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2017-12-04
Sattar, N. S., Adnan, M. A., Kali, M. B..  2017.  Secured aerial photography using Homomorphic Encryption. 2017 International Conference on Networking, Systems and Security (NSysS). :107–114.

Aerial photography is fast becoming essential in scientific research that requires multi-agent system in several perspective and we proposed a secured system using one of the well-known public key cryptosystem namely NTRU that is somewhat homomorphic in nature. Here we processed images of aerial photography that were captured by multi-agents. The agents encrypt the images and upload those in the cloud server that is untrusted. Cloud computing is a buzzword in modern era and public cloud is being used by people everywhere for its shared, on-demand nature. Cloud Environment faces a lot of security and privacy issues that needs to be solved. This paper focuses on how to use cloud so effectively that there remains no possibility of data or computation breaches from the cloud server itself as it is prone to the attack of treachery in different ways. The cloud server computes on the encrypted data without knowing the contents of the images. After concatenation, encrypted result is delivered to the concerned authority where it is decrypted retaining its originality. We set up our experiment in Amazon EC2 cloud server where several instances were the agents and an instance acted as the server. We varied several parameters so that we could minimize encryption time. After experimentation we produced our desired result within feasible time sustaining the image quality. This work ensures data security in public cloud that was our main concern.

Thayananthan, V., Abdulkader, O., Jambi, K., Bamahdi, A. M..  2017.  Analysis of Cybersecurity Based on Li-Fi in Green Data Storage Environments. 2017 IEEE 4th International Conference on Cyber Security and Cloud Computing (CSCloud). :327–332.

Industrial networking has many issues based on the type of industries, data storage, data centers, and cloud computing, etc. Green data storage improves the scientific, commercial and industrial profile of the networking. Future industries are looking for cybersecurity solution with the low-cost resources in which the energy serving is the main problem in the industrial networking. To improve these problems, green data storage will be the priority because data centers and cloud computing deals with the data storage. In this analysis, we have decided to use solar energy source and different light rays as methodologies include a prism and the Li-Fi techniques. In this approach, light rays sent through the prism which allows us to transmit the data with different frequencies. This approach provides green energy and maximum protection within the data center. As a result, we have illustrated that cloud services within the green data center in industrial networking will achieve better protection with the low-cost energy through this analysis. Finally, we have to conclude that Li-Fi enhances the use of green energy and protection which are advantages to current and future industrial networking.

Al-Shomrani, A., Fathy, F., Jambi, K..  2017.  Policy enforcement for big data security. 2017 2nd International Conference on Anti-Cyber Crimes (ICACC). :70–74.

Security and privacy of big data becomes challenging as data grows and more accessible by more and more clients. Large-scale data storage is becoming a necessity for healthcare, business segments, government departments, scientific endeavors and individuals. Our research will focus on the privacy, security and how we can make sure that big data is secured. Managing security policy is a challenge that our framework will handle for big data. Privacy policy needs to be integrated, flexible, context-aware and customizable. We will build a framework to receive data from customer and then analyze data received, extract privacy policy and then identify the sensitive data. In this paper we will present the techniques for privacy policy which will be created to be used in our framework.

Rodrigues, P., Sreedharan, S., Basha, S. A., Mahesh, P. S..  2017.  Security threat identification using energy points. 2017 2nd International Conference on Anti-Cyber Crimes (ICACC). :52–54.

This research paper identifies security issues; especially energy based security attacks and enhances security of the system. It is very essential to consider Security of the system to be developed in the initial Phases of the software Cycle of Software Development (SDLC) as many billions of bucks are drained owing to security flaws in software caused due to improper or no security process. Security breaches that occur on software system are in umpteen numbers. Scientific Literature propose many solutions to overcome security issues, all security mechanisms are reactive in nature. In this paper new security solution is proposed that is proactive in nature especially for energy based denial of service attacks which is frequent in the recent past. Proposed solution is based on energy consumption by system known as energy points.

Athinaiou, M..  2017.  Cyber security risk management for health-based critical infrastructures. 2017 11th International Conference on Research Challenges in Information Science (RCIS). :402–407.

This brief paper reports on an early stage ongoing PhD project in the field of cyber-physical security in health care critical infrastructures. The research overall aims to develop a methodology that will increase the ability of secure recovery of health critical infrastructures. This ambitious or reckless attempt, as it is currently at an early stage, in this paper, tries to answer why cyber-physical security for health care infrastructures is important and of scientific interest. An initial PhD project methodology and expected outcomes are also discussed. The report concludes with challenges that emerge and possible future directions.

Mayer, N., Feltus, C..  2017.  Evaluation of the risk and security overlay of archimate to model information system security risks. 2017 IEEE 21st International Enterprise Distributed Object Computing Workshop (EDOCW). :106–116.

We evaluated the support proposed by the RSO to represent graphically our EAM-ISSRM (Enterprise Architecture Management - Information System Security Risk Management) integrated model. The evaluation of the RSO visual notation has been done at two different levels: completeness with regards to the EAM-ISSRM integrated model (Section III) and cognitive effectiveness, relying on the nine principles established by D. Moody ["The 'Physics' of Notations: Toward a Scientific Basis for Constructing Visual Notations in Software Engineering," IEEE Trans. Softw. Eng., vol. 35, no. 6, pp. 756-779, Nov. 2009] (Section IV). Regarding completeness, the coverage of the EAMISSRM integrated model by the RSO is complete apart from 'Event'. As discussed in Section III, this lack is negligible and we can consider the RSO as an appropriate notation to support the EAM-ISSRM integrated model from a completeness point of view. Regarding cognitive effectiveness, many gaps have been identified with regards to the nine principle established by Moody. Although no quantitative analysis has been performed to objectify this conclusion, the RSO can decently not be considered as an appropriate notation from a cognitive effectiveness point of view and there is room to propose a notation better on this aspect. This paper is focused on assessing the RSO without suggesting improvements based on the conclusions drawn. As a consequence, our objective for future work is to propose a more cognitive effective visual notation for the EAM-ISSRM integrated model. The approach currently considered is to operationalize Moody's principles into concrete metrics and requirements, taking into account the needs and profile of the target group of our notation (information security risk managers) through personas development and user experience map. With such an approach, we will be able to make decisions on the necessary trade-offs about our visual syntax, taking care of a specific context. We also aim at valida- ing our proposal(s) with the help of tools and approaches extracted from cognitive psychology research applied to HCI domain (e.g., eye tracking, heuristic evaluation, user experience evaluation…).

Lier, B. van.  2017.  The industrial internet of things and cyber security: An ecological and systemic perspective on security in digital industrial ecosystems. 2017 21st International Conference on System Theory, Control and Computing (ICSTCC). :641–647.

All over the world, objects are increasingly connected in networks such as the Industrial Internet of Things. Interconnections, intercommunications and interactions are driving the development of an entirely new whole in the form of the Industrial Internet of Things. Communication and interaction are the norm both for separate components, such as cyber-physical systems, and for the functioning of the system as a whole. This new whole can be likened to a natural ecosystem where the process of homeostasis ensures the stability and security of the whole. Components of such an industrial ecosystem, or even an industrial ecosystem as a whole, are increasingly targeted by cyber attacks. Such attacks not only threaten the functioning of one or multiple components, they also constitute a threat to the functioning of the new whole. General systems theory can offer a scientific framework for the development of measures to improve the security and stability of both separate components and the new whole.

Hwang, T..  2017.  NSF GENI cloud enabled architecture for distributed scientific computing. 2017 IEEE Aerospace Conference. :1–8.

GENI (Global Environment for Network Innovations) is a National Science Foundation (NSF) funded program which provides a virtual laboratory for networking and distributed systems research and education. It is well suited for exploring networks at a scale, thereby promoting innovations in network science, security, services and applications. GENI allows researchers obtain compute resources from locations around the United States, connect compute resources using 100G Internet2 L2 service, install custom software or even custom operating systems on these compute resources, control how network switches in their experiment handle traffic flows, and run their own L3 and above protocols. GENI architecture incorporates cloud federation. With the federation, cloud resources can be federated and/or community of clouds can be formed. The heart of federation is user identity and an ability to “advertise” cloud resources into community including compute, storage, and networking. GENI administrators can carve out what resources are available to the community and hence a portion of GENI resources are reserved for internal consumption. GENI architecture also provides “stitching” of compute and storage resources researchers request. This provides L2 network domain over Internet2's 100G network. And researchers can run their Software Defined Networking (SDN) controllers on the provisioned L2 network domain for a complete control of networking traffic. This capability is useful for large science data transfer (bypassing security devices for high throughput). Renaissance Computing Institute (RENCI), a research institute in the state of North Carolina, has developed ORCA (Open Resource Control Architecture), a GENI control framework. ORCA is a distributed resource orchestration system to serve science experiments. ORCA provides compute resources as virtual machines and as well as baremetals. ORCA based GENI ra- k was designed to serve both High Throughput Computing (HTC) and High Performance Computing (HPC) type of computes. Although, GENI is primarily used in various universities and research entities today, GENI architecture can be leveraged in the commercial, aerospace and government settings. This paper will go over the architecture of GENI and discuss the GENI architecture for scientific computing experiments.

Johnston, B., Lee, B., Angove, L., Rendell, A..  2017.  Embedded Accelerators for Scientific High-Performance Computing: An Energy Study of OpenCL Gaussian Elimination Workloads. 2017 46th International Conference on Parallel Processing Workshops (ICPPW). :59–68.

Energy efficient High-Performance Computing (HPC) is becoming increasingly important. Recent ventures into this space have introduced an unlikely candidate to achieve exascale scientific computing hardware with a small energy footprint. ARM processors and embedded GPU accelerators originally developed for energy efficiency in mobile devices, where battery life is critical, are being repurposed and deployed in the next generation of supercomputers. Unfortunately, the performance of executing scientific workloads on many of these devices is largely unknown, yet the bulk of computation required in high-performance supercomputers is scientific. We present an analysis of one such scientific code, in the form of Gaussian Elimination, and evaluate both execution time and energy used on a range of embedded accelerator SoCs. These include three ARM CPUs and two mobile GPUs. Understanding how these low power devices perform on scientific workloads will be critical in the selection of appropriate hardware for these supercomputers, for how can we estimate the performance of tens of thousands of these chips if the performance of one is largely unknown?

Farinholt, B., Rezaeirad, M., Pearce, P., Dharmdasani, H., Yin, H., Blond, S. L., McCoy, D., Levchenko, K..  2017.  To Catch a Ratter: Monitoring the Behavior of Amateur DarkComet RAT Operators in the Wild. 2017 IEEE Symposium on Security and Privacy (SP). :770–787.

Remote Access Trojans (RATs) give remote attackers interactive control over a compromised machine. Unlike large-scale malware such as botnets, a RAT is controlled individually by a human operator interacting with the compromised machine remotely. The versatility of RATs makes them attractive to actors of all levels of sophistication: they've been used for espionage, information theft, voyeurism and extortion. Despite their increasing use, there are still major gaps in our understanding of RATs and their operators, including motives, intentions, procedures, and weak points where defenses might be most effective. In this work we study the use of DarkComet, a popular commercial RAT. We collected 19,109 samples of DarkComet malware found in the wild, and in the course of two, several-week-long experiments, ran as many samples as possible in our honeypot environment. By monitoring a sample's behavior in our system, we are able to reconstruct the sequence of operator actions, giving us a unique view into operator behavior. We report on the results of 2,747 interactive sessions captured in the course of the experiment. During these sessions operators frequently attempted to interact with victims via remote desktop, to capture video, audio, and keystrokes, and to exfiltrate files and credentials. To our knowledge, we are the first large-scale systematic study of RAT use.

Donno, M. De, Dragoni, N., Giaretta, A., Spognardi, A..  2017.  Analysis of DDoS-capable IoT malwares. 2017 Federated Conference on Computer Science and Information Systems (FedCSIS). :807–816.

The Internet of Things (IoT) revolution promises to make our lives easier by providing cheap and always connected smart embedded devices, which can interact on the Internet and create added values for human needs. But all that glitters is not gold. Indeed, the other side of the coin is that, from a security perspective, this IoT revolution represents a potential disaster. This plethora of IoT devices that flooded the market were very badly protected, thus an easy prey for several families of malwares that can enslave and incorporate them in very large botnets. This, eventually, brought back to the top Distributed Denial of Service (DDoS) attacks, making them more powerful and easier to achieve than ever. This paper aims at provide an up-to-date picture of DDoS attacks in the specific subject of the IoT, studying how these attacks work and considering the most common families in the IoT context, in terms of their nature and evolution through the years. It also explores the additional offensive capabilities that this arsenal of IoT malwares has available, to mine the security of Internet users and systems. We think that this up-to-date picture will be a valuable reference to the scientific community in order to take a first crucial step to tackle this urgent security issue.

Fraunholz, D., Zimmermann, M., Anton, S. D., Schneider, J., Schotten, H. Dieter.  2017.  Distributed and highly-scalable WAN network attack sensing and sophisticated analysing framework based on Honeypot technology. 2017 7th International Conference on Cloud Computing, Data Science Engineering - Confluence. :416–421.

Recently, the increase of interconnectivity has led to a rising amount of IoT enabled devices in botnets. Such botnets are currently used for large scale DDoS attacks. To keep track with these malicious activities, Honeypots have proven to be a vital tool. We developed and set up a distributed and highly-scalable WAN Honeypot with an attached backend infrastructure for sophisticated processing of the gathered data. For the processed data to be understandable we designed a graphical frontend that displays all relevant information that has been obtained from the data. We group attacks originating in a short period of time in one source as sessions. This enriches the data and enables a more in-depth analysis. We produced common statistics like usernames, passwords, username/password combinations, password lengths, originating country and more. From the information gathered, we were able to identify common dictionaries used for brute-force login attacks and other more sophisticated statistics like login attempts per session and attack efficiency.

Boudguiga, A., Bouzerna, N., Granboulan, L., Olivereau, A., Quesnel, F., Roger, A., Sirdey, R..  2017.  Towards Better Availability and Accountability for IoT Updates by Means of a Blockchain. 2017 IEEE European Symposium on Security and Privacy Workshops (EuroS PW). :50–58.

Building the Internet of Things requires deploying a huge number of objects with full or limited connectivity to the Internet. Given that these objects are exposed to attackers and generally not secured-by-design, it is essential to be able to update them, to patch their vulnerabilities and to prevent hackers from enrolling them into botnets. Ideally, the update infrastructure should implement the CIA triad properties, i.e., confidentiality, integrity and availability. In this work, we investigate how the use of a blockchain infrastructure can meet these requirements, with a focus on availability. In addition, we propose a peer-to-peer mechanism, to spread updates between objects that have limited access to the Internet. Finally, we give an overview of our ongoing prototype implementation.

Joshi, H. P., Bennison, M., Dutta, R..  2017.  Collaborative botnet detection with partial communication graph information. 2017 IEEE 38th Sarnoff Symposium. :1–6.

Botnets have long been used for malicious purposes with huge economic costs to the society. With the proliferation of cheap but non-secure Internet-of-Things (IoT) devices generating large amounts of data, the potential for damage from botnets has increased manifold. There are several approaches to detect bots or botnets, though many traditional techniques are becoming less effective as botnets with centralized command & control structure are being replaced by peer-to-peer (P2P) botnets which are harder to detect. Several algorithms have been proposed in literature that use graph analysis or machine learning techniques to detect the overlay structure of P2P networks in communication graphs. Many of these algorithms however, depend on the availability of a universal communication graph or a communication graph aggregated from several ISPs, which is not likely to be available in reality. In real world deployments, significant gaps in communication graphs are expected and any solution proposed should be able to work with partial information. In this paper, we analyze the effectiveness of some community detection algorithms in detecting P2P botnets, especially with partial information. We show that the approach can work with only about half of the nodes reporting their communication graphs, with only small increase in detection errors.

Alejandre, F. V., Cortés, N. C., Anaya, E. A..  2017.  Feature selection to detect botnets using machine learning algorithms. 2017 International Conference on Electronics, Communications and Computers (CONIELECOMP). :1–7.

In this paper, a novel method to do feature selection to detect botnets at their phase of Command and Control (C&C) is presented. A major problem is that researchers have proposed features based on their expertise, but there is no a method to evaluate these features since some of these features could get a lower detection rate than other. To this aim, we find the feature set based on connections of botnets at their phase of C&C, that maximizes the detection rate of these botnets. A Genetic Algorithm (GA) was used to select the set of features that gives the highest detection rate. We used the machine learning algorithm C4.5, this algorithm did the classification between connections belonging or not to a botnet. The datasets used in this paper were extracted from the repositories ISOT and ISCX. Some tests were done to get the best parameters in a GA and the algorithm C4.5. We also performed experiments in order to obtain the best set of features for each botnet analyzed (specific), and for each type of botnet (general) too. The results are shown at the end of the paper, in which a considerable reduction of features and a higher detection rate than the related work presented were obtained.

Gardner, M. T., Beard, C., Medhi, D..  2017.  Using SEIRS Epidemic Models for IoT Botnets Attacks. DRCN 2017 - Design of Reliable Communication Networks; 13th International Conference. :1–8.

The spread of Internet of Things (IoT) botnets like those utilizing the Mirai malware were successful enough to power some of the most powerful DDoS attacks that have been seen thus far on the Internet. Two such attacks occurred on October 21, 2016 and September 20, 2016. Since there are an estimated three billion IoT devices currently connected to the Internet, these attacks highlight the need to understand the spread of IoT worms like Mirai and the vulnerability that they create for the Internet. In this work, we describe the spread of IoT worms using a proposed model known as the IoT Botnet with Attack Information (IoT-BAI), which utilizes a variation of the Susceptible-Exposed-Infected-Recovered-Susceptible (SEIRS) epidemic model [14]. The IoT-BAI model has shown that it may be possible to mitigate the frequency of IoT botnet attacks with improved user information which may positively affect user behavior. Additionally, the IoT-BAI model has shown that increased vulnerability to attack can be caused by new hosts entering the IoT population on a daily basis. Models like IoT-BAI could be used to predict user behavior after significant events in the network like a significant botnet attack.

Hongyo, K., Kimura, T., Kudo, T., Inoue, Y., Hirata, K..  2017.  Modeling of countermeasure against self-evolving botnets. 2017 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW). :227–228.

Machine learning has been widely used and achieved considerable results in various research areas. On the other hand, machine learning becomes a big threat when malicious attackers make use it for the wrong purpose. As such a threat, self-evolving botnets have been considered in the past. The self-evolving botnets autonomously predict vulnerabilities by implementing machine learning with computing resources of zombie computers. Furthermore, they evolve based on the vulnerability, and thus have high infectivity. In this paper, we consider several models of Markov chains to counter the spreading of the self-evolving botnets. Through simulation experiments, this paper shows the behaviors of these models.

Costa, V. G. T. da, Barbon, S., Miani, R. S., Rodrigues, J. J. P. C., Zarpelão, B. B..  2017.  Detecting mobile botnets through machine learning and system calls analysis. 2017 IEEE International Conference on Communications (ICC). :1–6.

Botnets have been a serious threat to the Internet security. With the constant sophistication and the resilience of them, a new trend has emerged, shifting botnets from the traditional desktop to the mobile environment. As in the desktop domain, detecting mobile botnets is essential to minimize the threat that they impose. Along the diverse set of strategies applied to detect these botnets, the ones that show the best and most generalized results involve discovering patterns in their anomalous behavior. In the mobile botnet field, one way to detect these patterns is by analyzing the operation parameters of this kind of applications. In this paper, we present an anomaly-based and host-based approach to detect mobile botnets. The proposed approach uses machine learning algorithms to identify anomalous behaviors in statistical features extracted from system calls. Using a self-generated dataset containing 13 families of mobile botnets and legitimate applications, we were able to test the performance of our approach in a close-to-reality scenario. The proposed approach achieved great results, including low false positive rates and high true detection rates.

Zhuang, D., Chang, J. M..  2017.  PeerHunter: Detecting peer-to-peer botnets through community behavior analysis. 2017 IEEE Conference on Dependable and Secure Computing. :493–500.

Peer-to-peer (P2P) botnets have become one of the major threats in network security for serving as the infrastructure that responsible for various of cyber-crimes. Though a few existing work claimed to detect traditional botnets effectively, the problem of detecting P2P botnets involves more challenges. In this paper, we present PeerHunter, a community behavior analysis based method, which is capable of detecting botnets that communicate via a P2P structure. PeerHunter starts from a P2P hosts detection component. Then, it uses mutual contacts as the main feature to cluster bots into communities. Finally, it uses community behavior analysis to detect potential botnet communities and further identify bot candidates. Through extensive experiments with real and simulated network traces, PeerHunter can achieve very high detection rate and low false positives.

Ferraris, L., Franchini, F., Pošković, E..  2016.  Hybrid magnetic composite (HMC) materials for sensor applications. 2016 IEEE Sensors Applications Symposium (SAS). :1–6.

Several applications adopt electromagnetic sensors, that base their principle on the presence of magnets realized with specific magnetic materials that show a rather high remanence, but low coercivity. This work concerns the production, analysis and characterization of hybrid composite materials, with the use of metal powders, which aim to reach those specific properties. In order to obtain the best coercivity and remanence characteristics various "recipes" have been used with different percentages of soft and hard magnetic materials, bonded together by a plastic binder. The goal was to find out the interdependence between the magnetic powder composition and the characteristics of the final material. Soft magnetic material (special Fe powder) has been used to obtain a low coercivity value, while hard materials were primarily used for maintaining a good induction remanence; by increasing the soft proportion a higher magnetic permeability has been also obtained. All the selected materials have been characterized and then tested; in order to verify the validity of the proposed materials two practical tests have been performed. Special magnets have been realized for a comparison with original ones (AlNiCo and ferrite) for two experimental cases: the first is consisting in an encoder realized through a toothed wheel, the second regards the special system used for the electric guitars.

Chen, Zhiwei, Bai, Baodong, Chen, DeZhi, Chai, Wenping.  2016.  Design of distribution devices for smart grid based on nanocomposite magnetic material. 2016 IEEE 8th International Power Electronics and Motion Control Conference (IPEMC-ECCE Asia). :3546–3553.

This paper design three distribution devices for the strong and smart grid, respectively are novel transformer with function of dc bias restraining, energy-saving contactor and controllable reactor with adjustable intrinsic magnetic state based on nanocomposite magnetic material core. The magnetic performance of this material was analyzed and the relationship between the remanence and coercivity was determined. The magnetization and demagnetization circuit for the nanocomposite core has been designed based on three-phase rectification circuit combined with a capacitor charging circuit. The remanence of the nanocomposite core can neutralize the dc bias flux occurred in transformer main core, can pull in the movable core of the contactor instead of the traditional fixed core and adjust the saturation degree of the reactor core. The electromagnetic design of the three distribution devices was conducted and the simulation, experiment results verify correctness of the design which provides intelligent and energy-saving power equipment for the smart power grids safe operation.

Guerra, Y., Gomes, J. L., Peña-Garcia, R., Delgado, A., Farias, B. V. M., Fuentes, G. P., Gonçalves, L. A. P., Padrón-Hernández, E..  2016.  Micromagnetic Simulation in Hexagonal Arrays of Nanosized Hollow Nickel Spheres. IEEE Transactions on Magnetics. 52:1–6.

Arrays of nanosized hollow spheres of Ni were studied using micromagnetic simulation by the Object Oriented Micromagnetic Framework. Before all the results, we will present an analysis of the properties for an individual hollow sphere in order to separate the real effects due to the array. The results in this paper are divided into three parts in order to analyze the magnetic behaviors in the static and dynamic regimes. The first part presents calculations for the magnetic field applied parallel to the plane of the array; specifically, we present the magnetization for equilibrium configurations. The obtained magnetization curves show that decreasing the thickness of the shell decreases the coercive field and it is difficult to obtain magnetic saturation. The values of the coercive field obtained in our work are of the same order as reported in experimental studies in the literature. The magnetic response in our study is dominated by the shape effects and we obtained high values for the reduced remanence, Mr/MS = 0.8. In the second part of this paper, we have changed the orientation of the magnetic field and calculated hysteresis curves to study the angular dependence of the coercive field and remanence. In thin shells, we have observed how the moments are oriented tangentially to the spherical surface. For the inversion of the magnetic moments we have observed the formation of vortex and onion modes. In the third part of this paper, we present an analysis for the process of magnetization reversal in the dynamic regime. The analysis showed that inversion occurs in the nonhomogeneous configuration. We could see that self-demagnetizing effects are predominant in the magnetic properties of the array. We could also observe that there are two contributions: one due to the shell as an independent object and the other due to the effects of the array.

Gonzalez, A. G., Millinger, J., Soulard, J..  2016.  Magnet losses in inverter-fed two-pole PM machines. 2016 XXII International Conference on Electrical Machines (ICEM). :1854–1860.

This article deals with the estimation of magnet losses in a permanent-magnet motor inserted in a nut-runner. This type of machine has interesting features such as being two-pole, slot-less and running at a high speed (30000 rpm). Two analytical models were chosen from the literature. A numerical estimation of the losses with 2D Finite Element Method was carried out. A detailed investigation of the effect of simulation settings (e.g., mesh size, time-step, remanence flux density in the magnet, superposition of the losses, etc.) was performed. Finally, calculation of losses with 3D-FEM were also run in order to compare the calculated losses with both analytical and 2D-FEM results. The estimation of the losses focuses on a range of frequencies between 10 and 100 kHz.

Insinga, A. R., Bjørk, R., Smith, A., Bahl, C. R. H..  2016.  Optimally Segmented Permanent Magnet Structures. IEEE Transactions on Magnetics. 52:1–6.

We present an optimization approach that can be employed to calculate the globally optimal segmentation of a 2-D magnetic system into uniformly magnetized pieces. For each segment, the algorithm calculates the optimal shape and the optimal direction of the remanent flux density vector, with respect to a linear objective functional. We illustrate the approach with results for magnet design problems from different areas, such as a permanent magnet electric motor, a beam-focusing quadrupole magnet for particle accelerators, and a rotary device for magnetic refrigeration.

Idayanti, N., Dedi, Nanang, T. K., Sudrajat, Septiani, A., Mulyadi, D., Irasari, P..  2016.  The implementation of hybrid bonded permanent magnet on permanent magnet generator for renewable energy power plants. 2016 International Seminar on Intelligent Technology and Its Applications (ISITIA). :557–560.

{This paper describes application of permanent magnet on permanent magnet generator (PMG) for renewable energy power plants. Permanent magnet used are bonded hybrid magnet that was a mixture of barium ferrite magnetic powders 50 wt % and NdFeB magnetic powders 50 wt % with 15 wt % of adhesive polymer as a binder. Preparation of bonded hybrid magnets by hot press method at a pressure of 2 tons and temperature of 200°C for 15 minutes. The magnetic properties obtained were remanence induction (Br) =1.54 kG, coercivity (Hc) = 1.290 kOe, product energy maximum (BHmax) = 0.28 MGOe, surface remanence induction (Br) = 1200 gauss