Biblio

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2019-01-16
Honggang, Zhao, Chen, Shi, Leyu, Zhai.  Submitted.  Design and Implementation of Lightweight 6LoWPAN Gateway Based on Contiki - IEEE Conference Publication.

6LoWPAN technology realizes the IPv6 packet transmission in the IEEE 802.15.4 based WSN. And 6LoWPAN is regarded as one of the ideal technologies to realize the interconnection between WSN and Internet, which is the key to build the IoT. Contiki is an open source and highly portable multitasking operating system, in which the 6LoWPAN has been implemented. In contiki, only several K Bytes of code and a few hundred bytes of memory are required to provide a multitasking environment and built-in TCP/IP support. This makes it especially suitable for memory constrained embedded platforms. In this paper, a lightweight 6LoWPAN gateway based on Contiki is designed and its designs of hardware and software are described. A complex experiment environment is presented, in which the gateway's capability of accessing the Internet is verified, and its performance about the average network delay and jitter are analyzed. The experimental results show that the gateway designed in this paper can not only realize the interconnection between 6LoWPAN networks and Internet, but also have good network adaptability and stability.

2017-03-20
Dormann, Will.  Submitted.  Google Authentication Risks on iOS. Proceedings of the 1st International Workshop on Mobile Development. :3–5.

The Google Identity Platform is a system that allows a user to sign in to applications and other services by using a Google account. Google Sign-In is one such method for providing one’s identity to the Google Identity Platform. Google Sign-In is available for Android applications and iOS applications, as well as for websites and other devices. Users of Google Sign-In find that it integrates well with the Android platform, but iOS users (iPhone, iPad, etc.) do not have the same experience. The user experience when logging in to a Google account on an iOS application can not only be more tedious than the Android experience, but it also conditions users to engage in behaviors that put the information in their Google accounts at risk.

2019-09-26
Kim, H., Hahn, C., Hur, J..  2019.  Analysis of Forward Private Searchable Encryption and Its Application to Multi-Client Settings. 2019 Eleventh International Conference on Ubiquitous and Future Networks (ICUFN). :529-531.
Searchable encryption (SE) supports privacy-preserving searches over encrypted data. Recent studies on SE have focused on improving efficiency of the schemes. However, it was shown that most of the previous SE schemes could reveal the client's queries even if they are encrypted, thereby leading to privacy violation. In order to solve the problem, several forward private SE schemes have been proposed in a single client environment. However, the previous forward private SE schemes have never been analyzed in multi-client settings. In this paper, we briefly review the previous forward private SE schemes. Then, we conduct a comparative analysis of them in terms of performance and forward privacy. Our analysis demonstrates the previous forward secure SE schemes highly depend on the file-counter. Lastly, we show that they are not scalable in multi-client settings due to the performance and security issue from the file-counter.
2019-08-05
Ahmad, F., Adnane, A., KURUGOLLU, F., Hussain, R..  2019.  A Comparative Analysis of Trust Models for Safety Applications in IoT-Enabled Vehicular Networks. 2019 Wireless Days (WD). :1-8.
Vehicular Ad-hoc NETwork (VANET) is a vital transportation technology that facilitates the vehicles to share sensitive information (such as steep-curve warnings and black ice on the road) with each other and with the surrounding infrastructure in real-time to avoid accidents and enable comfortable driving experience.To achieve these goals, VANET requires a secure environment for authentic, reliable and trusted information dissemination among the network entities. However, VANET is prone to different attacks resulting in the dissemination of compromised/false information among network nodes. One way to manage a secure and trusted network is to introduce trust among the vehicular nodes. To this end, various Trust Models (TMs) are developed for VANET and can be broadly categorized into three classes, Entity-oriented Trust Models (ETM), Data oriented Trust Models (DTM) and Hybrid Trust Models (HTM). These TMs evaluate trust based on the received information (data), the vehicle (entity) or both through different mechanisms. In this paper, we present a comparative study of the three TMs. Furthermore, we evaluate these TMs against the different trust, security and quality-of-service related benchmarks. Simulation results revealed that all these TMs have deficiencies in terms of end-to-end delays, event detection probabilities and false positive rates. This study can be used as a guideline for researchers to design new efficient and effective TMs for VANET.
2019-10-02
Zhang, Y., Eisele, S., Dubey, A., Laszka, A., Srivastava, A. K..  2019.  Cyber-Physical Simulation Platform for Security Assessment of Transactive Energy Systems. 2019 7th Workshop on Modeling and Simulation of Cyber-Physical Energy Systems (MSCPES). :1–6.
Transactive energy systems (TES) are emerging as a transformative solution for the problems that distribution system operators face due to an increase in the use of distributed energy resources and rapid growth in scalability of managing active distribution system (ADS). On the one hand, these changes pose a decentralized power system control problem, requiring strategic control to maintain reliability and resiliency for the community and for the utility. On the other hand, they require robust financial markets while allowing participation from diverse prosumers. To support the computing and flexibility requirements of TES while preserving privacy and security, distributed software platforms are required. In this paper, we enable the study and analysis of security concerns by developing Transactive Energy Security Simulation Testbed (TESST), a TES testbed for simulating various cyber attacks. In this work, the testbed is used for TES simulation with centralized clearing market, highlighting weaknesses in a centralized system. Additionally, we present a blockchain enabled decentralized market solution supported by distributed computing for TES, which on one hand can alleviate some of the problems that we identify, but on the other hand, may introduce newer issues. Future study of these differing paradigms is necessary and will continue as we develop our security simulation testbed.
2019-09-23
Zheng, N., Alawini, A., Ives, Z. G..  2019.  Fine-Grained Provenance for Matching ETL. 2019 IEEE 35th International Conference on Data Engineering (ICDE). :184–195.
Data provenance tools capture the steps used to produce analyses. However, scientists must choose among workflow provenance systems, which allow arbitrary code but only track provenance at the granularity of files; provenance APIs, which provide tuple-level provenance, but incur overhead in all computations; and database provenance tools, which track tuple-level provenance through relational operators and support optimization, but support a limited subset of data science tasks. None of these solutions are well suited for tracing errors introduced during common ETL, record alignment, and matching tasks - for data types such as strings, images, etc. Scientists need new capabilities to identify the sources of errors, find why different code versions produce different results, and identify which parameter values affect output. We propose PROVision, a provenance-driven troubleshooting tool that supports ETL and matching computations and traces extraction of content within data objects. PROVision extends database-style provenance techniques to capture equivalences, support optimizations, and enable selective evaluation. We formalize our extensions, implement them in the PROVision system, and validate their effectiveness and scalability for common ETL and matching tasks.
2019-09-09
Macwan, S., Lung, C..  2019.  Investigation of Moving Target Defense Technique to Prevent Poisoning Attacks in SDN. 2019 IEEE World Congress on Services (SERVICES). 2642-939X:178–183.
The motivation behind Software-Defined Networking (SDN) is to allow services and network capabilities to be managed through a central control point. Moving Target Defense (MTD) introduces a constantly changing environment in order to delay or prevent attacks on a system. For the effective use of MTD, SDN can be used to help confuse the attacker from gathering legitimate information about the network. This paper investigates how SDN can be used for some network based MTD techniques and evaluate the benefits of integrating techniques in SDN and MTD. In the experiment, network assets are kept hidden from inside and outside attackers. Furthermore, the SDN controller is programed to perform IP mutation to keep changing real IP addresses of the underlying hosts by assigning each host a virtual IP address at a configured mutation rate to prevent attackers from stealing the real IP addresses or using fake IP addresses. The paper demonstrates experimental evaluation of the MTD technique using the Ryu controller and mininet. The results show that the MTD technique can be easily integrated into the SDN environment to use virtual IP addresses for hosts to reduce the chance of poisoning attacks.
2019-01-21
Gao, J., Wang, J., Zhang, L., Yu, Q., Huang, Y., Shen, Y..  2019.  Magnetic Signature Analysis for Smart Security System Based on TMR Magnetic Sensor Array. IEEE Sensors Journal. :1–1.
This paper presents a novel low power security system based on magnetic anomaly detection by using Tunneling Magnetoresistance (TMR) magnetic sensors. In this work, a smart light has been developed, which consists of TMR sensors array, detection circuits, a micro-controller and a battery. Taking the advantage of low power consumption of TMR magnetic sensors, the smart light powered by Li-ion battery can work for several months. Power Spectrum Density of the obtained signal was analyzed to reject background noise and improve the signal to noise ratio effectively by 1.3 dB, which represented a 30% detection range improvement. Also, by sending the signals to PC, the magnetic fingerprints of the objects have been configured clearly. In addition, the quick scan measurement has been also performed to demonstrate that the system can discriminate the multiple objects with 30 cm separation. Since the whole system was compact and portable, it can be used for security check at office, meeting room or other private places without attracting any attention. Moreover, it is promising to integrate multiply such systems together to achieve a wireless security network in large-scale monitoring.
2019-10-14
Tymburibá, M., Sousa, H., Pereira, F..  2019.  Multilayer ROP Protection Via Microarchitectural Units Available in Commodity Hardware. 2019 49th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN). :315–327.
This paper presents a multilayer protection approach to guard programs against Return-Oriented Programming (ROP) attacks. Upper layers validate most of a program's control flow at a low computational cost; thus, not compromising runtime. Lower layers provide strong enforcement guarantees to handle more suspicious flows; thus, enhancing security. Our multilayer system combines techniques already described in the literature with verifications that we introduce in this paper. We argue that modern versions of x86 processors already provide the microarchitectural units necessary to implement our technique. We demonstrate the effectiveness of our multilayer protection on a extensive suite of benchmarks, which includes: SPEC CPU2006; the three most popular web browsers; 209 benchmarks distributed with LLVM and four well-known systems shown to be vulnerable to ROP exploits. Our experiments indicate that we can protect programs with almost no overhead in practice, allying the good performance of lightweight security techniques with the high dependability of heavyweight approaches.
2019-09-09
Almohaimeed, A., Asaduzzaman, A..  2019.  A Novel Moving Target Defense Technique to Secure Communication Links in Software-Defined Networks. 2019 Fifth Conference on Mobile and Secure Services (MobiSecServ). :1–4.
Software-defined networking (SDN) is a recently developed approach to computer networking that brings a centralized orientation to network control, thereby improving network architecture and management. However, as with any communication environment that involves message transmission among users, SDN is confronted by the ongoing challenge of protecting user privacy. In this “Work in Progress (WIP)” research, we propose an SDN security model that applies the moving target defense (MTD) technique to protect communication links from sensitive data leakages. MTD is a security solution aimed at increasing complexity and uncertainty for attackers by concealing sensitive information that may serve as a gateway from which to launch different types of attacks. The proposed MTD-based security model is intended to protect user identities contained in transmitted messages in a way that prevents network intruders from identifying the real identities of senders and receivers. According to the results from preliminary experiments, the proposed MTD model has potential to protect the identities contained in transmitted messages within communication links. This work will be extended to protect sensitive data if an attacker gets access to the network device.
2019-09-26
Li, S., Wang, F., Shi, T., Kuang, J..  2019.  Probably Secure Multi-User Multi-Keyword Searchable Encryption Scheme in Cloud Storage. 2019 IEEE 3rd Information Technology, Networking, Electronic and Automation Control Conference (ITNEC). :1368-1372.
Searchable encryption server protects privacal data of data owner from leaks. This paper analyzes the security of a multi-user searchable encryption scheme and points out that this scheme does not satisfy the invisibility of trapdoors. In order to improve the security of the original scheme, this paper proposes a probably secure multi-user multi-keyword searchable encryption scheme. New secheme not only ensures the confidentiality of the cipher text keyword, but also does not increase the encryption workload of the data owner when the new data user joins. In the random oracle model, based on the hard problem of decisional Diffie-Hellman, it is proved that the scheme has trapdoor indistinguishability. In the end, obtained by the simulation program to achieve a new computationally efficient communication at low cost.
2019-09-23
Aydin, Y., Ozkaynak, F..  2019.  A Provable Secure Image Encryption Schema Based on Fractional Order Chaotic Systems. 2019 23rd International Conference Electronics. :1–5.
In the literature, many chaotic systems have been used in the design of image encryption algorithms. In this study, an application of fractional order chaotic systems is investigated. The aim of the study is to improve the disadvantageous aspects of existing methods based on discrete and continuous time chaotic systems by utilizing the features of fractional order chaotic systems. The most important advantage of the study compared to the literature is that the proposed encryption algorithm is designed with a provable security approach. Analyses results have been shown that the proposed method can be used successfully in many information security applications.
Hunag, C., Yang, C., Weng, C., Chen, Y., Wang, S..  2019.  Secure Protocol for Identity-based Provable Data Possession in Cloud Storage. 2019 IEEE 4th International Conference on Computer and Communication Systems (ICCCS). :327–331.
Remote data possession is becoming an increasingly important issue in cloud storage. It enables users to verify if their outsourced data have remained intact while in cloud storage. The existing remote data audit (RDA) protocols were designed with the public key infrastructure (PKI) system. However, this incurs considerable costs when users need to frequently access data from the cloud service provider with PKI. This study proposes a protocol, called identity-based RDA (ID-RDA) that addresses this problem without the need for users’ certificates. This study outperforms existing RDA protocols in computation and communication.
2019-09-30
Liu, Y., Li, L., Gao, Q., Cao, J., Wang, R., Sun, Z..  2019.  Analytical Model of Torque-Prediction for a Novel Hybrid Rotor Permanent Magnet Machines. IEEE Access. 7:109528–109538.

This paper presents an analytical method for predicting the electromagnetic performance in permanent magnet (PM) machine with the spoke-type rotor (STR) and a proposed hybrid rotor structure (HRS), respectively. The key of this method is to combine magnetic field analysis model (MFAM) with the magnetic equivalent circuit model. The influence of the irregular PM shape is considered by the segmentation calculation. To obtain the boundary condition in the MFAM, respectively, two equivalent methods on the rotor side are proposed. In the STR, the average flux density of the rotor core outer-surface is calculated to solve the Laplace's equation with considering for the rotor core outer-surface eccentric. In the HRS, based on the Thevenin's theorem, the equivalent parameters of PM remanence BreB and thickness hpme are obtained as a given condition, which can be utilized to compute the air-gap flux density by conventional classic magnetic field analysis model of surface-mounted PMs with air-gap region. Finally, the proposed analytical models are verified by the finite element analysis (FEA) with comparisons of the air-gap flux density, flux linkage, back-EMF and electromagnetic torque, respectively. Furthermore, the performance that the machine with the proposed hybrid structure rotor can improve the torque density as explained.

2019-10-07
Agrawal, R., Stokes, J. W., Selvaraj, K., Marinescu, M..  2019.  Attention in Recurrent Neural Networks for Ransomware Detection. ICASSP 2019 - 2019 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). :3222–3226.

Ransomware, as a specialized form of malicious software, has recently emerged as a major threat in computer security. With an ability to lock out user access to their content, recent ransomware attacks have caused severe impact at an individual and organizational level. While research in malware detection can be adapted directly for ransomware, specific structural properties of ransomware can further improve the quality of detection. In this paper, we adapt the deep learning methods used in malware detection for detecting ransomware from emulation sequences. We present specialized recurrent neural networks for capturing local event patterns in ransomware sequences using the concept of attention mechanisms. We demonstrate the performance of enhanced LSTM models on a sequence dataset derived by the emulation of ransomware executables targeting the Windows environment.

2019-09-30
Xu, F., Peng, R., Zheng, T., Xu, X..  2019.  Development and Validation of Numerical Magnetic Force and Torque Model for Magnetically Levitated Actuator. IEEE Transactions on Magnetics. 55:1–9.

To decouple the multi-axis motion in the 6 degrees of freedom magnetically levitated actuators (MLAs), this paper introduces a numerical method to model the force and torque distribution. Taking advantage of the Gaussian quadrature, the concept of coil node is developed to simplify the Lorentz integral into the summation of the interaction between each magnetic node in the remanence region and each coil node in the coil region. Utilizing the coordinate transformation in the numerical method, the computation burden is independent of the position and the rotation angle of the moving part. Finally, the experimental results prove that the force and torque predicted by the numerical model are rigidly consistent with the measurement, and the force and torque in all directions are decoupled properly based on the numerical solution. Compared with the harmonic model, the numerical wrench model is more suitable for the MLAs undertaking both the translational and rotational displacements.

Hohlfeld, J., Czoschke, P., Asselin, P., Benakli, M..  2019.  Improving Our Understanding of Measured Jitter (in HAMR). IEEE Transactions on Magnetics. 55:1–11.

The understanding of measured jitter is improved in three ways. First, it is shown that the measured jitter is not only governed by written-in jitter and the reader resolution along the cross-track direction but by remanence noise in the vicinity of transitions and the down-track reader resolution as well. Second, a novel data analysis scheme is introduced that allows for an unambiguous separation of these two contributions. Third, based on data analyses involving the first two learnings and micro-magnetic simulations, we identify and explain the root causes for variations of jitter with write current (WC) (write field), WC overshoot amplitude (write-field rise time), and linear disk velocity measured for heat-assisted magnetic recording.

2019-05-20
Dey, H., Islam, R., Arif, H..  2019.  An Integrated Model To Make Cloud Authentication And Multi-Tenancy More Secure. 2019 International Conference on Robotics,Electrical and Signal Processing Techniques (ICREST). :502–506.

Cloud Computing is an important term of modern technology. The usefulness of Cloud is increasing day by day and simultaneously more and more security problems are arising as well. Two of the major threats of Cloud are improper authentication and multi-tenancy. According to the specialists both pros and cons belong to multi-tenancy. There are security protocols available but it is difficult to claim these protocols are perfect and ensure complete protection. The purpose of this paper is to propose an integrated model to ensure better Cloud security for Authentication and multi-tenancy. Multi-tenancy means sharing of resources and virtualization among clients. Since multi-tenancy allows multiple users to access same resources simultaneously, there is high probability of accessing confidential data without proper privileges. Our model includes Kerberos authentication protocol to enhance authentication security. During our research on Kerberos we have found some flaws in terms of encryption method which have been mentioned in couple of IEEE conference papers. Pondering about this complication we have elected Elliptic Curve Cryptography. On the other hand, to attenuate arose risks due to multi-tenancy we are proposing a Resource Allocation Manager Unit, a Control Database and Resource Allocation Map. This part of the model will perpetuate resource allocation for the users.

2019-08-12
Liu, Y., Yang, Y., Shi, A., Jigang, P., Haowei, L..  2019.  Intelligent monitoring of indoor surveillance video based on deep learning. 2019 21st International Conference on Advanced Communication Technology (ICACT). :648–653.

With the rapid development of information technology, video surveillance system has become a key part in the security and protection system of modern cities. Especially in prisons, surveillance cameras could be found almost everywhere. However, with the continuous expansion of the surveillance network, surveillance cameras not only bring convenience, but also produce a massive amount of monitoring data, which poses huge challenges to storage, analytics and retrieval. The smart monitoring system equipped with intelligent video analytics technology can monitor as well as pre-alarm abnormal events or behaviours, which is a hot research direction in the field of surveillance. This paper combines deep learning methods, using the state-of-the-art framework for instance segmentation, called Mask R-CNN, to train the fine-tuning network on our datasets, which can efficiently detect objects in a video image while simultaneously generating a high-quality segmentation mask for each instance. The experiment show that our network is simple to train and easy to generalize to other datasets, and the mask average precision is nearly up to 98.5% on our own datasets.

2019-10-02
Damghani, H., Hosseinian, H., Damghani, L..  2019.  Investigating Attacks to Improve Security and Privacy in RFID Systems Using the Security Bit Method. 2019 5th Conference on Knowledge Based Engineering and Innovation (KBEI). :833–838.

The RFID technology is now widely used and combined with everyday life. RFID Tag is a wireless device used to identify individuals and objects, in fact, it is a combination of the chip and antenna that sends the necessary information to an RFID Reader. On the other hand, an RFID Reader converts received radio waves into digital information and then provides facilities such as sending data to the computer and processing them. Radio frequency identification is a comprehensive processing technology that has led to a revolution in industry and medicine as an alternative to commercial barcodes. RFID Tag is used to tracking commodities and personal assets in the chain stores and even the human body and medical science. However, security and privacy problems have not yet been solved satisfactorily. There are many technical and economic challenges in this direction. In this paper, some of the latest technical research on privacy and security problems has been investigated in radio-frequency identification and security bit method, and it has been shown that in order to achieve this level of individual security, multiple technologies of RFID security development should combine with each other. These solutions should be cheap, efficient, reliable, flexible and long-term.

2019-09-11
Yin, Z., Dou, S., Bai, H., Hou, Y..  2019.  Light-Weighted Security Access Scheme of Broadband Power Line Communications for Multi-Source Information Collection. 2019 IEEE 3rd Information Technology, Networking, Electronic and Automation Control Conference (ITNEC). :1087–1090.

With the continuously development of smart meter-reading technologies for decades, remote information collection of electricity, water, gas and heat meters have been realized. Due to the difference of electrical interfaces and communication protocols among various types of meters, communication modes of meter terminals are not so compatible, it is difficult to realize communication optimization of electricity, water, gas and heat meters information collection services. In addition, with the development of power consumption information acquisition system, the number of acquisition terminals soars greatly and the data of terminal access is highly concurrent. Therefore, the risk of security access is increasing. This paper presents a light-weighted security access scheme of power line communication based on multi-source data acquisition of electricity, water, gas and heat meters, which separates multi-source data acquisition services and achieve services security isolation and channel security isolation. The communication reliability and security of the meter-reading service of "electricity, water, gas and heat" will be improved and the integrated meter service will be realized reliably.

2019-05-01
Vagin, V. V., Butakova, N. G..  2019.  Mathematical Modeling of Group Authentication Based on Isogeny of Elliptic Curves. 2019 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus). :1780–1785.

In this paper, we consider ways of organizing group authentication, as well as the features of constructing the isogeny of elliptic curves. The work includes the study of isogeny graphs and their application in postquantum systems. A hierarchical group authentication scheme has been developed using transformations based on the search for isogeny of elliptic curves.

2019-05-20
Goncharov, N. I., Goncharov, I. V., Parinov, P. A., Dushkin, A. V., Maximova, M. M..  2019.  Modeling of Information Processes for Modern Information System Security Assessment. 2019 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus). :1758-1763.

A new approach of a formalism of hybrid automatons has been proposed for the analysis of conflict processes between the information system and the information's security malefactor. An example of probability-based assessment on malefactor's victory has been given and the possibility to abstract from a specific type of probability density function for the residence time of parties to the conflict in their possible states. A model of the distribution of destructive informational influences in the information system to connect the process of spread of destructive information processes and the process of changing subjects' states of the information system has been proposed. An example of the destructive information processes spread analysis has been given.

2019-06-28
Hazari, S. S., Mahmoud, Q. H..  2019.  A Parallel Proof of Work to Improve Transaction Speed and Scalability in Blockchain Systems. 2019 IEEE 9th Annual Computing and Communication Workshop and Conference (CCWC). :0916-0921.

A blockchain is a distributed ledger forming a distributed consensus on a history of transactions, and is the underlying technology for the Bitcoin cryptocurrency. However, its applications are far beyond the financial sector. The transaction verification process for cryptocurrencies is much slower than traditional digital transaction systems. One approach to increase transaction speed and scalability is to identify a solution that offers faster Proof of Work. In this paper, we propose a method for accelerating the process of Proof of Work based on parallel mining rather than solo mining. The goal is to ensure that no more than two or more miners put the same effort into solving a specific block. The proposed method includes a process for selection of a manager, distribution of work and a reward system. This method has been implemented in a test environment that contains all the characteristics needed to perform Proof of Work for Bitcoin and has been tested, using a variety of case scenarios, by varying the difficulty level and number of validators. Preliminary results show improvement in the scalability of Proof of Work up to 34% compared to the current system.

2019-09-30
Davila, Y. G., Júnior, F. A. Revoredo, Peña-Garcia, R., Padrón-Hernández, E..  2019.  Peak in Angular Dependence of Coercivity in a Hexagonal Array of Permalloy Spherical Nanocaps. IEEE Magnetics Letters. 10:1–3.

Micromagnetic simulations of coercivity as a function of external magnetic field direction were performed for a hexagonal array of hemispherical Permalloy nanocaps. The analysis was based on hysteresis loops for arrangements of nanocaps of variable thickness (5 nm and 10 nm). The angular dependence of coercivity had a maximum at about 80° with respect to the arrangement plane. An increase in coercivity with nanocap thickness is related to the magnetization reversal mechanism, where the dipole energy of individual caps generates an effective intermediate axis, locking the magnetic moments. The coercivity has maximum values of 109 Oe for 5 nm and 156 Oe for 10 nm thickness. The remanence decreases monotonically with angle. This is associated with the influence of shape anisotropy, where the demagnetizing field in the plane of the array is much smaller than the demagnetizing field perpendicular to the plane.