Additional Links Research Articles

Comparative analysis of 2D mesh topologies with additional communication links for on-chip networks

Multiprocessor system-on-chip (MPSoC) is playing a vital role in recent embedded technologies. One of the main challenges of this system is its communication bottleneck which limits performance scaling capabilities. In order to overcome this restriction, on-chip interconnection networks have been proposed. Several topologies have been suggested in the literature, but the most popular one remains the mesh topology due to its systematic and scalable design structure. Although, the functionality and performance of network-based mesh topologies degrade significantly with growing system size, which results in the network diameter and the dependency on small bisection width. A wide range of modified designs has been proposed in the literature with various types of additional links to improve the network performance. However, these links result in additional cost overhead on the system in terms of area, energy, and power consumption. Among the selected competitor meshes, it is observed that the link design of d-Torus produces high performance at elevated communication costs. The design of the CBP-Torus is less complex and results in lower communication costs compared to d-Torus with similar performance. The selection of an appropriate mesh-type topology of the target application is, therefore, a tradeoff between the performance and cost of the network. This paper analyzes the impact of additional links on the performance of on-chip mesh architectures. The comparative analysis includes performance characteristics, structural complexity, power consumption, and area utilization. This research work provides a roadmap for the designers to choose the most appropriate topology for a particular design.

QUALITY MANAGEMENT OF BUSINESS PROCESSES IN THE CONTEXT OF ACHIEVING SUSTAINABLE DEVELOPMENT OF FASHION INDUSTRY ENTERPRISES

INTRODUCTION. Sustainable development and victory in competition in the conditions of globalization and international division of labor can be ensured by enterprises that manage the quality of business processes on a systematic basis, which makes it possible to produce high-quality, environmentally safe products in an ethical way.
 THE PURPOSE OF THE STUDY is the further development of methodological, methodical and practical approaches to the management of the quality of business processes of a fashion industry enterprise in the context of its achieving sustainable development.
 RESEARCH METHODS. The research used scientific methods of theoretical generalization, analysis, synthesis, induction and deduction, structural-logical analysis, historical method.
 RESULT. The high quality of products and services plays a decisive role in achieving sustainable development of the enterprise. The relationship between sustainable development and quality management at the evolution stages of enterprises and organizations is considered. Four stages have been identified, which correspond to organizational models, determined by a combination of the following features: closed – open system; rational – social thinking. The place of quality management and sustainable development in each organization’s model is determined. The quality chain reaction of E. Deming was supplemented and expanded with additional links of ecological and social component and it was shown that high product quality leads to a positive economic, social and ecological effect, i.e. ensures the sustainable development of the enterprise. The special role of the ecological component of sustainable development is highlighted. In order to avoid and counteract environmental threats, enterprises carry out rational nature management measures and processes of ecologically balanced development. The indicators of environmental protection activities in Ukraine 2016–2020 were reviewed.
 CONCLUSIONS. Sustainable development is the driver of quality management of business processes at the enterprise, which is confirmed by the logical chain of quality improvement influence on the economic, environmental and social components of sustainable development of the producer. The organization model in the period of open systems and social individual ensures comprehensive quality management and sustainable development of the enterprise. The quality management system of business processes at a fashion industry enterprise, which meets the requirements of the international standard ISO 9001: 2015, is a tool for realizing the goals of sustainable development of the enterprise.
 KEYWORDS: sustainable development; quality; quality management; business process quality management system; E. Deming's chain; environmental protection activity.

DEVELOPMENT OF APPLIED ONTOLOGY FOR THE ANALYSIS OF DIGITAL CRIMINAL CRIME

Context. A feature of the modern digital world is that crime is often committed thanks to the latest computer technologies, and the work of law enforcement agencies faces a number of complex challenges in the digital environment. The development of information technology and Internet communications creates new opportunities for criminals who use digital traces and evidence to commit crimes, which complicates the process of identifying and tracking them.
 Objective. Development of an applied ontology for a system for analyzing a digital criminal offense, which will effectively analyze, process and interpret a large amount of digital data. It will help to cope with the complex task of processing digital data, and will also help automate the process of discovering new knowledge.
 Methods. To build an ontological model as a means of reflecting knowledge about digital crime, information was collected on existing international and domestic classifications. The needs and requirements that must be satisfied by the developed ontology were also analyzed. The creation of an ontological model that reflects the basic concepts, relationships in the field of digital criminal offense was carried out in accordance with a recognized ontological analysis of a specialized subject area.
 Results. An applied ontology contains the definition of entities, properties, classes, subclasses, etc., as well as the creation of semantic relationships between them. At the center of the semantics is the Digital Crime class, the problem area of which is complemented by the interrelated classes Intruder, Digital evidence, Types of Crime, and Criminal liability. Such characteristics as motive, type of crime, method of commission, classification signs of digital traces and types of crime, as well as other individual information were assigned to the attributes of the corresponding classes. An ontological model was implemented in OWL using the Protégé software tool. A feature of the implementation of the applied ontology was the creation of SWRL rules for automatically filling in additional links between a class instance. Manual and automatic verification of the ontology showed the integrity, consistency, a high degree of correctness and adequacy of the model. The bugs found were usually related to technical aspects and semantic inconsistencies, which were corrected during further development iterations.
 Conclusions. The research confirmed the effectiveness of the developed applied ontology for the analysis of digital criminality, providing more accurate and faster results compared to traditional approaches.

Global patterns and drivers of dissolved organic matter across Earth systems: insights from H/C and O/C ratios

Dissolved organic matter (DOM) is ubiquitous and contains a complex pool of thousands of distinct molecules, and their chemical characteristics help us inform the fate of global carbon. However, a more holistic perspective of the molecular characteristics of DOM and underlying mechanisms across Earth systems and climates remains under study. Here, we present a comprehensive analysis of the molecular characteristics of DOM using two abundance-weighted average indices, i.e., H/C and O/C ratios, by compiling 2,995 samples from 317 studies covering waters, land, plant, petroleum, and atmosphere systems and climatic regions from the tropics to tundra. H/C ratios are lower on average in waters (H/C = 1.15 ± 0.005) and land (H/C = 1.20 ± 0.010) than in the other systems, while their O/C ratios rank between plant and atmosphere systems. In the waters and land systems, the H/C ratios of DOM vary from the highest to the lowest in the habitats of the land-to-ocean continuum generally as snow > glacier > marine ≥ freshwater/soil > groundwater. The H/C ratios show predictably U-shaped patterns along latitudinal gradients, indicating the lowest abundance of more hydrogen-saturated molecules at mid-latitudes of approximately 40°-50° in river water, lake water, and forest soil. The two ratios are primarily controlled by environmental factors such as pH, dissolved oxygen, and carbon and nitrogen contents. We further unveil additional and considerable links between the ratios and the extremes of climatic factors such as precipitation of warmest quarter and maximum temperature of warmest month. Our synthesis provides molecular-level perspectives to characterize the global distribution and underlying drivers of DOM, which is complementary for our understanding of global carbon cycle processes under future global change.

Показатели оксидативного стресса и дисфункции эндотелия при сахарном диабете 2-го типа: риски и фокус на диетотерапию

Type 2 diabetes (T2D) is a chronic metabolic disease that poses a significant threat to public health worldwide. Carbohydrate metabolism disorders in T2D are closely related to oxidative stress. Numerous vascular complications are the main cause of disability and mortality in this disease. Objective. Comparative evaluation of the indices of oxidative stress and endothelial dysfunction with anthropometric and biochemical parameters in T2D patients. Patients and methods. The study included 55 patients with T2D and 58 patients with class 1–3 obesity without diabetes. Patients with T2D received a standard treatment with oral sugar-lowering drugs, hypolipidemic and hypotensive therapy as indicated. All patients underwent measurements of anthropometric parameters (height, weight, body mass index), indices of carbohydrate and lipid metabolism, antioxidant status and endothelial dysfunction, triglycerides-glucose index, and pulse wave velocity. Statistical processing of the results was performed using SPSS 23.0 software. Results. Several correlations were found between oxidative stress indices and clinical and metabolic parameters characterizing the state of carbohydrate and lipid metabolism and anthropometric indices in patients with T2D. The level of high-sensitivity C-reactive protein was almost twice as high in T2D patients compared to patients with obesity (11.1 ± 2.58 mg/L and 6.77 ± 1.11 mg/L, respectively). A negative correlation between the levels of superoxide dismutase and fasting blood glucose was determined (r = -0.30, p < 0.005). Conclusion. The study revealed a strong correlation between oxidative stress indices, markers of endothelial dysfunction and cardiometabolic disorders in patients with T2D. The influence on oxidative stress/antioxidant defense indices may become an additional therapeutic link in the treatment of T2D patients. Key words: reactive oxygen species, endothelial dysfunction, oxidative stress, type 2 diabetes

Synaptopodin-2 Isoforms Have Specific Binding Partners and Display Distinct, Muscle Cell Type-Specific Expression Patterns.

Synaptopodin-2 (SYNPO2) is a protein associated with the Z-disc in striated muscle cells. It interacts with α-actinin and filamin C, playing a role in Z-disc maintenance under stress by chaperone-assisted selective autophagy (CASA). In smooth muscle cells, SYNPO2 is a component of dense bodies. Furthermore, it has been proposed to play a role in tumor cell proliferation and metastasis in many different kinds of cancers. Alternative transcription start sites and alternative splicing predict the expression of six putative SYNPO2 isoforms differing by extended amino- and/or carboxy-termini. Our analyses at mRNA and protein levels revealed differential expression of SYNPO2 isoforms in cardiac, skeletal and smooth muscle cells. We identified synemin, an intermediate filament protein, as a novel binding partner of the PDZ-domain in the amino-terminal extension of the isoforms mainly expressed in cardiac and smooth muscle cells, and demonstrated colocalization of SYNPO2 and synemin in both cell types. A carboxy-terminal extension, mainly expressed in smooth muscle cells, is sufficient for association with dense bodies and interacts with α-actinin. SYNPO2 therefore represents an additional and novel link between intermediate filaments and the Z-discs in cardiomyocytes and dense bodies in smooth muscle cells, respectively. In pathological skeletal muscle samples, we identified SYNPO2 in the central and intermediate zones of target fibers of patients with neurogenic muscular atrophy, and in nemaline bodies. Our findings help to understand distinct functions of individual SYNPO2 isoforms in different muscle tissues, but also in tumor pathology.

The specificity of the prop in the comic book on the example of Andi Watson’s The Book Tour

In comics, similar to theatre or film, props play a crucial role in storytelling. However, in the comic medium, the function of a prop as a meaningful element takes on a distinct character. Cartoons not only depict objects but also give them specific significance through artistic representation. The article aims to explore this phenomenon by examining the graphic novel The Book Tour by Andi Watson. The analysis draws upon the insights of renowned comics scholars but also refers to broader conceptual frameworks. Thus additional links to theoretical proposals on the semiotics of visual representations and semiotics of the stage. Throughout the discussion, the paper presents artistic techniques used by Andi Watson that contribute to the unique nature and the way of functioning of comic props.

Frozen Base Gateway Discovery Algorithm for Mobile Ad-Hock Network with Internet Connectivity Using AODV + Routing Algorithm

A mobile ad-hoc network (MANET) is a self-organized, auto-configured network and the mobile nodes have been free to move. To enable the MANET to connect to the internet it uses an intermediate bridge called a gateway. The MANET and the internet gateway is a heterogeneous network, which needs a gateway discovery. There are three types of gateway discovery mechanisms: proactive, reactive, and hybrid gateway discovery mechanism. The main challenge in the integration of the MANET and the Internet is, that there are high link disconnection results from node mobility and limited energy. In addition link disconnection, packet drop, and end-to-end delay. This study examines the impact of node mobility and energy in the frozen path from the source node to the destination node of MANET In this study, the Ad-hoc on-demand distance vector routing (AODV) routing protocol is used and modified to examine the gateway selection for MANET and the Internet. Moreover, the AODV+ control message RREQ and RREP and the routing table are improved to store the energy factor, path queue length, and frozen factor of the path. The proposed gateway discovery algorithm is known as frozen-based gateway AODV+ (F_AODV+), The stability factors of the path from the source node to the gateway, are calculated using a simple additive weighting method of the energy factor, average path queue node, and the path with the Maximum energy factor and minimum queue length is the more Frozen to select Frozen gateway from the source node to distension node.A mobile ad-hoc network (MANET) is a self-organized, auto-configured network and the mobile nodes have been free to move. To enable the MANET to connect to the internet it uses an intermediate bridge called a gateway. The MANET and the internet gateway is a heterogeneous network, which needs a gateway discovery. There are three types of gateway discovery mechanisms: proactive, reactive, and hybrid gateway discovery mechanism. The main challenge in the integration of the MANET and the Internet is, that there are high link disconnection results from node mobility and limited energy. In addition link disconnection, packet drop, and end-to-end delay. This study examines the impact of node mobility and energy in the frozen path from the source node to the destination node of MANET In this study, the Ad-hoc on-demand distance vector routing (AODV) routing protocol is used and modified to examine the gateway selection for MANET and the Internet. Moreover, the AODV+ control message RREQ and RREP and the routing table are improved to store the energy factor, path queue length, and frozen factor of the path. The proposed gateway discovery algorithm is known as frozen-based gateway AODV+ (F_AODV+), The stability factors of the path from the source node to the gateway, are calculated using a simple additive weighting method of the energy factor, average path queue node, and the path with the Maximum energy factor and minimum queue length is the more Frozen to select Frozen gateway from the source node to distension node.

Reliably Controlling Massive Traffic between a Sensor Network End Internet of Things Device Environment and a Hub Using Transmission Control Protocol Mechanisms

The constant growth of Internet of Things traffic is ensured by the ongoing evolution of the hierarchy of all hardware links of sensor networks. At the same time, the implementation of the Edge computing ideology regulates the complexity of the “first-mile” section (from the sensors array to the peripheral server). Here, the authors suggest paying attention to the growing share of massive traffic from target sensors in the total traffic of the sensors array. This circumstance makes it expedient to introduce an additional link to the peripheral server for summarizing massive traffic from target sensors. The authors present a sensor network end IoT device (SNEIoTD), implemented grounded on a reliable and cheap Raspberry Pi computing platform, as such a link. The introduction of this SNEIoTD makes it possible to reduce the probability of information loss from the critical infrastructure of a smart city and increase the flexibility of controlling the massive traffic of the first mile. In this context, the urgent task is the reliable control of information transfer from the SNEIoTD environment to a hub, which the authors formalize based on Transmission Control Protocol (TCP). This article proposes a mathematical model of the interaction of the main mechanisms of the TCP in the form of a queuing system. As part of this model, a semi-Markov process of an information transfer with a unified speed is selected and its stationary distribution is analytically formalized. A computationally efficient information technology for determining the TCP Window Size is formulated, taking into account the interaction of TCP mechanisms in the process of massive traffic control. Using the example of TCP Westwood+ protocol modification, it is shown that the results of the application of information technology permit increases in the stability of data transfer under the circumstances of increasing Round-Trip Times.

The dynamic analysis of fixed deep-water platform

The industrial progress is closely related with active using of hydrocarbons more than half of reserves of which lie in rock formations beneath seabed or ocean floor. For oil production at the great depth of immersion oil production fixed platforms are used most often. But using of such technological structures is not limited only to interest of oil and natural gas industry whereas they are important for navigation and military purposes. Offshore fixed platforms are exposed to effects of a high seismicity, wind, waves, strong undercurrents and an impulse impact during the movement of ice fields especially when exploitation in northern seas. The impact of different factors on the value of the period of natural oscillations ofthe offshore fixed deep-water ice-resistant platform with the depth of immersion 120 m that rests on the pile foundation was researched. Two discrete idealized models of the platform were used for the analysis: the first model that was implemented without taking into account the flexibility of the foundation and the second model where the flexibility of the pile foundation and the action of ground foundation were taking into account by the addition of elastic links that simulate the elastic connection between joints. Also, impacts of the connected mass of water media that was modeled in the form of additional distributed joints mass and the impact of the ice field that was modeled by the addition of additional links were investigated. The analysis showsthat values of periods of natural oscillations form increase by 8-20% when the flexibility of the pile foundation was taken into account; increase by 9-100% when the impact of the connected mass of water media was taken into account; decrease by 9-100% when the impact of the ice field and water media were taken into accountthat is significant when analyzing of stress-strain state of members of the structure.

Sobolev regularity of Gaussian random fields

In this article, we fully characterize the measurable Gaussian processes (U(x))x∈D whose sample paths lie in the Sobolev space of integer order Wm,p(D),m∈N0,1<p<+∞, where D is an arbitrary open set of Rd. The result is phrased in terms of a form of Sobolev regularity of the covariance function on the diagonal. This is then linked to the existence of suitable Mercer or otherwise nuclear decompositions of the integral operators associated to the covariance function and its cross-derivatives. In the Hilbert case p=2, additional links are made w.r.t. the Mercer decompositions of the said integral operators, their trace and the imbedding of the RKHS in Wm,2(D). We provide simple examples and partially recover recent results pertaining to the Sobolev regularity of Gaussian processes.

ENRN: A System for Evaluating Network Resilience against Natural Disasters

The frequency and severity of natural disasters is surging, posing an urgent need for robust communication network infrastructure that is capable of withstanding these events. In this paper, we present a groundbreaking graph-theoretic system designed to evaluate and enhance network resilience in the face of natural disasters. Our solution harnesses the power of topological robustness metrics, integrating real-time weather data, geographic information, detailed network topology data, advanced resilience algorithms, and continuous network monitoring. The proposed scheme considers four major real-world U.S.-based network providers and evaluates their physical topologies against two major hurricanes. Our novel framework quantifies the important characteristics of network infrastructure; for instance, AT&amp;T is identified to have fared better against Hurricane Ivan (57.98 points) than Hurricane Katrina (39.17 points). We not only provide current insights into network infrastructure resilience, but also uncover valuable findings that shed light on the performance of backbone U.S. networks during hurricanes. Furthermore, our findings provide actionable insights to enrich the overall survivability and functionality of communication networks, mitigating the adverse impacts of natural disasters on communication systems and critical services in terms of improving network resiliency via adding additional nodes and link or rewiring.

Analysis of multiple overlapping paths algorithms for secure key exchange in large-scale quantum networks

Quantum networks open the way to an unprecedented level of communication security. However, due to physical limitations on the distances of quantum links, current implementations of quantum networks are unavoidably equipped with trusted nodes. Consequently, the quantum key distribution can be performed only on the links. Due to this, some new authentication and key exchange schemes must be considered to fully benefit from the unconditional security of the links. One such approach uses Multiple Non-Overlapping Paths (MNOPs) for key exchange to mitigate the risk of an attack on a trusted node. The scope of the article is to perform a security analysis of this scheme for the case of both uncorrelated attacks and correlated attacks with finite resources. Furthermore, our analysis is extended to the case of Multiple Overlapping Paths (MOPs). We prove that introducing overlapping paths allows one to increase the security of the protocol, compared to the non-overlapping case with the same number of additional links added. This result may find application in optimising architectures of large-scale (hybrid) quantum networks.

Cicada feast and food links: Grey-headed flying fox preys on black prince in south-East Australia

Cicada mass emergence offers a plentiful and energy-rich food source for a variety of predators, mainly birds and spiders. Megabats (Pteropodidae) mostly feed on nectar and fruits, but occasionally prey on insects such as sap-sucking cicadas and fruit-eating beetles. We observed and documented with photographs the behavioural repertoire of the Grey-headed Flying Fox Pteropus poliocephalus while hunting and consuming the Black Prince cicada Psaltoda plaga in Sydney, New South Wales, Australia. The bats used three main tactics while hunting the cicadas: a) flushing and/or catching cicadas on tree foliage while clambering over branches or landing on the foliage, b) lunging from a perch after spotting a resting cicada, and c) pursuing cicadas on the wing. Upon securing a cicada the bats flew off and landed on a feeding perch, where they chewed the prey and spat the remains as a pellet below this perch. On the ground, the pellets were usually sought by large ants that tore off pieces from these remains, the ants transporting them to the nest. Small ants aggregated on the pellets probably to seek the remaining sap, after which they left the pellets. The above described events showed three main food links: a) cicadas feeding on plant sap, b) bats preying on cicadas and spitting the remains as pellets, and c) ants feeding on bat pellets. The links illustrate a food chain that include plants, cicadas, bats, and ants. Additional food links we observed were: 1) cicadas feeding on different plants, 2) cicadas preyed on by diurnal animals, 3) dead cicadas consumed by ants, 4) dead bats consumed by birds, and 5) nocturnal raptorial bird that may prey on bats. This report seems the first to mention food links within a megabat-insect trophic interaction.

Network wormhole attacks without a traditional wormhole

A prudent attacker tries to maximize profits during an attack, taking into account the investment cost for carrying out the attack; a cost which always exists. This includes the effort of information gathering, the energy and work needed to develop the attack, the risk of being exposed etc. The wormhole attack, in which a non-existent path is augmented to the network coaxing naive nodes to route traffic through the attackers, is accepted as one of the most destructive attacks in ad-hoc networks (e.g. manets, iot, wsn, uavs etc.). This research proposes a method to maximize the profit of the attack and challenges the axiomatic assumption of the wormhole attack protocol. We show that up to a specific point, there is a simpler alternative to the attack that does not require the creation of an additional fictitious link; yet, achieves optimal attack coverage. Simulating multiple network node/edge combinations in ns3, demonstrates how the benefit of every additional dedicated wormhole link is actually small and diminishes as link density increases. Our alternative, based on centrality measures, decreases the chance of being detected by ids/ips as no active topology manipulation is taking place.

Possibilities of expanding the field of application of torsional vibrations of speed

A new design of the spindle drive with torsional vibrations is considered, which makes it possible to implement additional kinematic links. Keywords: torsional vibrations, vibration drive, spindle, kinematic link. galia712@yandex.ru, gen_y@mail.ru

Communication-Free Voltage-Regulation and Current-Sharing for DC Microgrids: An Intelligent Edge Control

Though voltage-regulation and current-sharing of distributed generations (DGs) in dc-microgrids have been widely studied, additional communication links or independent modulation circuit should be added to achieve information transmission. To accomplish precise current-sharing/voltage-regulation without additional communication devices, this article proposes a communication-free intelligent edge control regarding voltage and current for dc-microgrids. First, the power-information dual modulation (PIDM) is designed to achieve information exchange among DGs and eliminate additional communication devices. Second, the cooperative control problem with two coupled targets, i.e., accurate voltage-regulation and current-sharing, is converted into a matter of optimal control. Therefore, the voltage-regulation and current-sharing could be solved concurrently. In addition, the control objective function of each DG is switched to provide the optimal controller and minimize the voltage/current control deviation, which is further switched to solve the Hamilton–Jacobi–Bellman (HJB) function. In order to solve this HJB function, which is difficult to obtain analytical solution, an intelligent edge control strategy with PIDM is proposed to solve the HJB function. Therefore, the precise voltage-regulation and current-sharing can be accomplished. Finally, the proposed control approach is verified through simulation results.

Joint Optimization of Phase Shift Matrices and Trajectory for AF Relay-Based Cooperation Communication With RIS-Enabled UAV System

In the complicated or hard-to-reach communication areas, sometimes much higher average achievable rate (AAR) or wider coverage is in urgent and temporary need. To address this challenge, this article proposes a novel amplify-and-forward (AF) relay-based cooperation communication scheme with reconfigurable intelligent surface (RIS)-enabled unmanned aerial vehicle (UAV) enhancing. The UAV acts as a moving RIS in the sky, which provides additional links to enhance the performance of the AF relay-based cooperation on the ground. Aiming to maximize the AAR of the proposed scheme, we jointly optimize the trajectory of UAV and the phase shift matrices of RIS over total time frames. At first, we decompose the original intractable problem into two subproblems of the phase shift matrices optimization and trajectory optimization. Subsequently, the optimal phase shift matrices are achieved by aligning the phases of received signals. Since the trajectory optimization subproblem is still complicated and nonconvex, we apply the successive convex approximation (SCA) method to reformulate it into a convex problem and further solve it by iterative method. Simulation results demonstrate the superiorities of the proposed scheme as compared with the benchmark schemes and also reveal the effects of various factors on its performance.

Research on improving robustness strategy of grid cyber physical system considering spatial information

Adding additional links can be recognized as an effective way to improve the robustness of grid cyber physical system (GCPS) against cascading failures. However, for a typical large-scale and across-regional GCPS, previous studies mainly focus on the network topology without considering the components/nodes spatial information. Therefore, to improve the robustness of GCPS without changing the existing connections, five different link addition strategies, considering spatial information and construction cost constraints, are proposed. Firstly, a spatial GCPS model is established, which consists of the spatial power system and the spatial information system with hierarchical structures. Among them, the spatial information system consists of the access layer (AL), the backbone layer (BL) and the core layer (CL) and its network nodes are divided into different layers according to their functions. Secondly, based on the spatial information system layer nodes functions and the spatial power system nodes attributions, five link addition strategies, AL-AL, AL-BL, AL-CL, Generators-CL (G-CL) and Loads-CL (L-CL), are investigated under two constraint scenarios. Thirdly, to verify our proposed five link addition strategies have better improvement effects, we compare them with the two existing excellent strategies, including low degree link addition strategy (LD) and random addition link addition strategy (Random). Finally, the statistical test results on the real 39-node power system and the IEEE 118 bus system show that our proposed link addition strategies not only effectively improve the robustness of GCPS, but also have better effects than LD and Random. More specifically, no matter whether GCPS suffered severe or slight attacks, the AL-BL always performs better when either fixed number constraint scenario or fixed length constraint scenario, and the improvement effects of AL-AL, AL-CL, G-CL and L-CL are exhibited as descending orders, respectively. These findings can help maintainers to improve the robustness of GCPS before attacks.

The Role of Undecenoic Acid on the Preparation of Decorated MCM-41/Polyethylene Hybrids by In Situ Polymerization: Catalytic Aspects and Properties of the Resultant Materials

Functionalized polyethylene-based nanocomposites were prepared by in situ polymerization of ethylene with modified or neat MCM-41 nanoparticles (NMCM-41). Two different synthetic approaches were investigated to improve the compatibility between the hydrophobic HDPE matrix and the hydrophilic NMCM-41: (i) incorporation of UA into the polymeric matrix by copolymerization with ethylene, promoted by the zirconocene catalyst under homogeneous conditions, in the presence of pristine NMCM-41; (ii) use of undecenoic acid (UA) as an interfacial agent to obtain decorated NMCM-41 to be used as nanofiller for the in situ ethylene polymerization, catalyzed by Cp2ZrCl2/MAO under supported conditions. The strong polar character of the carboxylic group is expected to either increase the hydrophilicity of the HDPE chains (strategy i) or interact with the NMCM-41 surface and provide an additional link to the polymeric chains via copolymerization of the vinyl group under supported conditions (strategy ii). Although metallocene catalysts have been shown to copolymerize olefins with functional monomers, the presence of oxygen-containing compounds in the reaction media strongly affects the polymerization activity as a result of the interaction of functional groups with the electrophilic active center of the catalyst. Thus, UA was pre-contacted with tri(isobutyl)aluminum (TIBA) prior to its use in the polymerization to reduce the deactivating character of the carboxylic acid groups towards the zirconocene catalyst. The influence of the UA presence on the polymerization behavior of the protection step is discussed, and the polymerization activities observed for the different approaches are compared. In addition, the thermal behavior and structural details of the resulting materials have been characterized. The impact of using neat or functionalized NMCM-41 on the final dispersion within the polymeric matrix is also analyzed, which is correlated with the mechanical performance exhibited by these HDPE_UA_NMCM-41 nanocomposites.