Neural Network-Based State Estimation for Nonlinear Systems With Denial-of-Service Attack Under Try-Once-Discard Protocol

Dear Editor,This letter deals with state estimation issues of discrete-time nonlinear systems subject to denial-of-service(DoS)attacks under the try-once-discard(TOD)protocol.More specifically,to reduce the communication burden,a TOD protocol with novel update rules on protocol weights is designed for scheduling measurement outputs.In addition,unknown nonlinear functions vulnerable to DoS attacks are considered due to the openness and vulnerability of the network.

Unity of Knowing and Doing

Chinese President Xi Jinping has emphasized the unity of knowing and doing on a number of occasions,saying that knowing is the premise,while doing is putting knowledge to work,and these two ideas have a mutually reinforcing relationship.UNITY of knowing and doing is a key concept in ancient Chinese philosophy.Discussions on knowing and doing can be traced back to the pre-Qin period(before 221 B.C.).

Understanding the Pt-like Catalytic Activity of Transition Metal Carbide Ta4C_(3) for I_(3)^(-) Reduction

This paper attempts to understand the Pt-like catalytic activity of transition metal carbide Ta4C_(3) for IRR(I_(3)^(-)reduction reaction)based on the correlation of adsorption energy to d-band center(εd).Ta4C_(3) was prepared by carbothermal reduction method with a template.Its photoelectrochemical properties were investigated as a CE(counter electrode)in DSSC(dye-sensitized solar cell).Its surface electronic structures,including DOS(density of state)andεd,and adsorption energy were computed by first-principle DFT(density functional theory).In TMC(transition metal carbide)Ta4C_(3),the interaction between Ta and C atoms makes the d-band of Ta broaden and results in the downward shift of itsεd.A moderate absorption energy corresponding to theεd is achieved,which is the nature of the Pt-like catalytic activity of Ta4C_(3).Appropriate change of adsorption energy by adjustingεd is a promising strategy to improve catalytic activity.This work is of great significance to the fundamental and application researches.

The Influence of Chuang Tsu on Oscar Wilde’s Literary Works

Oscar Wilde,the renowned British writer,was deeply influenced by Eastern culture,particularly by Chuang Tsu’s“Thought of Doing Nothing”,a Taoist concept of human conduct.Wilde not only embraced this philosophy,but also incorporated it into his literary creations and art criticism,enhancing the steadfastness of his own value judgments.

Obtaining 2D Soil Geotechnical Profiles from Cokriging Interpolation of Sample Data and Electrical Resistivity Tomography (ERT)—Applications in Mass Movements Studies

Brazil annually faces significant challenges with mass movements, particularly in areas with poorly constructed housing, inadequate engineering, and lacking sanitation infrastructure. Campos do Jordão, in São Paulo state, is a city currently grappling with these issues. This paper details a study conducted within a pilot area in Campos do Jordão, where geophysical surveys and geotechnical borehole data were integrated. The geophysical surveys provided 2D profiles, and samples were collected to analyse soil moisture and plasticity. These datasets were combined using a Cokriging-based model to produce an accurate representation of the subsurface conditions. The enhanced modelling of subsurface variability facilitates a deeper understanding of soil behavior, which can be used to improve landslide risk assessments. This approach is innovative, particularly within the international context where similar studies often do not address the complexities associated with urban planning deficits such as those observed in some areas of Brazil. These conditions, including the lack of proper sanitation and irregular housing, significantly influence the geological stability of the region, adding layers of complexity to subsurface assessments. Adapting geotechnical evaluation methods to local challenges offers the potential to increase the efficacy and relevance of geological risk management in regions with similar socio-economic and urban characteristics.

Distributed Dimensionality Reduction Filtering for CPSs Under DoS Attacks

Dear Editor,This letter concerns about the distributed dimensionally reduction filtering for a class of cyber physical systems with denial of service(DoS)attacks.Considering each sensor exchanging measurements with neighbors subjected to finite network energy,the dimensionally reduction method is applied.

Epidemiological Profile of Men Who Have Sex with Men: First Data about Male Sex Workers in Central African Republic (CAR)

Objectives: Sex work is not well documented among African men. The aim of this study was to describe the epidemiological profile of men who have sex with men (MSM) and eventually to determine the proportion of sex workers (SW) among them, as well as the proportion of MSM who have been victims of gender-based violence (GBV). Material and Methods: A cross-sectional study coordinated by the Direction de la Médecine du Travail was carried out at the headquarters of the association ALTERNATIVES in Bangui Bangui from July 1 to October 31, 2021. Consenting MSM present during the study period were systematically included. Sociodemographic variables, those relating to the future vision of the activity and to GBV were collected and analyzed using Epi-Info version 7 software. Results: Forty MSM with an average age of 23 years and mainly secondary education (75.0%) were included. The vast majority of MSM were unemployed (85.0%). 45.0% had been victims of GBV and wanted to stop working as an MSM (47.5%), and almost 2/3 (65.0%) would accept another income-generating activity in exchange for the MSM. Violence was sexual (32.5%), economic (22.5%), physical (20.0%), verbal (12.5%) and psychological (12.5%). Conclusion: The MSM were mainly young, poorly educated, unemployed, and almost half were victims of GBV. The desire to change MSM activity to another income-generating activity alongside that of MSM shows that many of them are SW, workers in the informal sector. This must be taken into account in prevention activities, even if the data needs to be confirmed on a much larger sample.

Cyberattack Ramifications, The Hidden Cost of a Security Breach

In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain.

Social Rights and Work on Digital Platforms in Brazil:The Case of“Breque dos Apps”

The movement known as“Breque dos Apps”was a social movement of a striker nature,which took place in Brazil in July 2020.Such movement was organized by workers which provided services to delivery apps(like iFood,Loggi,Uber Eats and Rappi).They demanded better working conditions and social protection measures,since they were out of the protection of the Brazilian legal system.The reason for this lies in the fact that there is a debate about the classification of these workers-the maximum expression of the gig economy-as employees under Brazilian legislation.As a result,and with the exponential growth in the use of these applications due to the Covid-19 pandemic,thousands of workers were left on the fringes of any social protection.This study aims to analyze the aforementioned movement and its demands within the paradigm of social rights,especially the ones regarding collective representation,which are guaranteed by the Brazilian Constitution.In terms of methodology,the content analysis method will be applied,considering that the established objective presupposes the study of theoretical and legal texts that allow the structuring of concepts applicable to the theme.The research technique to be adopted will be the analysis of indirect documentation,that is,literature review,to be carried out through bibliographic and documentary research,focused on literature and legal texts related to the topic.

Do Not Resuscitate status as an independent risk factor for patients undergoing surgery for hip fracture

AIM To determine morbidity and mortality in this specific patient group and also to assess for any independent associations between Do Not Resuscitate(DNR) status and increased post-operative morbidity and mortality.METHODS We conducted a propensity score matched retrospective analysis using de-identified data from the American College of Surgeons' National Surgical Quality Improvement Project(ACS NSQIP) for all patients undergoing hip fracture surgery over a 7 year period in hospitals across the United States enrolled in ACS NSQIP with and without Do Not Resuscitate Status. We measured patient demographics including DNR status, co-morbidities, frailty and functional baseline, surgical and anaestheticprocedure data, post-operative morbidity/complications, length of stay, discharge destination and mortality.RESULTS Of 9218 patients meeting the inclusion criteria, 13.6% had a DNR status, 86.4% did not. Mortality was higher in the DNR status compared to the non-DNR group, at 15.3% vs 8.1% and propensity score matched multivariable analysis demonstrated that DNR status was independently associated with mortality(OR = 2.04, 95%CI: 1.46-2.86, P < 0.001). Additionally, analysis of the propensity score matched cohort demonstrated that DNR status was associated with a significant, but very small increased likelihood of post-operative complications(0.53 vs 0.43 complications per episode; OR = 1.21; 95%CI: 1.04-1.41, P = 0.004). Cardiopulmonary resuscitation and unplanned reintubation were significantly less likely in patients with DNR status.CONCLUSION Whilst DNR status patients had higher rates of postoperative complications and mortality, DNR status itself was not otherwise associated with increased morbidity. DNR status appears to increase 30-d mortality via ceilings of care in keeping with a DNR status, including withholding reintubation and cardiopulmonary resuscitation.

Modelling Key Population Attrition in the HIV and AIDS Programme in Kenya Using Random Survival Forests with Synthetic Minority Oversampling Technique-Nominal Continuous

HIV and AIDS has continued to be a major public health concern, and hence one of the epidemics that the world resolved to end by 2030 as highlighted in sustainable development goals (SDGs). A colossal amount of effort has been taken to reduce new HIV infections, but there are still a significant number of new infections reported. HIV prevalence is more skewed towards the key population who include female sex workers (FSW), men who have sex with men (MSM), and people who inject drugs (PWID). The study design was retrospective and focused on key population enrolled in a comprehensive HIV and AIDS programme by the Kenya Red Cross Society from July 2019 to June 2021. Individuals who were either lost to follow up, defaulted (dropped out, transferred out, or relocated) or died were classified as attrition;while those who were active and alive by the end of the study were classified as retention. The study used density analysis to determine the spatial differences of key population attrition in the 19 targeted counties, and used Kilifi county as an example to map attrition cases in smaller administrative areas (sub-county level). The study used synthetic minority oversampling technique-nominal continuous (SMOTE-NC) to balance the datasets since the cases of attrition were much less than retention. The random survival forests model was then fitted to the balanced dataset. The model correctly identified attrition cases using the predicted ensemble mortality and their survival time using the estimated Kaplan-Meier survival function. The predictive performance of the model was strong and way better than random chance with concordance indices greater than 0.75.

终末期癌症患者签署Do-Not-Resuscitate现状及影响因素分析

在终末期癌症患者的姑息治疗中,拒绝心肺复苏(Do-Not-Resuscitate,DNR)签署是最为重要和关键的部分。探讨了DNR在终末期癌症患者中签署的现状及相关因素的分析,建议在加强DNR的宣传教育及推广的同时,更好地保护患者对疾病的知情同意权,鼓励患者更多参与到癌症的诊断、治疗及终末期生命终结方式的讨论中来,尽早地与患者及家属进行DNR的沟通,使得患者在癌症终末期能得到最佳的、及时的姑息性支持治疗。

Resilient and Safe Platooning Control of Connected Automated Vehicles Against Intermittent Denial-of-Service Attacks

Connected automated vehicles(CAVs)serve as a promising enabler for future intelligent transportation systems because of their capabilities in improving traffic efficiency and driving safety,and reducing fuel consumption and vehicle emissions.A fundamental issue in CAVs is platooning control that empowers a convoy of CAVs to be cooperatively maneuvered with desired longitudinal spacings and identical velocities on roads.This paper addresses the issue of resilient and safe platooning control of CAVs subject to intermittent denial-of-service(DoS)attacks that disrupt vehicle-to-vehicle communications.First,a heterogeneous and uncertain vehicle longitudinal dynamic model is presented to accommodate a variety of uncertainties,including diverse vehicle masses and engine inertial delays,unknown and nonlinear resistance forces,and a dynamic platoon leader.Then,a resilient and safe distributed longitudinal platooning control law is constructed with an aim to preserve simultaneous individual vehicle stability,attack resilience,platoon safety and scalability.Furthermore,a numerically efficient offline design algorithm for determining the desired platoon control law is developed,under which the platoon resilience against DoS attacks can be maximized but the anticipated stability,safety and scalability requirements remain preserved.Finally,extensive numerical experiments are provided to substantiate the efficacy of the proposed platooning method.

Secure Synchronization Control for a Class of Cyber-Physical Systems With Unknown Dynamics

This paper investigates the secure synchronization control problem for a class of cyber-physical systems(CPSs)with unknown system matrices and intermittent denial-of-service(DoS)attacks.For the attack free case,an optimal control law consisting of a feedback control and a compensated feedforward control is proposed to achieve the synchronization,and the feedback control gain matrix is learned by iteratively solving an algebraic Riccati equation(ARE).For considering the attack cases,it is difficult to perform the stability analysis of the synchronization errors by using the existing Lyapunov function method due to the presence of unknown system matrices.In order to overcome this difficulty,a matrix polynomial replacement method is given and it is shown that,the proposed optimal control law can still guarantee the asymptotical convergence of synchronization errors if two inequality conditions related with the DoS attacks hold.Finally,two examples are given to illustrate the effectiveness of the proposed approaches.

First principles study on Mn-doped LiFePO_4 as cathode material for rechargeable lithium batteries

The electronic structure and diffusion energy barriers of Li ions in pure and Mn-doped LiFePO4 have been studied using density functional theory(DFT).The results demonstrate clearly that Fe-O covalent bond is weaker than P-O covalent bond.Pure LiFePO4 has band gap of 0.56 eV and diffusion energy barrier of 2.57 eV for Li ions,while the dopant has small band gap of 0.25 eV and low diffusion energy barrier of 2.31 eV,which indicates that the electronic and ionic conductivity of LiFePO4 have been improved owing to doping.

Phytoremediation Potential of Three Species of Macrophytes for Nitrate in Contaminated Water

Three species of aquatic plants (Scirpus validus, Phragmites australis and Acorus calamus) were used as experimental materials to study their capacity to purify contaminated water and their effects on water pH and dissolved oxygen (DO). The water was contaminated with different concentrations of nitrate (5 mg/L, 15 mg/L and 25 mg/L). The results indicated that the concentration of nitrate, species of aquatic plant and their interaction significantly impacted denitrification (P = 0.00). Under the same concentrations, the three species of aquatic plants provided varying degrees of purification. Acorus calamus provided effective purification under all three concentrations of nitrate wastewater, with removal percentages of 87.73%, 83.80% and 86.72% for nitrate concentrations of 5 mg/L, 15 mg/L and 25 mg/L, respectively. In terms of the purification ability by unit fresh weight, Acorus calamus exhibited the worst purification capacity, whereas the capacities of Scirpus validus and Phragmites australis were higher. The purification capacity of Scirpus validus for the three concentrations was as follows: 0.08 mg/(L&middot;g FW), 0.29 mg/(L&middot;g FW), and 0.51 mg/(L&middot;g FW). The capacity of Phragmites australis was 0.07 mg/(L&middot;g FW), 0.25 mg/(L&middot;g FW), and 0.53 mg/(L&middot;g FW). The capacity of Acorus calamus was 0.04 mg/(L&middot;g FW), 0.12 mg/(L&middot;g FW), and 0.21 mg/(L&middot;g FW). Under increased concentrations of nitrate, the three species of aquatic plants exhibited various degrees of increased purification capacity. Under the different concentrations of nitrate, the three species exhibited the same trends with respect to water pH and DO, increasing first and then falling. The pH remained at approximately 7.5, and the DO fell to 4.0 mg/L. A comprehensive analysis reveals that Acorus calamus provides excellent nitrate purification, although by unit fresh weight, both Scirpus validus and Phragmites australis provide superior purification capacity.

Intelligent DoS Attack Detection with Congestion Control Technique for VANETs

VehicularAd hoc Network(VANET)has become an integral part of Intelligent Transportation Systems(ITS)in today’s life.VANET is a network that can be heavily scaled up with a number of vehicles and road side units that keep fluctuating in real world.VANET is susceptible to security issues,particularly DoS attacks,owing to maximum unpredictability in location.So,effective identification and the classification of attacks have become the major requirements for secure data transmission in VANET.At the same time,congestion control is also one of the key research problems in VANET which aims at minimizing the time expended on roads and calculating travel time as well as waiting time at intersections,for a traveler.With this motivation,the current research paper presents an intelligent DoS attack detection with Congestion Control(IDoS-CC)technique for VANET.The presented IDoSCC technique involves two-stage processes namely,Teaching and Learning Based Optimization(TLBO)-based Congestion Control(TLBO-CC)and Gated Recurrent Unit(GRU)-based DoS detection(GRU-DoSD).The goal of IDoS-CC technique is to reduce the level of congestion and detect the attacks that exist in the network.TLBO algorithm is also involved in IDoS-CC technique for optimization of the routes taken by vehicles via traffic signals and to minimize the congestion on a particular route instantaneously so as to assure minimal fuel utilization.TLBO is applied to avoid congestion on roadways.Besides,GRU-DoSD model is employed as a classification model to effectively discriminate the compromised and genuine vehicles in the network.The outcomes from a series of simulation analyses highlight the supremacy of the proposed IDoS-CC technique as it reduced the congestion and successfully identified the DoS attacks in network.

SGuard：A Lightweight SDN Safe-Guard Architecture for DoS Attacks

Software Defined Networking(SDN) is a revolutionary networking paradigm towards the future network,experiencing rapid development nowadays.However,its main characteristic,the separation of control plane and data plane,also brings about new security challenges,i.e.,Denial-of-Service(DoS) attacks specific to Open Flow SDN networks to exhaust the control plane bandwidth and overload the buffer memory of Open Flow switch.To mitigate the DoS attacks in the Open Flow networks,we design and implement SGuard,a security application on top of the NOX controller that mainly contains two modules:Access control module and Classification module.We employ novel six-tuple as feature vector to classify traffic flows,meanwhile optimizing classification by feature ranking and selecting algorithms.All the modules will cooperate with each other to complete a series of tasks such as authorization,classification and so on.At the end of this paper,we experimentally use Mininet to evaluate SGuard in a software environment.The results show that SGuard works efficiently and accurately without adding more overhead to the SDN networks.

Security Control for Uncertain Networked Control Systems under DoS Attacks and Fading Channels

This paper characterizes the joint effects of plant uncertainty,Denial-of-Service(DoS)attacks,and fading channel on the stabilization problem of networked control systems(NCSs).It is assumed that the controller remotely controls the plant and the control input is transmitted over a fading channel.Meanwhile,considering the sustained attack cycle and frequency of DoS attacks are random,the packet-loss caused by DoS attacks is modelled by a Markov process.The sampled-data NCS is transformed into a stochastic form with Markov jump and uncertain parameter.Then,based on Lyapunov functional method,linear matrix inequality(LMI)-based sufficient conditions are presented to ensure the stability of uncertain NCSs.The main contribution of this article lies in the construction of NCSs based on DoS attacks into Markov jump system(MJS)and the joint consideration of fading channel and plant uncertainty.

A W-EAP Algorithm for IEC 61850 Protocol against DoS/Replay Attack

Substation automation system uses IEC 61850 protocol for the data transmission between different equipment manufacturers. However, the IEC 61850 protocol lacks an authentication security mechanism, which will make the communication face four threats: eavesdropping, interception, forgery, and alteration. In order to verify the IEC 61850 protocol communication problems, we used the simulation software to build the main operating equipment in the IEC 61850 network environment of the communication system. We verified IEC 61850 transmission protocol security defects, under DoS attack and Reply attack. In order to enhance security agreement, an improved algorithm was proposed based on identity authentication (W-EAP, Whitelist Based ECC & AES Protocol). Experimental results showed that the method can enhance the ability to resist attacks.