WorldWideScience

Sample records for access control communications

  1. Modemless Multiple Access Communications over Powerlines for DC Microgrid Control

    OpenAIRE

    Angjelichinoski, Marko; Stefanovic, Cedomir; Popovski, Petar

    2016-01-01

    We present a communication solution tailored specifically for DC microgrids (MGs) that exploits: (i) the communication potential residing in power electronic converters interfacing distributed generators to powerlines and (ii) the multiple access nature of the communication channel presented by powerlines. The communication is achieved by modulating the parameters of the primary control loop implemented by the converters, fostering execution of the upper layer control applications. We present...

  2. Secure Communication and Access Control for Mobile Web Service Provisioning

    CERN Document Server

    Srirama, Satish Narayana

    2010-01-01

    It is now feasible to host basic web services on a smart phone due to the advances in wireless devices and mobile communication technologies. While the applications are quite welcoming, the ability to provide secure and reliable communication in the vulnerable and volatile mobile ad-hoc topologies is vastly becoming necessary. The paper mainly addresses the details and issues in providing secured communication and access control for the mobile web service provisioning domain. While the basic message-level security can be provided, providing proper access control mechanisms for the Mobile Host still poses a great challenge. This paper discusses details of secure communication and proposes the distributed semantics-based authorization mechanism.

  3. The effects of hands free communication devices on clinical communication: balancing communication access needs with user control.

    Science.gov (United States)

    Richardson, Joshua E; Richardson, Joshua Edwin; Ash, Joan S; Ash, Joan

    2008-11-06

    Hands Free Communication Device (HFCD) systems are a relatively new information and communication technology. HFCD systems enable clinicians to directly contact and communicate with one another using wearable, voice-controlled badges that are VoIP-based (voice-over IP) and are linked to one another over a wireless local area network (WLAN). This qualitative study utilized a grounded theory, multiple perspectives approach to understand how the use of HFCDs affected communication in the hospitals that implemented them. The study generated five themes revolving around HFCDs impact on communication. This paper specifically focuses on two of those themes: Communication Access and Control.

  4. Optimizing data access for wind farm control over hierarchical communication networks

    DEFF Research Database (Denmark)

    Madsen, Jacob Theilgaard; Findrik, Mislav; Madsen, Tatiana Kozlova

    2016-01-01

    and communication networks on the controller performance. We start by investigating the effects of a communication network that introduces delays in the information access for the central controller. The control performance as measured by accumulated fatigue is shown to be significantly impacted by communication....... This information quality metric is called mismatch probability, mmPr, and is used to express quantitatively the information accuracy in a given scenario. Lastly measurements of different communication technologies have been performed in order to carry out the analysis in a practically relevant scenario......In this paper we investigate a centralized wind farm controller which runs periodically. The controller attempts to reduce the damage a wind turbine sustains during operation by estimating fatigue based on the wind turbine state. The investigation focuses on the impact of information access...

  5. An internet of things example: classrooms access control over near field communication.

    Science.gov (United States)

    Palma, Daniel; Agudo, Juan Enrique; Sánchez, Héctor; Macías, Miguel Macías

    2014-04-21

    The Internet of Things is one of the ideas that has become increasingly relevant in recent years. It involves connecting things to the Internet in order to retrieve information from them at any time and from anywhere. In the Internet of Things, sensor networks that exchange information wirelessly via Wi-Fi, Bluetooth, Zigbee or RF are common. In this sense, our paper presents a way in which each classroom control is accessed through Near Field Communication (NFC) and the information is shared via radio frequency. These data are published on the Web and could easily be used for building applications from the data collected. As a result, our application collects information from the classroom to create a control classroom tool that displays access to and the status of all the classrooms graphically and also connects this data with social networks.

  6. An Internet of Things Example: Classrooms Access Control over Near Field Communication

    Directory of Open Access Journals (Sweden)

    Daniel Palma

    2014-04-01

    Full Text Available The Internet of Things is one of the ideas that has become increasingly relevant in recent years. It involves connecting things to the Internet in order to retrieve information from them at any time and from anywhere. In the Internet of Things, sensor networks that exchange information wirelessly via Wi-Fi, Bluetooth, Zigbee or RF are common. In this sense, our paper presents a way in which each classroom control is accessed through Near Field Communication (NFC and the information is shared via radio frequency. These data are published on the Web and could easily be used for building applications from the data collected. As a result, our application collects information from the classroom to create a control classroom tool that displays access to and the status of all the classrooms graphically and also connects this data with social networks.

  7. In-home Power Line Communication Media Access Control Protocol Based on Collision Resolution

    Institute of Scientific and Technical Information of China (English)

    WANG Bo; HUANG Pei-wei; ZHONG You-ping; QI Ying-hao

    2009-01-01

    Most existing media access control (MAC) protocols in power line communication (PLC) networks just discard the colliding data packets when collision occurs. The collision deteriorates throughput and delay performance of system under high traffic conditions. This article presents a novel media access scheme with fast collision resolution for in-home power line networks. It works by first recognizing the colliding stations through detecting the inserted unique ID sequence ahead of data packets, then the source nodes retransmitting their packets immediately after the collision slot. The proposed protocol maintains the benefits of ALOHA systems. It needs no scheduling overhead and is suitable for bursty sources, such as multimedia data packets. Computer simulations have demonstrated that this approach can achieve high throughput due to its ability of resolving collisions.

  8. Multiple Access Communications

    DEFF Research Database (Denmark)

    This book constitutes the proceedings of the 9th International Workshop on Multiple Access Communications, MACOM 2016, held in Aalborg, Denmark, in November 2016. The 10 full papers presented in this volume were carefully reviewed and selected from 12 submissions. They were organized in topical...

  9. Ontology Based Access Control

    Directory of Open Access Journals (Sweden)

    Özgü CAN

    2010-02-01

    Full Text Available As computer technologies become pervasive, the need for access control mechanisms grow. The purpose of an access control is to limit the operations that a computer system user can perform. Thus, access control ensures to prevent an activity which can lead to a security breach. For the success of Semantic Web, that allows machines to share and reuse the information by using formal semantics for machines to communicate with other machines, access control mechanisms are needed. Access control mechanism indicates certain constraints which must be achieved by the user before performing an operation to provide a secure Semantic Web. In this work, unlike traditional access control mechanisms, an "Ontology Based Access Control" mechanism has been developed by using Semantic Web based policies. In this mechanism, ontologies are used to model the access control knowledge and domain knowledge is used to create policy ontologies.

  10. Wireless Access Control with Smart Antenna for M2M Communications

    Science.gov (United States)

    Sakamoto, Hiroshi; Bandai, Masaki; Watanabe, Takashi

    Machine to machine (M2M) is a promising technology to achieve an ubiquitous environment by uniting machines and machines over the Internet. The network used for M2M consists of core network and access network. This paper discusses effective controls of the wireless access network for M2M. Among typical examples of the wireless access network for M2M is a wireless sensor network (WSN). WSN for M2M may require energy efficiency, high reliability and throughput. For these requirements, in this paper, we propose a scheme to build a hierarchical sensor network using smart antenna. The proposed scheme uses omni-directional antennas together with smart antennas. Since smart antennas can extend communications distance, the proposed scheme enables reduction of number of hops to reduce the traffic load on relay nodes. As a result, the energy consumption, data collection ratio and throughput can be improved. We implement the proposed scheme on a real testbed. The testbed uses UNAGI as smart antenna nodes and Mica Mote as sensor nodes. In addition to the fundamental evaluation on the testbed, we simulate large-scale sensor networks. The results show the effectiveness of the proposed hierarchical sensor network with smart antennas.

  11. A Brief Survey of Media Access Control, Data Link Layer, and Protocol Technologies for Lunar Surface Communications

    Science.gov (United States)

    Wallett, Thomas M.

    2009-01-01

    This paper surveys and describes some of the existing media access control and data link layer technologies for possible application in lunar surface communications and the advanced wideband Direct Sequence Code Division Multiple Access (DSCDMA) conceptual systems utilizing phased-array technology that will evolve in the next decade. Time Domain Multiple Access (TDMA) and Code Division Multiple Access (CDMA) are standard Media Access Control (MAC) techniques that can be incorporated into lunar surface communications architectures. Another novel hybrid technique that is recently being developed for use with smart antenna technology combines the advantages of CDMA with those of TDMA. The relatively new and sundry wireless LAN data link layer protocols that are continually under development offer distinct advantages for lunar surface applications over the legacy protocols which are not wireless. Also several communication transport and routing protocols can be chosen with characteristics commensurate with smart antenna systems to provide spacecraft communications for links exhibiting high capacity on the surface of the Moon. The proper choices depend on the specific communication requirements.

  12. Communication, Control, and Computer Access for Disabled and Elderly Individuals. ResourceBook 4: Update to Books 1, 2, and 3.

    Science.gov (United States)

    Borden, Peter A., Ed.; Vanderheiden, Gregg C., Ed.

    This update to the three-volume first edition of the "Rehab/Education ResourceBook Series" describes special software and products pertaining to communication, control, and computer access, designed specifically for the needs of disabled and elderly people. The 22 chapters cover: speech aids; pointing and typing aids; training and communication…

  13. Detection and response to unauthorized access to a communication device

    Science.gov (United States)

    Smith, Rhett; Gordon, Colin

    2015-09-08

    A communication gateway consistent with the present disclosure may detect unauthorized physical or electronic access and implement security actions in response thereto. A communication gateway may provide a communication path to an intelligent electronic device (IED) using an IED communications port configured to communicate with the IED. The communication gateway may include a physical intrusion detection port and a network port. The communication gateway may further include control logic configured to evaluate physical intrusion detection signal. The control logic may be configured to determine that the physical intrusion detection signal is indicative of an attempt to obtain unauthorized access to one of the communication gateway, the IED, and a device in communication with the gateway; and take a security action based upon the determination that the indication is indicative of the attempt to gain unauthorized access.

  14. Digital autonomous terminal access communications

    Science.gov (United States)

    Novacki, S.

    1987-01-01

    A significant problem for the Bus Monitor Unit is to identify the source of a given transmission. This problem arises from the fact that the label which identifies the source of the transmission as it is put into the bus is intercepted by the Digital Autonomous Terminal Access Communications (DATAC) terminal and removed from the transmission. Thus, a given subsystem will see only data associated with a label and never the identifying label itself. The Bus Monitor must identify the source of the transmission so as to be able to provide some type of error identification/location in the event that some problem with the data transmission occurs. Steps taken to alleviate this problem by modifications to the DATAC terminal are discussed.

  15. Android Access Control Extension

    Directory of Open Access Journals (Sweden)

    Anton Baláž

    2015-12-01

    Full Text Available The main objective of this work is to analyze and extend security model of mobile devices running on Android OS. Provided security extension is a Linux kernel security module that allows the system administrator to restrict program's capabilities with per-program profiles. Profiles can allow capabilities like network access, raw socket access, and the permission to read, write, or execute files on matching paths. Module supplements the traditional Android capability access control model by providing mandatory access control (MAC based on path. This extension increases security of access to system objects in a device and allows creating security sandboxes per application.

  16. Access Control Enforcement Testing

    OpenAIRE

    El Kateb, Donia; Elrakaiby, Yehia; Mouelhi, Tejeddine; Le Traon, Yves

    2012-01-01

    A policy-based access control architecture com- prises Policy Enforcement Points (PEPs), which are modules that intercept subjects access requests and enforce the access decision reached by a Policy Decision Point (PDP), the module implementing the access decision logic. In applications, PEPs are generally implemented manually, which can introduce errors in policy enforcement and lead to security vulnerabilities. In this paper, we propose an approach to systematically test and validate the co...

  17. ACCESS Pointing Control System

    Science.gov (United States)

    Brugarolas, Paul; Alexander, James; Trauger, John; Moody, Dwight; Egerman, Robert; Vallone, Phillip; Elias, Jason; Hejal, Reem; Camelo, Vanessa; Bronowicki, Allen; O'Connor, David; Partrick, Richard; Orzechowski, Pawel; Spitter, Connie; Lillie, Chuck

    2010-01-01

    ACCESS (Actively-Corrected Coronograph for Exoplanet System Studies) was one of four medium-class exoplanet concepts selected for the NASA Astrophysics Strategic Mission Concept Study (ASMCS) program in 2008/2009. The ACCESS study evaluated four major coronograph concepts under a common space observatory. This paper describes the high precision pointing control system (PCS) baselined for this observatory.

  18. IBM 3705 Communications Controller

    CERN Multimedia

    1972-01-01

    The IBM 3705 Communications Controller is a simple computer which attaches to an IBM System/360 or System/370. Its purpose is to connect communication lines to the mainframe channel. It was a first communications controller of the popular IBM 37xx series.

  19. Analysing Access Control Specifications

    DEFF Research Database (Denmark)

    Probst, Christian W.; Hansen, René Rydhof

    2009-01-01

    . Recent events have revealed intimate knowledge of surveillance and control systems on the side of the attacker, making it often impossible to deduce the identity of an inside attacker from logged data. In this work we present an approach that analyses the access control configuration to identify the set......When prosecuting crimes, the main question to answer is often who had a motive and the possibility to commit the crime. When investigating cyber crimes, the question of possibility is often hard to answer, as in a networked system almost any location can be accessed from almost anywhere. The most...... of credentials needed to reach a certain location in a system. This knowledge allows to identify a set of (inside) actors who have the possibility to commit an insider attack at that location. This has immediate applications in analysing log files, but also nontechnical applications such as identifying possible...

  20. Transformational leadership: visibility, accessibility, and communication.

    Science.gov (United States)

    Clavelle, Joanne T

    2012-01-01

    The chief nursing officer of a Magnet® organization is a dynamic, transformational leader who develops and communicates a strong vision for nursing excellence and creates a foundation for exemplary nursing practice and excellent patient care. Transformational leadership is a core component of the Magnet Model®. The 3rd subcomponent--visibility, accessibility, and communication--is the focus of this article.

  1. Programmable data communications controller requirements

    Science.gov (United States)

    1977-01-01

    The design requirements for a Programmable Data Communications Controller (PDCC) that reduces the difficulties in attaching data terminal equipment to a computer are presented. The PDCC is an interface between the computer I/O channel and the bit serial communication lines. Each communication line is supported by a communication port that handles all line control functions and performs most terminal control functions. The port is fabricated on a printed circuit board that plugs into a card chassis, mating with a connector that is joined to all other card stations by a data bus. Ports are individually programmable; each includes a microprocessor, a programmable read-only memory for instruction storage, and a random access memory for data storage.

  2. Information, communication, travel behaviour and accessibility

    NARCIS (Netherlands)

    Wee, van B.; Chorus, C.; Geurs, K.T.

    2013-01-01

    Over the past two decades many papers have been published on the impact of Information and Communication Technologies (ICT) on travel behavior, but the literature focusing on the impact of ICT on accessibility is relatively scarce. In this paper we give an overview of the impact of ICT on four compo

  3. Digital Autonomous Terminal Access Communication (DATAC) system

    Science.gov (United States)

    Novacki, Stanley M., III

    1987-01-01

    In order to accommodate the increasing number of computerized subsystems aboard today's more fuel efficient aircraft, the Boeing Co. has developed the DATAC (Digital Autonomous Terminal Access Control) bus to minimize the need for point-to-point wiring to interconnect these various systems, thereby reducing total aircraft weight and maintaining an economical flight configuration. The DATAC bus is essentially a local area network providing interconnections for any of the flight management and control systems aboard the aircraft. The task of developing a Bus Monitor Unit was broken down into four subtasks: (1) providing a hardware interface between the DATAC bus and the Z8000-based microcomputer system to be used as the bus monitor; (2) establishing a communication link between the Z8000 system and a CP/M-based computer system; (3) generation of data reduction and display software to output data to the console device; and (4) development of a DATAC Terminal Simulator to facilitate testing of the hardware and software which transfer data between the DATAC's bus and the operator's console in a near real time environment. These tasks are briefly discussed.

  4. Physical Access Control Database -

    Data.gov (United States)

    Department of Transportation — This data set contains the personnel access card data (photo, name, activation/expiration dates, card number, and access level) as well as data about turnstiles and...

  5. Function-Based Access Control (FBAC): From Access Control Matrix to Access Control Tensor

    OpenAIRE

    Desmedt, Yvo; Shaghaghi, Arash

    2016-01-01

    Security researchers have stated that the core concept behind current implementations of access control predates the Internet. These assertions are made to pinpoint that there is a foundational gap in this field, and one should consider revisiting the concepts from the ground up. Moreover, Insider threats, which are an increasing threat vector against organizations are also associated with the failure of access control. Access control models derived from access control matrix encompass three ...

  6. Miniature Transportable Communications Central (MTCC): answering law enforcement needs for worldwide access to command, control, communications, and intelligence (C3I)

    Science.gov (United States)

    Maxey, W. John

    1997-02-01

    The Mini-Transportable Communications Central (MTCC), developed by Rome Laboratories C3 Directorate, provides the U.S. Coast Guard (USCG) with a transportable, fast reaction communications terminal. The MTCC is capable of operating as a self-contained miniature command center supporting efforts such as the President's War on Drugs, or the rescue services necessary in the wake of man-made or natural disasters. The MTCC is capable of communicating with field elements including ships, small water-craft, aircraft, other elements of the USCG law enforcement agencies (LEAs), the FAA, and a wide range of U.S. and foreign armed forces. The MTCC terminal is contained in a trailer-mounted shelter suitable for towing by a 3/4 ton truck or for transport by C-130 aircraft. The MTCC provides simultaneous one-way and two-way communications in the HF, VHF, and UHF frequency bands, as well as the INMARSAT international satellite band. The MTCC also offers communications through subscriber and trunk telephone connectivity via ISDN compatible PABX. The MTCC's three channel operations personnel cellular telephone system provides self-contained cellular telephone operations in the vicinity of the deployed shelter. In the USCG application, an operator console inside the air-conditioned shelter serves as the source and destination for voice, data, and fax traffic, by means of secure fax telephone, operator headsets, and a powerful computer workstation that provides word processing, e-mail, and data communications capabilities. The communications operator may reconfigure the system for a specific mission by means of patchfields that enable the selection of radios, encrypted or clear-text operations, audio termination, and antennas.

  7. Access to augmentative and alternative communication: new technologies and clinical decision-making.

    Science.gov (United States)

    Fager, Susan; Bardach, Lisa; Russell, Susanne; Higginbotham, Jeff

    2012-01-01

    Children with severe physical impairments require a variety of access options to augmentative and alternative communication (AAC) and computer technology. Access technologies have continued to develop, allowing children with severe motor control impairments greater independence and access to communication. This article will highlight new advances in access technology, including eye and head tracking, scanning, and access to mainstream technology, as well as discuss future advances. Considerations for clinical decision-making and implementation of these technologies will be presented along with case illustrations.

  8. Multiple access communications using wavelet technology

    Science.gov (United States)

    Orr, Richard S.; Pike, Cameron; Bates, Margaret L.

    1995-04-01

    A class of waveforms developed for covert, or low probability of intercept/detection (LPI/D) communications has been tested for its applicability to code-division multiple access (CDMA) communications. This paper reports some results of the investigation. The waveforms, constructed by techniques based on wavelet transforms, show the characteristics of bandpass Gaussian noise under a number of statistical tests. We refer to these as single-scale waveforms because of an aspect of their construction. By a combination of analysis and simulation, the single-scale waveforms have been compared to conventional CDMA techniques, and it is concluded that on the additive, white Gaussian noise channel, they outperform the conventional by 75 - 200% in capacity (number of supportable users per unit bandwidth at fixed SNR and bit error rate).

  9. Controlling Access to RDF Graphs

    Science.gov (United States)

    Flouris, Giorgos; Fundulaki, Irini; Michou, Maria; Antoniou, Grigoris

    One of the current barriers towards realizing the huge potential of Future Internet is the protection of sensitive information, i.e., the ability to selectively expose (or hide) information to (from) users depending on their access privileges. Given that RDF has established itself as the de facto standard for data representation over the Web, our work focuses on controlling access to RDF data. We present a high-level access control specification language that allows fine-grained specification of access control permissions (at triple level) and formally define its semantics. We adopt an annotation-based enforcement model, where a user can explicitly associate data items with annotations specifying whether the item is accessible or not. In addition, we discuss the implementation of our framework, propose a set of dimensions that should be considered when defining a benchmark to evaluate the different access control enforcement models and present the results of our experiments conducted on different Semantic Web platforms.

  10. Time division multiple access for vehicular communications

    CERN Document Server

    Omar, Hassan Aboubakr

    2014-01-01

    This brief focuses on medium access control (MAC) in vehicular ad hoc networks (VANETs), and presents VeMAC, a novel MAC scheme based on distributed time division multiple access (TDMA) for VANETs. The performance of VeMAC is evaluated via mathematical analysis and computer simulations in comparison with other existing MAC protocols, including the IEEE 802.11p standard. This brief aims at proposing TDMA as a suitable MAC scheme for VANETs, which can support the quality-of-service requirements of high priority VANET applications.

  11. Network Access Control For Dummies

    CERN Document Server

    Kelley, Jay; Wessels, Denzil

    2009-01-01

    Network access control (NAC) is how you manage network security when your employees, partners, and guests need to access your network using laptops and mobile devices. Network Access Control For Dummies is where you learn how NAC works, how to implement a program, and how to take real-world challenges in stride. You'll learn how to deploy and maintain NAC in your environment, identify and apply NAC standards, and extend NAC for greater network security. Along the way you'll become familiar with what NAC is (and what it isn't) as well as the key business drivers for deploying NAC.Learn the step

  12. Multiple Access Technologies for Cellular M 2M Communications

    Institute of Scientific and Technical Information of China (English)

    Mahyar Shirvanimoghaddam; Sarah J. Johnson

    2016-01-01

    This paper reviews the multiple access techniques for machine⁃to⁃machine (M2M) communications in future wireless cellular net⁃works. M2M communications aims at providing the communication infrastructure for the emerging Internet of Things (IoT), which will revolutionize the way we interact with our surrounding physical environment. We provide an overview of the multiple access strategies and explain their limitations when used for M2M communications. We show the throughput efficiency of different multi⁃ple access techniques when used in coordinated and uncoordinated scenarios. Non⁃orthogonal multiple access (NOMA) is also shown to support a larger number of devices compared to orthogonal multiple access techniques, especially in uncoordinated sce⁃narios. We also detail the issues and challenges of different multiple access techniques to be used for M2M applications in cellu⁃lar networks.

  13. Performance management of multiple access communication networks

    Science.gov (United States)

    Lee, Suk; Ray, Asok

    1993-12-01

    This paper focuses on conceptual design, development, and implementation of a performance management tool for computer communication networks to serve large-scale integrated systems. The objective is to improve the network performance in handling various types of messages by on-line adjustment of protocol parameters. The techniques of perturbation analysis of Discrete Event Dynamic Systems (DEDS), stochastic approximation (SA), and learning automata have been used in formulating the algorithm of performance management. The efficacy of the performance management tool has been demonstrated on a network testbed. The conceptual design presented in this paper offers a step forward to bridging the gap between management standards and users' demands for efficient network operations since most standards such as ISO (International Standards Organization) and IEEE address only the architecture, services, and interfaces for network management. The proposed concept of performance management can also be used as a general framework to assist design, operation, and management of various DEDS such as computer integrated manufacturing and battlefield C(sup 3) (Command, Control, and Communications).

  14. Developing Communication Access Standards to Maximize Community Inclusion for People with Communication Support Needs

    Science.gov (United States)

    Solarsh, Barbara; Johnson, Hilary

    2017-01-01

    People with communication support needs experience barriers that limit their social inclusion in society. A community approach such as "communication access" that targets changing attitudes, skills, and resources may assist in facilitating community participation. The authors describe the development of communication access from 2008 in…

  15. Unifications and extensions of the multiple access communications problem

    Science.gov (United States)

    Molle, M. L.

    1981-08-01

    Multiple access protocols permit a broadcast communications channel to be shared by a large number of stations under distributed control. It is assumed that only one message at a time can be transmitted successfully over the common channel. A local optimality condition for synchronous multiple access protocols was derived and it is shown that many known protocols are special cases of this condition. A survey of much of the recent work on infinite population tree algorithms that use the history of channel activity to carry out short-range dynamic scheduling is included. An approach is presented for deriving upper bounds on the maximum stable throughput with finite average delay for infinite population protocols.

  16. Communication access to businesses and organizations for people with complex communication needs.

    Science.gov (United States)

    Collier, Barbara; Blackstone, Sarah W; Taylor, Andrew

    2012-12-01

    Human rights legislation and anti-discrimination and accessibility laws exist in many countries and through international conventions and treaties. To varying degrees, these laws protect the rights of people with disabilities to full and equal access to goods and services. Yet, the accessibility requirements of people with complex communication needs (CCN) are not well represented in the existing accessibility literature. This article describes the results of surveys completed by disability service providers and individuals with CCN due to cerebral palsy, developmental delay, and acquired disabilities. It identifies accessibility requirements for people with CCN for face-to-face communication; comprehension of spoken language; telephone communication; text and print-based communication; Internet, email, and social media interactions; and written communication. Recommendations are made for communication accessibility accommodations in regulations, guidelines, and practices.

  17. Accessible information for people with complex communication needs.

    Science.gov (United States)

    Owens, Janet S

    2006-09-01

    Information can be empowering if it is accessible. While a number of known information access barriers have been reported for the broader group of people with disabilities, specific information issues for people with complex communication needs have not been previously reported. In this consumer-focused study, the accessibility of information design and dissemination practices were discussed by 17 people with complex communication needs; by eight parents, advocates, therapists, and agency representatives in focus groups; and by seven individuals in individual interviews. Participants explored issues and made recommendations for content, including language, visual and audio supports; print accessibility; physical access; and human support for information access. Consumer-generated accessibility guidelines were an outcome of this study.

  18. Flexible access control for dynamic collaborative environments

    NARCIS (Netherlands)

    Dekker, Mari Antonius Cornelis

    2009-01-01

    Access control is used in computer systems to control access to confidential data. In this thesis we focus on access control for dynamic collaborative environments where multiple users and systems access and exchange data in an ad hoc manner. In such environments it is difficult to protect confident

  19. Open access and scholarly communication, part 4

    CERN Document Server

    Eden, Brad

    2009-01-01

    This fourth e-book on the subject of open access in the academic field includes a Latin American case study on open access penetration, a paper from Germany on the promotion of OA illustrated by a project at the University of Konstanz, and a case study on OA at Bioline International, a non-profit scholarly publications aggregator, distributor, publisher and publishing assistance service.

  20. LTE-advanced random access mechanism for M2M communication: A review

    Science.gov (United States)

    Mustafa, Rashid; Sarowa, Sandeep; Jaglan, Reena Rathee; Khan, Mohammad Junaid; Agrawal, Sunil

    2016-03-01

    Machine Type Communications (MTC) enables one or more self-sufficient machines to communicate directly with one another without human interference. MTC applications include smart grid, security, e-Health and intelligent automation system. To support huge numbers of MTC devices, one of the challenging issues is to provide a competent way for numerous access in the network and to minimize network overload. In this article, the different control mechanisms for overload random access are reviewed to avoid congestion caused by random access channel (RACH) of MTC devices. However, past and present wireless technologies have been engineered for Human-to-Human (H2H) communications, in particular, for transmission of voice. Consequently the Long Term Evolution (LTE) -Advanced is expected to play a central role in communicating Machine to Machine (M2M) and are very optimistic about H2H communications. Distinct and unique characteristics of M2M communications create new challenges from those in H2H communications. In this article, we investigate the impact of massive M2M terminals attempting random access to LTE-Advanced all at once. We discuss and review the solutions to alleviate the overload problem by Third Generation Partnership Project (3GPP). As a result, we evaluate and compare these solutions that can effectively eliminate the congestion on the random access channel for M2M communications without affecting H2H communications.

  1. The Effects of Information and Communication Technologies on Accessibility

    NARCIS (Netherlands)

    Lu, R.

    2015-01-01

    It is expected that information and communication technology (ICT) can have great impacts on traveler’s accessibility. However, understanding of the effects of ICT on accessibility is still limited. Consequently, this thesis aims to increase the understanding of such effects. The thesis develops a

  2. The Effects of Information and Communication Technologies on Accessibility

    NARCIS (Netherlands)

    Lu, R.

    2015-01-01

    It is expected that information and communication technology (ICT) can have great impacts on traveler’s accessibility. However, understanding of the effects of ICT on accessibility is still limited. Consequently, this thesis aims to increase the understanding of such effects. The thesis develops a g

  3. Code-Expanded Random Access for Machine-Type Communications

    DEFF Research Database (Denmark)

    Kiilerich Pratas, Nuno; Thomsen, Henning; Stefanovic, Cedomir

    2012-01-01

    Abstract—The random access methods used for support of machine-type communications (MTC) in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. Motivated by the random access method employed in LTE, we propose...

  4. Controlling Access to Suicide Means

    Directory of Open Access Journals (Sweden)

    Miriam Iosue

    2011-12-01

    Full Text Available Background: Restricting access to common means of suicide, such as firearms, toxic gas, pesticides and other, has been shown to be effective in reducing rates of death in suicide. In the present review we aimed to summarize the empirical and clinical literature on controlling the access to means of suicide. Methods: This review made use of both MEDLINE, ISI Web of Science and the Cochrane library databases, identifying all English articles with the keywords “suicide means”, “suicide method”, “suicide prediction” or “suicide prevention” and other relevant keywords. Results: A number of factors may influence an individual’s decision regarding method in a suicide act, but there is substantial support that easy access influences the choice of method. In many countries, restrictions of access to common means of suicide has lead to lower overall suicide rates, particularly regarding suicide by firearms in USA, detoxification of domestic and motor vehicle gas in England and other countries, toxic pesticides in rural areas, barriers at jumping sites and hanging, by introducing “safe rooms” in prisons and hospitals. Moreover, decline in prescription of barbiturates and tricyclic antidepressants (TCAs, as well as limitation of drugs pack size for paracetamol and salicylate has reduced suicides by overdose, while increased prescription of SSRIs seems to have lowered suicidal rates. Conclusions: Restriction to means of suicide may be particularly effective in contexts where the method is popular, highly lethal, widely available, and/or not easily substituted by other similar methods. However, since there is some risk of means substitution, restriction of access should be implemented in conjunction with other suicide prevention strategies.

  5. Access Request Trustworthiness in Weighted Access Control Framework

    Institute of Scientific and Technical Information of China (English)

    WANG Lun-wei; LIAO Xiang-ke; WANG Huai-min

    2005-01-01

    Weighted factor is given to access control policies to express the importance of policy and its effect on access control decision. According to this weighted access control framework, a trustworthiness model for access request is also given. In this model, we give the measure of trustworthiness factor to access request, by using some idea of uncertainty reasoning of expert system, present and prove the parallel propagation formula of request trustworthiness factor among multiple policies, and get the final trustworthiness factor to decide whether authorizing. In this model, authorization decision is given according to the calculation of request trustworthiness factor, which is more understandable, more suitable for real requirement and more powerful for security enhancement than traditional methods. Meanwhile the finer access control granularity is another advantage.

  6. Demand access communications for TDRSS users

    Science.gov (United States)

    Zillig, David; Weinberg, Aaron; Mcomber, Robert

    1994-01-01

    The Tracking and Data Relay Satellite System (TDRSS) has long been used to provide reliable low and high-data rate relay services between user spacecraft in Earth orbit and the ground. To date, these TDRSS services have been implemented via prior scheduling based upon estimates of user needs and mission event timelines. While this approach may be necessary for large users that require greater amounts of TDRSS resources, TDRSS can potentially offer the planned community of smaller science missions (e.g., the small explorer missions), and other emerging users, the unique opportunity for services on demand. In particular, innovative application of the existing TDRSS Multiple Access (MA) subsystem, with its phased array antenna, could be used to implement true demand access services without modification to either the TDRSS satellites or the user transponder, thereby introducing operational and performance benefits to both the user community and the Space Network. In this paper, candidate implementations of demand access service via the TDRSS MA subsystem are examined in detail. Both forward and return link services are addressed and a combination of qualitative and quantitative assessments are provided. The paper also identifies further areas for investigation in this ongoing activity that is being conducted by GSFC/Code 531 under the NASA Code O Advanced Systems Program.

  7. Key issues of multiple access technique for LEO satellite communication systems

    Institute of Scientific and Technical Information of China (English)

    温萍萍; 顾学迈

    2004-01-01

    The large carrier frequency shift caused by the high-speed movement of satellite (Doppler effects) and the propagation delay on the up-down link are very critical issues in an LEO satellite communication system, which affects both the selection and the implementation of a suitable access method. A Doppler based multiple access technique is used here to control the flow and an MPRMA-HS protocol is proposed for the application in LEO satellite communication systems. The extended simulation trials prove that the proposed scheme seems to be a very promising access method.

  8. Adaptive Power Control for Space Communications

    Science.gov (United States)

    Thompson, Willie L., II; Israel, David J.

    2008-01-01

    This paper investigates the implementation of power control techniques for crosslinks communications during a rendezvous scenario of the Crew Exploration Vehicle (CEV) and the Lunar Surface Access Module (LSAM). During the rendezvous, NASA requires that the CEV supports two communication links: space-to-ground and crosslink simultaneously. The crosslink will generate excess interference to the space-to-ground link as the distances between the two vehicles decreases, if the output power is fixed and optimized for the worst-case link analysis at the maximum distance range. As a result, power control is required to maintain the optimal power level for the crosslink without interfering with the space-to-ground link. A proof-of-concept will be described and implemented with Goddard Space Flight Center (GSFC) Communications, Standard, and Technology Lab (CSTL).

  9. ITS Multi-path Communications Access Decision Scheme

    Directory of Open Access Journals (Sweden)

    Miroslav Svitek

    2008-02-01

    Full Text Available Intelligent Transport Systems (ITS require widely spread and guarantied quality communications services. Method of ITS decomposition to set of subsystems and quantification of communications subsystems parameters is introduced. Due to typical complexity of the IST solution and mobility as the typical system elements property idea of communications systems with multipath multivendor structures is adopted. Resolution of seamless switching within a set of available wireless access solutions is presented. CALM based system or specifically designed and configured L3/L2 switching can be relevant solution for multi-path access communication system. These systems meet requirements of the seamless secure communications functionality within even extensive cluster of moving objects. Competent decision processes based on precisely quantified system requirements and each performance indicator tolerance range must be implemented to keep service up and running with no influence of continuously changing conditions in time and served space. Method of different paths service quality evaluation and selection of the best possible active communications access path is introduced. Proposed approach is based on Kalman filtering, which separates reasonable part of noise and also allows prediction of the individual parameters near future behavior. Presented classification algorithm applied on filtered measured data combined with deterministic parameters is trained using training data, i.e. combination of parameters vectors line and relevant decisions. Quality of classification is dependent on the size and quality of the training sets. This method is studied within projects e-Ident, DOTEK and SRATVU which are elaborating results of project CAMNA.

  10. An Access Control Framework for Reflective Middleware

    Institute of Scientific and Technical Information of China (English)

    Gang Huang; Lian-Shan Sun

    2008-01-01

    Reflective middleware opens up the implementation details of middleware platform and applications at runtime for improving the adaptability of middleware-based systems. However, such openness brings new challenges to access control of the middleware-based systems.Some users can access the system via reflective entities, which sometimes cannot be protected by access control mechanisms of traditional middleware. To deliver high adaptability securely, reflective middleware should be equipped with proper access control mechanisms for potential access control holes induced by reflection. One reason of integrating these mechanisms in reflective middleware is that one goal of reflective middleware is to equip applications with reflection capabilities as transparent as possible. This paper studies how to design a reflective J2EE middlewarePKUAS with access control in mind. At first, a computation model of reflective system is built to identify all possible access control points induced by reflection. Then a set of access control mechanisms, including the wrapper of MBeans and a hierarchy of Java class loaders, are equipped for controlling the identified access control points. These mechanisms together with J2EE access control mechanism form the access control framework for PKUAS. The paper evaluates the security and the performance overheads of the framework in quality and quantity.

  11. Enhancing Radio Access Network Performance over LTE-A for Machine-to-Machine Communications under Massive Access

    Directory of Open Access Journals (Sweden)

    Fatemah Alsewaidi

    2016-01-01

    Full Text Available The expected tremendous growth of machine-to-machine (M2M devices will require solutions to improve random access channel (RACH performance. Recent studies have shown that radio access network (RAN performance is degraded under the high density of devices. In this paper, we propose three methods to enhance RAN performance for M2M communications over the LTE-A standard. The first method employs a different value for the physical RACH configuration index to increase random access opportunities. The second method addresses a heterogeneous network by using a number of picocells to increase resources and offload control traffic from the macro base station. The third method involves aggregation points and addresses their effect on RAN performance. Based on evaluation results, our methods improved RACH performance in terms of the access success probability and average access delay.

  12. Efficient Access Control in Multimedia Social Networks

    Science.gov (United States)

    Sachan, Amit; Emmanuel, Sabu

    Multimedia social networks (MMSNs) have provided a convenient way to share multimedia contents such as images, videos, blogs, etc. Contents shared by a person can be easily accessed by anybody else over the Internet. However, due to various privacy, security, and legal concerns people often want to selectively share the contents only with their friends, family, colleagues, etc. Access control mechanisms play an important role in this situation. With access control mechanisms one can decide the persons who can access a shared content and who cannot. But continuously growing content uploads and accesses, fine grained access control requirements (e.g. different access control parameters for different parts in a picture), and specific access control requirements for multimedia contents can make the time complexity of access control to be very large. So, it is important to study an efficient access control mechanism suitable for MMSNs. In this chapter we present an efficient bit-vector transform based access control mechanism for MMSNs. The proposed approach is also compatible with other requirements of MMSNs, such as access rights modification, content deletion, etc. Mathematical analysis and experimental results show the effectiveness and efficiency of our proposed approach.

  13. Communicating Networked Control Systems

    Science.gov (United States)

    2007-03-31

    Bahamas, pages 1010-1015. 64. Carmen Del Vecchio and I.C. Paschalidis, “Supply Contracts with Service Level Requirements”, Proceedings of the IFAC...control using Monte Carlo sensing,” Proc. IEEE International Conference on Robotics and Automation, pp. 3058-3063, 2005. 10. S.B. Andersson, A.A. Handzel, V...Analysis, Madrid Spain. 20. S. Andersson and D. Hristu-Varsakelis, “Language-based feedback control using Monte -Carlo sensing”, to be subm. To IEEE Int’l

  14. Distributed reservation control protocols for random access broadcasting channels

    Science.gov (United States)

    Greene, E. P.; Ephremides, A.

    1981-05-01

    Attention is given to a communication network consisting of an arbitrary number of nodes which can communicate with each other via a time-division multiple access (TDMA) broadcast channel. The reported investigation is concerned with the development of efficient distributed multiple access protocols for traffic consisting primarily of single packet messages in a datagram mode of operation. The motivation for the design of the protocols came from the consideration of efficient multiple access utilization of moderate to high bandwidth (4-40 Mbit/s capacity) communication satellite channels used for the transmission of short (1000-10,000 bits) fixed length packets. Under these circumstances, the ratio of roundtrip propagation time to packet transmission time is between 100 to 10,000. It is shown how a TDMA channel can be adaptively shared by datagram traffic and constant bandwidth users such as in digital voice applications. The distributed reservation control protocols described are a hybrid between contention and reservation protocols.

  15. Research of Communication of Lubrication Station Control System Based on WebAccess%基于WebAccess的润滑站控制系统通信的研究

    Institute of Scientific and Technical Information of China (English)

    巴鹏; 张雨; 焦圳

    2015-01-01

    Through establishing the communication between site plant and IPC configuration software WebAccess, it achieves the filling oil monitoring, operation control and data processing of the lubrication station control system. This arti-cle uses VB to establish procedures for communication as the data exchange program, combining configuration software WebAccess to build the lubrication station automation injection oil monitoring and management system. It can effectively solve the configuration software lack of driver and monitoring system of data transmission is not timely, inaccurate data re-cords, and other issues. The experiment results show that the system is easy to operate, accurate data transmission, and stable running and easy to maintain. It is the development trend of lubrication station in the future.%通过建立现场设备与工控机组态软件WebAccess的通信,实现了对润滑站控制系统加注油品监测、运行控制和数据处理。本文采用VB建立通讯连接程序作为数据交换程序,结合组态软件WebAccess建立润滑站自动加注油品的监控与管理系统,有效地解决了组态软件缺乏驱动和监控系统数据传递不及时、数据记录不准确等问题。实验结果表明:该系统易于操作,数据传输准确,运行稳定和便于维护,是润滑站今后发展的趋势。

  16. Managing Delegation in Access Control Models

    CERN Document Server

    Ghorbel-Talbi, Meriam Ben; Cuppens-Boulahia, Nora; Bouhoula, Adel; 10.1109/ADCOM.2007.105

    2010-01-01

    In the field of access control, delegation is an important aspect that is considered as a part of the administration mechanism. Thus, a complete access control must provide a flexible administration model to manage delegation. Unfortunately, to our best knowledge, there is no complete model for describing all delegation requirements for role-based access control. Therefore, proposed models are often extended to consider new delegation characteristics, which is a complex task to manage and necessitate the redefinition of these models. In this paper we describe a new delegation approach for extended role-based access control models. We show that our approach is flexible and is sufficient to manage all delegation requirements.

  17. Channel Coding in Random Access Communication over Compound Channels

    CERN Document Server

    Wang, Zheng

    2011-01-01

    Due to the short and bursty incoming messages, channel access activities in a wireless random access system are often fractional. The lack of frequent data support consequently makes it difficult for the receiver to estimate and track the time varying channel states with high precision. This paper investigates random multiple access communication over a compound wireless channel where channel realization is known neither at the transmitters nor at the receiver. An achievable rate and error probability tradeoff bound is derived under the non-asymptotic assumption of a finite codeword length. The results are then extended to the random multiple access system where the receiver is only interested in decoding messages from a user subset.

  18. Campus Access Control System RFID Based

    Directory of Open Access Journals (Sweden)

    Mr. SANTHOSH S

    2012-06-01

    Full Text Available Radio frequency identification (RFID technology has helped many organizations to reduce cost. Nevertheless, there are challenges and issues associated with RFID adoption. The most common internal challenge for many organizations is justifying the investment and modification of processes. The focus of this project is to show the business value of RFID technology and its applications. The important issue is the security level of the whole campus because it needs to be carefully differentiated. Dormitories and special research laboratories should benefit from higher levels of security than any other campuses. The key to the problem is represented by the new Radio Frequency Identification (RFID which can support contactless cards with memory. The most important feature of the proposed system is the updating of access permission level at any time for the user based on the availability of that user. The data transfer from the reader to the database was done using wireless communication (RF communication. To achieve this here RF transmitter and the RF receiver is used. The data which is read by the reader is sent to the microcontroller. Then from the controller we can transfer the data to the database by using the UART module (serial communication which is inbuilt in the microcontroller through RF transmitter. RF receiver of the same frequency at the receiver end receives and then stores the data in the database. RF transmitter and Receiver – frequency for transmitting and receiving the data depends on the user as per the requirement for the application and it is based on the range of distance. For the data encoding and decoding process HCS-101 protocol is used.

  19. Proximity Displays for Access Control

    Science.gov (United States)

    Vaniea, Kami

    2012-01-01

    Managing access to shared digital information, such as photographs and documents. is difficult for end users who are accumulating an increasingly large and diverse collection of data that they want to share with others. Current policy-management solutions require a user to proactively seek out and open a separate policy-management interface when…

  20. Privacy Preservation in Role-based Access Control Model

    Directory of Open Access Journals (Sweden)

    Zuo Chen

    2011-08-01

    Full Text Available Privacy preservation is a crucial problem in resource sharing and collaborating among multi-domains. Based on this problem, we propose a role-based access control model for privacy preservation. This scheme avoided the privacy leakage of resources while implementing access control, and it has the advantage of lower communication overhead. We demonstrate this scheme meets the IND-CCA2 semantic security by using random oracle. The simulation result shows this scheme has better execution efficiency and application effects.

  1. Code-Expanded Random Access for Machine-Type Communications

    DEFF Research Database (Denmark)

    Kiilerich Pratas, Nuno; Thomsen, Henning; Stefanovic, Cedomir

    2012-01-01

    a novel approach that is able to sustain a wide random access load range, while preserving the physical layer unchanged and incurring minor changes in the medium access control layer. The proposed scheme increases the amount of available contention resources, without resorting to the increase of system...... of an increased number of MTC users. We present the framework and analysis of the proposed code-expanded random access method and show that our approach supports load regions that are beyond the reach of current systems....

  2. Access control and personal identification systems

    CERN Document Server

    Bowers, Dan M

    1988-01-01

    Access Control and Personal Identification Systems provides an education in the field of access control and personal identification systems, which is essential in selecting the appropriate equipment, dealing intelligently with vendors in purchases of the equipment, and integrating the equipment into a total effective system. Access control devices and systems comprise an important part of almost every security system, but are seldom the sole source of security. In order for the goals of the total system to be met, the other portions of the security system must also be well planned and executed

  3. Making the innovation case in Open Access scholary communication

    CERN Document Server

    CERN. Geneva

    2005-01-01

    It seems almost unnecessary to have to elaborate additional reasons for the adoption of Open Access scholarly communication (OA sc) as manifested through Open Access journals and self-archiving practices. To those active within the OA arena, the case has been convincingly made, and current arguments merely need to be disseminated beyond the Library and Information Science (LIS) sphere. However, it is my contention that a convincing argument for OA sc needs to be launched from the Science Policy perspective if any government mandated pro-OA policy changes are to be effected. This paper, then, is an attempt at taking the OA discussion beyond the LIS arena and into the realm of Science and Innovation Policy. Using Innovation Theory as its theoretical framework, it is argued that Open Access scholarly communication can only serve to bolster Innovation Systems, be they national, regional, or sectoral. The case of South Africa is taken as an illustrative example, though the case can and will be generalised to beyon...

  4. Cooperative controls with intermittent communication

    Science.gov (United States)

    Shen, Dan; Chen, Genshe; Cruz, Jose B., Jr.; Pham, Khanh; Blasch, Erik; Lynch, Robert

    2010-04-01

    In this paper, we propose a solution to the cooperative path planning with limited communication problem in two phases. In the first (offline) phase, a Pareto-optimal path problem is formulated to find a reference path and the graph cuts minimization method is used to speedily calculate the optimal solution. In the second (online) phase, a foraging algorithm is used to dynamically refine the reference path to meet the dynamic constraints of unmanned aerial vehicle (UAVs), during which an open-loop feedback optimal (OLFO) controller is used to estimate the states which may be unavailable due to infrequent battlefield information updates. Furthermore, an adaptive Markov decision process is proposed to deal with intermittent asynchronous information flow. The method is demonstrated in a simulation for a swarm of Unmanned Air Vehicle (UAV) teams with various communication ranges.

  5. Access control, security, and trust a logical approach

    CERN Document Server

    Chin, Shiu-Kai

    2010-01-01

    Access Control, Security, Trust, and Logic Deconstructing Access Control Decisions A Logical Approach to Access Control PRELIMINARIES A Language for Access ControlSets and Relations Syntax SemanticsReasoning about Access Control Logical RulesFormal Proofs and Theorems Soundness of Logical RulesBasic Concepts Reference Monitors Access Control Mechanisms: Tickets and Lists Authentication Security PoliciesConfidentiality, Integrity, and Availability Discretionary Security Policies Mandatory Security Policies Military Security Policies Commercial PoliciesDISTRIBUTED ACCESS CONTROL Digital Authenti

  6. [Ethics in pediatric emergencies: Care access, communication, and confidentiality].

    Science.gov (United States)

    Benoit, J; Berdah, L; Carlier-Gonod, A; Guillou, T; Kouche, C; Patte, M; Schneider, M; Talcone, S; Chappuy, H

    2015-05-01

    Children suffer most from today's increasing precariousness. In France, access to care is available for all children through various structures and existing measures. The support for foreign children is overseen by specific legislation often unfamiliar to caregivers. Pediatric emergencies, their location, organization, actors, and patient flow are a particular environment that is not always suitable to communication and may lead to situations of abuse. Communication should not be forgotten because of the urgency of the situation. The place of the child in the dialogue is often forgotten. Considering the triangular relationship, listening to the child and involving the parents in care are the basis for a good therapeutic alliance. Privacy and medical confidentiality in pediatric emergencies are governed by law. However, changes in treatments and medical practices along with the variety of actors involved imply both individual and collective limitations, to the detriment of medical confidentiality. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  7. Open Access. Chapter 6 of Scholarly Communication for Librarians.

    OpenAIRE

    Morrison, Heather

    2008-01-01

    In-depth overview of open access, covering definitions (open access publishing, open access archives, gratis and libre, open access works versus open access processes), major statements and declarations, types of open access, major initiatives, trends, advocacy and lobbying.

  8. Open Access. Chapter 6 of Scholarly Communication for Librarians.

    OpenAIRE

    Morrison, Heather

    2008-01-01

    In-depth overview of open access, covering definitions (open access publishing, open access archives, gratis and libre, open access works versus open access processes), major statements and declarations, types of open access, major initiatives, trends, advocacy and lobbying.

  9. The Open Access Initiative: A New Paradigm for Scholarly Communications

    Directory of Open Access Journals (Sweden)

    Kristin Yiotis

    2005-12-01

    Full Text Available This paper gives an account of the origin and development of the Open Access Initiative (OAI and the digital technology that enables its existence. The researcher explains the crisis in scholarly communications and how open access (OA can reform the present system. OA has evolved two systems for delivering research articles: OA archives or repositories and OA journals. They differ in that OA journals conduct peer review and OA archives do not. Discussion focuses on how these two delivery systems work, including such topics as OAI, local institutional repositories, Eprints self-archiving software, cross-archives searching, metadata harvesting, and the individuals who invented OA and organizations that support it.

  10. OVERSAMPLED CHAOTIC BINARY SEQUENCES FOR MULTIPLE ACCESS COMMUNICATION

    Institute of Scientific and Technical Information of China (English)

    Zhang Hongtao; Wang Huiyun; Ding Runtao

    2002-01-01

    Noise interference and multiple access interference are the main impairment to the performance of DS/CDMA communication system. This letter presents that OverSampled Chaotic Map (OSCM) binary sequences are secure as spreading sequences, and based on the optimal quantizing method, the BER performance of the system has been derived in detail, the internal relationships among the number of users, the power of noise and the length of code chips are revealed in mathematical formulae. The performance of the system can be improved by employing these formulae. Numerical results conform the efficiency of discussion in this letter.

  11. Integrated optics bus access module for intramachine communication

    Science.gov (United States)

    Karioja, Pentti; Tammela, Simo K. T.; Hannula, Tapio

    1991-12-01

    The feasibility of a passive bidirectional fiber optic bus and the packaging considerations of a bus access module have been studied. The bus uses 110/125 micrometers HCS fiber and passive integrated optic couplers for bus access. The access couplers are asymmetric and were fabricated using a Ag-Na ion exchange process. The asymmetry of the coupler was 5 dB, the launch loss to the bus was 6 dB and the tap-off loss to the node was 11 dB. With the integrated optics coupler it is possible to connect 6 nodes to the bidirectional bus. It is also possible to realize a simple, easy-to-use, and reliable bus access module for intramachine communication. The integrated optics coupler, a LED chip, and a PIN-diode chip and transceiver electronics are packaged in an electrical connector with a two-fiber optical cable pigtail. Active and passive components are butt coupled to the coupler. The 0.5 dB alignment tolerances for the fiber pigtails, the LED, and the PIN-diode chips are +/- 5 micrometers .

  12. Promotion of access to essential medicines for non-communicable diseases : practical implications of the UN political declaration

    NARCIS (Netherlands)

    Hogerzeil, Hans V.; Liberman, Jonathan; Wirtz, Veronika J.; Kishore, Sandeep P.; Selvaraj, Sakthi; Kiddell-Monroe, Rachel; Mwangi-Powell, Faith N.; von Schoen-Angerer, Tido

    2013-01-01

    Access to medicines and vaccines to prevent and treat non-communicable diseases (NCDs) is unacceptably low worldwide. In the 2011 UN political declaration on the prevention and control of NCDs, heads of government made several commitments related to access to essential medicines, technologies, and v

  13. Access Control Based on Trail Inference

    Directory of Open Access Journals (Sweden)

    ALBARELO, P. C.

    2015-06-01

    Full Text Available Professionals are constantly seeking qualification and consequently increasing their knowledge in their area of expertise. Thus, it is interesting to develop a computer system that knows its users and their work history. Using this information, even in the case of professional role change, the system could allow the renewed authorization for activities, based on previously authorized use. This article proposes a model for user access control that is embedded in a context-aware environment. The model applies the concept of trails to manage access control, recording activities usage in contexts and applying this history as a criterion to grant new accesses. Despite the fact that previous related research works consider contexts, none of them uses the concept of trails. Hence, the main contribution of this work is the use of a new access control criterion, namely, the history of previous accesses (trails. A prototype was implemented and applied in an evaluation based on scenarios. The results demonstrate the feasibility of the proposal, allowing for access control systems to use an alternative way to support access rights.

  14. Controlling user access to electronic resources without password

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Fred Hewitt

    2017-08-22

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes obtaining an image from a communication device of a user. An individual and a landmark are identified within the image. Determinations are made that the individual is the user and that the landmark is a predetermined landmark. Access to a restricted computing resource is granted based on the determining that the individual is the user and that the landmark is the predetermined landmark. Other embodiments are disclosed.

  15. A Generic Role Based Access Control Model for Wind Power Systems

    DEFF Research Database (Denmark)

    Nagarajan, Anand; Jensen, Christian D.

    2010-01-01

    infrastructure in a software domain in a manufacturer independent manner as well as establishing secure communication and authenticating the other parties in electrical power infrastructures, but they do not address the problem of access control. We therefore propose a generic model for access control in wind...... power systems, which is based on the widely used role-based access control model. The proposed model is tested using a prototype designed in conformance with the standards that are in use in modern wind power infrastructure and the results are presented to determine the overhead in communication caused...... while adhering to the proposed access model....

  16. Smart Grid Control and Communication

    DEFF Research Database (Denmark)

    Ciontea, Catalin-Iosif; Pedersen, Rasmus; Kristensen, Thomas le Fevre

    2015-01-01

    ) and the quality of the power may become costly. In this light, Smart Grids may provide an answer towards a more active and efficient electrical network. The EU project SmartC2Net aims to enable smart grid operations over imperfect, heterogeneous general purpose networks, which poses a significant challenge...... to the reliability due to the stochastic behavior found in such networks. Therefore, key concepts are presented in this paper targeting the support of proper smart grid control in these network environments and its Real-Time Hardware-In-the Loop (HIL) verification. An overview on the required Information...... and Communication Technology (ICT) architecture and its functionality is provided and a description of a relevant use case that deals with voltage control on medium and low voltage networks along its evaluation approach on an experimental test bed is detailed....

  17. Implementing context and team based access control in healthcare intranets.

    Science.gov (United States)

    Georgiadis, Christos K; Mavridis, Ioannis K; Nikolakopoulou, Georgia; Pangalos, George I

    2002-09-01

    The establishment of an efficient access control system in healthcare intranets is a critical security issue directly related to the protection of patients' privacy. Our C-TMAC (Context and Team-based Access Control) model is an active security access control model that layers dynamic access control concepts on top of RBAC (Role-based) and TMAC (Team-based) access control models. It also extends them in the sense that contextual information concerning collaborative activities is associated with teams of users and user permissions are dynamically filtered during runtime. These features of C-TMAC meet the specific security requirements of healthcare applications. In this paper, an experimental implementation of the C-TMAC model is described. More specifically, we present the operational architecture of the system that is used to implement C-TMAC security components in a healthcare intranet. Based on the technological platform of an Oracle Data Base Management System and Application Server, the application logic is coded with stored PL/SQL procedures that include Dynamic SQL routines for runtime value binding purposes. The resulting active security system adapts to current need-to-know requirements of users during runtime and provides fine-grained permission granularity. Apart from identity certificates for authentication, it uses attribute certificates for communicating critical security metadata, such as role membership and team participation of users.

  18. Towards Communication and Information Access for Deaf People

    Directory of Open Access Journals (Sweden)

    Edwin Blake

    2014-10-01

    Full Text Available In tightly circumscribed communication situations an interactive system resident on a mobile device can assist Deaf people with their communication and information needs. The Deaf users considered here use South African Sign Language and information is conveyed by a collection of pre-recorded video clips and images. The system was developed according to our method of community-based co-design. We present several stages of the development as a series of case studies and highlight our experience. The first stage involved ethnographically inspired methods such as cultural probes. In the next stage we co-designed a medical consultation system that was ultimately dropped for technical reasons. A smaller system was developed for pharmaceutical dispensing and successfully implemented and tested. It now awaits deployment in an actual pharmacy. We also developed a preliminary authoring tool to tackle the problem of content generation for interactive computer literacy training. We are also working on another medical health information tool. We intend that a generic authoring tool be able to generate mobile applications for all of these scenarios. These mobile applications bridge communication gaps for Deaf people via accessible and affordable assistive technology.

  19. Access Agent Improving The Performance Of Access Control Lists

    Directory of Open Access Journals (Sweden)

    Thelis R. S.

    2015-08-01

    Full Text Available The main focus of the proposed research is maintaining the security of a network. Extranet is a popular network among most of the organizations where network access is provided to a selected group of outliers. Limiting access to an extranet can be carried out using Access Control Lists ACLs method. However handling the workload of ACLs is an onerous task for the router. The purpose of the proposed research is to improve the performance and to solidify the security of the ACLs used in a small organization. Using a high performance computer as a dedicated device to share and handle the router workload is suggested in order to increase the performance of the router when handling ACLs. Methods of detecting and directing sensitive data is also discussed in this paper. A framework is provided to help increase the efficiency of the ACLs in an organization network using the above mentioned procedures thus helping the organizations ACLs performance to be improved to be more secure and the system to perform faster. Inbuilt methods of Windows platform or Software for open source platforms can be used to make a computer function as a router. Extended ACL features allow the determining of the type of packets flowing through the router. Combining these mechanisms allows the ACLs to be improved and perform in a more efficient manner.

  20. Cryptographically Enforced Distributed Data Access Control

    NARCIS (Netherlands)

    Ibraimi, L.

    2011-01-01

    Outsourcing data storage reduces the cost of ownership. However, once data is stored on a remote server, users lose control over their sensitive data. There are two approaches to control the access to outsourced data. The first approach assumes that the outsourcee is fully trusted. This approach is

  1. A secure solution on hierarchical access control

    CERN Document Server

    Wei, Chuan-Sheng; Huang, Tone-Yau; Ong, Yao Lin

    2011-01-01

    Hierarchical access control is an important and traditional problem in information security. In 2001, Wu et.al. proposed an elegant solution for hierarchical access control by the secure-filter. Jeng and Wang presented an improvement of Wu et. al.'s method by the ECC cryptosystem. However, secure-filter method is insecure in dynaminc access control. Lie, Hsu and Tripathy, Paul pointed out some secure leaks on the secure-filter and presented some improvements to eliminate these secure flaws. In this paper, we revise the secure-filter in Jeng-Wang method and propose another secure solutions in hierarchical access control problem. CA is a super security class (user) in our proposed method and the secure-filter of $u_i$ in our solutions is a polynomial of degree $n_i+1$ in $\\mathbb{Z}_p^*$, $f_i(x)=(x-h_i)(x-a_1)...(x-a_{n_i})+L_{l_i}(K_i)$. Although the degree of our secure-filter is larger than others solutions, our solution is secure and efficient in dynamics access control.

  2. Spacelab system analysis: The modified free access protocol: An access protocol for communication systems with periodic and Poisson traffic

    Science.gov (United States)

    Ingels, Frank; Owens, John; Daniel, Steven

    1989-01-01

    The protocol definition and terminal hardware for the modified free access protocol, a communications protocol similar to Ethernet, are developed. A MFA protocol simulator and a CSMA/CD math model are also developed. The protocol is tailored to communication systems where the total traffic may be divided into scheduled traffic and Poisson traffic. The scheduled traffic should occur on a periodic basis but may occur after a given event such as a request for data from a large number of stations. The Poisson traffic will include alarms and other random traffic. The purpose of the protocol is to guarantee that scheduled packets will be delivered without collision. This is required in many control and data collection systems. The protocol uses standard Ethernet hardware and software requiring minimum modifications to an existing system. The modification to the protocol only affects the Ethernet transmission privileges and does not effect the Ethernet receiver.

  3. The linked medical data access control framework.

    Science.gov (United States)

    Kamateri, Eleni; Kalampokis, Evangelos; Tambouris, Efthimios; Tarabanis, Konstantinos

    2014-08-01

    The integration of medical data coming from multiple sources is important in clinical research. Amongst others, it enables the discovery of appropriate subjects in patient-oriented research and the identification of innovative results in epidemiological studies. At the same time, the integration of medical data faces significant ethical and legal challenges that impose access constraints. Some of these issues can be addressed by making available aggregated instead of raw record-level data. In many cases however, there is still a need for controlling access even to the resulting aggregated data, e.g., due to data provider's policies. In this paper we present the Linked Medical Data Access Control (LiMDAC) framework that capitalizes on Linked Data technologies to enable controlling access to medical data across distributed sources with diverse access constraints. The LiMDAC framework consists of three Linked Data models, namely the LiMDAC metadata model, the LiMDAC user profile model, and the LiMDAC access policy model. It also includes an architecture that exploits these models. Based on the framework, a proof-of-concept platform is developed and its performance and functionality are evaluated by employing two usage scenarios.

  4. Multihop Medium Access Control for WSNs: An Energy Analysis Model

    Directory of Open Access Journals (Sweden)

    Haapola Jussi

    2005-01-01

    Full Text Available We present an energy analysis technique applicable to medium access control (MAC and multihop communications. Furthermore, the technique's application gives insight on using multihop forwarding instead of single-hop communications. Using the technique, we perform an energy analysis of carrier-sense-multiple-access (CSMA- based MAC protocols with sleeping schemes. Power constraints set by battery operation raise energy efficiency as the prime factor for wireless sensor networks. A detailed energy expenditure analysis of the physical, the link, and the network layers together can provide a basis for developing new energy-efficient wireless sensor networks. The presented technique provides a set of analytical tools for accomplishing this. With those tools, the energy impact of radio, MAC, and topology parameters on the network can be investigated. From the analysis, we extract key parameters of selected MAC protocols and show that some traditional mechanisms, such as binary exponential backoff, have inherent problems.

  5. Access control mechanisms for distributed healthcare environments.

    Science.gov (United States)

    Sergl-Pommerening, Marita

    2004-01-01

    Today's IT-infrastructure provides more and more possibilities to share electronic patient data across several healthcare organizations and hospital departments. A strong requirement is sufficient data protection and security measures complying with the medical confidentiality and the data protection laws of each state or country like the European directive on data protection or the U.S. HIPAA privacy rule. In essence, the access control mechanisms and authorization structures of information systems must be able to realize the Need-To-Access principle. This principle can be understood as a set of context-sensitive access rules, regarding the patient's path across the organizations. The access control mechanisms of today's health information systems do not sufficiently satisfy this requirement, because information about participation of persons or organizations is not available within each system in a distributed environment. This problem could be solved by appropriate security services. The CORBA healthcare domain standard contains such a service for obtaining authorization decisions and administrating access decision policies (RAD). At the university hospital of Mainz we have developed an access control system (MACS), which includes the main functionality of the RAD specification and the access control logic that is needed for such a service. The basic design principles of our approach are role-based authorization, user rights with static and dynamic authorization data, context rules and the separation of three cooperating servers that provide up-to-date knowledge about users, roles and responsibilities. This paper introduces the design principles and the system design and critically evaluates the concepts based on practical experience.

  6. Access Control in Data Management Systems

    CERN Document Server

    Ferrari, Elena

    2010-01-01

    Access control is one of the fundamental services that any Data Management System should provide. Its main goal is to protect data from unauthorized read and write operations. This is particularly crucial in today's open and interconnected world, where each kind of information can be easily made available to a huge user population, and where a damage or misuse of data may have unpredictable consequences that go beyond the boundaries where data reside or have been generated. This book provides an overview of the various developments in access control for data management systems. Discretionary,

  7. Access control mechanism of wireless gateway based on open flow

    Science.gov (United States)

    Peng, Rong; Ding, Lei

    2017-08-01

    In order to realize the access control of wireless gateway and improve the access control of wireless gateway devices, an access control mechanism of SDN architecture which is based on Open vSwitch is proposed. The mechanism utilizes the features of the controller--centralized control and programmable. Controller send access control flow table based on the business logic. Open vSwitch helps achieve a specific access control strategy based on the flow table.

  8. A QUANTUM MULTIPLE ACCESS COMMUNICATIONS SCHEME USING ORBITAL ANGULAR MOMENTUM

    Institute of Scientific and Technical Information of China (English)

    Dong Xiaoliang; Zhao Shengmei; Zheng Baoyu

    2013-01-01

    We propose a quantum multiple access communications scheme using Orbital Angular Momentum (OAM) sector states in the paper.In the scheme,each user has an individual modified Poincare Bloch sphere and encodes his information with his own corresponding sector OAM states.A prepared entangled photon pairs are separated at transmitter and receiver.At the transmitter,each user encodes his information with the sector OAM states on the photons and the superposition of the different sector OAM states is carried by the photons.Then the photons are transmitted through quantum noiseless channel to the receiver.At the receiver,each user could retrieve his information by coincidently measuring the transmitted photons with the receiver side photons which are modulated by a special prepared measurement basis.The theoretical analysis and the numerical simulations show that each user could get his information from the superposition state without error.It seems that this scheme provides a novel method for quantum multiple users communications.

  9. Method for Evaluation of Outage Probability on Random Access Channel in Mobile Communication Systems

    Science.gov (United States)

    Kollár, Martin

    2012-05-01

    In order to access the cell in all mobile communication technologies a so called random-access procedure is used. For example in GSM this is represented by sending the CHANNEL REQUEST message from Mobile Station (MS) to Base Transceiver Station (BTS) which is consequently forwarded as an CHANNEL REQUIRED message to the Base Station Controller (BSC). If the BTS decodes some noise on the Random Access Channel (RACH) as random access by mistake (so- called ‘phantom RACH') then it is a question of pure coincidence which èstablishment cause’ the BTS thinks to have recognized. A typical invalid channel access request or phantom RACH is characterized by an IMMEDIATE ASSIGNMENT procedure (assignment of an SDCCH or TCH) which is not followed by sending an ESTABLISH INDICATION from MS to BTS. In this paper a mathematical model for evaluation of the Power RACH Busy Threshold (RACHBT) in order to guaranty in advance determined outage probability on RACH is described and discussed as well. It focuses on Global System for Mobile Communications (GSM) however the obtained results can be generalized on remaining mobile technologies (ie WCDMA and LTE).

  10. Control of optics in random access analysers

    OpenAIRE

    Truchaud, A.

    1988-01-01

    The technology behind random access analysers involves flexible optical systems which can measure absorbances for one reaction at different scheduled times, and for several reactions performed simultaneously at different wavelengths. Optics control involves light sources (continuous and flash mode), indexing of monochromatic filters, injection-moulded plastic cuvettes, optical fibres, and polychromatic analysis.

  11. Role-based access control in retrospect

    NARCIS (Netherlands)

    Franqueira, Virginia N.L.; Wieringa, Roel

    2012-01-01

    Role-Based Access Control (RBAC) has been a success in terms of the amount of research that went into it, its uptake in international standards, and its adoption by major software vendors. Yet, RBAC remains complex to implement in user organizations. In this paper we review the state of the art of R

  12. Atom-Role-Based Access Control Model

    Science.gov (United States)

    Cai, Weihong; Huang, Richeng; Hou, Xiaoli; Wei, Gang; Xiao, Shui; Chen, Yindong

    Role-based access control (RBAC) model has been widely recognized as an efficient access control model and becomes a hot research topic of information security at present. However, in the large-scale enterprise application environments, the traditional RBAC model based on the role hierarchy has the following deficiencies: Firstly, it is unable to reflect the role relationships in complicated cases effectively, which does not accord with practical applications. Secondly, the senior role unconditionally inherits all permissions of the junior role, thus if a user is under the supervisor role, he may accumulate all permissions, and this easily causes the abuse of permission and violates the least privilege principle, which is one of the main security principles. To deal with these problems, we, after analyzing permission types and role relationships, proposed the concept of atom role and built an atom-role-based access control model, called ATRBAC, by dividing the permission set of each regular role based on inheritance path relationships. Through the application-specific analysis, this model can well meet the access control requirements.

  13. An electronically controlled automatic security access gate

    Directory of Open Access Journals (Sweden)

    Jonathan A. ENOKELA

    2014-11-01

    Full Text Available The security challenges being encountered in many places require electronic means of controlling access to communities, recreational centres, offices, and homes. The electronically controlled automated security access gate being proposed in this work helps to prevent an unwanted access to controlled environments. This is achieved mainly through the use of a Radio Frequency (RF transmitter-receiver pair. In the design a microcontroller is programmed to decode a given sequence of keys that is entered on a keypad and commands a transmitter module to send out this code as signal at a given radio frequency. Upon reception of this RF signal by the receiver module, another microcontroller activates a driver circuitry to operate the gate automatically. The codes for the microcontrollers were written in C language and were debugged and compiled using the KEIL Micro vision 4 integrated development environment. The resultant Hex files were programmed into the memories of the microcontrollers with the aid of a universal programmer. Software simulation was carried out using the Proteus Virtual System Modeling (VSM version 7.7. A scaled-down prototype of the system was built and tested. The electronically controlled automated security access gate can be useful in providing security for homes, organizations, and automobile terminals. The four-character password required to operate the gate gives the system an increased level of security. Due to its standalone nature of operation the system is cheaper to maintain in comparison with a manually operated type.

  14. Access Control from an Intrusion Detection Perspective

    NARCIS (Netherlands)

    Nunes Leal Franqueira, V.

    Access control and intrusion detection are essential components for securing an organization's information assets. In practice, these components are used in isolation, while their fusion would contribute to increase the range and accuracy of both. One approach to accomplish this fusion is the

  15. Communication for command and control systems

    CERN Document Server

    Morris, D J

    1983-01-01

    Communication for Command and Control Systems provides a thorough exposition of the basic theoretical and practical features involved in the design of communication networks for command and control systems. This book focuses primarily on the practical side of computer-controlled communication. This text concentrates on the communication sides of the subject by surveying the means of transferring data between the various processing points and by appraising their potential advantages and possible defects in implementation. In this respect, this book should prove useful for the practicing enginee

  16. Integrating Usage Control with SIP-Based Communications

    Directory of Open Access Journals (Sweden)

    E. Barka

    2008-01-01

    Full Text Available The Session Initiation Protocol (SIP is a signaling protocol used for establishing and maintaining communication sessions involving two or more participants. SIP was initially designed for voice over IP and multimedia conferencing, and then was extended to support other services such as instant messaging and presence management. Today, SIP is also adopted to be used with 3G wireless networks, thus it becomes an integral protocol for ubiquitous environment. SIP has various methods that support a variety of applications such as subscribing to a service, notification of an event, status update, and location and presence services. However, when it comes to security, the use of wireless and mobile communication technologies and the pervasive nature of this environment introduce higher risks to security than that of the old simple environment. In this paper, we introduce new architecture that implements a new type of access control called usage access control (UCON to control the access to the SIP-based communication at preconnection, during connection, and postconnection. This will enable prescribers of SIP services to control who can identify their locations to approve or disapprove their subsequent connections, and to also set some parameters to determine whether a certain communication can continue or should terminate.

  17. VHDL IMPLEMENTATION OF TEST ACCESS PORT CONTROLLER

    Directory of Open Access Journals (Sweden)

    MANPREET KAUR

    2012-06-01

    Full Text Available In this paper, an implementation of IEEE 1149.7 standard is used for designing Test Access Port (TAP Controller and testing of interconnects is done using boundary scan. By c-JTAG the pin count gets reduced which increases the performance and simplifies the connection between devices. TAP Controller is a synchronous Moore type finite state machine that is changed when the TMS and TCK signals of the test access port gets change. This controls the sequence operation of the circuitry conveyed by JTAG and c-JTAG. JTAGmainly used four pins with TAP and fifth pin is for optional use in Boundary scan. But c-JTAG uses only two pins with TAP. In this approach TDI and TDO gets multiplexed by using class T4 and T5 of c-JTAG. Various instructions are used for testing interconnects using IEEE 1149.7 standard (std.

  18. Speed control system for an access gate

    Science.gov (United States)

    Bzorgi, Fariborz M.

    2012-03-20

    An access control apparatus for an access gate. The access gate typically has a rotator that is configured to rotate around a rotator axis at a first variable speed in a forward direction. The access control apparatus may include a transmission that typically has an input element that is operatively connected to the rotator. The input element is generally configured to rotate at an input speed that is proportional to the first variable speed. The transmission typically also has an output element that has an output speed that is higher than the input speed. The input element and the output element may rotate around a common transmission axis. A retardation mechanism may be employed. The retardation mechanism is typically configured to rotate around a retardation mechanism axis. Generally the retardation mechanism is operatively connected to the output element of the transmission and is configured to retard motion of the access gate in the forward direction when the first variable speed is above a control-limit speed. In many embodiments the transmission axis and the retardation mechanism axis are substantially co-axial. Some embodiments include a freewheel/catch mechanism that has an input connection that is operatively connected to the rotator. The input connection may be configured to engage an output connection when the rotator is rotated at the first variable speed in a forward direction and configured for substantially unrestricted rotation when the rotator is rotated in a reverse direction opposite the forward direction. The input element of the transmission is typically operatively connected to the output connection of the freewheel/catch mechanism.

  19. An Enhanced Multiple Random Access Scheme for Satellite Communications

    CERN Document Server

    Bui, Huyen-Chi; Boucheret, Marie-Laure

    2011-01-01

    In this paper, we introduce Multi-Slots Coded ALOHA (MuSCA) as a multiple random access method for satellite communications. This scheme can be considered as a generalization of the Contention Resolution Diversity Slotted Aloha (CRDSA) mechanism. Instead of transmitting replicas, this system replaces them by several parts of a single word of an error correcting code. It is also different from Coded Slotted ALOHA (CSA) as the assumption of destructive collisions is not adopted. In MuSCA, the entity in charge of the decoding mechanism collects all bursts of the same user (including the interfered slots) before decoding and implements a successive interference cancellation (SIC) process to remove successfully decoded signals. Simulations show that for a frame of 100 slots, the achievable total normalized throughput is greater than 1.25 and 1.4 for a frame of 500 slots, resulting in a gain of 80% and 75% with respect to CRDSA and CSA respectively. This paper is a first analysis of the proposed scheme and opens se...

  20. Modelling high data rate communication network access protocol

    Science.gov (United States)

    Khanna, S.; Foudriat, E. C.; Paterra, Frank; Maly, Kurt J.; Overstreet, C. Michael

    1990-01-01

    Modeling of high data rate communication systems is different from the low data rate systems. Three simulations were built during the development phase of Carrier Sensed Multiple Access/Ring Network (CSMA/RN) modeling. The first was a model using SIMCRIPT based upon the determination and processing of each event at each node. The second simulation was developed in C based upon isolating the distinct object that can be identified as the ring, the message, the node, and the set of critical events. The third model further identified the basic network functionality by creating a single object, the node which includes the set of critical events which occur at the node. The ring structure is implicit in the node structure. This model was also built in C. Each model is discussed and their features compared. It should be stated that the language used was mainly selected by the model developer because of his past familiarity. Further the models were not built with the intent to compare either structure or language but because the complexity of the problem and initial results contained obvious errors, so alternative models were built to isolate, determine, and correct programming and modeling errors. The CSMA/RN protocol is discussed in sufficient detail to understand modeling complexities. Each model is described along with its features and problems. The models are compared and concluding observations and remarks are presented.

  1. A Theorem on Grid Access Control

    Institute of Scientific and Technical Information of China (English)

    XU ZhiWei(徐志伟); BU GuanYing(卜冠英)

    2003-01-01

    The current grid security research is mainly focused on the authentication of grid systems. A problem to be solved by grid systems is to ensure consistent access control. This problem is complicated because the hosts in a grid computing environment usually span multiple autonomous administrative domains. This paper presents a grid access control model, based on asynchronous automata theory and the classic Bell-LaPadula model. This model is useful to formally study the confidentiality and integrity problems in a grid computing environment. A theorem is proved, which gives the necessary and sufficient conditions to a grid to maintain confidentiality.These conditions are the formalized descriptions of local (node) relations or relationship between grid subjects and node subjects.

  2. An Access Control Model of Virtual Machine Security

    Directory of Open Access Journals (Sweden)

    QIN Zhong-yuan

    2013-07-01

    Full Text Available Virtualization technology becomes a hot IT technolo gy with the popu-larity of Cloud Computing. However, new security issues arise with it. Specifically, the resources sharing and data communication in virtual machines are most con cerned. In this paper an access control model is proposed which combines the Chinese Wall a nd BLP model. BLP multi-level security model is introduced with corresponding improvement based on PCW (Prioritized Chinese Wall security model. This model can be used to safely co ntrol the resources and event behaviors in virtual machines. Experimental results show its eff ectiveness and safety.

  3. Privacy and Access Control for IHE-Based Systems

    Science.gov (United States)

    Katt, Basel; Breu, Ruth; Hafner, Micahel; Schabetsberger, Thomas; Mair, Richard; Wozak, Florian

    Electronic Health Record (EHR) is the heart element of any e-health system, which aims at improving the quality and efficiency of healthcare through the use of information and communication technologies. The sensitivity of the data contained in the health record poses a great challenge to security. In this paper we propose a security architecture for EHR systems that are conform with IHE profiles. In this architecture we are tackling the problems of access control and privacy. Furthermore, a prototypical implementation of the proposed model is presented.

  4. The Model and Control Methods of Access to Information and Technology Resources of Automated Control Systems in Water Supply Industry

    Science.gov (United States)

    Rytov, M. Yu; Spichyack, S. A.; Fedorov, V. P.; Petreshin, D. I.

    2017-01-01

    The paper describes a formalized control model of access to information and technological resources of automated control systems at water supply enterprises. The given model considers the availability of various communication links with information systems and technological equipment. There are also studied control methods of access to information and technological resources of automated control systems at water supply enterprises. On the basis of the formalized control model and appropriate methods there was developed a software-hardware complex for rapid access to information and technological resources of automated control systems, which contains an administrator’s automated workplace and ultimate users.

  5. Predictive access control for distributed computation

    DEFF Research Database (Denmark)

    Yang, Fan; Hankin, Chris; Nielson, Flemming

    2013-01-01

    We show how to use aspect-oriented programming to separate security and trust issues from the logical design of mobile, distributed systems. The main challenge is how to enforce various types of security policies, in particular predictive access control policies — policies based on the future...... behavior of a program. A novel feature of our approach is that we can define policies concerning secondary use of data....

  6. Communication and control for networked complex systems

    CERN Document Server

    Peng, Chen; Han, Qing-Long

    2015-01-01

    This book reports on the latest advances in the study of Networked Control Systems (NCSs). It highlights novel research concepts on NCSs; the analysis and synthesis of NCSs with special attention to their networked character; self- and event-triggered communication schemes for conserving limited network resources; and communication and control co-design for improving the efficiency of NCSs. The book will be of interest to university researchers, control and network engineers, and graduate students in the control engineering, communication and network sciences interested in learning the core principles, methods, algorithms and applications of NCSs.

  7. An application-layer based centralized information access control for VPN

    Institute of Scientific and Technical Information of China (English)

    OUYANG Kai; ZHOU Jing-li; XIA Tao; YU Sheng-sheng

    2006-01-01

    With the rapid development of Virtual Private Network (VPN), many companies and organizations use VPN to implement their private communication. Traditionally, VPN uses security protocols to protect the confidentiality of data, the message integrity and the endpoint authentication. One core technique of VPN is tunneling, by which clients can access the internal servers traversing VPN. However, the tunneling technique also introduces a concealed security hole. It is possible that ifone vicious user can establish tunneling by the VPN server, he can compromise the internal servers behind the VPN server. So this paper presents a novel Application-layer based Centralized Information Access Control (ACIAC) for VPN to solve this problem.To implement an efficient, flexible and multi-decision access control model, we present two key techniques to ACIAC-the centralized management mechanism and the stream-based access control. Firstly, we implement the information center and the constraints/events center for ACIAC. By the two centers, we can provide an abstract access control mechanism, and the material access control can be decided dynamically by the ACIAC's constraint/event mechanism. Then we logically classify the VPN communication traffic into the access stream and the data stream so that we can tightly couple the features of VPN communication with the access control model. We also provide the design of our ACIAC prototype in this paper.

  8. Identity driven Capability based Access Control (ICAC) Scheme for the Internet of Things

    DEFF Research Database (Denmark)

    Mahalle, Parikshit N.; Anggorojati, Bayu; Prasad, Neeli R.

    2012-01-01

    Internet of Things (IoT) becomes discretionary part of everyday life. Scalability and manageability is daunting due to unbounded number of devices and services. Access control and authorization in IoT with least privilege is equally important to establish secure communication between multiple...... devices and services. In this paper, the concept of capability for access control is introduced where the identities of the involved devices are entrenched in the access capabilities. Identity driven capability based access control (ICAC) scheme presented in this paper helps to alleviate issues related...

  9. Distributed medium access control in wireless networks

    CERN Document Server

    Wang, Ping

    2013-01-01

    This brief investigates distributed medium access control (MAC) with QoS provisioning for both single- and multi-hop wireless networks including wireless local area networks (WLANs), wireless ad hoc networks, and wireless mesh networks. For WLANs, an efficient MAC scheme and a call admission control algorithm are presented to provide guaranteed QoS for voice traffic and, at the same time, increase the voice capacity significantly compared with the current WLAN standard. In addition, a novel token-based scheduling scheme is proposed to provide great flexibility and facility to the network servi

  10. Open Access in the Natural and Social Sciences: The Correspondence of Innovative Moves to Enhance Access, Inclusion and Impact in Scholarly Communication

    Science.gov (United States)

    Armbruster, Chris

    2008-01-01

    Online, open access is the superior model for scholarly communication. A variety of scientific communities in physics, the life sciences and economics have gone furthest in innovating their scholarly communication through open access, enhancing accessibility for scientists, students and the interested public. Open access enjoys a comparative…

  11. Open Access in the Natural and Social Sciences: The Correspondence of Innovative Moves to Enhance Access, Inclusion and Impact in Scholarly Communication

    Science.gov (United States)

    Armbruster, Chris

    2008-01-01

    Online, open access is the superior model for scholarly communication. A variety of scientific communities in physics, the life sciences and economics have gone furthest in innovating their scholarly communication through open access, enhancing accessibility for scientists, students and the interested public. Open access enjoys a comparative…

  12. 7 CFR 1726.176 - Communications and control facilities.

    Science.gov (United States)

    2010-01-01

    ... line carrier communications systems, load control, and supervisory control and data acquisition (SCADA...) Load control systems, communications systems, and SCADA systems—(1) Contract forms. The borrower...

  13. Willingness to Communicate and Action Control

    Science.gov (United States)

    MacIntyre, Peter D.; Doucette, Jesslyn

    2010-01-01

    Being willing to communicate is part of becoming fluent in a second language, which often is the ultimate goal of L2 learners. Julius Kuhl's theory of action control is introduced as an expansion of the conceptual framework for the study of Willingness to Communicate. Kuhl proposed three key concepts, preoccupation, volatility, and hesitation,…

  14. 47 CFR 1.1805 - Federal Communications Commission Section 504 Programs and Activities Accessibility Handbook.

    Science.gov (United States)

    2010-10-01

    ... Programs and Activities Accessibility Handbook. 1.1805 Section 1.1805 Telecommunication FEDERAL... Communications Commission Section 504 Programs and Activities Accessibility Handbook. The Consumer & Governmental... Accessibility Handbook” (“Section 504 Handbook”) for Commission staff, and shall update the Section 504 Handbook...

  15. Authorisation and access control for electronic health record systems.

    Science.gov (United States)

    Blobel, Bernd

    2004-03-31

    Enabling the shared care paradigm, centralised or even decentralised electronic health record (EHR) systems increasingly become core applications in hospital information systems and health networks. For realising multipurpose use and reuse as well as inter-operability at knowledge level, EHR have to meet special architectural requirements. The component-oriented and model-based architecture should meet international standards. Especially in extended health networks realising inter-organisational communication and co-operation, authorisation cannot be organised at user level anymore. Therefore, models, methods and tools must be established to allow formal and structured policy definition, policy agreements, role definition, authorisation and access control. Based on the author's international engagement in EHR architecture and security standards referring to the revision of CEN ENV 13606, the GEHR/open EHR approach, HL7 and CORBA, models for health-specific and EHR-related roles, for authorisation management and access control have been developed. The basic concept is the separation of structural roles defining organisational entity-to-entity relationships and enabling specific acts on the one hand, and functional roles bound to specific activities and realising rights and duties on the other hand. Aggregation of organisational, functional, informational and technological components follows specific rules. Using UML and XML, the principles as well as some examples for analysis, design, implementation and maintenance of policy and authorisation management as well as access control have been practically implemented.

  16. A service-oriented data access control model

    Science.gov (United States)

    Meng, Wei; Li, Fengmin; Pan, Juchen; Song, Song; Bian, Jiali

    2017-01-01

    The development of mobile computing, cloud computing and distributed computing meets the growing individual service needs. Facing with complex application system, it's an urgent problem to ensure real-time, dynamic, and fine-grained data access control. By analyzing common data access control models, on the basis of mandatory access control model, the paper proposes a service-oriented access control model. By regarding system services as subject and data of databases as object, the model defines access levels and access identification of subject and object, and ensures system services securely to access databases.

  17. Perti Net-Based Workflow Access Control Model

    Institute of Scientific and Technical Information of China (English)

    陈卓; 骆婷; 石磊; 洪帆

    2004-01-01

    Access control is an important protection mechanism for information systems. This paper shows how to make access control in workflow system. We give a workflow access control model (WACM) based on several current access control models. The model supports roles assignment and dynamic authorization. The paper defines the workflow using Petri net. It firstly gives the definition and description of the workflow, and then analyzes the architecture of the workflow access control model (WACM). Finally, an example of an e-commerce workflow access control model is discussed in detail.

  18. Controller-independent bidirectional quantum direct communication

    Science.gov (United States)

    Mohapatra, Amit Kumar; Balakrishnan, S.

    2017-06-01

    Recently, Chang et al. (Quantum Inf Process 14:3515-3522, 2015) proposed a controlled bidirectional quantum direct communication protocol using Bell states. In this work, the significance of Bell states, which are being used as initial states in Chang et al. protocol, is elucidated. The possibility of preparing initial state based on the secret message of the communicants is explored. In doing so, the controller-independent bidirectional quantum direct communication protocol has evolved naturally. It is shown that any communicant cannot read the secret message without knowing the initial states generated by the other communicant. Further, intercept-and-resend attack and information leakage can be avoided. The proposed protocol is like a conversion between two persons without the help of any third person with high-level security.

  19. Research of user access control for networked manufacturing system

    Institute of Scientific and Technical Information of China (English)

    ZHENG Xiao-lin; LEI Yu; CHEN De-ren

    2006-01-01

    An integrated user access control method was proposed to address the issues of security and management in networked manufacturing systems (NMS).Based on the analysis of the security issues in networked manufacturing system,an integrated user access control method composed of role-based access control (RBAC),task-based access control (TBAC),relationship-driven access control (RDAC)and coalition-based access control (CBAC) was proposed,including the hierarchical user relationship model,the reference model and the process model.The elements and their relationships were defined,and the expressions of constraints authorization were given.The extensible access control markup language (XACML) was used to implement this method.This method was used in the networked manufacturing system in the Shaoxing spinning region of China.The results show that the integrated user access control method can reduce the costs of system security maintenance and management.

  20. Communication for Inquiry and Access: Teaching Techniques from Discourse Research

    Science.gov (United States)

    Staats, Susan; Duranczyk, Irene; Moore, Randy; Hatch, Jay; Jensen, Murray; Somdahl, Charles

    2006-01-01

    Adopting inquiry-based science and mathematics pedagogies changes traditional classroom communication patterns. Linguistic research in science and mathematics classrooms has identified communication techniques that help teachers manage classroom discussions to increase student interaction and a sense of student responsibility for learning. These…

  1. Access Point Security Service for wireless ad-hoc communication

    NARCIS (Netherlands)

    Scholten, J.; Nijdam, M.

    2006-01-01

    This paper describes the design and implementation of a security solution for ad-hoc peer-to-peer communication. The security solution is based on a scenario where two wireless devices require secure communication, but share no security relationship a priori. The necessary requirements for the secur

  2. Advances in Control and Communication

    CERN Document Server

    2012-01-01

    With success of ICEEE 2010 in Wuhan, China, and December 4 to 5, 2010, the second International Conference of Electrical and Electronics Engineering (ICEEE 2011) will be held in Macau, China, and December 1 to 2, 2011. ICEEE is an annual conference to call together researchers, engineers, academicians as well as industrial professionals from all over the world to present their research results and development activities in Electrical and Electronics Engineering along with Computer Science and Technology, Communication Technology, Artificial Intelligence, Information Technology, etc.   This year ICEEE is sponsored by International Industrial Electronics Center, Hong Kong. And based on the deserved reputation, more than 750 papers have been submitted to ICEEE 2011, from which 92 high quality original papers have been selected for the conference presentation and inclusion in the “Future Information Technology and Computer Engineering” book based on the referees’ comments from peer-refereed.     We expec...

  3. A primer for accessing and using electronic communications technology.

    Science.gov (United States)

    1996-01-01

    This supplement to "The Family Planning Manager" provides basic information for program managers on the equipment, training, and financial resources required to use electronic communications. Boxed sections compare the costs and services of selected communications providers in various countries and present detailed instructions on how to request a document by e-mail. The type of software selected--shell account, store-and-forward connection, or Serial Line Internet Protocol--depends on the type of connection with the communications provider. Among the issues to consider in assessing providers are service costs, telephone charges, equipment costs, modem speed, software, service support, and reputation for good service. Setting up, maintaining, and using electronic communications present new management challenges, especially in terms of providing adequate technical support, training, and funding. The supplement concludes with a glossary of terms commonly used in electronic communications.

  4. Integrating Attributes into Role-Based Access Control

    DEFF Research Database (Denmark)

    Mahmood Rajpoot, Qasim; Jensen, Christian D.; Krishnan, Ram

    2015-01-01

    Role-based access control (RBAC) and attribute-based access control (ABAC) are currently the most prominent access control models. However, they both suffer from limitations and have features complimentary to each other. Due to this fact, integration of RBAC and ABAC has become a hot area...

  5. Attributes Enhanced Role-Based Access Control Model

    DEFF Research Database (Denmark)

    Mahmood Rajpoot, Qasim; Jensen, Christian D.; Krishnan, Ram

    2015-01-01

    as an important area of research. In this paper, we propose an access control model that combines the two models in a novel way in order to unify their benefits. Our approach provides a fine-grained access control mechanism that not only takes contextual information into account while making the access control...

  6. Capability-based Access Control Delegation Model on the Federated IoT Network

    DEFF Research Database (Denmark)

    Anggorojati, Bayu; Mahalle, Parikshit N.; Prasad, Neeli R.

    2012-01-01

    Flexibility is an important property for general access control system and especially in the Internet of Things (IoT), which can be achieved by access or authority delegation. Delegation mechanisms in access control that have been studied until now have been intended mainly for a system that has...... no resource constraint, such as a web-based system, which is not very suitable for a highly pervasive system such as IoT. To this end, this paper presents an access delegation method with security considerations based on Capability-based Context Aware Access Control (CCAAC) model intended for federated...... machine-to-machine communication or IoT networks. The main idea of our proposed model is that the access delegation is realized by means of a capability propagation mechanism, and incorporating the context information as well as secure capability propagation under federated IoT environments. By using...

  7. Break-glass handling exceptional situations in access control

    CERN Document Server

    Petritsch, Helmut

    2014-01-01

    Helmut Petritsch describes the first holistic approach to Break-Glass which covers the whole life-cycle: from access control modeling (pre-access), to logging the security-relevant system state during Break-Glass accesses (at-access), and the automated analysis of Break-Glass accesses (post-access). Break-Glass allows users to override security restrictions in exceptional situations. While several Break-Glass models specific to given access control models have already been discussed in research (e.g., extending RBAC with Break-Glass), the author introduces a generic Break-Glass model. The pres

  8. THE INFLUENCE OF FORMAL COMMUNICATION IN THE PROCESS OF ACCESSING EUROPEAN FUNDS

    Directory of Open Access Journals (Sweden)

    Luminita Zait

    2014-07-01

    Full Text Available Present article aims, based on direct research, to identify of main sources of information in the process of accessing European funds. Performed within Trotus Valley, Bacau, the proposed research provides pertinent information from the perspective of the main sources of influence on the manifestation of interest in accessing funding and in terms of highlighting the influence of various socio-demographic variables on such information sources. According to the Romanian experience of accessing European funds, apparently formal communication efforts prove ineffective, being less reliable and stimulating compared to the informal interpersonal communication. Because most of the potential beneficiaries of EU funds precept this process as one dominated by sinuous and powerful bureaucracy, we tend to believe that in the expressions of interest in accessing EU funds, formal communication only meet the cognitive structure of attitude, affective and conative entering under the influence of informal communication.

  9. Asynchronous Free-Space Optical CDMA Communications System for Last-mile Access Network

    DEFF Research Database (Denmark)

    Jurado-Navas, Antonio; Raddo, Thiago R.; Sanches, Anderson L.

    2016-01-01

    We propose a new hybrid asynchronous OCDMA-FSO communications system for access network solutions. New ABER expressions are derived under gamma-gamma scintillation channels, where all users can surprisingly achieve error-free transmissions when FEC is employed....

  10. Context-Based E-Health System Access Control Mechanism

    Science.gov (United States)

    Al-Neyadi, Fahed; Abawajy, Jemal H.

    E-Health systems logically demand a sufficiently fine-grained authorization policy for access control. The access to medical information should not be just role-based but should also include the contextual condition of the role to access data. In this paper, we present a mechanism to extend the standard role-based access control to incorporate contextual information for making access control decisions in e-health application. We present an architecture consisting of authorisation and context infrastructure that work cooperatively to grant access rights based on context-aware authorization policies and context information.

  11. [Reconceptualising the meaning of scientific communication: open access].

    Science.gov (United States)

    Guédon, Jean-Claude

    2008-01-01

    The recent US law (H.R.2764) affecting NIH policy and the recent unanimous vote by the Arts and Science faculty of Harvard University in favour of a mandatory deposit of researchers' publications in a suitable repository have brought the Open Access movement into public light. After reviewing the historical background of Open Access, its evolution and extension in the United States, Great Britain, France and Canada are examined. Policies aiming at strengthening Open Access to scientific research are viewed as the direct consequence of treating scientific publishing as an integral part of the research cycle. It should, therefore, be wrapped into the financing of research. As the greater part of research is funded by public money, it appears legitimate to make its results as widely available as is possible. Open Access journals and repositories with strong deposit mandates form the backbone of the strategies to achieve the objective of Open Access. Despite the claims of some publishers, Open Access does not weaken or threaten the peer review process, and it does not conflict with copyright laws.

  12. Learners on the Superhighway? Access to Learning via Electronic Communications. Winston Churchill Fellowship Report.

    Science.gov (United States)

    Yeomans, Keith

    Policymakers and practitioners in electronic communication and education in the United States and Canada were interviewed to identify those policies, strategies, and models of good practice used to increase access to learning via electronic communications that are relevant to the United Kingdom and Europe. Information was gathered from 5 experts…

  13. Random Access for Machine-Type Communication based on Bloom Filtering

    DEFF Research Database (Denmark)

    Pratas, Nuno; Stefanovic, Cedomir; Madueño, Germán Corrales

    2016-01-01

    We present a random access method inspired on Bloom filters that is suited for Machine-Type Communications (MTC). Each accessing device sends a signature during the contention process. A signature is constructed using the Bloom filtering method and contains information on the device identity...

  14. The Access to Information and Communication Technologies in the Information Society. The Example of Polish Regions

    OpenAIRE

    Tomaszewska, Anna Wanda

    2013-01-01

    The essay presents the role of information and communication technologies in the information society and different dimensions of the access to ICTs. In the second part, the essay also shows the results of the analysis regarding the ICTs access in Polish regions in the area of households and enterprises.

  15. Access Control in Decentralised Publish/Subscribe Systems

    Directory of Open Access Journals (Sweden)

    Lauri I.W. Pesonen

    2007-04-01

    Full Text Available Publish/subscribe has emerged as an attractive communication paradigm for building Internet-wide distributed systems by decoupling message senders from receivers. Large scale publish/subscribe systems are likely to employ components of the event transport network owned by cooperating, but independent organisations. As the number of participants in the network increases, security becomes an increasing concern. So far most of the research on publish/subscribe has focused on efficient event routing, event filtering, and composite event detection. Very little research has been published regarding securing publish/subscribe systems. This paper extends our previous work to present and evaluate a secure multi-domain publish/subscribe infrastructure that supports and enforces fine-grained access control over the individual attributes of event types.

  16. Rethinking Communicative Language Teaching: A Focus on Access to Fluency

    Science.gov (United States)

    Gatbonton, Elizabeth; Segalowitz, Norman

    2005-01-01

    Although most teachers claim to practise communicative language teaching (CLT), many do not genuinely do so. In this paper, we examine some of the reasons for teachers' resistance to CLT use. We provide a theoretical analysis that focuses on one of the greatest challenges facing CLT methodology-how to promote automatic fluency within this…

  17. Future Computer, Communication, Control and Automation

    CERN Document Server

    2011 International Conference on Computer, Communication, Control and Automation

    2012-01-01

    The volume includes a set of selected papers extended and revised from the 2011 International Conference on Computer, Communication, Control and Automation (3CA 2011). 2011 International Conference on Computer, Communication, Control and Automation (3CA 2011) has been held in Zhuhai, China, November 19-20, 2011. This volume topics covered include wireless communications, advances in wireless video, wireless sensors networking, security in wireless networks, network measurement and management, hybrid and discrete-event systems, internet analytics and automation, robotic system and applications, reconfigurable automation systems, machine vision in automation. We hope that researchers, graduate students and other interested readers benefit scientifically from the proceedings and also find it stimulating in the process.

  18. Cognitive-communication disorder following right hemisphere stroke: exploring rehabilitation access and outcomes.

    Science.gov (United States)

    Hewetson, Ronelle; Cornwell, Petrea; Shum, David

    2017-07-01

    Rehabilitation positively influences return to activities and social roles in people with aphasia. The cognitive-communication disorder (CCD) found following a right hemisphere stroke has been less extensively researched with rehabilitation access and outcomes yet to be determined. To document rehabilitation access and outcomes for people with CCD post-stroke; and compare outcomes based on presence (viz CCD; aphasia) or absence of communication impairment. A retrospective chart audit was completed for patients with first onset unilateral stroke, with a hospital length of stay (LOS) of at least two days and a communication assessment by a speech pathologist. Data extracted included presence and severity of communication impairment, access to and LOS in a rehabilitation unit, and functional outcome measures recorded at rehabilitation discharge. The majority of the 115 patients who met inclusion criteria were living independently (n = 112, 97.4%) at the time of stroke. CCD (66%) was diagnosed with similar frequency to aphasia (68%). The presence of communication impairment did not result in significant differences in rehabilitation LOS and discharge destination when compared to hemispheric strokes without communication impairment. Severity of CCD was an independent predictor of functional gain by rehabilitation discharge. People with CCD require comparable access to rehabilitation as people with aphasia, and severity of CCD should be considered in determining rehabilitation LOS. A large number of people are discharged with ongoing CCD which warrants exploration of potential participation restrictions created by the communication impairment.

  19. Adaptive quality control for multimedia communications

    Directory of Open Access Journals (Sweden)

    Santichai Chuaywong

    2008-01-01

    Full Text Available Multimedia communications are communications with several types of media, such as audio, video and data. The current Internet has some levels of capability to support multimedia communications, unfortunately, the QoS (Quality of Service is still challenging. A large number of QoS mechanisms has been proposed; however, the main concern is for low levels, e.g. layer 2 (Data Link or 3 (Transport. In this paper, mechanisms for control the quality of audio and video are proposed. G.723.1 and MPEG-4 are used as the audio and video codec respectively. The proposed algorithm for adaptive quality control of audio communication is based on forward error correction (FEC. In the case of video communication, the proposed algorithm adapts the value of key frame interval, which is an encoding parameter of MPEG-4. We evaluated our proposed algorithms by computer simulation. We have shown that, in most cases, the proposed scheme gained a higher throughput compared to other schemes.

  20. A multiple access communication network based on adaptive arrays

    Science.gov (United States)

    Zohar, S.

    1981-01-01

    A single frequency communication system is considered consisting of K possibly moving users distributed in space simultaneously communicating with a central station equipped with a computationally adapted array of n = or K antennas. Such a configuration could result if K spacecraft were to be simultaneously tracked by a single DSN complex consisting of an n antennas array. The array employs K sets of n weights to segregate the signals received from the K users. The weights are determined by direct computation based on known position information of the K users. Currently known techniques require (for n = K) about (4/3)K to the 4th power computer operations (multiply and add) to perform such computations. A technique that accomplishes this same goal in 8 K to the 3rd power operations, yielding a reduction by a factor K/6, was developed.

  1. Cognitive Self-Scheduled Mechanism for Access Control in Noisy Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Mario Manzano

    2015-01-01

    Full Text Available Within the challenging environment of intelligent transportation systems (ITS, networked control systems such as platooning guidance of autonomous vehicles require innovative mechanisms to provide real-time communications. Although several proposals are currently under discussion, the design of a rapid, efficient, flexible, and reliable medium access control mechanism which meets the specific constraints of such real-time communications applications remains unsolved in this highly dynamic environment. However, cognitive radio (CR combines the capacity to sense the radio spectrum with the flexibility to adapt to transmission parameters in order to maximize system performance and has thus become an effective approach for the design of dynamic spectrum access (DSA mechanisms. This paper presents the enhanced noncooperative cognitive division multiple access (ENCCMA proposal combining time division multiple access (TDMA and frequency division multiple access (FDMA schemes with CR techniques to obtain a mechanism fulfilling the requirements of real-time communications. The analysis presented here considers the IEEE WAVE and 802.11p as reference standards; however, the proposed medium access control (MAC mechanism can be adapted to operate on the physical layer of different standards. The mechanism also offers the advantage of avoiding signaling, thus enhancing system autonomy as well as behavior in adverse scenarios.

  2. Controlled quantum teleportation and secure direct communication

    Institute of Scientific and Technical Information of China (English)

    Gao Ting; Yan Feng-Li; Wang Zhi-Xi

    2005-01-01

    We present a controlled quantum teleportation protocol. In the protocol, quantum information of an unknown state of a 2-level particle is faithfully transmitted from a sender Alice to a remote receiver Bob via an initially shared triplet of entangled particles under the control of the supervisor Charlie. The distributed entangled particles shared by Alice, Bob and Charlie function as a quantum information channel for faithful transmission. We also propose a controlled and secure direct communication scheme by means of this teleportation. After ensuring the security of the quantum channel, Alice encodes the secret message directly on a sequence of particle states and transmits them to Bob supervised by Charlie using this controlled quantum teleportation. Bob can read out the encoded message directly by the measurement on his qubit. In this scheme, the controlled quantum teleportation transmits Alice's message without revealing any information to a potential eavesdropper. Because there is not a transmission of the qubit carrying the secret message between Alice and Bob in the public channel, it is completely secure for controlled and direct secret communication if perfect quantum channel is used. The special feature of this scheme is that the communication between two sides depends on the agreement of a third side to co-operate.

  3. On the Impact of information access delays on remote control of a wind turbine

    DEFF Research Database (Denmark)

    Madsen, Jacob Theilgaard; Barradas Berglind, Jose de Jesus; Madsen, Tatiana Kozlova;

    2015-01-01

    It is important to reduce the impact of renewable production in the power grid by means of control, due to increased frequency deviations and imbalances caused by these assets. Cost efficient deployment of asset control frequently results in a distributed control architecture where the controller...... is connected via a communication network to the sensors and actuators on the asset. Such a distributed control scheme may be implemented over a communication network that introduces delay and possibly also message loss. In this paper, we look at the impact of such an imperfect communication network on a wind...... by the controller to gather sensor information and and quantitatively characterize the impact of these access strategies on the controller performance...

  4. Recursive estimation algorithms for power controls of wireless communication networks

    Institute of Scientific and Technical Information of China (English)

    Gang George YIN; Chin-An TAN; Le Yi WANG; Chengzhong XU

    2008-01-01

    Power control problems for wireless communication networks are investigated in direct-sequence codedivision multiple-access(DS/CDMA)channels.It is shown that the underlying problem can be formulated as a constrained optimization problem in a stochastic framework.For effective solutions to this optimization problem in real time,recursive algorithms of stochastic approximation type are developed that can solve the problem with unknown system components.Under broad conditions,convergence of the algorithms is established by using weak convergence methods.

  5. Open versus Controlled-Access Data | Office of Cancer Genomics

    Science.gov (United States)

    OCG employs stringent human subjects’ protection and data access policies to protect the privacy and confidentiality of the research participants. Depending on the risk of patient identification, OCG programs data are available to the scientific community in two tiers: open or controlled access. Both types of data can be accessed through its corresponding OCG program-specific data matrix or portal. Open-access Data

  6. Efficient Controlled Quantum Secure Direct Communication Protocols

    OpenAIRE

    Patwardhan, Siddharth; Moulick, Subhayan Roy; Prasanta K. Panigrahi

    2015-01-01

    We study controlled quantum secure direct communication (CQSDC), a cryptographic scheme where a sender can send a secret bit-string to an intended recipient, without any secure classical channel, who can obtain the complete bit-string only with the permission of a controller. We report an efficient protocol to realize CQSDC using Cluster state and then go on to construct a (2-3)-CQSDC using Brown state, where a coalition of any two of the three controllers is required to retrieve the complete...

  7. Policy-based secure communication with automatic key management for industrial control and automation systems

    Science.gov (United States)

    Chernoguzov, Alexander; Markham, Thomas R.; Haridas, Harshal S.

    2016-11-22

    A method includes generating at least one access vector associated with a specified device in an industrial process control and automation system. The specified device has one of multiple device roles. The at least one access vector is generated based on one or more communication policies defining communications between one or more pairs of devices roles in the industrial process control and automation system, where each pair of device roles includes the device role of the specified device. The method also includes providing the at least one access vector to at least one of the specified device and one or more other devices in the industrial process control and automation system in order to control communications to or from the specified device.

  8. Law-Aware Access Control and its Information Model

    CERN Document Server

    Stieghahn, Michael

    2010-01-01

    Cross-border access to a variety of data such as market information, strategic information, or customer-related information defines the daily business of many global companies, including financial institutions. These companies are obliged by law to keep a data processing legal for all offered services. They need to fulfill different security objectives specified by the legislation. Therefore, they control access to prevent unauthorized users from using data. Those security objectives, for example confidentiality or secrecy, are often defined in the eXtensible Access Control Markup Language that promotes interoperability between different systems. In this paper, we show the necessity of incorporating the requirements of legislation into access control. Based on the work flow in a banking scenario we describe a variety of available contextual information and their interrelations. Different from other access control systems our main focus is on law-compliant cross-border data access. By including legislation dir...

  9. Advances in Computer, Communication, Control and Automation

    CERN Document Server

    011 International Conference on Computer, Communication, Control and Automation

    2012-01-01

    The volume includes a set of selected papers extended and revised from the 2011 International Conference on Computer, Communication, Control and Automation (3CA 2011). 2011 International Conference on Computer, Communication, Control and Automation (3CA 2011) has been held in Zhuhai, China, November 19-20, 2011. This volume  topics covered include signal and Image processing, speech and audio Processing, video processing and analysis, artificial intelligence, computing and intelligent systems, machine learning, sensor and neural networks, knowledge discovery and data mining, fuzzy mathematics and Applications, knowledge-based systems, hybrid systems modeling and design, risk analysis and management, system modeling and simulation. We hope that researchers, graduate students and other interested readers benefit scientifically from the proceedings and also find it stimulating in the process.

  10. Research and teaching access to a large clinical picture archiving and communication system

    OpenAIRE

    Harrison, Marc; Koh, Justin; Tran, Steven; Mongkolwat, Patanasak; Channin, David S.

    2001-01-01

    Purpose: To identify practical issues surrounding delivering digital images from picture archiving and communication systems (PACS) for research and teaching purposes. The complexity of Digital Imaging and Communications in Medicine (DICOM) access methods, security, patient confidentiality, PACS database integrity, portability, and scalability are discussed. A software prototype designed to resolve these issues is described.System Architecture: A six-component, three-tier, client server softw...

  11. Code-expanded radio access protocol for machine-to-machine communications

    DEFF Research Database (Denmark)

    Thomsen, Henning; Kiilerich Pratas, Nuno; Stefanovic, Cedomir

    2013-01-01

    The random access methods used for support of machine-to-machine, also referred to as Machine-Type Communications, in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. We propose an approach that is motivated...... subframes and orthogonal preambles, the amount of available contention resources is drastically increased, enabling the massive support of Machine-Type Communication users that is beyond the reach of current systems....

  12. 47 CFR 90.465 - Control of systems of communication.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Control of systems of communication. 90.465... SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control § 90.465 Control of systems of communication. (a) Depending on design considerations, control of a system of communication may be exercised in...

  13. Distributed Role-based Access Control for Coaliagion Application

    Institute of Scientific and Technical Information of China (English)

    HONG Fan; ZHU Xian; XING Guanglin

    2005-01-01

    Access control in multi-domain environments is one of the important questions of building coalition between domains.On the basis of RBAC access control model, the concepts of role delegation and role mapping are proposed, which support the third-party authorization.Then, a distributed RBAC model is presented.Finally the implementation issues are discussed.

  14. 49 CFR 1542.207 - Access control systems.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Access control systems. 1542.207 Section 1542.207..., DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control systems. (a) Secured area. Except as provided in paragraph (b) of this section, the measures...

  15. Privacy Enhanced Access Control by Means of Policy Blinding

    NARCIS (Netherlands)

    Sedghi, Saeed; Hartel, Pieter; Jonker, Willem; Nikova, Svetla; Bao, Feng; Weng, Jian

    2011-01-01

    Traditional techniques of enforcing an access control policy rely on an honest reference monitor to enforce the policy. However, for applications where the resources are sensitive, the access control policy might also be sensitive. As a result, an honest-but-curious reference monitor would glean som

  16. Dynamic User Role Assignment in Remote Access Control

    NARCIS (Netherlands)

    Saffarian, Mohsen; Tang, Qiang; Jonker, Willem; Hartel, Pieter

    2009-01-01

    The Role-Based Access Control (RBAC) model has been widely applied to a single domain in which users are known to the administrative unit of that domain, beforehand. However, the application of the conventional RBAC model for remote access control scenarios is not straightforward. In such scenarios,

  17. Analysis of Access Control Policies in Operating Systems

    Science.gov (United States)

    Chen, Hong

    2009-01-01

    Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the…

  18. Dynamic User Role Assignment in Remote Access Control

    NARCIS (Netherlands)

    Saffarian, M.; Tang, Qiang; Jonker, Willem; Hartel, Pieter H.

    2009-01-01

    The Role-Based Access Control (RBAC) model has been widely applied to a single domain in which users are known to the administrative unit of that domain, beforehand. However, the application of the conventional RBAC model for remote access control scenarios is not straightforward. In such scenarios,

  19. Analysis of Access Control Policies in Operating Systems

    Science.gov (United States)

    Chen, Hong

    2009-01-01

    Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the…

  20. A Model of Workflow-oriented Attributed Based Access Control

    Directory of Open Access Journals (Sweden)

    Guoping Zhang

    2011-02-01

    Full Text Available the emergence of “Internet of Things” breaks previous traditional thinking, which integrates physical infrastructure and network infrastructure into unified infrastructure. There will be a lot of resources or information in IoT, so computing and processing of information is the core supporting of IoT. In this paper, we introduce “Service-Oriented Computing” to solve the problem where each device can offer its functionality as standard services. Here we mainly discuss the access control issue of service-oriented computing in Internet of Things. This paper puts forward a model of Workflow-oriented Attributed Based Access Control (WABAC, and design an access control framework based on WABAC model. The model grants permissions to subjects according to subject atttribute, resource attribute, environment attribute and current task, meeting access control request of SOC. Using the approach presented can effectively enhance the access control security for SOC applications, and prevent the abuse of subject permissions.

  1. Task Delegation Based Access Control Models for Workflow Systems

    Science.gov (United States)

    Gaaloul, Khaled; Charoy, François

    e-Government organisations are facilitated and conducted using workflow management systems. Role-based access control (RBAC) is recognised as an efficient access control model for large organisations. The application of RBAC in workflow systems cannot, however, grant permissions to users dynamically while business processes are being executed. We currently observe a move away from predefined strict workflow modelling towards approaches supporting flexibility on the organisational level. One specific approach is that of task delegation. Task delegation is a mechanism that supports organisational flexibility, and ensures delegation of authority in access control systems. In this paper, we propose a Task-oriented Access Control (TAC) model based on RBAC to address these requirements. We aim to reason about task from organisational perspectives and resources perspectives to analyse and specify authorisation constraints. Moreover, we present a fine grained access control protocol to support delegation based on the TAC model.

  2. Concentration of Access to Information and Communication Technologies in the Municipalities of the Brazilian Legal Amazon.

    Science.gov (United States)

    de Brito, Silvana Rossy; da Silva, Aleksandra do Socorro; Cruz, Adejard Gaia; Monteiro, Maurílio de Abreu; Vijaykumar, Nandamudi Lankalapalli; da Silva, Marcelino Silva; Costa, João Crisóstomo Weyl Albuquerque; Francês, Carlos Renato Lisboa

    2016-01-01

    This study fills demand for data on access and use of information and communication technologies (ICT) in the Brazilian legal Amazon, a region of localities with identical economic, political, and social problems. We use the 2010 Brazilian Demographic Census to compile data on urban and rural households (i) with computers and Internet access, (ii) with mobile phones, and (iii) with fixed phones. To compare the concentration of access to ICT in the municipalities of the Brazilian Amazon with other regions of Brazil, we use a concentration index to quantify the concentration of households in the following classes: with computers and Internet access, with mobile phones, with fixed phones, and no access. These data are analyzed along with municipal indicators on income, education, electricity, and population size. The results show that for urban households, the average concentration in the municipalities of the Amazon for computers and Internet access and for fixed phones is lower than in other regions of the country; meanwhile, that for no access and mobile phones is higher than in any other region. For rural households, the average concentration in the municipalities of the Amazon for computers and Internet access, mobile phones, and fixed phones is lower than in any other region of the country; meanwhile, that for no access is higher than in any other region. In addition, the study shows that education and income are determinants of inequality in accessing ICT in Brazilian municipalities and that the existence of electricity in rural households is directly associated with the ownership of ICT resources.

  3. TRAFFIC CONTROLLED-DEDICATED SHORT RANGE COMMUNICATION: A SECURE COMMUNICATION USING TRAFFIC CONTROLLED DEDICATED SHORT RANGE COMMUNICATION MODEL IN VEHICULAR AD HOC NETWORKS FOR SAFETY RELATED SERVICES

    Directory of Open Access Journals (Sweden)

    K. Chandramohan

    2014-01-01

    Full Text Available To increase the road safety and secure communication among the vehicles in the network environment, Dedicated Short Range Communication (DSRC is followed. Nowadays, research over DSRC is dramatically increased for enhancing the road safety applications. The main task of DSRC is to protect the vehicles by communicating the warning message regarding the vehicle changing conditions, traffic occurrence and dangers over the road in the network. So, it is necessary to maintain the accurate communication timely with high reliability by implementing the appropriate protocol. In the literature there are several methods which provided specifications defined in the physical layer and the Medium Access Control (MAC layer. In those methods, current IEEE 802.11p MAC is not able to provide predictable Quality of Service (QoS for high-priority safety services. Motivated by the fact that the existing work provided three levels of safety-related broadcast services, but did not focus on current traffic load conditions, in this study, we plan to present Traffic Controlled DSRC (TC-DSRC model to analyze and categorize the traffic patterns in the vehicular communication for safety related application. A new algorithm is presented to evaluate the process of traffic controlled DSRC model for secure communication in VANET. The dedicated short range communication broadcast of messages is sent to all the vehicles at a specific instance for defined radius on the traffic zone. Multiple traffic load conditions are categorically stated to handle the vehicular safety with quick response time. Integrating these two performance metrics (i.e., quick response time and security, by using the proposed algorithm, the traffic patterns are categorized for communication between vehicles to provide the safety measure. In addition, our proposed scheme with the categorization using traffic patterns improves the network performance by deriving a specific pattern. Compared with the recent

  4. Layer-component-based communication stack framework for wireless residential control systems

    DEFF Research Database (Denmark)

    Torbensen, R.; Hjorth, Theis S.

    2011-01-01

    of nodes such as bridges, controllers, sensor/actuators – as well as secure communication between them. A special messaging system facilitates inter-component communication, and a Virtual Port Service protocol enables resource addressing. The end-devices in the heterogeneous network are made accessible...... shown how the framework facilitates fast prototyping and makes developing secure wireless control systems less complex.......This paper describes methods to lower the entry barrier for creating products that interoperate in the emerging heterogeneous residential control network domain. For designing reconfigurable, layer-component-based communication stacks, a flexible framework is proposed that supports several types...

  5. Layer-component-based communication stack framework for wireless residential control systems

    DEFF Research Database (Denmark)

    Torbensen, Rune Sonnich; Hjorth, Theis

    2010-01-01

    of nodes such as bridges, controllers, sensor/actuators - as well as secure communication between them. A special messaging system facilitates inter-component communication, and a Virtual Port Service protocol enables resource addressing. The end-devices in the heterogeneous network are made accessible...... shown how the framework facilitates fast prototyping and makes developing secure wireless control systems less complex. © 2010 IEEE.......This paper describes methods to lower the entry barrier for creating products that interoperate in the emerging heterogeneous residential control network domain. For designing reconfigurable, layer-component-based communication stacks, a flexible framework is proposed that supports several types...

  6. Control and estimation methods over communication networks

    CERN Document Server

    Mahmoud, Magdi S

    2014-01-01

    This book provides a rigorous framework in which to study problems in the analysis, stability and design of networked control systems. Four dominant sources of difficulty are considered: packet dropouts, communication bandwidth constraints, parametric uncertainty, and time delays. Past methods and results are reviewed from a contemporary perspective, present trends are examined, and future possibilities proposed. Emphasis is placed on robust and reliable design methods. New control strategies for improving the efficiency of sensor data processing and reducing associated time delay are presented. The coverage provided features: ·        an overall assessment of recent and current fault-tolerant control algorithms; ·        treatment of several issues arising at the junction of control and communications; ·        key concepts followed by their proofs and efficient computational methods for their implementation; and ·        simulation examples (including TrueTime simulations) to...

  7. Code-expanded radio access protocol for machine-to-machine communications

    DEFF Research Database (Denmark)

    Thomsen, Henning; Kiilerich Pratas, Nuno; Stefanovic, Cedomir

    2013-01-01

    The random access methods used for support of machine-to-machine, also referred to as Machine-Type Communications, in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. We propose an approach that is motivated b...

  8. An Ecological Perspective on U.S. Latinos' Health Communication Behaviors, Access, and Outcomes

    Science.gov (United States)

    Katz, Vikki S.; Ang, Alfonso; Suro, Roberto

    2012-01-01

    U.S. Latinos experience constrained access to formal health care resources, contributing to higher incidence of preventable diseases and chronic health conditions than the general population. The authors explore whether a rich set of informal health communication connections--to friends, family, radio, television, Internet, newspapers, magazines,…

  9. Access to Scholarly Communication in Higher Education in India: Trends in Usage Statistics via INFLIBNET

    Science.gov (United States)

    Chand, Prem; Arora, Jagdish

    2008-01-01

    Purpose: The purpose of this paper is to describe the initiative of the University Grants Commission of India in setting up the Infonet Digital Library Consortium (The Information and Library Network) in order to provide access to scholarly communication to the academic community in India. Design/methodology/approach: The context of higher…

  10. Institutional Repositories, Open Access, and Scholarly Communication: A Study of Conflicting Paradigms

    Science.gov (United States)

    Cullen, Rowena; Chawner, Brenda

    2011-01-01

    The Open Access movement of the past decade, and institutional repositories developed by universities and academic libraries as a part of that movement, have openly challenged the traditional scholarly communication system. This article examines the growth of repositories around the world, and summarizes a growing body of evidence of the response…

  11. An Ecological Perspective on U.S. Latinos' Health Communication Behaviors, Access, and Outcomes

    Science.gov (United States)

    Katz, Vikki S.; Ang, Alfonso; Suro, Roberto

    2012-01-01

    U.S. Latinos experience constrained access to formal health care resources, contributing to higher incidence of preventable diseases and chronic health conditions than the general population. The authors explore whether a rich set of informal health communication connections--to friends, family, radio, television, Internet, newspapers, magazines,…

  12. Institutional Repositories, Open Access, and Scholarly Communication: A Study of Conflicting Paradigms

    Science.gov (United States)

    Cullen, Rowena; Chawner, Brenda

    2011-01-01

    The Open Access movement of the past decade, and institutional repositories developed by universities and academic libraries as a part of that movement, have openly challenged the traditional scholarly communication system. This article examines the growth of repositories around the world, and summarizes a growing body of evidence of the response…

  13. The integration of open access journals in the scholarly communication system: Three science fields

    DEFF Research Database (Denmark)

    Faber Frandsen, Tove

    2009-01-01

    The greatest number of open access journals (OAJs) is found in the sciences and their influence is growing. However, there are only a few studies on the acceptance and thereby integration of these OAJs in the scholarly communication system. Even fewer studies provide insight into the differences...

  14. Application of Information and Communication Technology (ICT) in Health Information Access and Dissemination in Uganda

    Science.gov (United States)

    Omona, Walter; Ikoja-Odongo, Robert

    2006-01-01

    This paper reports on a study which assessed the application of information and communication technologies (ICT) in health information access and dissemination in Uganda. The project focused not only on information obtainable through libraries for research, teaching, learning and practice, but also on ICT applications concerned with the…

  15. Application of Information and Communication Technology (ICT) in Health Information Access and Dissemination in Uganda

    Science.gov (United States)

    Omona, Walter; Ikoja-Odongo, Robert

    2006-01-01

    This paper reports on a study which assessed the application of information and communication technologies (ICT) in health information access and dissemination in Uganda. The project focused not only on information obtainable through libraries for research, teaching, learning and practice, but also on ICT applications concerned with the…

  16. Virus spreading in wireless sensor networks with a medium access control mechanism

    Institute of Scientific and Technical Information of China (English)

    Wang Ya-Qi; Yang Xiao-Yuan

    2013-01-01

    In this paper,an extended version of standard susceptible-infected (SI) model is proposed to consider the influence of a medium access control mechanism on virus spreading in wireless sensor networks.Theoretical analysis shows that the medium access control mechanism obviously reduces the density of infected nodes in the networks,which has been ignored in previous studies.It is also found that by increasing the network node density or node communication radius greatly increases the number of infected nodes.The theoretical results are confirmed by numerical simulations.

  17. Network Access Control for Location-Based Mobile Services in Heterogeneous Wireless Networks

    Directory of Open Access Journals (Sweden)

    Dae-Young Kim

    2017-01-01

    Full Text Available Recent advances in information communication technology and software have enabled mobile terminals to employ various capabilities as a smartphone. They adopt multiple interfaces for wireless communication and run as a portable computer. Mobile services are also transferred from voice to data. Mobile terminals can access Internet for data services anytime anywhere. By using location-based information, improved mobile services are enabled in heterogeneous networks. In the mobile service environment, it is required that mobile terminals should efficiently use wireless network resources. In addition, because video stream becomes a major service among the data services of mobile terminals in heterogeneous networks, the necessity of the efficient network access control for heterogeneous wireless networks is raised as an important topic. That is, quality of services of the location-based video stream is determined by the network access control. Therefore, this paper proposes a novel network access control in the heterogeneous wireless networks. The proposed method estimates the network status with Naïve Bayesian Classifier and performs network access control according to the estimated network status. Thus, it improves data transmission efficiency to satisfy the quality of services. The efficiency of the proposed method is validated through the extensive computer simulation.

  18. Design of pulse waveform for waveform division multiple access UWB wireless communication system.

    Science.gov (United States)

    Yin, Zhendong; Wang, Zhirui; Liu, Xiaohui; Wu, Zhilu

    2014-01-01

    A new multiple access scheme, Waveform Division Multiple Access (WDMA) based on the orthogonal wavelet function, is presented. After studying the correlation properties of different categories of single wavelet functions, the one with the best correlation property will be chosen as the foundation for combined waveform. In the communication system, each user is assigned to different combined orthogonal waveform. Demonstrated by simulation, combined waveform is more suitable than single wavelet function to be a communication medium in WDMA system. Due to the excellent orthogonality, the bit error rate (BER) of multiuser with combined waveforms is so close to that of single user in a synchronous system. That is to say, the multiple access interference (MAI) is almost eliminated. Furthermore, even in an asynchronous system without multiuser detection after matched filters, the result is still pretty ideal and satisfactory by using the third combination mode that will be mentioned in the study.

  19. Permission to Speak: A Novel Formal Foundation for Access Control

    Science.gov (United States)

    2016-06-21

    Permission to Speak: A Novel Formal Foundation for Access Control Oleg Sokolsky Nikhil Dinesh, Insup Lee, Aravind Joshi Report Documentation Page...comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE 04 NOV 2009 2. REPORT TYPE 3...DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Permission to Speak: A Novel Formal Foundation for Access Control 5a. CONTRACT

  20. Efficient Controlled Quantum Secure Direct Communication Protocols

    Science.gov (United States)

    Patwardhan, Siddharth; Moulick, Subhayan Roy; Panigrahi, Prasanta K.

    2016-07-01

    We study controlled quantum secure direct communication (CQSDC), a cryptographic scheme where a sender can send a secret bit-string to an intended recipient, without any secure classical channel, who can obtain the complete bit-string only with the permission of a controller. We report an efficient protocol to realize CQSDC using Cluster state and then go on to construct a (2-3)-CQSDC using Brown state, where a coalition of any two of the three controllers is required to retrieve the complete message. We argue both protocols to be unconditionally secure and analyze the efficiency of the protocols to show it to outperform the existing schemes while maintaining the same security specifications.

  1. Access, agency and ambiguity: communication about AIDS among young people in Northern Tanzania.

    Science.gov (United States)

    Bastien, Sheri

    2009-11-01

    Developing interpersonal communication skills is a key component in HIV prevention. Understanding the contexts and content of communication about HIV and AIDS among young people is important for the development of effective programmes and interventions. The aim of this paper is to build on study findings suggesting that significant differences exist between young people in- and out-of-school in exposure to AIDS-related information and communication in Kilimanjaro. In-depth interviews were conducted with young people between the ages of 13 and 18. Data were analyzed using a thematic and comparative approach to explore similarities and differences. A trinity of factors including access, agency and ambiguity emerged as influencing communication about HIV and AIDS. The role of social networks in structuring differences in communication is examined. Findings reveal a discourse laden with fear and mistrust. Coupled with low levels of health literacy, young people regardless of school attendance demonstrate an inability to critically appraise modes of transmission and prevention. An increased emphasis should be placed on the development of critical health literacy and open dialogue. Accessible, unambiguous and culturally relevant interventions built on an understanding of barriers to open communication, which link with community-based initiatives to stimulate dialogue and debate, are needed.

  2. An Extended Role Based Access Control Method for XML Documents

    Institute of Scientific and Technical Information of China (English)

    MENG Xiao-feng; LUO Dao-feng; OU Jian-bo

    2004-01-01

    As XML has been increasingly important as the Data-change format of Internet and Intranet, access-control-on-XML-properties rises as a new issue.Role-based access control (RBAC) is an access control method that has been widely used in Internet, Operation System and Relation Data Base these 10 years.Though RBAC is already relatively mature in the above fields, new problems occur when it is used in XML properties.This paper proposes an integrated model to resolve these problems, after the fully analysis on the features of XML and RBAC.

  3. A new access control system by fingerprint for radioisotope facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Hiroko; Hirata, Yasuki [Kyushu Univ., Fukuoka (Japan). Radioisotope Center; Kondo, Takahiro; Takatsuki, Katsuhiro

    1998-04-01

    We applied a new fingerprint checker for complete access control to the radiation controlled area and to the radioisotope storage room, and prepared softwares for the best use of this checker. This system consists of a personal computer, access controllers, a fingerprint register, fingerprint checkers, a tenkey and mat sensors, permits ten thousand users to register their fingerprints and its hard disk to keep more than a million records of user`s access. Only 1% of users could not register their fingerprints worn-out, registered four numbers for a fingerprint. The softwares automatically provide varieties of reports, caused a large reduction in manual works. (author)

  4. A concurrent access MAC protocol for cognitive radio ad hoc networks without common control channel

    Science.gov (United States)

    Timalsina, Sunil K.; Moh, Sangman; Chung, Ilyong; Kang, Moonsoo

    2013-12-01

    Cognitive radio ad hoc networks (CRAHNs) consist of autonomous nodes that operate in ad hoc mode and aim at efficient utilization of spectrum resources. Usually, the cognitive nodes in a CRAHN exploit a number of available channels, but these channels are not necessarily common to all nodes. Such a network environment poses the problem of establishing a common control channel (CCC) as there might be no channel common to all the network members at all. In designing protocols, therefore, it is highly desirable to consider the network environment with no CCC. In this article, we propose a MAC protocol called concurrent access MAC (CA-MAC) that operates in the network environment with no CCC. The two devices in a communication pair can communicate with each other even if they have only one common channel available. Therefore, the problems with CCC (such as channel saturation and denial of service attacks) can also be resolved. In CA-MAC, channel accesses are distributed over communication pairs, resulting in increased network connectivity. In addition, CA-MAC allows different communication pairs to access multiple channels concurrently. According to our performance study, CA-MAC provides higher network connectivity with shorter channel access delay compared to SYN-MAC, which is the conventional key MAC protocol for the network environment with no CCC, resulting in better network throughput.

  5. Access control management for e-Healthcare in cloud environment

    Directory of Open Access Journals (Sweden)

    Lili Sun

    2014-03-01

    Full Text Available Data outsourcing is a major component for cloud computing that allows data owners to distribute resources to external services for users and organizations who can apply the resources. A crucial problem for owners is how to make sure their sensitive information accessed by legitimate users only using the trusted services but not authorized to read the actual information. With the increased development of cloud computing, it brings challenges for data security and access control when outsourcing users’ data and sharing sensitive data in cloud environment since it is not within the same trusted domain as data owners’. Access control policies have become an important issue in the security filed in cloud computing. Semantic web technologies represent much richer forms of relationships among users, resources and actions among different web applications such as clouding computing. However, Semantic web applications pose new requirements for security mechanisms especially in the access control models. This paper addresses existing access control methods and presents a semantic based access control model which considers semantic relations among different entities in cloud computing environment. We have enriched the research for semantic web technology with role-based access control that is able to be applied in the field of medical information system or e-Healthcare system. This work shows how the semantic web technology provides efficient solutions for the management of complex and distributed data in heterogeneous systems, and it can be used in the medical information systems as well.

  6. Urban Studies: A Study of Bibliographic Access and Control.

    Science.gov (United States)

    Anderson, Barbara E.

    This paper analyzes: (1) the bibliographic access to publications in urban studies via printed secondary sources; (2) development and scope of classification systems and of vocabulary control for urban studies; and (3) currently accessible automated collections of bibliographic citations. Urban studies is defined as "an agglomeration of…

  7. Geospacial information utilized under the access control strategy

    Institute of Scientific and Technical Information of China (English)

    TIAN Jie; ZHANG Xin-fang; WANG Tong-yang; XIANG Wei; Cheng Ming

    2007-01-01

    This paper introduces a solution to the secure requirement for digital rights management (DRM) by the way of geospacial access control named geospacial access control (GeoAC) in geospacial field. The issues of authorization for geospacial DRM are concentrated on. To geospacial DRM, one aspect is the declaration and enforcement of access rights, based on geographic aspects. To the approbation of digital geographic content, it is important to adopt online access to geodata through a spacial data infrastructure (SDI). This results in the interoperability requirements on three different levels: data model level, service level and access control level. The interaction between the data model and service level can be obtained by criterions of the open geospacial consortium (OGC), and the interaction of the access control level may be reached by declaring and enforcing access restrictions in GeoAC. Then an archetype enforcement based on GeoAC is elucidated. As one aspect of performing usage rights, the execution of access restrictions as an extension to a regular SDI is illuminated.

  8. Tuberculosis comorbidity with communicable and non-communicable diseases: integrating health services and control efforts.

    OpenAIRE

    Marais, BJ; Lönnroth, K.; Lawn, SD; Migliori, GB; Mwaba, P.; Glaziou, P; Bates, M; Colagiuri, R; Zijenah, L; Swaminathan, S; Memish, ZA; Pletschette, M; Hoelscher, M; Abubakar, I; Hasan, R.

    2013-01-01

    Recent data for the global burden of disease reflect major demographic and lifestyle changes, leading to a rise in non-communicable diseases. Most countries with high levels of tuberculosis face a large comorbidity burden from both non-communicable and communicable diseases. Traditional disease-specific approaches typically fail to recognise common features and potential synergies in integration of care, management, and control of non-communicable and communicable diseases. In resource-limite...

  9. A New Signaling Architecture THREP with Autonomous Radio-Link Control for Wireless Communications Systems

    Science.gov (United States)

    Hirono, Masahiko; Nojima, Toshio

    This paper presents a new signaling architecture for radio-access control in wireless communications systems. Called THREP (for THREe-phase link set-up Process), it enables systems with low-cost configurations to provide tetherless access and wide-ranging mobility by using autonomous radio-link controls for fast cell searching and distributed call management. A signaling architecture generally consists of a radio-access part and a service-entity-access part. In THREP, the latter part is divided into two steps: preparing a communication channel, and sustaining it. Access control in THREP is thus composed of three separated parts, or protocol phases. The specifications of each phase are determined independently according to system requirements. In the proposed architecture, the first phase uses autonomous radio-link control because we want to construct low-power indoor wireless communications systems. Evaluation of channel usage efficiency and hand-over loss probability in the personal handy-phone system (PHS) shows that THREP makes the radio-access sub-system operations in a practical application model highly efficient, and the results of a field experiment show that THREP provides sufficient protection against severe fast CNR degradation in practical indoor propagation environments.

  10. Layer-component-based communication stack framework for wireless residential control systems

    DEFF Research Database (Denmark)

    Torbensen, R.; Hjorth, Theis S.

    2011-01-01

    This paper describes methods to lower the entry barrier for creating products that interoperate in the emerging heterogeneous residential control network domain. For designing reconfigurable, layer-component-based communication stacks, a flexible framework is proposed that supports several types...... of nodes such as bridges, controllers, sensor/actuators – as well as secure communication between them. A special messaging system facilitates inter-component communication, and a Virtual Port Service protocol enables resource addressing. The end-devices in the heterogeneous network are made accessible...

  11. Access Control of Web- and Java-Based Applications

    Science.gov (United States)

    Tso, Kam S.; Pajevski, Michael J.

    2013-01-01

    Cybersecurity has become a great concern as threats of service interruption, unauthorized access, stealing and altering of information, and spreading of viruses have become more prevalent and serious. Application layer access control of applications is a critical component in the overall security solution that also includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. An access control solution, based on an open-source access manager augmented with custom software components, was developed to provide protection to both Web-based and Javabased client and server applications. The DISA Security Service (DISA-SS) provides common access control capabilities for AMMOS software applications through a set of application programming interfaces (APIs) and network- accessible security services for authentication, single sign-on, authorization checking, and authorization policy management. The OpenAM access management technology designed for Web applications can be extended to meet the needs of Java thick clients and stand alone servers that are commonly used in the JPL AMMOS environment. The DISA-SS reusable components have greatly reduced the effort for each AMMOS subsystem to develop its own access control strategy. The novelty of this work is that it leverages an open-source access management product that was designed for Webbased applications to provide access control for Java thick clients and Java standalone servers. Thick clients and standalone servers are still commonly used in businesses and government, especially for applications that require rich graphical user interfaces and high-performance visualization that cannot be met by thin clients running on Web browsers

  12. Modeling Access Control Policy of a Social Network

    Directory of Open Access Journals (Sweden)

    Chaimaa Belbergui

    2016-06-01

    Full Text Available Social networks bring together users in a virtual platform and offer them the ability to share -within the Community- personal and professional information’s, photos, etc. which are sometimes sensitive. Although, the majority of these networks provide access control mechanisms to their users (to manage who accesses to which information, privacy settings are limited and do not respond to all users' needs. Hence, the published information remain all vulnerable to illegal access. In this paper, the access control policy of the social network "Facebook" is analyzed in a profound way by starting with its modeling with "Organization Role Based Access Control" model, and moving to the simulation of the policy with an appropriate simulator to test the coherence aspect, and ending with a discussion of analysis results which shows the gap between access control management options offered by Facebook and the real requirements of users in the same context. Extracted conclusions prove the need of developing a new access control model that meets most of these requirements, which will be the subject of a forthcoming work.

  13. 1st International Conference on Intelligent Communication, Control and Devices

    CERN Document Server

    Choudhury, Sushabhan

    2017-01-01

    The book presents high-quality research papers presented at the first international conference, ICICCD 2016, organised by the Department of Electronics, Instrumentation and Control Engineering of University of Petroleum and Energy Studies, Dehradun on 2nd and 3rd April, 2016. The book is broadly divided into three sections: Intelligent Communication, Intelligent Control and Intelligent Devices. The areas covered under these sections are wireless communication and radio technologies, optical communication, communication hardware evolution, machine-to-machine communication networks, routing techniques, network analytics, network applications and services, satellite and space communications, technologies for e-communication, wireless Ad-Hoc and sensor networks, communications and information security, signal processing for communications, communication software, microwave informatics, robotics and automation, optimization techniques and algorithms, intelligent transport, mechatronics system, guidance and navigat...

  14. On Novel Access and Scheduling Schemes for IoT Communications

    Directory of Open Access Journals (Sweden)

    Zheng Jiang

    2016-01-01

    Full Text Available The Internet of Things (IoT is expected to foster the development of 5G wireless networks and requires the efficient support for a large number of simultaneous short message communications. To address these challenges, some existing works utilize new waveform and multiuser superposition transmission schemes to improve the capacity of IoT communication. In this paper, we will investigate the spatial degree of freedom of IoT devices based on their distribution, then extend the multiuser shared access (MUSA which is one of the typical MUST schemes to spatial domain, and propose two novel schemes, that is, the preconfigured access scheme and the joint spatial and code domain scheduling scheme, to enhance IoT communication. The results indicate that the proposed schemes can reduce the collision rate dramatically during the IoT random access procedure and improve the performance of IoT communication obviously. Based on the simulation results, it is also shown that the proposed scheduling scheme can achieve the similar performance to the corresponding brute-force scheduling but with lower complexity.

  15. Personnel Access Control System Evaluation for National Ignition Facility Operations

    Energy Technology Data Exchange (ETDEWEB)

    Altenbach, T; Brereton, S.; Hermes, G.; Singh, M.

    2001-06-01

    The purpose of this document is to analyze the baseline Access Control System for the National Ignition Facility (NIF), and to assess its effectiveness at controlling access to hazardous locations during full NIF operations. It reviews the various hazards present during a NIF shot sequence, and evaluates the effectiveness of the applicable set of controls at preventing access while the hazards are present. It considers only those hazards that could potentially be lethal. In addition, various types of technologies that might be applicable at NIF are reviewed, as are systems currently in use at other facilities requiring access control for safety reasons. Recommendations on how this system might be modified to reduce risk are made.

  16. Experience with ActiveX control for simple channel access

    Energy Technology Data Exchange (ETDEWEB)

    Timossi, C.; Nishimura, H.; McDonald, J.

    2003-05-15

    Accelerator control system applications at Berkeley Lab's Advanced Light Source (ALS) are typically deployed on operator consoles running Microsoft Windows 2000 and utilize EPICS[2]channel access for data access. In an effort to accommodate the wide variety of Windows based development tools and developers with little experience in network programming, ActiveX controls have been deployed on the operator stations. Use of ActiveX controls for use in the accelerator control environment has been presented previously[1]. Here we report on some of our experiences with the use and development of these controls.

  17. Identity Establishment and Capability Based Access Control (IECAC) Scheme for Internet of Things

    DEFF Research Database (Denmark)

    Mahalle, Parikshit N.; Anggorojati, Bayu; Prasad, Neeli R.

    2012-01-01

    and denial of service attacks, the concept of capability for access control is introduced. This paper presents Identity establishment and capability based access control (IECAC) protocol using ECC (Elliptical Curve Cryptography) for IoT along with protocol evaluation, which protect against the aforementioned......Internet of Things (IoT) become discretionary part of everyday life and could befall a threat if security is not considered before deployment. Authentication and access control in IoT is equally important to establish secure communication between devices. To protect IoT from man in middle, replay...... attacks. The protocol evaluation by using security protocol verification tool shows that IECAC is secure against these attacks. This paper also discusses performance analysis of the protocol in terms of computational time and compared with other existing solutions....

  18. A Novel Digital Certificate Based Remote Data Access Control Scheme in WSN

    Directory of Open Access Journals (Sweden)

    Wei Liang

    2015-01-01

    Full Text Available A digital certificate based remote data access control scheme is proposed for safe authentication of accessor in wireless sensor network (WSN. The scheme is founded on the access control scheme on the basis of characteristic expression (named CEB scheme. Data is divided by characteristics and the key for encryption is related to characteristic expression. Only the key matching with characteristic expression can decrypt the data. Meanwhile, three distributed certificate detection methods are designed to prevent the certificate from being misappropriated by hostile anonymous users. When a user starts query, the key access control method can judge whether the query is valid. In this case, the scheme can achieve public certificate of users and effectively protect query privacy as well. The security analysis and experiments show that the proposed scheme is superior in communication overhead, storage overhead, and detection probability.

  19. Distributed Access Control Based on Proxy Signature in M2M Sensor Networks

    Directory of Open Access Journals (Sweden)

    Lingyu Lee

    2013-05-01

    Full Text Available In this study, we have a research of the distributed access control based on proxy signature in M2M sensor networks M2M sensor networks. As M2M sensor networks are usually deployed in hostile environment, the global communication security of M2M sensor networks is and will continue to be a major concern. Although there are many related works on access control in WSNs (Wireless Sensor Networks, Ad-hoc networks, MANETs (Mobile Ad-hoc Networks and etc., they cannot be applied to M2M sensor networks directly. Motivated by this consideration, we develop a secure and distributed access control scheme based on proxy signature for M2M sensor networks, which provides strong authentication and achieves efficiency. Moreover, security of the proposed technique does not rely on availability of a secure channel.

  20. Testing Efficiency Improved by Addition of Remote Access Control Room

    Science.gov (United States)

    1996-01-01

    The NASA Lewis Research Center's Remote Access Control Room (RACR) uses off-the-shelf video conferencing software integrated with existing facility data systems to provide access to the test data by networking from virtually anywhere in the country. The system allows research engineers in remote locations to participate in tests and monitor data in real time just as if they were present in the control room.

  1. State of the Art Authentication, Access Control, and Secure Integration in Smart Grid

    Directory of Open Access Journals (Sweden)

    Neetesh Saxena

    2015-10-01

    Full Text Available The smart grid (SG is a promising platform for providing more reliable, efficient, and cost effective electricity to the consumers in a secure manner. Numerous initiatives across the globe are taken by both industry and academia in order to compile various security issues in the smart grid network. Unfortunately, there is no impactful survey paper available in the literature on authentications in the smart grid network. Therefore, this paper addresses the required objectives of an authentication protocol in the smart grid network along with the focus on mutual authentication, access control, and secure integration among different SG components. We review the existing authentication protocols, and analyze mutual authentication, privacy, trust, integrity, and confidentiality of communicating information in the smart grid network. We review authentications between the communicated entities in the smart grid, such as smart appliance, smart meter, energy provider, control center (CC, and home/building/neighborhood area network gateways (GW. We also review the existing authentication schemes for the vehicle-to-grid (V2G communication network along with various available secure integration and access control schemes. We also discuss the importance of the mutual authentication among SG entities while providing confidentiality and privacy preservation, seamless integration, and required access control with lower overhead, cost, and delay. This paper will help to provide a better understanding of current authentication, authorization, and secure integration issues in the smart grid network and directions to create interest among researchers to further explore these promising areas.

  2. Dynamically Authorized Role-Based Access Control for Grid Applications

    Institute of Scientific and Technical Information of China (English)

    YAO Hanbing; HU Heping; LU Zhengding; LI Ruixuan

    2006-01-01

    Grid computing is concerned with the sharing and coordinated use of diverse resources in distributed "virtual organizations". The heterogeneous, dynamic and multi-domain nature of these environments makes challenging security issues that demand new technical approaches. Despite the recent advances in access control approaches applicable to Grid computing, there remain issues that impede the development of effective access control models for Grid applications. Among them there are the lack of context-based models for access control, and reliance on identity or capability-based access control schemes. An access control scheme that resolve these issues is presented, and a dynamically authorized role-based access control (D-RBAC) model extending the RBAC with context constraints is proposed. The D-RABC mechanisms dynamically grant permissions to users based on a set of contextual information collected from the system and user's environments, while retaining the advantages of RBAC model. The implementation architecture of D-RBAC for the Grid application is also described.

  3. A mobile console for local access to accelerator control systems.

    CERN Multimedia

    1981-01-01

    Microprocessors were installed as auxiliary crate controllers (ACCs) in the CAMAC interface of control systems for various accelerators. The same ACC was also at the hearth of a stand-alone system in the form of a mobile console. This was also used for local access to the control systems for tests and development work (Annual Report 1981, p. 80, Fig. 10).

  4. Impact of the information age on residency training: communication, access to public information, and clinical care.

    Science.gov (United States)

    Hilty, Donald M; Belitsky, Richard; Cohen, Mitchell B; Cabaniss, Deborah L; Dickstein, Leah J; Bernstein, Carol A; Kaplan, Allan S; Scheiber, Stephen C; Crisp-Han, Holly D; Wrzosek, Marika I; Silberman, Edward K

    2015-02-01

    Access to technology in practice helps physicians manage information, communicate, and research topics; however, those in training receive almost no formal preparation for integrating web-based technologies into practice. One reason for this is that many faculty-aside from junior faculty or those in recent generations-did not grow up using Internet communication, may use it minimally, if at all, in their own practices, and may know little about its forms and varieties. This report presents a case to illustrate how these disparities may play out in the supervisory situation and makes suggestions about helping supervisors integrate technology-awareness into their teaching.

  5. DO INFORMATION AND COMMUNICATION TECHNOLOGY ACCESS AND INNOVATION INCREASE OUTSOURCING IN SMALL AND MEDIUM ENTERPRISES?

    Directory of Open Access Journals (Sweden)

    María Verónica Alderete

    2013-08-01

    Full Text Available In this paper we present an econometric model to determine whether an SME (Small and Medium Sized Enterprise’s probability of outsourcing depends on their levels of innovation and information and communication technology use. The predictions of the econometric model are tested by means of a LOGIT model using a cross section sample of an Argentinean SME for the year 2006. The model predicts that the level of innovation of an SME will significantly influence its probability of outsourcing. Besides, it stresses the negative incidence of the information and communication technologies (ICT access on the outsourcing decision.

  6. Remote device access in the new accelerator controls middleware

    CERN Document Server

    Baggiolini, V; Jensen, S; Kostro, K; Risso, A; Trofimov, N N; SL

    2001-01-01

    This paper presents the Remote Device Access (RDA) package developed at CERN in the framework of the joint PS/SL Controls Middleware project. The package design reflects the Accelerator Device Model in which devices, named entities in the control system, can be controlled via properties. RDA implements this model in a distributed environment with devices residing in servers that can run anywhere in the controls network. It provides a location-independent and reliable access to the devices from control programs. By invoking the device access methods, clients can read, write and subscribe to device property values. We describe the architecture and design of RDA its API, and CORBA-based implementations in Java and C++. First applications of RDA in the CERN accelerator control systems are described as well.

  7. A Survey of Downlink Non-Orthogonal Multiple Access for 5G Wireless Communication Networks

    Institute of Scientific and Technical Information of China (English)

    WEI Zhiqiang; YUAN Jinhong; Derrick Wing Kwan Ng; Maged Elkashlan; DING Zhiguo

    2016-01-01

    Non⁃orthogonal multiple access (NOMA) has been recognized as a promising multiple access technique for the next generation cel⁃lular communication networks. In this paper, we first discuss a simple NOMA model with two users served by a single⁃carrier si⁃multaneously to illustrate its basic principles. Then, a more general model with multicarrier serving an arbitrary number of users on each subcarrier is also discussed. An overview of existing works on performance analysis, resource allocation, and multiple⁃in⁃put multiple⁃output NOMA are summarized and discussed. Furthermore, we discuss the key features of NOMA and its potential re⁃search challenges.

  8. Low-sampling-rate M-ary multiple access UWB communications in multipath channels

    KAUST Repository

    Alkhodary, Mohammad T.

    2015-08-31

    The desirable characteristics of ultra-wideband (UWB) technology are challenged by formidable sampling frequency, performance degradation in the presence of multi-user interference, and complexity of the receiver due to the channel estimation process. In this paper, a low-rate-sampling technique is used to implement M-ary multiple access UWB communications, in both the detection and channel estimation stages. A novel approach is used for multiple-access-interference (MAI) cancelation for the purpose of channel estimation. Results show reasonable performance of the proposed receiver for different number of users operating many times below Nyquist rate.

  9. Concentration of Access to Information and Communication Technologies in the Municipalities of the Brazilian Legal Amazon.

    Directory of Open Access Journals (Sweden)

    Silvana Rossy de Brito

    Full Text Available This study fills demand for data on access and use of information and communication technologies (ICT in the Brazilian legal Amazon, a region of localities with identical economic, political, and social problems. We use the 2010 Brazilian Demographic Census to compile data on urban and rural households (i with computers and Internet access, (ii with mobile phones, and (iii with fixed phones. To compare the concentration of access to ICT in the municipalities of the Brazilian Amazon with other regions of Brazil, we use a concentration index to quantify the concentration of households in the following classes: with computers and Internet access, with mobile phones, with fixed phones, and no access. These data are analyzed along with municipal indicators on income, education, electricity, and population size. The results show that for urban households, the average concentration in the municipalities of the Amazon for computers and Internet access and for fixed phones is lower than in other regions of the country; meanwhile, that for no access and mobile phones is higher than in any other region. For rural households, the average concentration in the municipalities of the Amazon for computers and Internet access, mobile phones, and fixed phones is lower than in any other region of the country; meanwhile, that for no access is higher than in any other region. In addition, the study shows that education and income are determinants of inequality in accessing ICT in Brazilian municipalities and that the existence of electricity in rural households is directly associated with the ownership of ICT resources.

  10. Retaking Responsibility for How We Communicate. A Review of Open Access and the Humanities: Contexts, Controversies and the Future

    Directory of Open Access Journals (Sweden)

    James Baker

    2015-06-01

    Full Text Available Since the publication of the Budapest Open Access Initiative statement in 2002, Open Access has grown from an ideal to a reality. Open Access and the Humanities explores scholarly practices, communications, and cultures in light of this change and argues that humanists can and should retake responsibility for how they chose to publish.

  11. Communication and Control in the Canadian North: The Role of Interactive Satellites.

    Science.gov (United States)

    Valaskakis, Gail G.

    In 1972 the Canadian government launched its first domestic communications satellite, Anik A, which relays direct broadcast television and telephone messages to northern communities. The impact of television on Inuit life has raised issues and concerns pertaining to native language broadcasting, media access and control, and cultural identity…

  12. Optimum feedback strategy for access control mechanism modelled as stochastic differential equation in computer network

    Directory of Open Access Journals (Sweden)

    Ahmed N. U.

    2004-01-01

    Full Text Available We consider optimum feedback control strategy for computer communication network, in particular, the access control mechanism. The dynamic model representing the source and the access control system is described by a system of stochastic differential equations developed in our previous works. Simulated annealing (SA was used to optimize the parameters of the control law based on neural network. This technique was found to be computationally intensive. In this paper, we have proposed to use a more powerful algorithm known as recursive random search (RRS. By using this technique, we have been able to reduce the computation time by a factor of five without compromising the optimality. This is very important for optimization of high-dimensional systems serving a large number of aggregate users. The results show that the proposed control law can improve the network performance by improving throughput, reducing multiplexor and TB losses, and relaxing, not avoiding, congestion.

  13. Error correction coding for frequency-hopping multiple-access spread spectrum communication systems

    Science.gov (United States)

    Healy, T. J.

    1982-01-01

    A communication system which would effect channel coding for frequency-hopped multiple-access is described. It is shown that in theory coding can increase the spectrum utilization efficiency of a system with mutual interference to 100 percent. Various coding strategies are discussed and some initial comparisons are given. Some of the problems associated with implementing the type of system described here are discussed.

  14. Transparent image access in a distributed picture archiving and communications system: The master database broker

    OpenAIRE

    Cox, R D; Henri, C. J.; Rubin, R. K.

    1999-01-01

    A distributed design is the most cost-effective system for small- to medium-scale picture archiving and communications systems (PACS) implementations. However, the design presents an interesting challenge to developers and implementers: to make stored image data, distributed throughout the PACS network, appear to be centralized with a single access point for users. A key component for the distributed system is a central or master database, containing all the studies that have been scanned int...

  15. Polarization division multiple access with polarization modulation for LOS wireless communications

    Directory of Open Access Journals (Sweden)

    Cao Bin

    2011-01-01

    Full Text Available Abstract In this paper, we discuss a potential multiple access and modulation scheme based on polarized states (PS of electromagnetic (EM waves for line-of-sight (LOS communications. The proposed scheme is theoretic different from the existing polar modulation for EDGE and WCDMA systems. We propose the detailed bit representation (modulation and multiple access scheme using PS. Because of the inflexibility of polarization information in the time and frequency domains, as well as independence of frequency and space, the polarization information can be used independently for wireless communications, i.e., another independent resource domain that can be utilized. Due to the independence between the PS and the specific features of signals (such as waveform, bandwidth and data rate, the discussed polarization division multiple access (PDMA and polarization modulation (PM are expected to improve the spectrum utilization effectively. It is proved that the polarization filtering technique can be adopted in the PDMA-PM wireless communications to separate the multiuser signals and demodulate the bit information representing by PS for desired user. Some theoretical analysis is done to demonstrate the feasibility of the proposed scheme, and the simulation results are made to evaluate the performance of the suggested system.

  16. Access to Communication for Deaf, Hard-of-Hearing and ESL Students in Blended Learning Courses

    Directory of Open Access Journals (Sweden)

    Gary L. Long

    2007-11-01

    Full Text Available In an effort to better understand student perceptions of communication in blended (online and traditional learning courses, a 22 item questionnaire was developed and sent to all students registered for these courses at a large technology-focused college during three quarters of instruction. The respondents were divided into four groups: 1 hearing, 2 deaf, 3 hard-of-hearing (D/HH, and 3 English as a second language (ESL. Their perceptions of communication and the blended learning experience were examined. While the hearing and ESL students were positive about blended learning, the findings indicated that deaf and hard-of-hearing students reported that both the quality and quantity of their interactions with the professor and other students was greatly improved by the inclusion of an online component. ESL and hearing students were also positive about the blended experience; but the greatest benefit to communication access was observed by students with a hearing loss.

  17. CSchema: A Downgrading Policy Language for XML Access Control

    Institute of Scientific and Technical Information of China (English)

    Dong-Xi Liu

    2007-01-01

    The problem of regulating access to XML documents has attracted much attention from both academic and industry communities.In existing approaches, the XML elements specified by access policies are either accessible or inac-cessible according to their sensitivity.However, in some cases, the original XML elements are sensitive and inaccessible, but after being processed in some appropriate ways, the results become insensitive and thus accessible.This paper proposes a policy language to accommodate such cases, which can express the downgrading operations on sensitive data in XML documents through explicit calculations on them.The proposed policy language is called calculation-embedded schema (CSchema), which extends the ordinary schema languages with protection type for protecting sensitive data and specifying downgrading operations.CSchema language has a type system to guarantee the type correctness of the embedded calcula-tion expressions and moreover this type system also generates a security view after type checking a CSchema policy.Access policies specified by CSchema are enforced by a validation procedure, which produces the released documents containing only the accessible data by validating the protected documents against CSchema policies.These released documents are then ready tobe accessed by, for instance, XML query engines.By incorporating this validation procedure, other XML processing technologies can use CSchema as the access control module.

  18. A Tractable Model of the LTE Access Reservation Procedure for Machine-Type Communications

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Min Kim, Dong; Madueño, Germán Corrales;

    2015-01-01

    A canonical scenario in Machine-Type Communications (MTC) is the one featuring a large number of devices, each of them with sporadic traffic. Hence, the number of served devices in a single LTE cell is not determined by the available aggregate rate, but rather by the limitations of the LTE access...... reservation protocol. Specifically, the limited number of contention preambles and the limited amount of uplink grants per random access response are crucial to consider when dimensioning LTE networks for MTC. We propose a low-complexity model that encompasses these two limitations and allows us to evaluate...... on the preamble collisions. A comparison with the simulated LTE access reservation procedure that follows the 3GPP specifications, confirms that our model provides an accurate estimation of the system outage event and the number of supported MTC devices....

  19. Efficient medium access control protocol for geostationary satellite systems

    Institute of Scientific and Technical Information of China (English)

    王丽娜; 顾学迈

    2004-01-01

    This paper proposes an efficient medium access control (MAC) protocol based on multifrequency-time division multiple access (MF-TDMA) for geostationary satellite systems deploying multiple spot-beams and onboard processing,which uses a method of random reservation access with movable boundaries to dynamically request the transmission slots and can transmit different types of traffic. The simulation results have shown that our designed MAC protocol can achieve a high bandwidth utilization, while providing the required quality of service (QoS) for each class of service.

  20. A RAMP CODE FOR FINE-GRAINED ACCESS CONTROL

    Directory of Open Access Journals (Sweden)

    Kannan Karthik

    2013-02-01

    Full Text Available Threshold ramp secret sharing schemes are designed so that (i certain subsets of shares have no information about the secret, (ii some subsets have partial information about the secret and (iii some subsets have complete information to recover the secret. However most of the ramp schemes in present literature do not control the leakage of information in partial access sets, due to which the information acquired by these sets is devoid of structure and not useful for fine-grained access control. Through a non-perfect secret sharing scheme called MIX-SPLIT, an encoding methodology for controlling the leakage in partial access sets is proposed and this is used for fine-grained access to binary strings. The ramp code generated using MIX-SPLIT requires a much smaller share size of O(n, as compared to Shamir's ramp adaptation which incurs a share size of atleast O(n2 for the same multi-access structure. The proposed ramp code is finally applied towards the protection and fine-grained access of industrial design drawings.

  1. Communication Dependent Control of Multi-Vehicle Formations

    Science.gov (United States)

    2016-05-11

    A TRIDENT SCHOLAR PROJECT REPORT NO. 450 Communication Dependent Control of Multi-Vehicle Formations by Midshipman 1/C Aaron M... COMMUNICATION DEPENDENT CONTROL OF MULTI-VEHICLE FORMATIONS by Midshipman 1/C Aaron M. Sims United States Naval Academy Annapolis, Maryland...REPORT DATE (DD-MM-YYYY) 05-11-2016 2. REPORT TYPE 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Communication Dependent Control of

  2. Communications and control for electric power systems

    Science.gov (United States)

    Kirkham, H.

    1992-01-01

    A long-term strategy for the integration of new control technologies for power generation and delivery is proposed: the industry would benefit from an evolutionary approach that would adapt to its needs future technologies as well as those that it has so far not heeded. The integrated operation of the entire system, including the distribution system, was proposed as a future goal. The AbNET communication protocols are reviewed, and additions that were made in 1991 are described. In the original network, traffic was controlled by polling at the master station, located at the substation, and routed by a flooding algorithm. In a revised version, the polling and flooding are modified. The question of interfacing low-energy measurement transducers or instrument transformers is considered. There is presently little or no agreement on what the output of optical current transducers (CT's) should be. Appendices deal with the calibration of current transducers; with Delta modulation, a simple means of serially encoding the output of an OCT; and with noise shaping, a method of digital signal processing that trades off the number of bits in a digital sample for a higher number of samples.

  3. Implicit and explicit communication in decentralized control

    CERN Document Server

    Grover, Pulkit

    2010-01-01

    There has been substantial progress recently in understanding toy problems of purely implicit signaling. These are problems where the source and the channel are implicit -- the message is generated endogenously by the system, and the plant itself is used as a channel. In this paper, we explore how implicit and explicit communication can be used synergistically to reduce control costs. The setting is an extension of Witsenhausen's counterexample where a rate-limited external channel connects the two controllers. Using a semi-deterministic version of the problem, we arrive at a binning-based strategy that can outperform the best known strategies by an arbitrarily large factor. We also show that our binning-based strategy attains within a constant factor of the optimal cost for an asymptotically infinite-length version of the problem uniformly over all problem parameters and all rates on the external channel. For the scalar case, although our results yield approximate optimality for each fixed rate, we are unabl...

  4. Enhancing Data Security and Access Control in Cloud Environment using Modified Attribute Based Encryption Mechanism

    Directory of Open Access Journals (Sweden)

    Apurva R. Naik

    2016-10-01

    Full Text Available Social networking and growing popularity of cloud services have made everyone to communicate each other in an easiest way. File sharing and distribution are the frequently used services provided by cloud service providers, although these facilities reduce cost of data sharing but at the same time data security and access control is the major problem. Many renowned service providers have faced the challenges to secure data and provide better access control, and we know once the data is leaked we cannot recover the data loss. Thus in order to ensure better security we need for focus on the two major problems, and those are access control and encryption policy. Cipher text policy attribute based encryption is the most effective solution for access control in real time scenarios where owner can actually decide the access rights for the end-user, but it comes with key escrow problem. We are proposing our modified escrow-free key issuing protocol to solve the problem of key escrow and our Modified Attribute Based Encryption scheme to achieve all security requirements to get a robust and secure system. Further we evaluate our model on the basis of results and lastly we conclude the paper.

  5. Researchers' perspectives on open access scholarly communication in Tanzanian public universities

    Directory of Open Access Journals (Sweden)

    F.W. Dulle

    2009-04-01

    Full Text Available This research explored the awareness, usage and perspectives of Tanzanian researchers on open access as a mode of scholarly communication. A survey questionnaire targeted 544 respondents selected through stratified random sampling from a population of 1088 university researchers of the six public universities in Tanzania. With a response rate of 73%, the data were analysed using the Statistical Package for Social Sciences. The study reveals that the majority of the researchers were aware of and were positive towards open access. Findings further indicate that the majority of researchers in Tanzanian public universities used open access outlets more to access scholarly content than to disseminate their own research findings. It seems that most of these researchers would support open access publishing more if issues of recognition, quality and ownership were resolved. Thus many of them supported the idea of establishing institutional repositories at their respective universities as a way of improving the dissemination of local content. The study recommends that public universities and other research institutions in the country should consider establishing institutional repositories, with appropriate quality assurance measures, to improve the dissemination of research output emanating from these institutions.

  6. Analyzing Accuracy and Accessibility in Information and Communication Technology Ethical Scenario Context

    Directory of Open Access Journals (Sweden)

    M. Masrom

    2011-01-01

    Full Text Available Problem statement: Recently, the development of Information and Communication Technology (ICT is indispensable to life. The utilization of ICT has provided advantages for people, organizations and society as a whole. Nevertheless, the widespread and rapid use of ICT in society has exacerbated existing ethical issues or dilemmas and also led to the emergence of new ethical issues such as unauthorized access, software piracy, internet pornography, privacy protection, information gap and many others. Approach: Therefore, the aim of this study is to discuss several issues of the ICT ethics. It will focusing on two major issues, that is, data accuracy and accessibility. Results: The results indicated that more than half percentage of respondents tend to be ethical in data accuracy scenario and also in accessibility scenario. Several computer ethics scenarios that relate to the data accuracy and accessibility are presented and the results of analysis are then discussed. Conclusion: Based on the results in this study, computer ethics issues such as data accuracy and accessibility should receive more attention in the ICT field.

  7. Using a Checklist to Access Communication Skills in Last Year Medical Students

    Directory of Open Access Journals (Sweden)

    Amini M

    2008-10-01

    Full Text Available Background and purpose: Available data indicate the quality of doctor-patient communication has a significant impact on patient satisfaction, medical outcomes, medical costs, and the likelihood of a physician experiencing a malpractice claim. Assessment of communication skills is a very important issue. Since a good assessment can show strengths and weaknesses of this process and feedback can improve the behavior, this study was designed to measure communication skill of last year medical students (interns in Jahrom medical school by an observational checklist. Methods: This study is a cross sectional study to access communication skills of interns of Jahrom medical school in southeast Iran, a checklist was designed for this purpose. Checklist completed with direct observation by an educated general practitioner. The researcher observed the interns in Motahari and Peymanie,(2 teaching hospitals of Jahrom medical school.The interns ignored about checklist material to prevent observational bias. Findings were analyzed using SPSS software. Results: 32(55%of medical interns were female and 26(45% were male. under category of interview conduction the best results was due to acceptable appearance of interns that 48 interns(82.8%had acceptable appearance. nearly half of the interns didn’t say hello to patients and great them. none of the interns introduce themselves to patients. . Under category of interview conduction the best results was due to responding properly to patient questions. Under category of interview completion the results showed that the behavior of interns in this part was not acceptable and this part of communication was the worst part. Conclusion: The results of our study reflect that it is necessary to introduce a sustained, coherent and integrated communication skill training program into the medical curriculum. Key words: COMMUNICATION SKILLS, INTERNS, ASSESSMENT

  8. Session Types for Access and Information Flow Control

    OpenAIRE

    Capecchi, Sara; Castellani, Ilaria; Dezani-Ciancaglini, Mariangiola; Rezk, Tamara

    2010-01-01

    We consider a calculus for multiparty sessions with delegation, enriched with security levels for session participants and data. We propose a type system that guarantees both session safety and a form of access control. Moreover, this type system ensures secure information flow, including controlled forms of declassification. In particular, it prevents leaks due to the specific control constructs of the calculus, such as session opening, selection, branching and delegation. We illustrate the ...

  9. Controlling user access to electronic resources without password

    Science.gov (United States)

    Smith, Fred Hewitt

    2015-06-16

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes pre-determining an association of the restricted computer resource and computer-resource-proximal environmental information. Indicia of user-proximal environmental information are received from a user requesting access to the restricted computer resource. Received indicia of user-proximal environmental information are compared to associated computer-resource-proximal environmental information. User access to the restricted computer resource is selectively granted responsive to a favorable comparison in which the user-proximal environmental information is sufficiently similar to the computer-resource proximal environmental information. In at least some embodiments, the process further includes comparing user-supplied biometric measure and comparing it with a predetermined association of at least one biometric measure of an authorized user. Access to the restricted computer resource is granted in response to a favorable comparison.

  10. On the performance of shared access control strategy for femtocells

    KAUST Repository

    Magableh, Amer M.

    2013-02-18

    Femtocells can be employed in cellular systems to enhance the indoor coverage, especially in the areas with high capacity growing demands and high traffic rates. In this paper, we propose an efficient resource utilization protocol, named as shared access protocol (SAP), to enable the unauthorized macrocell user equipment to communicate with partially closed-access femtocell base station to improve and enhance the system performance. The system model considers a femtocell that is equipped with a total of N separated antennas or channels to multiplex independent traffic. Then, a set of N1 channels is used for closed access only by the authorized users, and the remaining set of channel resources can be used for open access by either authorized or unauthorized users upon their demands and spatial locations. For this system model, we obtain the signal-to-interference ratio characteristics, such as the distribution and the moment generating function, in closed forms for two fading models of indoor and outdoor environments. The signal-tointerference ratio statistics are then used to derive some important performance measures of the proposed SAP in closed form, such as the average bit error rate, outage probability, and average channel capacity for the two fading models under consideration. Numerical results for the obtained expressions are provided and supported by Monte Carlo simulations to validate the analytical development and study the effectiveness of the proposed SAP under different conditions. Copyright © 2012 John Wiley and Sons, Ltd.

  11. Access Control with RFID in the Internet of Things

    DEFF Research Database (Denmark)

    Jensen, Steffen Elstrøm Holst; Jacobsen, Rune Hylsberg

    2013-01-01

    , to the Internet is suggested. The solution uses virtual representations of objects by using low-cost, passive RFID tags to give objects identities on the Internet. A prototype that maps an RFID identity into an IPv6 address is constructed. It is illustrated how this approach can be used in access control systems...... based on open network protocols and packet filtering. The solution includes a novel RFID reader architecture that supports the internetworking of components of a future access control system based on network layer technology....

  12. Communication in command and control teams

    NARCIS (Netherlands)

    Schraagen, J.M.C.; Rasker, P.C.

    2001-01-01

    An important factor affecting team performance in Combat Information Centers is communication. Previous research has shown that high-performing teams use effective communication patterns, such as limiting idle chatter during high workload conditions, and sharing information before it is needed.

  13. Control-theoretic Approach to Communication with Feedback: Fundamental Limits and Code Design

    CERN Document Server

    Ardestanizadeh, Ehsan

    2010-01-01

    Feedback communication is studied from a control-theoretic perspective, mapping the communication problem to a control problem in which the control signal is received through the same noisy channel as in the communication problem, and the (nonlinear and time-varying) dynamics of the system determine a subclass of encoders available at the transmitter. The MMSE capacity is defined to be the supremum exponential decay rate of the mean square decoding error. This is upper bounded by the information-theoretic feedback capacity, which is the supremum of the achievable rates. A sufficient condition is provided under which the upper bound holds with equality. For the special class of stationary Gaussian channels, a simple application of Bode's integral formula shows that the feedback capacity, recently characterized by Kim, is equal to the maximum instability that can be tolerated by the controller under a given power constraint. Finally, the control mapping is generalized to the N-sender AWGN multiple access channe...

  14. Navy Commercial Access Control System Did Not Effectively Mitigate Access Control Risks

    Science.gov (United States)

    2013-09-16

    the capability to perform NCIC checks to vet contractor employees, and not all Navy installations nave the ability to access NCIC, NCACS is not...Management Corp 10,017 REA to contract N40085-06-D-1260 Goodwill Industries 199,148 Overhead charge to contract N00189-09- C-Z003 DynCorp international

  15. High security chaotic multiple access scheme for visible light communication systems with advanced encryption standard interleaving

    Science.gov (United States)

    Qiu, Junchao; Zhang, Lin; Li, Diyang; Liu, Xingcheng

    2016-06-01

    Chaotic sequences can be applied to realize multiple user access and improve the system security for a visible light communication (VLC) system. However, since the map patterns of chaotic sequences are usually well known, eavesdroppers can possibly derive the key parameters of chaotic sequences and subsequently retrieve the information. We design an advanced encryption standard (AES) interleaving aided multiple user access scheme to enhance the security of a chaotic code division multiple access-based visible light communication (C-CDMA-VLC) system. We propose to spread the information with chaotic sequences, and then the spread information is interleaved by an AES algorithm and transmitted over VLC channels. Since the computation complexity of performing inverse operations to deinterleave the information is high, the eavesdroppers in a high speed VLC system cannot retrieve the information in real time; thus, the system security will be enhanced. Moreover, we build a mathematical model for the AES-aided VLC system and derive the theoretical information leakage to analyze the system security. The simulations are performed over VLC channels, and the results demonstrate the effectiveness and high security of our presented AES interleaving aided chaotic CDMA-VLC system.

  16. Database design for Physical Access Control System for nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Sathishkumar, T., E-mail: satishkumart@igcar.gov.in; Rao, G. Prabhakara, E-mail: prg@igcar.gov.in; Arumugam, P., E-mail: aarmu@igcar.gov.in

    2016-08-15

    Highlights: • Database design needs to be optimized and highly efficient for real time operation. • It requires a many-to-many mapping between Employee table and Doors table. • This mapping typically contain thousands of records and redundant data. • Proposed novel database design reduces the redundancy and provides abstraction. • This design is incorporated with the access control system developed in-house. - Abstract: A (Radio Frequency IDentification) RFID cum Biometric based two level Access Control System (ACS) was designed and developed for providing access to vital areas of nuclear facilities. The system has got both hardware [Access controller] and software components [server application, the database and the web client software]. The database design proposed, enables grouping of the employees based on the hierarchy of the organization and the grouping of the doors based on Access Zones (AZ). This design also illustrates the mapping between the Employee Groups (EG) and AZ. By following this approach in database design, a higher level view can be presented to the system administrator abstracting the inner details of the individual entities and doors. This paper describes the novel approach carried out in designing the database of the ACS.

  17. [Style of communication between mission control centers and space crews].

    Science.gov (United States)

    Iusupova, A K; Gushchin, V I; Shved, D M; Cheveleva, L M

    2011-01-01

    The article deals with a pilot investigation into the audio communication of cosmonauts with ground controllers. The purpose was to verify in space flight the patterns and trends revealed in model tests of intergroup communication, and to pinpoint the signature of multinational crew communication with 2 national mission control centers (MCCs). The investigation employed authors' content-analysis adapted to the scenario of long-duration mission. The investigation resulted in a phenomenon of double-loop ground-orbit communication, divergence, difference in opinion predictable from the concept formulated by G.T.Beregovoi. Also, there was a notable difference of expressions used by controllers of 2 MCCs.

  18. An Efficient Radio Access Control Mechanism for Wireless Network-On-Chip Architectures

    Directory of Open Access Journals (Sweden)

    Maurizio Palesi

    2015-03-01

    Full Text Available Modern systems-on-chip (SoCs today contain hundreds of cores, and this number is predicted to reach the thousands by the year 2020. As the number of communicating elements increases, there is a need for an efficient, scalable and reliable communication infrastructure. As technology geometries shrink to the deep submicron regime, however, the communication delay and power consumption of global interconnections become the major bottleneck. The network-on-chip (NoC design paradigm, based on a modular packet-switched mechanism, can address many of the on-chip communication issues, such as the performance limitations of long interconnects and integration of large number of cores on a chip. Recently, new communication technologies based on the NoC concept have emerged with the aim of improving the scalability limitations of conventional NoC-based architectures. Among them, wireless NoCs (WiNoCs use the radio medium for reducing the performance and energy penalties of long-range and multi-hop communications. As the radio medium can be accessed by a single transmitter at a time, a radio access control mechanism (RACM is needed. In this paper, we present a novel RACM, which allows one to improve both the performance and energy figures of the WiNoC. Experiments, carried out on both synthetic and real traffic scenarios, have shown the effectiveness of the proposed RACM. On average, a 30% reduction in communication delay and a 25% energy savings have been observed when the proposed RACM is applied to a known WiNoC architecture.

  19. Review of Access Control Models for Cloud Computing

    Directory of Open Access Journals (Sweden)

    Natarajan Meghanathan

    2013-05-01

    Full Text Available The relationship between users and resources is dyn amic in the cloud, and service providers and users are typically not in the same security do main. Identity-based security (e.g., discretionary or mandatory access control models c annot be used in an open cloud computing environment, where each resource node may not be fa miliar, or even do not know each other. Users are normally identified by their attributes o r characteristics and not by predefined identities. There is often a need for a dynamic acc ess control mechanism to achieve cross- domain authentication. In this paper, we will focus on the following three broad categories of access control models for cloud computing: (1 Role -based models; (2 Attribute-based encryption models and (3 Multi-tenancy models. We will review the existing literature on each of the above access control models and their varian ts (technical approaches, characteristics, applicability, pros and cons, and identify future research directions for developing access control models for cloud computing environments .

  20. Regulatory Accessibility and Social Influences on State Self-Control

    OpenAIRE

    vanDellen, Michelle R.; Hoyle, Rick H.

    2009-01-01

    The current work examined how social factors influence self-control. Current conceptions of state self-control treat it largely as a function of regulatory capacity. The authors propose that state self-control might also be influenced by social factors because of regulatory accessibility. Studies 1 through 4 provide evidence that individuals’ state self-control is influenced by the trait and state self-control of salient others such that thinking of others with good trait or state self-contro...

  1. Access Control of Web and Java Based Applications

    Science.gov (United States)

    Tso, Kam S.; Pajevski, Michael J.; Johnson, Bryan

    2011-01-01

    Cyber security has gained national and international attention as a result of near continuous headlines from financial institutions, retail stores, government offices and universities reporting compromised systems and stolen data. Concerns continue to rise as threats of service interruption, and spreading of viruses become ever more prevalent and serious. Controlling access to application layer resources is a critical component in a layered security solution that includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. In this paper we discuss the development of an application-level access control solution, based on an open-source access manager augmented with custom software components, to provide protection to both Web-based and Java-based client and server applications.

  2. An analysis of constraints on access to augmentative communication in cerebral palsy.

    Science.gov (United States)

    Costigan, F Aileen; Newell, Karl M

    2009-06-01

    Effective use of augmentative communication requires an individual to manage its technical aspects. Motor-skill limitations in cerebral palsy (i.e., individual constraints) can influence this ability as can demands imposed by communication devices (i.e., task constraints). This paper emphasizes the importance of analyzing the confluence of task and individual constraints in promoting a functional fit between the individual with cerebral palsy and the communication device. We demonstrate the utility of current principles of motor control in analyzing this confluence. Task constraints imposed by target selection and individual constraints imposed by cerebral palsy are introduced prior to an analysis of their confluence using the degrees of freedom of the potential planes of limb motion. Occupational therapists should look beyond motor-skill assessment to the confluence of task and individual constraints when customizing target selection in augmentative communication.

  3. Communication and control tools, systems, and new dimensions

    CERN Document Server

    MacDougall, Robert; Cummings, Kevin

    2015-01-01

    Communication and Control: Tools, Systems, and New Dimensions advocates a systems view of human communication in a time of intelligent, learning machines. This edited collection sheds new light on things as mundane yet still profoundly consequential (and seemingly "low-tech") today as push buttons, pagers and telemarketing systems. Contributors also investigate aspects of "remote control" related to education, organizational design, artificial intelligence, cyberwarfa

  4. Communicative social capital and collective efficacy as determinants of access to health-enhancing resources in residential communities.

    Science.gov (United States)

    Matsaganis, Matthew D; Wilkin, Holley A

    2015-04-01

    This article contributes to the burgeoning literature on the social determinants of health disparities. The authors investigate how communication resources and collective efficacy, independently and in combination, shape residents' access to health enhancing resources (including healthcare services, sources of healthier food options, and public recreation spaces) in their communities. Using random digit dial telephone survey data from 833 residents of South Los Angeles communities the authors show that communicative social capital-that is, an information and problem-solving resource that accrues to residents as they become more integrated into their local communication network of neighbors, community organizations, and local media-plays a significant role in access to health resources. This relationship is complicated by individuals' health insurance and health status, as communicative social capital magnifies the sense of absence of resources for those who are in worse health and lack insurance. Communicative social capital builds collective efficacy, which is positively related to access to health-enhancing resources, but it also mediates the negative relationship between communicative social capital and access to health resources. Residents with richer stores of communicative social capital and collective efficacy report better access to health resources. The authors conclude with a discussion of implications of these findings and suggestions for future research.

  5. Future Communication, Computing, Control and Management Volume 1

    CERN Document Server

    2012-01-01

    This volume contains revised and extended research articles written by prominent researchers participating in the ICF4C 2011 conference. 2011 International Conference on Future Communication, Computing, Control and Management (ICF4C 2011) has been held on December 16-17, 2011, Phuket, Thailand. Topics covered include intelligent computing, network management, wireless networks, telecommunication, power engineering, control engineering, Signal and Image Processing, Machine Learning, Control Systems and Applications, The book will offer the states of arts of tremendous advances in Computing, Communication, Control, and Management and also serve as an excellent reference work for researchers and graduate students working on Computing, Communication, Control, and Management Research.

  6. Future Communication, Computing, Control and Management Volume 2

    CERN Document Server

    2012-01-01

    This volume contains revised and extended research articles written by prominent researchers participating in the ICF4C 2011 conference. 2011 International Conference on Future Communication, Computing, Control and Management (ICF4C 2011) has been held on December 16-17, 2011, Phuket, Thailand. Topics covered include intelligent computing, network management, wireless networks, telecommunication, power engineering, control engineering, Signal and Image Processing, Machine Learning, Control Systems and Applications, The book will offer the states of arts of tremendous advances in Computing, Communication, Control, and Management and also serve as an excellent reference work for researchers and graduate students working on Computing, Communication, Control, and Management Research.

  7. Future Computing, Communication, Control and Management Volume 2

    CERN Document Server

    2012-01-01

    This volume contains revised and extended research articles written by prominent researchers participating in the ICF4C 2011 conference. 2011 International Conference on Future Communication, Computing, Control and Management (ICF4C 2011) has been held on December 16-17, 2011, Phuket, Thailand. Topics covered include intelligent computing, network management, wireless networks, telecommunication, power engineering, control engineering, Signal and Image Processing, Machine Learning, Control Systems and Applications, The book will offer the states of arts of tremendous advances in Computing, Communication, Control, and Management and also serve as an excellent reference work for researchers and graduate students working on Computing, Communication, Control, and Management Research.

  8. Global system data bus using the Digital Autonomous Terminal Access Communication protocol

    Science.gov (United States)

    Holmes, David C. E.

    1986-01-01

    Modern digital avionic systems with distributed processing require networking to connect the many elements. Digital Autonomous Terminal Access Communication (DATAC) is one of many such networks. DATAC has been implemented on the Transport Systems Research Vehicle (TSRV), a Boeing 737 aircraft operated by the National Aeronautics and Space Administration's Advanced Transport Operating Systems Program Office (ATOPS). This paper presents the TSRV implementation of the DATAC bus, a description of the DATAC system, a synchronization mechanism, details of data flow throughout the system, and a discussion of the modes available with DATAC. Numerous flight tests have been conducted using DATAC as the only means of communication between systems with outstanding results. DATAC is now an integral part of the TSRV and is expected to satisfy near term as well as future requirements for growth and flexibility.

  9. Outline of a multiple-access communication network based on adaptive arrays

    Science.gov (United States)

    Zohar, S.

    1982-01-01

    Attention is given to a narrow-band communication system consisting of a central station trying to receive signals simultaneously from K spatially distinct mobile users sharing the same frequencies. One example of such a system is a group of aircraft and ships transmitting messages to a communication satellite. A reasonable approach to such a multiple access system may be based on equipping the central station with an n-element antenna array where n is equal to or greater than K. The array employs K sets of n weights to segregate the signals received from the K users. The weights are determined by direct computation based on position information transmitted by the users. A description is presented of an improved technique which makes it possible to reduce significantly the number of required computer operations in comparison to currently known techniques.

  10. Nanorack Compatible Standardized Data Processing, Communication, and Control Module Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I study will design and develop a NanoRacks Control Module (NCM) that provides communications, control functions and data processing in a NanoRacks...

  11. Ubiquitous access control and policy management in personal networks

    DEFF Research Database (Denmark)

    Kyriazanos, Dimitris M.; Stassinopoulos, George I.; Prasad, Neeli R.

    2006-01-01

    In this paper the authors present the challenges for enabling Security Policies Management and subsequent Ubiquitous Access Control on the Personal Network (PN) environment. A solution based on Security Profiles is proposed, supporting both partially distributed architectures-having in this case...

  12. Fine-Grained Access Control for Electronic Health Record Systems

    Science.gov (United States)

    Hue, Pham Thi Bach; Wohlgemuth, Sven; Echizen, Isao; Thuy, Dong Thi Bich; Thuc, Nguyen Dinh

    There needs to be a strategy for securing the privacy of patients when exchanging health records between various entities over the Internet. Despite the fact that health care providers such as Google Health and Microsoft Corp.'s Health Vault comply with the U.S Health Insurance Portability and Accountability Act (HIPAA), the privacy of patients is still at risk. Several encryption schemes and access control mechanisms have been suggested to protect the disclosure of a patient's health record especially from unauthorized entities. However, by implementing these approaches, data owners are not capable of controlling and protecting the disclosure of the individual sensitive attributes of their health records. This raises the need to adopt a secure mechanism to protect personal information against unauthorized disclosure. Therefore, we propose a new Fine-grained Access Control (FGAC) mechanism that is based on subkeys, which would allow a data owner to further control the access to his data at the column-level. We also propose a new mechanism to efficiently reduce the number of keys maintained by a data owner in cases when the users have different access privileges to different columns of the data being shared.

  13. Audit-Based Access Control for Electronic Health Records

    NARCIS (Netherlands)

    Dekker, M.A.C.; Etalle, Sandro

    2006-01-01

    Traditional access control mechanisms aim to prevent illegal actions a-priori occurrence, i.e. before granting a request for a document. There are scenarios however where the security decision can not be made on the fly. For these settings we developed a language and a framework for a-posteriori

  14. Access Control for Agent-based Computing: A Distributed Approach.

    Science.gov (United States)

    Antonopoulos, Nick; Koukoumpetsos, Kyriakos; Shafarenko, Alex

    2001-01-01

    Discusses the mobile software agent paradigm that provides a foundation for the development of high performance distributed applications and presents a simple, distributed access control architecture based on the concept of distributed, active authorization entities (lock cells), any combination of which can be referenced by an agent to provide…

  15. Secure Dynamic access control scheme of PHR in cloud computing.

    Science.gov (United States)

    Chen, Tzer-Shyong; Liu, Chia-Hui; Chen, Tzer-Long; Chen, Chin-Sheng; Bau, Jian-Guo; Lin, Tzu-Ching

    2012-12-01

    With the development of information technology and medical technology, medical information has been developed from traditional paper records into electronic medical records, which have now been widely applied. The new-style medical information exchange system "personal health records (PHR)" is gradually developed. PHR is a kind of health records maintained and recorded by individuals. An ideal personal health record could integrate personal medical information from different sources and provide complete and correct personal health and medical summary through the Internet or portable media under the requirements of security and privacy. A lot of personal health records are being utilized. The patient-centered PHR information exchange system allows the public autonomously maintain and manage personal health records. Such management is convenient for storing, accessing, and sharing personal medical records. With the emergence of Cloud computing, PHR service has been transferred to storing data into Cloud servers that the resources could be flexibly utilized and the operation cost can be reduced. Nevertheless, patients would face privacy problem when storing PHR data into Cloud. Besides, it requires a secure protection scheme to encrypt the medical records of each patient for storing PHR into Cloud server. In the encryption process, it would be a challenge to achieve accurately accessing to medical records and corresponding to flexibility and efficiency. A new PHR access control scheme under Cloud computing environments is proposed in this study. With Lagrange interpolation polynomial to establish a secure and effective PHR information access scheme, it allows to accurately access to PHR with security and is suitable for enormous multi-users. Moreover, this scheme also dynamically supports multi-users in Cloud computing environments with personal privacy and offers legal authorities to access to PHR. From security and effectiveness analyses, the proposed PHR access

  16. High-Capacity Hybrid Optical Fiber-Wireless Communications Links in Access Networks

    DEFF Research Database (Denmark)

    Pang, Xiaodan

    techniques with both coherent and incoherent optical sources are studied and demonstrated. Employments of advanced modulation formats including phase-shift keying (PSK), M-quadrature amplitude modulation (QAM) and orthogonal frequency-division multiplexing (OFDM) for high speed photonic-wireless transmission......Integration between fiber-optic and wireless communications systems in the "last mile" access networks is currently considered as a promising solution for both service providers and users, in terms of minimizing deployment cost, shortening upgrading period and increasing mobility and flexibility...... techniques. In conclusion, the results presented in the thesis show the feasibility of employing mm-wave signals, advanced modulation formats and spatial multiplexing technologies in next generation high capacity hybrid optical fiber-wireless access systems....

  17. IEPLC Framework, Automated Communication in a Heterogeneous Control System Environment

    CERN Document Server

    Locci, F

    2014-01-01

    In CERN accelerators control system several components are essential such as: Programmable Logic Controller (PLC), PCI Extensions for Instrumentation (PXI), and other micro-controller families. Together with their weaknesses and their strength points they typically present custom communication protocols and it is therefore difficult to federate them into the control system using a single communication strategy. Furthermore this dependency to the physical device interfaces and protocols makes most of the code not reusable and the replacement of old technology a difficult problem. The purpose of IEPLC ([1]) is to mitigate the communication issues given by this heterogeneity; it proposes a framework to define communication interfaces in a hardware independent manner. In addition it automatically generates all the resources needed on master side (typically represented by a FEC: Front-End Computer) and slave side (typically represented by the controller) to implement a common and generic Ethernet communication. Th...

  18. Optical code division multiple access secure communications systems with rapid reconfigurable polarization shift key user code

    Science.gov (United States)

    Gao, Kaiqiang; Wu, Chongqing; Sheng, Xinzhi; Shang, Chao; Liu, Lanlan; Wang, Jian

    2015-09-01

    An optical code division multiple access (OCDMA) secure communications system scheme with rapid reconfigurable polarization shift key (Pol-SK) bipolar user code is proposed and demonstrated. Compared to fix code OCDMA, by constantly changing the user code, the performance of anti-eavesdropping is greatly improved. The Pol-SK OCDMA experiment with a 10 Gchip/s user code and a 1.25 Gb/s user data of payload has been realized, which means this scheme has better tolerance and could be easily realized.

  19. Broadband wireless communications for railway applications for onboard internet access and other applications

    CERN Document Server

    Masson, Émilie

    2017-01-01

    This book focuses on the needs of railway operators in terms of wireless communications, divided in two main categories: the commercial services and the operational needs. Then, all available technologies that can be used to provide Internet access on board trains and all the other operational applications requiring high capacity are detailed. Finally, challenges and trends in railway telecommunications are highlighted, through the presentation of the future and emerging technologies, the current discussions and works in the different authorities, and the key challenges and scientific barriers.

  20. Fuzzy logic controller to improve powerline communication

    Science.gov (United States)

    Tirrito, Salvatore

    2015-12-01

    The Power Line Communications (PLC) technology allows the use of the power grid in order to ensure the exchange of data information among devices. This work proposes an approach, based on Fuzzy Logic, that dynamically manages the amplitude of the signal, with which each node transmits, by processing the master-slave link quality measured and the master-slave distance. The main objective of this is to reduce both the impact of communication interferences induced and power consumption.

  1. Radio communication for Communications-Based Train Control (CBTC): A tutorial and survey

    DEFF Research Database (Denmark)

    Farooq, Jahanzeb; Soler, José

    2017-01-01

    industry. We believe that this paper fills the much-needed gap. It aims to present a comprehensive tutorial, as well as a survey of the stateof- the-art, of CBTC and the role of radio communication in it. The operation and fundamental components of a CBTC system are discussed. A summary of the evolution...... of the communication technologies used for modern railway signalling is presented. The benefits and drawbacks of using a radio communication technology, particularly Wi-Fi, and the challenges it introduces, are discussed. Best practices in the design of a CBTC radio network and the measures to optimize its......Over the last decade, railway industry has seen a huge transition from conventional railway signalling systems to modern, communication-based signalling systems. Communications-Based Train Control (CBTC) is a modern communication-based system that uses radio communication to transfer timely...

  2. Compulsory licensing, price controls, and access to patented foreign products

    OpenAIRE

    Eric Bond; Kamal Saggi

    2012-01-01

    Motivated by existing multilateral rules regarding intellectual property, we develop a North-South model to highlight the dual roles price controls and compulsory licensing play in determining Southern access to a patented Northern product. The Northern patent-holder chooses whether and how to work its patent in the South (either via entry or voluntarily licensing) while the South determines the price control and whether to issue a compulsory license. The threat of compulsory licensing benefi...

  3. Predicting Social Networking Site Use and Online Communication Practices among Adolescents: The Role of Access and Device Ownership

    OpenAIRE

    Drew P. Cingel; Alexis R. Lauricella; Ellen Wartella; Annie Conway

    2014-01-01

    Given adolescents' heavy social media use, this study examined a number of predictors of adolescent social media use, as well as predictors of online communication practices. Using data collected from a national sample of 467 adolescents between the ages of 13 and 17, results indicate that demographics, technology access, and technology ownership are related to social media use and communication practices. Specifically, females log onto and use more constructive com-munication practices on Fa...

  4. Medium Access Control in Energy Harvesting - Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon

    Control (MAC) protocols that are following the receiver-initiated paradigm of asynchronous communication. According to the receiver-initiated paradigm the communication is initiated by the receiver that states its availability to receive data through beacons. The sender is passively listening...... to the channel until it receives the beacon of interest. In this context, the dissertation begins with an in-depth survey of all the receiverinitiated MAC protocols and presents their unique optimization features, which deal with several challenges of the link layer such as mitigation of the energy consumption......-efficient features that aim to adapt the consumed energy to match the harvested energy, distribute the load with respect to the harvested energy, decrease the overhead of the communication, address the requirements for collision avoidance, prioritize urgent traffic and secure the system against beacon replay attacks...

  5. Integrity Based Access Control Model for Multilevel XML Document

    Institute of Scientific and Technical Information of China (English)

    HONG Fan; FENG Xue-bin; HUANO Zhi; ZHENG Ming-hui

    2008-01-01

    XML's increasing popularity highlights the security demand for XML documents. A mandatory access control model for XML document is presented on the basis of investigation of the function dependency of XML documents and discussion of the integrity properties of multilevel XML document. Then, the algorithms for decomposition/recovery multilevel XML document into/from single level document are given, and the manipulation rules for typical operations of XQuery and XUpdate: QUERY, INSERT,UPDATE, and REMOVE, are elaborated. The multilevel XML document access model can meet the requirement of sensitive information processing application.

  6. Analysis of routine communication in the air traffic control system

    Science.gov (United States)

    Clark, Herbert H.; Morrow, Daniel; Rodvoid, Michelle

    1990-01-01

    The present project has three related goals. The first is to describe the organization of routine controller-pilot communication. This includes identifying the basic units of communication and how they are organized into discourse, how controllers and pilots use language to achieve their goals, and what topics they discuss. The second goal is to identify the type and frequency of problems that interrupt routine information transfer and prompt pilots and controllers to focus on the communication itself. The authors analyze the costs of these problems in terms of communication efficiency, and the techniques used to resolve these problems. Third, the authors hope to identify factors associated with communication problems, such as deviations from conventional air traffic control procedures.

  7. Quantum control without access to the controlling interaction

    CERN Document Server

    Janzing, D; Zeier, R; Beth, T; Janzing, Dominik; Armknecht, Frederik; Zeier, Robert; Beth, Thomas

    2001-01-01

    In our model a fixed Hamiltonian acts on the joint Hilbert space of a quantum system and its controller. We show under which conditions measurements, state preparations, and unitary implementations on the system can be performed by quantum operations on the controller only. It turns out that a measurement of the observable A and an implementation of the one-parameter group exp(iAr) can be performed by almost the same sequence of control operations. Furthermore measurement procedures for A+B, for (AB+BA), and for i[A,B] can be constructed from measurements of A and B. This shows that the algebraic structure of the set of observables can be explained by the Lie group structure of the unitary evolutions on the joint Hilbert space of the measuring device and the measured system. A spin chain model with nearest neighborhood coupling shows that the border line between controller and system can be shifted consistently.

  8. Identity Authentication and Capability Based Access Control (IACAC) for the Internet of Things

    DEFF Research Database (Denmark)

    Mahalle, Parikshit N.; Anggorojati, Bayu; Prasad, Neeli R.

    2013-01-01

    and weak physical security of low power devices in IoT networks are possible sources for security vulnerabilities. It is promising to make an authentication and access control attack resistant and lightweight in a resource constrained and distributed IoT environment. This paper presents the Identity...... is secure against aforementioned attacks. This paper also discusses performance analysis of the protocol in terms of computational time compared to other existing solutions. Furthermore, this paper addresses challenges in IoT and security attacks are modelled with the use cases to give an actual view of IoT......In the last few years the Internet of Things (IoT) has seen widespread application and can be found in each field. Authentication and access control are important and critical functionalities in the context of IoT to enable secure communication between devices. Mobility, dynamic network topology...

  9. Application of Attribute Based Access Control Model for Industrial Control Systems

    Directory of Open Access Journals (Sweden)

    Erkan Yalcinkaya

    2017-02-01

    Full Text Available The number of reported security vulnerabilities and incidents related to the industrial control systems (ICS has increased recent years. As argued by several researchers, authorization issues and poor access control are key incident vectors. The majority of ICS are not designed security in mind and they usually lack strong and granular access control mechanisms. The attribute based access control (ABAC model offers high authorization granularity, central administration of access policies with centrally consolidated and monitored logging properties. This research proposes to harness the ABAC model to address the present and future ICS access control challenges. The proposed solution is also implemented and rigorously tested to demonstrate the feasibility and viability of ABAC model for ICS.

  10. Design of a Distributed Personal Information Access Control Scheme for Secure Integrated Payment in NFC

    Directory of Open Access Journals (Sweden)

    Jungho Kang

    2015-06-01

    Full Text Available At the center of core technologies for a future cyber world, such as Internet of Things (IoT or big data, is a context-rich system that offers services by using situational information. The field where context-rich systems were first introduced is near-field communication (NFC-based electronic payments. Near-field Communication (NFC integrated payment services collect the payment information of the credit card and the location information to generate patterns in the user’s consumption or movement through big data technology. Based on such pattern information, tailored services, such as advertisement, are offered to users. However, there is difficulty in controlling access to personal information, as there is a collaborative relationship focused on the trusted service manager (TSM that is close knit to shared personal information. Moreover, in the case of Hadoop, among the many big data analytical technologies, it offers access control functions, but not a way to authorize the processing of personal information, making it impossible to grant authority between service providers to process information. As such, this paper proposes a key generation and distribution method, as well as a secure communication protocol. The analysis has shown that the efficiency was greater for security and performance compared to relation works.

  11. A formal model for access control with supporting spatial context

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong; HE YePing; SHI ZhiGuo

    2007-01-01

    There is an emerging recognition of the importance of utilizing contextual information in authorization decisions. Controlling access to resources in the field of wireless and mobile networking require the definition of a formal model for access control with supporting spatial context. However, traditional RBAC model does not specify these spatial requirements. In this paper, we extend the existing RBAC model and propose the SC-RBAC model that utilizes spatial and location-based information in security policy definitions. The concept of spatial role is presented,and the role is assigned a logical location domain to specify the spatial boundary.Roles are activated based on the current physical position of the user which obtained from a specific mobile terminal. We then extend SC-RBAC to deal with hierarchies, modeling permission, user and activation inheritance, and prove that the hierarchical spatial roles are capable of constructing a lattice which is a means for articulate multi-level security policy and more suitable to control the information flow security for safety-critical location-aware information systems. Next, constrained SC-RBAC allows express various spatial separations of duty constraints,location-based cardinality and temporal constraints for specify fine-grained spatial semantics that are typical in location-aware systems. Finally, we introduce 9 invariants for the constrained SC-RBAC and its basic security theorem is proven. The constrained SC-RBAC provides the foundation for applications in need of the constrained spatial context aware access control.

  12. Predicting Social Networking Site Use and Online Communication Practices among Adolescents: The Role of Access and Device Ownership

    Directory of Open Access Journals (Sweden)

    Drew P. Cingel

    2014-06-01

    Full Text Available Given adolescents' heavy social media use, this study examined a number of predictors of adolescent social media use, as well as predictors of online communication practices. Using data collected from a national sample of 467 adolescents between the ages of 13 and 17, results indicate that demographics, technology access, and technology ownership are related to social media use and communication practices. Specifically, females log onto and use more constructive com-munication practices on Facebook compared to males. Additionally, adolescents who own smartphones engage in more constructive online communication practices than those who share regular cell phones or those who do not have access to a cell phone. Overall, results imply that ownership of mobile technologies, such as smartphones and iPads, may be more predictive of social networking site use and online communication practices than general ownership of technology.

  13. Predicting Social Networking Site Use and Online Communication Practices among Adolescents: The Role of Access and Device Ownership

    Directory of Open Access Journals (Sweden)

    Drew P. Cingel

    2014-01-01

    Full Text Available Given adolescents' heavy social media use, this study examined a number of predictors of adolescent social media use, as well as predictors of online communication practices. Using data collected from a national sample of 467 adolescents between the ages of 13 and 17, results indicate that demographics, technology access, and technology ownership are related to social media use and communication practices. Specifically, females log onto and use more constructive communication practices on Facebook compared to males. Additionally, adolescents who own smartphones engage in more constructive online communication practices than those who share regular cell phones or those who do not have access to a cell phone. Overall, results imply that ownership of mobile technologies, such as smartphones and iPads, may be more predictive of social networking site use and online communication practices than general ownership of technology.

  14. Access Control Design and Implementations in the ATLAS Experiment

    CERN Document Server

    Leahu, M C; Avolio, G

    2008-01-01

    The ATLAS experiment operates with a significant number of hardware and software resources. Their protection against misuse is an essential task to ensure a safe and optimal operation. To achieve this goal, the Role Based Access Control (RBAC) model has been chosen for its scalability, flexibility, ease of administration and usability from the lowest operating system level to the highest software application level. This paper presents the overall design of RBAC implementation in the ATLAS experiment and the enforcement solutions in different areas such as the system administration, control room desktops and the data acquisition software. The users and the roles are centrally managed using a directory service based on Lightweight Directory Access Protocol which is kept in synchronization with the human resources and IT datab

  15. An approach to access control in electronic health record.

    Science.gov (United States)

    Sucurovic, Snezana

    2010-08-01

    OASIS is a non-for-profit consortium that drives the development convergence and adoption of open standards for the global information society. It involves more than 600 organizations and individuals as well as IT leaders Sun, Microsoft, IBM and Oracle. One of its standards is XACML which appeared a few years ago and now there are about 150,000 hits on Google. XACML (eXtensible Access Control Markup Language) is not technology related. Sun published in 2004 open source Sun XACML which is in compliance with XACML 1.0. specification and now works to make it comply with XACML 2.0. The heart of XACML are attributes values of defined type and name that is to be attached to a subject, a resource, an action and an environment in which a subject request action on resource. In that way XACML is to replace Role Based Access Control which dominated for years. The paper examines performances in CEN 13 606 and ISO 22 600 based healthcare system which uses XACML for access control.

  16. A fast microprocessor communication network design for interprocessor communications for an integrated flight control system

    Science.gov (United States)

    Kelly, G. L.; Jiang, P.-W.

    1982-01-01

    A node design with connectivity four is presented whose communication processor handles data at four million bits/sec on each of the four channels into the node, and on each of the four channels out of the node, for a total node capacity of 32 million bits/sec. An integrated flight control system real-time application of this communication network design is discussed. It is shown that such high speed node communication hardware, arranged in the topological configuration of a minimum diameter graph with connectivity four and all links active, has good potential for real time control applications requiring reliability, availability, and survivability characteristics.

  17. Results of an Iridium-Based Data Communication System Providing Internet Access to Polar Expeditions

    Science.gov (United States)

    Mohammad, A.; Frost, V.; Braaten, D.

    2003-12-01

    The Polar Radar for Ice Sheet Measurements (PRISM) Project at the University of Kansas has developed and field-tested a versatile communications system for use by researchers in high-latitude Polar Regions. The PRISM project is developing advanced intelligent remote sensing technology that involves radar systems, an autonomous rover, and communications systems to measure detailed ice sheet characteristics, and to determine bed conditions (frozen or wet) below active ice sheets in both Greenland and Antarctica. We also have a very strong public outreach and educational program aimed at K-12 educators and students that requires data, voice and video feeds from Polar field locations in near real time. Hence, PRISM requires a robust communications system for use in the field between a base camp and the mobile remote sensing system, and from the field back to the University of Kansas and onto the Internet. The communication system that has been developed is truly mobile and is relatively inexpensive. We initially considered various satellite services during the design phase of this project. The two feasible options for high-latitude locations were Iridium, with its low-bit-rate service (2.4 Kb/s), and Inmarsat/Intelsat with broadband service. We selected the Iridium option for testing and development because it provided coverage in both Antarctica and Greenland. To achieve higher capacity communications, the multilink point-to-point protocol (MLPPP) implemented in Linux was tuned to operate efficiently over the Iridium satellite system. This mechanism combines multiple channels to obtain a seamless data connection with a capacity equal to the sum of the individual link rates. We used four Iridium modems to obtain an aggregate capacity of about 9.6 Kb/s. Standard Internet protocols (TCP/IP) were then used to provide end-to-end connectivity. The communications system field experiments were conducted at the NorthGRIP ice core drilling camp in Greenland (75° 06' N, 42° 20

  18. Ressox Control of QZSS During Communication Interruption

    Science.gov (United States)

    2009-11-01

    model, Cr=1.2, 30 m2Solar radiation pressure model Moon , Sun, Mercury, Venus, Mars, Jupiter , Saturn, Uranus, Neptune, Pluto Other bodies x...QZSS During Communication Interruption 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK...NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) National Institute of Advanced Industrial Science and Technology

  19. Analysis of communication based distributed control of MMC for HVDC

    DEFF Research Database (Denmark)

    Huang, Shaojun; Teodorescu, Remus; Mathe, Laszlo

    2013-01-01

    methods and Matlab tools. Finally, sensitiveness of the distributed control system to modulation effect (phase-shifted PWM), communication delay, individual carrier frequency and sampling frequency is studied through simulations that are made in Matlab Simulink and PLECS....

  20. BARTER: Behavior Profile Exchange for Behavior-Based Admission and Access Control in MANETs

    Science.gov (United States)

    Frias-Martinez, Vanessa; Stolfo, Salvatore J.; Keromytis, Angelos D.

    Mobile Ad-hoc Networks (MANETs) are very dynamic networks with devices continuously entering and leaving the group. The highly dynamic nature of MANETs renders the manual creation and update of policies associated with the initial incorporation of devices to the MANET (admission control) as well as with anomaly detection during communications among members (access control) a very difficult task. In this paper, we present BARTER, a mechanism that automatically creates and updates admission and access control policies for MANETs based on behavior profiles. BARTER is an adaptation for fully distributed environments of our previously introduced BB-NAC mechanism for NAC technologies. Rather than relying on a centralized NAC enforcer, MANET members initially exchange their behavior profiles and compute individual local definitions of normal network behavior. During admission or access control, each member issues an individual decision based on its definition of normalcy. Individual decisions are then aggregated via a threshold cryptographic infrastructure that requires an agreement among a fixed amount of MANET members to change the status of the network. We present experimental results using content and volumetric behavior profiles computed from the ENRON dataset. In particular, we show that the mechanism achieves true rejection rates of 95% with false rejection rates of 9%.

  1. Directional Medium Access Control (MAC Protocols in Wireless Ad Hoc and Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    David Tung Chong Wong

    2015-06-01

    Full Text Available This survey paper presents the state-of-the-art directional medium access control (MAC protocols in wireless ad hoc and sensor networks (WAHSNs. The key benefits of directional antennas over omni-directional antennas are longer communication range, less multipath interference, more spatial reuse, more secure communications, higher throughput and reduced latency. However, directional antennas lead to single-/multi-channel directional hidden/exposed terminals, deafness and neighborhood, head-of-line blocking, and MAC-layer capture which need to be overcome. Addressing these problems and benefits for directional antennas to MAC protocols leads to many classes of directional MAC protocols in WAHSNs. These classes of directional MAC protocols presented in this survey paper include single-channel, multi-channel, cooperative and cognitive directional MACs. Single-channel directional MAC protocols can be classified as contention-based or non-contention-based or hybrid-based, while multi-channel directional MAC protocols commonly use a common control channel for control packets/tones and one or more data channels for directional data transmissions. Cooperative directional MAC protocols improve throughput in WAHSNs via directional multi-rate/single-relay/multiple-relay/two frequency channels/polarization, while cognitive directional MAC protocols leverage on conventional directional MAC protocols with new twists to address dynamic spectrum access. All of these directional MAC protocols are the pillars for the design of future directional MAC protocols in WAHSNs.

  2. Controlled English for Effective Communication during Coalition Operations

    Science.gov (United States)

    2013-06-01

    simplified and common form of expression in English , which is not only user- friendly in nature but is also restricted in vocabulary and grammar for clear...18th ICCRTS C2 in Underdeveloped, Degraded and Denied Operational Environments Title of Paper: Controlled English for Effective Communication...4. TITLE AND SUBTITLE Controlled English for Effective Communication during Coalition Operations 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  3. OJADEAC: An Ontology Based Access Control Model for JADE Platform

    Directory of Open Access Journals (Sweden)

    Ban Sharief Mustafa

    2014-06-01

    Full Text Available Java Agent Development Framework (JADE is a software framework to make easy the development of Multi-Agent applications in compliance with the Foundation for Intelligent Physical Agents (FIPA specifications. JADE propose new infrastructure solutions to support the development of useful and convenient distributed applications. Security is one of the most important issues in implementing and deploying such applications. JADE-S security add-ons are one of the most popular security solutions in JADE platform. It provides several security services including authentication, authorization, signature and encryption services. Authorization service will give authorities to perform an action based on a set of permission objects attached to every authenticated user. This service has several drawbacks when implemented in a scalable distributed context aware applications. In this paper, an ontology-based access control model called (OJADEAC is proposed to be applied in JADE platform by combining Semantic Web technologies with context-aware policy mechanism to overcome the shortcoming of this service. The access control model is represented by a semantic ontology, and a set of two level semantic rules representing platform and application specific policy rules. OJADEAC model is distributed, intelligent, dynamic, context-aware and use reasoning engine to infer access decisions based on ontology knowledge.

  4. A study of multiple access schemes in satellite control network

    Science.gov (United States)

    Mo, Zijian; Wang, Zhonghai; Xiang, Xingyu; Wang, Gang; Chen, Genshe; Nguyen, Tien; Pham, Khanh; Blasch, Erik

    2016-05-01

    Satellite Control Networks (SCN) have provided launch control for space lift vehicles; tracking, telemetry and commanding (TTC) for on-orbit satellites; and, test support for space experiments since the 1960s. Currently, SCNs encounter a new challenge: how to maintain the high reliability of services when sharing the spectrum with emerging commercial services. To achieve this goal, the capability of multiple satellites reception is deserved as an update/modernization of SCN in the future. In this paper, we conducts an investigation of multiple access techniques in SCN scenario, e.g., frequency division multiple access (FDMA) and coded division multiple access (CDMA). First, we introduce two upgrade options of SCN based on FDMA and CDMA techniques. Correspondingly, we also provide their performance analysis, especially the system improvement in spectrum efficiency and interference mitigation. Finally, to determine the optimum upgrade option, this work uses CRISP, i.e., Cost, Risk, Installation, Supportability and Performance, as the baseline approach for a comprehensive trade study of these two options. Extensive numerical and simulation results are presented to illustrate the theoretical development.

  5. Consumer Satisfaction with Telerehabilitation Service Provision of Alternative Computer Access and Augmentative and Alternative Communication.

    Science.gov (United States)

    Lopresti, Edmund F; Jinks, Andrew; Simpson, Richard C

    2015-01-01

    Telerehabilitation (TR) services for assistive technology evaluation and training have the potential to reduce travel demands for consumers and assistive technology professionals while allowing evaluation in more familiar, salient environments for the consumer. Sixty-five consumers received TR services for augmentative and alternative communication or alternative computer access, and consumer satisfaction was compared with twenty-eight consumers who received exclusively in-person services. TR recipients rated their TR services at a median of 6 on a 6-point Likert scale TR satisfaction questionnaire, although individual responses did indicate room for improvement in the technology. Overall satisfaction with AT services was rated highly by both in-person (100% satisfaction) and TR (99% satisfaction) service recipients.

  6. Analysis of an FBMC/OQAM scheme for asynchronous access in wireless communications

    Science.gov (United States)

    Mattera, Davide; Tanda, Mario; Bellanger, Maurice

    2015-12-01

    The OFDM/OQAM transceiver belongs to the filter-bank-based multicarrier (FBMC) family and, unlike OFDM schemes, it is particularly able to meet the requirements of the physical layer of cognitive radio networks such as high level of adjacent channel leakage ratio and asynchronous communications. The paper proposes and analyzes a new implementation structure, named frequency spreading, for the OFDM/OQAM transceiver. On flat channels, it is equivalent to the standard one in terms of input-output relations, though more complex. On multipath channels, it offers a crucial advantage in terms of equalization, which is performed in the frequency domain, leading to high performance and no additional delay. With its flexibility and level of performance, the analyzed scheme has the potential to outperform OFDM in the asynchronous access context and in cognitive radio networks.

  7. Effectiveness of Space-Division Multiple-Access in MIMO Communication Systems with Parallel Data Transmission

    Science.gov (United States)

    Ermolayev, V. T.; Flaksman, A. G.; Averin, I. M.; Gribov, D. V.

    2004-02-01

    We consider multiple-input multiple-output (MIMO) cellular communication systems with antenna arrays at both link ends and data transmission via parallel eigenchannels matched with a random spatial channel. We analyze the effectiveness of the space-division multiple-access (SDMA) method, which does not require estimation of signal-arrival directions and is based on orthogonalization of the parallel channels of all users. We obtained approximate analytical expressions for the mean ratio of the signal power to the noise power and the MIMO system capacity, which are derived for the case of Rayleigh fading of signals. Although the obtained formulas are much simpler than the exact ones, they ensure high accuracy for an arbitrary number of transmitting and receiving antennas and an arbitrary power of transmitter. Our results demonstrate the high effectiveness of the proposed SDMA method.

  8. Control and Communication in Provider-Patient Relationships.

    Science.gov (United States)

    Northouse, Peter G.

    Noting that loss of control is a major concern confronting patients experiencing an illness, this paper critically analyzes the research literature on control and clarifies the implications of this research for provider-patient communication. The paper first defines control, noting that the most frequently cited definition is the "locus of…

  9. Access Control Model for Sharing Composite Electronic Health Records

    Science.gov (United States)

    Jin, Jing; Ahn, Gail-Joon; Covington, Michael J.; Zhang, Xinwen

    The adoption of electronically formatted medical records, so called Electronic Health Records (EHRs), has become extremely important in healthcare systems to enable the exchange of medical information among stakeholders. An EHR generally consists of data with different types and sensitivity degrees which must be selectively shared based on the need-to-know principle. Security mechanisms are required to guarantee that only authorized users have access to specific portions of such critical record for legitimate purposes. In this paper, we propose a novel approach for modelling access control scheme for composite EHRs. Our model formulates the semantics and structural composition of an EHR document, from which we introduce a notion of authorized zones of the composite EHR at different granularity levels, taking into consideration of several important criteria such as data types, intended purposes and information sensitivities.

  10. A Hybrid Networking Model for the Access Layer of the Communication Network for Distribution in Smart Grid

    Directory of Open Access Journals (Sweden)

    Wang Hao

    2016-01-01

    Full Text Available The access layer in the communication network for distribution is an important link in the automation of smart distribution power grid. In current access layer of communication network for distribution in Chinese power grid systems, several communication methods like optical fiber, mediumvoltage carrier communication, 1.8GHz TD-LTE power private wireless network, 230MHz TD-LTE power private wireless network, public wireless network are constructed concurrently and running simultaneously in an identical power supply area. This traditional networking model will cause repeated construction and operation and maintenance difficulties in the communication network of power grid. On the basis of giving a detailed analysis of the radio link budget of TD-LTE power private wireless network in two frequencies, this paper present a multi-communication methods hybrid networking model, which gives a clear boundary for different communication methods based on the isoline with equal signal strength of the TD-LTE power private wireless network and accomplish the optimization of communication resources for distribution.

  11. A comparison of breast cancer secondary prevention activities and satisfaction with access and communication issues in women 50 and over.

    Science.gov (United States)

    Roberts, R A; Birch, N J

    2001-04-01

    Between 1950 and 1990, the incidence of breast cancer increased about 52% and the mortality rate increased 4%. Prevention programs (mammograms and clinical breast exams) can positively affect both cost control and mortality rates. Balancing the costs of preventive screening against the potential savings is a part of an ongoing debate centering on the age at which women should have yearly mammograms. Yet, if all agencies agree that women aged 50 and over should receive yearly mammograms, then why are so many women aged 50 and over not being screened? Using previously validated instruments, this study surveyed residents of Spokane County, Washington. Respondents (1,850 returned of 2,600) were compared over time by demographic characteristics and by insurance type to identify any significant differences between those who had preventative screens and those who did not. Issues involving access to screening and communication with healthcare providers were also examined. Factors that affect whether women receive preventative screening include insurance type, provider type, long waiting times, and poor communication among the doctor, the staff, and the patient. The most important determinant to whether preventative screening is being conducted is the relationship between the patient and their healthcare provider. Copyright 2001 American Health Foundation and Academic Press.

  12. Color coded multiple access scheme for bidirectional multiuser visible light communications in smart home technologies

    Science.gov (United States)

    Tiwari, Samrat Vikramaditya; Sewaiwar, Atul; Chung, Yeon-Ho

    2015-10-01

    In optical wireless communications, multiple channel transmission is an attractive solution to enhancing capacity and system performance. A new modulation scheme called color coded multiple access (CCMA) for bidirectional multiuser visible light communications (VLC) is presented for smart home applications. The proposed scheme uses red, green and blue (RGB) light emitting diodes (LED) for downlink and phosphor based white LED (P-LED) for uplink to establish a bidirectional VLC and also employs orthogonal codes to support multiple users and devices. The downlink transmission for data user devices and smart home devices is provided using red and green colors from the RGB LEDs, respectively, while uplink transmission from both types of devices is performed using the blue color from P-LEDs. Simulations are conducted to verify the performance of the proposed scheme. It is found that the proposed bidirectional multiuser scheme is efficient in terms of data rate and performance. In addition, since the proposed scheme uses RGB signals for downlink data transmission, it provides flicker-free illumination that would lend itself to multiuser VLC system for smart home applications.

  13. Attitude Control Subsystem for the Advanced Communications Technology Satellite

    Science.gov (United States)

    Hewston, Alan W.; Mitchell, Kent A.; Sawicki, Jerzy T.

    1996-01-01

    This paper provides an overview of the on-orbit operation of the Attitude Control Subsystem (ACS) for the Advanced Communications Technology Satellite (ACTS). The three ACTS control axes are defined, including the means for sensing attitude and determining the pointing errors. The desired pointing requirements for various modes of control as well as the disturbance torques that oppose the control are identified. Finally, the hardware actuators and control loops utilized to reduce the attitude error are described.

  14. Evaluation of secure capability-based access control in the M2M local cloud platform

    DEFF Research Database (Denmark)

    Anggorojati, Bayu; Prasad, Neeli R.; Prasad, Ramjee

    2016-01-01

    of multiple distributed M2M gateways, creating new challenges in the access control. Some existing access control systems lack in scalability and flexibility to manage access from users or entity that belong to different authorization domains, or fails to provide fine grained and flexible access right...... delegation. Recently, the capability based access control has been considered as method to manage access in the Internet of Things (IoT) or M2M domain. In this paper, the implementation and evaluation of a proposed secure capability based access control in the M2M local cloud platform is presented...

  15. Tuberculosis comorbidity with communicable and non-communicable diseases: integrating health services and control efforts.

    Science.gov (United States)

    Marais, Ben J; Lönnroth, Knut; Lawn, Stephen D; Migliori, Giovanni Battista; Mwaba, Peter; Glaziou, Philippe; Bates, Matthew; Colagiuri, Ruth; Zijenah, Lynn; Swaminathan, Soumya; Memish, Ziad A; Pletschette, Michel; Hoelscher, Michael; Abubakar, Ibrahim; Hasan, Rumina; Zafar, Afia; Pantaleo, Guiseppe; Craig, Gill; Kim, Peter; Maeurer, Markus; Schito, Marco; Zumla, Alimuddin

    2013-05-01

    Recent data for the global burden of disease reflect major demographic and lifestyle changes, leading to a rise in non-communicable diseases. Most countries with high levels of tuberculosis face a large comorbidity burden from both non-communicable and communicable diseases. Traditional disease-specific approaches typically fail to recognise common features and potential synergies in integration of care, management, and control of non-communicable and communicable diseases. In resource-limited countries, the need to tackle a broader range of overlapping comorbid diseases is growing. Tuberculosis and HIV/AIDS persist as global emergencies. The lethal interaction between tuberculosis and HIV coinfection in adults, children, and pregnant women in sub-Saharan Africa exemplifies the need for well integrated approaches to disease management and control. Furthermore, links between diabetes mellitus, smoking, alcoholism, chronic lung diseases, cancer, immunosuppressive treatment, malnutrition, and tuberculosis are well recognised. Here, we focus on interactions, synergies, and challenges of integration of tuberculosis care with management strategies for non-communicable and communicable diseases without eroding the functionality of existing national programmes for tuberculosis. The need for sustained and increased funding for these initiatives is greater than ever and requires increased political and funder commitment. Copyright © 2013 World Health Organization. Published by Elsevier Ltd/Inc/BV. All rights reserved. Published by Elsevier Ltd. All rights reserved.

  16. Strategic use of communication to market cancer prevention and control to vulnerable populations.

    Science.gov (United States)

    Kreps, Gary L

    2008-01-01

    There are significant challenges to communicating relevant cancer prevention and control information to health care consumers due both to the complexities of the health information to be communicated and the complexities of health communication, especially with vulnerable populations. The need for effective communication about cancer risks, early detection, prevention, care, and survivorship is particularly acute, yet also tremendously complex, for reaching vulnerable populations, those groups of people who are most likely to suffer significantly higher levels of morbidity and mortality from cancers than other segments of the population. These vulnerable populations, typically the poorest, lowest educated, and most disenfranchised members of modern society, are heir to serious cancer-related health disparities. Vulnerable populations often have health literacy difficulties, cultural barriers, and economic challenges to accessing and making sense of relevant health information. This paper examines these challenges to communicating relevant information to vulnerable populations and suggests strategies for effectively using different communication media for marketing cancer prevention and control to reduce health disparities and promote public health.

  17. Admission Control and Interference Management in Dynamic Spectrum Access Networks

    Directory of Open Access Journals (Sweden)

    Jorge Martinez-Bauset

    2010-01-01

    Full Text Available We study two important aspects to make dynamic spectrum access work in practice: the admission policy of secondary users (SUs to achieve a certain degree of quality of service and the management of the interference caused by SUs to primary users (PUs. In order to limit the forced termination probability of SUs, we evaluate the Fractional Guard Channel reservation scheme to give priority to spectrum handovers over new arrivals. We show that, contrary to what has been proposed, the throughput of SUs cannot be maximized by configuring the reservation parameter. We also study the interference caused by SUs to PUs. We propose and evaluate different mechanisms to reduce the interference, which are based on simple spectrum access algorithms for both PUs and SUs and channel repacking algorithms for SUs. Numerical results show that the reduction can be of one order of magnitude or more with respect to the random access case. Finally, we propose an adaptive admission control scheme that is able to limit simultaneously the forced termination probability of SUs and what we define as the probability of interference. Our scheme does not require any configuration parameters beyond the probability objectives. Besides, it is simple to implement and it can operate with any arrival process and distribution of the session duration.

  18. Unmanned Aircraft System Control and ATC Communications Bandwidth Requirements

    Science.gov (United States)

    Henriksen, Steve

    2008-01-01

    There are significant activities taking place to establish the procedures and requirements for safe and routine operation of unmanned aircraft systems (UAS) in the National Airspace System (NAS). Among the barriers to overcome in achieving this goal is the lack of sufficient frequency spectrum necessary for the UAS control and air traffic control (ATC) communications links. This shortcoming is compounded by the fact that the UAS control communications links will likely be required to operate in protected frequency spectrum, just as ATC communications links are, because they relate to "safety and regularity of flight." To support future International Telecommunications Union (ITU) World Radio Conference (WRC) agenda items concerning new frequency allocations for UAS communications links, and to augment the Future Communications Study (FCS) Technology Evaluation Group efforts, NASA Glenn Research Center has sponsored a task to estimate the UAS control and ATC communications bandwidth requirements for safe, reliable, and routine operation of UAS in the NAS. This report describes the process and results of that task. The study focused on long-term bandwidth requirements for UAS approximately through 2030.

  19. Efficient identity management and access control in cloud environment

    Science.gov (United States)

    Gloster, Jonathan

    2013-05-01

    As more enterprises are enticed to move data to a cloud environment to enhance data sharing and reduce operating costs by exploiting shared resources, concerns have risen over the ability to secure information within the cloud. This paper examines how a traditional Identity and Access Control (IDAM) architecture can be adapted to address security concerns of a cloud environment. We propose changing the paradigm of IDAM form a pure trust model to a risk based model will enable information to be protected securely in a cloud environment without impacting efficiencies of cloud environments.

  20. Communications for Coordinative Control of Wind Power Systems

    DEFF Research Database (Denmark)

    Wei, Mu

    . The performances of FSWT and DFIG connected DGS are compared and analysed. At last, the cyber security study is presented, due to the important place of security in power system communications. A security domain model is proposed to guide the implementation of the security technologies. Cyber security related...... system control strategies for wind power integration, in order to achieve coordinative control for a secure and efficient power system. The project basically contains three main aspects: studies on DGS (Distributed Generation System) characteristics, analysis of communication technologies...... simulation results reveal the important impact of the security configuration on improving the performance of the associated electric power system data communication systems. This PhD study explores a new aspect of the investigations of wind power system components characteristics, from communication...

  1. Stabilization of Networked Control Systems: Designing Effective Communication Sequences

    Science.gov (United States)

    2004-01-01

    IEEE Transactions on Automatic Control 45(7), 1279–1289. Elia, N. and S. K. Mitter (2001). Stabilization...of linear systems with limited information. IEEE Transactions on Automatic Control 46(9), 1384–1400. Hristu-Varsakelis, D. (2001). Feedback control...and R. W. Brockett (1997). Sys- tems with finite communication bandwidth constraints. i. state estimation problems.. IEEE Transactions on Automatic Control

  2. Optimization of Communication for Commanding and Controlling Systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper mainly discussed some special requiremen ts for communication system and specific implement methods during the cause of cam paign cooperation in modern times. That system is the Advanced Field Tactical Da ta System which was developed to meet the requirements for controlling every fir e nodes, through which Army can achieve their campaign and tactical goals. The c ourse of dealing with communication message mainly include Emery's situation rep orted, Message change (generally referred to taxis a...

  3. Robust Broadcast-Communication Control of Electric Vehicle Charging

    CERN Document Server

    Turitsyn, Konstantin; Backhaus, Scott; Chertkov, Misha

    2010-01-01

    The anticipated increase in the number of plug-in electric vehicles (EV) will put additional strain on electrical distribution circuits. Many control schemes have been proposed to control EV charging. Here, we develop control algorithms based on randomized EV charging start times and simple one-way broadcast communication allowing for a time delay between communication events. Using arguments from queuing theory and statistical analysis, we seek to maximize the utilization of excess distribution circuit capacity while keeping the probability of a circuit overload negligible.

  4. Robust broadcast-communication control of electric vehicle charging

    Energy Technology Data Exchange (ETDEWEB)

    Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Sulc, Petr [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory

    2010-01-01

    The anticipated increase in the number of plug-in electric vehicles (EV) will put additional strain on electrical distribution circuits. Many control schemes have been proposed to control EV charging. Here, we develop control algorithms based on randomized EV charging start times and simple one-way broadcast communication allowing for a time delay between communication events. Using arguments from queuing theory and statistical analysis, we seek to maximize the utilization of excess distribution circuit capacity while keeping the probability of a circuit overload negligible.

  5. An extended smart utilization medium access control (ESU-MAC) protocol for ad hoc wireless systems

    Science.gov (United States)

    Vashishtha, Jyoti; Sinha, Aakash

    2006-05-01

    The demand for spontaneous setup of a wireless communication system has increased in recent years for areas like battlefield, disaster relief operations etc., where a pre-deployment of network infrastructure is difficult or unavailable. A mobile ad-hoc network (MANET) is a promising solution, but poses a lot of challenges for all the design layers, specifically medium access control (MAC) layer. Recent existing works have used the concepts of multi-channel and power control in designing MAC layer protocols. SU-MAC developed by the same authors, efficiently uses the 'available' data and control bandwidth to send control information and results in increased throughput via decreasing contention on the control channel. However, SU-MAC protocol was limited for static ad-hoc network and also faced the busy-receiver node problem. We present the Extended SU-MAC (ESU-MAC) protocol which works mobile nodes. Also, we significantly improve the scheme of control information exchange in ESU-MAC to overcome the busy-receiver node problem and thus, further avoid the blockage of control channel for longer periods of time. A power control scheme is used as before to reduce interference and to effectively re-use the available bandwidth. Simulation results show that ESU-MAC protocol is promising for mobile, ad-hoc network in terms of reduced contention at the control channel and improved throughput because of channel re-use. Results show a considerable increase in throughput compared to SU-MAC which could be attributed to increased accessibility of control channel and improved utilization of data channels due to superior control information exchange scheme.

  6. Cryptanalysis and improvement of controlled secure direct communication

    Institute of Scientific and Technical Information of China (English)

    Kao Shih-Hung; Hwang Tzonelih

    2013-01-01

    This paper points out that,due to a flaw in the sender's encoding,the receiver in Gao et al.'s controlled quantum secret direct communication (CQSDC) protocol [Chin.Phys.14 (2005),No.5,p.893] can reveal the whole secret message without permission from the controller.An improvement is proposed to avoid this flaw.

  7. Minimizing communication cost among distributed controllers in software defined networks

    Science.gov (United States)

    Arlimatti, Shivaleela; Elbreiki, Walid; Hassan, Suhaidi; Habbal, Adib; Elshaikh, Mohamed

    2016-08-01

    Software Defined Networking (SDN) is a new paradigm to increase the flexibility of today's network by promising for a programmable network. The fundamental idea behind this new architecture is to simplify network complexity by decoupling control plane and data plane of the network devices, and by making the control plane centralized. Recently controllers have distributed to solve the problem of single point of failure, and to increase scalability and flexibility during workload distribution. Even though, controllers are flexible and scalable to accommodate more number of network switches, yet the problem of intercommunication cost between distributed controllers is still challenging issue in the Software Defined Network environment. This paper, aims to fill the gap by proposing a new mechanism, which minimizes intercommunication cost with graph partitioning algorithm, an NP hard problem. The methodology proposed in this paper is, swapping of network elements between controller domains to minimize communication cost by calculating communication gain. The swapping of elements minimizes inter and intra communication cost among network domains. We validate our work with the OMNeT++ simulation environment tool. Simulation results show that the proposed mechanism minimizes the inter domain communication cost among controllers compared to traditional distributed controllers.

  8. Advent of Biometric Sensors in Field of Access Control

    Directory of Open Access Journals (Sweden)

    Ali Anas

    2015-09-01

    Full Text Available Biometrics is the science of measuring and analyzing biological data. It is used to uniquely identify individuals by their physical characteristics or personal behavior traits.The results from scrutiny of various themes including unimodal, multimodal, physiological, behavioural bio-metrics. Bio-metrics, Physiological and behavioural are compared in the review. The article addresses a particular aspect of utilizing biometrics for authentication, identification and access control. The use of systems like fingerprint, face recognition, hand geometry, Palm print, DNA analysis, iris recognition, retina and odour/scent will be dealt with herewith. This study deals with various applications of this technology, like surveillance, employee identification, device access etc with mentions respective of hardware used. The influence of such features is yet to be documented properly, but it is safe to say that it has been a huge step towards better information security and identification control.Over the course of this text, we will try to bring to light our analysis of the subject and provide an in-depth examination of contemporary and futuristic technologies pertaining to this field.

  9. Pharma Pricing & Market Access Europe 2016--Health Network Communications' Tenth Annual Conference (February 23-25, 2016--London, UK).

    Science.gov (United States)

    D'Souza, P

    2016-03-01

    Tighter national budgets and escalating drug prices continue to present challenges for pharmaceutical market access strategies and societal cost of care. As pharmaceutical companies and medical governmental advisory organizations enter tougher negotiations, hospital trusts and other dispensary firms face barriers to receiving the best medical treatment, and as a result patient access is limited. The 2016 HealthNetwork Communications' Pharma Pricing & Market Access Europe meeting brought together pharmaceutical, medical governmental advisory and stakeholders and market access/pricing consultants, to encourage discussions and negotiations into how to improve the drug pricing system and consequential market access strategies while achieving the respective reimbursement and affordability objectives. Copyright 2016 Prous Science, S.A.U. or its licensors. All rights reserved.

  10. Students' Perceptions of Part-time and Tenured/Tenure-Track Faculty: Accessibility, Mentoring, and Extra-Class Communication.

    Science.gov (United States)

    Bippus, Amy M.; Brooks, Catherine F.; Plax, Timothy G.; Kearney, Patricia

    2001-01-01

    Gives an overview of the differences between part-time and tenured/tenure-track faculty members, with particular attention to how these differences may impact students' perceptions of instructors' accessibility. Introduces the construct of extra-class communication (EEC) and explores how faculty employment status of instructors may affect…

  11. Scholarly Publishing's Evolving Landscape: Impact Metrics, Electronic-Only Journals, and Open Access in Journalism and Communication Research

    Science.gov (United States)

    Antell, Karen; Foote, Joe S.; Foote, Jody Bales

    2016-01-01

    This study surveys the landscape of scholarly publishing, with particular emphasis on scholarly journals in the communication discipline, measuring the shift to electronic publishing in six selected disciplines and exploring two other important emerging topics: open-access publishing and new journal citation metrics. The goals are to inform…

  12. Typography for Graphic Communication [and] Typographic Access Structures for Educational Texts [and] Graphic Aspects of Complex Texts: Typography as Macropunctuation.

    Science.gov (United States)

    Waller, Robert

    The three papers included in this report address typography for graphic communication, typographic access structures for educational texts, and typography as macropunctuation. The first paper considers the consequences of an aesthetic bias in the literature of typography, and identifies two misleading assumptions about textbooks; i.e., that print…

  13. I/O Standard Based Thermal/Energy Efficient Green Communication For Wi-Fi Protected Access on FPGA

    DEFF Research Database (Denmark)

    Kumar, Tanesh; Pandey, Bishwajeet; Das, Teerath

    2014-01-01

    be generated with Fibonacci generator. Here, thermal efficient green Fibonacci Generator is used to generate key for Wi-Fi Protected Access in order to make green communication possible under different room temperature. By analysis it is observed that at standard normal temperature (21degrees C), LVCMOS12 have...

  14. Typography for Graphic Communication [and] Typographic Access Structures for Educational Texts [and] Graphic Aspects of Complex Texts: Typography as Macropunctuation.

    Science.gov (United States)

    Waller, Robert

    The three papers included in this report address typography for graphic communication, typographic access structures for educational texts, and typography as macropunctuation. The first paper considers the consequences of an aesthetic bias in the literature of typography, and identifies two misleading assumptions about textbooks; i.e., that print…

  15. 2011 International Conference in Electrics, Communication and Automatic Control Proceedings

    CERN Document Server

    2012-01-01

    This two-volume set contains the very latest, cutting-edge material in electrics, communication and automatic control. As a vital field of research that is highly relevant to current developments in a number of technological domains, the subjects it covers include micro-electronics and integrated circuit control, signal processing technology, next-generation network infrastructure, wireless communication and scientific instruments. The aim of the International Conference in Electrics, Communication and Automatic Control, held in Chongqing, China, in June 2011 was to provide a valuable inclusive platform for researchers, engineers, academicians and industrial professionals from all over the world to share their research results with fellow scientists in the sector. The call for papers netted well over 600 submissions, of which 224 were selected for presentation. This fully peer-reviewed collection of papers from the conference can be viewed as a single-source compendium of the latest trends and techniques in t...

  16. Plastic optical fiber serial communications link for distributed control system

    Science.gov (United States)

    Saxena, Piyush; Sharangpani, K. K.; Vora, H. S.; Nakhe, S. V.; Jain, R.; Shenoy, N. M.; Bhatnagar, R.; Shirke, N. D.

    2001-09-01

    One of the most common interface for communications specified is RS 232C standard. Though widely accepted, RS232 has limited transmission speed, range and networking capabilities. RS 422 standard overcomes limitations by using differential signal lines. In automation of the operation of gas discharge lasers, multiple processors are used for control of lasers, cooling system, vacuum system etc. High EMI generated by lasers interfere through galvanic transmission or by radiation over the length of cables, and hang up operation of processors or control PC. A serial communications link was designed eliminating copper transmission media, using plastic optical fiber cables and components, to connect local controllers with the master PC working on RS232 protocols. The paper discusses the design and implementation of a high ly reliable EMI harden serial communications link.

  17. A new method for chaos control in communication systems

    Energy Technology Data Exchange (ETDEWEB)

    Lin, S.-L. [Department of Mechanical Engineering, National Central University, No. 300, Jhongda Rd., Jhongli City, Taoyuan County 32001, Taiwan (China); Tung, P.-C. [Department of Mechanical Engineering, National Central University, No. 300, Jhongda Rd., Jhongli City, Taoyuan County 32001, Taiwan (China)], E-mail: t331166@ncu.edu.tw

    2009-12-15

    With the increasing needs of global communication, the improvement of secure communication is of vital importance. This study proposes a new scheme for establishing secure communication systems. The new scheme separates white Gaussian noises from the chaotic signals with modified Independent Component Analysis (ICA) and then controls each chaotic signal. This scheme is able to deal with white Gaussian noises in the natural world. However, the signals separated by traditional ICA shows opposite phase and unequal amplitude, making chaos control impossible. Our study proposed a modified ICA, which can calculate accurately the phase and amplitude and ensure control of the chaotic systems. The result indicates that our proposed system can successfully separate white Gaussian noise and stabilize all the chaotic signals.

  18. Exploring Bridge-Engine Control Room Collaborative Team Communication

    Directory of Open Access Journals (Sweden)

    Aditi Kataria

    2015-06-01

    Full Text Available The EC funded CyClaDes research project is designed to promote the increased impact of the human element in shipping across the design and operational lifecycle. It addresses the design and operation of ships and ship systems. One of the CyClaDes’ tasks is to create a crew-centered design case-study examination of the information that is shared between the Bridge and Engine Control Room that helps the crew co-ordinate to ensure understanding and complete interconnected tasks. This information can be provided in various ways, including communication devices or obtained from a common database, display, or even the ship environment (e.g., the roll of the ship. A series of semi-structured interviews were conducted with seafarers of diverse ranks to get a better idea of what communication does, or should, take place and any problems or challenges existing in current operations, as seen from both the bridge and ECR operators’ perspectives. Included in the interview were both the standard communications and information shared during planning and executing a voyage, as well as special situations such as safety/casualty tasks or heavy weather. The results were analyzed in terms of the goals of the communication, the primary situations of interest for communication and collaboration, the communication media used, the information that is shared, and the problems experienced. The results of seafarer interviews are presented in the paper to explore on-board inter-departmental communication.

  19. 78 FR 51810 - Twenty-Fourth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-08-21

    ... Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control... RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held...

  20. 76 FR 50811 - Eighth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-08-16

    ... Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 224: Airport Security Access Control...

  1. 77 FR 25525 - Thirteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems.

    Science.gov (United States)

    2012-04-30

    ... Access Control Systems. AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems... Committee 224, Airport Security Access Control Systems DATES: The meeting will be held May 30, 2012, from...

  2. Error control and channel access technique of the computer-based truck dispatching system in the open-pit mine

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, G.; Wang, Y.; Huang, Z. [China University of Mining and Technology (China)

    1994-06-01

    The disposition of hardware and software of a computer-based truck dispatching system for open-pit mine are described in the paper. The advantages of random channel access technique of the CSMA/CA/CD of the SWARQ error control and of encoding of constant proportion code were proved by theoretical analysis. The block diagram of the main communication software is given. 3 refs., 4 figs.

  3. Wireless communication technology for modular mechatronic controllers

    CSIR Research Space (South Africa)

    Bright, G

    2010-08-01

    Full Text Available )h(u,,hu,,hxx ?+???+???+?= ?+ 5.17 7 For a MIMO system with m sensors and n actuators, the system equations are: ( ) ( ) ( ) ( )tttt vuBxAx ++=? 5.18 where A and B are now matrices. The longest sensor to controller delay is defined as: ( )scmk2sck1scksck ,...,,max....16 can be sampled into: k1k can k 1ca k sc kk can k 1ca k sc kk1k ,...,,,...,, vu?u??xx 10 +?????? ???+?????? ???+= ?+ 5.21 where xk = x(kh), heA? = 5.22 ?? ??? ? ?????? ????????? ???=?????? ??? can k sc k n 0 1ca k sc k...

  4. Efficient Quantum Private Communication Based on Dynamic Control Code Sequence

    Science.gov (United States)

    Cao, Zheng-Wen; Feng, Xiao-Yi; Peng, Jin-Ye; Zeng, Gui-Hua; Qi, Jin

    2016-12-01

    Based on chaos and quantum properties, we propose a quantum private communication scheme with dynamic control code sequence. The initial sequence is obtained via chaotic systems, and the control code sequence is derived by grouping, XOR and extracting. A shift cycle algorithm is designed to enable the dynamic change of control code sequence. Analysis shows that transmission efficiency could reach 100 % with high dynamics and security.

  5. Efficient Quantum Private Communication Based on Dynamic Control Code Sequence

    Science.gov (United States)

    Cao, Zheng-Wen; Feng, Xiao-Yi; Peng, Jin-Ye; Zeng, Gui-Hua; Qi, Jin

    2017-04-01

    Based on chaos and quantum properties, we propose a quantum private communication scheme with dynamic control code sequence. The initial sequence is obtained via chaotic systems, and the control code sequence is derived by grouping, XOR and extracting. A shift cycle algorithm is designed to enable the dynamic change of control code sequence. Analysis shows that transmission efficiency could reach 100 % with high dynamics and security.

  6. Task-role-based Access Control Model in Smart Health-care System

    Directory of Open Access Journals (Sweden)

    Wang Peng

    2015-01-01

    Full Text Available As the development of computer science and smart health-care technology, there is a trend for patients to enjoy medical care at home. Taking enormous users in the Smart Health-care System into consideration, access control is an important issue. Traditional access control models, discretionary access control, mandatory access control, and role-based access control, do not properly reflect the characteristics of Smart Health-care System. This paper proposes an advanced access control model for the medical health-care environment, task-role-based access control model, which overcomes the disadvantages of traditional access control models. The task-role-based access control (T-RBAC model introduces a task concept, dividing tasks into four categories. It also supports supervision role hierarchy. T-RBAC is a proper access control model for Smart Health-care System, and it improves the management of access rights. This paper also proposes an implementation of T-RBAC, a binary two-key-lock pair access control scheme using prime factorization.

  7. Robust Relay in Narrow-Band Communications for Ubiquitous IoT Access

    Directory of Open Access Journals (Sweden)

    Qinghe Du

    2017-01-01

    Full Text Available We propose a robust wireless relay scheme in narrow-band communications for IoT access, which matches the typical features of IoT often carrying relatively low data rate with limited bandwidth. This framework is towards offering robustness in QoS guarantees with emphases on security and/or reliability, and we use the security-assured network as the typical scenario. In particular, we consider a dual-hop relay network including a transmitter, a receiver, an amplify-and-forward (AF untrusted relay, and a jamming node. The jamming node is treated as a helper. Specifically, the jammer broadcasts artificial noise (AN, which in fact pollutes both the untrusted relay and the destination node’s signals. However, we show that such AN can be effectively mitigated after the destination node obtains the forwarded signal from the relay, while the untrusted relay node cannot do so. The core idea for robustness assurance is to exploit higher signal dimensions at the receiver over the untrusted relay node. Simulations and analyses are also conducted to demonstrate that our proposed scheme can make the performance at the untrusted relay an interference-limited manner while completely removing the interferences at the receiver, therefore corroborating our claim in robustness in terms of security and reliability.

  8. Resource allocation in shared spectrum access communications for operators with diverse service requirements

    Science.gov (United States)

    Kibria, Mirza Golam; Villardi, Gabriel Porto; Ishizu, Kentaro; Kojima, Fumihide; Yano, Hiroyuki

    2016-12-01

    In this paper, we study inter-operator spectrum sharing and intra-operator resource allocation in shared spectrum access communication systems and propose efficient dynamic solutions to address both inter-operator and intra-operator resource allocation optimization problems. For inter-operator spectrum sharing, we present two competent approaches, namely the subcarrier gain-based sharing and fragmentation-based sharing, which carry out fair and flexible allocation of the available shareable spectrum among the operators subject to certain well-defined sharing rules, traffic demands, and channel propagation characteristics. The subcarrier gain-based spectrum sharing scheme has been found to be more efficient in terms of achieved throughput. However, the fragmentation-based sharing is more attractive in terms of computational complexity. For intra-operator resource allocation, we consider resource allocation problem with users' dissimilar service requirements, where the operator supports users with delay constraint and non-delay constraint service requirements, simultaneously. This optimization problem is a mixed-integer non-linear programming problem and non-convex, which is computationally very expensive, and the complexity grows exponentially with the number of integer variables. We propose less-complex and efficient suboptimal solution based on formulating exact linearization, linear approximation, and convexification techniques for the non-linear and/or non-convex objective functions and constraints. Extensive simulation performance analysis has been carried out that validates the efficiency of the proposed solution.

  9. Adaptive Media Access Control for Energy Harvesting - Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Dragoni, Nicola

    2012-01-01

    ODMAC (On-Demand Media Access Control) is a recently proposed MAC protocol designed to support individual duty cycles for Energy Harvesting — Wireless Sensor Networks (EH-WSNs). Individual duty cycles are vital for EH-WSNs, because they allow nodes to adapt their energy consumption to the ever......-changing environmental energy sources. In this paper, we present an improved and extended version of ODMAC and we analyze it by means of an analytical model that can approximate several performance metrics in an arbitrary network topology. The simulations and the analytical experiments show ODMAC's ability to satisfy...... three key properties of EH-WSNs: adaptability of energy consumption, distributed energy-aware load balancing and support for different application-specific requirements....

  10. Generalized access control strategies for integrated services token passing systems

    Science.gov (United States)

    Pang, Joseph W. M.; Tobagi, Fouad A.; Boyd, Stephen

    1994-08-01

    The demand for integrated services local area networks is increasing at a rapid pace with the advent of many new and exciting applications: office and factory automation, distributed computing, and multimedia communications. To support these new applications, it is imperative to integrate traffic with diverse statistical characteristics and differing delay requirements on the same network. An attractive approach for integrating traffic has been adopted in two token passing local area network standards, the IEEE 802.4 token bus standard and FDDI. The idea is to control the transmissions of each station based on a distributed timing algorithm, so as to achieve the following goals: (1) to limit the token cycles so that time-critical traffic can be accommodated, and (2) to allocate pre-specified bandwidths to different stations when the network is overloaded. We have investigated the analysis and design of this protocol. In this paper, we generalize the transmission control algorithm used previously. The major advantages of the generalization over the original protocol are: (1) it provides a much expanded design space, (2) it guarantees convergent behavior, and (3) it gives meaningful insights into the dynamics of the basic control algorithm.

  11. Database Security System for Applying Sophisticated Access Control via Database Firewall Server

    OpenAIRE

    Eun-Ae Cho; Chang-Joo Moon; Dae-Ha Park; Kang-Bin Yim

    2014-01-01

    Database security, privacy, access control, database firewall, data break masking Recently, information leakage incidents have occurred due to database security vulnerabilities. The administrators in the traditional database access control methods grant simple permissions to users for accessing database objects. Even though they tried to apply more strict permissions in recent database systems, it was difficult to properly adopt sophisticated access control policies to commercial databases...

  12. Finite time coordinated formation control for spacecraft formation flying under directed communication topology

    Science.gov (United States)

    Ran, Dechao; Chen, Xiaoqian; Misra, Arun K.

    2017-07-01

    This paper investigates the finite time coordinated formation control problem for spacecraft formation flying (SFF) under the assumption of directed communication topology. By using the neighborhood state measurements, a robust finite time coordinated formation controller is firstly designed based on the nonsingular terminal sliding mode surface. To address the special case that the desired trajectory of the formation is only accessible to a subset of spacecraft in the formation, an adaptive finite time coordinated formation controller is also proposed by designing a novel sliding mode surface. In both cases, the external disturbances are explicitly taken into account. Rigorous theoretical analysis proves that the proposed control schemes ensure that the closed-loop system can track the desired time-varying trajectory in finite time. Numerical simulations are presented that not only highlights the closed-loop performance benefits from the proposed control algorithms, but also illustrates the effectiveness in the presence of external disturbances when compared with the existing coordinated formation control schemes.

  13. Safety systems and access control in the National Ignition Facility.

    Science.gov (United States)

    Reed, Robert K; Bell, Jayce C

    2013-06-01

    The National Ignition Facility (NIF) is the world's largest and most energetic laser system. The facility has the potential to generate ionizing radiation due to the interaction between the laser beams and target material, with neutrons and gamma rays being produced during deuterium-tritium fusion reactions. To perform these experiments, several types of hazards must be mitigated and controlled to ensure personnel safety. NIF uses a real-time safety system to monitor and mitigate the hazards presented by the facility. The NIF facility Safety Interlock System (SIS) monitors for oxygen deficiency and controls access to the facility preventing exposure to laser light and radiation from the Radiation Generating Devices. It also interfaces to radiation monitoring and other radiological monitoring and alarm systems. The SIS controls permissives to the hazard-generating equipment and annunciates hazard levels in the facility. To do this reliably and safely, the SIS has been designed as a fail-safe system with a proven performance record now spanning over 10 y. This paper discusses the SIS, its design, implementation, operator interfaces, validation/verification, and the hazard mitigation approaches employed in the NIF. A brief discussion of the Failure Modes and Effect Analysis supporting the SIS will also be presented. The paper ends with a general discussion of SIS do's and don'ts and common design flaws that should be avoided in SIS design.

  14. Control and Non-Payload Communications Generation 1 Prototype Radio Flight Test Report

    Science.gov (United States)

    Shalkhauser, Kurt A.; Young, Daniel P.; Bretmersky, Steven C.; Ishac, Joseph A.; Walker, Steven H.; Griner, James H.; Kachmar, Brian A.

    2014-01-01

    Unmanned aircraft (UA) represent a new capability that will provide a variety of services in the Government (public) and commercial (civil) aviation sectors. The growth of this potential industry has not yet been realized because of the lack of a common understanding of what is required to safely operate Unmanned Aircraft Systems in the National Airspace System (UAS in the NAS). The desire and ability to fly UA is of increasing urgency. The application of UA to perform national security, defense, scientific, and emergency management are driving the critical need for less restrictive access by UA to the NAS. Existing Federal Aviation Regulations, procedures, and technologies do not allow routine UA access to the NAS. Access to the NAS is hampered by challenges such as the lack of an onboard pilot to see and avoid other aircraft; the ability of a single pilot or operator to control multiple UA; the reliance on command and control (C2) links; the altitudes, speeds, and duration at which the aircraft fly; and the wide variation in UA size and performance. NASA is working with other Government agencies to provide solutions that reduce technical barriers and make access to the NAS routine. This goal will be accomplished through system-level integration of key concepts, technologies, or procedures and through demonstrations of these integrated capabilities in an operationally relevant environment. This project provides an opportunity to transition the acquired empirical data and knowledge to the Federal Aviation Administration and other stakeholders to help them define the requirements for routine UA access to the NAS.Radio communications channels for UA are currently managed through exceptions and use either Department of Defense frequencies for line-of-sight (LOS) and satellite-based communications links, low-power LOS links in amateur bands, or unlicensed Industrial/Scientific/Medical (ISM) frequencies. None of these frequency bands are designated for safety and

  15. A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems.

    Science.gov (United States)

    Choi, Donghee; Kim, Dohoon; Park, Seog

    2015-01-01

    Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment.

  16. Communication Needs Assessment for Distributed Turbine Engine Control

    Science.gov (United States)

    Culley, Dennis E.; Behbahani, Alireza R.

    2008-01-01

    Control system architecture is a major contributor to future propulsion engine performance enhancement and life cycle cost reduction. The control system architecture can be a means to effect net weight reduction in future engine systems, provide a streamlined approach to system design and implementation, and enable new opportunities for performance optimization and increased awareness about system health. The transition from a centralized, point-to-point analog control topology to a modular, networked, distributed system is paramount to extracting these system improvements. However, distributed engine control systems are only possible through the successful design and implementation of a suitable communication system. In a networked system, understanding the data flow between control elements is a fundamental requirement for specifying the communication architecture which, itself, is dependent on the functional capability of electronics in the engine environment. This paper presents an assessment of the communication needs for distributed control using strawman designs and relates how system design decisions relate to overall goals as we progress from the baseline centralized architecture, through partially distributed and fully distributed control systems.

  17. Outbreaks: Sources of Epidemiological Knowledge in Communicable Disease Control

    NARCIS (Netherlands)

    P.L.J.M. Mertens (Paulus Leonardus Johannes Marie)

    2008-01-01

    textabstractPublic health has been defined as the science and art of disease prevention, prolonging life, and promoting health and well-being through organized community effort for the sanitation of the environment, the control of communicable infections, the organization of medical and nursing serv

  18. Outbreaks: Sources of Epidemiological Knowledge in Communicable Disease Control

    NARCIS (Netherlands)

    P.L.J.M. Mertens (Paulus Leonardus Johannes Marie)

    2008-01-01

    textabstractPublic health has been defined as the science and art of disease prevention, prolonging life, and promoting health and well-being through organized community effort for the sanitation of the environment, the control of communicable infections, the organization of medical and nursing

  19. Uplink Power Control For Earth/Satellite/Earth Communication

    Science.gov (United States)

    Chakraborty, Dayamoy

    1994-01-01

    Proposed control subsystem adjusts power radiated by uplink transmitter in Earth station/satellite relay station/ Earth station communication system. Adjustments made to compensate for anticipated changes in attenuation by rain. Raw input is a received downlink beacon singal, amplitude of which affected not only by rain fade but also by scintillation, attenuation in atmospheric gases, and diurnal effects.

  20. Communication, control and security challenges for the smart grid

    CERN Document Server

    Muyeen, SM

    2017-01-01

    The Smart Grid is a modern electricity grid allowing for distributed, renewable intermittent generation, partly owned by consumers. This requires advanced control and communication technologies in order to provide high quality power supply and secure generation, transmission and distribution. This book outlines these emerging technologies.

  1. Research into command, control, and communications in space construction

    Science.gov (United States)

    Davis, Randal

    1990-01-01

    Coordinating and controlling large numbers of autonomous or semi-autonomous robot elements in a space construction activity will present problems that are very different from most command and control problems encountered in the space business. As part of our research into the feasibility of robot constructors in space, the CSC Operations Group is examining a variety of command, control, and communications (C3) issues. Two major questions being asked are: can we apply C3 techniques and technologies already developed for use in space; and are there suitable terrestrial solutions for extraterrestrial C3 problems? An overview of the control architectures, command strategies, and communications technologies that we are examining is provided and plans for simulations and demonstrations of our concepts are described.

  2. Access to hands-on mathematics measurement activities using robots controlled via speech generating devices: three case studies.

    Science.gov (United States)

    Adams, Kim; Cook, Al

    2014-07-01

    To examine how using a robot controlled via a speech generating device (SGD) influences the ways students with physical and communication limitations can demonstrate their knowledge in math measurement activities. Three children with severe physical disabilities and complex communication needs used the robot and SGD system to perform four math measurement lessons in comparing, sorting and ordering objects. The performance of the participants was measured and the process of using the system was described in terms of manipulation and communication events. Stakeholder opinions were solicited regarding robot use. Robot use revealed some gaps in the procedural knowledge of the participants. Access to both the robot and SGD was shown to provide several benefits. Stakeholders thought the intervention was important and feasible for a classroom environment. The participants were able to participate actively in the hands-on and communicative measurement activities and thus meet the demands of current math instruction methods. Current mathematics pedagogy encourages doing hands-on activities while communicating about concepts. Adapted Lego robots enabled children with severe physical disabilities to perform hands-on length measurement activities. Controlling the robots from speech generating devices (SGD) enabled the children, who also had complex communication needs, to reflect and report on results during the activities. By using the robots combined with SGDs, children both exhibited their knowledge of and experienced the concepts of mathematical measurements.

  3. 78 FR 31627 - Twenty-Second Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-05-24

    ...: RTCA Special Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation... 224, Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty-second meeting of the RTCA Special Committee 224, Airport Security Access...

  4. 76 FR 9632 - Fifth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-02-18

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Access Control Systems (Update to DO-230B): Agenda March 10, 2011 Welcome/Introductions/Administrative... Federal Aviation Administration Fifth Meeting: RTCA Special Committee 224: Airport Security Access...

  5. Suction catheter for enhanced control and accuracy of transseptal access.

    Science.gov (United States)

    Sulkin, Matthew S; Berwick, Zachary C; Hermiller, James B; Navia, Jose A; Kassab, Ghassan S

    2016-12-20

    Percutaneous structural heart therapies, such as mitral value repair, require site-specific transseptal access (TSA). This can be challenging for interventional cardiologists. We describe a TSA catheter (TSAC) that utilises suction for enhanced control and puncture accuracy. Here, we aim to evaluate the safety and efficacy of the device. Ex vivo interatrial septum preparations were dissected from swine (n=8) and diseased human hearts (n=6) to quantify TSAC suction and needle puncture force. TSAC suction was 6.5-fold greater than the opposing needle puncture force, and thus provides sufficient stabilisation for punctures. The safety and efficacy of TSAC was evaluated in a chronic mitral regurgitation swine model (n=10) and compared to a conventional TSA device. MR was induced by disrupting one to three mitral chordae tendineae, and the progression of heart disease was followed for three weeks. During device testing, procedure time and fluoroscopy exposure were not statistically different between devices. TSAC reduced septal displacement from 8.7±0.30 mm to 3.60±0.19 mm (p<0.05) and improved puncture accuracy 1.75-fold. TSAC provides controlled TSA and improves puncture accuracy, while maintaining procedure time and workflow. These findings provide a strong rationale for a first-in-man study to demonstrate the clinical utility of the device.

  6. High-speed narrowband PLC - High-performance Access Powerline Communication structures in smart grid; High-Speed Narrowband PLC. Leistungsfaehige Access-Powerline-Kommunikationsstrukturen im Smart Grid

    Energy Technology Data Exchange (ETDEWEB)

    Offner, Georg [devolo AG, Aachen (Germany)

    2012-07-01

    The smart grid provides a stable operation of a decentralized power system which is fed more and more by small providers by means of solar technology and wind power technology. Furthermore, commercial and private clients profit from the smart grid, as they may capture information about their current consumption in real time or can obtain these data from the Internet. The author of the contribution under consideration presents new approaches to access powerline communications that enable efficient communication between IPv6 based household meter and network station. The contribution under consideration describes the technologies used as well as practical experiences and initial results from field tests. Here insights from the integration of G3-PLC are in the foreground.

  7. Spectrum sharing in cognitive radio networks medium access control protocol based approach

    CERN Document Server

    Pandit, Shweta

    2017-01-01

    This book discusses the use of the spectrum sharing techniques in cognitive radio technology, in order to address the problem of spectrum scarcity for future wireless communications. The authors describe a cognitive radio medium access control (MAC) protocol, with which throughput maximization has been achieved. The discussion also includes use of this MAC protocol for imperfect sensing scenarios and its effect on the performance of cognitive radio systems. The authors also discuss how energy efficiency has been maximized in this system, by applying a simple algorithm for optimizing the transmit power of the cognitive user. The study about the channel fading in the cognitive user and licensed user and power adaption policy in this scenario under peak transmit power and interference power constraint is also present in this book.

  8. A novel distributed algorithm for media access control address assignment in wireless sensor networks

    Institute of Scientific and Technical Information of China (English)

    TIAN Ye; SHENG Min; LI Jiandong

    2007-01-01

    This Paper presents a novel distributed media access control(MAC)address assignment algorithm,namely virtual grid spatial reusing(VGSR),for wireless sensor networks,which reduces the size of the MAC address efficiently on the basis of both the spatial reuse of MAC address and the mapping of geographical position.By adjusting the communication range of sensor nodes,VGSR algorithm can minimize the size of MAC address and meanwhile guarantee the connectivity of the sensor network.Theoretical analysis and experimental results show that VGSR algorithm is not only of low energy cost,but also scales well with the network ize,with its performance superior to that of other existing algorithms.

  9. Development of Remote Monitoring and a Control System Based on PLC and WebAccess for Learning Mechatronics

    Directory of Open Access Journals (Sweden)

    Wen-Jye Shyr

    2013-02-01

    Full Text Available This study develops a novel method for learning mechatronics using remote monitoring and control, based on a programmable logic controller (PLC and WebAccess. A mechatronics module, a Web‐CAM and a PLC were integrated with WebAccess software to organize a remote laboratory. The proposed system enables users to access the Internet for remote monitoring and control of the mechatronics module via a web browser, thereby enhancing work flexibility by enabling personnel to control mechatronics equipment from a remote location. Mechatronics control and long‐distance monitoring were realized by establishing communication between the PLC and WebAccess. Analytical results indicate that the proposed system is feasible. The suitability of this system is demonstrated in the department of industrial education and technology at National Changhua University of Education, Taiwan. Preliminary evaluation of the system was encouraging and has shown that it has achieved success in helping students understand concepts and master remote monitoring and control techniques.

  10. Security analysis and improvements of authentication and access control in the Internet of Things.

    Science.gov (United States)

    Ndibanje, Bruce; Lee, Hoon-Jae; Lee, Sang-Gon

    2014-08-13

    Internet of Things is a ubiquitous concept where physical objects are connected over the internet and are provided with unique identifiers to enable their self-identification to other devices and the ability to continuously generate data and transmit it over a network. Hence, the security of the network, data and sensor devices is a paramount concern in the IoT network as it grows very fast in terms of exchanged data and interconnected sensor nodes. This paper analyses the authentication and access control method using in the Internet of Things presented by Jing et al. (Authentication and Access Control in the Internet of Things. In Proceedings of the 2012 32nd International Conference on Distributed Computing Systems Workshops, Macau, China, 18-21 June 2012, pp. 588-592). According to our analysis, Jing et al.'s protocol is costly in the message exchange and the security assessment is not strong enough for such a protocol. Therefore, we propose improvements to the protocol to fill the discovered weakness gaps. The protocol enhancements facilitate many services to the users such as user anonymity, mutual authentication, and secure session key establishment. Finally, the performance and security analysis show that the improved protocol possesses many advantages against popular attacks, and achieves better efficiency at low communication cost.

  11. Secure Communications in High Speed Fiber Optical Networks Using Code Division Multiple Access (CDMA) Transmission

    Energy Technology Data Exchange (ETDEWEB)

    Han, I; Bond, S; Welty, R; Du, Y; Yoo, S; Reinhardt, C; Behymer, E; Sperry, V; Kobayashi, N

    2004-02-12

    This project is focused on the development of advanced components and system technologies for secure data transmission on high-speed fiber optic data systems. This work capitalizes on (1) a strong relationship with outstanding faculty at the University of California-Davis who are experts in high speed fiber-optic networks, (2) the realization that code division multiple access (CDMA) is emerging as a bandwidth enhancing technique for fiber optic networks, (3) the realization that CDMA of sufficient complexity forms the basis for almost unbreakable one-time key transmissions, (4) our concepts for superior components for implementing CDMA, (5) our expertise in semiconductor device processing and (6) our Center for Nano and Microtechnology, which is where the majority of the experimental work was done. Here we present a novel device concept, which will push the limits of current technology, and will simultaneously solve system implementation issues by investigating new state-of-the-art fiber technologies. This will enable the development of secure communication systems for the transmission and reception of messages on deployed commercial fiber optic networks, through the CDMA phase encoding of broad bandwidth pulses. CDMA technology has been developed as a multiplexing technology, much like wavelength division multiplexing (WDM) or time division multiplexing (TDM), to increase the potential number of users on a given communication link. A novel application of the techniques created for CDMA is to generate secure communication through physical layer encoding. Physical layer encoding devices are developed which utilize semiconductor waveguides with fast carrier response times to phase encode spectral components of a secure signal. Current commercial technology, most commonly a spatial light modulator, allows phase codes to be changed at rates of only 10's of Hertz ({approx}25ms response). The use of fast (picosecond to nanosecond) carrier dynamics of semiconductors

  12. Data Access, Ownership, and Control: Toward Empirical Studies of Access Practices.

    Science.gov (United States)

    Hilgartner, Stephen; Brandt-Rauf, Sherry I.

    1994-01-01

    Examines how the new sociology of science can approach data access issues. A perspective is developed based on an analysis of the process of scientific production, data streams, and intellectual policy issues. (Contains 55 references.) (JLB)

  13. Motion synchronization in unmanned aircrafts formation control with communication delays

    Science.gov (United States)

    Rezaee, Hamed; Abdollahi, Farzaneh

    2013-03-01

    This paper proposes a formation control strategy for unmanned aircrafts using a virtual structure. Cross coupled sliding mode controllers are introduced to cope with uncertainties in the attitude measurement systems of the unmanned aircrafts and unmeasurable bounded external disturbances such as wind effects, and also to provide motion synchronization in the multi-agent system. This motion synchronization strategy improves the agents convergence to their desired positions, and this is useful for a multi-agent system with faulty agents. Moreover, the proposed motion synchronization strategy is not restricted to specific communication topologies, and sufficient conditions are provided to guarantee the multi-agent system stability in the presence of communication delays. Numerical simulations are presented for a team of five unmanned aircrafts to make a pentagon formation and confirm the accepted performance of the proposed control strategy.

  14. Communications for Coordinative Control of Wind Power Systems

    DEFF Research Database (Denmark)

    Wei, Mu

    system control strategies for wind power integration, in order to achieve coordinative control for a secure and efficient power system. The project basically contains three main aspects: studies on DGS (Distributed Generation System) characteristics, analysis of communication technologies......, and integration of power system and communication system. For the DGS studies, the main components, such as WTs (Wind Turbines) and CHPs (Combined Head and Power), are modelled. Since WTs are sensitive to disturbances, one focus of this PhD study is the investigation of WTs characteristics; mainly covering FSIG...... (Fixed Speed Induction Generator) and DFIG (Doubly-Fed Induction Generator) based wind turbine systems. Based on the study, the critical points to stabilize FSWTs (Fixed Speed Wind Turbines), after disturbances, are determined. This demands the latency requirements on the possible control and protection...

  15. A Trusted Host's Authentication Access and Control Model Faced on User Action

    Institute of Scientific and Technical Information of China (English)

    ZHANG Miao; XU Guoai; HU Zhengming; YANG Yixian

    2006-01-01

    The conception of trusted network connection (TNC) is introduced, and the weakness of TNC to control user's action is analyzed. After this, the paper brings out a set of secure access and control model based on access, authorization and control, and related authentication protocol. At last the security of this model is analyzed. The model can improve TNC's security of user control and authorization.

  16. The new biometric access control system resembles a big electronic eye. It will be used to control access to the LHC from 2007 onwards.

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The new LHC access control systems will soon be using the latest technology: optical recognition based on iris image data. In order to gain access to the tunnel it will be your eye, not your credentials that you'll be required to show! As of September, the entrance point at Point 8 should be the first to be fitted out with iris recognition equipment. The other access shafts will then gradually be equipped one by one.

  17. How Drug Control Policy and Practice Undermine Access to Controlled Medicines

    Science.gov (United States)

    Csete, Joanne; Wilson, Duncan; Fox, Edward; Wolfe, Daniel; Rasanathan, Jennifer J. K.

    2017-01-01

    Abstract Drug conventions serve as the cornerstone for domestic drug laws and impose a dual obligation upon states to prevent the misuse of controlled substances while ensuring their adequate availability for medical and scientific purposes. Despite the mandate that these obligations be enforced equally, the dominant paradigm enshrined in the drug conventions is an enforcement-heavy criminal justice response to controlled substances that prohibits and penalizes their misuse. Prioritizing restrictive control is to the detriment of ensuring adequate availability of and access to controlled medicines, thereby violating the rights of people who need them. This paper argues that the drug conventions’ prioritization of criminal justice measures—including efforts to prevent non-medical use of controlled substances—undermines access to medicines and infringes upon the right to health and the right to enjoy the benefits of scientific progress. While the effects of criminalization under drug policy limit the right to health in multiple ways, we draw on research and documented examples to highlight the impact of drug control and criminalization on access to medicines. The prioritization and protection of human rights—specifically the right to health and the right to enjoy the benefits of scientific progress—are critical to rebalancing drug policy. PMID:28630556

  18. Complex systems relationships between control, communications and computing

    CERN Document Server

    2016-01-01

    This book gives a wide-ranging description of the many facets of complex dynamic networks and systems within an infrastructure provided by integrated control and supervision: envisioning, design, experimental exploration, and implementation. The theoretical contributions and the case studies presented can reach control goals beyond those of stabilization and output regulation or even of adaptive control. Reporting on work of the Control of Complex Systems (COSY) research program, Complex Systems follows from and expands upon an earlier collection: Control of Complex Systems by introducing novel theoretical techniques for hard-to-control networks and systems. The major common feature of all the superficially diverse contributions encompassed by this book is that of spotting and exploiting possible areas of mutual reinforcement between control, computing and communications. These help readers to achieve not only robust stable plant system operation but also properties such as collective adaptivity, integrity an...

  19. Short Distance Low Power Wireless Communication Access System%短距离低功率无线通信接入系统

    Institute of Scientific and Technical Information of China (English)

    谈振辉; 乔晓瑜

    2009-01-01

    Short distance low power wireless communication access technologies mainly concentrate in the physical layer and media access control (MAC) layer, including Bluetooth, Ultra-Wideband (UWB), Wi-Fi, etc. Bluetooth is a supplementary technology for short distance data transmission between devices; UWB is a type of narrow band pulse wireless technology for the connection with a variety of devices, providing fair flexibility and mobility; Wi-Fi is used to provide wireless connection for both instant access equipment and WLAN mobile devices, applied in long distance connection and to support the access for a certain power mobile terminals. Although the standardization progress of short distance low power wireless communication access systems is very fast and there are many supplementary standards, the most dominant ones are still Bluetooth and Wi-Fi.%短距离低功率无线通信接入技术主要集中在物理层和媒体访问控制(MAC)层,包括蓝牙、超宽带(UWB)和Wi-Fi等.蓝牙是链接近距离设备的电缆数据传送的辅助技术;UWB作为窄脉冲无线电技术链接众多电子设备,提供宽带无线接入的灵活性和移动性;Wi-Fi给快速接入设备和WLAN内移动设备提供无线链接,用于较长距离链接,支持一定功率的移动终端接入.短距离低功率无线通信接入系统的标准化进程非常快,辅助标准多,但目前仍以蓝牙和Wi-Fi为主.

  20. A TDMA based media access control protocol for wireless ad hoc networks

    Science.gov (United States)

    Yang, Qi; Tang, Biyu

    2013-03-01

    This paper presents a novel Time Division Multiplex Access (TDMA) based Media Access Control (MAC) protocol of wireless Ad Hoc network. To achieve collision free transmission, time slots in a MAC frame are cataloged into three types, that is access slot, control slot and traffic slot. Nodes in the network access to the network in the access slot, and an exclusive control is allocated subsequently. Data packets are transmission by dynamic schedule the traffic slots. Throughput and transmission delay are also analyzed by simulation experiment. The proposed protocol is capable of providing collision free transmission and achieves high throughput.

  1. Principles of Eliminating Access Control Lists within a Domain

    Directory of Open Access Journals (Sweden)

    Vic Grout

    2012-04-01

    Full Text Available The infrastructure of large networks is broken down into areas that have a common security policy called a domain. Security within a domain is commonly implemented at all nodes. However this can have a negative effect on performance since it introduces a delay associated with packet filtering. When Access Control Lists (ACLs are used within a router for this purpose then a significant overhead is introduced associated with this process. It is likely that identical checks are made at multiple points within a domain prior to a packet reaching its destination. Therefore by eliminating ACLs within a domain by modifying the ingress/egress points with equivalent functionality an improvement in the overall performance can be obtained. This paper considers the effect of the delays when using router operating systems offering different levels of functionality. It considers factors which contribute to the delay particularly due to ACLs and by using theoretical principles modified by practical calculation a model is created. Additionally this paper provides an example of an optimized solution which reduces the delay through network routers by distributing the security rules to the ingress/egress points of the domain without affecting the security policy.

  2. Bilateral Control Using Master/Slave Simulator for Haptic Communication

    Science.gov (United States)

    Yokokura, Yuki; Katsura, Seiichiro; Ohishi, Kiyoshi

    A bilateral controller is used to transmit and share haptic information between a master system and a slave system. In a transmission system, the bilateral controller encounters problems in the event of data packet loss and/or disconnections. In this study, a master/slave simulator and environmental data memory are used to solve the problems. In the case of normal operation, the environmental data memory stores force data in a remote side. The control system is operated by the environmental data memory and master/slave simulator when the communication lines are disconnected.

  3. An Efficient Role and Object Based Access Control Model Implemented in a PDM System

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiaowen; TAN Jian; HUANG Xiangguo

    2006-01-01

    An effective and reliable access control is crucial to a PDM system. This article has discussed the commonly used access control models, analyzed their advantages and disadvantages, and proposed a new Role and Object based access control model that suits the particular needs of a PDM system. The new model has been implemented in a commercial PDM system, which has demonstrated enhanced flexibility and convenience.

  4. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    OpenAIRE

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an active mobile device to enforce centralized ACL-based access control policies. Selective RFID Jamming also solves a Differential Signal Analysis attack to which the RFID Blocker Tag is susceptible.

  5. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    OpenAIRE

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an active mobile device to enforce centralized ACL-based access control policies. Selective RFID Jamming also solves a Differential Signal Analysis attack to which the RFID Blocker Tag is susceptible.

  6. Streetlight Control System Based on Wireless Communication over DALI Protocol

    Directory of Open Access Journals (Sweden)

    Francisco José Bellido-Outeiriño

    2016-04-01

    Full Text Available Public lighting represents a large part of the energy consumption of towns and cities. Efficient management of public lighting can entail significant energy savings. This work presents a smart system for managing public lighting networks based on wireless communication and the DALI protocol. Wireless communication entails significant economic savings, as there is no need to install new wiring and visual impacts and damage to the facades of historical buildings in city centers are avoided. The DALI protocol uses bidirectional communication with the ballast, which allows its status to be controlled and monitored at all times. The novelty of this work is that it tackles all aspects related to the management of public lighting: a standard protocol, DALI, was selected to control the ballast, a wireless node based on the IEEE 802.15.4 standard with a DALI interface was designed, a network layer that considers the topology of the lighting network has been developed, and lastly, some user-friendly applications for the control and maintenance of the system by the technical crews of the different towns and cities have been developed.

  7. Streetlight Control System Based on Wireless Communication over DALI Protocol.

    Science.gov (United States)

    Bellido-Outeiriño, Francisco José; Quiles-Latorre, Francisco Javier; Moreno-Moreno, Carlos Diego; Flores-Arias, José María; Moreno-García, Isabel; Ortiz-López, Manuel

    2016-04-27

    Public lighting represents a large part of the energy consumption of towns and cities. Efficient management of public lighting can entail significant energy savings. This work presents a smart system for managing public lighting networks based on wireless communication and the DALI protocol. Wireless communication entails significant economic savings, as there is no need to install new wiring and visual impacts and damage to the facades of historical buildings in city centers are avoided. The DALI protocol uses bidirectional communication with the ballast, which allows its status to be controlled and monitored at all times. The novelty of this work is that it tackles all aspects related to the management of public lighting: a standard protocol, DALI, was selected to control the ballast, a wireless node based on the IEEE 802.15.4 standard with a DALI interface was designed, a network layer that considers the topology of the lighting network has been developed, and lastly, some user-friendly applications for the control and maintenance of the system by the technical crews of the different towns and cities have been developed.

  8. 21 CFR 1311.125 - Requirements for establishing logical access control-Individual practitioner.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Requirements for establishing logical access... Prescriptions § 1311.125 Requirements for establishing logical access control—Individual practitioner. (a) At... his two-factor authentication credential to satisfy the logical access controls. The second...

  9. 21 CFR 1311.130 - Requirements for establishing logical access control-Institutional practitioner.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Requirements for establishing logical access...) Electronic Prescriptions § 1311.130 Requirements for establishing logical access control—Institutional... practitioner that enters permissions for logical access controls into the application. The...

  10. 78 FR 16757 - Twentieth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-03-18

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held April 4, 2013 from...

  11. 76 FR 59481 - Ninth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-09-26

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 224: Airport Security Access Control...

  12. 78 FR 43963 - Twenty-Third Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-07-22

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held on June 20,...

  13. 77 FR 71474 - Seventeenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-11-30

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held December 13,...

  14. 77 FR 15448 - Twelfth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-03-15

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of meeting RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... 224, Airport Security Access Control Systems DATES: The meeting will be held April 5, 2012, from 10...

  15. 78 FR 22025 - Twenty First Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-04-12

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held April 9-10,...

  16. 77 FR 55894 - Fifteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-09-11

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems DATES: The meeting will be held September 27-28,...

  17. 76 FR 38742 - Seventh Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-07-01

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held July 15, 2011, from 10 a.m. to 1 p.m....

  18. 77 FR 64838 - Sixteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-10-23

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held November 15,...

  19. 78 FR 7850 - Nineteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-02-04

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held February 21,...

  20. 76 FR 3931 - Fourth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-01-21

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 Meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held February 8, 2011, from 10 a.m. to 5...

  1. 75 FR 71790 - Second Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-11-24

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held December 9, 2010, from 10 a.m. to 5...

  2. 77 FR 2343 - Eleventh Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-01-17

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY: The FAA..., Airport Security Access Control Systems. DATES: The meeting will be held February 9, 2012, from 10...

  3. Enhanced Communication Network Solution for Positive Train Control Implementation

    Science.gov (United States)

    Fatehi, M. T.; Simon, J.; Chang, W.; Chow, E. T.; Burleigh, S. C.

    2011-01-01

    The commuter and freight railroad industry is required to implement Positive Train Control (PTC) by 2015 (2012 for Metrolink), a challenging network communications problem. This paper will discuss present technologies developed by the National Aeronautics and Space Administration (NASA) to overcome comparable communication challenges encountered in deep space mission operations. PTC will be based on a new cellular wireless packet Internet Protocol (IP) network. However, ensuring reliability in such a network is difficult due to the "dead zones" and transient disruptions we commonly experience when we lose calls in commercial cellular networks. These disruptions make it difficult to meet PTC s stringent reliability (99.999%) and safety requirements, deployment deadlines, and budget. This paper proposes innovative solutions based on space-proven technologies that would help meet these challenges: (1) Delay Tolerant Networking (DTN) technology, designed for use in resource-constrained, embedded systems and currently in use on the International Space Station, enables reliable communication over networks in which timely data acknowledgments might not be possible due to transient link outages. (2) Policy-Based Management (PBM) provides dynamic management capabilities, allowing vital data to be exchanged selectively (with priority) by utilizing alternative communication resources. The resulting network may help railroads implement PTC faster, cheaper, and more reliably.

  4. Enhanced Communication Network Solution for Positive Train Control Implementation

    Science.gov (United States)

    Fatehi, M. T.; Simon, J.; Chang, W.; Chow, E. T.; Burleigh, S. C.

    2011-01-01

    The commuter and freight railroad industry is required to implement Positive Train Control (PTC) by 2015 (2012 for Metrolink), a challenging network communications problem. This paper will discuss present technologies developed by the National Aeronautics and Space Administration (NASA) to overcome comparable communication challenges encountered in deep space mission operations. PTC will be based on a new cellular wireless packet Internet Protocol (IP) network. However, ensuring reliability in such a network is difficult due to the "dead zones" and transient disruptions we commonly experience when we lose calls in commercial cellular networks. These disruptions make it difficult to meet PTC s stringent reliability (99.999%) and safety requirements, deployment deadlines, and budget. This paper proposes innovative solutions based on space-proven technologies that would help meet these challenges: (1) Delay Tolerant Networking (DTN) technology, designed for use in resource-constrained, embedded systems and currently in use on the International Space Station, enables reliable communication over networks in which timely data acknowledgments might not be possible due to transient link outages. (2) Policy-Based Management (PBM) provides dynamic management capabilities, allowing vital data to be exchanged selectively (with priority) by utilizing alternative communication resources. The resulting network may help railroads implement PTC faster, cheaper, and more reliably.

  5. Communication Apprehension. Focused Access to Selected Topics (FAST) Bibliography No. 15.

    Science.gov (United States)

    Shermis, Michael

    This annotated bibliography contains 31 references of articles and papers in the ERIC database that deal with communication apprehension (CA). The first section provides strategies for instructors and students to alleviate communication apprehension, speech anxiety, stage fright, and other problems people have with public speaking. The second…

  6. Wi-Fi Networks Security and Accessing Control

    Directory of Open Access Journals (Sweden)

    Tarek S. Sobh

    2013-06-01

    Full Text Available As wireless networks access gains popularity in corporate, private and personal networks, the nature of wireless networks opens up new possibilities for network attacks. This paper negotiating Wi-Fi security against scanning of rogue Wi-Fi networks and other related activities and considers the monitoring of Wi-Fi traffic effects. The unauthorized access point (AP problem has raised more attention and resulted in obtaining wireless access without subscriber permission.This work assumes Wi-Fi AP under attack specially rogue AP and/or ad-hoc client. It provides a solution for detecting and preventing this attack. In addition, it provides the required user permissions to allow/block access of the files on the user of ad-hoc client. The experiments include the rogue AP attack are maintained and the effectiveness of the proposed solution are tested.

  7. Optical label-controlled transparent metro-access network interface

    DEFF Research Database (Denmark)

    Osadchiy, Alexey Vladimirovich

    This thesis presents results obtained during the course of my PhD research on optical signal routing and interfacing between the metropolitan and access segments of optical networks. Due to both increasing capacity demands and variety of emerging services types, new technological challenges...... are arising for seamlessly interfacing metropolitan and access networks. Therefore, in this PhD project, I have analyzed those technological challenges and identified the key aspects to be addressed. I have also proposed and experimentally verified a number of solutions to metropolitan and access networks...... interfacing and signal routing. Equipment and infrastructure simplification was recognized as the path towards more efficient metropolitan and access networks providing a spectrum of high-bandwidth services to large number of users. Several approaches have been proposed and developed in order to enable...

  8. Role-based access control through on-demand classification of electronic health record.

    Science.gov (United States)

    Tiwari, Basant; Kumar, Abhay

    2015-01-01

    Electronic health records (EHR) provides convenient method to exchange medical information of patients between different healthcare providers. Access control mechanism in healthcare services characterises authorising users to access EHR records. Role Based Access Control helps to restrict EHRs to users in a certain role. Significant works have been carried out for access control since last one decade but little emphasis has been given to on-demand role based access control. Presented work achieved access control through physical data isolation which is more robust and secure. We propose an algorithm in which selective combination of policies for each user of the EHR database has been defined. We extend well known data mining technique 'classification' to group EHRs with respect to the given role. Algorithm works by taking various roles as class and defined their features as a vector. Here, features are used as a Feature Vector for classification to describe user authority.

  9. Display For Command, Control, Communication and Intelligence System

    Directory of Open Access Journals (Sweden)

    S. Prabhu

    1998-04-01

    Full Text Available Display subsystem is an important part of command, control, communication and intelligence(C31 system. The display used in C31 system for air defence should provide a panoramic view of thecomplete air segment under its command and control in real-time. The necessary information requiredfor taking a quick decision should be available to the commander in easily understandable graphicformat This paper describes salient features of the display known as synthetic radar situation display(SRSD developed by the Defence Electronics Research Laboratory (DLRL, Hyderabad, for such applications

  10. NASA Unmanned Aircraft (UA) Control and Non-Payload Communication (CNPC) System Waveform Trade Studies

    Science.gov (United States)

    Chavez, Carlos; Hammel, Bruce; Hammel, Allan; Moore, John R.

    2014-01-01

    Unmanned Aircraft Systems (UAS) represent a new capability that will provide a variety of services in the government (public) and commercial (civil) aviation sectors. The growth of this potential industry has not yet been realized due to the lack of a common understanding of what is required to safely operate UAS in the National Airspace System (NAS). To address this deficiency, NASA has established a project called UAS Integration in the NAS (UAS in the NAS), under the Integrated Systems Research Program (ISRP) of the Aeronautics Research Mission Directorate (ARMD). This project provides an opportunity to transition concepts, technology, algorithms, and knowledge to the Federal Aviation Administration (FAA) and other stakeholders to help them define the requirements, regulations, and issues for routine UAS access to the NAS. The safe, routine, and efficient integration of UAS into the NAS requires new radio frequency (RF) spectrum allocations and a new data communications system which is both secure and scalable with increasing UAS traffic without adversely impacting the Air Traffic Control (ATC) communication system. These data communications, referred to as Control and Non-Payload Communications (CNPC), whose purpose is to exchange information between the unmanned aircraft and the ground control station to ensure safe, reliable, and effective unmanned aircraft flight operation. A Communications Subproject within the UAS in the NAS Project has been established to address issues related to CNPC development, certification and fielding. The focus of the Communications Subproject is on validating and allocating new RF spectrum and data link communications to enable civil UAS integration into the NAS. The goal is to validate secure, robust data links within the allocated frequency spectrum for UAS. A vision, architectural concepts, and seed requirements for the future commercial UAS CNPC system have been developed by RTCA Special Committee 203 (SC-203) in the process

  11. Nonverbal social communication and gesture control in schizophrenia.

    Science.gov (United States)

    Walther, Sebastian; Stegmayer, Katharina; Sulzbacher, Jeanne; Vanbellingen, Tim; Müri, René; Strik, Werner; Bohlhalter, Stephan

    2015-03-01

    Schizophrenia patients are severely impaired in nonverbal communication, including social perception and gesture production. However, the impact of nonverbal social perception on gestural behavior remains unknown, as is the contribution of negative symptoms, working memory, and abnormal motor behavior. Thus, the study tested whether poor nonverbal social perception was related to impaired gesture performance, gestural knowledge, or motor abnormalities. Forty-six patients with schizophrenia (80%), schizophreniform (15%), or schizoaffective disorder (5%) and 44 healthy controls matched for age, gender, and education were included. Participants completed 4 tasks on nonverbal communication including nonverbal social perception, gesture performance, gesture recognition, and tool use. In addition, they underwent comprehensive clinical and motor assessments. Patients presented impaired nonverbal communication in all tasks compared with controls. Furthermore, in contrast to controls, performance in patients was highly correlated between tasks, not explained by supramodal cognitive deficits such as working memory. Schizophrenia patients with impaired gesture performance also demonstrated poor nonverbal social perception, gestural knowledge, and tool use. Importantly, motor/frontal abnormalities negatively mediated the strong association between nonverbal social perception and gesture performance. The factors negative symptoms and antipsychotic dosage were unrelated to the nonverbal tasks. The study confirmed a generalized nonverbal communication deficit in schizophrenia. Specifically, the findings suggested that nonverbal social perception in schizophrenia has a relevant impact on gestural impairment beyond the negative influence of motor/frontal abnormalities. © The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  12. Scientific Communication in the Developing World in an Open Access Mode: The SciELO Model

    Institute of Scientific and Technical Information of China (English)

    Rogerio Meneghini; Abel L. Packer

    2006-01-01

    This paper introduces the Scientific Electronic Library Online (SciELO) program and its three main objectives. Then the paper presents the methodology of open access to scientific information by the SciELO. At last, it shows the perspectives of open access in developing countries.

  13. Efficient LTE Access with Collision Resolution for Massive M2M Communications

    DEFF Research Database (Denmark)

    Madueño, Germán Corrales; Stefanovic, Cedomir; Popovski, Petar

    2014-01-01

    LTE random access procedure performs satisfactorily in case of asynchronous, uncorrelated traffic arrivals. However, when the arrivals are correlated and arrive synchronously, the performance of the random access channel (RACH) is drastically reduced, causing a large number of devices to experien...

  14. Task-and-role-based access-control model for computational grid

    Institute of Scientific and Technical Information of China (English)

    LONG Tao; HONG Fan; WU Chi; SUN Ling-li

    2007-01-01

    Access control in a grid environment is a challenging issue because the heterogeneous nature and independent administration of geographically dispersed resources in grid require access control to use fine-grained policies. We established a task-and-role-based access-control model for computational grid (CG-TRBAC model), integrating the concepts of role-based access control (RBAC) and task-based access control (TBAC). In this model, condition restrictions are defined and concepts specifically tailored to Workflow Management System are simplified or omitted so that role assignment and security administration fit computational grid better than traditional models; permissions are mutable with the task status and system variables, and can be dynamically controlled. The CG-TRBAC model is proved flexible and extendible. It can implement different control policies. It embodies the security principle of least privilege and executes active dynamic authorization. A task attribute can be extended to satisfy different requirements in a real grid system.

  15. Communications and control for electric power systems: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kirkham, H.

    1998-04-01

    This report is a summary of some of the work done on the Communications and Control project, with particular emphasis on the achievements during the years 1986--1996. During those years, the project moved away from concern with dispersed storage and generation and its impact on power system operation (the team was responsible for studies in this area, and for making a power system simulator that included DSG), and became involved in more concrete work aimed at applying high-tech solutions to problems of power system communications and control. This report covers work done at JPL on the following topics: (1) the measurement of electric and magnetic fields, both ac and dc; (2) the use of optical power to supply low-power electronics; (3) the design of a fault-tolerant communication system designed for distribution automation; and (4) a digital phase locked loop that allows the use of low-power transmitting electronics to recreate a good-quality signal at the receiver. In a report of this kind, only the results and highlights of the work are described.

  16. Ground control to major TOM: mitochondria-nucleus communication.

    Science.gov (United States)

    Eisenberg-Bord, Michal; Schuldiner, Maya

    2017-01-01

    Mitochondria have crucial functions in the cell, including ATP generation, iron-sulfur cluster biogenesis, nucleotide biosynthesis, and amino acid metabolism. All of these functions require tight regulation on mitochondrial activity and homeostasis. As mitochondria biogenesis is controlled by the nucleus and almost all mitochondrial proteins are encoded by nuclear genes, a tight communication network between mitochondria and the nucleus has evolved, which includes signaling cascades, proteins which are dual-localized to the two compartments, and sensing of mitochondrial products by nuclear proteins. All of these enable a crosstalk between mitochondria and the nucleus that allows the 'ground control' to get information on mitochondria's status. Such information facilitates the creation of a cellular balance of mitochondrial status with energetic needs. This communication also allows a transcriptional response in case mitochondrial function is impaired aimed to restore mitochondrial homeostasis. As mitochondrial dysfunction is related to a growing number of genetic diseases as well as neurodegenerative conditions and aging, elucidating the mechanisms governing the mitochondrial/nuclear communication should progress a better understanding of mitochondrial dysfunctions. © 2016 Federation of European Biochemical Societies.

  17. Enhancing risk communication for more effective epidemic control in Taiwan.

    Science.gov (United States)

    Ou, Shih-Ming; Liu, Li-Ling; Chin, Ko-Chien

    2014-01-01

    This article investigates how to more effectively conduct risk communication to increase the probability of successful control of an epidemic in Taiwan. The epidemic control of H1N1 in Taiwan in 2010 was studied. We used factor analysis and Decision-Making Trial and Evaluation Laboratory (DEMATEL) to obtain the total influence for each factor and to determine the critical factors among them. After being processed using proposed operational procedures, we obtained the critical factors and found that the government plays the key role in successful epidemic control. To reduce the resistance to efforts that seek to prevent pandemic crises, some necessary intervention activities, such as fairly and honorably exploring the complete relevant information and revealing the side effects of vaccines in a manner that is easily understood, were recommended. These could lead to an increase in immunizations among Taiwanese people by gaining their trust and commitment, thus achieving control of this epidemic.

  18. THE COMMUNICATION OF INTERNAL CONTROL SYSTEM WEAKNESSES - NECESSITY AND RESPONSIBILITY

    Directory of Open Access Journals (Sweden)

    Mariana, NEDELCU (BUNEA

    2014-11-01

    Full Text Available In terms of its mission, the control is an inherent part of management, being a specifically human activity, especially useful serving both the management, business partners, public institutions and public. Especially in the last period, amid the economic and financial crisis manifested in recent years, the control has evolved and evolving both by the improvement of organization and management systems and by the response to continuous development of the environment in which it operates. The control activities are an integral part of the management process by which the entity aims to achieve their objectives. The research methodology consists essentially in a literature review and recent regulations in the analyzed field.The objective of this study is to highlight the way in which shall be communicated the deficiencies of internal control systems, to the persons responsible for their governance, inclusively in the banking system.

  19. Reputation, relationships, risk communication, and the role of trust in the prevention and control of communicable disease: a review.

    Science.gov (United States)

    Cairns, Georgina; de Andrade, Marisa; MacDonald, Laura

    2013-01-01

    Population-level compliance with health protective behavioral advice to prevent and control communicable disease is essential to optimal effectiveness. Multiple factors affect perceptions of trustworthiness, and trust in advice providers is a significant predeterminant of compliance. While competency in assessment and management of communicable disease risks is critical, communications competency may be equally important. Organizational reputation, quality of stakeholder relationships and risk information provision strategies are trust moderating factors, whose impact is strongly influenced by the content, timing and coordination of communications. This article synthesizes the findings of 2 literature reviews on trust moderating communications and communicable disease prevention and control. We find a substantial evidence base on risk communication, but limited research on other trust building communications. We note that awareness of good practice historically has been limited although interest and the availability of supporting resources is growing. Good practice and policy elements are identified: recognition that crisis and risk communications require different strategies; preemptive dialogue and planning; evidence-based approaches to media relations and messaging; and building credibility for information sources. Priority areas for future research include process and cost-effectiveness evaluation and the development of frameworks that integrate communication and biomedical disease control and prevention functions, conceptually and at scale.

  20. Implementing Discretionary Access Control with Time Character in Linux and Performance Analysis

    Institute of Scientific and Technical Information of China (English)

    TAN Liang; ZHOU Ming-Tian

    2006-01-01

    DAC (Discretionary Access Control Policy) is access control based on ownership relations between subject and object, the subject can discretionarily decide on that who, by what methods, can access his owns object. In this paper, the system time is looked as a basic secure element. The DAC_T (Discretionary Access Control Policy with Time Character) is presented and formalized. The DAC_T resolves that the subject can discretionarily decide that who, on when, can access his owns objects. And then the DAC_T is implemented on Linux based on GFAC (General Framework for Access Control), and the algorithm is put forward. Finally, the performance analysis for the DAC_T_Linux is carried out. It is proved that the DAC_T_Linux not only can realize time constraints between subject and object but also can still be accepted by us though its performance have been decreased.

  1. An effective access control approach to support mobility in IPv6 networks

    Science.gov (United States)

    Peng, Xue-hai; Lin, Chuang

    2005-11-01

    Access control is an important method to improve network security and prevent protected resources from being used by some nodes without authority. Moreover, mobility is an important trend of internet. In this paper, based on the architecture of hierarchical mobile IPv6, we proposed an effective access control approach to support mobility in IPv6 networks, which can ensure the operation of access control when a mobile node roams in these domains with different polices, with decreased delay of access negotiation and cost of delivering messages.

  2. A New Key-lock Method for User Authentication and Access Control

    Institute of Scientific and Technical Information of China (English)

    JI Dongyao; ZHANG Futai; WANG Yumin

    2001-01-01

    We propose a new key-lock methodfor user authentication and access control based onChinese remainder theorem, the concepts of the ac-cess control matrix, key-lock-pair, time stamp, and the NS public key protocol. Our method is dynamicand needs a minimum amount of computation in thesense that it only updates at most one key/lock foreach access request. We also demonstrate how an au-thentication protocol can be integrated into the ac-cess control method. By applying a time stamp, themethod can not only withstand replay attack, butalso strengthen the authenticating mechanism, whichcould not be achieved simultaneously in previous key-lock methods.

  3. Containment control of multi-agent systems with unbounded communication delays

    Science.gov (United States)

    Shen, Jun; Lam, James

    2016-07-01

    In this paper, we address the containment control problem for multi-agent systems under heterogeneous unbounded communication delays with emphasis on the convergence rate analysis. Different from most works on multi-agent systems, we resort to a viewpoint from the area of positive delay systems. We first cast the containment control problem into the stability analysis of an associated error system. In order to capture the convergence rate, we introduce a nondecreasing positive function whose reciprocal represents the decay rate of the associated error system. Under the assumption that each follower has access to at least one leader and some mild hypotheses on the communication delays, an explicit condition is given to characterise the decay rate of the associated error system in terms of linear programming. In addition, we provide several special cases when the communication delays are restricted by linear, sublinear and logarithmic growth rates, respectively. Finally, through numerical examples, it is shown that the convergence rate is dominated by the delays being the highest order infinitely large quantity.

  4. Communication

    NARCIS (Netherlands)

    Sigafoos, J.; Lancioni, G.E.; O'Reilly, M.F.; Lang, R.; Singh, N.N.; Didden, H.C.M.; Green, V.A.; Marschik, P.B.

    2016-01-01

    Communication disorders are common among people with intellectual disabilities. Consequently, enhancing the communication skills of such individuals is a major intervention priority. This chapter reviews the nature and prevalence of the speech, language, and communication problems associated with

  5. Open access, readership, citations: a randomized controlled trial of scientific journal publishing.

    Science.gov (United States)

    Davis, Philip M

    2011-07-01

    Does free access to journal articles result in greater diffusion of scientific knowledge? Using a randomized controlled trial of open access publishing, involving 36 participating journals in the sciences, social sciences, and humanities, we report on the effects of free access on article downloads and citations. Articles placed in the open access condition (n=712) received significantly more downloads and reached a broader audience within the first year, yet were cited no more frequently, nor earlier, than subscription-access control articles (n=2533) within 3 yr. These results may be explained by social stratification, a process that concentrates scientific authors at a small number of elite research universities with excellent access to the scientific literature. The real beneficiaries of open access publishing may not be the research community but communities of practice that consume, but rarely contribute to, the corpus of literature.

  6. H-RBAC: A Hierarchical Access Control Model for SaaS Systems

    Directory of Open Access Journals (Sweden)

    Dancheng Li

    2011-08-01

    Full Text Available SaaS is a new way to deploy software as a hosted service and accessed over the Internet which means the customers don’t need to maintain the software code and data on their own servers. So it’s more important for SaaS systems to take security issues into account. Access control is a security mechanism that enables an authority to access to certain restricted areas and resources according to the permissions assigned to a user. Several access models have been proposed to realize the access control of single instance systems. However, most of the existing models couldn’t address the following SaaS system problems: (1 role name conflicts (2 cross-level management (3 the isomerism of tenants' access control (4 temporal delegation constraints. This paper describes a hierarchical RBAC model called H-RBAC solves all the four problems of SaaS systems mentioned above. This model addresses the SaaS system access control in both system level and tenant level. It combines the advantages of RBDM and ARBAC97 model and introduces temporal constraints to SaaS access control model. In addition, a practical approach to implement the access control module for SaaS systems based on H-RBAC model is also proposed in this paper.

  7. Access control and privilege management in electronic health record: a systematic literature review.

    Science.gov (United States)

    Jayabalan, Manoj; O'Daniel, Thomas

    2016-12-01

    This study presents a systematic literature review of access control for electronic health record systems to protect patient's privacy. Articles from 2006 to 2016 were extracted from the ACM Digital Library, IEEE Xplore Digital Library, Science Direct, MEDLINE, and MetaPress using broad eligibility criteria, and chosen for inclusion based on analysis of ISO22600. Cryptographic standards and methods were left outside the scope of this review. Three broad classes of models are being actively investigated and developed: access control for electronic health records, access control for interoperability, and access control for risk analysis. Traditional role-based access control models are extended with spatial, temporal, probabilistic, dynamic, and semantic aspects to capture contextual information and provide granular access control. Maintenance of audit trails and facilities for overriding normal roles to allow full access in emergency cases are common features. Access privilege frameworks utilizing ontology-based knowledge representation for defining the rules have attracted considerable interest, due to the higher level of abstraction that makes it possible to model domain knowledge and validate access requests efficiently.

  8. 75 FR 47464 - Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control...

    Science.gov (United States)

    2010-08-06

    ... circumvention of copyright protection systems for access control technologies which was published July 27, 2010... Copyright Office 37 CFR Part 201 Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control Technologies AGENCY: Copyright Office, Library of Congress. ACTION: Final...

  9. 75 FR 61819 - First Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-10-06

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): November 2, 2010 Welcome/Introductions/Administrative Remarks Agenda... Federal Aviation Administration First Meeting: RTCA Special Committee 224: Airport Security Access...

  10. 76 FR 16470 - Sixth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-03-23

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): Agenda April 13, 2011 Welcome/Introductions/Administrative Remarks... Federal Aviation Administration Sixth Meeting: RTCA Special Committee 224: Airport Security Access...

  11. 75 FR 80886 - Third Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-12-23

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): Agenda January 13, 2011 Welcome/Introductions/Administrative Remarks... Federal Aviation Administration Third Meeting: RTCA Special Committee 224: Airport Security Access...

  12. Owner-Based Role-Based Access Control OB-RBAC

    NARCIS (Netherlands)

    Saffarian, Mohsen; Sadighi, Babak

    2010-01-01

    Administration of an access control model deals with the question of who is authorized to update policies defined on the basis of that model. One of the models whose administration has absorbed relatively large research is the Role-Based Access Control (RBAC) model. All the existing role-based admin

  13. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    NARCIS (Netherlands)

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an a

  14. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    NARCIS (Netherlands)

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an a

  15. A novel decentralized hierarchical access control scheme for the medical scenario

    DEFF Research Database (Denmark)

    Eskeland, Sigurd; Prasad, Neeli R.

    2006-01-01

    to be the property of the corresponding patient, it is justified that patients should have the opportunity to exert control over their own data. In this paper, we propose a cryptographic access control scheme allowing patients to grant medical teams authorizations to access their medical data. Moreover...

  16. Enhancing Security and Privacy in Video Surveillance through Role-Oriented Access Control Mechanism

    DEFF Research Database (Denmark)

    Mahmood Rajpoot, Qasim

    the explicitly stated ones due to the hierarchical relations between the attributes of different entities. We implement a prototype of the proposed mechanism and demonstrate that the access control policies using our approach may be specified via eXtensible Access Control Markup Language (XACML)....

  17. Modelling and Analysing Access Control Policies in XACML 3.0

    DEFF Research Database (Denmark)

    Ramli, Carroline Dewi Puspa Kencana

    XACML (eXtensible Access Control Markup Language) is a prominent access control language that is widely adopted both in industry and academia. XACML is an international standard in the field of information security. The problem with XACML is that its specification is described in natural language...

  18. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    NARCIS (Netherlands)

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an

  19. [Principles and stakes of external communication of healthcare networks: the case of heathcare networks for health services accessibility].

    Science.gov (United States)

    Plu, Isabelle; Gignon, Maxime; Emery, Sophie; Purssell-François, Irène; Moutel, Grégoire; Hervé, Christian

    2009-01-01

    Healthcare networks which purpose is to manage patients through better coordination of the care, need to develop a communication strategy to be recognized by the public and by healthcare professionals and to be inserted in the healthcare landscape. We firstly will present legal requirements related to external communication of healthcare networks. Then, we will describe the different tools which can be used to communicate about healthcare networks in its area, with the example from a healthcare network for health services accessibility. In the French Public health code, the legal status and the ethical charter of the healthcare network have to be delivered to the healthcare professionals in its area and to the patients. Moreover, the example healthcare network informed collectively and individually the healthcare professionals of its area about its activities. It made it known to the public by the way of departmental prevention manifestations and health education sessions in community social associations. From these examples, we will conduct an ethical reflection on the modalities and stakes of the external communication of healthcare networks.

  20. Communicable disease control in England; recommendations from an American.

    Science.gov (United States)

    Detels, R

    1994-12-01

    The problems associated with the Wakefield salmonella and the Stafford Legionnaires' disease outbreaks and the recommendations of the Acheson Committee formed in response led to the creation of the position of Consultant in Communicable Disease Control (CCDC) within the District Health Authorities. The reality of the position as implemented differs from that envisaged by the Acheson Committee and has resulted in ambiguities about the role of the CsCDC, the source of their support, and the range of their responsibilities. This paper, by an American invited to review the position, outlines the history of the position, the current status of CsCDC, and the barriers to effective performance of the position. It ends with a series of recommendations for improving disease control within England by solidifying the position, establishing its role in disease control within the National Health Service and recommending an educational/training pathway to attract and prepare physicians for the position.

  1. VCSEL-based gigabit IR-UWB link for converged communication and sensing applications in optical metro-access networks

    DEFF Research Database (Denmark)

    Pham, Tien Thang; Gibbon, Timothy Braidwood; Tafur Monroy, Idelfonso

    2012-01-01

    We report on experimental demonstration of an impulse radio ultrawideband (IR-UWB) based converged communication and sensing system. A 1550-nm VCSEL-generated IR-UWB signal is used for 2-Gbps wireless data distribution over 800-m and 50-km single mode fiber links which present short-range in......-building and long-reach access network applications. The IR-UWB signal is also used to simultaneously measure the rotational speed of a blade spinning between 18 and 30 Hz. To the best of our knowledge, this is the very first demonstration of a simultaneous gigabit UWB telecommunication and wireless UWB sensing...... application, paving the way forward for the development and deployment of converged UWB VCSEL-based technologies in access and in-building networks of the future....

  2. Access to the ophthalmic artery by retrograde approach through the posterior communicating artery for intra-arterial chemotherapy of retinoblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Chi-Tuan; Blanc, Raphael; Pistocchi, Silvia; Bartolini, Bruno; Piotin, Michel [Fondation Rothschild Hospital, Department of Interventional Neuroradiology, Paris (France); Lumbroso-Le Rouic, Livia [Institut Curie, Department of Ocular Oncology, Paris (France)

    2012-08-15

    Intra-arterial infusion of chemotherapy into the ophthalmic artery for treatment of retinoblastoma has been realized after catheterization of the internal carotid and temporary balloon occlusion beyond the orifice of the ophthalmic artery, or more recently after superselective canulation of the ophthalmic artery by a microcatheter. The superselective catheterization of the ophthalmic artery could be cumbersome because of the implantation of the ostium on the carotid siphon or because of the tortuosity of the carotid siphon. We report our experience of using a retrograde approach through the posterior communicating artery that allows a more direct angle of access to the origin of the ophthalmic artery. (orig.)

  3. Unequal error control scheme for dimmable visible light communication systems

    Science.gov (United States)

    Deng, Keyan; Yuan, Lei; Wan, Yi; Li, Huaan

    2017-01-01

    Visible light communication (VLC), which has the advantages of a very large bandwidth, high security, and freedom from license-related restrictions and electromagnetic-interference, has attracted much interest. Because a VLC system simultaneously performs illumination and communication functions, dimming control, efficiency, and reliable transmission are significant and challenging issues of such systems. In this paper, we propose a novel unequal error control (UEC) scheme in which expanding window fountain (EWF) codes in an on-off keying (OOK)-based VLC system are used to support different dimming target values. To evaluate the performance of the scheme for various dimming target values, we apply it to H.264 scalable video coding bitstreams in a VLC system. The results of the simulations that are performed using additive white Gaussian noises (AWGNs) with different signal-to-noise ratios (SNRs) are used to compare the performance of the proposed scheme for various dimming target values. It is found that the proposed UEC scheme enables earlier base layer recovery compared to the use of the equal error control (EEC) scheme for different dimming target values and therefore afford robust transmission for scalable video multicast over optical wireless channels. This is because of the unequal error protection (UEP) and unequal recovery time (URT) of the EWF code in the proposed scheme.

  4. A dynamic access control method based on QoS requirement

    Science.gov (United States)

    Li, Chunquan; Wang, Yanwei; Yang, Baoye; Hu, Chunyang

    2013-03-01

    A dynamic access control method is put forward to ensure the security of the sharing service in Cloud Manufacturing, according to the application characteristics of cloud manufacturing collaborative task. The role-based access control (RBAC) model is extended according to the characteristics of cloud manufacturing in this method. The constraints are considered, which are from QoS requirement of the task context to access control, based on the traditional static authorization. The fuzzy policy rules are established about the weighted interval value of permissions. The access control authorities of executable service by users are dynamically adjusted through the fuzzy reasoning based on the QoS requirement of task. The main elements of the model are described. The fuzzy reasoning algorithm of weighted interval value based QoS requirement is studied. An effective method is provided to resolve the access control of cloud manufacturing.

  5. The Study of Access Control for Service-Oriented Computing in Internet of Things

    Directory of Open Access Journals (Sweden)

    Guoping Zhang

    2012-06-01

    Full Text Available In Internet of Things, computing and processing of information is the core supporting. In this paper, we introduce “Service-Oriented Computing” to solve the computing and processing of information in IoT. However, a key challenge in service-oriented environment is the design of effective access control schemas.We put forward a model of Workflow -oriented Attributed Based Access Control (WABAC, and an access control framework based on WABAC model. WABAC model grants and adapts permissions to subjects according to subject atttribute, resource attribute, environment attribute and current task, meeting access control request of SOC. Using the approach presented can effectively enhance the access control security for SOC applications, and prevent the abuse of subject permissions.

  6. Performance analysis and overload control of an open service access (OSA) architecture

    Science.gov (United States)

    Andersson, Jens K.; Nyberg, Christian; Kihl, Maria

    2003-08-01

    The trend of the service architectures developed in telecommunications today is that they should be open in the sense that they can communicate over the borders of different networks. Instead of each network having their own service architecture with their own applications, all networks should be able to use the same applications. 3GPP, the organization developing specifications for the 3G networks has specified the standard Open Service Access (OSA), as a part of the 3G specification. OSA offers different Application Protocol Interfaces that enable an application that resides outside a network to use the capabilities of the network. This paper analyses the performance of an OSA gateway. It is examined how the overload control can be dealt with in a way to best satisfy the operators and the 3'rd parties. There are some guiding principles in the specifications, but a lot of decisions have to be made by the implementors of application servers and OSA gateways. Proposals of different requirements for an OSA architecture exist such as, minimum amount of accepted calls per second and time constraint for the maximal total delay for an application. Maximal and fair throughput have to be prioritized from the 3'rd parties view, but profit is the main interest from the operators point of view. Therefore this paper examines a priority based proposal of an overload control mechanism taking these aspects and requirements into account.

  7. Reliable Radio Access for Massive Machine-to-Machine (M2M) Communication

    DEFF Research Database (Denmark)

    Madueño, Germán Corrales

    Machine-to-Machine (M2M) communication is a term that identifies the emerging paradigm of interconnected systems, machines, and things that communicate and collaborate without human intervention. The characteristics of M2M Communications are small payloads and sporadic transmissions, while...... the service requirements can range from massive number of devices to ultra-reliable. This PhD thesis focuses on novel mechanisms to meet these requirements in a variety of wireless systems, from well-established technologies such as cellular networks, to emerging technologies like IEEE 802.11ah. Today...... an overwhelming 89% of the deployed M2M modules are GPRS-based. This motivates us to investigate the potential of GPRS as a dedicated M2M network. We show that by introducing minimal modifications to GPRS operation, a large number of devices can be reliably supported. Surprisingly, even though LTE is seen...

  8. HIERARCHICAL ACCESS CONTROL IN DYNAMIC PEER GROUPS USING SYMMETRIC POLYNOMIAL AND TREE BASED GROUP ELLIPTIC CURVE DIFFIE HELLMAN SCHEME

    Directory of Open Access Journals (Sweden)

    Nafeesa Begum Jeddy

    2014-01-01

    Full Text Available Hierarchical Access Control in group communication is an active area of research which is difficult to achieve it. Its primary objective is to allow users of a higher authority group to access information or resource held by lower group users and preventing the lower group users to access information held by higher class users. Large collection of collaborative applications in organizations inherently has hierarchical structures for functioning, where providing security by efficient group key management is a big challenging issue. While preserving centralized methods for hierarchical access control, it is difficult to achieve efficiency as a single membership change will result in lot of changes which are difficult to maintain. So, using distributed key agreement techniques is more appropriate for this scenario. This study explore on novel group key agreement approach, which combines both the symmetric polynomial scheme and Tree Based Group elliptic Curve key exchange. Also, it yields a secure protocol suite that is good in fault-tolerant and simple. The efficiency of SP-TGECDH is better than many other schemes. Using TGECDH makes the scheme suitable small Low powered devices.

  9. Secure Remote Access Issues in a Control Center Environment

    Science.gov (United States)

    Pitts, Lee; McNair, Ann R. (Technical Monitor)

    2002-01-01

    The ISS finally reached an operational state and exists for local and remote users. Onboard payload systems are managed by the Huntsville Operations Support Center (HOSC). Users access HOSC systems by internet protocols in support of daily operations, preflight simulation, and test. In support of this diverse user community, a modem security architecture has been implemented. The architecture has evolved over time from an isolated but open system to a system which supports local and remote access to the ISS over broad geographic regions. This has been accomplished through the use of an evolved security strategy, PKI, and custom design. Through this paper, descriptions of the migration process and the lessons learned are presented. This will include product decision criteria, rationale, and the use of commodity products in the end architecture. This paper will also stress the need for interoperability of various products and the effects of seemingly insignificant details.

  10. A Novel Architecture for Adaptive Traffic Control in Network on Chip using Code Division Multiple Access Technique

    Directory of Open Access Journals (Sweden)

    Fatemeh. Dehghani

    2016-08-01

    Full Text Available Network on chip has emerged as a long-term and effective method in Multiprocessor System-on-Chip communications in order to overcome the bottleneck in bus based communication architectures. Efficiency and performance of network on chip is so dependent on the architecture and structure of the network. In this paper a new structure and architecture for adaptive traffic control in network on chip using Code Division Multiple Access technique is presented. To solve the problem of synchronous access to bus based interconnection the code division multiple access technique was applied. In the presented structure that is based upon mesh topology and simple routing method we attempted to increase the exchanged data bandwidth rate among different cores. Also an attempt has been made to increase the performance by isolating the target address transfer path from data transfer path. The main goal of this paper is presenting a new structure to improve energy consumption, area and maximum frequency in network on chip systems using information coding and decoding techniques. The presented structure is simulated using Xilinx ISE software and the results show effectiveness of this architecture.

  11. Controls Over the Contractor Common Access Card Life Cycle

    Science.gov (United States)

    2008-10-10

    Identification System SES Senior Executive Service SPOC Service Point of Contact TASM Trusted Agent Security Manager USD (AT&L) Under...the final report by October 31, 2008. 53 Finding D. Oversight of Common Access Card Sponsors DoD CVS Service Points of Contact ( SPOCs ...authorization to approve contractor CACs. Organization of CAC Application Sites Each Service agency has an SPOC who is responsible for coordinating with

  12. Evolutionary Games for Multiple Access Control: From Egoism to Altruism

    OpenAIRE

    Gaiech, Houssem; El-Azouzi, Rachid; Haddad, Majed; Altman, Eitan; Mabrouki, Issam

    2014-01-01

    International audience; This paper studies multiple access games within a large population of mobiles decomposed into several groups. Mobiles interfere with each other through many local interactions. We assume that each mobile (or player) cooperates with its group by taking into account the performance of its group. We parameterize the degree of cooperation which allows to cover the fully non-cooperative behavior, the fully cooperative behavior, and even more, the fully altruistic behavior, ...

  13. Open access and the future of scholarly communication policy and infrastructure

    CERN Document Server

    Dickson, Katherine A

    2016-01-01

    It is impossible to imagine the future of academic libraries without an extensive consideration of open access the removal of price and permission barriers from scholarly research online. As textbook and journal subscription prices continue to rise, improvements in technology make online dissemination of scholarship less expensive, and faculty recognize the practical and philosophical appeal of making their work available to wider audiences. As a consequences, libraries have begun to consider a wide variety of open access flavors and business models. These new possibilities have significant impact on both library services and collection policies, and the call for new skills within library staffing. Volume 9 of the series Creating the 21st-Century Academic Library is the first of two addressing the topic of open access in academic libraries and focuses on policy and infrastructure for libraries that wish to provide leadership on their campus in the transition to more open forms of scholarship. Chapters in the ...

  14. The Crisis in Scholarly Communication, Open Access, and Open Data Policies: The Libraries' Perspective

    Science.gov (United States)

    Besara, Rachel

    2015-03-01

    For years the cost of STEM databases have exceeded the rate of inflation. Libraries have reallocated funds for years to continue to provide support to their scientific communities, but they are reaching a point at many institutions where they are no longer able to provide access to many databases considered standard to support research. A possible or partial alleviation to this problem is the federal open access mandate. However, this shift challenges the current model of publishing and data management in the sciences. This talk will discuss these topics from the perspective of research libraries supporting physics and the STEM disciplines.

  15. Characterization of accessibility for affine connection control systems at some points with nonzero velocity

    CERN Document Server

    Barbero-Liñán, María

    2011-01-01

    Affine connection control systems are mechanical control systems that model a wide range of real systems such as robotic legs, hovercrafts, planar rigid bodies, rolling pennies, snakeboards and so on. In 1997 the accessibility and a particular notion of controllability was intrinsically described by A. D. Lewis and R. Murray at points of zero velocity. Here, we present a novel generalization of the description of accessibility algebra for those systems at some points with nonzero velocity as long as the affine connection restricts to the distribution given by the symmetric closure. The results are used to describe the accessibility algebra of different mechanical control systems.

  16. Requirements and Challenges of Location-Based Access Control in Healthcare Emergency Response

    DEFF Research Database (Denmark)

    Vicente, Carmen Ruiz; Kirkpatrick, Michael; Ghinita, Gabriel

    2009-01-01

    Recent advances in positioning and tracking technologies have led to the emergence of novel location-based applications that allow participants to access information relevant to their spatio-temporal context. Traditional access control models, such as role-based access control (RBAC), are not suf......Recent advances in positioning and tracking technologies have led to the emergence of novel location-based applications that allow participants to access information relevant to their spatio-temporal context. Traditional access control models, such as role-based access control (RBAC......), are not sufficient to address the new challenges introduced by these location-based applications. Several recent research efforts have enhanced RBAC with spatio-temporal features. Nevertheless, the state-of-the-art does not deal with mobility of both subjects and objects and does not support the utilization...... of complex access control decisions based on spatio-temporal relationships among subjects and objects. Furthermore, such relationships change frequently in dynamic environments, requiring efficient mechanisms to monitor and re-evaluate access control decisions. In this position paper, we present a healthcare...

  17. A General Attribute and Rule Based Role-Based Access Control Model

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Growing numbers of users and many access control policies which involve many different resource attributes in service-oriented environments bring various problems in protecting resource. This paper analyzes the relationships of resource attributes to user attributes in all policies, and propose a general attribute and rule based role-based access control(GAR-RBAC) model to meet the security needs. The model can dynamically assign users to roles via rules to meet the need of growing numbers of users. These rules use different attribute expression and permission as a part of authorization constraints, and are defined by analyzing relations of resource attributes to user attributes in many access policies that are defined by the enterprise. The model is a general access control model, and can support many access control policies, and also can be used to wider application for service. The paper also describes how to use the GAR-RBAC model in Web service environments.

  18. A Fault-Tolerant Emergency-Aware Access Control Scheme for Cyber-Physical Systems

    CERN Document Server

    Wu, Guowei; Xia, Feng; Yao, Lin

    2012-01-01

    Access control is an issue of paramount importance in cyber-physical systems (CPS). In this paper, an access control scheme, namely FEAC, is presented for CPS. FEAC can not only provide the ability to control access to data in normal situations, but also adaptively assign emergency-role and permissions to specific subjects and inform subjects without explicit access requests to handle emergency situations in a proactive manner. In FEAC, emergency-group and emergency-dependency are introduced. Emergencies are processed in sequence within the group and in parallel among groups. A priority and dependency model called PD-AGM is used to select optimal response-action execution path aiming to eliminate all emergencies that occurred within the system. Fault-tolerant access control polices are used to address failure in emergency management. A case study of the hospital medical care application shows the effectiveness of FEAC.

  19. Functional Communication Training in the Treatment of Problem Behavior Maintained by Access to Rituals

    Science.gov (United States)

    Rispoli, Mandy; Camargo, Síglia; Machalicek, Wendy; Lang, Russell; Sigafoos, Jeff

    2014-01-01

    This study evaluated the assessment and treatment of problem behaviors related to rituals for children with autism. After functional analyses, we used a multiple-probe design to examine the effects of functional communication training (FCT) plus extinction and schedule thinning as a treatment package for problem behavior and appropriate…

  20. Access to Communication for Deaf, Hard-of-Hearing and ESL Students in Blended Learning Courses

    Science.gov (United States)

    Long, Gary L.; Vignare, Karen; Rappold, Raychel P.; Mallory, Jim

    2007-01-01

    In an effort to better understand student perceptions of communication in blended (online and traditional) learning courses, a 22 item questionnaire was developed and sent to all students registered for these courses at a large technology-focused college during three quarters of instruction. The respondents were divided into four groups: 1)…

  1. Massive Machine-Type Communication (mMTC) Access with Integrated Authentication

    DEFF Research Database (Denmark)

    Pratas, Nuno; Pattathil, Sarath; Stefanovic, Cedomir

    2017-01-01

    We present a connection establishment protocol with integrated authentication, suited for Massive Machine-Type Communications (mMTC). The protocol is contention-based and its main feature is that a device contends with a unique signature that also enables the authentication of the device towards...

  2. ICT and accessibility: an action space perspective on the impact of new information and communication technologies

    NARCIS (Netherlands)

    Dijst, M.J.

    2004-01-01

    It is frequently asserted in the literature that new Information and Communication Technologies (ICTs) are on the point of a breakthrough into rapid growth. Although we cannot say whether this breakthrough will indeed take place and ― should it do so ― on what scale, in this paper we nevertheless an

  3. ICT and accessibility: an action space perspective on the impact of new information and communication technologies

    NARCIS (Netherlands)

    Dijst, M.J.

    2004-01-01

    It is frequently asserted in the literature that new Information and Communication Technologies (ICTs) are on the point of a breakthrough into rapid growth. Although we cannot say whether this breakthrough will indeed take place and ― should it do so ― on what scale, in this paper we nevertheless

  4. Remote Control for Robotic Systems Using CORBA as Communication Architecture

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper proposes a novel method to implement network connections among a client and remoterobotic systems using CORBA for developing telecare system to aid the aged or disabled. The proposed methodmakes system have low cost and wide availability, high scaling and inter-operating ability to allow the clients andserver objects, written in different languages, run in different operating system, and connected in different net-work to inter-operate. It also makes system easy to be extended and integrated with the other technologies andapplications distributed over the Internet. Using CORBA as a communication architecture, we developed hard-ware base, task-level robot arm control server, live image feedback server and mobile robot control server,which can provide some basic care services to aid the aged and disabled.

  5. Dependability analysis of the data communication system in train control system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Communication based train control (CBTC) system is based on mobile communication and overcomes fixed blocks in order to increase track utilization and train safety. The data communication system (DCS) between trains and wayside equipment is a crucial factor for the safe and efficient operation of CBTC system. The dependability under various transmission conditions needs to be modeled and evaluated. In this paper,a stochastic reward net (SRN) model for DCS based IEEE 802.11 standard was developed,which captures all relevant failure and failure recovery behavior system aspects in a concise way. We compared the reliability,availability for DCS with and without access point (AP) and antenna redundant configuration. We also quantitatively evaluated and compared the frame loss probability for three DCS configurations with different train velocities and train numbers in one radio cell. Fixed-point iteration was adopted to simplify the analysis. Numerical results showed the significant improvement of the reliability,availability and the frame loss probability index for the full redundant configuration.

  6. Advanced Data Communications for Downhole Data Logging and Control Applications in the Oil Industry

    Science.gov (United States)

    Spracklen, C. T.; Aslam, Tariq

    2013-12-01

    We present details of 'Mercury', a high-speed downhole communications system that utilizes the (metallic) wall of a gas or oil pipeline or a drill 'string' as the communications 'channel' to control or monitor equipment or sensors used in the oil industry. Conventional downhole communication systems typically use 'mud pulse' telemetry for 'Measurement While Drilling' (MWD) operations. Current mud pulse telemetry technology offers bandwidths of up to 40 bit/s. However the data rate drops with increasing length of the wellbore and is typically as low as 1.5 bit/s - 3.0 bit/s at a depth of 35,000 ft. - 40,000 ft. The system described, by contrast, offers data rates of several megabits per second over distances of many kilometres and uses Orthogonal Frequency Division Multiplexing (OFDM) coupled with Wideband Frequency Division Multiple Access (W-CDMA). This paper presents details of our system; results of several trials undertaken on actual gas pipelines in the UK will be presented at the Conference.

  7. Dependability analysis of the data communication system in train control system

    Institute of Scientific and Technical Information of China (English)

    XU TanHua; TANG Tao; GAO ChunHai; CAI BaiGen

    2009-01-01

    Communication based train control (CBTC) system is based on mobile communication and overcomes fixed blocks in order to increase track utilization and train safety. The data communication system (DCS) between trains and wayside equipment is a crucial factor for the safe and efficient operation of CBTC system. The dependability under various transmission conditions needs to be modeled and evaluated. In this paper, a stochastic reward net (SRN) model for DCS based IEEE 802.11 standard was developed, which captures all relevant failure and failure recovery behavior system aspects in a concise way. We compared the reliability, availability for DCS with and without access point (AP) and antenna redundant configuration. We also quantitatively evaluated and compared the frame loss probability for three DCS configurations with different train velocities and train numbers in one radio cell. Fixed-point iteration was adopted to simplify the analysis. Numerical results showed the significant improvement of the reliability, availability and the frame loss probability index for the full redundant configuration.

  8. Proximity-based access control for context-sensitive information provision in SOA-based systems

    Science.gov (United States)

    Rajappan, Gowri; Wang, Xiaofei; Grant, Robert; Paulini, Matthew

    2014-06-01

    Service Oriented Architecture (SOA) has enabled open-architecture integration of applications within an enterprise. For net-centric Command and Control (C2), this elucidates information sharing between applications and users, a critical requirement for mission success. The Information Technology (IT) access control schemes, which arbitrate who gets access to what information, do not yet have the contextual knowledge to dynamically allow this information sharing to happen dynamically. The access control might prevent legitimate users from accessing information relevant to the current mission context, since this context may be very different from the context for which the access privileges were configured. We evaluate a pair of data relevance measures - proximity and risk - and use these as the basis of dynamic access control. Proximity is a measure of the strength of connection between the user and the resource. However, proximity is not sufficient, since some data might have a negative impact, if leaked, which far outweighs importance to the subject's mission. For this, we use a risk measure to quantify the downside of data compromise. Given these contextual measures of proximity and risk, we investigate extending Attribute-Based Access Control (ABAC), which is used by the Department of Defense, and Role-Based Access Control (RBAC), which is widely used in the civilian market, so that these standards-based access control models are given contextual knowledge to enable dynamic information sharing. Furthermore, we consider the use of such a contextual access control scheme in a SOA-based environment, in particular for net-centric C2.

  9. Institutional Repositories and Open Access Initiatives in Bangladesh: A New Paradigm of Scholarly Communication

    Directory of Open Access Journals (Sweden)

    Md. Anwarul Islam

    2013-06-01

    Full Text Available Nowadays, open access (OA in its diverse forms constitutes the most interesting and promising model for the research output of an academic or research institution. The purpose of the present study is to discuss the situation of OA in the developing world, with a focus on Bangladesh. The study also addresses why OA is important for developing countries and which initiatives have been taken in Bangladesh. Finally, we discuss some challenging issues of OA and suggestions on how to overcome these issues. It is rather obvious that developing countries have always faced a lack of research information and were unable to afford sufficient subscriptions to journals. The other side of the picture is the poor dissemination of the research outcome in the developing world. In Bangladesh, only three organizations have their institutional repository and have a reasonable number of local OA journals. We will identify some problems that impede the process of building open access IR, or more generally an OA environment in Bangladesh. We are convinced, however, that we will witness in the near future a sustainable growth of open access initiatives, with more open access literature and digital repositories.

  10. Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Abdul Razaque

    2014-03-01

    -synchronous feature with a low duty cycle, which is advantageous for reducing the latency and energy consumption for several WSN application areas to improve the throughput. BN-MAC uses a unique window slot size to enhance the contention resolution issue for improved throughput. BN-MAC also prefers to communicate within a one-hop destination using Anycast, which maintains load balancing to maintain network reliability. BN-MAC is introduced with the goal of supporting four major application areas: monitoring and behavioral areas, controlling natural disasters, human-centric applications, and tracking mobility and static home automation devices from remote places. These application areas require a congestion-free mobility-supported MAC protocol to guarantee reliable data delivery. BN-MAC was evaluated using network simulator-2 (ns2 and compared with other hybrid MAC protocols, such as Zebra medium access control (Z-MAC, advertisement-based MAC (A-MAC, Speck-MAC, adaptive duty cycle SMAC (ADC-SMAC, and low-power real-time medium access control (LPR-MAC. The simulation results indicate that BN-MAC is a robust and energy-efficient protocol that outperforms other hybrid MAC protocols in the context of quality of service (QoS parameters, such as energy consumption, latency, throughput, channel access time, successful delivery rate, coverage efficiency, and average duty cycle.

  11. Energy-efficient boarder node medium access control protocol for wireless sensor networks.

    Science.gov (United States)

    Razaque, Abdul; Elleithy, Khaled M

    2014-03-12

    -synchronous feature with a low duty cycle, which is advantageous for reducing the latency and energy consumption for several WSN application areas to improve the throughput. BN-MAC uses a unique window slot size to enhance the contention resolution issue for improved throughput. BN-MAC also prefers to communicate within a one-hop destination using Anycast, which maintains load balancing to maintain network reliability. BN-MAC is introduced with the goal of supporting four major application areas: monitoring and behavioral areas, controlling natural disasters, human-centric applications, and tracking mobility and static home automation devices from remote places. These application areas require a congestion-free mobility-supported MAC protocol to guarantee reliable data delivery. BN-MAC was evaluated using network simulator-2 (ns2) and compared with other hybrid MAC protocols, such as Zebra medium access control (Z-MAC), advertisement-based MAC (A-MAC), Speck-MAC, adaptive duty cycle SMAC (ADC-SMAC), and low-power real-time medium access control (LPR-MAC). The simulation results indicate that BN-MAC is a robust and energy-efficient protocol that outperforms other hybrid MAC protocols in the context of quality of service (QoS) parameters, such as energy consumption, latency, throughput, channel access time, successful delivery rate, coverage efficiency, and average duty cycle.

  12. A cross-layer communication framework for wireless networked control systems

    NARCIS (Netherlands)

    Israr, N.; Scanlon, W.G.; Irwin, G.W.

    2009-01-01

    This paper presents a robust, dynamic cross-layer wireless communication architecture for wireless networked control systems. Each layer in the proposed protocol architecture contributes to the overall goal of reliable, energy efficient communication. The protocol stack also features a

  13. Fertility effects of abortion and birth control pill access for minors.

    Science.gov (United States)

    Guldi, Melanie

    2008-11-01

    This article empirically assesses whether age-restricted access to abortion and the birth control pill influence minors' fertility in the United States. There is not a strong consensus in previous literature regarding the relationship between laws restricting minors' access to abortion and minors' birth rates. This is the first study to recognize that state laws in place prior to the 1973 Roe v. Wade decision enabled minors to legally consent to surgical treatment-including abortion-in some states but not in others, and to construct abortion access variables reflecting this. In this article, age-specific policy variables measure either a minor's legal ability to obtain an abortion or to obtain the birth control pill without parental involvement. I find fairly strong evidence that young women's birth rates dropped as a result of abortion access as well as evidence that birth control pill access led to a drop in birth rates among whites.

  14. Access to "Jiggasha program: a family planning communication approach" and its exposure to the selected background characteristics.

    Science.gov (United States)

    Hossain, M W; Khan, H T; Begum, A

    1999-06-01

    This paper studies the effectiveness of "Jiggasha," an innovative communication approach for the promotion of family planning in Dhaka, Bangladesh. Data from the 1996 Jiggasha follow-up survey were used, which gathered information by interviewing a network sample of 1862 married women and a subsample of 608 men. The study used the sample constituted by women respondents and included data on socioeconomic and demographic characteristics of the respondents and their knowledge, attitude and practice relating to contraceptives. Findings showed that Jiggasha respondents have more access to radio than television. All respondents reported having a radio in their homes and they emphasized the importance of broadcasting more family planning messages via both electronic media. Only 16% of the women in the study setting were exposed to group meetings. Of the respondents reporting participation in group meetings, 38.25% joined in a Jiggasha meeting, 23.15% in a Grameen Bank group meeting, and 4.70% in a Bangladesh Rural Advancement Committee group meeting. Logistic regression analysis indicated more access to Jiggashas among women over 30 years of age than among the younger age groups. Religion and education levels of respondents have significant impact on access to Jiggashas. Husbands' approval plays an important role among the Jiggasha respondents in using family planning method. This study provides important information for policy-makers to make family planning program a success.

  15. Assessment of current practices in creating and using passwords as a control mechanism for information access

    Directory of Open Access Journals (Sweden)

    P. L. Wessels

    2007-11-01

    Full Text Available One of the critical issues in managing information within an organization is to ensure that proper controls exist and are applied in allowing people access to information. Passwords are used extensively as the main control mechanism to identify users wanting access to systems, applications, data files, network servers or personal information. In this article, the issues involved in selecting and using passwords are discussed and the current practices employed by users in creating and storing passwords to gain access to sensitive information are assessed. The results of this survey conclude that information managers cannot rely only on users to employ proper password control in order to protect sensitive information.

  16. A Distributed Architecture for Sharing Ecological Data Sets with Access and Usage Control Guarantees

    DEFF Research Database (Denmark)

    Bonnet, Philippe; Gonzalez, Javier; Granados, Joel Andres

    2014-01-01

    and usage control is necessary to enforce existing open data policies. We have proposed the vision of trusted cells: A decentralized infrastructure, based on secure hardware running on devices equipped with trusted execution environments at the edges of the Internet. We originally described the utilization...... new insights, there are signicant barriers to the realization of this vision. One of the key challenge is to allow scientists to share their data widely while retaining some form of control over who accesses this data (access control) and more importantly how it is used (usage control). Access...... data sets with access and usage control guarantees. We rely on examples from terrestrial research and monitoring in the arctic in the context of the INTERACT project....

  17. Security Analysis and Improvements of Authentication and Access Control in the Internet of Things

    Directory of Open Access Journals (Sweden)

    Bruce Ndibanje

    2014-08-01

    Full Text Available Internet of Things is a ubiquitous concept where physical objects are connected over the internet and are provided with unique identifiers to enable their self-identification to other devices and the ability to continuously generate data and transmit it over a network. Hence, the security of the network, data and sensor devices is a paramount concern in the IoT network as it grows very fast in terms of exchanged data and interconnected sensor nodes. This paper analyses the authentication and access control method using in the Internet of Things presented by Jing et al. According to our analysis, Jing et al.’s protocol is costly in the message exchange and the security assessment is not strong enough for such a protocol. Therefore, we propose improvements to the protocol to fill the discovered weakness gaps. The protocol enhancements facilitate many services to the users such as user anonymity, mutual authentication, and secure session key establishment. Finally, the performance and security analysis show that the improved protocol possesses many advantages against popular attacks, and achieves better efficiency at low communication cost.

  18. Linear programming and algorithms for communication networks a practical guide to network design, control, and management

    CERN Document Server

    Oki, Eiji

    2012-01-01

    Explaining how to apply to mathematical programming to network design and control, Linear Programming and Algorithms for Communication Networks: A Practical Guide to Network Design, Control, and Management fills the gap between mathematical programming theory and its implementation in communication networks. From the basics all the way through to more advanced concepts, its comprehensive coverage provides readers with a solid foundation in mathematical programming for communication networks. Addressing optimization problems for communication networks, including the shortest path problem, max f

  19. Computer Program Development Specification Terminal Access Controller. Appendix B. Access Line Modes.

    Science.gov (United States)

    1979-04-06

    CG-510262 Part 1 of 2 6 April 1979 Page B17 iS U £ 44 0 o a, U, 00 0 ,.- C 2 50 St -: 2-, CG-510262 Part 1 of 2 6 April 1979 Page B18 00 0 0 0 4 4 0...receipt of RM as the response to a block and acknowledged wit , receive control character ACK2. CAN is never transmitted wit’iin t-ne text portion of a

  20. Massive Access Control Aided by Knowledge-Extraction for Co-Existing Periodic and Random Services over Wireless Clinical Networks.

    Science.gov (United States)

    Du, Qinghe; Zhao, Weidong; Li, Weimin; Zhang, Xuelin; Sun, Bo; Song, Houbing; Ren, Pinyi; Sun, Li; Wang, Yichen

    2016-07-01

    The prosperity of e-health is boosted by fast development of medical devices with wireless communications capability such as wearable devices, tiny sensors, monitoring equipments, etc., which are randomly distributed in clinic environments. The drastically-increasing population of such devices imposes new challenges on the limited wireless resources. To relieve this problem, key knowledge needs to be extracted from massive connection attempts dispersed in the air towards efficient access control. In this paper, a hybrid periodic-random massive access (HPRMA) scheme for wireless clinical networks employing ultra-narrow band (UNB) techniques is proposed. In particular, the proposed scheme towards accommodating a large population of devices include the following new features. On one hand, it can dynamically adjust the resource allocated for coexisting periodic and random services based on the traffic load learned from signal collision status. On the other hand, the resource allocation within periodic services is thoroughly designed to simultaneously align with the timing requests of differentiated services. Abundant simulation results are also presented to demonstrate the superiority of the proposed HPRMA scheme over baseline schemes including time-division multiple access (TDMA) and random access approach, in terms of channel utilization efficiency, packet drop ratio, etc., for the support of massive devices' services.

  1. Patients' communication with doctors: a randomized control study of a brief patient communication intervention.

    Science.gov (United States)

    Talen, Mary R; Muller-Held, Christine F; Eshleman, Kate Grampp; Stephens, Lorraine

    2011-09-01

    In research on doctor-patient communication, the patient role in the communication process has received little attention. The dynamic interactions of shared decision making and partnership styles which involve active patient communication are becoming a growing area of focus in doctor-patient communication. However, patients rarely know what makes "good communication" with medical providers and even fewer have received coaching in this type of communication. In this study, 180 patients were randomly assigned to either an intervention group using a written communication tool to facilitate doctor-patient communication or to standard care. The goal of this intervention was to assist patients in becoming more effective communicators with their physicians. The physicians and patients both rated the quality of the communication after the office visit based on the patients' knowledge of their health concerns, organizational skills and questions, and attitudes of ownership and partnership. The results supported that patients in the intervention group had significantly better communication with their doctors than patients in the standard care condition. Physicians also rated patients who were in the intervention group as having better overall communication and organizational skills, and a more positive attitude during the office visit. This study supports that helping patients structure their communication using a written format can facilitate doctor-patient communication. Patients can become more adept at describing their health concerns, organizing their needs and questions, and being proactive, which can have a positive effect on the quality of the doctor-patient communication during outpatient office visits. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  2. Enhancing Subject Access to OPACs: Controlled Vocabulary vs. Natural Language.

    Science.gov (United States)

    Cousins, Shirley Anne

    1992-01-01

    Investigation of retrieval performance of controlled vocabulary derived from natural language terms in tables of contents and book indexes assumed that controlled vocabulary representative of users' queries should adequately represent documents' contents. Queries were indexed using Library of Congress Subject Headings (LSCH), Dewey Decimal…

  3. Optically controlled phased-array antenna with PSK communications

    Science.gov (United States)

    Cooper, Martin J.; Sample, Peter; Lewis, Meirion F.; Wilson, Rebecca A.

    2004-11-01

    An optically controlled RF/microwave/mm-wave phased array antenna has been developed operating at 10 GHz with 30 kHz reconfiguration rate via the use of a micromachined silicon Spatial Light Modulator. A communications function has been demonstrated with a variety of Phase Shift Keying modulation schemes (BPSK, QPSK, MSK) at data rates up to 200 Mbit/s and low BER (<1×10-9). A single channel has been demonstrated at 35 GHz. The properties of photonic components are taken advantage of in several ways: (i) since the carrier frequency is derived from heterodyning of lasers, it is tuneable from almost DC-100 GHz, (ii) the use of optical fiber allows for EMI immune antenna remoting, and (iii) the wide information bandwidth of optical modulators, which in this configuration is carrier frequency independent. The above is achieved in a lightweight and compact format, with considerable scope for further reductions in size and weight.

  4. Disabled people and accessibility: How successful is Slovenia in the elimination and prevention of built-environment and communication barriers?

    Directory of Open Access Journals (Sweden)

    Richard Sendi

    2009-01-01

    Full Text Available The Urban Planning Institute of the Republic of Slovenia and the Institute of the Republic of Slovenia for Social Protection, together conducted a research project entitled Measures for the realisation of the rights of the disabled to barrier-free access which was concluded in December 2008. The research was funded jointly by the Slovenian Research Agency and the Ministry of Labour, Family and Social Affairs. The main aim of the research was to conduct an extensive analysis of the state of care for persons with disabilities in Slovenia. This involved analysing the accessibility of the built environment and accessibility of communication and information, as well as investigating the efficiency of implementation of the policies and measures that were adopted at the national level for guaranteeing disabled persons barrier-free movement and social inclusion. The main part of the research is constituted of two field surveys, one conducted among individual disabled persons and the other conducted among the major disabled people’s organisation in Slovenia. On the basis of a preliminary literature review and a review of the current legislation and policies concerning the disabled, the guiding hypothesis for the survey was that very little has been done, so far, towards the realisation of the rights of the disabled which are declared in the various national documents. The results of the empirical research provide evidence in support of this hypothesis. In this paper, we present the results of both field surveys, give a summary of the major findings and, in conclusion, suggest some measures that need to be implemented in order to ensure greater efficiency of the realisation of the rights of the disabled to barrier-free access.

  5. Optical Wireless Communications and Autonomous Beam Control Moving User Terminal

    OpenAIRE

    Tangtrongbenchasil, Charoen; HAMADA, Yoichi; KATO, Toshihiro; Nonaka, Koji

    2007-01-01

    Optical wireless communications is a research topic of extreme interest since it offers high data rate (Gbps data rate), security, and RF interference immunity. However, optical wireless communications places severe restrictions on the communications paths; they must be direct beam connections. To increase the number of users and link robustness, optical wireless communications must be able to operate even when obstacles are placed between transmitters and receivers, so optical micro-cell (OM...

  6. Social responsibility and educational communication in communities accessed by the works: a case study. IEGA - enterprise implementations for gasene

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Elisangela Assis de; Farias, Aline Marianne Magalhaes [LP Empreendimentos, Rio de janeiro, RJ (Brazil); Marques, Yanna Oliveira [Cia. Nacional de Dutos (Conduto S/A), Duque de Caxias, RJ (Brazil); Penido, Rita de Cassia [Sinopec Brasil, Rio de Janeiro, RJ (Brazil)

    2009-12-19

    Construction and assembly in a gas pipeline project is a constant study of realities and in some cases situations which involve interferences in communities, the company's interests must be wholly integrated with the primary need of the project which is to construct with Social-Environmental Responsibility, establish a good relationship, respect the communities values in which the project passes through and around and surround itself with measures guaranteeing safety, information about the activities and cause minimal impact in the day to day lives of the residents. At Spread 2A of the Pipeline project Cacimbas-Catu, the necessity to develop a specific project for the communities surrounding the access areas was elaborated principally because the topography only permitted the transportation of pipes, equipment and personnel to pass through these areas. This unique situation was drafted based on the transit of vehicles and heavy machinery, through communities with a low IDH (Human Development Index), dangerous living conditions and a high demographic density. Preventive and pacifying actions for Communities and Social responsibility were drafted and developed, involving a multidisciplinary collective effort with other sectors of the project, applying a global theme to ensure safety for the residents around the access areas, also to divulge information in regards to project activities, establish ethical and transparent communication and implement measures that assist in building a solid relationship between the enterprise and community, anticipating risky situations and possible conflicts. This Case Study has as an objective to present projects that were developed in the area of Communication and Social Responsibility in the Access Communities and that, proved effective, became standard within the entire work force's Trainings and Daily Safety, Environmental, and Occupational Health Dialoguing. During the development of the Project 'Street of Leisure

  7. Inter-Vehicle Communication System Utilizing Autonomous Distributed Transmit Power Control

    Science.gov (United States)

    Hamada, Yuji; Sawa, Yoshitsugu; Goto, Yukio; Kumazawa, Hiroyuki

    In ad-hoc network such as inter-vehicle communication (IVC) system, safety applications that vehicles broadcast the information such as car velocity, position and so on periodically are considered. In these applications, if there are many vehicles broadcast data in a communication area, congestion incurs a problem decreasing communication reliability. We propose autonomous distributed transmit power control method to keep high communication reliability. In this method, each vehicle controls its transmit power using feed back control. Furthermore, we design a communication protocol to realize the proposed method, and we evaluate the effectiveness of proposed method using computer simulation.

  8. 77 FR 26789 - Certain Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and...

    Science.gov (United States)

    2012-05-07

    ... From the Federal Register Online via the Government Publishing Office ] INTERNATIONAL TRADE COMMISSION Certain Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and Products Containing Same; Determination Rescinding the Exclusion Order and Cease and Desist Orders...

  9. Role-Based Access Control for the Large Hadron Collider at CERN

    CERN Document Server

    Yastrebov, I

    2010-01-01

    Large Hadron Collider (LHC) is the largest scientific instrument ever created. It was built with the intention of testing the most extreme conditions of the matter. Taking into account the significant dangers of LHC operations, European Organization for Nuclear Research (CERN) has developed multi-pronged approach for machine safety, including access control system. This system is based on role-based access control (RBAC) concept. It was designed to protect from accidental and unauthorized access to the LHC and injector equipment. This paper introduces the new model of the role-based access control developed at CERN and gives detailed mathematical description of it. We propose a new technique called dynamic authorization that allows deploying RBAC gradually in the large systems. Moreover, we show how the protection for the very large distributed equipment control system may be implemented in efficient way. This paper also describes motivation of the project, requirements and overview of the main components: au...

  10. The Design of the M-B-Quadro Optical Switch and Its Access Control Strategies

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper proposes a new simple contention resolution switching architecture, M-B-Quadro, and its underlying access control strategies. By incorporating delay and buffer lines, the switching node can effectively obtain very low packet deflection probability.

  11. Multi-model-based Access Control in Construction Projects

    CERN Document Server

    Hilbert, Frank; Araujo, Larissa; 10.4204/EPTCS.83.1

    2012-01-01

    During the execution of large scale construction projects performed by Virtual Organizations (VO), relatively complex technical models have to be exchanged between the VO members. For linking the trade and transfer of these models, a so-called multi-model container format was developed. Considering the different skills and tasks of the involved partners, it is not necessary for them to know all the models in every technical detailing. Furthermore, the model size can lead to a delay in communication. In this paper an approach is presented for defining model cut-outs according to the current project context. Dynamic dependencies to the project context as well as static dependencies on the organizational structure are mapped in a context-sensitive rule. As a result, an approach for dynamic filtering of multi-models is obtained which ensures, together with a filtering service, that the involved VO members get a simplified view of complex multi-models as well as sufficient permissions depending on their tasks.

  12. Multi-model-based Access Control in Construction Projects

    Directory of Open Access Journals (Sweden)

    Frank Hilbert

    2012-04-01

    Full Text Available During the execution of large scale construction projects performed by Virtual Organizations (VO, relatively complex technical models have to be exchanged between the VO members. For linking the trade and transfer of these models, a so-called multi-model container format was developed. Considering the different skills and tasks of the involved partners, it is not necessary for them to know all the models in every technical detailing. Furthermore, the model size can lead to a delay in communication. In this paper an approach is presented for defining model cut-outs according to the current project context. Dynamic dependencies to the project context as well as static dependencies on the organizational structure are mapped in a context-sensitive rule. As a result, an approach for dynamic filtering of multi-models is obtained which ensures, together with a filtering service, that the involved VO members get a simplified view of complex multi-models as well as sufficient permissions depending on their tasks.

  13. Test-bed Assessment of Communication Technologies for a Power-Balancing Controller

    DEFF Research Database (Denmark)

    Findrik, Mislav; Pedersen, Rasmus; Hasenleithner, Eduard

    2016-01-01

    Due to growing need for sustainable energy, increasing number of different renewable energy resources are being connected into distribution grids. In order to efficiently manage a decentralized power generation units, the smart grid will rely on communication networks for information exchange...... and control. In this paper, we present a Smart Grid test-bed that integrates various communication technologies and deploys a power balancing controller for LV grids. Control performance of the introduced power balancing controller is subsequently investigated and its robustness to communication network cross......-traffic is evaluated. Various scenarios are demonstrated, assessing impact of communication network performance on quality of control....

  14. Distributed Medium Access Control with SDMA Support for WLANs

    Science.gov (United States)

    Zhou, Sheng; Niu, Zhisheng

    With simultaneous multi-user transmissions, spatial division multiple access (SDMA) provides substantial throughput gain over the single user transmission. However, its implementation in WLANs with contention-based IEEE 802.11 MAC remains challenging. Problems such as coordinating and synchronizing the multiple users need to be solved in a distributed way. In this paper, we propose a distributed MAC protocol for WLANs with SDMA support. A dual-mode CTS responding mechanism is designed to accomplish the channel estimation and user synchronization required for SDMA. We analytically study the throughput performance of the proposed MAC, and dynamic parameter adjustment is designed to enhance the protocol efficiency. In addition, the proposed MAC protocol does not rely on specific physical layer realizations, and can work on legacy IEEE 802.11 equipment with slight software updates. Simulation results show that the proposed MAC outperforms IEEE 802.11 significantly, and that the dynamic parameter adjustment can effectively track the load variation in the network.

  15. Access Control in the ATLAS TDAQ Online Cluster

    CERN Document Server

    Leahu, Marius Constantin; Stoichescu, D A; Lehmann Miotto, G

    ATLAS (A Toroidal LHC Apparatus) is a general-purpose detector for studying high-energy particle interactions: it is the largest particle detector experiment at CERN and it is built around one of the interaction points of the proton beams accelerated by the Large Hadron Collider (LHC). The detector generates an impressive amount of raw data: 64 TB per second as a result of 40 MHz proton-proton collision rate with 1.6 MB data for each such event. The handling of such data rate is managed by a three levels Trigger and Data Acquisition (TDAQ) system, which filters out the events not relevant from physics research point of view and selects in the end in the order of 1000 events per second to be stored for offline analyses. This system comprises a significant number of hardware devices, software applications and human personnel to supervise the experiment operation. Their protection against damages as a result of misuse and their optimized exploitation by avoiding the conflicting accesses to resources are key requ...

  16. Smart packet access and call admission control for efficient resource management in advanced wireless networks

    OpenAIRE

    Phan, V. V. (Vinh V.)

    2005-01-01

    Abstract Efficient management of rather limited resources, including radio spectrum and mobile-terminal battery power, has been the fundamental design challenge of wireless networks and one of the most widespread research problems over the years. MAC (Medium Access Control) for packet access and CAC (Call Admission Control) for connection-oriented service domains are commonly used as effective tools to manage radio resources, capacity and performance of wireless networks while providing ad...

  17. Intelligent Security Auditing Based on Access Control of Devices in Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    XU Guang-wei; SHI You-qun; ZHU Ming; WU Guo-wen; CAO Qi-ying

    2006-01-01

    Security in Ad Hoc network is an important issue under the opening circumstance of application service. Some protocols and models of security auditing have been proposed to ensure rationality of contracting strategy and operating regulation and used to identify abnormal operation. Model of security auditing based on access control of devices will be advanced to register sign of devices and property of event of access control and to audit those actions. In the end, the model is analyzed and simulated.

  18. Springfield Processing Plant* (A Hypothetical Facility) SPP, Entry Control Point and Vehicle Gate Access Control Post Order

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Gregory A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2014-06-01

    This hypothetical order provides the requirements and instructions for the Springfield Processing Plant (SPP) Vehicle Gate and Entry Control Point (ECP) in the perimeter access building. The purpose of this post is to prevent the theft, sabotage or diversion of nuclear material (NM), control access and exit at the protected area, and to respond to emergencies according the SPP Guard Force (GF) Contingency Plan and as directed by a Guard Force Supervisor.

  19. 面向协作通信的忙音信道接入机制%A channel accessing scheme based on busy tone for cooperative communication

    Institute of Scientific and Technical Information of China (English)

    谢鲲; 谢可欣; 吉刚; 何施茗

    2014-01-01

    Compared with traditional wireless communication , although relay nodes in cooperative communication can help to increase the performance of a wireless network,relay nodes may cause the serious competition for wire-less channel accessing ,which makes the channel access problem in cooperative communication challenging .To solve the problem,a novel MAC ( media access control) scheme by concurrently considering RTS/CTS ( Request To Send/Clear To Send) and busy tone is proposed in the paper.In the scheme,three busy tones are proposed to iden-tify the state of channel occupation and solve the hidden terminal and exposed terminal problems in cooperative communication.Based on the busy tone,this paper also proposes a bandwidth efficient relay selection algorithm.The source can choose the best relay in a distributed way by sensing the busy tone .The theory and simulation results demonstrate that the proposed scheme can efficiently improve the channel utilization and solve the hidden terminal and exposed terminal problems in cooperative communication .The blocking time ratio of the proposed MAC scheme is less than 10% when the data packet size surpasses 3500B.%与传统无线传输相比,虽然协作中继节点的参与可以大大提高无线网络性能,然而协作中继会带来严重的信道竞争问题,这给协作通信环境中的信道访问控制带来挑战。为了解决这个问题,提出一种RTS/CTS(Request To Send/Clear To Send)与忙音结合的MAC(media access control)信道接入方案。该方案使用3个忙音来标识信道的使用状态,并解决协作通信中的隐藏终端和暴露终端问题。基于忙音信号,还提出了一种带宽节俭的协作节点选择算法。通过侦听忙音信号,源节点可分布式地选择最优的协作节点。理论分析和仿真实验表明所提方案能有效地提高协作通信中的信道利用率,很好地解决了协作通信中的隐藏终端暴露终端问

  20. TEMPORAL, DELEGABLE AND CHEAP UPDATE ACCESS CONTROL TO PUBLISHED XML DOCUMENTS

    Directory of Open Access Journals (Sweden)

    Waleed Halboob

    2013-01-01

    Full Text Available Providing access control for published XML documents on the Web is an important topic. It involves the use of cryptographic techniques, addressing different requirements and, as a result, facing several challenges. Existing solutions still have some weaknesses such as system update cost, number of required secret encryption/decryption keys, size of encrypted document and supporting temporal and delegable access. This study propose a push--based access control policy enforcement mechanism for addressing these issues using a Dynamic Key Management Table (DKMT and based on Identity Based Encryption (IBE. The proposed mechanism addresses the existing challenges and provides a more acceptable solution.

  1. Unifying the Access Control Mechanism for the Enterprises Using XACML Policy Levels

    Directory of Open Access Journals (Sweden)

    N. Senthil Kumar

    2015-11-01

    Full Text Available —Many enterprises have intended to promote their applications with stern access control mechanism and yield the stringent authorization deployment in their individual proprietary manner. The development of this build up will result in tight coupling of authorization mechanisms within the enterprise applications. In many enterprises setup, the implicit authorization processes are embedded within the application and promote error prone accessing of requested policies. This sort of embedded authorization will let the users to carry out the specific actions without knowing the access control policy as well as its embedded setup with the help of third party involvement. But this approach has some serious effects in controlling the issues such as skipping the trust based applications, violates the policy setups and pave the way to exploit the authorized data to the end users. Many enterprises had faced serious problem in controlling its sensitive data from this implicit authorization decisions and hence decided to develop a security mechanism which can be totally controlled by centralized way of access policy. Therefore, the eXtensible Access Control Markup Language (XACML provides a very simple and powerful remedy for authorization mechanism and for the access policy set ups.

  2. Integrated Antenna/Solar Array Cell (IA/SAC) System for Flexible Access Communications

    Science.gov (United States)

    Lee, Ricard Q.; Clark, Eric B.; Pal, Anna Maria T.; Wilt, David M.; Mueller, Carl H.

    2004-01-01

    Present satellite communications systems normally use separate solar cells and antennas. Since solar cells generally account for the largest surface area of the spacecraft, co-locating the antenna and solar cells on the same substrate opens the possibility for a number of data-rate-enhancing communications link architecture that would have minimal impact on spacecraft weight and size. The idea of integrating printed planar antenna and solar array cells on the same surface has been reported in the literature. The early work merely attempted to demonstrate the feasibility by placing commercial solar cells besides a patch antenna. Recently, Integrating multiple antenna elements and solar cell arrays on the same surface was reported for both space and terrestrial applications. The application of photovoltaic solar cell in a planar antenna structure where the radiating patch antenna is replaced by a Si solar cell has been demonstrated in wireless communication systems (C. Bendel, J. Kirchhof and N. Henze, 3rd Would Photovotaic Congress, Osaka, Japan, May 2003). Based on a hybrid approach, a 6x1 slot array with circularly polarized crossdipole elements co-located on the same surface of the solar cells array has been demonstrated (S. Vaccaro, J. R. Mosig and P. de Maagt, IEEE Trans. Ant. and Propag., Vol. 5 1, No. 8, Aug. 2003). Amorphous silicon solar cells with about 5-10% efficiency were used in these demonstrations. This paper describes recent effort to integrate advanced solar cells with printed planar antennas. Compared to prior art, the proposed WSAC concept is unique in the following ways: 1) Active antenna element will be used to achieve dynamic beam steering; 2) High efficiency (30%) GaAs multi-junction solar cells will be used instead of Si, which has an efficiency of about 15%; 3) Antenna and solar cells are integrated on a common GaAs substrate; and 4) Higher data rate capability. The IA/SAC is designed to operate at X-band (8-12 GH) and higher frequencies

  3. Interface of the transport systems research vehicle monochrome display system to the digital autonomous terminal access communication data bus

    Science.gov (United States)

    Easley, W. C.; Tanguy, J. S.

    1986-01-01

    An upgrade of the transport systems research vehicle (TSRV) experimental flight system retained the original monochrome display system. The original host computer was replaced with a Norden 11/70, a new digital autonomous terminal access communication (DATAC) data bus was installed for data transfer between display system and host, while a new data interface method was required. The new display data interface uses four split phase bipolar (SPBP) serial busses. The DATAC bus uses a shared interface ram (SIR) for intermediate storage of its data transfer. A display interface unit (DIU) was designed and configured to read from and write to the SIR to properly convert the data from parallel to SPBP serial and vice versa. It is found that separation of data for use by each SPBP bus and synchronization of data tranfer throughout the entire experimental flight system are major problems which require solution in DIU design. The techniques used to accomplish these new data interface requirements are described.

  4. Accessibility to information and communications technology for the social participation of youths with disabilities: a two-way street.

    Science.gov (United States)

    Schreuer, Naomi; Keter, Ayala; Sachs, Dalia

    2014-01-01

    The current study examined by mixed method the effectiveness of an accessibility to Information and Communications Technology (ICT) program that provided computers, assistive technology, tutors, and internet connection to 65 youths with severe disabilities (aged 13.22 ± 3.4 years) in their homes. The quantitative evaluation included assessment of computer task performance, computer skills, and participation in social ICT leisure activities before and after the program. Findings revealed low baseline and significant progress on most outcome measures 6 months after the program, mostly among those youths who had tutors. Additional in-depth interviews were conducted 1 year later with 10 participants to explore their ICT use and its impact on their social participation. The analysis revealed a significant contribution of the ICT use, while critical thinking about its risks and some disappointment with the social needs that ICT does not address. Our findings raise awareness of 'two-way streets' policies and programs to ensure e-inclusion.

  5. Placement of Base Stations in Broadband Power Line Communications Access Networks by Means of Multi-criteria Optimization

    Science.gov (United States)

    Haidine, Abdelfatteh; Lehnert, Ralf

    Broadband Power Line Communications (B-PLC) technology is an alternative for broadband access networks, allowing bit rates up to currently 200Mbps. This technique uses the wiring of the low-voltage grid in order to offer to the users the telecommunications services, such as Internet, VoIP, VoD, etc. The B-PLC design process is sub-divided into two parts: the Generalized Base Station Placement (GBSP) problem and the PLC Channel Allocation Problem (P-CAP). This paper focuses on GBSP that is modeled as multi-criteria combinatorial optimization problem. Based on our published mathematical modeling, this paper supplies more numerical experiments for the evaluation of Multi-Objective Evolutionary Algorithms (MOEAs) in solving GBSP. Their performance is compared with the single-objective optimization.

  6. [Access, use and preferences of Information and Communication Technologies by physicians in a general hospital in Peru].

    Science.gov (United States)

    Vásquez-Silva, Luis; Ticse, Ray; Alfaro-Carballido, Luz; Guerra-Castañon, Felix

    2015-01-01

    We assessed the access, use and preferences of information and communication technology (ICT) by physicians who practice at Cayetano Heredia National Hospital. The questionnaire explored the availability and skills of ICT, time, educational activities, search engines and technological applications most used as well as ICT preferences in education.211 physicians were surveyed; laptop use was 93%, tablet and smartphone use was 66% and 88%.68% have mobile Internet. Differences were evident in the frequency of use of ICT in 25-34 year old age group as well as a higher level of skills (paccess of ICT is common among doctors in this hospital and there is positive interest in its use in education.

  7. 76 FR 38293 - Risk Management Controls for Brokers or Dealers With Market Access

    Science.gov (United States)

    2011-06-30

    ... COMMISSION 17 CFR Part 240 RIN 3235-AK53 Risk Management Controls for Brokers or Dealers With Market Access... establish, document, and maintain a system of risk management controls and supervisory procedures that... develop, test, and implement the relevant risk management controls and supervisory procedures...

  8. GAME THEORY BASED INTERFERENCE CONTROL AND POWER CONTROL FOR D2D COMMUNICATION IN CELLULAR NETWORKS

    Directory of Open Access Journals (Sweden)

    Fa-Bin Li

    2016-09-01

    Full Text Available With the current development of mobile communication services, people need personal communication of high speed, excellent service, high quality and low latency,however, limited spectrum resources become the most important factor to hamper improvement of cellular systems. As big amount of data traffic will cause greater local consumption of spectrum resources, future networks are required to have appropriate techniques to better support such forms of communication. D2D (Device-to-device communication technology in a cellular network makes full use of spectrum resources underlaying, reduces the load of the base station, minimizes transmit power of the terminals and the base stations, thereby enhances the overall throughput of the networks. Due to the use of multiplexing D2D UE (User equipment resources and spectrum, and the interference caused by the sharing of resources between adjacent cells, it has become a major factor affecting coexisting of cellular subscribers and D2D users. When D2D communication multiplexes the uplink resources, the base-stations are easily to be disturbed; when the downlink resources are multiplexed, the users of downlink are susceptible to interference. In order to build a high-efficient mobile network, we can meet the QoS requirements by controlling the power to suppress the interference between the base station and a terminal user.

  9. Cognitive Control and Lexical Access in Younger and Older Bilinguals

    Science.gov (United States)

    Bialystok, Ellen; Craik, Fergus; Luk, Gigi

    2008-01-01

    Ninety-six participants, who were younger (20 years) or older (68 years) adults and either monolingual or bilingual, completed tasks assessing working memory, lexical retrieval, and executive control. Younger participants performed most of the tasks better than older participants, confirming the effect of aging on these processes. The effect of…

  10. The global spread of English, scientific communication and ESP: questions of equity, access and domain loss

    Directory of Open Access Journals (Sweden)

    Gibson Ferguson

    2007-04-01

    Full Text Available The emergence of English as the international language of scientific communication has been so amply documented (e.g. see Sano, 2002; Ammon, 2003 that its dominance is hardly disputed empirically even by those most critical of this state of affairs. More contested, however, are the effects of this dominance: with two sets of concerns particularly salient: (i the potential detrimental impact on other languages –even standardised national languages, which are at risk, so it is argued, of being relegated to a lesser role in an incipient global diglossia and of losing domains; and (ii the communicative inequality produced by the dominance of English between, in particular, native-speaking scientists/academics and non-native scientists, the latter experiencing relative disadvantage, it is sometimes claimed, when it comes to placing their work in high prestige international journals. This paper investigates both these concerns drawing on a combination of bibliometric data, literature survey and conceptual analysis, the purpose being to determine the extent which criticisms relating to domain loss and inequity can be sustained. The paper argues that the risk of domain loss is very real, but that recent language planning interventions may help avert the danger. As regards inequality, we argue that while language is still a barrier for some scholars, it seems to be diminishing in importance, with non-language factors surpassing them as sources of disadvantage. At the end of the paper some tentative suggestions are made for the amelioration of language-based disadvantage in academic publication.

  11. Random-Access Technique for Self-Organization of 5G Millimeter-Wave Cellular Communications

    Directory of Open Access Journals (Sweden)

    Jasper Meynard Arana

    2016-01-01

    Full Text Available The random-access (RA technique is a key procedure in cellular networks and self-organizing networks (SONs, but the overall processing time of this technique in millimeter-wave (mm-wave cellular systems with directional beams is very long because RA preambles (RAPs should be transmitted in all directions of Tx and Rx beams. In this paper, two different types of preambles (RAP-1 and RAP-2 are proposed to reduce the processing time in the RA stage. After analyzing the correlation property, false-alarm probability, and detection probability of the proposed RAPs, we perform simulations to show that the RAP-2 is suitable for RA in mm-wave cellular systems with directional beams because of the smaller processing time and high detection probability in multiuser environments.

  12. Secure Access Control and Authority Delegation Based on Capability and Context Awareness for Federated IoT

    DEFF Research Database (Denmark)

    Anggorojati, Bayu; Mahalle, Parikshit N.; Prasad, Neeli R.

    2013-01-01

    Access control is a critical functionality in Internet of Things (IoT), and it is particularly promising to make access control secure, efficient and generic in a distributed environment. Another an important property of access control system in the IoT is flexibility which can be achieved...

  13. A Security Architecture for Data Aggregation and Access Control in Smart Grids

    CERN Document Server

    Ruj, Sushmita; Stojmenovic, Ivan

    2011-01-01

    We propose an integrated architecture for smart grids, that supports data aggregation and access control. Data can be aggregated by home area network, building area network and neighboring area network in such a way that the privacy of customers is protected. We use homomorphic encryption technique to achieve this. The consumer data that is collected is sent to the substations where it is monitored by remote terminal units (RTU). The proposed access control mechanism gives selective access to consumer data stored in data repositories and used by different smart grid users. Users can be maintenance units, utility centers, pricing estimator units or analyzing and prediction groups. We solve this problem of access control using cryptographic technique of attribute-based encryption. RTUs and users have attributes and cryptographic keys distributed by several key distribution centers (KDC). RTUs send data encrypted under a set of attributes. Users can decrypt information provided they have valid attributes. The ac...

  14. DESIGN AND IMPLEMENTATION OF ROLE BASE ACCESS CONTROL SYSTEM FOR NETWORK RESOURCES

    Directory of Open Access Journals (Sweden)

    S.R. Kodituwakku

    2010-11-01

    Full Text Available Role Based Access Control is very useful for providing a high level description of access control for organizational applications. This paper proposes a role based framework that deals with security problems in an intranet environment. The proposed framework protects intranet resources from unauthorized users. The salient feature of the framework is that it allows intranet users to access only authorized resources. It consists of two kinds of role hierarchies: global role hierarchy and local role hierarchy, and two levels of permissions: server permission and object permission. They simplify the way of structuring authority and responsibility in the whole intranet and the allocation of privileges for different objects within a particular server. The proposed framework is implemented over Windows platform and tested for the validity. The test results indicated that it can successfully be used to control accessing network objects.

  15. Improving the Effectiveness of Communication Headsets with Active Noise Reduction: Influence of Control Structure

    Science.gov (United States)

    2005-04-01

    for two circumaural communication headsets with similar passive, and active, noise reductions, one with an analog feedback control system and the...the feedback control system to maintain stability of the feedback loop, as well as the presence of communication sounds sensed by the control

  16. Multimedia Network Communication Access Technology Research%多媒体网络通信接入技术研究

    Institute of Scientific and Technical Information of China (English)

    黄跃东; 张佳乐

    2011-01-01

    The development of science and technology,the lives of people has brought great changes,many of the human dream has become reality,multimedia technology is a major achievement of modern science and technology one.As the network technology and computer technology,cheaper and convenient network technology and tools constantly available,creating a network of multi-media era.Article briefly describes the multimedia network communication technology,which focused on the multimedia network communication access technology.%科学技术的发展给人们的生活带来了巨大的改变,人类的很多梦想已经变成了现实,多媒体技术正是现代科学技术的重要成就之一。随着网络技术和计算机技术的发展,更为廉价而方便的网络技术和工具不断面世,开创了网络多媒体时代。文章简单介绍了多媒体网络通信技术,主要探讨了多媒体网络通信接入技术。

  17. Online Verification of Control Parameter Calculations in Communication Based Train Control System

    CERN Document Server

    Bu, Lei; Wang, Linzhang; Li, Xuandong

    2011-01-01

    Communication Based Train Control (CBTC) system is the state-of-the-art train control system. In a CBTC system, to guarantee the safety of train operation, trains communicate with each other intensively and adjust their control modes autonomously by computing critical control parameters, e.g. velocity range, according to the information they get. As the correctness of the control parameters generated are critical to the safety of the system, a method to verify these parameters is a strong desire in the area of train control system. In this paper, we present our ideas of how to model and verify the control parameter calculations in a CBTC system efficiently. - As the behavior of the system is highly nondeterministic, it is difficult to build and verify the complete behavior space model of the system online in advance. Thus, we propose to model the system according to the ongoing behavior model induced by the control parameters. - As the parameters are generated online and updated very quickly, the verification...

  18. Chronic non-communicable disease and healthcare access in middle-aged and older women living in Soweto, South Africa.

    Directory of Open Access Journals (Sweden)

    Daniel Lopes Ibanez-Gonzalez

    Full Text Available The aim of the current study was to describe the healthcare access, beliefs, and practices of middle-aged and older women residing in Soweto. This is a cross-sectional study of the primary (female caregivers of the Birth to Twenty Cohort, based in Soweto, South Africa. The study instrument was administered to 1 102 caregivers as part of routine annual data collection. Over half the respondents (50.7% reported having at least one chronic non-communicable disease (CND, only a small portion (33.3% of whom reported accessing a healthcare service in the last 6 months. Reported availability of private medical practice and government clinics was high (75.1% and 61.5% respectively. The low utilisation of healthcare services by women with CND is a concern in terms of healthcare management. There is a need to further investigate how healthcare beliefs are formed, as well as the feasibility of programmes to support the ongoing management of CND in Soweto.

  19. A novel and efficient user access control scheme for wireless body area sensor networks

    Directory of Open Access Journals (Sweden)

    Santanu Chatterjee

    2014-07-01

    Full Text Available Wireless body area networks (WBANs can be applied to provide healthcare and patient monitoring. However, patient privacy can be vulnerable in a WBAN unless security is considered. Access to authorized users for the correct information and resources for different services can be provided with the help of efficient user access control mechanisms. This paper proposes a new user access control scheme for a WBAN. The proposed scheme makes use of a group-based user access ID, an access privilege mask, and a password. An elliptic curve cryptography-based public key cryptosystem is used to ensure that a particular legitimate user can only access the information for which he/she is authorized. We show that our scheme performs better than previously existing user access control schemes. Through a security analysis, we show that our scheme is secure against possible known attacks. Furthermore, through a formal security verification using the AVISPA (Automated Validation of Internet Security Protocols and Applications tool, we show that our scheme is also secure against passive and active attacks.

  20. Disparities in Health Information Access: Results of a County-Wide Survey and Implications for Health Communication.

    Science.gov (United States)

    Kelley, Megan S; Su, Dejun; Britigan, Denise H

    2016-01-01

    Health knowledge and behavior can be shaped by the extent to which individuals have access to reliable and understandable health information. Based on data from a population-based telephone survey of 1,503 respondents of ages 18 years and older living in Douglas County, Nebraska, in 2013, this study assesses disparities in health information access and their related covariates. The two most frequently reported sources of health information are the Internet and health professionals, followed by print media, peers, and broadcast media. Relative to non-Hispanic Whites, Blacks are more likely to report health professionals as their primary source of health information (odds ratio [OR] = 2.61, p < .001) and less likely to report peers (OR = 0.39, p < .05). A comparison between Whites and Hispanics suggests that Hispanics are less likely to get their health information through the Internet (OR = 0.51, p < .05) and more likely to get it from broadcast media (OR = 4.27, p < .01). Relative to their counterparts, participants with no health insurance had significantly higher odds of reporting no source of health information (OR = 3.46, p < .05). Having no source of health information was also associated with an annual income below $25,000 (OR = 2.78, p < .05 compared to middle income range) and being born outside of the United States (OR = 5.00, p < .05). Access to health information is lowest among society's most vulnerable population groups. Knowledge of the specific outlets through which people are likely to obtain health information can help health program planners utilize the communication channels that are most relevant to the people they intend to reach.