recovery: Are ECM and Ferroptosis Genes the Key for Complete, Sustained Recovery?

(174) - Persistent Alterations in Gene Expression Despite Phenotypic Normalization in a Non-Ischemic Mouse Model of Heart Failure Recovery: Are ECM and Ferroptosis Genes the Key for Complete, Sustained Recovery?

Failure recovery in the MANTRA architecture with an IPoWDM SONiC node and 400ZR/ZR+ pluggables

The utilization of IP over wavelength division multiplexing (IPoWDM) boxes in optical networks introduces coordination issues at the control plane level between the optical and packet domains. Indeed, IPoWDM boxes are technically packet devices, but the configuration of coherent optical pluggables requires knowledge of optical network state information (e.g., wavelength availability). MANTRA (metaverse ready architectures for open transport) aims to define a new SDN control architecture for managing IPoWDM, enhancing coordination between the packet and optical controllers. Within MANTRA, two distinct architectures were presented: Dual and Single. However, only the roles related to controller management are defined, while clear procedures are not specified for dealing with resource provisioning and failure recovery. This leads to the need for the definition and implementation of tailored procedures. Besides the characterization of the coherent optical pluggables performance, this paper presents and compares three procedures based on MANTRA to coordinate and control IPoWDM nodes in a multi-layer network performing failure recovery. The considered solutions have been designed and experimentally validated with a focus on the achievable traffic recovery performance considering IPoWDM configuration and communication within the SDN control architecture. An experimental testbed, comprising a sliced IPoWDM node running an extended version of the open-source SONiC network operating system, has been deployed to validate these solutions, with a comprehensive analysis of the time required to recover a real traffic flow that spans both the packet and optical domains.

Failure recovery mechanism for BDI agents based on abilities and discovery protocols

Failure recovery mechanism for BDI agents based on abilities and discovery protocols

Correlation of T2DM and Anthropometric Measures with Total Small Bowel Length and Its Effects on Diabetes Remission After Bariatric Surgery.

The outcome of weight loss surgery is related to several factors, and for super-obese patients, the rate of weight loss failure and weight recovery after Roux-en-Y gastric bypass (RYGB) is high. Relevant studies have shown that the weight loss effect also correlates with total small bowel length (TSBL) and biliopancreatic (BP) and Roux limbs. However, there are few studies on the relationship between TSBL and anthropometric parameters, the BP limb, the Roux limb, and weight loss effect, and no relevant reports have been reported in China. The objective was to study the relationship between the total length of the small intestine and anthropometric parameters in the Chinese population. The effect of the Roux limb/biliopancreatic limb (RL/BPL) ratio on weight loss and diabetes remission in RYGB patients 1year after surgery was evaluated to find the appropriate ratio relationship. In this prospective study, 148 patients between the ages of 19 and 68years who underwent laparoscopic Roux-en-Y gastric bypass were enrolled. Height, weight, BMI, the BP limb, the Roux limb, fasting blood glucose (FBG), etc., were noted. To explore the correlation between the total length of the small intestine and these values. Subsequently, the 148 patients were followed up for 1year after surgery. The patients diagnosed with T2DM before surgery were screened out, and 56 patients were finally identified according to the postoperative follow-up, in which BPL = 50cm and RL = 150cm, 175cm, and 200cm, respectively. RL/BPL was divided into 3, 3.5, and 4 groups according to the proportional relationship to explore the relationship between RL/BPL and diabetes remission and weight loss. (1) The study included 148 patients (61 women and 87 men). The mean age was 35.68 ± 10.46years, weight = 127.46 ± 34.51kg, height = 167.83 ± 9.16cm, BMI = 44.94 ± 10.58kg/m2. The average TSBL value was 714.41 ± 101.08 cm. Linear regression analysis showed that TSBL was positively correlated with height, weight, neck circumference, chest circumference, waist circumference, and Roux limb. (2) Fifty-six patients with T2DM who were followed up 1year after surgery were divided into three groups. Group 1: BPL = 50cm, RL = 150cm (n = 20); group 2: BPL = 50cm, RL = 175cm (n = 26); group 3: BPL = 50cm, RL = 200cm (n = 10); RL/BPL = 3 was associated with higher weight loss than the other groups. The remission rate of diabetes did not differ between the three groups. TSBL was positively correlated with height, weight, neck circumference, chest circumference, waist circumference, and Roux limb. The TSBL of males was significantly higher than that of females. Among patients with T2DM who participated in the follow-up 1year after surgery, RL/BPL = 3 (n = 20) had greater weight loss than the other groups.

Abnormal data detection and recovery of sensors network based on spatiotemporal deep learning methodology

This paper proposes a novel deep-learning-enabled framework for abnormal data detection and recovery considering spatial-temporal correlation among sensors. The wavelet scattering transform is adopted to replace the first layer of one-dimension convolutional neural network classification model. The multiple typical sensor failure modes of sensor are identified including bias, drifting, gain, precision degradation, and three complete faults (constant; constant + noise; noise). The bidirectional long-short time memory (BLSTM) network is developed to recover abnormal data through positive and negative propagation. The BLSTM cell involving forget, input, and output gate is utilized to adaptively transmit valuable information of long-term data. Different sensor configurations are conducted to select the optimal input sensors of BLSTM model. The proposed models are then validated by three engineering cases. The results show that the failure mode diagnosis and recovery accuracy are over 90 %. Sensor selection has a large impact on the data reconstruction, and selecting sensors with higher correlation can achieve a higher accuracy. In addition, the data recovery accuracy of the proposed BLSTM model surpasses that of traditional long-short time memory models.

Entrepreneurial intentions of tourism and hospitality students in Ghana: an application of the theory of planned behaviour

PurposeThe study aims to examine the entrepreneurial intentions (EIs) of tourism and hospitality (T&H) students in Ghana using the theory of planned behaviour (TPB). Specifically, the study examined the role of university support on students’ EIs and behaviour within the framework of TPB.Design/methodology/approachAn online questionnaire was used to collect data from 929 T&H students from six universities in Ghana. Structural equation modelling using AMOS was used to test the stated hypotheses.FindingsThe results showed that perceived university support (PUS) played a key role in influencing students’ attitudes, subjective norms and behavioural controls towards their EIs. Furthermore, the EI of T&H students was also found to have influenced students’ entrepreneurial behaviours (EBs). All seven hypotheses were significant.Research limitations/implicationsTo increase the entrepreneurial drive of T&H students, universities and T&H educators need to provide support through strengthening experiential learning activities (guest speaker series, mentorship sessions, practicals and internships) to provide an avenue for students to be trained on risk management and failure recovery skills, develop positive attitudes and behaviours and learn from experts. Policymakers should also enact favourable laws to regulate business practices.Originality/valueThis is likely the first paper to address the issue of PUS for entrepreneurship amongst T&H students in the context of a developing country. Specifically, it addresses the role of universities and T&H educators in supporting T&H students to be entrepreneurs.

An efficient failure-resilient mutual exclusion algorithm for distributed systems leveraging a novel zero-message overlay structure

In this paper, we provide a novel failure-resilient token-based mutual exclusion (ME) algorithm for distributed systems. Like a few other solutions in the literature, the proposed solution leverages a logical tree as its underlying topology. However, unlike any other solution, the tree is built using a probabilistic, fully distributed approach, without exchanging messages. The current tree-based ME algorithms often overlook considerations for node/link failures or offer costly methods for failure recovery. The proposed algorithm overcomes these limitations by providing an effective solution to maintain a logarithmic cost in case of node failures. The overlay structure – a unique logical tree – used to control access to the critical section maintains its consistency even when nodes fail. An extensive simulation study demonstrates the viability and efficiency of the proposed algorithm under various node failure models, and relevant metrics (e.g., node queue dimension, number of exchanged messages, and number of disconnected nodes) indicate a graceful degradation in performance with decreasing number of functioning nodes. For instance, for 4,096 nodes organized in a logical tree of arity 4 and with 4 physical nodes for logical node, a negligible number of nodes is disconnected from the tree after 250 epochs when the per-node per-epoch failure probability is pf≤0.0008. With a pf=0.0016, less than 10% of the nodes are disconnected. The proposed algorithm avoids node disconnection while minimally impacting the load of the logical tree nodes. In addition, for the same architecture, when both tree arity and cardinality are 4, after 250 epochs, the node load has demonstrated minimal variation and remains in close proximity to the original load. Moreover, experimental results also reveal a graceful degradation of algorithm performance. The fully distributed solution, rich parametrization for different trade-offs, and viability and resilience of the proposed algorithm also pave the way for future research.

Online Guaranteed Reachable Set Approximation for Systems With Changed Dynamics and Control Authority

This work presents a method of efficiently computing inner and outer approximations of forward reachable sets for nonlinear control systems with changed dynamics and control authority, given an a priori computed reachable set for the nominal system. The method functions by shrinking or inflating a precomputed reachable set based on prior knowledge of the system's trajectory deviation growth dynamics, depending on whether an inner approximation or outer approximation is desired. These dynamics determine an upper bound on the minimal deviation between two trajectories emanating from the same point that are generated by control inputs from the nominal and diminished set of control inputs, respectively. The dynamics depend on the given Hausdorff distance bound between the nominal set of admissible controls and the possibly unknown impaired space of admissible controls. Because of its computational efficiency compared to direct computation of the off-nominal reachable set, this procedure can be applied to on-board fault-tolerant path planning and failure recovery. In addition, the proposed algorithm does not require convexity of the reachable sets unlike our previous work, thereby making it suitable for general use. We raise a number of implementational considerations for our algorithm, and we present three illustrative examples, namely an application to the heading dynamics of a ship, a lower triangular dynamical system, and a system of coupled linear subsystems.

Analysis of interlocking faults and reliability evaluation methods for communication networks of power information physical systems

The information physics system realizes the integration and interaction between them by the 3C technique. The application of scheduling automation, Substation Automation and Online Fault Recovery Technology Improves Emergency Response Capability, and Information Security issues are also embedded in the energy system. Power grid operation is facing more threats, and state space and failure scenarios are also more abundant, which poses new research needs and challenges for power system stability assessment. First, the physical interaction of information is analyzed. From the perspective of function, the CPPS hierarchy corresponds to the physical Electric power system, the information sub-station system and the main station system respectively. Then, taking the information node as the fault detection sample point, the chain fault model of the power information physical system is studied, and the abnormal response of the power information system is classified and identified, Finally, a failure response model and a failure recovery model are built. Finally, a simulation example is given for verification.

Service failure recovery on customer recovery satisfaction and attitude loyalty for airline industry: the moderating effect of brand authenticity

Service failure recovery on customer recovery satisfaction and attitude loyalty for airline industry: the moderating effect of brand authenticity

TUBER: Time-aware UAV-based energy-efficient reconfigurable routing scheme for smart wireless livestock sensor network.

This paper is a follow-up to a recent work by the authors on recoverable UAV-based energy-efficient reconfigurable routing (RUBER) scheme for addressing sensor node and route failure issues in smart wireless livestock sensor networks. Time complexity and processing cost issues connected to the RUBER scheme are consequently treated in this article by proffering a time-aware UAV-based energy-efficient reconfigurable routing (TUBER) scheme. TUBER scheme employs a synchronized clustering-with-backup strategy, a minimum-hop neighborhood recovery mechanism, and a redundancy minimization technique. Comparative network performance of TUBER was investigated and evaluated with respect to RUBER and UAV-based energy-efficient reconfigurable routing (UBER) schemes. The metrics adopted for this comparative performance analysis are Cluster Survival Ratio (CSR), Network Stability (NST), Energy Dissipation Ratio (EDR), Network Coverage (COV), Packet Delivery Ratio (PDR), Fault Tolerance Index (FTI), Load Balancing Ratio (LBR), Routing Overhead (ROH), Average Routing Delay (ARD), Failure Detection Ratio (FDR), and Failure Recovery Ratio (FRR). With reference to best-obtained values, TUBER demonstrated improvements of 36.25%, 24.81%, 34.53%, 15.65%, 38.32%, 61.07%, 31.66%, 63.20%, 68.96%, 66.19%, and 78.63% over RUBER and UBER in terms of CSR, NST, EDR, COV, PDR, FTI, LBR, ROH, ARD, FDR, and FRR, respectively. These experimental results confirmed the relative effectiveness of TUBER against the compared routing schemes.

Rapid Recover Map Reduce (RR-MR): Boosting failure recovery in Big Data applications

Rapid Recover Map Reduce (RR-MR): Boosting failure recovery in Big Data applications

Therapeutic Plasma Exchange in Children With Acute and Acuteon-Chronic Liver Failure: A Single-Center Experience.

Acute liver failure is a life-threatening condition that may result in death if liver transplant is not performed. The aim of our study was to evaluate patients with acute liver failure or acute-on-chronic liver failure who were followed and treated with therapeutic plasma exchange in a pediatric intensive care unit until they achieved clinical recovery or underwent liver transplant. In this retrospective, singlecenter study, we included patients with acute liver failure or acute-on-chronic liver failure who received therapeutic plasma exchange between April 2020 and December 2021. Clinical findings, laboratory findings, extracorporeal therapies, Pediatric Risk of Mortality III and liver injury unit scores and pretherapy and posttherapy hepatic encephalopathy scores, Model for End-Stage Liver Disease score, and Pediatric End-Stage Liver Disease score were retrospectively analyzed. Nineteen patients were included in the study. One patient was excluded because of positivity for COVID-19. The mean age of children was 62.06 months, ranging from 5 months to 16 years (12 boys, 6 girls). Thirteen patients (72.2%) had acute liver failure, and 5 patients (27.8%) had acute-on-chronic liver failure. No significant difference was shown for mean liver injury unit score (P = .673) and Pediatric Logistic Organ Dysfunction score (P = .168) between patients who died and patients who received treatment at the inpatient clinic and transplant center. However, Pediatric Risk of Mortality score and the mean Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease scores before therapeutic plasma exchange and after therapeutic plasma exchange (after 3 consecutive days of treatment) were statistically significant (P = .001 and P = .004). Therapeutic plasma exchange may assist bridge to liver transplant or assist with spontaneous recovery of liver failure in pediatric patients with acute liver failure or acute-on-chronic liver failure.

Protocol for fever control using external cooling in mechanically ventilated patients with septic shock: SEPSISCOOL II randomised controlled trial

IntroductionFever treatment is commonly applied in patients with sepsis but its impact on survival remains undetermined. Patients with respiratory and haemodynamic failure are at the highest risk for not tolerating...