Backup Server Research Articles

A multi-period capacitated facility location problem with maximum travel time and backup service for locating and sizing EMS stations

Emergency medical services (EMS) is a system that provides emergency medical care for incidents involving serious illness or injury. The location of EMS stations plays an essential role in delivering effective and efficient medical services. Numerous location models have been developed for locating and sizing EMS stations. However, it remains challenging to satisfy all EMS planning criteria within a single location model. In this study, a multi-period capacitated facility location problem with maximum travel time and backup service (EMSLSP) is proposed for locating and sizing EMS stations. The most important criteria for EMS planning are taken into account in EMSLSP: the demand changes due to population mobility, the maximum service capacity of an ambulance, the maximum number of ambulances at each EMS station, the maximum travel time from each EMS station to the locations it serves, the full coverage of dynamic demand, the minimum percent of population covered by EMS service in a specific travel time, and a backup station for each demand location in case of need. A case study in Zhengzhou, a large city in China, demonstrates that effective and efficient locations and sizes of EMS stations can be determined by solving the EMSLSP with various planning parameters. Compared with the existing EMS systems, the average ambulance travel time and the percentage of the population served are significantly improved. Simulations of ambulance scheduling confirm that the relocated and resized EMS stations perform better than those in the existing system. The evaluation-optimization-simulation method outlined in this paper provides a comprehensive and effective approach for EMS station planning.

Strategy for scheduled downtime of hospital information system utilizing third-party applications

BackgroundThe widespread adoption of Hospital Information Systems (HIS) has brought significant benefits in healthcare quality and workflow efficiency. However, downtimes for system maintenance are inevitable and pose a considerable challenge to continuous patient care. Existing strategies, including manual prescription methods, are no longer effective due to increasing reliance on digital systems.MethodThis study implemented two main strategies to mitigate the impact of scheduled downtimes. First, we created an “Emergency query program” that switches to a read-only backup server during downtimes, allowing clinicians to view essential patient data. Second, an “Emergency prescription system” was developed based on the Microsoft Power Platform and integrated into Microsoft Teams. This allows clinicians to perform digital prescriptions even during downtimes.ResultsDuring a planned 90-minute downtime, 282 users accessed the Emergency Prescription System, resulting in 22 prescriptions from various departments. Average times for prescription confirmation and completion were 8 min and 3 s, and 18 min and 40 s, respectively. A post-downtime evaluation revealed high user satisfaction.ConclusionEssential maintenance-induced HIS downtimes are inherently disruptive to patient care process. Our deployment of an emergency query program and a Microsoft Teams-integrated emergency prescription system demonstrated robust care continuity during HIS downtime.

A Higher Performance Data Backup Scheme Based on Multi-Factor Authentication.

Remote data backup technology avoids the risk of data loss and tampering, and has higher security compared to local data backup solutions. However, the data transmission channel for remote data backup is not secure, and the backup server cannot be fully trusted, so users usually encrypt the data before uploading it to the remote server. As a result, how to protect this encryption key is crucial. We design a User-Centric Design (UCD) data backup scheme based on multi-factor authentication to protect this encryption key. Our scheme utilizes a secret sharing scheme to divide the encryption key into three parts, which are stored in the laptop, the smart card, and the server. The encryption key can be easily reconstructed from any two parts with user's private information password, identity and biometrics. As long as the biometrics has enough entropy, our scheme can resist replay attacks, impersonation user attacks, impersonation server attacks, malicious servers and offline password guessing attacks.

ОПТИМІЗАЦІЯ ПРОЦЕСІВ АВАРІЙНОГО ВІДНОВЛЕННЯ СЕРВІСІВ ІНФОРМАЦІЙНОЇ ІНФРАСТРУКТУРИ

The article describes the optimization of the process of disaster recovery of information infrastructure services by implementing the ability to restore service functionality without requiring a full recovery from backup storage. It outlines the criteria and parameters of the network that have a critical impact on recovery in the event of emergencies, allowing for the assessment of the solution's effectiveness in post-disaster recovery. A modification to the MTTR (Mean Time To Recovery) parameter is proposed for cases involving system element recovery from a backup or through service configuration restoration via infrastructure as code, with data necessary for service operation retrieved from backup storage, thereby accelerating the recovery process of a failed information infrastructure service. The article presents a scheme for infrastructure recovery organization by creating a backup location (Cold Site) for local infrastructure using dedicated cloud providers. The proposed solution utilizes Proxmox Backup Server capabilities for regular backups of critically important data center components. Following the development of a flowchart for the service recovery method from the Cold Site, research findings indicated that, for some services, reinstating configurations from code is more advantageous and speeds up the recovery process more than complete service restoration from backup storage.

Unavailability-Aware Backup Allocation Model Based on Two-Stage Shared Protection for Middleboxes

Middleboxes work as software which runs on a general-purpose server by adopting network function virtualization. The unavailability of middlebox is a key metric. The previous study considers allocating backup servers to middleboxes to reduce the unavailability. While it adopts shared protection to save backup capacity, resource sharing has not been sufficiently explored as each middlebox can only use one backup server. This paper presents a backup allocation model in which a function can be protected by two backup servers and a backup server can protect multiple functions under a shared protection strategy to minimize the maximum unavailability among functions. We use Markov chain to analyze the state transitions and make equilibrium-state equations. By solving them, we obtain the probability of each state of the allocation and compute an unavailability of function. We introduce two algorithms to examine the proposed model; one of them uses the performance bound of the maximum unavailability which is analyzed in this paper. Numerical results show that the proposed model reduces the maximum unavailability by 9.5–51.2% compared to a baseline model that allocates one backup server for each middlebox in our examined cases.

Supplementary variable technique approach on retrial queue with feedback and backup server during Bernoulli's lengthy vacation and random repairs.

Supplementary variable technique approach on retrial queue with feedback and backup server during Bernoulli's lengthy vacation and random repairs.

СПОСОБ ЗАЩИТЫ КОРПОРАТИВНОЙ СЕТИ НА ОСНОВЕ ДИНАМИЧЕСКОГО РАСПРЕДЕЛЕНИЯ ИНФОРМАЦИОННЫХ РЕСУРСОВ

The general trend in ensuring network security is the transition to the use of comprehensive information security systems. As the statistics of cyber attacks have shown, the objects of destructive influences, as a rule, are software and information resources of corporate networks. Within the framework of the well-known concept of comprehensive protection of network resources, the principle of situational transfer of information resources to protected nodes is substantiated. The article formulates the problem of dynamic distribution of local databases across nodes of a corporate information network. The implementation of such a mechanism is carried out in the event of a threat to the integrity of information resources by a priori formalization and initiation of an algorithm for solving the problem of assignments of a special type in Boolean variables. The features of the mathematical model of an extremal problem are the minimization of the cost of computing resources when solving a set of applied problems and taking into account the requirement for placing local databases on several network nodes with backup capabilities. In other words, a situationally formed plan for storing information resources involves placing one local database on at least the main and backup servers. The article considers the general methodology for determining the plan for placing databases on corporate network nodes and an example of its numerical implementation using the integer programming method. Based on the research results, recommendations are formulated consisting of choosing the optimal option for placing distributed database components on corporate network nodes, which ensures its full functionality and minimizes the risks of violating the integrity of information resources.

Current Situation and Engineering Application Prospect of Liquid Air Energy Storage Technology

Liquid air energy storage (LAES)technology is a new-coming energy storage method using cryogenic technology as basic theory. It managed to reach consumption of new energy in a grid-connected way, absorbing low power properly, and stable output of many other forms of energy like industrial gas and electricity. This paper introduces the technical principle and advantages of LAES, analyzes and discusses the problems faced by the development of LAES technology and the corresponding solutions, summarizes the applied fields of LAES technology. It also looks forward to the development direction of LAES technology. LAES has the advantages of high energy storage density and low storage pressure, and is less restricted by geographical conditions. It can store the remaining or discontinuous power for a certain time and produce stable power output. LAES technology has a wide range of application prospects in the power system, providing a variety of energy storage services and market opportunities for the power system, the industrial field, providing a variety of energy recovery, peak-valley balance, emergency backup and energy conversion services for industrial production, and urban gas systems, providing a variety of energy reserve, peak load emergency, emergency backup and auxiliary services for urban gas systems. It is of great significance to improve the phenomenon of "wind abandonment" and "light abandonment" in the power generation industry and meet the demand of "peak cutting and valley filling" in the power grid system.

Steering Angle Prediction From a Camera Image as a Backup Service

Steering Angle Prediction From a Camera Image as a Backup Service

DRIVE: Dynamic Resource Introspection and VNF Embedding for 5G Using Machine Learning

Network Slicing (NS) technique is comprehensively reshaping the next-generation communication networks (e.g. 5G, 6G). Software-Defined Networking (SDN) and Network Functions Virtualization (NFV) predominantly control the flow of service functions on NS to incorporate versatile applications as per user demands. In the virtualized-Software Defined Networking vSDN environment, a chain of well-defined virtual network functions (VNFs) are installed on Service Function Chains (SFCs) by multiple Internet Service Providers (ISPs) concurrently. Generation, allocation, re-allocation, release and destroying associative VNFs on SFC is an extremely difficult task while keeping high selection accuracy. Towards solving this fundamental issue, in this work, we have proposed a multi-layered SFC formation for adaptive VNF allocation on dynamic slices. We have formulated an ILP to address the VNF-EAP (VNF-Embedding and Allocation Problem) over real network topology (AT&T Topology). Leveraging machine learning techniques we have shown an intelligent VNF selection mechanism to optimize resource utilization. The performance evaluation shows remarkable efficiency on ML-driven dynamic VNF selections over static allocations on SFCs by halving resource usage. Further, we have also studied a VNF typecasting technique for service backup on outage slices in the field of disaster management activities.

Improving the Logistics of Institutional Postal Services

Postal services are often considered by the different institutions as a back-up service. Taking into account that in case of large geographical coverage these services can generate significant costs, it is important to optimize the postal service functions within these institutions and to develop the already existing conventional postal services. Within the frame of this article the authors review the logistics processes of the postal services at the University of Miskolc to propose improvements to the processes of postal services focusing on delivery. The main regulatory elements and the logistics processes of the institutional postal services are discussed and some critical remarks are described focusing on three main areas: the facility location optimization of the institutional postal services, the lack of use of modern technologies and the lack of modern administrative facilities. On the basis of these criticisms, the authors define recommendations for improving institutional postal services. Regarding the facility location optimization problem, a mathematical model and an optimization algorithm is described to evaluate the efficiency of the logistics processes of delivery services. The proposed methodology supports a cost-based analysis of different solution variants and a priority-based differentiation between institutions and offices. The suggested approach is tested with a real scenario, where the numerical results validate the efficiency of the evaluation of optimization algorithm. The second improvement direction is the application of a pneumatic tube system. The authors show the most important parts of the proposed pneumatic tube system, which can lead to decreased labor cost and increased service level.

Digital Repository as a Service (D-RaaS): Enhancing Access and Preservation of Cultural Heritage Artifacts

The employment of technology and digitization is crucial for cultural organizations to establish and sustain digital repositories for their cultural heritage artifacts. This exploitation is also essential in facilitating the presentation of cultural works and exhibits to a broader audience. Consequently, in this work, we propose a custom-developed digital repository that functions as software-as-a-service (SaaS), primarily promoting the safe storage, display, and sharing of cultural materials; enhancing accessibility; and fostering a deeper understanding and appreciation of cultural heritage. The proposed digital repository service is designed as a multitenant architecture, which enables organizations to expand their reach, enhance accessibility, foster collaboration, and ensure the preservation of their content. Moreover, our technology stack incorporates robust and reliable backend technologies, such as Django, to ensure data security and efficient management. Meanwhile, the frontend is powered by Angular, which guarantees a user-friendly and engaging interface for exploring and interacting with cultural materials. Specifically, this project aims to assist each cultural institution in organizing its digital cultural assets into collections and feeding other digital platforms, including educational, museum, pedagogical, and games, through appropriate interfaces. The creation of this digital repository offers a cutting-edge and effective open-access laboratory solution. It allows organizations to have a significant influence on their audiences by fostering cultural understanding and appreciation. Additionally, it facilitates the connection between different digital repositories and national/European aggregators, promoting collaboration and information sharing. By embracing this innovative solution, cultural institutions can benefit from shared resources and features, such as system updates, backup and recovery services, and data analytics tools, attributes that are currently provided by the platform.

Planning of reliable targeted evacuation under the threat of disasters

In planning evacuation services against the threat of disasters, it is important to optimize pickup point location and rescue vehicle routing decisions while recognizing the risks of service disruptions. In this paper, a reliable location and routing model with backup service plans is proposed to plan targeted strategic evacuation, which minimizes the total expected cost for deployment of pickup stations, rescue vehicle routing, and evacuee assignments and exposure while the service is subject to probabilistic disruptions. We formulate the problem as a mixed-integer non-linear program, and develop two customized solution algorithms, one based on Lagrangian relaxation (LR) and the other based on meta-heuristic, to decompose and solve the problem. Numerical experiments with various parameters are conducted to not only demonstrate the applicability of the proposed model and effectiveness of the solution algorithms, but also to draw managerial insights. The impacts of demand distribution, facility cost, disruption probability, and evacuee exposure risk are assessed in a series of sensitivity analyses, so as to inform agencies how to carefully consider these factors while developing a reliable targeted evacuation service plan.

Investigating the effect of virtual machine migration accounting on reliability using a cluster model

The purpose of the article is to develop and verify with the help of mathematical modeling a software method of deploying a fault-tolerant computing cluster with a virtual machine, which consists of two physical servers (main and backup), on which a distributed data storage system with synchronous data replication from the source server to the backup server is deployed. For this purpose, the task is to conduct a computational experiment on a model of a fault-tolerant cluster, which neglects costs during recovery for the migration of virtual machines by means of the mathematical application Mathcad. Combining computing resources into clusters is a way to ensure high reliability, fault tolerance, and continuity of the computing process of computer systems. This is achieved through virtualization, which enables the movement of virtual resources, services, or applications between physical servers while maintaining the continuity of computing processes. The focus of this study is on a failover cluster, which is composed of two physical servers (primary and backup) connected through a switch, and each server has a local hard disk. A distributed storage system with synchronous data replication from the source server to the backup server is deployed on the local disks of the servers, and a virtual machine is running on the cluster. Markovian processes, flows of podias, and Kolmogorov's systems of differential equations are built into the mathematical tools of the model of a water cluster. To ensure the continuity of the computing process in case of a failure of the main server, a shadow copy of the virtual machine is launched on the backup server. The reliability of the failover cluster is measured by the coefficient of non-stationary readiness. A Markov model is proposed to assess the reliability of the failover cluster, taking into account the costs of migrating virtual machines and mechanisms that ensure the continuity of the computing process in the cluster in case of a failure of one physical server. The memory migration process maintains two copies of the virtual machine on different physical servers, enabling them to continue working on the other in the event of failure. A simplified model of the failover cluster neglects the cost of migrating virtual machines and provides an upper estimate of reliability. The study shows that the reliability of a failover cluster, as measured by the non-stationary availability factor, is significantly impacted by the virtual machine migration process. The findings of this study can be used to inform decisions about the technology chosen to ensure the failure stability and continuity of the computing process of computer systems with cluster architecture. The calculations allow us to draw a conclusion about the significant impact of virtual machine migration accounting on reliability. The calculations allow us to draw a conclusion about the significant impact of virtual machine migration accounting on reliability. The calculation was performed under the following failure rates of the server, disk, and switch: λ0 = 1,115×10-5 1/h, λ1 = 3,425×10-6 1/h, λ2 = 2,3×10-6 1/h recovery respectively: μ0 = 0,33 1/h, μ1 = 0,171/h, μ2 = 0,33 1/h. The intensity of synchronization of the distributed storage system: μ3 = 1 1/h, μ4 = 2 1/h. The difference of non-stationary cluster availability coefficients is d = К2(t) – К1(t) = 2.7×10-10

Shared Backup Allocation Model of Middlebox Based on Workload-Dependent Failure Rate

With the network function virtualization technology, a middlebox can be deployed as software on commercial servers rather than on dedicated physical servers. A backup server is necessary to ensure the normal operation of the middlebox. The workload can affect the failure rate of backup server; the impact of workload-dependent failure rate on backup server allocation considering unavailability has not been extensively studied. This paper proposes a shared backup allocation model of middlebox with consideration of the workload-dependent failure rate of backup server. Backup resources on a backup server can be assigned to multiple functions. We observe that a function has four possible states and analyze the state transitions within the system. Through the queuing approach, we compute the probability of each function being available or unavailable for a certain assignment, and obtain the unavailability of each function. The proposed model is designed to find an assignment that minimizes the maximum unavailability among functions. We develop a simulated annealing algorithm to solve this problem. We evaluate and compare the performances of proposed and baseline models under different experimental conditions. Based on the results, we observe that, compared to the baseline model, the proposed model reduces the maximum unavailability by an average of 29% in our examined cases.

Secure Role Based Access Control Data Sharing Approach and Cloud Environment

the primary objective of cloud storage is to maintain data integrity, which involves implementing measures to prevent unauthorized access and ensuring that data can be regenerated if mishandled. To achieve this, a proxy server will be assigned the task of protecting and restoring data in case of unauthorized modifications. Users' data will be stored in both public and private areas of the cloud, with only public data being accessible to users and private data being kept more secure. Cloud storage offers users various redundancy configurations to balance performance and fault tolerance, with data availability being critical in distributed storage systems, especially when node failures are common in real-life scenarios. In this research, a proposed aes 128 encryption algorithm and role-based access control (rbac) scheme are explored to provide secure data storage and sharing, as well as a secure user access policy. Additionally, a backup server approach is used as a proxy storage server for ad hoc data recovery for all distributed data servers. The experiment's analysis is proposed in both public and private cloud environments, utilizing keywords such as rbac, elgamal encryption scheme, proxy key generation, advanced encryption standard (aes), and more

Endovascular Closure of Secundum Atrial Septal Defects with Complex Anatomy

According to European guidelines, endovascular closure is the method of choice for defects with favorable anatomy. However, there are no clear criteria for determining favorable anatomy and this issue requires additional investigation. According to literature data, only 24.2% of secundum atrial septal defects (ASDII) have a central location, others have complicated anatomy.
 The aim. To analyze the experience of endovascular closure of ASDII with complex anatomy. Materials. In the period from 2003 to 2021, 1732 transesophageal echocardiographies and intracardiac echocardiographieswereperformedinpatientswithASDIIinitiallydiagnosedaccordingtotransthoracicechocardiography, and only 1408 (91.8%) were selected for endovascular closure. Mean age was 19.9±18 years, mean weight was 45±26.68 kg.
 Methods. The standard closure technique was primarily used in 100% of cases, and only when it was ineffective, we used modified techniques.
 Results. Modified techniques were used in 478 (33.9%) of 1408 patients and were effective in 460 (96.2%) patients with the complex anatomy. Based on previous statement, 460 (32.6%) of 1408 patients (one third of all) had modified techniques utilized and avoided open surgery. In 18 (1.3%) cases, it was impossible to close the defect. The overall technical success of transcatheter closure was 98.7% (1390 patients). Nineteen (1.3%) patients with poor visualization of inferior rim on transesophageal echocardiography had intracardiac echocardiography; in two of them inferior rim was present, others had open surgery. The rate of complications in immediate periprocedural period was 1.9% (27 patients). One death was recorded in the period of introduction of percutaneous interventions in our institution. Mean follow-up period was 5.41±3.28 years. In the follow-up period two complications were observed: 1 case of erosion, 17 (1.9%) cases of new-onset atrial fibrillation.
 Conclusion. The majority (90.6%) of ASDII can be closed percutaneously. Modified techniques improve the efficacy of the procedure enabling to close 32.6% of the defects. Safe procedure for the defects with complex anatomy is possible only with surgical and arrhythmological services back-up.

Study on the VCRplus Back-Up Roll Contour of 1500 mm CVC Mill

The back-up rolls of hot strip mills wear considerably under the conditions of high temperature and heavy load, which affects the roll service period and the stability of strip profile control. Serious uneven wear, short service periods, and spalling problems occurred on conventional back-up rolls of upstream stand CVC mills in 1500 mm continuous hot rolling production lines. Through finite element simulations, the problems are determined to be caused by the configuration of a flat roll contour of the back-up roll and the CVC roll contour of the work roll, which leads to uneven contact pressure between the rolls. The wear distribution form is ‘anti-CVC’ shape, and there is peak contact pressure between the rolls on both sides of the roll body. In particular, the long-term negative shifting of CVC on site further increases the peak contact pressure between the rolls, resulting in uneven wear and spalling accident. Based on the design technology of VCR back-up roll contours with variable contact lengths, and considering the cooperation between the middle of the back-up roll and the CVC work roll contour, the roll contour of the back-up roll has been improved. The designed VCRplus roll contour was analyzed and evaluated by finite element simulation, including the distribution of contact pressure between rolls, the control effect of bending force, and the transverse stiffness of the roll gap. The simulation results show that the VCRplus roll contour can effectively improve the uneven distribution of contact pressure between the rolls, and effectively improve the control effect of bending force and the transverse stiffness of the roll gap. Industrial tests demonstrate that VCRplus back-up roll contours have the advantages of uniform back-up roll wear, enhanced self-sustaining of the roll contour, and further extension of the back-up roll service life. The roll contour has now stably been put into industrial production, and the rolling capacity during the back-up roll service period has been extended from 150,000,000 kg to 250,000,000 kg.

Implementation of the elements of the enterprise protection system

The article defines the main tasks and features of corporate information networks and analyzes the specifics of the corporate network implemented in a medical center. The proposed data protection system at the enterprise is developed on the basis of the Bella-La Padula model since the key provisions of this model are the assignment of special security levels to all participants in the protected data processing process and to the documents in which it is contained. The specified security levels are arranged using the established dominance relationship, and the access control is carried out depending on the security levels of the interacting parties, which allows the application of technical solutions of the Active Directory service. One of the elements to ensure data protection is the use of a Shadow Copy of data according to the appropriate schedule. An important component of ensuring data protection is the individual process of setting up group policies and checking replication with other servers running the Active Directory directory services of the medical center. As a result of the implementation of elements of the company's data protection system, it was possible to significantly increase the level of protection and set up a backup server, on which appropriate folders were created, to which backup copies would be made according to the schedule. This function makes it possible to save the history of changes in any file for a certain period. The proposed elements of the security system can be used to analyze the security system, control access, ensure data integrity, etc. The Active Directory directory services were implemented in the medical center, and data replication to a backup server was configured. Taking into account the specifics of the enterprise, namely the medical center, the implemented elements of the data protection system ensure the delimitation of access levels, implement protection profiles and secure the personal data of patients.

Information Preservation and Restore Strategies for the Cloud Era

Computing in the cloud is the method that is most frequently employed by companies for the purpose of storing huge volumes of data. In the data-driven society that we live in today, a significant amount of data is produced each day. You are going to need data backup and recovery services in the event that you suffer an unplanned loss of these files. Here, we examine a variety of data-protection methods in order to compare and contrast their respective merits and downsides and to better understand the innovative aspects of each technique.