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This paper focuses on the new problem of urban vitality development, and designs 32 link indicators from 6 dimensions, including economy, talent, innovation, industry, people’s livelihood and international, to measure urban vitality by using comprehensive evaluation method. The results of the study show that (1) from the overall index, Jinan and Qingdao have been steadily ranked in the top two in the province; (2) from the time dimension of 2018-2022, cities such as Heze and Linyi have made the most obvious progress; Yantai and Weifang have performed more stable over the years. Based on the results of the study, the paper goes on to make a number of recommendations to provide a strategic basis for further improving urban vitality in Shandong.

In this article, based on the nonlinear elastic-plastic finite element model for metro station, considering the structure-soil dynamic interaction, the influence laws of the burial depth on the dynamic response and failure mode of the metro station structure under near and far-field earthquakes are studied. We found that the influence of burial depth on the deformation of the metro station may be omitted after a specific value of the burial depth. With the increasing of the burial depth, the acceleration dynamic amplification factors of the metro station structure decreses. At last, indoor shaking table test for metro station was done, through which we determined the position of initial failure and the failure mode of the metro station structure under earthquake.

Attacks in industrial control systems vary widely and are influenced by many factors, including the intent of the attacker, the capabilities of the attacker, the sophistication of the attacking techniques, and his familiarity with the industrial control systems and industrial processes. Attacks against industrial control systems are not a simple network intrusion, but are accomplished through a series of activities to achieve precise attack. This article expands the cyber kill chain model to improve it so that it can be applied to industrial control systems to ensure that defenders in industrial control can understand the attackers' attack activities so as to reasonably allocate limited security resources, take effective security measures and make well-informed risk management decision.

Inertia variations in servo systems greatly affect the control performance. This paper presents an adaptive terminal sliding-mode controller to deal with the problem. Instead of using traditional mathematics model, a characteristic model, which has more advantages in describing time-varying dynamics, is adopted to describe the servo system with inertia variations. The parameters of characteristic model are identified by the recursive least squares algorithm. Then, an adaptive terminal sliding-mode controller is designed based on the characteristic model. Theoretical analysis proves that the quasi-sliding mode is reached in finite steps. Simulation results demonstrate the improvement of tracking performance of the proposed controller.

SCADA (Supervisory Control and Data Acquisition) systems play a significant role in ICS (Industrial Control System). Safety, security and stable operation is crucial to the SCADA system. However, SCADA system currently faces many security threats, of which the most harmful is the APT attack. This paper analyzes the attack surface and its own vulnerabilities of SCADA system, and analyzes the characteristics of APT attack comprehensively. Then the paper dissects the cases of real APT attack thoroughly and gives measures of SCADA security protection.

With the arrival of Industry 4.0, more and more industrial control systems are connected with the outside world, which brings tremendous convenience to industrial production and control, and also introduces many potential security hazards. After a large number of attack cases analysis, we found that attacks in SCADA systems can be divided into internal attacks and external attacks. Both types of attacks are inevitable. Traditional firewalls, IDSs and IPSs are no longer suitable for industrial control systems. Therefore, we propose behavior-based anomaly detection and build three baselines of normal behaviors. Experiments show that using our proposed detection model, we can quickly detect a variety of attacks on SCADA (Supervisory Control And Data Acquisition) systems.

Attacks that use sophisticated and complex methods in-creased recently, aiming to infiltrate the Supervisory Control and Data Acquisition (SCADA) system and stay undetected. Therefore, attackers often get access to authorized permissions of SCADA and bring catastrophic damages by sending ‘legitimate’ control commands. Furthermore, insiders may also misuse or abuse their permissions to damage SCADA system, which is difficult to predict and protect against them. Most existing security systems employ standard signature-based or anomaly-based approaches, which are not able to identify this type of malicious activities. In this paper, we use machine learning algorithms based on Singular Values Decomposition (SVD) to create profiles of users and devices. The major contribution of this paper is providing a general process to detect anomalies, independent of specific use-cases. Suspicious actions are altered to analysts with relevant contextual information for further investigation and action. We provide detailed description of algorithms, methodology, processing of profiling and anomaly detection. Having profiles of different users and devices can provide us a baseline of normal behavior to compare against unusual behaviors. To demonstrate the proposed method, attack scenarios have been simulated at a Compressed Natural Gas (CNG) system in our lab. Experimental results illustrate that the proposed method is effective for abnormal behaviors in SCADA system.

In this paper, the wear test was carried on with cylinder piston by the wear test device, receiving the results of the piston ring wear and abrasive characteristics by monitoring the wear process, the thesis analysis and put forward the nano-CaCO3 lubricating oil additive anti wear mechanism by the ferrography analysis technology, and provide the technical reference for the relevant measures to reduce wear and the friction, and provide reference value for further study on the related theories of reducing wear and reducing friction.

The increasing use of common computer technologies in SCADA systems has brought convenience and at the same time introduced unprecedented security threats. SCADA system is becoming an attacker's target day by day. As attackers gain more understanding of industrial control systems, attacker's attack methods are more and more sophisticated, and the attack intensity is also increasing day by day. Faced with many security threats and risks, traditional security precautions cannot be effectively implemented. Therefore, this paper proposes an improved SCADA defense system, and evaluates it by using a variety of attacks. Experiments show that the defense-in-depth model we proposed is very effective against a variety of attacks.

With the raw materials of calix[4]arene, benzocaine, tricaine and procaine hydrochloride, three new azo calix[4]arene derivatives—6a, 6b and 6c are synthesized by diazotization–coupling reaction of an aromatic amine, with its yield of 83%, 81% and 83% respectively. The structural characterization is in a way of IR, 1H NMR and elemental analysis. This paper investigates the spectral properties of azo calix[4]arene derivatives under different solution pH conditions through the UV–visible spectroscopy, and researches the dyeing properties through the dyeing curve, color yield test and fastness test. The results show that, with the increase of pH value, the azo calix[4]arene derivatives—6a, 6b and 6c form azo–hydrazone tautomeric isomers with the maximum absorption peak redshift; the dyeing effect of the compound is good, of which the dye–uptake rate of the compound 6a is as high as 78%; the surface depth of color yield is 2.798, and the dry and wet rubbing fastness and the soaping fastness are respectively 4, which is a better disperse dye.